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{{projectinfo|Application|Simulating The Performance Of Installed Antennas On Vehicular Platforms Using EM.Tempo|ART_GOLF_Fig_title.png|In this project, large parabolic reflectors fed by pyramidal horn antennas mounted on a complex, real-sized, automobile platform are modeled and analyzed using EM.Illumina and EM.Tempo.|*[[Building Geometrical Constructions in CubeCAD | CubeCAD]]

*[[EM.Illumina]]CAD Model*Pyramidal HornPatch Wizard*Parabola*Object of RevolutionYee Mesh

| 3.8×10⁶) S/m| Wheel rims

== Simulating the Patch Antenna on the Vehicle 's Roof ==

[[Image:Roof patch.png|thumb|left|480px420px| The location of the patch antenna on the vehicle 's roof.]]

By default, [[EM.Tempo]]'s mesh generator tries to place grid points at the corners of each graphic object's bounding box, and also at any internal boundaries any object may have. For models with a large number of complex geometric objects, this could drive the typical mesh cell size toward the "Absolute Minimum Grid Spacing", and would result in a much denser mesh than is required. Since the Golf model has more than 2000 distinct graphic objects, we will turn off some of these adaptive mesh options. A mesh density of 18 cells per effective wavelength is chosen for this structure with the absolute minimum grid spacing parameter set equal to 0.75mm. The figures below show the Yee mesh of the overall whole vehicle structure as well as the portion of the roof in the proximity of the installed patch antenna. The overall mesh involves <b><u>220 million</u></b> cells.

[[Image:Roof patch mesh.png|thumb|left|480px640px| The location mesh of the patch antenna on the vehicle roofstructure generated by EM.Tempo.]]

[[Image:Roof patch mesh.png|thumb|left|480px420px| The location A close-up of the mesh of the patch antenna on and its neighboring region of the vehicle 's roof.]]

The Mirage III CAD model has an approximate length of 15m, a wingspan of 8m, and an approximate height of 4.5m. Expressed in freefigure below shows the 3D far-space wavelengths at 850 MHz, the approximate dimensions field radiation pattern of the aircraft model are 42.5 &#955;₀ x 22.66 &#955;₀ x 12.75 &#955;₀. Thus, for installed patch antenna on the purposes of [[EM.Tempo]], we need to solve a region of about 12,279 cubic wavelengthsvehicle's roof. For problems of this sizesimulation, a very large CPU memory is needed, and a highthe far-performance, multi-core CPU is desirable field angular resolution was set to reduce the simulation time2.5&deg; along both azimuth and elevation directions.

<table><tr><td>[https[Image://awsRoof pattern.amazon.com/ Amazon Web Services] allows one to acquire highpng|thumb|left|640px| 3D far-performance compute instances on demand, and pay on a perfield radiation pattern of the vehicle-use basis. To be able to log into an Amazon instance via Remote Desktop Protocol (RDP)antenna combination structure, with the [[EMpatch antenna installed on the vehicle's roof.Cube]] license must allow terminal services. For the purpose of this project, we used a c4.4xlarge instance running Windows Server 2012. This instance has 30 GB of RAM memory, and 16 virtual CPU cores. The CPU for this instance is an Intel Xeon E5-2666 v3 (Haswell) processor.</td></tr></table>

Farfield Resolution<table><tr><td>[[Image: 2Hood mount.5 degreespng|thumb|left|480px| The location of the patch antenna on the vehicle's hood.]]</td></tr></table>

Simulation Time: 4 hoursThe figure below shows the details of the Yee mesh around the new location of the patch antenna. Due to the curvature of the surface of most parts in this area, 45 minutesthe generated mesh has denser grid lines. This increases the total number of mesh cells to more than <b><u>230 million</u></b>.

Typical Performance <table><tr><td>[[Image: 320 MCellsHood mount mesh detail.png|thumb|left|480px| The details of the Yee mesh of the vehicle structure generated by EM.Tempo around the location of the patch antenna on the hood.]]</std></tr></table>

The thread factor setting essentially tells the FDTD engine how many CPU threads to use during <table><tr><td>[[EMImage:Hood nearfield.Tempo]]'s timepng|thumb|left|640px| The dB-marching loop. For a given system, some experimentation may be needed to determine the best number of threads to use. In many cases, using half scale electric field distribution of the available hardware concurrency works well. This comes from vehicle-antenna combination structure in the fact that many modern processors often have two cores per memory portvertical ZX plane. In other words, for many problems, the FDTD solver cannot load and store data from CPU memory quickly enough to use all the available threads or hardware concurrency. The extra threads remain idle waiting for the data, and a performance hit is incurred due to the increased thread context switching. [[EM.Cube]] will attempt use a version of the FDTD engine optimized for use with Intel's AVX instruction set, which provides a significant performance boost. If AVX is unavailable, a less optimal version of the engine will be used alternatively. </td></tr></table>

[[Image:Roof The figure below shows the 3D far-fieldradiation pattern of the installed patch antenna on the vehicle's hood.png|thumb|left|400px|]]For this simulation, the far-field angular resolution was set to 2.5&deg; along both azimuth and elevation directions.

[[Image:Roof mesh.png|thumb|left|400px|]]<table><tr>[[Image:Roof mesh settings.png|thumb|left|400px|]]<td>[[Image:Roof mesh settings advancedHood pattern.png|thumb|left|400px640px|]] [[Image:Roof 3D far-field radiation pattern of the vehicle-antenna combination structure, with the patchantenna installed on the vehicle's hood.png|thumb|left|400px|]]</td>[[Image:Roof patch mesh.png|thumb|left|400px|]]</tr> [[Image:Roof pattern.png|thumb|left|400px|]] [[Image:Roof wheel mat.png|thumb|left|400px|]]</table>

[[Image:Roof wheel mat selectThe figures below show the 2D polar radiation patterns of the hood-mounted patch antenna in the principal YZ and ZX planes. Comparing these graphs with those of the two previous cases shows significant reflection and diffraction effects at the new location of the patch antenna.png|thumb|left|400px|]]

<table><tr><td>[[Image:Roof Hood yz cut.png|thumb|left|400px480px|]] [[Image:Roof zx cut2D linear-scale polar radiation pattern of the hood-mounted patch antenna in the YZ plane.png|thumb|left|400px|]] <br clear="all"/td> =Patch on Hood= Simulation Information: Mesh size: 230 million cells Farfield Resolution: 2.5 degrees Simulation Time: 5 hours, 25 minutes Typical Performance : 320 MCells</str><tr>Power Threshold: -40 dB Thread Factor: 8 <td>[[Image:Hood mountzx cut.png|thumb|left|400px480px|2D linear-scale polar radiation pattern of the hood-mounted patch antenna in the ZX plane.]]</td>[[Image:Hood mount mesh detail.png|thumb|left|400px|]]</tr></table>

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