RL-GO Settings

A number of optional settings are available when using ray launching geometrical optics (RL-GO) to solve parts of the model.

On the Solve/Run tab, in the Solution settings group, click the  Solver settings icon. On the Solver settings dialog, click the High frequency tab.

Decouple from MoM solutions
This option ignores the RL-GO regions when calculating the MoM currents.
Tip: Where the MoM and RL-GO regions are electrically far apart and far field quantities are of interest, decouple the solution to reduce the memory and run-time without sacrificing the accuracy of the results.
Maximum number of ray interactions
This option limits the number of ray interactions (reflection and diffraction combined). For example, if this parameter is set to 3, a ray can have three reflections, or two reflections and a transmission. If left empty, then the maximum number if ray interactions is determined automatically.
Edge and wedge diffractions
This option takes into account the diffraction on edges and wedges.
Export ray file for post-processing
This option exports the rays during the RL-GO solution process to a .ray file. The ray-tracing information is also stored in the .bof and you can view the rays in POSTFEKO.
Note: Large .ray files are possible when the MoM and RL-GO solution have not been decoupled and the MoM region contains a large number of mesh elements.
Adaptive ray launching settings
This option allows you to control the density of the rays launched, as well as when to stop tracing a ray based on the ray's decay.
  • High (more rays): The ray density is high. Results take longer to obtain but with higher accuracy.
  • Normal (default): The default ray density setting.
  • Low (fewer rays): The ray density is low. Results are fast to obtain but with lower accuracy.
    Note: Start with Low (fewer rays) which uses the least computational resources. When the model appears to be performing as expected, use a higher setting.
Fixed grid increments
This option allows you to specify the ϕ and θ angular resolution for ray launching and the increments for the parallel ray front in the U direction and V direction. Though the run-time for a problem involving RL-GO may be decreased using this option, it may influence the accuracy of the solution.
Note: Manual specification of the angular increment should only be used under specific conditions after the implications have been carefully considered.