</table>
== Running an SBR Simulation Ray Tracing Simulations ==
=== SBR Simulation Types ===
[[Image:PROP12.png|thumb|400px|EM.Terrano's Simulation Run dialog.]]
Once you have set up your propagation scene in EM.Terrano offers three types of and have defined sources/transmitters and observables/receivers for your scene, you are ready to run a ray tracing simulationssimulation. EM.Terrano offers thee simulation modes (click on each type to learn more about it):
* '''[[#Running a Single-Frequency SBR Analysis| Single-Frequency Analysis]]'''* '''[[Parametric_Modeling,_Sweep_%26_Optimization#Running_Frequency_Sweep_Simulations_in_EM.Cube | Frequency Sweep]]''' * '''[[Parametric_Modeling,_Sweep_%26_Optimization#Running_Parametric_Sweep_Simulations_in_EM.Cube | Parametric Sweep]]'''Â You can set the simulation mode from EM.Terrano's "Simulation Run Dialog". A single-frequency analysis is a single-run simulation. The two other simulation modes in the above list are considered multi-run simulations. If you run a simulation without having defined any observables, no data will be generated at the end of the simulation. In multi-run simulation modes, certain [[parameters]] are varied and a collection of simulation data files are generated. At the end of a sweep simulation, you can graph the simulation results in EM.Grid or you can animate the 3D simulation data from the navigation tree. Â {{Note| EM.Terrano's frequency sweep simulations are very fast because the geometrical optics (ray tracing) part of the simulation is frequency-independent.}}Â === Running a Single-Frequency SBR Analysis ===
A single-frequency SBR analysis is the simplest type of ray tracing simulation and involves the following steps:
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 simulating results, but they also increase the computation time. The SBR Engine Settings dialog also shows the required '''Minimum Angular Resolution''' in degrees in a greyed-out box. This number is calculated based on the overall extents of your computational domain as well as the SBR mesh resolution. To see this value, you have to generate the SBR mesh first. Keeping the angular resolution of your project above this threshold value makes sure that the small mesh facets at very large distances from the source would not miss any impinging ray tubes during the simulation.
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=== Running an SBR Frequency Sweep ===
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[[Image:prop_run10.png|thumb|300px|EM.Terrano's Frequency Settings dialog.]]
By default, EM.Terrano performs a single-frequency analysis. You set the operational frequency of a SBR simulation in the project's '''Frequency Dialog''', which can be accessed in a number of ways:
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* By clicking the '''Frequency''' [[File:freq_icon.png]] button of the '''Simulate Toolbar'''.
* By selecting '''Simulate > Frequency Settings...''' from the Menu Bar.
* Using the keyboard shortcut {{key|Ctrl+F}}.
* By double clicking the frequency section (box) of the '''Status Bar'''.
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You can also select the '''Frequency Sweep''' option in the '''Simulation Mode''' dropdown list of the '''Run Dialog'''. Click the {{key|Settings}} button on the right side of this dropdown list to open up the Frequency Settings Dialog. In this dialog you have to set the value of '''Start Frequency''', '''End Frequency''' and '''Number of Samples''' for you frequency sweep. Once you click the {{key|Run}} button, EM.Terrano performs a frequency sweep by assigning each of the frequency samples as the current operational frequency and running the SBR simulation engine at each frequency. All the simulation data at all frequency samples are saved into the output data files including "SBR_results.RTOUT".
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{{Note| EM.Terrano's frequency sweep simulations are very fast because the geometrical optics (ray tracing) part of the simulation is frequency-independent.}}
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[[Image:Info_icon.png|40px]] Click here to learn more about '''[[Parametric_Modeling,_Sweep_%26_Optimization#Running_Parametric_Sweep_Simulations_in_EM.Cube | Running Parametric Sweep Simulations in EM.Cube]]'''.
== Working with SBR Simulation Data ==