Changes

Every wireless communication system involves a transmitter that transmits some sort of signal (voice, video, data, etc[[Image:Splash-prop.)jpg|right|720px]]<strong><font color="#4e1985" size="4">True 3D, a receiver that receives and detects the transmitted signalCoherent, and a channel in which the signal is transmitted into the air and travels from the location of the transmitter to the location of the receiverPolarimetric Ray Tracer That Simulates Very Large Urban Scenes In Just Few Minutes!</font></strong><table><tr><td>[[image:Cube-icon. The channel is the physical medium in which the electromagnetic waves propagatepng | link=Getting_Started_with_EM.The successful design of a communication system depends on an accurate Cube]] [[image:cad-ico.png | link budget analysis that determines whether the receiver receives adequate signal power to detect it against the background noise=Building_Geometrical_Constructions_in_CubeCAD]] [[image:fdtd-ico. The simplest channel is the free spacepng | link=EM. Real communication channels, however, are more complicated and involve a large number of wave scatterersTempo]] [[image:static-ico. For example, in an urban environment, the obstructing buildings, vehicles and vegetation reflect, diffract or attenuate the propagating radio wavespng | link=EM. As a result, the receiver receives a distorted signal that contains several components with different power levels and different time delays arriving from different anglesFerma]] [[image:planar-ico.png | link=EM.Picasso]] [[image:metal-ico.png | link=EM.Libera]] [[image:po-ico.png | link=EM.Illumina]]</td><tr></table>[[Image:Tutorial_icon.png|30px]] '''[[EM.Cube#EM.Terrano_Documentation | EM.Terrano Tutorial Gateway]]'''

The different rays arriving at a receiver location create constructive and destructive interference patterns[[Image:Back_icon. This is known as the multipath effectpng|30px]] '''[[EM. This together with the shadowing effects caused by building obstructions lead Cube | Back to channel fading. In many wireless applications, the total received power by the receiver is all that matters. In some others, the angle of arrival of the rays as well as their polarization are of immense interest. A fully polarimetric, coherent ray tracer like EM.CubeMain Page]]'s Shooting-and-Bouncing-Rays (SBR) solver lets you compute and resolve all the rays received by a receiver including their power levels, time delays and angles of arrival.''==Product Overview==

[[File:manuals/emagware/emcube/modules/propagation/wireless-propagation-primer/the-need-for-wireless-propagation-modeling/urban===EM.png]]Terrano in a Nutshell ===

In a free-space line-of-sight (LOS) communication system, the signal propagates directly from the transmitter to the receiver without encountering any obstacles (scatterers)[[Image:Info_icon. Electromagnetic waves propagate in the form of spherical waves with a functional dependence of e^j(ω^t-k₀R)/R, where R is the distance between the transmitter and receiver, ω = 2πf, f is the signal frequency, k₀ = ω/c = 2π/λ₀, c is the speed of light, and λ₀ is the free-space wavelength at the operational frequency. By the time the signal arrives at the location of the receiver, it undergoes two changes. It is attenuated and its power drops by a factor of 1/R², and additionally, it experiences a phase shift of 2πR/λ₀, which is equivalent to a time delay of R/c. The signal attenuation from the transmitter png|30px]] Click here to learn more about the receiver is usually quantified by '''Path Loss[[Basic Principles of SBR Ray Tracing | Basic SBR Theory]]''' defined as the ratio of the received signal power (P_R) to the transmitted signal power (P_T). Assuming isotropic transmitting and receiving radiators (i.e. radiating uniformly in all directions), the Path Loss in a free-space line-of-sight communication system is given by Friis’ formula:

<table><tr><td> [[FileImage:manuals/emagware/emcube/modules/Manhattan1.png|thumb|left|420px|A large urban propagationscene featuring lower Manhattan.]]</wireless-propagation-primertd></free-space-propagation-channeltr></friis1.png]]table>

The above formula assumes that the receiving antenna is polarization-matched=== EM. Normally, there is a polarization mismatch between Terrano as the transmitting and receiving antennasPropagation Module of EM. In the case of directional transmitting and receiving antennas, Friis’ formula takes the following form:Cube ===

EM.Terrano is the ray tracing '''Propagation Module''' of '''[[File:manuals/emagware/emcube/modules/propagation/wireless-propagation-primer/free-space-propagation-channel/friis2EM.pngCube]]''', a comprehensive, integrated, modular electromagnetic modeling environment. EM.Terrano shares the visual interface, 3D parametric CAD modeler, data visualization tools, and many more utilities and features collectively known as [[Building_Geometrical_Constructions_in_CubeCAD | CubeCAD]] with all of [[EM.Cube]]'s other computational modules.

where '''u_T''With the seamless integration of EM.Terrano with [[EM.Cube]]' s other modules, you can now model complex antenna systems in [[EM.Tempo]], [[EM.Libera]], [[EM.Picasso]] or [[EM.Illumina]], and '''u_R''' are generate antenna radiation patterns that can be used to model directional transmitters and receivers at the unit polarization vectors two ends of your propagation channel. Conversely, you can analyze a propagation scene in EM.Terrano, collect all the transmitting rays received at a certain receiver location and receiving antennasimport them as coherent plane wave sources to [[EM.Tempo]], and G_T and G_R are their gains[[EM.Libera]], respectively[[EM.Picasso]] or [[EM.Illumina]].

[[FileImage:manuals/emagware/emcube/modules/propagation/wireless-propagation-primer/free-space-propagation-channel/losInfo_icon.png|30px]]<br /> Figure 1: A Line-of-Sight (LOS) Propagation ScenarioClick here to learn more about '''[[Getting_Started_with_EM.Cube | EM.Cube Modeling Environment]]'''.

== Multipath Propagation Channel = Advantages & Limitations of EM.Terrano's SBR Solver ===

FreeEM.Terrano's SBR simulation engine utilizes an intelligent ray tracing algorithm that is based on the concept of k-dimensional trees. A k-d tree is a space line-ofpartitioning data structure for organizing points in a k-sight communications is an ideal scenario dimensional space. k-d trees are particularly useful for searches that is typically used to model aerial or space applicationsinvolve multidimensional search keys such as range searches and nearest neighbor searches. In ground-based systems, the presence of the ground as a very typical large reflecting surface affects the signal radio propagation to scene, there might be a large extent. Along the path number of rays emanating from a the transmitter to a receiver, the signal that may also encounter many never hit any obstacles and scatterers such as buildings. For example, vegetation, etc. In upward-looking rays in an urban canyon environment with many buildings of different heights and other scatterers, a line of sight between propagation scene quickly exit the transmitter and receiver can hardly be establishedcomputational domain. In such casesRays that hit obstacles on their path, on the propagating signals bounce back and forth among the building surfaces. It is these other hand, generate new reflected or diffracted signals that are often received and detected by the receiver. Such environments are referred to as “multipath”transmitted rays. The group of k-d tree algorithm traces all these rays arriving at systematically in a specific receiver location experience different attenuations very fast and different time delaysefficient manner. This gives rise to constructive and destructive interference patterns that cause Another major advantage of k-d trees is the fast fading. As a receiver moves locally, the receiver power level fluctuates sizably due to these fading effectsprocessing of multi-transmitters scenes.

The use of statistical models for prediction of fading effects EM.Terrano performs fully polarimetric and coherent SBR simulations with arbitrary transmitter antenna patterns. Its SBR simulation engine is widely popular among communication system designersa true asymptotic &quot;field&quot; solver. These models The amplitudes and phases of all the three vectorial field components are either based on measurement data or derived computed, analyzed and preserved throughout the entire ray tracing process from simplistic analytical frameworksthe source location to the field observation points. The statistical models often exhibit considerable errors especially You can visualize the magnitude and phase of all six electric and magnetic field components at any point in areas having mixed the computational domain. In most scenes, the buildings and the ground or terrain can be assumed to be made of homogeneous materials. These are represented by their electrical properties such as permittivity &epsilon;_r and electric conductivity &sigma;. More complex scenes may involve a multilayer ground or multilayer building sizeswalls. In such cases, one needs to perform a physics-based, site-specific analysis of can no longer use the propagation environment to accurately identify and establish all the possible signal paths from the transmitter to the receiversimple reflection or transmission coefficient formulas for homogeneous medium interfaces. This involves an electromagnetic analysis of EM.Terrano calculates the scene with all reflection and transmission coefficients of its geometrical multilayer structures as functions of incident angle, frequency and physical detailspolarization and uses them at the respective specular points.  

Link budget analysis for a multipath channel It is a challenging task due very important to the large size of the computational domains involved. Typical propagation scenes usually involve length scales keep in mind that SBR is an asymptotic electromagnetic analysis technique that is based on Geometrical Optics (GO) and the order Uniform Theory of thousands of wavelengthsDiffraction (UTD). To calculate the path loss between the transmitter and receiverIt is not a &quot;full-wave&quot; technique, one must solve and it does not provide a direct numerical solution of Maxwell's equations in an extremely large space. Full-wave numerical techniques like the Finite Difference Time Domain (FDTD) method, which require SBR makes a fine discretization number of assumptions, chief among them, a very high operational frequency such that the computational domainlength scales involved are much larger than the operating wavelength. Under this assumed regime, electromagnetic waves start to behave like optical rays. Virtually all the calculations in SBR are therefore impractical based on far field approximations. In order to maintain a high computational speed for solving large-scale urban propagation problems, EM. The prcatical solution is Terrano ignores double diffractions. Diffractions from edges give rise to use asymptotic techniques such as SBR, which utilize analytical techniques over a large distances rather than a brute force discretization number of the entire computational domainnew secondary rays. Such asymptotic techniques, The power of coursediffracted rays drops much faster than reflected rays. In other words, have to compromise modeling accuracy for practical computation feasibilityan edge-diffracted ray does not diffract again from another edge in EM.Terrano. However, reflected and penetrated rays do get diffracted from edges just as rays emanated directly from the sources do.

<table><tr><td> [[FileImage:manuals/emagware/emcube/modules/propagation/wireless-propagation-primer/Multipath_Rays.png|thumb|left|500px|A multipath-urban propagation-channel/multi1_tnscene showing all the rays collected by a receiver.png]]</td></tr></table>

Figure 1: A multipath propagation scene showing all the rays arriving == EM.Terrano Features at a particular receiver.Glance ==

== The SBR Method = Scene Definition / Construction ===

EM.Cube's Propagation Module provides an asymptotic ray tracing simulation engine that is based on a technique known as Shooting-<ul> <li> Buildings/blocks with arbitrary geometries and-Bouncing-Rays (SBR). In this technique, propagating spherical waves are modeled as ray tubes material properties</li> <li> Buildings/blocks with impenetrable surfaces or beams that emanate from a sourcepenetrable surfaces using thin wall approximation</li> <li> Multilayer walls for indoor propagation scenes</li> <li> Penetrable volume blocks with arbitrary geometries and material properties</li> <li> Import of shapefiles and STEP, travel in space, bounce from obstacles IGES and are collected by the receiver. As rays propagate away from their source STL CAD model files for scene construction</li> <li> Terrain surfaces with arbitrary geometries and material properties and random rough surface profiles</li> <li> Import of digital elevation map (transmitterDEM)terrain models</li> <li> Python-based random city wizard with randomized building locations, they begin to spread (extents and orientations</li> <li> Python-based wizards for generation of parameterized multi-story office buildings and several terrain scene types</li> <li> Standard half-wave dipole transmitters and receivers oriented along the principal axes</li> <li> Short Hertzian dipole sources with arbitrary orientation</li> <li> Isotropic receivers or diverge) over distance. In receiver grids for wireless coverage modeling</li> <li> Radiator sets with 3D directional antenna patterns (imported from other words, the cross section modules or footprint external files)</li> <li> Full three-axis rotation of a ray tube expands as a function of the distance from the source. EM.Cube uses an accurate equiimported antenna patterns</li> <li> Interchangeable radiator-angular ray generation scheme to that produces almost identical ray tubes in all directions to satisfy energy based definition of transmitters and power conservation requirements.receivers (networks of transceivers)</li></ul>

# Reflection <ul> <li> Fully 3D polarimetric and coherent Shoot-and-Bounce-Rays (SBR) simulation engine</li> <li> GTD/UTD diffraction models for diffraction from the locally flat building edges and terrain</li> <li> Triangular surfacemesh generator for discretization of arbitrary block geometries</li># Transmission <li> Super-fast geometrical/optical ray tracing using advanced k-d tree algorithms</li> <li> Intelligent ray tracing with user defined angular extents and resolution</li> <li> Ray reflection, edge diffraction and ray transmission through multilayer walls and material volumes</li> <li> Communication link analysis for superheterodyne transmitters and receivers</li> <li> 17 digital modulation waveforms for the locally flat surfacecalculation of E_b/N₀ and Bit error rate (BER)</li># Diffraction from <li> Incredibly fast frequency sweeps of the entire propagation scene in a single SBR simulation run</li> <li> Parametric sweeps of scene elements like building properties, or radiator heights and rotation angles</li> <li> Statistical analysis of the propagation scene</li> <li> Polarimetric channel characterization for MIMO analysis</li> <li> "Almost real-time" Polarimatrix solver using an edge existing ray database</li> <li> "Almost real-time" transmitter sweep using the Polarimatrix solver</li> <li> "Almost real-time" rotational sweep for modeling beam steering using the Polarimatrix solver</li> <li> "Almost real-time" mobile sweep for modeling mobile communications between two conjoined locally flat surfacesTx-Rx pairs along a mobile path using the Polarimatrix solver</li></ul>

EM.Cube discretizes all the objects of the scene into flat trinagular facets. Obviously, rectangular and cubic objects preserve their geometric shapes through this discretization. Objects with curved surfaces such as cylinders, cones or spheres, are approximated by === Data Generation &quotamp;polymesh&quot; representations. The geometric fidelity of the resulting mesh depends on the specified mesh edge length. When a ray hits a triangular facet, the propagating spherical wave is approximated as a plane wave at the specular point. The reflection and transmission coefficients of the surface are calculated at the operational frequency and at the particular ray incident angle. Visualization ===

A new reflected ray is generated at the specular point<ul> <li> Standard output parameters for received power, path loss, SNR, which starts traveling E_b/N₀ and bouncing around BER at each individual receiver</li> <li> Graphical visualization of propagating rays in the scene. If the obstructing surface is penetrable, a second transmitted ray is generated </li> <li> Received power coverage maps</li> <li> Link connectivity maps (based on minimum required SNR and added to the scene. If the BER)</li> <li> Color-coded intensity plots of polarimetric electric field distributions</li> <li> Incoming ray hits the edge of an obstacledata analysis at each receiver including delay, it is diffracted from that edge. This leads to the creation angles of a cone arrival and departure</li> <li> Cartesian plots of new rays, which greatly complicate the computational problem. The Uniform Theory path loss along defined paths</li> <li> Power delay profile of Diffraction (UTD) is used to calculate the wedge diffraction coefficients at the edges selected receiver</li> <li> Polar stem charts of scattering blocks. Note that reflection, transmission angles of arrival and diffraction coefficients are all dependent on the polarization departure of the incident plane wave.selected receiver</li></ul>

A receiver may receive == Building a large number of rays: direct line-of-sight rays from the transmitter, rays reflected or diffracted off the ground or terrain, rays reflected or diffracted from buildings or rays transmitted through buildings. Each received ray is characterized by its power, delay and angles of arrival, which are the spherical coordinate angles θ and φ of the incoming ray. The actual signal received and detected by the receiver is the superposition of all these rays with different power levels and different time delays. Most of the time, you will be interested Propagation Scene in the coverage map of an area, which shows how much power is received by a grid of receivers spread over the area from a given fixed transmitterEM. Terrano ==

== Ray Reflection & Transmission = The Various Elements of a Propagation Scene ===

The incidentA typical propagation scene in EM.Terrano consists of several elements. At a minimum, reflected you need a transmitter (Tx) at some location to launch rays into the scene and transmitted a receiver (Rx) at another location to receive and collect the incoming rays . A transmitter and a receiver together make the simplest propagation scene, representing a free-space line-of-sight (LOS) channel. In EM.Terrano, a transmitter represents a point source, while a receiver represents a point observable. Both a transmitter and a receiver are each characterized by associated with point objects, which are one of the many types of geometric objects you can draw in the project workspace. Your scene might involve more than one transmitter and possibly a triplet large grid of unit vectors:receivers.

* [[File:manuals/emagware/emcube/modules/A more complicated propagation/wireless-propagation-primer/ray-reflection/frml14_tn.png]] representing the incident parallel polarization vectorscene usually contains several buildings, walls, incident perpendicular polarization vector or other kinds of scatterers and incident propagation vector, respectivelywave obstructing objects.* [[File:manuals/emagware/emcube/modules/propagation/wireless-propagation-primer/ray-reflection/frml15_tnYou model all of these elements by drawing geometric objects in the project workspace or by importing external CAD models.png]] representing EM.Terrano does not organize the reflected parallel polarization vectorgeometric objects of your project workspace by their material composition. Rather, reflected perpendicular polarization vector and reflected propagation vector, respectivelyit groups the geometric objects into blocks based on a common type of interaction with incident rays.* [[File:manuals/emagware/emcube/modules/propagation/wireless-propagation-primer/ray-reflection/frml16_tnEM.png]] representing Terrano offer the transmitted parallel polarization vector, transmitted perpendicular polarization vector and transmitted propagation vector, respectively.following types of object blocks:

{| class="wikitable"|-! scope="col"| Icon! scope="col"| Block/Group Type ! scope="col"| Ray Interaction Type! scope="col"| Object Types Allowed! scope="col"| Notes|-| style="width:30px;" | [[File:manuals/emagware/emcube/modules/propagation/wirelessimpenet_group_icon.png]]| style="width:150px;" | [[Glossary of EM.Cube's Materials, Sources, Devices & Other Physical Object Types#Impenetrable Surface | Impenetrable Surface]]| style="width:200px;" | Ray reflection, ray diffraction| style="width:250px;" | All solid & surface geometric objects, no curve objects| style="width:300px;" | Basic building group for outdoor scenes|-propagation| style="width:30px;" | [[File:penet_surf_group_icon.png]]| style="width:150px;" | [[Glossary of EM.Cube's Materials, Sources, Devices & Other Physical Object Types#Penetrable Surface | Penetrable Surface]]| style="width:200px;" | Ray reflection, ray diffraction, ray transmission in free space| style="width:250px;" | All solid & surface geometric objects, no curve objects| style="width:300px;" | Behaves similar to impenetrable surface and uses thin wall approximation for generating transmitted rays, used to model hollow buildings with ray penetration, entry and exit |-primer/| style="width:30px;" | [[File:terrain_group_icon.png]]| style="width:150px;" | [[Glossary of EM.Cube's Materials, Sources, Devices & Other Physical Object Types#Terrain Surface | Terrain Surface]]| style="width:200px;" | Ray reflection, raydiffraction| style="width:250px;" | All surface geometric objects, no solid or curve objects | style="width:300px;" | Behaves exactly like impenetrable surface but can change the elevation of all the buildings and transmitters and receivers located above it|-| style="width:30px;" | [[File:penet_vol_group_icon.png]]| style="width:150px;" | [[Glossary of EM.Cube's Materials, Sources, Devices & Other Physical Object Types#Penetrable Volume | Penetrable Volume]]| style="width:200px;" | Ray reflection/reflect, ray diffraction, ray transmission and ray attenuation inside homogeneous material media| style="width:250px;" | All solid geometric objects, no surface or curve objects| style="width:300px;" | Used to model wave propagation inside a volumetric material block, also used for creating individual solid walls and interior building partitions and panels in indoor scenes|-| style="width:30px;" | [[File:base_group_icon.png]]| style="width:150px;" | [[Glossary of EM.Cube's Materials, Sources, Devices & Other Physical Object Types#Base Location Set | Base Location Set]]| style="width:200px;" | Either ray generation or ray reception| style="width:250px;" | Only point objects| style="width:300px;" | Required for the definition of transmitters and receivers|-| style="width:30px;" | [[File:scatterer_group_icon.png]]| style="width:150px;" | [[Glossary of EM.Cube's Materials, Sources, Devices & Other Physical Object Types#Point Scatterer Set | Point Scatterer Set]]| style="width:200px;" | Ray reception and ray scattering| style="width:250px;" | Only point, box and sphere objects| style="width:300px;" | Required for the definition of point scatterers as targets in a radar simulation |-| style="width:30px;" | [[File:Virt_group_icon.png]]| style="width:150px;" | [[Glossary of EM.Cube's Materials, Sources, Devices & Other Physical Object Types#Virtual_Object_Group | Virtual Object]]| style="width:200px;" | No ray interaction| style="width:250px;" | All types of objects| style="width:300px;" | Used for representing non-physical items |}

The Incident, Reflected and Transmitted Rays at Click on each type to learn more about it in the Interface Between Two Dielectric Media[[Glossary of EM.Cube's Materials, Sources, Devices & Other Physical Object Types]].

The reflected ray Impenetrable surfaces, penetrable surfaces, terrain surfaces and penetrable volumes represent all the objects that obstruct the propagation of electromagnetic waves (rays) in the free space. What differentiates them is assumed the types of physical phenomena that are used to originate from model their interaction with the impinging rays. EM.Terrano discretizes geometric objects into a virtual image source pointnumber of flat facets. The three triplets constitute three orthonormal basis systems. Belowfield intensity, it is assumed that phase and power of the two dielectric media have permittivities &epsilon;₁ reflected and &epsilon;₂, and permeabilities &mu;₁ and &mu;₂, respectivelytransmitted rays depend on the material properties of the obstructing facet. A lossy medium with The specular surface of a conductivity &sigma; facet can be modeled by locally as a complex permittivity &epsilon;_r = &epsilon;'_r –j&sigma;/&epsilon;₀simple homogeneous dielectric half-space or as a multilayer medium. Assuming '''n''' to be the unit normal to the interface plane between the two mediaIn that respect, and Z₀ = 120&Omega; , the incident polarization vectors as well as all the reflected and transmitted vectors are found obstructing objects such asbuildings, walls, terrain, etc. behave in a similar way:

[[File:manuals/emagware/emcube/modules/propagation/wireless-propagation-primer/* They terminate an impinging ray-and replace it with one or more new rays.* They represent a specular interface between two media of different material compositions for calculating the reflection/frml1, transmission or diffraction coefficients.png]]

The reflected unit vectors An outdoor propagation scene typically involves several buildings modeled by impenetrable surfaces. Rays hit the facets of impenetrable buildings and bounce back, but they do not penetrate the object. It is assumed that the interior of such buildings are found highly dissipative due to wave absorption or diffusion. An indoor propagation scene typically involves several walls, a ceiling and a floor arranged according to a certain building layout. Penetrable surfaces are used to model the exterior and interior walls of buildings. Rays reflect off these surfaces and diffract off their edges. They also penetrate the thin surface and continue their path in the free space on the other side of the wall. Terrain surfaces with irregular shapes or possibly random rough surfaces are used as:an alternative to the flat global ground. You can also build mixed scenes involving both impenetrable and penetrable blocks or irregular terrain. In the context of a propagation scene, penetrable volumes are often used to model block of rain, fog or vegetation. Base location sets are used to geometrically represent point transmitters and point receivers in the project workspace.

[[File:manuals/emagware/emcube/modules/propagation/wirelessSometimes it is helpful to draw graphical objects as visual clues in the project workspace. These non-propagation-primer/ray-reflection/frml2physical objects must belong to a virtual object group. Virtual objects are not discretized by EM.Terrano's mesh generator, and they are not passed onto the input data files of the SBR simulation engine.png]]

The transmitted unit vectors are found as<table><tr><td> [[Image:PROP MAN2.png|thumb|left|720px|An urban propagation scene generated by EM.Terrano's "Random City" and "Basic Link" wizards. It consists of 25 cubic brick buildings, one transmitter and a large two-dimensional array of receivers. ]]</td></tr></table>

<table><tr><td> [[FileImage:manuals/emagware/emcube/modules/propagation/wireless-propagation-primer/ray-reflection/frml4PROP MAN1.png|thumb|left|480px|EM.Terrano's navigation tree.]]</td></tr></table>

[[File:manuals/emagware/emcube/modules/propagation/wireless-propagation-primer/ray-reflection/frml5It is recommended that you first create block groups, and then draw new objects under the active block group. However, if you start a new EM.Terrano project from scratch, and start drawing a new object without having previously defined any block groups, a new default impenetrable surface group is created and added to the navigation tree to hold your new CAD object. You can always change the properties of a block group later by accessing its property dialog from the contextual menu. You can also delete a block group with all of its objects at any time.png]]

The reflection coefficients at {{Note|You can only import external CAD models (STEP, IGES, STL, DEM, etc.) only to the interface are calculated for CubeCAD module. You can then transfer the two parallel and perpendicular polarizations as:imported objects from CubeCAD to EM.Terrano.}}

In &quot;Thin Wall Approximation&quot;, we assume that <table><tr><td> [[Image:PROP MAN3.png|thumb|left|720px|Moving the terrain model of Mount Whitney originally imported from an incident ray gives rise external digital elevation map (DEM) file to two rays, one is reflected at the specular point, and the other is transmitted almost EM.Terrano.]]</td></tr><tr><td>[[Image:PROP MAN4.png|thumb|left|720px|The imported terrain model of Mount Whitney shown in the same direction as the incident rayEM. The reflected ray is assumed to originate from Terrano's project workspace under a virtual image source point. Similar to the case of reflection and transmission at the interface between two dielectric media, here too we have three triplets of unit vectors, which all form orthonormal basis systemsterrain group called "Terrain_1".]]</td></tr></table>

The Incident In EM.Terrano, buildings and Transmitted Rays through all other geometric objects are initially drawn on the XY plane. In other words, the Z-coordinates of the local coordinate system (LCS) of all blocks are set to zero until you change them. Since the global ground is located a Thin Wallz = 0, your buildings are seated on the ground. When your propagation scene has an irregular terrain, you would want to place your buildings on the surface of the terrain and not buried under it. This can be done automatically as part of the definition of the block group. Open the property dialog of a block group and check the box labeled '''Adjust Block to Terrain Elevation'''. All the objects belonging to that block are automatically elevated in the Z direction such that their bases sit on the surface of their underlying terrain. In effect, the LCS of each of these individual objects is translated along the global Z-axis by the amount of the Z-elevation of the terrain object at the location of the LCS.

The transmission coefficients {{Note| You have to make sure that the resolution of your terrain, its variation scale and building dimensions are calculated for all comparable. Otherwise, on a rapidly varying high-resolution terrain, you will have buildings whose bottoms touch the two parallel terrain only at a few points and perpendicular polarizations as:parts of them hang in the air.}}

<table><tr><td> [[FileImage:manuals/emagware/emcube/modules/propagation/wireless-propagation-primer/transmission-through-thin-walls/frml20PROP MAN5.png|thumb|left|480px|The property dialog of impenetrable surface showing the terrain elevation adjustment box checked.]]</td></tr></table>

[[File:manuals/emagware/emcube/modules/propagation/wireless-propagation-primer/transmission-through-thin-walls/frml21== EM.png]]Terrano's Ray Domain & Global Environment ==

== Wedge Diffraction From Edges = Why Do You Need a Finite Computational Domain? ===

For the purpose of calculation of diffraction from building edges, we define a &quot;Wedge&quot; as having two faces, the 0-face and the ''n''-face. The wedge angle is α = (2-''n'')π, where the parameter ''n'' is required SBR simulation engine requires a finite computational domain for the calculation of diffraction coefficientsray termination. All the diffracted stray rays lie on that emanate from a cone with source inside this finite domain and hit its vertex at boundaries are terminated during the simulation process. Such rays exit the diffraction point computational domain and a wedge angle equal travel to the angle infinity, with no chance of incidence ever reaching any receiver in the opposite directionscene. A diffracted ray is assumed to originate from When you define a virtual image source pointpropagation scene with various elements like buildings, walls, terrain, etc. Three triplets of unit vectors are defined , a dynamic domain is automatically established and displayed as follows:a green wireframe box that surrounds the entire scene. Every time you create a new object, the domain box is automatically adjusted and extended to enclose all the objects in the scene.

* [[File:manuals/emagware/emcube/modules/propagation/wireless-propagation-primer/wedge-diffraction/frml19_tn.png]] representing To change the unit vector normal to the edge and lying in the plane of the 0-faceray domain settings, follow the unit vector normal to the 0-face, and the unit vector along the edge, respectively.* [[Fileprocedure below:manuals/emagware/emcube/modules/propagation/wireless-propagation-primer/wedge-diffraction/frml17_tn.png]] representing the incident forward polarization vector, incident backward polarization vector and incident propagation vector, respectively.* [[File:manuals/emagware/emcube/modules/propagation/wireless-propagation-primer/wedge-diffraction/frml18_tn.png]] representing the diffracted forward polarization vector, diffracted backward polarization vector and diffracted propagation vector, respectively.

The three triplets constitute three orthonormal basis systems* Open the Ray Domain Settings Dialog by clicking the '''Domain''' [[File:image025. The propagation vector jpg]] button of the '''kSimulate Toolbar''', or by selecting ' ''Menu > Simulate > Computational Domain > Settings...''', or by right-clicking on the '''Ray Domain''' item of the diffracted ray has to be constructed based on navigation tree and selecting '''Domain Settings...''' from the diffraction cone contextual menu, or simply using the keyboard shortcut {{key|Ctrl+A}}.* The size of the Ray domain is specified in terms of six '''Offset''' parameters along the ±X, ±Y and ±Z directions. The default value of all these six offset parameters is 10 project units. Change these values as follows:you like.* You can also change the color of the domain box using the {{key|Color}} button.* After changing the settings, use the {{key|Apply}} button to make the changes effective while the dialog is still open.

<table><tr><td> [[FileImage:manuals/emagware/emcube/modules/propagation/wireless-propagation-primer/wedge-diffraction/frml8PROP15.png|thumb|left|480px|EM.Terrano's domain settings dialog.]]</td></tr></table>

where === Understanding the resolution of the angle &theta;_w is chosen to be the same as the resolution of the incident ray.Global Ground ===

[[File:manualsMost outdoor and indoor propagation scenes include a flat ground at their bottom, which bounces incident rays back into the scene. EM.Terrano provides a global flat ground at z = 0. The global ground indeed acts as an impenetrable surface that blocks the entire computational domain from the z = 0 plane downward. It is displayed as a translucent green plane at z = 0 extending downward. The color of the ground plane is always the same as the color of the ray domain. The global ground is assumed to be made of a homogeneous dielectric material with a specified permittivity &epsilon;<sub>r</emagwaresub> and electric conductivity &sigma;. By default, a rocky ground is assumed with &epsilon;<sub>r</emcubesub> = 5 and &sigma; = 0.005 S/modules/propagation/wirelessm. You can remove the global ground, in which case, you will have a free space scene. To disable the global ground, open up the "Global Ground Settings" dialog, which can be accessed by right clicking on the '''Global Ground''' item in the Navigation Tree and selecting '''Global Ground Settings... '''Remove the check mark from the box labeled '''&quot;Include Half-propagationSpace Ground (z&lt;0)&quot;''' to disable the global ground. This will also remove the green translucent plane from the bottom of your scene. You can also change the material properties of the global ground and set new values for the permittivity and electric conductivity of the impenetrable, half-primer/wedge-diffraction/diffractspace, dielectric medium.png]]

The Incident Ray and Diffract Ray Cone at Alternatively, you can use EM.Terrano's '''Empirical Soil Model''' to define the Edge material properties of the global ground. This model requires a Buildingnumber of parameters: Temperature in &deg;C, and Volumetric Water Content, Sand Content and Clay Content all as percentage.

<table><tr><td> [[FileImage:manuals/emagware/emcube/modules/propagation/wireless-propagation-primer/wedge-diffraction/frml9Global environ.png|thumb|left|720px|EM.Terrano's Global Environment Settings dialog.]]</td></tr></table>

where In EM.Terrano, transmitters and receivers are indeed point radiators used for transmitting and receiving signals at different locations of the propagation scene. From a geometric point of view, both transmitters and receivers are represented by point objects or point arrays. These are grouped as base locations in the "Physical Structure" section of the navigation tree. As radiators, transmitters and receivers are defined by a radiator type with a certain far-field radiation pattern. Consistent with [[EM.Cube]]''Fs other computational modules, transmitters are categorizes as an excitation source, while receivers are categorized as a project observable. In other words, a transmitter is used to generate electromagnetic waves that propagate in the physical scene. A receiver, on the other hand, is used to compute the received fields and received signal power or signal-to-noise ratio (xSNR)'' is . For this reason, transmitters are defined and listed under the "Sources" sections of the navigation tree, while receivers are defined and listed under the Fresnel Transition function:"Observables" section.

[[File:manuals/emagware/emcube/modules/propagation/wireless-propagation-primer/wedge-diffraction/frml12EM.png]]Terrano provides three radiator types for point transmitter sets:

In #Half-wave dipole oriented along one of the above equationsthree principal axes#Two collocated, we haveorthogonally polarized, isotropic radiators #User defined (arbitrary) antenna with imported far-field radiation pattern

[[File:manuals/emagware/emcube/modules/propagation/wireless-propagation-primer/wedge-diffraction/frml10EM.png]]Terrano also provides three radiator types for point receiver sets:

[[File:manuals/emagware/emcube/modules/propagation/wireless#Half-propagationwave dipole oriented along one of the three principal axes#Polarization-primer/wedgematched isotropic radiator#User defined (arbitrary) antenna with imported far-diffraction/frml13.png]]field radiation pattern

where ''N^±'' The default transmitter and receiver radiator types are the integers which most closely satisfy the equations 2''n''&pi;''N^±'' both vertical (Z- &nu; = ±&pi;directed) half-wave dipoles.

EM.Cube's SBR simulation engine can be used as a versatile *By defining point objects or point arrays under physical base location sets in the navigation tree and powerful asymptotic electromagnetic (EM) solver. If you compare EM.Cube's Propagation Module then associating them with its other computational modules, you will notice a lot of similarities. While other modules group objects primarily by their material propertiestransmitter or receiver set*Using Python commands emag_tx, Propagation Module categorizes the types of obstructing surfaces. Besides sharing the same ray-surface interaction mechansimsemag_rx, all the objects belonging to a surface group also share the same material properties. Propagation Module offers similar source types and similar observable types as the other computational modules. For instanceemag_tx_array, the Hertzian dipole sources used in a SBR simulation are identical to those offered in POemag_rx_array, MoM3D emag_tx_line and Planar modules. The plane wave sources are identical across all computational modules. Propagation Module's sensor field planes, far field observables (either radiation patterns or RCS) and Huygens surfaces are all fully compatible with EM.Cube's other computational modules.emag_rx_line*Using the "Basic Link" wizard

As an asymptotic EM solver, the SBR engine can be used to model large-scale electromagnetic radiation and scattering problems. An example of this kind is radiation of simple or complex antennas in the presence of large scattering platforms. You have to keep === Defining a Point Transmitter Set in mind that by using an asymptotic technique in place of a full-wave method, you trade computational speed and lower memory requirements for modeling accuracy. In particular, the SBR method cannot take into account the electromagnetic coupling effects among nearby radiators or scatterers. However, when your scene spans thousands of wavelengths, an SBR simulation might often prove to be your sole practical solution.  Formal Way ===

== Novelties Of Transmitters act as sources in a propagation scene. A transmitter is a point radiator with a fully polarimetric radiation pattern defined over the entire 3D space in the standard spherical coordinate system. EM.Cube's SBR Solver ==Terrano gives you three options for the radiator associated with a point transmitter:

EM.Cube's new SBR simulation engine utilizes an intelligent ray tracing algorithm based on the concept of  k* Half-dimensional trees. A k-d tree is a space-partitioning data structure for organizing points in a k-dimensional space. k-d trees are particularly useful for searches that involve multidimensional search keys such as range searches and nearest neighbor searches. In a typical large radio propagation scene, there might be a large number of rays emanating from the transmitter that may never hit any obstacles. For example, upward-looking rays in an urban propagation scene quickly exit the computational domain. Rays that hit obstacles on their path, on the other hand, generate new reflected and transmitted rays. The k-d tree algorithm traces all these rays systematically in a very fast and efficient manner. Another major advantage of k-d trees is the fast processing of multi-transmitters scenes. Unlike the previous versions of the SBR solver which could handle one transmitter at a time and would superpose all the the resulting rays at the end of the simulation, the new SBR shoots rays from all the transmitters at the same time.   wave dipole* Orthogonally polarized isotropic radiators* User defined antenna pattern

By default, EM.Cube's new SBR simulation engine performs fully polarimetric and coherent SBR simulations with arbitrary Terrano assumes that your transmitter is a vertically polarized (Z-directed) resonant half-wave dipole antenna patterns. The new engine solves directly for the vectorial field components at the receiver locations or field observation pointsThis antenna has an almost omni-directional radiation pattern in all azimuth directions. This is far more rigorous than It also has radiation nulls along the previous versions axis of the SBR solver which primarily utilized ray power calculations based on the two vertical and horizontal polarizationsdipole. In other words, EM.Cube's new SBR engine is a truly asymptotic &quot;field&quot; solver. As a result, you You can visualize change the magntidue and phase direction of all six electric the dipole and magnetic field components at any point in orient it along the computational domainX or Y axes using the provided drop-down list. For power calculations at the receiver location, an The second choice of two orthogonally polarized isotropic, polarization-matched, receiving antenna radiators is assumedan abstract source that is used for polarimetric channel characterization as will be discussed later.       

In most scenes, You can override the buidlings default radiator option and the ground or terrain can be assumed to be made select any other kind of homogeneous materials. These are represneted by their electrical properties such as permittivity ε and electric conductivity σ. More complex scenes may involve antenna with a multilayer ground or multilayer building wallsmore complicated radiation pattern. In such casesFor this purpose, one you have to import a radiation pattern data file to EM.Terrano. You can no longer use the simple reflection model any radiating structure using [[EM.Cube]]'s other computational modules, [[EM.Tempo]], [[EM.Picasso]], [[EM.Libera]] or transmission coefficient formulas [[EM.Illumina]], and generate a 3D radiation pattern data file for homogeneous medium interfacesit. EMThe far-field radiation patter data are stored in a specially formatted file with a &quot;'''.Cube calculates RAD'''&quot; file extension. This file contains columns of spherical &phi; and &theta; angles as well as the reflection real and transmission coefficients imaginary parts of multilayer structures as functions the complex-valued far-zone electric field components '''E_&theta;''' and '''E_&phi;'''. The &theta;- and &phi;-components of incident angle, frequency and the far-zone electric field determine the polarization and uses them at of the respective specular pointstransmitting radiator.  

== Limitations of {{Note|By default, EM.Cube's SBR Solver ==Terrano assumes a vertical half-wave dipole radiator for your point transmitter set.}}

It is very important A transmitter set always needs to keep be associated with an existing base location set with one or more point objects in mind that SBR is an asymptotic electromagnetic analysis technique that is based on Geometrical Optics (GO) and the Uniform Theroy of Diffraction (UTD)project workspace. It is not a &quot;full-wave&quot; techniqueTherefore, and it does not solve Maxwell's equations directly or numerically. SBR makes you cannot define a number of assumptions, chief among them, transmitter for your scene before drawing a very high operational frequency such that the length scales involved are much larger than the operating wavelength. Under this assumed regime, electromagnetic waves start to behave like optical rays. Virtually all the calculations in SBR are based on far field approximationspoint object under a base location set. 

In order [[Image:Info_icon.png|40px]] Click here to maintain learn how to define a high computational speed for urban propagation problems, EM.Cube's SBR solver ignores double diffractions. Recall that diffractions from edges give rise to a large number of new secondary rays. The power of diffracted rays drops much faster than reflected rays. EM''[[Glossary_of_EM.Cube ignores diffracted rays that are not detected by any receiver. In other words%27s_Materials, an edge-diffracted ray does not diffract again from another edge. However_Sources, reflected and penetrated rays do get diffracted from edges just as rays emanated directly from the sources do_Devices_%26_Other_Physical_Object_Types#Point_Transmitter_Set | Point Transmitter Set]]'''.

An EM.Cube propagation scene typically consists of several elements. At a minimum, Once you need define a new transmitter (Tx) at some location to launch rays into set, its name is added in the scene '''Transmitters''' section of the navigation tree. The color of all the base points associated with the newly defined transmitter set changes, and a receiver an additional little ball with the transmitter color (Rxred by default) at another location to receive and collect appears at the incoming rayslocation of each associated base point. A You can open the property dialog of the transmitter set and modify a receiver together make the simplest propagation scene, representing a free-space line-number of-sight (LOS) channelparameters including the '''Source Power''' in Watts and the broadcast signal '''Phase''' in degrees. A The default transmitter power level is one of EM1W or 30dBm.CubeThere is also a check box labeled '''Use Custom Input Power'''s several source types, while a receiver which is one of checked by default. In that case, the power and phase boxes are enabled and you can change the default 1W power and 0&deg; phase values as you wish. [[EM.Cube]]'s several observable types". A simpler source type is a Hertzian dipoleRAD" radiation pattern files usually contain the value of &quot;Total Radiated Power&quot; in their file header. A simpler observable This quantity is a field sensor calculated based on the particular excitation mechanism that is was used to compute generate the electric and magnetic fields on a specified planepattern file in the original [[EM.Cube]] module. When the "Use Custom Input Power" check box is unchecked, EM.Terrano will use the total radiated power value of the radiation file for the SBR simulation.

An outdoor propagation scene may involve several buildings (modeled as impenetrable surfaces) and an underlying flat ground or irregular terrain surface. An indoor propagation scene may involve several walls (modeled as thin penetrable surfaces), a ceiling and a floor arranged according {{Note|In order to a certain floor plan. You can also build mixed scenes involving both impenetrable and penetrable blocks, possibly along with irregular terrain surfaces. Your sources and observables can be placed anywhere in the scene. Your transmitters and receivers can be placed outdoors or indoors. A complete list modify any of the various elements of a propagation scene is given in the '''Physical Structure''' section of Propagation Moduletransmitter set's Navigation Tree parameters, first you need to select the "User Defined Antenna" option, even if you want to keep the vertical half-wave dipole as follows:your radiator.}}

Impenetrable, penetrable and terrain surfaces all obstruct the propagation of electromagnetic waves (rays) Your transmitter in the free spaceEM. What differentiates them Teranno is the types indeed more sophisticated than a simple radiator. It consists of physical phenomena a basic "Transmitter Chain" that are contains a voltage source with a series source resistance, and connected via a segment of transmission line to a transmit antenna, which is used to model their interaction with launch the impinging raysbroadcast signal into the free space. Base points are simply used The transmitter's property dialog allows you to define the basic transmitter and receiver locations in chain. Click the scene{{key|Transmitter Chain}} button of the Transmitter Set dialog to open the transmitter chain dialog. The following sections of this manual will describe each of these elements As shown in detail. [[File:PROP14(1).png]] Figure 1: The Navigation Tree of EM.Cube's Propagation Module. == The Various Types Of Surfaces &amp; Blocks == In a SBR simulationthe figure below, you can specify the propagating rays hit characteristics of the surface of building structuresbaseband/IF amplifier, walls, terrain (or global ground) mixer and bounce back into the scene power amplifier (reflectionPA). Some rays penetrate thin walls or other penetrable surfaces including stage gains and continue their path on the other side of the surface impedance mismatch factors (transmissionIMF). The field intensity, phase and power of the reflected and transmitted rays depend on the material properties of the obstructing surface. The specular surface can be modeled as a simple homogeneous dielectric half-space or well as a multilayer structure. In that respect, the buildings, walls, terrain or even the global ground all behave in a similar way: * They terminate an impinging ray and replace it with one or more new rays.* They represent a specular interface between two media characteristics of different material compositions for calculating the reflection, transmission and possibly diffraction coefficients. EM.Cube has generalized the concept of '''Block''' as any object line segment that obstructs and affects radio wave propagation. Rays hit connects the facets of a block and bounce off PA to the surface of those facets or penetrate them and continue their propagationantenna. Rays also get diffracted off Note that the edges of these blocks. In EM.Cube's Propagation Module, blocks transmit antenna characteristics are grouped together by automatically filled using the type contents of their interaction with raysthe imported radiation pattern data file. EM.Cube currently offers three types of blocks for use in a propagation scene: # '''Impenetrable Surfaces:''' Rays hit the facets of this type of blocks The transmitter Chain dialog also calculates and bounce back, but they do not penetrate reports the object. It is assumed that the interior of such blocks or buildings are highly absorptive.# '''Penetrable Surfaces:''' These blocks represent thin surfaces that are used to model the exterior and interior walls of buildings "Total Transmitter Chain Gain" based on the &quot;Thin Wall Approximation&quot;your input. Rays reflect off the surface of penetrable surfaces When you close this dialog and diffract off their edges. They also penetrate such thin surfaces and continue their paths on return to the other side of the wall.# '''Terrain Surfaces:''' These blocks are used to provide one or more impenetrableTransmitter Set dialog, ground surfaces for you will see the propagation scene. Rays simply bounce off terrain objects. The global ground acts as a flat super-terrain that covers the bottom calculated value of the entire computational domain.  EM.Cube's Propagation Module allows you to define block groups Effective Isotropic Radiated Power (EIRP) of each of the above three typesyour transmitter in dBm. Each block group has the same color or texture and its members share the same material properties: permittivity ε_r and conductivity σ. Also, all the penetrable surfaces belonging to the same block group have the same wall thickness. You can define many different block groups with certain properties and underneath each introduce many member objects with different geometrical shapes and dimensions. The table below summarizes the characteristics of each block type:

<tbody><tr class="odd"><td align="left">'''Block Type'''</td><td align="[[File:NewTxChain.png|thumb|left">'''Physical Effects'''</td><td align="left">'''Admissible Object Types''|720px|EM.Terrano's point transmitter chain dialog.]] </td>

== Impenetrable Surfaces For Outdoor Scenes = Defining a Point Receiver Set in the Formal Way ===

In outdoor propagation scenes such Receivers act as &quot;Urban Canyons&quot;, you are primarily inetersted observables in the wireless coverage in the areas among buildingsa propagation scene. You can assume that rays bounce off the exterior walls The objective of these buildings but do not penetrate them. In other words, you ignore a SBR simulation is to calculate the transmitted rays far-zone electric fields and assume that they are either absorbed or diffused inside the buildingstotal received power at the location of a receiver. This is not an unrealistic assumption. EM.Cube offers &quot;Impenetrable Blocks&quot; You need to model buidlings define at least one receiver in outdoor propagation scenesthe scene before you can run a SBR simulation. A penetrable block has Similar to a color or texture property as well as material properties: permittivity (ε_r) and conductivity (σ). By defaulttransmitter, a brick building receiver is assumed with ε_r = 4a point radiator, too.4 and σ = 0EM.001S/m. Impinging rays are reflected from Terrano gives you three options for the facets of impenetrable buildings or diffracted from their edges.radiator associated with a point receiver set:

# Right click on either the '''Impenetrable Surfaces'''item of the Navigation Tree and select '''Insert New BlockBy default, EM...''' A dialog for setting up the block properties opens up offering Terrano assumes that your receiver is a preloaded material type vertically polarized (BrickZ-directed) with predefined color and textureresonant half-wave dipole antenna.# Specify a name for You can change the block group direction of the dipole and select a color orient it along the X or textureY axes using the provided drop-down list.# The electromagnetic model that determines rayAn isotropic radiator has a perfect omni-block interaction is selected under '''Specular Interface Type'''directional radiation pattern in all azimuth and elevation directions. Two options are available: An isotropic radiator doesn'''Standard Material''' or '''User Defined Model'''. The former is t exist physically in the default choice and requires material propertiesreal world, '''Permittivity''' (ε_r) and '''Electric Conductivity''' (σ), which are set but it can be used simply as a point in space to &quot;Brick&quot; by default. No magnetic properties are allowed for blocks.# Click compute the '''OK''' button of the dialog to accept the changes and close itelectric field.

[[File:PROP14(2)You may also define a complicated radiation pattern for your receiver set.png]]   In that case, you need to import a radiation pattern data file to EM.Terrano similar to the case of a transmitter set.

Figure 1: Propagation Module's Impenetrable Surface dialog{{Note|By default, EM.Terrano assumes a vertical half-wave dipole radiator for your point receiver set.}}

Under an impenetrable block groupSimilar to transmitter sets, you can draw any of EM.Cube's native solid define a receiver set by associating it with an existing base location set with one or surface more point objects or you can import external model files like STEP, IGES or STL. You can change in the properties of an impenetrable surfaceproject workspace. In All the property dialog of the surface group, click on the table that list the properties receivers belonging to select and highlight a row. Then, click the '''Add/Edit'''button to open up same receiver set have the &quot;Edit Layer&quot; dialogsame radiator type. In this dialog, you can change the name A typical propagation scene contains one or few transmitters but usually a large number of the material and its permittivity and electric conductivityreceivers. The box labeled &quot;Specify Loss Tangent&quot; is unchecked by default. If you check itTo generate a wireless coverage map, you can specifiy the '''Loss Tangent'''need to define an array of the material, which, in turn, updates the value of electric conductivity at the center frequency of the project. You can also use EM.Cube's Material List, which will  be explained laterpoints as your base location set.   

[[FileImage:PROP23Info_icon.png|40px]]Click here to learn how to define a '''[[Glossary_of_EM.Cube%27s_Simulation_Observables_%26_Graph_Types#Point_Receiver_Set | Point Receiver Set]]'''.

Figure 2<table><tr><td> [[Image: Propagation Module's &quot;Edit Layer&quot; Terrano L1 Fig12.png|thumb|left|480px|The point receiver set definition dialog corresponding to impenetrable surfaces.]] </td></tr></table>

A typical indoor propagation scene usually involves an arrangement of walls that represent the interior of a building<table><tr><td> [[File:NewRxProp. png|thumb|left|720px|The transmitters and receivers are then placed in the spaces among such walls. From the point property dialog of view of EM.Cube's SBR simulator, walls act like thin penetrable surfaces. EM.Cube uses the &quot;Thin Wall Approximation&quot; to model penetrable surfaces. It assumes that rays simply penetrate a wall and exit at the same specular point on the opposite side of the wall. In other words, rays are not displaced by the walls, nor do they get trapped inside the walls (no internal reflection). This is equivalent to assuming a zero thickness for penetrable surfaces for the purpose of geometrical ray tracing, while the finite thickness of the &quot;thin&quot; surface is used for electromagnetic calculation of transmission coefficient. EM.Cube offers &quot;Penetrable Surface Blocks&quot; for the construction of rooms in indoor propagation scenes as well as modeling of hollow buildings and other structures. You can define many penetrable surface groups with arbitrary thicknesses and material properties (color, texture, permittivity and electric conductivity)receiver set.]]</td></tr></table>

To define In the Receiver Set dialog, there is a new penetrable surface groupdrop-down list labeled '''Selected Element''', follow these steps:which contains a list of all the individual receivers belonging to the receiver set. At the end of an SBR simulation, the button labeled {{key|Show Ray Data}} becomes enabled. Clicking this button opens the Ray Data dialog, where you can see a list of all the received rays at the selected receiver and their computed characteristics.

# Right click on one If you choose the "user defined antenna" option for your receiver set, it indeed consists of a basic "Receiver Chain" that contains a receive antenna connected via a segment of transmission line to the '''Penetrable Surfaces'''item low-noise amplifier (LNA) that is terminated in the Navigation Tree and select '''Insert New Block..a matched load.The receiver set''' A s property dialog for setting up allows you to define the wall properties opens up offering a preloaded material type (Brick) with predefined color and texturebasic receiver chain.# Specify a name for Click the surface group and select a color or texture.# The properties {{key|Receiver Chain}} button of a penetrable surface are identical the Receiver Set dialog to those of an impenetrable surface, plus an additional thickness propertyopen the receiver chain dialog.# By defaultAs shown in the figure below, a brick wall with a thickness of 0.5 units is assumed. You you can change specify the '''Thickness''' characteristics of the penetrable surface LNA such as its gain and noise figure in dB as well as its the characteristics of the transmission line segment that connects the antenna to the LNA. Note that the receiving antenna characteristics are automatically filled from using contents of the radiation file. You have to enter values for antenna's ''Permittivity'Brightness Temperature''  ε_r and 'as well as the temperature of the transmission line and the receiver''Electric Conductivity''' σs ambient temperature.# Click the The effective '''OKReceiver Bandwidth''' button is assumed to be 100MHz, which you can change for the purpose of noise calculations. The Receive Chain dialog calculates and reports the "Noise Power" and "Total Receiver Chain Gain" based on your input. At the end of an SBR simulation, the receiver power and signal-noise ratio (SNR) of the selected receiver are calculated and they are reported in the receiver set dialog to accept in dBm and dB, respectively. You can examine the changes properties of all the individual receivers and close itall the individual rays received by each receiver in your receiver set using the "Selected Element" drop-down list.

<table><tr><td> [[File:PROP15(1)NewRxChain.png|thumb|left|720px|EM.Terrano's point receiver chain dialog.]]</td></tr></table>

Under a penetrable surface group, you can draw any of EM.Cube's native solid or surface objects or Terrano allows you can import external model files like STEP, IGES or STL. You can change the properties of a penetrable surface group including its default thickness. In the property dialog of the surface group, click on the table that list the properties to select and highlight define a rowdigital modulation scheme for your communication link. Then, click the '''Add/Edit'''button There are currently 17 waveforms to open up the &quot;Edit Layer&quot; dialog. Similar to the case of impenetrable surfaces, choose from this dialog, you can change the material properties (permittivity and electric conductivity) as well as '''Thickness''', which is expressd in the project units. You can also use EM.Cube's Material List, which will be explained later.receiver set property dialog:

[[File:PROP25*OOK*M-ary ASK*Coherent BFSK*Coherent QFSK*Coherent M-ary FSK*Non-Coherent BFSK*Non-Coherent QFSK*Non-Coherent M-ary FSK*BPSK*QPSK*Offset QPSK*M-ary PSK*DBPSK*pi/4 Gray-Coded DQPSK*M-ary QAM*MSK*GMSK (BT = 0.png]]3)

Figure 2: Propagation Module's &quot;Edit Layer&quot; dialog corresponding In the above list, you need to penetrable surfacesspecify the '''No. Levels (M)''' for the Mary modulation schemes, from which the '''No. Bits per Symbol''' is determined. You can also define a bandwidth for the signal, which has a default value of 100MHz. Once the SNR of the signal is found, given the specified modulation scheme, the E_b/N₀ parameter is determined, from which the bit error rate (BER) is calculated.

You can construct several thin walls and arrange them as rooms. A regular room can be built by placing four vertical wall objects together with an optional horizontal wall at The Shannon – Hartley Equation estimates the top for the ceiling. Alternatively, you may use EM.Cube's hollow box objects or boxes with one or two capped end(s).  '''Keep in mind that all the penetrable surfaces belonging to a group have the same wall thickness, which is initially set to 0.5 project units by default. Also, note that solid CAD objects belonging to a penetrable surface group are treated as air-filled hollow structures.''' The thickness of penetrable surfaces is implied and not visualized when displaying objects in the project workspace.channel capacity:

<math> C == Computational Domain &amp; Global Ground ==B \log_2 \left( 1 + \frac{S}{N} \right) </math>

The SBR simulation engine requires a finite computational domain. All where B in the stray rays that hit the boundaries of this finite domain are terminated during the simulation process. Such rays exit the computational domain and travel to the infinity, with no chance of ever reaching any receiver bandwidth in the scene. When you define a propagation scene with various elements like buildingsHz, walls, terrain, etc., a dynamic domain is automatically established and displayed as a wireframe box with green lines that surrounds the entire scene. Every time you create a new object, the domain C is automatically adjusted and extended to enclose all the objects channel capacity (maximum data rate) expressed in the scenebits/s. You can change the size and color of the domain box through the Ray Domain Settings Dialog, which can be accessed in one of the following three ways:

# Click the '''Domain''' [[File:manuals/emagware/emcube/modules/propagation/anatomy-The spectral efficiency of-a-propagation-scene/ray-domain/image025.jpg]] button of the Simulation Toolbar.# Select the '''Simulate''' &gt; '''Computational Domain''' &gt; '''Settings...''' item of the Simulate Menu.# Right click on the '''Ray Domain''' item of the Navigation Tree and select '''Domain Settings...'''# Use the keyboard shortcut '''Ctrl + A'''.channel is defined as

[[File:PROP15The quantity E_b/N₀ is the ratio of energy per bit to noise power spectral density.png]]It is a measure of SNR per bit and is calculated from the following equation:

Figure <math> \frac{E_b}{N_0} = \frac{ 2^\eta - 1: Propagation Module's Domain Settings dialog.}{\eta} </math>

Most outdoor and indoor propagation scenes inlcude a flat ground at their bottom, which bounces incident rays back into the scene. EM.Cube's Propagation Module provides a global flat ground at z = 0. The global ground indeed acts as an impenetrable surface that blocks the entire computational domain from the z = 0 plane downward. It is displayed as a translucent green plane at z = 0 extending downward. The color of the ground plane is always the same as the color of the ray domain. The global ground is assumed to be made of a homogeneous dielectric material with a specified permittivity ε_r and electric conductivity σ. By default, a rocky ground is assumed with ε_r = 5 and σ = 0.005 S/m. You can remove the global ground, in which case, you will have a free space scene. To disable the global ground, open up the Global Ground Settings Dialog, which can be accessed by right clicking on the '''Global Ground''' item in the Navigation Tree and selecting '''Global Ground Settings... '''Remove the check mark from the box labeled '''where &quoteta;Include Half-Space Ground (z&lt;0)&quot;''' to disable the global ground. This will also remove the green translucent plane from the bottom of your scene. You can also change the material properties of the global ground and set new values for the permittivity and electric conductivity of the impenetrable, half-space, dielectric medium. '''Do not forget to disable is the global ground if you want to model a free space propagation scenespectral efficiency.'''

[[File:PROP4The relationship between the bit error rate and E_b/N₀ depends on the modulation scheme and detection type (coherent vs.png]]non-coherent). For example, for coherent QPSK modulation, one can write:

Figure 2: Propagation Module's Global Ground Settings dialog<math> P_b = 0.5 \; \text{erfc} \left( \sqrt{ \frac{E_b}{N_0} } \right) </math> where P_b is the bit error rate and erfc(x) is the complementary error function:

<math> \text{erfc}(x) =1-\text{erf}(x) = Terrain Surfaces vs. Global Ground ==\frac{2}{\sqrt{\pi}} \int_{x}^{\infty} e^{-t^2} dt </math>

A terrain surface acts as a customThe '''Minimum Required SNR''' parameter is used to determine link connectivity between each transmitter and receiver pair. If you check the box labeled '''Generate Connectivity Map''' in the receiver set property dialog, unlevel or irregular ground for your a binary map of the propagation scene. is generated by EM.Cube's default global ground blocks the z &lt; 0 half-space everywhere Terrano, in the computational domain. You can simply trun off the global ground and create which one or more terrain objects color represents a closed link and place them arbitrarily in another represent no connection depending on the sceneselected color map type of the graph. You can also import an external terrain model or fileEM. A terrain represents an impenetrable surface with a more complex surface profile. You can have one or more terrain objects of finite extents Terrano also calculates the '''Max Permissible BER''' corresponding to the specified minimum required SNR and place them on or above displays it in the global groundreceiver set property dialog.

# While impenetrable blocks can be created using any of EM.Cube's solid When you define a new transmitter set or surface CAD object creation toolsa new receiver set, terrain objects are created either using EM.Cube's '''Terrain Generator'''or Terrano assigns a vertically polarized half-wave dipole radiator to the set by importing an external terrain filedefault. # Terrain objects belong to a special type The radiation pattern of CAD objects called &quot;Tessellated Objects&quot;this native dipole radiators is calculated using well-know expressions that are derived based on certain assumptions and approximations. For example, which differ from other regular CAD surface objects or EM.Cube's polymesh surfaces.# Terrain surfaces do not diffract impinging rays at their many small edges.# Terrain objects affect the elevation far-zone electric field of other objects or transmitters or receivers that are located above them.a vertically-polarized dipole antenna can be expressed as:

Just as other blocks are grouped by their color<math> E_\theta(\theta, texture and material composition, terrain objects are also grouped in a similar fashion. Before you can generate or import a new terrain object, first you have to define a terrain group and specify its color\phi) \approx j\eta_0 I_0 \frac{e^{-jk_0 r}}{2\pi r} \left[ \frac{\text{cos} \left( \frac{k_0 L}{2} \text{cos} \theta \right) - \text{cos} \left( \frac{k_0 L}{2} \right) }{\text{sin}\theta} \right] </texture and material properties. To define a new terrain group, follow these steps:math>

* Right click on the '''Terrain''' item in the Navigation Tree and select '''Insert New Terrain...''' A dialog for setting up the terrain properties opens up offering a of preloaded material type (Rock) with predefined green color and no texture.* Specify a name for the terrain group and select a color or texture.* Similar to other blocks, you have to specify the material properties, Permittivity (ε<submath>r</sub>) and Electric Conductivity E_\phi(σ\theta,\phi), of te terrain group. Rock with ε<sub>r\approx 0 </submath> = 5 and σ = 0.005S/m is the default material choice for a new terrain.* Click the '''OK''' button of the dialog to accept the changes and close it.

[[File:PROP16where k₀ = 2&pi;/&lambda;₀ is the free-space wavenumber, &lambda;₀ is the free-space wavelength, &eta;₀ = 120&pi; &Omega; is the free-space intrinsic impedance, I₀ is the current on the dipole, and L is the length of the dipole.png]]

Figure 1The directivity of the dipole antenna is given be the expression: Propagation Module's Terrain dialog.

You can change the properties of a terrain surface group from its property dialog. Click on the table that list the properties to select and highlight a row. Then, click the '''Add<math> D_0 \approx \frac{2}{F_1(k_0L) + F_2(k_0L) + F_3(k_0L)} \left[ \frac{\text{cos} \left( \frac{k_0 L}{2} \text{cos} \theta \right) - \text{cos} \left( \frac{k_0 L}{2} \right) }{\text{sin}\theta} \right]^2 </Edit'''button to open up the &quot;Edit Layer&quot; dialog, which is identical to the case of impenetrable surfaces. You can also use EM.Cube's Material List, which will be explained later. When a new terrain type is created, its node on the Navigation Tree becomes active. Under this node you can create and add new terrain objects. When a terrain node is active for drawing, all CAD object creation tools are disabled. You have three options for creating a new terrain object, which will be described in detail in the next sections of this manual:math>

<math> F_1(x) == Using Terrain Generator ==\gamma + \text{ln}(x) - C_i(x) </math>

EM.Cube provides a convenient and powerful Terrain Generator for creating a variety of terrain surface objects. EM.Cube's Terrain Generator looks very similar to CubeCAD's Surface Generator. However, whereas the Surface Generator creates a generic or polymesh surface object, Terrain Generator always creates another special type of object known as a '''Tessellated Object'''. A terrain object is much simpler than EM.Cube's polymesh objects and is usually made up of triangular or quadrilateral facets. As such, terrain objects have limited editing capabilities. For example, you can cut, copy, paste, translate or rotate  terrain objects. But operations like scaling, mirroring, grouping <math> F_2(compositex), arraying, exploding, linking or Boolean operations do not work on terrain objects.= \frac{1}{2} \text{sin}(x) \left[ S_i(2x) - 2S_i(x) \right] </math>

In all of the above models, you can set the height of the surface object to a any desired valuewhere &gamma; = 0. You set 5772 is the lateral extents of the surface and its resolution along the X and Y directions in the boxes labeled '''Range Start'''Euler-Mascheroni constant, '''Range Stop''' and '''Range Step'''. The step values along the X C_i(x) and Y directions S_i(x) are a measure of surface smoothness: the smaller the step valuescosine and sine integrals, the higher the resolution and the smoother the resulting terrain object.respectively:

Some surface types have an additional shape factor called '''Alpha''' that is identical to the alpha parameter in the surface generator. For example, a Gaussian Hump is defined as exp(-r<supmath>2</sup>/S_i(2α²x)), where r is the polar radius. For a Super-quadratic Hump, the input parameter α defines the degree of the super-quadratic surface. α = 2 corresponds to an ellipsoid. Larger values of α get close to a rectangular base with rounded corners. An undulated sinusoidal surface is defined by cos(παx/D_{\int_{0}^{x})*cos(παy/D_y), and an undulated sinc is defined by D_x*D_y*} \frac{ \text{sin(παx/D_x)*sin(παy/D_x)/(2πxy), where D_x and D<sub>y} \tau}{\tau} d\tau </submath> are the X and Y dimensions, respectively. Terrain Generator creates a unit cell based on the specified surface type. From the same dialog, you can also produce an array arrangement of such unit cells. Simply enter any number of elements along the X and Y directionsin the boxes labled '''Array'''.

Figure 2: A 4 × 4 array of hill terrain objects. You can define any arbitrary surface by entering an equation of In the two variables x and y as z = f(x,y). In this case, you have to select the '''Custom Function''' option in the dropdown list labeled '''Model'''. You should enter your equation as any mathematical expression in the box labeled '''Function f(x,y)'''. You can use any of EM.Cube's mathematical functions listed in the '''Function Dialog'''or combine several of them. Note that after selecting the custom function optiona half-wave dipole, the height of the surface is determined by your equationL = &lambda;₀/2, and the '''Height''' box is disabledD₀ = 1. You can also introduce random noise and create a rough terrain643. You can do this by setting a nonzero value for '''Noise'''Moreover, which represent the RMS peak-to-valley amlitude input impedance of the surface roughness. The figures below show two custom terrain surfaces modeled by the equation z dipole antenna is Z_A = (x 73 + j42.y)/20 defined over the range [0, 10] in both X and Y directions5 &Omega;. Random noise has been added These dipole radiators are connected via 50&Omega; transmission lines to both surfacesa 50&Omega; source or load. Therefore, with there is always a certain level of impedance mismatch that violates the noise amplitude being 0.2 and 0.5 conjugate match condition for the left and right figures, respectivelymaximum power.

<tbody><tr class="odd"><td align="left">[[File:PROP21Dipole radiators.png]]</td><td align="left">[[File:PROP20|thumb|720px|EM.Terrano's native half-wave dipole transmitter and receiver.png]]</td>

Figure 3: Two noisy custom terrain surfaces both On the other hand, we you specify a user-defined as z = (x.y)antenna pattern for the transmitter or receiver sets, you import a 3D radiation pattern file that contains all the values of E<sub>&theta;</20: sub> and E_&phi; for all the combinations of (Left&theta;, &phi;) RMS noise amplitude = 0angles.2Besides the three native dipole radiators, (right) RMS noise amplitude = 0[[EM.5Cube]] also provides 3D radiation pattern files for three X-, Y- and Z-polarized half-wave resonant dipole antennas.These pattern data were generated using a full-wave solver like [[EM.Libera]]'s wire MOM solver. The names of the radiation pattern files are:

Every time you create a new terrain object using Terrain Generator, an ASCII data file named &quot;GeneratedTerrain&quot; with a &quot;'''.TRN'''&quot; file extension is created and placed they are located in the folder "\Documents\EMAG\Models" on your project foldercomputer. This is EMNote that these are full-wave simulation data and do not involve any approximate assumptions.Cube's simple To use these files as an alternative to the native terrain file format that basically lists all the (xdipole radiators, y, z) coordinates of you need to select the generated surface points on a horizontal, rectangular XY grid. Terrain Generator simply takes your custom function definition or one of '''User Defined Antenna Pattern''' radio button as the selected catalog surface types and generates the digital elevation data on radiator type in the specified gridtransmitter or receiver set property dialog.  

Another type of terrain model that the terrain generator provides is '''XY Grid Data'''. In this case, you define a rectangular XY grid with a uniform grid cell size along the X and Y directions and manually define the Z-elevation for each grid point. This is similar to the surface generator's &quot;2D Uniform Grid&quot; model type in CubeCAD. Based === A Note on your input to '''Range Start''', '''Range Stop''' and '''Range Step''' along X and Y, a 2D grid is set up and displayed in a table at the bottom Rotation of the terrain generator dialog. By default, all the Z-elevations are set to zero initially. You can click on each table cell and overwrite it with a new value. At the end, click the '''Create''' button of the dialog to add the new grid-based terrain object to the Navigation Tree.Antenna Radiation Patterns ===

[[FileEM.Terrano's Transmitter Set dialog and Receiver Set dialog both allow you to rotate an imported radiation pattern. In that case, you need to specify the '''Rotation''' angles in degrees about the X-, Y- and Z-axes. It is important to note that these rotations are performed sequentially and in the following order:manualsfirst a rotation about the X-axis, then a rotation about the Y-axis, and finally a rotation about the Z-axis. In addition, all the rotations are performed with respect to the "rotated" local coordinate systems (LCS). In other words, the first rotation with respect to the local X-axis transforms the XYZ LCS to a new primed X<sup>&prime;</emagwaresup>Y<sup>&prime;</emcubesup>Z<sup>&prime;</modulessup> LCS. The second rotation is performed with respect to the new Y<sup>&prime;</propagationsup>-axis and transforms the X<sup>&prime;</terrainsup>Y<sup>&prime;</generatingsup>Z^&prime; LCS to a new double-and-exporting-grid-based-terrainprimed X<sup>&prime;&prime;</terrain10_tnsup>Y^{&prime;&prime;}Z^{&prime;&prime;} LCS. The third rotation is finally performed with respect to the new Z^{&prime;&prime;}-axis. The figures below shows single and double rotations.png]]

A grid<table><tr><td> [[File:PROP22B.png|thumb|300px|The local coordinate system of a linear dipole antenna.]] </td><td> [[File:PROP22C.png|thumb|600px|Rotating the dipole antenna by +90&deg; about the local Y-axis.]] </td></tr></table><table><tr><td> [[File:PROP22D.png|thumb|720px|Rotating the dipole antenna by +90&deg; about the local X-axis and then by -45&deg; by the local Y-based terrain objectaxis.]] </td></tr></table>

== Importing &amp; Exporting = Adjustment of Tx/Rx Elevation above a Terrain Models Surface ===

You can import two types of When your transmitters or receivers are located above a flat terrain in EM.Cube's Propagation Module. The first type is &quot;'''.TRN&quot;''' terrain filelike the global ground, which their Z-coordinates are equal to their height above the ground, as the terrain elevation is EMfixed and equal to zero everywhere.Cube's native In many propagation modeling problems, your transmitters and receivers may be located above an irregular terrain formatwith varying elevation across the scene. It is In that case, you may want to place your transmitters or receivers at a basic digital elevation map with a very simple ASCII data file formatcertain height above the underlying ground. The resolution The Z-coordinate of a transmitter or receiver is now the sum of the terrain map in elevation at the X base point and Y directions is the specified in meters as STEPSheight. The (x, y, z) coordinates of EM.Terrano gives you the option to adjust the transmitter and receiver sets to the terrain points are then listed one point per lineelevation. The other type of terrain format supported by EM.Cube This is done for individual transmitter sets and individual receiver sets. At the standard top of the Transmitter Dialog there is a check box labeled &quot;'''7.5min DEMAdjust Tx Sets to Terrain Elevation''' file format with &quot;. Similarly, at the top of the Receiver Dialog there is a check box labeled &quot;'''.DEMAdjust Rx Sets to Terrain Elevation''' file extension&quot;. These boxes are unchecked by default. As a result, your transmitter sets or receiver sets coincide with their associated base points in the project workspace. If you check these boxes and place a transmitter set or a receiver set above an irregular terrain, the transmitters or receivers are elevated from the location of their associated base points by the amount of terrain elevation as can be seen in the figure below. 

To import an external terrain modelbetter understand why there are two separate sets of points in the scene, first you have note that a point array (CAD object) is used to create a terrain group node in uniformly spaced base set. The array object always preserves its grid topology as you move it around the Navigation Treescene. Right click on However, the name of transmitters or receivers associated with this point array object are elevated above the irregular terrain group in the Navigation Tree and select either '''Import Terrainno longer follow a strictly uniform grid...''' or '''Import DEM File...''' A standard Windows '''Open Dialog''' opens up, with If you move the file type base set from its original position to .TRN or .DEM extensionsa new location, respectively. You can browse your folders and find the right base points' topology will stay intact, while the associated transmitters or receivers will be redistributed above the terrain model file to importbased on their new elevations.

You can also export all the terrain objects in the project workspace as a terrain file with a '''<table><tr><td> [[Image:PROP MAN8.TRN''' file extension. You can even import a DEM terrain model from an external file png|thumb|left|640px|A transmitter (red) and then save and export it as as a native terrain grid of receivers (.TRNyellow) file. To export the adjusted above a plateau terrain, select '''File''' &gt; '''Export...''' from Propagation Module's '''File Menu'''surface. The standard Windows Save Dialog opens up withthe default file type set to '''.TRN'''. Type in a name for your new terrain file underlying base point sets (blue and click the '''Save''' button to export orange dots) associated with the adjusted transmitters and receivers on the terrain dataare also visible in the figure.]] </td></tr></table>

[[File:manuals/emagware/emcube/modules/propagation/terrain/importing-external-terrain/prop_manual-12_tn== Discretizing the Propagation Scene in EM.png]]Terrano ==

Most of the timeIn many practical scenarios, however, your outdoor propagation scene consists of simple buildings made of single-layer walls with standard material properties (ε_r and σ)may have curved surfaces, or the terrain may be irregular. In the case EM.Terrano allows you to draw any type of a single-layer impenetrable surfaceor solid geometric objects such as cylinders, the specular interface is an infinite dielectric half-spacecones, which reflects the impinging raysetc. Single-layer under impenetrable and penetrable surface groups or penetrable surfaces, on the other hand, involve finite-thickness dielectric walls, which both reflect and transmit the incident raysvolumes. Similarly, most EM.Terrano's mesh generator creates a triangular surface mesh of all the objects in your indoor propagation scenes involve simple single-layer penetrable walls with the specified material properties ε_r and σ. A thin wall acts like scene, which is called a finite-thickness dielectric slab that both reflects and transmits incident raysfacet mesh. In Even the case walls of the global ground or terrain cubic buildings are meshed using triangular cells. This enables EM.Terrano to properly discretize composite buildings made of conjoined cubic objects, only ray reflection off the ground surface is considered.

In Unlike [[EM.Cube]]'s Propagation Moduleother computational modules, you can define multilayer surfaces with both reflection and transmission properties. You can define multilayer impenetrable buildings, multilayer penetrable walls, and multilayer terrain, with an arbitrary number the density or resolution of layers having different material compositionsEM. You define a multilayer Terrano's surface mesh does not depend on the operating frequency and is not expressed in terms of the property dialog wavelength. The sole purpose of a block, whether impenetrable, penetrable or terrainEM. In the section entitled '''Surface Type''', two options are available: '''Standard Material''' or '''User Defined Model''Terrano's facet mesh is to discretize curved and irregular scatterers into flat facets and linear edges. For simple multilayer wallsTherefore, select geometrical fidelity is the '''Standard Material''' optiononly criterion for the quality of a facet mesh. You can add new layers with arbitrary thickness and material parameters It is important to the existing layers. To insert note that discretizing smooth objects using a triangular surface mesh typically creates a new layer, deselect any items in large number of small edges among the layer list, facets that are simply mesh artifacts and click the '''Add/Edit''' button to open the &quot;Add Layer&quot; Dialogshould not be considered as diffracting edges. Here you can enter For example, each rectangular face of a name for cubic building is subdivided into four triangles along the new layer and values for its '''Thickness''', ε_r and σtwo diagonals. You may also delete any layer by selecting and highlighting it and clicking The four internal edges lying inside the '''Delete''' buttonface are obviously not diffracting edges. You can move layers up or down using A lot of subtleties like these must be taken into account by the '''Move Up''' SBR solver to run accurate and '''Move Down''' buttons and change the layer hierarchycomputationally efficient simulations.

You can also search EM.Cube's material database by clicking === Generating the '''Material'''button of &quot;Add Layer&quot; or &quot;Edit Layer&quot; dialogs. This opens the '''Materials'''Dialog. Inside the material list select and highlight any row and click the '''OK''' button. The selected material will fill out all the fields in the &quot;Add Layer&quot; or &quot;Edit Layer&quot; dialogs. Inside the Materials Dialog, you can type the few first letters of any material, and it will take you to the corresponding row of the list.Facet Mesh ===

[[File:PROP26You can view and examine the discretized version of your scene's objects as they are sent to the SBR simulation engine. You can adjust the mesh resolution and increase the geometric fidelity of discretization by creating more and finer triangular facets. On the other hand, you may want to reduce the mesh complexity and send to the SBR engine only a few coarse facets to model your buildings. The resolution of EM.Terrano's facet mesh generator is controlled by the '''Cell Edge Length''' parameter, which is expressed in project length units. The default mesh cell size of 100 units might be too large for non-flat objects. You may have to set a smaller cell edge length in EM.Terrano's Mesh Settings dialog, along with a lower curvature angle tolerance value to capture the curvature of your curved structures adequately.png]]

Figure 1<table><tr><td> [[Image:Propagation Moduleprop_manual-29.png|thumb|left|480px|EM.Terrano's Penetrable Surface Dialog showing a three-layer wall compositionmesh settings dialog.]] </td></tr></table>

[[FileImage:PROP24Info_icon.png|30px]]Click here to learn more about '''[[Preparing_Physical_Structures_for_Electromagnetic_Simulation#Working_with_EM.Cube.27s_Mesh_Generators | Working with Mesh Generator]]'''.

Figure 2[[Image: EMInfo_icon.png|30px]] Click here to learn more about the properties of '''[[Glossary_of_EM.Cube%27s_Simulation-Related_Operations#Facet_Mesh | EM.Terrano's material listFacet Mesh Generator]]'''.

When you start a new project == Running Ray Tracing Simulations in EM.Cube's Propagation Module and draw a solid object like a box in the project workspace without having defined any surface groups, it is assumed to be of the impenetrable surface type. A default impenetrable surface group called Block_1 is automatically added to the Navigation Tree, which holds your newly drawn object. The default group has the material properties of &quot;Brick&quot; (ε_r Terrano = 4.4 and σ = 0.001 S/m.) with a dark brown color. You can continue drawing new objects in the project workspace and adding them under this block node. Or you can define a new surface type with different properties. By default, the last surface group that was defined is '''Active'''. The current active surface group is always listed in bold letters in the Navigation Tree. When you draw a new object, it is always inserted under the current active surface group. Any surface group can be activated by right clicking its name in the Navigation Tree and selecting the '''Activate''' item of the contextual menu.

You can move any object from its current surface group into any other available surface group. First select the object, then right click on its surface and select '''MoveTo &gt; Propagation &gt;'''. A submenu appears which lists all the available surface groups where you can transfer the selected object. You can also move objects among surface groups by selecting their names in the Navigation Tree and using the contextual menu. In a similar way, you can transfer objects from Propagation Module to EM.Cube's other modules or vice versa. '''Keep in mind that all the external model files such as STEP, IGES, STL, etc. are first imported to EM.Cube's CubeCAD, from which you can transfer them to other modules.''' First select the object, then right click and select '''MoveTo &gt;'''. In the submenu you will see Terrano provides a list number of all the EM.Cube modules that have at least one available group where you can transfer your selected object. You can select multiple objects for transfer. When using the keyboard's '''Shift Key''' different simulation or '''Ctrl Key''' for multiple selection, make sure that those keys are held down, when you right click to access the contextual menu.solver types:

Like every other electromagnetic solver, EM.Cube's SBR ray tracer requires a source for excitation and one or more observables for generation of simulation data. EM.Cube's new Propagation Module offers several types of sources and observables for === Running a Single-Frequency SBR simulation. You can mix and match different source types and observable types depending on the requirements of your modeling problem. There are two types of sources:Analysis ===

There are four types * Set the units of your project and the frequency of operation. Note that the default project unit is '''millimeter'''. Wireless propagation problems usually require meter, mile or kilometer as the project unit.* Create the blocks and draw the buildings at the desired locations.* Keep the default ray domain and accept the default global ground or change its material properties.* Define an excitation source and observables:for your project.* If you intend to use transmitters and receivers in your scene, first define the required base sets and then define the transmitter and receiver sets based on them.* Run the SBR simulation engine.* Visualize the coverage map and plot other data.

# Receiver# Field Sensor# Far Field - Radiation Pattern# Huygens Surface The simplest SBR simulation You can be performed using a short dipole source with a specified field sensor plane. In this way, access EM.Cube computes the electric and magnetic fields radiated Terrano's Simulation Run dialog by your dipole source in clicking the presence of your multipath propagation environment'''Run''' [[File:run_icon. A &quot;classic&quot; urban propagation scene can be set up using a &quot;Transmitter&quot; source and an array png]] button of the '''Simulate Toolbar''' or by selecting '''Simulate &quot;Receiver&quotrarr; observablesRun. A transmitter is a point radiator with a user defined radiation pattern. A receiver is a polarization-matched isotropic point radiator that collects .''' or using the received rays at its aperturekeyboard shortcut {{key|Ctrl+R}}. Using receivers, When you can calculate click the {{key|Run}} button, a new window opens up that reports the received power coverage map different stages of your propagation scenethe SBR simulation and indicates the progress of each stage. You can also calculate your channel's path loss between After the transmitter SBR simulation is successfully completed, a message pops up and all prompts the completion of the receiversprocess. <br />   == Hertzian Dipole Sources ==

<tbodytr><tr class="odd"td> [[Image:Terrano L1 Fig16.png|thumb|left|480px|EM.Terrano's simulation run dialog.]] </td>

<tbody><tr class="odd"><td align="left">[[FileImage:PROP19(1)PROP MAN10.png]]</td><td align="|thumb|left">[[File:PROP20(1)|550px|EM.Terrano's output message window.png]]</td>

Figure 1: Propagation Module's Transmitter dialog with a user defined radiator selected. == Multiple Transmitters vs. Antenna Arrays == EM.Cube's SBR simulations are fully coherent and 3D-polarimetric. This means that Changing the phase and polarization of all the rays are maintained and processed during their bounces in the scene. Your propagation scene can have more than one transmitter. During an SBR simulation, all the rays emanating from all the transmitters are traced in the propagation scene. All the received rays at a given receiver location are summed coherently and vectorially. This is based on the principle of linear superposition. All the transmitters belonging to the same transmitter set have the same radiation properties. They are either parallel short dipole radiators with the same current amplitudes and phases, or parallel user defined radiators with identical radiation patterns. As these transmitters are placed at different spatial locations, they effectively form an antenna array with identical elements. The array factor is simply determined by the coordinates of the base points. If you want to have different amplitude or phases, then you need to define different transmitter sets. If that radiators are indeed the elements of an actual antenna array with a half wavelength spacing or so, we recommend that you import the radiation pattern of the array structure instead and replace the whole multi-radiator system with a single point transmitting radiator in your propagation scene. This case is usually encountered in MIMO systems, and using an equivalent point transmitter is an acceptable approximation because the total size of the array aperture is usually much smaller than the dimensions of your propagation scene and its representative length scales. In that case, you need to position the equivalent point radiator at the radiation center of the antenna array. This depends on the physical structure of the antenna array. However, keep in mind that any reasonable guess may still provide a good approximation without any significant error in the received ray data.     =Engine Settings = Defining Receiver Sets ==

Receivers act as observables in There are a propagation scene. The objective number of a SBR simulation is to calculate the far-zone electric fields settings that can be accessed and the total received power at changed from the location of a receiverRay Tracing Engine Settings Dialog. In that senseTo open this dialog, receivers indeed act as field observation pointsclick the button labeled {{key|Settings}} on the right side of the '''Select Simulation or Solver Type''' drop-down list in the Run Dialog. You need EM.Terrano's SBR simulation engine allows you to define at least one receiver in separate the scene before you can run physical effects that are calculated during a SBR simulationray tracing process. You define can selectively enable or disable '''Reflection/Transmission''' and '''Edge Diffraction''' in the receivers "Ray-Block Interactions" section of this dialog. By default, ray reflection and transmission and edge diffraction effects are enabled. Separating these effects sometimes help you better analyze your propagation scene by associating them with and understand the base sets you have already defined impact of various blocks in the project workspace. Unlike transmitters that usually one or few, a typical propagation scene may involve a large number of receivers. To generate a wireless coverage map, you need to define an array of points as your base set.    

To define EM.Terrano allows a new Receiver Set, go to the Observables section finite number of ray bounces for each original ray emanating from a transmitter. This is very important in situations that may involve resonance effects where rays get trapped among multiple surfaces and may bounce back and forth indefinitely. This is set using the Navigation Tree, right click on the box labeled &quot;'''Receivers''' item and select '''Insert Receiver..Max No.Ray Bounces''' A dialog opens up that contains &quot;, which has a default name for value of 10. Note that the maximum number of ray bounces directly affects the new Receiver Set computation time as well as the size of output simulation data files. This can become critical for indoor propagation scenes, where most of the rays undergo a dropdown list labeled large number of reflections. Two other parameters control the diffraction computations: '''Select Radiator SetMax Wedge Angle''' in degrees and '''Min Edge Length'''. In this list you will see all the available base sets that you have already define in the project workspaceunits. Select and designate The maximum wedge angle is the desired base set as the receiver set. Note angle between two conjoined facets that if the base set contains more than one point, all of is considered to make them are designated as receiversalmost flat or coplanar with no diffraction effect. After defining a receiver set, The default value of the points change their color to the receiver color, which maximum wedge angle is yellow by default170&deg;. The first element of the set minimum edge length is represented by a larger ball size of the same color indicating common edge between two conjoined facets that it is the selected receiver in the sceneconsidered as a mesh artifact and not a real diffracting edge. The Receiver Set Dialog is also used to access individual receivers default value of the set for data visualization at the end of a simulation. At the end of an SBR simulation, the button labeled &quot;Show Ray Data&quot; becomes enabled. Clicking this button opens the Ray Data Dialog, where you can see a list of all the received rays at the selected receiver and their computed characteristicsminimum edge length is one project units.   

<tbody><tr class="odd"><td align="left">[[FileImage:PROP21(1)PROP MAN11.png]]</td><td align="|thumb|left">[[File:PROP22|720px|EM.Terrano's SBR simulation engine settings dialog.png]]</td>

Figure 1: Propagation ModuleAs rays travel in the scene and bounce from surfaces, they lose their power, and their amplitudes gradually diminish. From a practical point of view, only rays that have power levels above the receiver sensitivity can be effectively received. Therefore, all the rays whose power levels fall below a specified power threshold are discarded. The 's Receiver dialog''Ray Power Threshold''' is specified in dBm and has a default value of -150dBm. Keep in mind that the value of this threshold directly affects the accuracy of the simulation results as well as the size of the output data file.

As an asymptotic electromagnetic field solver, the SBR simulation engine can compute the electric and magnetic field distributions in EM.Terrano gives a specified plane. In order to view these field distributions, you must first define field sensor observables before running few more options for the SBR simulation. To do that, right click on the '''Field Sensors'''item in the '''Observables''' section ray tracing solution of the Navigation Tree and select '''Insert New Observableyour propagation problem...'''. The Field Sensor Dialog opens up. At the top of the dialog and in the section titled '''Sensor Plane Location'''For instance, first it allows you need to set exclude the plane direct line-of field calculation. In -sight (LOS) rays from the dropdown final solution. There is a check box for this purpose labeled '''Direction''', you have three options X, Y, and Z, representing "Exclude direct (LOS) rays from the&quot;normals&quot; to the XYsolution", YZ and ZX planes, resepctively. The which is unchecked by default direction is Z, i.eEM. XY plane parallel Terrano also allows you to superpose the substrate layersreceived rays incoherently. In the three boxes lebeled '''Coordinates'''that case, you set the coordinates powers of the center of the planeindividual ray are simply added to compute that total received power. Then, you specify the '''Size'''of the plane This option in project units, and finally set the '''Number of Samples'''along the two sides of the sensor plane. The larger the number of samplescheck box labeled "Superpose rays incoherently" is disabled by default, the smoother the near field map will appeartoo. 

In At the section titled Output Settingsend of a ray tracing simulation, you can also select the electric field map type from two options: '''Confetti''' of each individual ray is computed and '''Cone'''reported. The former produces an intensity plot for field amplitude and phaseBy default, while the latter generates a 3D vector plot. In actual received ray fields are reported, which are independent of the radiation pattern of the confetti case, you have an option to receive antennas. EM.Terrano provides a check the box labeled "Normalize ray'''Data Interpolation'''s E-field based on receiver pattern", which creates a smooth and blended (digitally filtered) mapis unchecked by default. In the cone caseIf this box is checked, you can set the size of the vector cones that represent the field direction. At the end of a sweep simulation, multiple field map are produced and added each ray is normalized so as to reflect that effect of the Navigation Tree. You can animate these maps. However, during the sweep only one field type is stored, either the E-field or H-field. You can choose the field type for multiple plots using the radio buttons in the section titled '''Field Display - Multiple Plots''receiver antenna's radiation pattern. The default choice received power of each ray is calculated from the E-field.   following equation:

Figure 1: Propagation ModuleIt can be seen that if the ray's Field Sensor dialogE-field is not normalized, the computed ray power will correspond to that of a polarization matched isotropic receiver.

[[File:PMOM88In a 3D SBR simulation, a transmitter shoots a large number of rays in all directions. The electric fields of these rays are polarimetric and their strength and polarization are determined by the designated radiation pattern of the transmit antenna. The rays travel in the propagation scene and bounce from the ground and buildings or other scatterers or get diffracted at the building edges until they reach the location of the receivers. Each individual ray has its own vectorial electric field and power. The electric fields of the received rays are then superposed coherently and polarimetrically to compute the total field at the receiver locations. The designated radiation pattern of the receivers is then used to compute the total received power by each individual receiver.png]]

== Computing Radiation Patterns From a theoretical point of view, the radiation patterns of the transmit and receive antennas are independent of the propagation channel characteristics. For the given locations of the point transmitters and receivers, one can assume ideal isotropic radiators at these points and compute the polarimetric transfer function matrix of the propagation channel. This matrix relates the received electric field at each receiver location to the transmitted electric field at each transmitter location. In SBR ==general, the vectorial electric field of each individual ray is expressed in the local standard spherical coordinate system at the transmitter and receiver locations. In other words, the polarimetric channel matrix expresses the '''E_&theta;''' and '''E_&phi;''' field components associated with each ray at the receiver location to its '''E_&theta;''' and '''E_&phi;''' field components at the transmitter location. Each ray has a delay and &theta; and &phi; angles of departure at the transmitter location and &theta; and &phi; angles of departure at the receiver location.

Coming SoonTo perform a polarimatric channel characterization of your propagation scene, open EM.Terrano's Run Simulation dialog and select '''Channel Analyzer''' from the drop-down list labeled '''Select Simulation or Solver Type'''.At the end of the simulation, a large ray database is generated with two data files called "sbr_channel_matrix.DAT" and "sbr_ray_path.DAT". The former file contains the delay, angles of arrival and departure and complex-valued elements of the channel matrix for all the individual rays that leave each transmitter and arrive at each receiver. The latter file contains the geometric aspects of each ray such as hit point coordinates.

= Scene Discretization &amp; Adjustment == The "Near Real-Time" Polarimatrix Solver ===

== After EM.Terrano's channel analyzer generates a ray database that characterizes your propagation channel polarimetrically for all the combinations of transmitter and receiver locations, a ray tracing solution of the propagation problem can readily be found in almost real time by incorporating the effects of the radiation patterns of transmit and receive antennas. This is done using the '''Polarimatrix Solver''', which is the third option of the drop-down list labeled '''Select Simulation or Solver Type''' in EM.Terrano's Run Simulation dialog. The Need For Discretization Of Propagation Scene ==results of the Polarimatrix and 3D SBR solvers must be identical from a theoretical point of view. However, there might be small discrepancies between the two solutions due to roundoff errors.

In Using the Polarimatrix solver can lead to a typical SBR simulation, a ray is traced from the location significant reduction of the source until it hits a scatterer. The SBR method assumes total simulation time in sweep simulations that the ray hits either involve a flat facet large number of the scatterer or one of its edges. In the case of hitting a flat facet, the specular point is used to launch new reflected transmitters and transmitted raysreceivers. The surface Certain simulation modes of the facet is treated as an infinite dielectric medium interface, at which the reflection and transmission coefficients are calculatedEM. In the case of hitting an edge, new diffracted rays Terrano are generated in intended for the scene. However, Polarimatrix solver only those who reach a nearby receiver as will be described in their line of sight are ever taken into account. In other words, diffractions are treated locallythe next section.

EM.Cube's Propagation Module allows you {{Note| In order to draw any type of surface or solid CAD objects under impenetrable and penetrable surface groups. Some of these objects have flat faces such as boxesuse the Polarimatrix solver, pyramids, rectangle or triangle strips, etc. Some others contain curved surfaces or curved boundaries such as cylinders, cones, etc. All the non-flat surfaces have to be discretized in the form of you must first generate a collection of smaller flat facets. EM.Cube uses a triangular surface mesh generator to discretize the penetrable and impenetrable surface objects ray database of your propagation scene. This mesh generator is very similar to the ones used in using EM.CubeTerrano's two other modules: MoM3D and Physical Optics (PO)Channel Analyzer. }}

You can build a variety of surface and solid objects using === EM.CubeTerrano's native &quot;Curve&quot; CAD objects like lines, polylines, circles, etc. You can use tools like Extrude, Loft, Strip-Sweep, Pipe-Sweep, etc. to transform curves into surface or solid objects. '''However, keep in mind that all the &quot;Curve&quot; CAD objects are ignored by the SBR mesh generator and are therefore not sent to the simulation engine.'''Simulation Modes ===

You can view and examine {| class="wikitable"|-! scope="col"| Simulation Mode! scope="col"| Usage! scope="col"| Which Solver?! scope="col"| Frequency ! scope="col"| Restrictions|-| style="width:120px;" | [[#Running a Single-Frequency SBR Analysis | Single-Frequency Analysis]]| style="width:180px;" | Simulates the discretized version of your propagation scene objects as they are sent to the "As Is"| style="width:150px;" | SBR simulation engine. To view the mesh, click Channel Analyzer, Polarimatrix, Radar Simulator| style="width:120px;" | Runs at the '''Mesh''' [[Filecenter frequency fc| style="width:manuals/emagware/emcube/modules/propagation/hybrid-simluations/illuminating300px;" | None|-periodic-walls-using-sbr/mesh_tool| style="width:120px;" | [[Parametric_Modeling_%26_Simulation_Modes_in_EM.pngCube#Running_Frequency_Sweep_Simulations_in_EM.Cube | Frequency Sweep]] button of the Simulate Toolbar or select '''Simulate &gt| style="width:180px; Discretization &gt; Show Mesh''', or use " | Varies the keyboard shortcut '''Ctrl+M'''. A triangular surface mesh operating frequency of your physical structure appears in the project workspace. In this caseray tracer | style="width:150px;" | SBR, EM.Cube enters it mesh view mode. You can perform view operations like rotate viewChannel Analyzer, panPolarimatrix, zoom, etc. But you cannot select objects, or move them or edit their properties. To get out Radar Simulator| style="width:120px;" | Runs at a specified set of the Mesh View and return to EMfrequency samples| style="width:300px;" | None|-| style="width:120px;" | [[Parametric_Modeling_%26_Simulation_Modes_in_EM.Cube's Normal View, press #Running_Parametric_Sweep_Simulations_in_EM.Cube | Parametric Sweep]]| style="width:180px;" | Varies the '''Esc Key''' value(s) of one or more project variables| style="width:150px;" | SBR| style="width:120px;" | Runs at the keyboardcenter frequency fc| style="width:300px;" | Requires definition of sweep variables, works only with SBR solver as the physical scene may change during the sweep |-| style="width:120px;" | [[#Transmitter_Sweep | Transmitter Sweep]]| style="width:180px;" | Activates two or click more transmitters sequentially with only one transmitter broadcasting at each simulation run | style="width:150px;" | Polarimatrix| style="width:120px;" | Runs at the Mesh button of center frequency fc| style="width:300px;" | Requires at least two transmitters in the Simulate Toolbar once againscene, or go works only with Polarimatrix solver and requires an existing ray database|-| style="width:120px;" | [[#Rotational_Sweep | Rotational Sweep]]| style="width:180px;" | Rotates the radiation pattern of the transmit antenna(s) sequentially to model beam steering | style="width:150px;" | Polarimatrix| style="width:120px;" | Runs at the Simulate Menu center frequency fc| style="width:300px;" | Works only with Polarimatrix solver and deselect requires an existing ray database|-| style="width:120px;" | [[#Mobile_Sweep | Mobile Sweep]]| style="width:180px;" | Considers one pair of active transmitter and receiver at each simulation run to model a mobile communication link| style="width:150px;" | Polarimatrix| style="width:120px;" | Runs at the '''Discretization &gtcenter frequency fc| style="width:300px;''' '''Show Mesh''' item." | Requires the same number of transmitters and receivers, works only with Polarimatrix solver and requires an existing ray database|}

You can adjust the mesh resolution and increase the geometric fidelity of discretization by creating more and finer triangular facets. On the other hand, you may want to reduce the mesh complexity and send to the SBR engine only a few coarse facets to model your buildings. To adjust the mesh resolution, open the Mesh Settings Dialog by clicking the '''Mesh Settings''' [[File:manuals/emagware/emcube/modules/propagation/discretizing-the-scene/customizing-prismatic-mesh/mesh_settings.png]] button of the Simulate Toolbar or select '''Simulate &gt; Discretization &gt;''' '''Mesh Settings...'''. This dialog provides a single parameters: '''Edge Length'''., which has a default value of 100 project units. If you are already Click on each item in the Mesh View Mode and open the Mesh Settings Dialog, you can see the effect of changing the edge length using the '''Apply''' button. Click OK above list to close the dialoglearn more about each simulation mode.

Note that unlike You set the simulation mode in EM.CubeTerrano's other computational modules that express simulation run dialog using the default mesh density based on the wavelength, the resolution of the SBR mesh generator drop-down list labeled '''Simulation Mode'''. A single-frequency analysis is expressed in project length unitsa single-run simulation. The default edge length value of 100 units might be too large for nonAll the other simulation modes in the above list are considered multi-flat objectsrun simulations. You may have to use In multi-run simulation modes, certain parameters are varied and a lower value to capture collection of simulation data files are generated. At the curvature end of your curved structures adequatelya sweep simulation, you can plot the output parameter results on 2D graphs or you can animate the 3D simulation data from the navigation tree. 

[[File:manuals/emagware/emcube/modules/propagation/discretizing-{{Note| EM.Terrano's frequency sweep simulations are very fast because thegeometrical optics (ray tracing) part of the simulation is frequency-scene/customizing-prismatic-mesh/prop_manual-29independent.png]]}}

In {{Note| EM.Cube, terrain objects are represented by and saved as special &quot;Tessellated&quot; objects with quadrilateral cells. This is true of terrain objects that you create yourself using EM.CubeTerrano's Terrain Generator as well as all transmitter sweep works only with the terrain objects that you import from external files to your project. The center of each cell represents the terrain elevatioin at that point. Tessellated objects are considered as discretized objects by EM.Cube Polarimatrix Solver and they are not meshed one more time by the SBR mesh generator. Each quadrilateral cell is divided into two trinagular cells before being passed to the SBR simulation engine. Therefore, when requires an existing ray database previously generated using EM.Cube's Terrain Generator to create a new terrain object, you have to pay special atterntion to the resolution of the terrain object as it determines the total number of terrain facets sent to the simulation engine. A high resolution terrain, although looking better and more realistic, may easily lead to an enormous computational problemChannel Analyzer.}}

== You can rotate the 3D radiation patterns of both the transmitters and receivers from the property dialog of the parent transmitter set or receiver set. This is done in advance before a SBR Mesh Rules &amp; Considerations ==simulation starts. You can define one or more of the rotation angles of a transmitter set or a receiver set as sweep variables and perform a parametric sweep simulation. In that case, the entire scene and all of its buildings are discretized at each simulation run and a complete physical SBR ray tracing simulation is carried out. However, we know that the polarimetric characteristics of the propagation channel are independent of the transmitter or receiver antenna patterns or their rotation angles. A rotational sweep allows you to rotate the radiation pattern of the transmitter(s) about one of the three principal axes sequentially. This is equivalent to the steering of the beam of the transmit antenna either mechanically or electronically. The result of the sweep simulation is a number of received power coverage maps, each corresponding to one of the angular samples. To run a rotational sweep, you must specify the rotation angle.

Coming Soon.{{Note| EM.Terrano's rotational sweep works only with the Polarimatrix Solver and requires an existing ray database previously generated using the Channel Analyzer.}}

== Adjusting Block Elevation On Terrain = Mobile Sweep ===

In EM.Cubea mobile sweep, buildings and all other CAD objetcs are initially created on the XY plane by defaulteach transmitter is paired with a receiver according to their indices in their parent sets. In other wordsAt each simulation run, the Z-coordinate of the local coordinate system only one (LCSTx, Rx) of all blocks pair is set considered to zero until you change thembe active in the scene. As long as you use the global grounda result, all is fine as your buildings are seated on the groundgenerated coverage map takes a different meaning implying the sequential movement of the transmitter and receiver pair along their corresponding paths. When your propagation scene has an irregular terrainIn other words, you want to place your buildings on the terrain set of point transmitters and not buried under itthe set of point receivers indeed represent the locations of a single transmitter and a single receiver at different instants of time. Buildings It is obvious that the total number of transmitters and total number of receivers in EM.Cube are not adjusted to the terrain elevation automaticallyscene must be equal. You need to instruct Otherwise, EM.Cube to do soTerrano will prompt an error message.

To update the building positions and adjust their elevation to the underlying terrain, right click on the [[EM.Cube]] provides a '''TerrainMobile Path Wizard''' item of the Navigation Tree and select '''Adjust Scene Elevation''' from the context menu. All the blocks in the scene are automatically elevated in the Z direction such that their bases sit on facilitates the terrain. In effect, all the blocks are translated creation of a transmitter set or a receiver set along the global Z axis by proper amounts such that their local Z coordinate equals the Z-elevation of the underlying terrain objecta specified path.This feature is particularly useful if you change the location of the terrain path can be an existing nodal curve (polyline or NURBS curve) or an existing line objects. You can also import a new terrain after sptial Cartesian data file containing the blocks have been createdcoordinates of the base location points. For more information, refer to [[Glossary_of_EM.Cube%27s_Wizards#Mobile_Path_Wizard | Mobile Path Wizard]].

{{Note: You have to make sure that the resolution of your terrain, its fluctuation scale and building dimensions are all comparable| EM. Otherwise, on a high-resolution,rapidly varying terrain, you will have buildings whose bottoms are in contact Terrano's mobile sweep works only with the terrain only at few points Polarimatrix Solver and parts of them hang in requires an existing ray database previously generated using the airChannel Analyzer.}}

A Scene In a typical SBR ray tracing simulation, EM.Terrano includes all the propagation effects such as direct (LOS) rays, ray reflection and transmission, and edge diffractions. At the end of a SBR simulation, you can visualize the received power coverage map of your propagation scene, which appears under the receiver set item in the navigation tree. The figure below shows the received power coverage map of the random city scene with Buildings a vertically polarized half-wave dipole transmitter located 10m above the ground and Terrain Before a large grid of vertically polarized half-wave dipole receivers placed 1.5m above the ground. The legend box shows the limits of the color map between -23dBm as the maximum and After Adjusting Elevation-150dB (the default receiver sensitivity value) as the minimum.

In EM.Cube, all Sometime it is helpful to change the transmitters and receivers are tied up with point objects in scale of the project workspacecolor map to better understand the dynamic range of the coverage map. These point objects are grouped and organized in base sets. When If you move double-click on the point objects legend or change their coordinates, all of their associated transmitters or receivers immediately follow them to right-click on the new location. For example, you usually define a grid of receivers using a base set that is made up of a uniformly spaced array of points and spread them coverage map's name in your scene. All of these receivers have the same height because their associated base points all have navigation tree and select '''Properties''', the same Z-coordinatePlot Settings dialog opens up. When your receivers are located above a flat terrain like Select the global ground, their Z'''User-coordinates are equal to their height above Defined''' item and set the ground, lower and upper bounds of color map as the terrain elevation is fixed and equal to zero everywhere. The same is true for transmitters, tooyou wish.   

In many propagation modeling problems, your transmitters and receivers may be located above an irregular terrain with varying elevation across the scene. In that case, you may want to place your transmitters or receivers at a certain height above the underlying ground<table><tr><td> [[Image:UrbanCanyon15. png|thumb|left|480px|The Z-coordinate plot settings dialog of a transmitter or receiver is now the sum of the terrain elevation at the base point and the specified heightcoverage map. EM]] </td></tr></table><table><tr><td> [[Image:UrbanCanyon16.Cube gives you the option to adjust the transmitter and receiver sets to the terrain elevation. This is done for individual transmitter sets and individual receiver sets. At the top png|thumb|left|640px|The received power coverage map of the Transmitter Dialog there is random city scene with a check box labeled &quot;'''Adjust Tx Sets to Terrain Elevation'''&quot;. Similarly, at the top of the Receiver Dialog there is a check box labeled &quot;'''Adjust Rx Sets to Terrain Elevation'''&quot;. These boxes are unchecked by default. As a result, your transmitter sets or receiver sets coincide with their associated base points in the project workspace. If you check these boxes user-defined color map scale between -80dBm and place a transmitter set or a receiver set above an irregular terrain, the transmitters or receivers are elevated from the location of their associated base points by the amount of terrain elevation as can be seen in teh figure below-20dBm.   ]] </td></tr></table>

To better understand why there are two separate sets of points in the scenevarious propagation effects, note that a point array (CAD object) is used to create a uniformly spaced base setEM. The array object always preserves its grid topology as Terrano allows you move it around the scene. However, the transmitters to enable or receivers associated with this point array object are elevated above the irregular terrain and no longer follow a strictly uniform griddisable these effects selectively. If you move the base set This is done from its original position to a new location, the base points' topology will stay intact, while the associated transmitters or receivers will be redistributed above Ray Tracing Simulation Engine Settings dialog using the terrain based on their new elevationsprovided check boxes.

<tbody><tr class="odd"><td align="left">[[FileImage:manuals/emagware/emcube/modules/propagation/sources-observables/transmitters-and-receivers-above-an-irregular-terrain/prop_txrx1_tnUrbanCanyon14.png]]</td><td align="|thumb|left">[[File:manuals/emagware/emcube/modules/|640px|EM.Terrano's simulation run dialog showing the check boxes for controlling various propagation/sources-observables/transmitters-and-receivers-above-an-irregular-terrain/prop_txrx2_tneffects.png]]</td>

Figure 1<table><tr><td> [[Image: Transmitters and receivers adjusted above an uneven terrain and their associated base setsUrbanCanyon11. png|thumb|left|640px|The received power coverage map of the random city scene with direct LOS rays only.]] </td></tr><tr><td> [[Image:UrbanCanyon12.png|thumb|left|640px|The received power coverage map of the random city scene with reflected rays only.]] </td></tr><tr><td> [[Image:UrbanCanyon13.png|thumb|left|640px|The received power coverage map of the random city scene with diffracted rays only.]] </td></tr></table>

= Running A SBR = Working with EM.Terrano's Simulation Data ==

== = The Ray Tracing Solvers' Output Simulation Setup Data ===

Both the SBR solver and the Polarimatrix solver perform the same type of simulation but in two different ways. The SBR solver discretizes the scene including all the buildings and terrain, shoots a large number of rays from the transmitters and collects the rays at the receivers. The Polarimatrix solver does the same thing using an existing polarimetric ray database that has been previously generated using EM.CubeTerrano's Propagation Module offers three types Channel Analyzer. It incorporates the effects of the radiation patterns of the transmit and receive antennas in conjunction with the polarimetric channel characteristics. At the end of a ray tracing simulations:simulation, all the polarimetric rays emanating from the transmitter(s) or other sources that are received by the individual receivers are computed, collected, sorted and saved into ASCII data files. From the ray data, the total electric field at the location of receivers as well as the total received power are computed. The individual ray data include the field components of each ray, the ray's elevation and azimuth angles of departure and arrival (departure from the transmitter location and arrival at the receiver location), and time delay of the received ray with respect to the transmitter. If you specify the temperatures, noise figure and transmission line losses in the definition of the receiver sets, the noise power level and signal-to-noise ratio (SNR) at each receiver are also calculated, and so are the E_b/N₀ and bit error rate (BER) for the selected digital modulation scheme.

An SBR analysis In wireless propagation modeling for communication system applications, the received power at the receiver location is more important than the simplest ray tracing simulation and involves field distributions. In order to compute the following stepsreceived power, you need three pieces of information:

# Set the unit * '''Total Transmitted Power (EIRP)''': This requires knowledge of project scene and the frequency of operation. Note that EM.Cube's default project unit is millimeter. When working with the Propagation Modulebaseband signal power, pay attention to the project unit. Radio propagation problems usually require metertransmitter chain parameters, mile or kilometer as the project unit.# Create transmission characteristics of the transmission line connecting the transmitter circuit to the blocks transmitting antenna and draw the buildings at radiation characteristics of the desired locationstransmitting antenna.# Keep the default ray domain and accept the default global ground or change its material properties* '''Channel Path Loss''': This is computed through SBR simulation.# Define * '''Receiver Properties''': This includes the base sets (at least one for radiation characteristics of the transmitter and one for receiving antenna, the receiver).# Define transmission characteristics of the transmitter and receiver(s) using transmission line connecting the available base sets.# Run receiving antenna to the SBR simulation engine.# Visualize receiver circuit and the coverage map and plot other datareceiver chain parameters.

You can access the Propagation Module's run dialog by clicking the '''Run''' [[File:manuals/emagware/emcube/modules/propagation/running-In a-sbr-simulation/simulation-setup/run_icon.png]] button of the '''Simulate Toolbar''' or by selecting '''Simulate &gt; Run...''' or using the keyboard shortcut '''Ctrl+R'''. When you click the '''Run''' buttonsimple link scenario, a new window opens up that reports the different stages of the SBR simulation and indicates the progress of each stage. After the SBR simulation received power P_r in dBm is successfully completed, a message pops up and propmts found from the completion of the process.following equation:

<math> P_r [[File:PROP12.pngdBm]= P_t [dBm]+ G_{TC} + G_{TA} - PL + G_{RA} + G_{RC} </math>

Figure 1: Propagation Module's Simulation Run dialogwhere P_t is the baseband signal power in dBm at the transmitter, G_TC and G_RC are the total transmitter and receiver chain gains in dB, respectively, G_TA and G_RA are the total transmitting and receiving antenna gains in dB, respectively, and PL is the channel path loss in dB. Keep in mind that EM.Terrano is fully polarimetric. The transmitting and receiving antenna characteristics are specified through the imported radiation pattern files, which are part of the definition of the transmitters and receivers. In particular, the polarization mismatch losses are taken into account through the polarimetric SBR ray tracing analysis.

If you specify the noise-related parameters of your receiver set, the signal-to-noise ratios (SNR) is calculated at each receiver location: SNR == P_r - P_n, where P_n is the noise power level in dB. When planning, designing and deploying a communication system between points A and B, the link is considered to be closes and a connection established if the received signal power at the location of the receiver is above the noise power level by a certain threshold. In other words, the SNR at the receiver must be greater than a certain specified minimum SNR level. You specify (SNR)_min ss part of the definition of receiver chain in the Receiver Set dialog. In the "Visualization Options" section of this dialog, you can also check the check box labeled '''Generate Connectivity Map'''. This is a binary-level black-and-white map that displays connected receivers in white and disconnected receivers in black. At the end of an SBR Simulation Parameters ==simulation, the computed SNR is displayed in the Receiver Set dialog for the selected receiver. The connectivity map is generated and added to the navigation tree underneath the received power coverage map node.

There are a number of SBR simulation settings that can be accessed and changed from At the end of an SBR Settings Dialog. To open this dialogsimulation, click you can visualize the button labeled '''Settings''' on the right side field maps and receiver power coverage map of your receiver sets. A coverage map shows the total '''Select EngineReceived Power''' dropdown list in by each of the Run Dialogreceivers and is visualized as a color-coded intensity plot. EM.Cube's SBR simulation engine allows you to separate Under each receiver set node in the physical effects that are calculated during navigation tree, a ray tracing processtotal of seven field maps together with a received power coverage map are added. You can selectively enable or disable '''Ray Reflection''', '''Ray Transmission'''The field maps include amplitude and '''Ray Diffraction'''phase plots for the three X, Y, Z field components plus a total electric field plot. By defaultTo display a field or coverage map, all three effects are checked and included simply click on its entry in the computationsnavigation tree. Separating these effects sometimes help you better analyze The 3D plot appears in the Main Window overlaid on your propagation scene . A legend box on the right shows the color scale and understand units (dB). The 3D coverage maps are displayed as horizontal confetti above the impact receivers. You can change the appearance of various blocks in the scenereceivers and maps from the property dialog of the receiver set. You can further customize the settings of the 3D field and coverage plots.

EM<table><tr><td>[[Image:AnnArbor Scene1.Cube requires a finite number png|thumb|left|640px|The downtown Ann Arbor propagation scene.]]</td></tr><tr><td>[[Image:AnnArbor Scene2.png|thumb|left|640px|The electric field distribution map of ray bounces for each original ray emanating from a the Ann Arbor scene with vertical dipole transmitterand receivers. This is very important in situations that may involve resonance effects where rays get trapped among certain group ]]</td></tr><tr><td>[[Image:AnnArbor Scene3.png|thumb|left|640px|The received power coverage map of surfaces and may bounce back the Ann Arbor scene with vertical dipole transmitter and forth indefinitelyreceivers. This is set using the box labeled &quot;'''Max No]]</td></tr><tr><td>[[Image:AnnArbor Scene4. Ray Bounces'''&quot;, which has a default value png|thumb|left| 640px |The connectivity map of 10. Note that the maximum number of ray bounces directly affects Ann Arbor scene with SNR_min = 3dB with the computation time as well as the size of output simulation data filesbasic color map option. This can become critical for indoor propagation scenes, where most ]]</td></tr><tr><td>[[Image:AnnArbor Scene5.png|thumb|left| 640px |The connectivity map of the rays undergo a large number of reflectionsAnn Arbor scene with SNR_min = 20dB with the basic color map option.   ]]</td></tr></table>

 As rays travel in === Visualizing the scene and bounce from surfaces, they lose their power and their amplitudes diminish. From a practical point of view, only rays that have power above the receiver ensitivity threshold can be effectively received. Therefore, all the rays whose power fall below a specified power threshold are discarded. The '''Ray Power Threshold'''is specified Rays in dBm and has a default value of -100dBm. Keep in mind that the value of this threshold directly affects the accuracy of the simulation results as well as the size of the output data file.Scene ===

You can also set the '''Angular Resolution''' of the transmitter rays in degrees. By default, every transmitter emanates equi-angular ray tubes at a resolution of 1 degree. Lower angular resolutions larger than 1° speed up the SBR simulation significantly, but they may compromise the accuracy. Higher angular resolutions less than 1° increase the accuracy of the simulatin results, but they also increase the computation time. [[File:PROP13.png]] Figure 1: Propagation Module's SBR Engine Settings dialog. == The Coverage Map == If the associated radiator set is isotropic, so will be the transmitter set. By default, an isotropic transmitter has vertical polarization. You can use the '''Polarization''' radio button to select one of the two options: '''Vertical''' or '''Horizontal'''. If the associated radiator set consists of '''Short Dipole''' or '''User Defined''' radiators, it is indicated in the transmitter property dialog. In the case of a short dipole radiator, you can set a value for the dipole current in Amperes. The radiation resistance of a short dipole of length ''dl'' is given by: [[File:manuals/emagware/emcube/modules/propagation/sources-observables/directional-transmitters-receivers/eqngr6.png]] The radiated power of a short dipole carrying a current I₀ is then given by: [[File:manuals/emagware/emcube/modules/propagation/sources-observables/directional-transmitters-receivers/shortdipole.png]] For isotropic and user defined radiators you can set the '''Input Power''' and '''Phase''' of a transmitter set in Watts and degrees, respectively. This can be accessed from the '''Transmitter Chain''' dialog, which will be described in detail in the next section. The radiation pattern of the associated radiator set is normalized and used in conjunction with the input power value to create a weighted distribution of transmitted rays. In certain cases like hybrid simulations, you may want to use the actual values of the far field to define the transmitter power rather than a normalized radiation pattern. Note that the pattern (.RAD) file contains the value of total radiated power in its header. In this case, check the box labeled '''&quot;Calculate Power From Radiation Pattern&quot;'''. This is calculated directly from the complex &theta; and &phi; components of the far field data by integrating them over the entire space (4&pi; solid angle). Note that this option is available only when the radiator is of the User Defined type. When this box is checked, the transmitter chain button is grayed out. By default, an isotropic transmitter emanates rays uniformly in all directions at the angular resolution specified by the user. A transmitter with a user defined associated radiator may represent a highly directional radiation pattern with the main beam pointing in a certain direction. You can additionally force and limit the '''Angular Extents''' of rays to a certain solid angle around the transmitter. This is especially useful and computationally efficient when the transmitter is on one side of the scene, and all the scatterers and receivers are on the other side. In this case, there is no need to generate rays in all directions. To limit the angular extents of rays, define the Start and End values for both Theta (&theta;) and Phi (&phi;) angles. The value of the angular resolution of the rays can be changed from the Run Dialog as will be discussed later. In a regular SBR simulation, you have a transmitter and one or more arrays of receivers in your scene. At the end of the simulation, you can visualize the coverage map of the transmitter over the receiver sets. A coverage map shows the total '''Received Power''' by each of the receivers and is visualized as a color-coded intensity plot. You can visualize the coverage maps of individual receiver sets. At the end of a SBR simulation, each Received Power Coverage Map is listed under the receiver set's name in the Navigation Tree. To display a coverage map, simply click on its entry in the Navigation Tree. The coverage map plot appears in the Main Window overlaid on the scene. A legend box on the right shows the color scale and units (dB). The 3-D coverage maps are displayed as horizontal confetti above the receivers. If the receivers are packed close to each other, you will see a continuous confetti map. If the receivers are far apart, you will see individual colored squares. You can also visualize coverage maps as colored 3-D cubes. This may be useful when you set up your receivers in a vertical arrangement or the scene has a highly uneven terrain. To change the type of coverage mapvisualization, open the receiver set's property dialog and select the desired option for '''Coverage Map: Confetti''' or '''Cube''' in the '''&quot;Visualization Options&quot;''' section of the dialog. [[File:manuals/emagware/emcube/modules/propagation/running-a-sbr-simulation/received-power-coverage-map/prop_run11_tn.png]]    [[File:manuals/emagware/emcube/modules/propagation/running-a-sbr-simulation/received-power-coverage-map/prop_run12_tn.png]] Received power converage map: (Left) confetti style, and (Right) cube style. You can change the settings of the coverage map by right clicking on its entry in the Navigation Tree and selecting '''Properties...''' or by double-clicking on the legend box. In the Output Plot Settings dialog, you can choose from one of three Color Map options: '''Default''', '''Rainbow''' and '''Grayscale'''. The visualization plot uses default values for the color scale. In the section titled &quot;Limits&quot;, you can choose the radio button labeled '''User Defined'''. Then, you have to enter new values for the '''Lower''' and '''Upper''' Limits of the plot. You can also show or hide the Legend Box or change its '''Background''' and '''Foreground''' colors by clicking the buttons provided for this purpose. [[File:manuals/emagware/emcube/modules/propagation/running-a-sbr-simulation/received-power-coverage-map/prop_run4.png]] Output Plot Settings == The Ray Data == At the end of a SBR simulation, each receiver receives a number of rays. Some receivers may not receive any rays at all. You can visualize all the rays received by a certain receiver from the active transmitter of the scene. To do this, right click the '''Receivers''' item of the Navigation Tree. From the context menu select '''Show Received Rays'''. All the rays received by the currently selected receiver of the scene are displayed in the scene. The rays are identified by labels,are ordered by their power and have different colors for better visualization. You can display the rays for only one receiver at a time. The receiver set property dialog has a list of all the individual receivers belonging to that set. To display the rays received by another receiver, you have to change the '''Selected Receiver''' in the receiver set's property dialog. If you keep the mouse focus on this dropdown list and roll your mouse scroll wheel, you can scan the selected receivers and move the rays from one receiver to the next in the list. To remove the visualized rays from the scene, right click the Receivers item of the Navigation Tree again and from the context menu select '''Hide Received Rays'''. [[File:manuals/emagware/emcube/modules/propagation/running-a-sbr-simulation/the-ray-data/prop_run5_tn.png]][[files/images/manuals/emagware/emcube/modules/propagation/running-a-sbr-simulation/the-ray-data/prop_run5.png|files/images/manuals/emagware/emcube/modules/propagation/running-a-sbr-simulation/the-ray-data/prop_run5.png]] Visualization of received rays at the location of the selected receiver.

The Ray Data Dialog also shows the '''Total Received Power''' in dBm and '''Total Received Field''' in dBV/m due to all the rays received by the receiver<table><tr><td> [[Image:UrbanCanyon17.You can sort the rays based on their delay, field, power, etcpng|thumb|left|720px|EM. To do so, simply click on the grey column label in the table to sort the rays in ascending order based on the Terrano's ray data dialog showing a selected parameterray.You can also select any ray by clicking on its '''ID''' and highlighting its row in the ]] </td></tr></table. In that case, the selected rays is highlighted in the Project Workspace and all the other rays become thin (faded).>

Note: The Ray Data Dialog also shows the '''Total Received Power''' in dBm and '''Total Received Field''' in dBV/m due to all the rays are summed up coherently at received by the receiver. You can sort the rays based on their delay, field, power, etc. To do so, simply click on the grey column label in the table to sort the rays in ascending order based on the selected parameter. You can also select any ray by clicking on its '''ID''' and highlighting its row in the table. In that case, the selected rays is highlighted in the Project Workspace and all the other rays become thin (faded).

[[File:manuals/emagware/emcube/modules/propagation/running-a-sbr-simulation/{{Note|All the-ray-data/prop_run6_tn.png]][[files/images/manuals/emagware/emcube/modules/propagation/running-a-sbr-simulation/the-ray-data/prop_run6.png|files/images/manuals/emagware/emcube/modules/propagation/running-received rays are summed up coherently in a-sbr-simulation/vectorial manner at the-ray-data/prop_run6receiver location.png]]}}

Analyzing <table><tr><td> [[Image:UrbanCanyon18.png|thumb|left|640px|Visualization of received rays at the location of a selected ray from receiver in the ray data dialograndom city scene.]] </td></tr>== Plotting Other Simulation Results ==</table>

Besides visualizing the coverage map and received rays in the EM.CUBE's Propagation Module, you can also plot the '''Path Loss''' of all the receivers belonging to a receiver set as well as the '''Power Delay Profile''' of individual receivers. To plot these data, go the '''Observables''' section of the Navigation Tree and right click on the '''Receivers''' item. From the context menu, select '''Plot Path Loss''' or '''Plot Power Dlay Profile''', respectively. === The path loss data between the active transmitter and all the receivers belonging to a receiver set are plotted on a Cartesian graph. The horizontal axis of this graph represents the index of the receiver. Power Delay Profile is a bar chart that plots the power of individual rays received by the currently selected receiver versus their time delay. If there is a line of sight (LOS) between a transmitter and receiver, the LOS ray will have the smallest delay and therefore will appear first in the bar chart. Sometimes you may have several rays arriving at a receiver at the same time, i.e. all with the same delay, but with different power level. These will appear as stacked bars in the chart. You can also plot the path loss and power delay profile graphs and many others from EM.CUBE's data manager. You can open data manager by clicking the '''Standard Output Data Manager''' [[File:manuals/emagware/emcube/modules/propagation/running-a-sbr-simulation/plotting-other-simulation-results/data_manager_icon.png]] button of the '''Compute Toolbar''' or by selecting '''Compute [[File:manuals/emagware/emcube/modules/propagation/hybrid-simluations/illuminating-periodic-walls-using-sbr/larrow_tn.png]]Data Manager''' from the menu bar or by right clicking on the '''Data Manager''' item of the Navigation Tree and selecting Open Data Manager... from the contextual menuor by using the keyboard shortcut '''Ctrl+D'''. In the Data manager Dialog, you will see a list of all the data files available for plotting. These include the theta and phi angles of arrival and departure of the selected receiver. You can select any data file by clicking and highlighting its '''ID''' in the table and then clicking the '''Plot''' button. == Output Data Files ==

NEW LINEEach receiver line has the following information:

* Receiver NumberID* Receiver Base X, Y , Z Coordinatescoordinates* Receiver HeightTotal received power in dBm* Total number of received rays

NEW LINEEach rays line received by a receiver has the following information:

Number of Rays NEW LINE:* Ray Index* Ray NumberDelay in nsec

* Delay in nsec* Real(and imaginary parts of the three E<supsub>Vx</supsub>) &amp; Imag(, E^V)* Real(E^H) &amp; Imag(E^H)* Real('''E.e_Ry''') &amp; Imag(''', E.e_Rz''')components* Number of ray hit points * PowerCoordinates of individual hit points

The angles of arrival are the &theta; and &phi; angles of a received ray measured in degrees and are referenced in the local spherical coordinate systems centered at the location of the receiver. The angles of departure for a received ray are the &theta; and &phi; angles of the originating transmitter ray, measured in degrees and referenced in the local spherical coordinate systems centered at the location of the active transmitter, which eventually arrives at the receiver. The total time delay is measured in nanoseconds between t = 0 nsec at the time of launch from the transmitter location till being received at the receiver location. The last four columns show the real and imaginary parts of the received electric fields with vertical and horizontal polarizations, respectively.The complex field values are normalized in a way that when their magnitude is squared, it equals the received ray power. If the active transmitter is an isotropic radiator with either a vertical or horizontal polarization, then the field components corresponding to the other polarization will have zero entries in the output data file.

<table><tr><td> [[FileImage:manuals/emagware/emcube/modules/propagation/visualizing-sbr-simulation-data/prop_run8_tn.png|thumb|left|720px|A typical SBR output-data-files/prop_run8_tnfile.png]]</td></tr></table>

By default, you run a single-frequency simulation The available data files in EM.CUBE's Propagation Module. You set the operational frequency "2D Data Files" tab of a SBR simulation in the project's '''Frequency Dialog''', which can be accessed in a number of waysData Manger include:

# By clicking the * '''FrequencyPath Loss''' [[File:manualsThe channel path loss is defined as PL = P<sub>r</emagware/emcube/modules/propagation/runningsub> -EIRP. The path loss data are stored in a-sbr-simulation/running-file called "SBR_receiver_set_name_PATHLOSS.DAT" as a-frequency-sweep-with-sbr/freq_icon.png]] button function of the '''Compute Toolbar'''receiver index. The path loss data make sense only if your receiver set has the default isotropic radiator.# By selecting * '''ComputePower Delay Profile''' [[File:manuals/emagware/emcube/modules/propagation/running-a-sbr-simulation/running-a-parametric-sweep-The delays of the individual rays received by the selected receiver with-sbr/larrow_tnrespect to the transmitter are expressed in ns and tabulated together with the power of each ray in the file "SBR_receiver_set_name_DELAY.png]]'''Frequency SettingsDAT"...''' You can plot these data from the Menu BarData Manager as a bar chart called the power delay profile.# Using The bars indeed correspond to the keyboard shortcut difference between the ray power in dBm and the minimum power threshold level in dBm, which makes them a positive quantity. * '''Ctrl+FAngles of Arrival'''.# By double clicking : These are the frequency section (box) Theta and Phi angles of the '''Status Bar'''individual rays received by the selected receiver and saved to the files "SBR_receiver_set_name_ThetaARRIVAL.<br />  ANG" and "SBR_receiver_set_name_PhiARRIVAL.ANG". You can plot them in the Data Manager in polar stem charts.

[[File:manuals/emagware/emcube/modules/propagation/running-When you run a-sbr-simulation/running-a-frequency-or parametric sweep-with-sbr/prop_freqin [[EM.pngTerrano]]    , a tremendous amount of data may be generated. [[File:manuals/emagware/emcube/modules/propagation/running-a-sbr-simulation/running-a-frequency-sweep-with-sbr/prop_run10EM.pngTerrano]]only stores the '''Received Power''', '''Path Loss''' and '''SNR''' of the selected receiverin ASCII data files called "PREC_i.DAT", "PL_i.DAT" and "SNR_i.DAT", where is the index of the receiver set in your scene. These quantities are tabulated vs. the sweep variable's samples. You can plot these files in EM.Grid.

(Left) Project[[Image:Info_icon.png|40px]] Click here to learn more about working with data filed and plotting graphs in [[EM.Cube]]'s frequency dialog and (Right) the frequency settings dialog'''[[Defining_Project_Observables_%26_Visualizing_Output_Data#The_Data_Manager | Data Manager]]'''.

You can also select the '''Frequency Sweep''' option in the '''Simulation Mode''' drop-down list of the '''Run Dialog'''<table><tr><td> [[Image:Terrano pathloss. Click the '''Settings...''' button on the right side png|thumb|360px|Cartesian graph of this dropdown list to open up the Frequency Settings Dialogpath loss. Based on the original values of the project center frequency and bandwidth, the '''Start Frequency''' and '''End Frequency''' have default values]] </td><td> [[Image:Terrano delay. You can also change the '''Number png|thumb|360px|Bar graph of Samples'''power delay profile. Once you click the '''Run''' button, EM]] </td></tr><tr><td> [[Image:Terrano ARR phi.CUBE performs a frequency sweep by assigning each png|thumb|360px|Polar stem graph of Phi angle of the frequency samples as the current operational frequency and running the SBR simulation engine at that frequencyarrival. All the simulation data at all frequency samples are saved into the output data files including &quot;SBR_results.RTOUT&quot;]] </td><td> [[Image:Terrano ARR theta. After the completion png|thumb|360px|Polar stem graph of a frequency sweep simulation, as many coverage maps as the number Theta angle of frequency samples are generated and added to the Navigation Tree under the Receiver Set's entryarrival. You can click on each ]] </td></tr><tr><td> [[Image:Terrano DEP phi.png|thumb|360px|Polar stem graph of the coverage maps corresponding to each Phi angle of the frequency samples and visualize it in the project workspacedeparture.You can also animate the coverage maps]] </td><td> [[Image:Terrano DEP theta. To do so, right click on the receiver set's name in the Navigation Tree and select '''Animation''' from the contextual menu. The coverage mapsstart to animate by their order on the Navigation Tree. Once the entire list is displayed sequentially, it starts all over again from the beginning png|thumb|360px|Polar stem graph of the list.During the animation, the '''Animation Controls''' dialog appears at the lower right corner Theta angle of the screendeparture. This dialog has a number of buttons for pause]] </resume, step forwardtd></backward, andstep to the endtr></start. The title of each coverage map is shown in the box labeled '''Sample''' as it is displayed in the main window. You can also change the speed of animation. The default frame duration has a value of 300 (3x100) milliseconds. To stop the animation, simply press the keyboard's '''Esc Key'''.table>

Multiple coverage maps on When you designate a "User Defined Antenna Pattern" as the Navigation Tree radiator type of a transmitter set or a receiver set, EM.Terrano copies the imported radiation pattern data file from its original folder to the current project folder. The name of the ".RAD" file is listed under the '''3D Data Files''' tab of the data manager. Sometimes it might be desired to visualize these radiation patterns in your propagation scene at the end actual location of the transmitter or receiver. To do so, you have to define a frequency sweep new '''Radiation Pattern''' observable in the navigation tree. The label of the new observable must be identical to the name of the ".RAD" data file. In addition, the Theta and starting an animation from Phi angle increments of the new radiation pattern observable (expressed in degrees) must be identical to the Theta and Phi angular resolutions of the imported pattern file. If all these conditions are met, then go to the '''Simulate Menu''' and select the item '''Update All 3D Visualization'''. The contents of the 3D radiation patterns are added to the navigation tree. Click on one of the radiation pattern items in the navigation tree and it will be displayed in the contextual menuscene.

<table><tr><td>[[FileImage:manuals/emagware/emcube/modules/propagation/running-UrbanCanyon6.png|thumb|left|640px|The received power coverage map of the random city scene with a-sbr-simulation/running-a-frequency-sweep-with-sbr/prop_run15_tnhighly directional dipole array transmitter.png]]</td></tr></table>

Animation controls By Default, [[EM.Cube]] always visualizes the 3D radiation patterns at the origin of coordinates, i.e. at (0, 0, 0). This is because that radiation pattern data are computed in the standard spherical coordinate system centered at (0, 0, 0). The theta and phi components of the far-zone electric fields are defined with respect to the X, Y and Z axes of this system. When visualizing the 3D radiation pattern data in a propagation scene, it is more intuitive to display the pattern at the location of the transmitter or receiver. The Radiation Pattern dialog allows you to translate the pattern visualization to any arbitrary point in the project workspace. It also allows you to scale up or scale down the pattern visualization with respect to the background scene.

== Running In the example shown above, the imported pattern data file is called "Dipole_Array1.RAD". Therefore, the label of the radiation pattern observable is chosen to be "Dipole_Array1". The theta and phi angle increments are both 1&deg; in this case. The radiation pattern has been elevated by 10m to be positioned at the location of the transmitter and a Parametric Sweep with SBR ==scaling factor of 0.3 has been used.

In EM<table><tr><td>[[Image:UrbanCanyon8.CUBE, all png|thumb|left|640px|Setting the CAD object properties as well as certain source, material and mesh pattern parameters can be assigned as variablesin the radiation pattern dialog. Variables are defined to control and vary ]]</td></tr></table><table><tr><td>[[Image:UrbanCanyon7.png|thumb|left|720px|Visualization of the values 3D radiation pattern of such parameters either for editing purposes or to run parametric sweep or optimization.Veriable are defined using the '''Variables Dialog''', which can be accessed directional transmitter in the three ways:random city scene.]]</td></tr></table>

# By clicking the '''Variables''' [[File:manuals/emagware/emcube/modules/propagation/running-There is an important catch to remember here. When you define a-sbr-simulation/running-a-parametric-sweep-with-sbr/variable_iconradiation pattern observable for your project, EM.png]] button Terrano will attempt to compute the overall effective radiation pattern of the '''Compute Toolbar'''entire physical structure.# By selecting '''Compute''' [[File:manuals/emagware/emcube/modules/propagation/running-a-sbr-simulation/running-a-parametric-sweep-with-sbr/larrow_tnHowever, in this case, you defined the radiation pattern observable merely for visualization purposes.png]][[files/images/manuals/emagware/emcube/modules/propagation/running-a-sbr-simulation/running-a-parametric-sweep-with-sbr/larrowTo stop EM.png|files/images/manuals/emagware/emcube/modules/propagation/running-Terrano from computing the actual radiation pattern of your entire scene, there is a-sbr-simulation/running-a-parametric-sweep-with-sbr/larrowcheck box in EM.png]] Terrano's Ray Tracer Simulation Engine Settings dialog that is labeled ''Variables...'Do not compute new radiation patterns'' from '. This box is checked by default, which means the Menu Baractual radiation pattern of your entire scene will not be computed automatically.# Using the keyboard shortcut '''Ctrl+B''But you need to remember to uncheck this box if you ever need to compute a new radiation pattern using EM.Terrano's SBR solver as an asymptotic EM solver (see next section).

The variables dialog is initially empty<table><tr><td>[[Image:UrbanCanyon9. To add a new variable, click the '''Add''' button to open up the '''Add Variable/Syntax Dialog'''png|thumb|left|640px|EM.In this dialog you have to type in a name for the new variable and choose a type. The default type is Terrano'''Uniformly Spaced Samples'''. You also need to specify the '''Start''', '''Stop''' and '''Step''' values for the variable. In the figure below, a variable called &quot;Tx_Height&quot; is defined that varies between 2 and 10 with equal steps of 2. This means the sample set {2,4,6,8,10}. When you return to the variables s Run Simulation dialog, the syntax of the new variable is shown as 2:10:2. The last number in this syntax is always the variable step. In this example, this variable is going to be used to control the height of the transmitterin a propagation scene.]]</td></tr></table>

[[File:manuals/emagware/emcube/modules/propagation/running-a-sbr-simulation/running-a-parametric-sweep-with-sbr/prop_run24== Using EM.png]]    [[File:manuals/emagware/emcube/modules/propagation/running-a-sbr-simulation/running-a-parametric-sweep-with-sbr/prop_run23.png]]Terrano as an Asymptotic Field Solver ==

Like every other electromagnetic solver, EM.CUBETerrano's variable dialog SBR ray tracer requires an excitation source and one or more observables for the dialog generation of simulation data. EM.Terrano offers several types of sources and observables for defining a new variableSBR simulation. You already learned about the transmitter set as a source and the receiver set as an observable. You can mix and match different source types and observable types depending on the requirements of your modeling problem.

Next, you have to attach the variable to the CAD object. In this case, the CAD object is the point object that represents the transmitter's radiator.To attach a variable to a CAD object, open the object's property dialog and type The available source types in the name of the variable as the value of a property or parameterEM. In this case, the variable Tx_Height is going to control the Z-Coordinate of the point object. Once the value of the object parameter is replaced by the name of an already defined variable,it is updated with the current value of that variable. In the case of a variable of &quot;Uniformly Spaced Samples&quot; type, the current value is the start value. This value will be incrementally varied during a parametric sweep simulation process. Note that a variable can take a fixed value or a discrete set of values, too. You can always open the variables dialog and change the value or syntax of any variable. To make a new or modified value effective, click the '''Apply''' button of the variables dialog. You cantest the values by performing a '''Dry Run''' of the selected variable. This runs an animation of the project workspace as the value of the variable changes and all the relatedCAD objects Terrano are updated accordingly. Note that you can attach the same variable to more than one CAD object property or to the properties of different objects. You can also define multiple values or syntaxes to the same variable. To do so, open the '''Add Variable/Syntax Dialog''', and instead of typing in a new variable name, choose an existingvariable name from the '''Name''' dropdown list. This will add a new value or syntax to the existing syntax(es) of the selected variable. When you return to the variables dialog, variables with more than one value or syntax will have a dropdown list in the '''Syntax''' column. You can choose any of these values or syntaxed at any time and make the change effective by clicking the '''Apply''' button.:

{| class="wikitable"|-! scope="col"| Icon! scope="col"| Source Type! scope="col"| Applications! scope="col"| Restrictions|-| style="width:30px;" | [[File:manuals/emagware/emcube/modules/propagation/running-transmitter_icon.png]]| style="width:150px;" | [[Glossary of EM.Cube's Materials, Sources, Devices & Other Physical Object Types#Point Transmitter Set | Point Transmitter Set]]| style="width:250px;" | Modeling realsitic antennas & link budget calculations| style="width:250px;" | Requires to be associated with abase location point set|-sbr| style="width:30px;" | [[File:hertz_src_icon.png]]| style="width:150px;" | [[Glossary of EM.Cube's Materials, Sources, Devices & Other Physical Object Types#Hertzian Short Dipole Source | Hertzian Short Dipole]]| style="width:250px;" | Almost omni-simulation/runningdirectional physical radiator| style="width:250px;" | None, stand-a-parametricalone source|-sweep-with-sbr/prop_run25| style="width:30px;" | [[File:huyg_src_icon.png]]| style="width:150px;" | [[Glossary of EM.Cube's Materials, Sources, Devices & Other Physical Object Types#Huygens Source | Huygens Source]]| style="width:250px;" | Used for modeling equivalent sources imported from other [[EM.Cube]] modules | style="width:250px;" | None, stand-alone source imported from a Huygens surface data file|}

Replacing Click on each type to learn more about it in the value [[Glossary of a CAD object parameter with a variable nameEM.Cube's Materials, Sources, Devices & Other Physical Object Types]].

To run a parametric sweep, open the '''Run Dialog''' and select the '''Parametric Sweep''' option The available observables types in the '''Simulation Mode''' drop-down list.If you have not defined any variables in the project, the box in the '''Variables''' row before the '''View''' will be red. You have to turn it into green before you can run a simulation.By clicking the '''View''' button, you can open up the variables dialog from here. Once you click the '''Run''' button, [[EM.CUBE performs a parametric sweep by incrementally varying the values of all the defined variables from their start to stop values at the specified steps and updatingall the related CAD objects. After the completion of a parametric sweep simulation, as many coverage maps as the total number of variable samples Terrano]] are generated and added to the Navigation Tree under the receiver set's entry. You can click on each of the coverage maps and visualize it in the project workspace.You can also animate the coverage maps sequentially. To do so, right click on the receiver set's name in the Navigation Tree and select '''Animation''' from the contextual menu. To stop the animation, simply press the keyboard's '''Esc Key'''.:

{| class="wikitable"|-! scope="col"| Icon! scope="col"| Source Type! scope="col"| Applications! scope="col"| Restrictions|-| style="width:30px;" | [[File:manuals/emagware/emcube/modules/propagation/runningreceiver_icon.png]]| style="width:150px;" | [[Glossary of EM.Cube's Simulation Observables & Graph Types#Point Receiver Set | Point Receiver Set]]| style="width:250px;" | Generating received power coverage maps & link budget calculations| style="width:250px;" | Requires to be associated with a base location point set|-| style="width:30px;" | [[File:Distr Rx icon.png]]| style="width:150px;" | [[Glossary of EM.Cube's Simulation Observables & Graph Types#Distributed Receiver Set | Distributed Receiver Set]]| style="width:250px;" | Computing received power at areceiver characterized by Huygens surface data| style="width:250px;" | None, stand-sbralone source imported from a Huygens surface data file|-simulation/running| style="width:30px;" | [[File:fieldsensor_icon.png]]| style="width:150px;" | [[Glossary of EM.Cube's Simulation Observables & Graph Types#Near-aField Sensor Observable | Near-parametricField Sensor]]| style="width:250px;" | Generating electric and magnetic field distribution maps| style="width:250px;" | None, stand-sweepalone observable|-with| style="width:30px;" | [[File:farfield_icon.png]]| style="width:150px;" | [[Glossary of EM.Cube's Simulation Observables & Graph Types#Far-sbr/prop_run26Field Radiation Pattern Observable | Far-Field Radiation Pattern]]| style="width:250px;" | Computing the effective radiation pattern of a radiator in the presence of a large scattering scene | style="width:250px;" | None, stand-alone observable|-| style="width:30px;" | [[File:huyg_surf_icon.png]]| style="width:150px;" | [[Glossary of EM.Cube's Simulation Observables & Graph Types#Huygens Surface Observable | Huygens Surface]]| style="width:250px;" | Collecting tangential field data on a box to be used later as a Huygens source in other [[EM.Cube]] modules| style="width:250px;" | None, stand-alone observable|}

Choosing parametric sweep as the simulation mode Click on each type to learn more about it in the run dialog[[Glossary of EM. Note Cube's Simulation Observables & Graph Types]]. When you define a far-field observable in EM.Terrano, a collection of invisible, isotropic receivers are placed on the surface of a large sphere that one variable has been defined encircles your propagation scene and EMall of its geometric objects.CUBE These receivers are placed uniformly on the spherical surface at a spacing that is ready determined by your specified angular resolutions. In most cases, you need to run define angular resolutions of at least 1&deg; or smaller. Note that this is different than the simulationtransmitter rays' angular resolution. You may have a large number of transmitted rays but not enough receivers to compute the effective radiation pattern at all azimuth and elevation angles. Also keep in mind that with 1&deg; Theta and Phi angle increments, you will have a total of 181 &times; 361 = 65,341 spherically placed receivers in your scene.

{{Note| Computing radiation patterns using EM.Terrano's SBR solver typically takes much longer computation times than using [[File:manuals/emagware/emcube/modules/propagation/running-a-sbr-simulation/running-a-parametric-sweep-with-sbr/prop_run27_tnEM.pngCube]]'s other computational modules.}} <table><tr><td> [[files/images/manuals/emagware/emcube/modules/propagation/running-a-sbr-simulation/running-a-parametric-sweep-with-sbr/prop_run27Image:SBR pattern.png|files/images/manuals/emagware/emcube/modules/propagation/running-a-sbr-simulation/running-a-parametric-sweep-with-sbr/prop_run27thumb|540px|Computed 3D radiation pattern of two vertical short dipole radiators placed 1m apart in the free space at 1GHz.png]]</td></tr>The coverage map of the scene at the end of a parametric sweep where the sweep variable is the transmitter height.</table>

EM.CUBETerrano's coverage maps display the received power at the location of all the receivers. The receivers together from a set/ensemableensemble, which might be uniformly spaced or distributed across the propagation scene or may consist of randomly scattered radiators. Every coverage map shows the '''Mean''' and '''Standard Deviation''' of the received power for all the receivers involved. These information are displayed at the bottom of the coverage map's legend box and are expressed in dB. When you run either a frequency sweep or a parametric sweep simulation in EM.Terrano, you have the option to generate two additional coverage maps: one for the mean of all the individual sample coverage maps and another for their standard deviation. To do so, in the '''Run Dialog''', check the box labeled '''&quot;Create Mean and Standard Deviation received power coverage maps&quot;'''. Note that the mean and standard deviation values displayed on the individual coverage maps correspond to the spatial statistics of the receivers in the scene, while the mean and standard deviation coverage maps show the statistics with respect to the frequency or other sweep variable sets at each point in the site. Also, note that both of the mean and standard deviation coverage maps have their own spatial mean and standard deviation values expressed in dB at the bottom of their legend box. <table><tr><td> [[Image:PROP MAN12.png|thumb|left|480px|EM.Terrano's simulation run dialog showing frequency sweep as the simulation mode along with statistical analysis.]] </td></tr></table> <table><tr><td> [[Image:UrbanCanyon4.png|thumb|left|640px|The mean coverage map at the end of a frequency sweep.]] </td></tr><tr><td> [[Image:UrbanCanyon5.png|thumb|left|640px|The standard deviation coverage map at the end of a frequency sweep.]] </td></tr></table>

The mean coverage map at [[Image:Top_icon.png|30px]] '''[[EM.Terrano#Product_Overview | Back to the end Top of a transmitter sweep.the Page]]'''

[[FileImage:manuals/emagware/emcube/modules/propagation/running-a-sbr-simulation/statistical-analysis-of-propagation-scene/prop_run22_tnTutorial_icon.png|30px]]'''[[EM.Cube#EM.Terrano_Documentation | EM.Terrano Tutorial Gateway]]'''

The standard deviation coverage map at the end of a transmitter sweep[[Image:Back_icon.png|30px]] '''[[EM.Cube | Back to EM.Cube Main Page]]'''