<td>
[[Image:PROP MAN4.png|thumb|left|720px|The imported terrain model of Mount Whitney shown in EM.Terrano's project workspace under a terrain group called "Terrain_1".]]
</td>
</tr>
</table>
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=== Adjustment of Block Elevation on Underlying Terrain Surfaces ===
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In [[EM.Terrano]], buildings and all other CAD 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 z = 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.
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{{Note| You have to make sure that the resolution of your terrain, its variation scale and building dimensions are all comparable. Otherwise, on a rapidly varying high-resolution terrain, you will have buildings whose bottoms touch the terrain only at a few points and parts of them hang in the air.}}
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<table>
<tr>
<td>
[[Image:PROP MAN5.png|thumb|left|480px|The property dialog of impenetrable surface showing the terrain elevation adjustment box checked.]]
</td>
</tr>
</table>
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<table>
<tr>
<td>
[[Image:PROP MAN6.png|thumb|left|480px|A set of buildings on an undulating terrain without elevation adjustment.]]
</td>
</tr>
<tr>
<td>
[[Image:PROP MAN7.png|thumb|left|480px|The set of buildings on the undulating terrain after elevation adjustment.]]
</td>
</tr>
</tr>
</table>
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== Defining Sources & Observables for Your SBR Simulation ==
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Like every other electromagnetic solver, EM.Terrano's SBR ray tracer requires an excitation source and one or more observables for generation of simulation data. EM.Terrano offers several types of sources and observables for a SBR simulation. You can mix and match different source types and observable types depending on the requirements of your modeling problem. The available source types are (click on each type to learn more about it):
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* '''[[#Defining Transmitter Sets | Transmitter]]'''
* '''[[#Defining_a_Hertzian_Dipole_Source | Hertzian Dipole]]'''
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The available observables types are (click on each type to learn more about it):
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* '''[[#Defining Receiver Sets | Receiver]]'''
* '''[[#Defining_a_Field_Sensor | Field Sensor]]'''
* '''[[#Computing_Radiation_Patterns_In_SBR | Far Field Radiation Pattern]]'''
* '''[[Hybrid_Modeling_using_Multiple_Simulation_Engines#Generating_Huygens_Surface_Data | Huygens Surface]]'''
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A short dipole source is the simplest type of excitation for your propagation scene. A short dipole has an almost "omni-directional" radiation pattern, and is the closest thing to an isotropic radiator. EM.Terrano does not provide a theoretical/hypothetical isotropic transmitter because its SBR solver is fully polarimetric and requires a real physical radiator for ray generation. A transmitter is a more sophisticated source that requires a base point as well as an imported radiation pattern file with a '''.RAD''' file extension.
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Of the above list of EM.Terrano's observables types, receivers are the ones you would typically use for your propagation scenes. Unlike a transmitter, a receiver by default does not require an imported radiation pattern file. A default receiver is assumed to be polarization-matched to the incoming ray. The other three observable types, field sensor, far fields and Huygens surface are primarily used in applications that utilize EM.Terrano as an asymptotic electromagnetic field solver. The Huygens surface observable is primarily used for [[Hybrid Modeling using Multiple Simulation Engines|hybrid modeling using multiple simulation engines]].
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{{Note| In order to define either transmitters or receivers, first you have to define base points. For a transmitter, you additionally need to import a radiation pattern file from one of [[EM.Cube]]'s other computational modules.}}
== Defining Transmitters & Receivers for Your Propagation Scene ==
</tr>
</table>
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== Defining Sources & Observables for Your SBR Simulation ==
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Like every other electromagnetic solver, EM.Terrano's SBR ray tracer requires an excitation source and one or more observables for generation of simulation data. EM.Terrano offers several types of sources and observables for a SBR simulation. You can mix and match different source types and observable types depending on the requirements of your modeling problem. The available source types are (click on each type to learn more about it):
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* '''[[#Defining Transmitter Sets | Transmitter]]'''
* '''[[#Defining_a_Hertzian_Dipole_Source | Hertzian Dipole]]'''
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The available observables types are (click on each type to learn more about it):
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* '''[[#Defining Receiver Sets | Receiver]]'''
* '''[[#Defining_a_Field_Sensor | Field Sensor]]'''
* '''[[#Computing_Radiation_Patterns_In_SBR | Far Field Radiation Pattern]]'''
* '''[[Hybrid_Modeling_using_Multiple_Simulation_Engines#Generating_Huygens_Surface_Data | Huygens Surface]]'''
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A short dipole source is the simplest type of excitation for your propagation scene. A short dipole has an almost "omni-directional" radiation pattern, and is the closest thing to an isotropic radiator. EM.Terrano does not provide a theoretical/hypothetical isotropic transmitter because its SBR solver is fully polarimetric and requires a real physical radiator for ray generation. A transmitter is a more sophisticated source that requires a base point as well as an imported radiation pattern file with a '''.RAD''' file extension.
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Of the above list of EM.Terrano's observables types, receivers are the ones you would typically use for your propagation scenes. Unlike a transmitter, a receiver by default does not require an imported radiation pattern file. A default receiver is assumed to be polarization-matched to the incoming ray. The other three observable types, field sensor, far fields and Huygens surface are primarily used in applications that utilize EM.Terrano as an asymptotic electromagnetic field solver. The Huygens surface observable is primarily used for [[Hybrid Modeling using Multiple Simulation Engines|hybrid modeling using multiple simulation engines]].
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{{Note| In order to define either transmitters or receivers, first you have to define base points. For a transmitter, you additionally need to import a radiation pattern file from one of [[EM.Cube]]'s other computational modules.}}
== Using EM.Terrano as an Asymptotic Field Solver ==