You couple two or more sources using the '''Port Definition Dialog'''. To do so, you need to change the default port assignments. First, delete all the ports that are to be coupled from the Port List of the dialog. Then, define a new port by clicking the '''Add''' button of the dialog. This opens up the Add Port dialog, which consists of two tables: '''Available''' sources on the left and '''Associated''' sources on the right. A right arrow ('''-->''') button and a left arrow ('''<--''') button let you move the sources freely between these two tables. You will see in the "Available" table a list of all the sources that you deleted earlier. You may even see more available sources. Select all the sources that you want to couple and move them to the "Associated" table on the right. You can make multiple selections using the keyboard's '''Shift''' and '''Ctrl''' keys. Closing the Add Port dialog returns you to the Port Definition dialog, where you will now see the names of all the coupled sources next to the name of the newly added port.
{{Note|It is your responsibility to set up coupled ports and coupled [[Transmission Lines|[[Transmission Lines|[[Transmission Lines|[[Transmission Lines|[[Transmission Lines|[[Transmission Lines|[[Transmission Lines|[[Transmission Lines|[[Transmission Lines|[[Transmission Lines|[[Transmission Lines|[[Transmission Lines|transmission lines]]]]]]]]]]]]]]]]]]]]]]]] properly. For example, to excite the desirable odd mode of a coplanar waveguide (CPW), you need to create two rectangular slots parallel to and aligned with each other and place two gap sources on them with the same offsets and opposite polarities. To excite the even mode of the CPW, you use the same polarity for the two collocated gap sources. Whether you define a coupled port for the CPW or not, the right definition of sources will excite the proper mode. The couple ports are needed only for correct calculation of the port characteristics.}}
[[File:PMOM51(2).png|800px]]
== Working with Planar MoM Simulation Data ==
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=== Planar Module's Output Simulation Data ===
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Depending on the source type and the types of observables defined in a project, a number of output data are generated at the end of a planar MoM simulation. Some of these data are 2D by nature and some are 3D. The output simulation data generated by [[EM.Cube]]'s [[Planar Module]] can be categorized into the following groups:
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* '''Port Characteristics''': S, Z and Y [[Parameters]] and Voltage Standing Wave Ratio (VSWR)
* '''Radiation Characteristics''': Radiation Patterns, Directivity, Total Radiated Power, Axial Ratio, Main Beam Theta and Phi, Radiation Efficiency, Half Power Beam Width (HPBW), Maximum Side Lobe Level (SLL), First Null Level (FNL), Front-to-Back Ratio (FBR), etc.
* '''Scattering Characteristics''': Bi-static and Mono-static Radar Cross Section (RCS)
* '''Periodic Characteristics''': Reflection and Transmission Coefficients
* '''Current Distributions''': Electric and magnetic current amplitude and phase on all metal and slot traces and embedded objects
* '''Near-Field Distributions''': Electric and magnetic field amplitude and phase on specified planes and their central axes
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At the end of an analysis, the 2D quantities usually have a single value that is written into an ASCII data file. Complex-valued quantities are written into complex data files with a "'''.CPX'''" extension. Real-valued quantities are written into real data files with a "'''.DAT'''" extension. Polar 2D radiation pattern data and some other radiation characteristics are written into angular data files with a "'''.ANG'''" extension. In this latter file type, polar data are stored as functions of an angle expressed in degrees. At the end of a sweep simulation of one of the many types available (frequency, angular, parametric, etc.), the ASCII output data files are populated with rows that correspond to the samples of the sweep variable(s). If a sweep simulation involves N sweep [[variables]], then the first N columns of the output data files show the samples of those sweep [[variables]]. All the 2D data files are listed in the '''2D Data Files''' tab of [[EM.Cube]]'s '''Data Manager'''. You can view the contents of these data files by selecting their row in the data manager and clicking the '''View''' button of the dialog.
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3D output data, on the other hand, are defined as functions of the space coordinates and are usually of vectorial nature. Cartesian-type and mesh-type data such as current distributions and near-field field distributions are expressed as functions of the Cartesian (X, Y, Z) coordinates. Spherical-type data like far-field radiation patterns and RCS are expressed as functions of the spherical angles (θ, φ). The 3D radiation patterns are written into a file with a "'''.RAD'''" extension. This file contains the complex values of the θ- and φ-components of the far-zone electric field (E<sub>θ</sub> and E<sub>φ</sub>) as well as the total far field magnitude as functions of the spherical observation angles θ and φ. The 3D RCS patterns are written into a file with a "'''.RCS'''" extension. This file contains the real values of the θ- and φ-polarized RCS values as well as the total RCS as functions of the spherical observation angles θ and φ. The current distributions are written into data files with a "'''.CUR'''" extension. They contain the real and imaginary parts of the X, Y and Z components of electric ('''J''') and magnetic ('''M''') current on each cells together with the definition of all the node coordinates and node indices of the cells. The near-field distributions are written into data files with a "'''.SEN'''" extension. They contain the amplitude and phase of the X, Y and Z components of electric ('''E''') and magnetic ('''H''') fields as functions of the coordinates of sampling points. All the 3D data files are listed in the '''3D Data Files''' tab of [[EM.Cube]]'s '''Data Manager'''. You can view the contents of these data files by selecting their row in the data manager and clicking the '''View''' button of the dialog.
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[[File:PMOM138.png]]
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Figure 1: The 3D Data Files tab of [[EM.Cube]]'s Data Manager.
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[[File:PMOM139.png|800px]]
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Figure 2: Viewing the contents of a mesh-type 3D data file in Data Manager.
=== Visualizing Current Distributions ===
Figure 2: An example of the 3D mono-static radar cross section plot of a patch antenna.
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=== Planar Module's Output Simulation Data ===
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Depending on the source type and the types of observables defined in a project, a number of output data are generated at the end of a planar MoM simulation. Some of these data are 2D by nature and some are 3D. The output simulation data generated by [[EM.Cube]]'s [[Planar Module]] can be categorized into the following groups:
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* '''Port Characteristics''': S, Z and Y [[Parameters]] and Voltage Standing Wave Ratio (VSWR)
* '''Radiation Characteristics''': Radiation Patterns, Directivity, Total Radiated Power, Axial Ratio, Main Beam Theta and Phi, Radiation Efficiency, Half Power Beam Width (HPBW), Maximum Side Lobe Level (SLL), First Null Level (FNL), Front-to-Back Ratio (FBR), etc.
* '''Scattering Characteristics''': Bi-static and Mono-static Radar Cross Section (RCS)
* '''Periodic Characteristics''': Reflection and Transmission Coefficients
* '''Current Distributions''': Electric and magnetic current amplitude and phase on all metal and slot traces and embedded objects
* '''Near-Field Distributions''': Electric and magnetic field amplitude and phase on specified planes and their central axes
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At the end of an analysis, the 2D quantities usually have a single value that is written into an ASCII data file. Complex-valued quantities are written into complex data files with a "'''.CPX'''" extension. Real-valued quantities are written into real data files with a "'''.DAT'''" extension. Polar 2D radiation pattern data and some other radiation characteristics are written into angular data files with a "'''.ANG'''" extension. In this latter file type, polar data are stored as functions of an angle expressed in degrees. At the end of a sweep simulation of one of the many types available (frequency, angular, parametric, etc.), the ASCII output data files are populated with rows that correspond to the samples of the sweep variable(s). If a sweep simulation involves N sweep [[variables]], then the first N columns of the output data files show the samples of those sweep [[variables]]. All the 2D data files are listed in the '''2D Data Files''' tab of [[EM.Cube]]'s '''Data Manager'''. You can view the contents of these data files by selecting their row in the data manager and clicking the '''View''' button of the dialog.
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3D output data, on the other hand, are defined as functions of the space coordinates and are usually of vectorial nature. Cartesian-type and mesh-type data such as current distributions and near-field field distributions are expressed as functions of the Cartesian (X, Y, Z) coordinates. Spherical-type data like far-field radiation patterns and RCS are expressed as functions of the spherical angles (θ, φ). The 3D radiation patterns are written into a file with a "'''.RAD'''" extension. This file contains the complex values of the θ- and φ-components of the far-zone electric field (E<sub>θ</sub> and E<sub>φ</sub>) as well as the total far field magnitude as functions of the spherical observation angles θ and φ. The 3D RCS patterns are written into a file with a "'''.RCS'''" extension. This file contains the real values of the θ- and φ-polarized RCS values as well as the total RCS as functions of the spherical observation angles θ and φ. The current distributions are written into data files with a "'''.CUR'''" extension. They contain the real and imaginary parts of the X, Y and Z components of electric ('''J''') and magnetic ('''M''') current on each cells together with the definition of all the node coordinates and node indices of the cells. The near-field distributions are written into data files with a "'''.SEN'''" extension. They contain the amplitude and phase of the X, Y and Z components of electric ('''E''') and magnetic ('''H''') fields as functions of the coordinates of sampling points. All the 3D data files are listed in the '''3D Data Files''' tab of [[EM.Cube]]'s '''Data Manager'''. You can view the contents of these data files by selecting their row in the data manager and clicking the '''View''' button of the dialog.
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[[File:PMOM138.png]]
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Figure 1: The 3D Data Files tab of [[EM.Cube]]'s Data Manager.
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[[File:PMOM139.png|800px]]
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Figure 2: Viewing the contents of a mesh-type 3D data file in Data Manager.
=== Viewing & Visualizing Various Output Data Types ===