Faceted UTD

With this option the UTD parameters for faceted UTD for planar and curved faces are specified.

Figure 1. The UT - Specify the UTD/RL-GO parameters dialog, set to Faceted UTD.


Use faceted UTD on all surfaces with label
The label to which the faceted UTD should be applied
(optionally) up to label
The label up to which the faceted UTD should be applied. Faceted UTD will not be applied to labels outside of the range between this field and the label in the previous field.
Max no. of ray interactions
This parameter gives the maximal number of ray-interactions. If for example, the parameter is set to 3, a ray can have 3 reflections. If set to 0, only direct rays are taken into account.
Export ray file for post-processing
When this item is checked the ray information is exported to the .bof and .ray files. Activate this option if ray paths are to be displayed in POSTFEKO where the ray information is read from the .bof file. The exported ray information may result in a large .ray file and a dramatic increase in the .bof file size. For parallel runs the run-time can also increase significantly when exporting ray data.
The following abbreviations are used in the .ray file and POSTFEKO:
  • ยท: Creeping wave intermediate point on geometry surface
  • B: Diffraction at an edge
  • D: Diffraction at a corner (of a wedge)
  • E: Diffraction at a corner (of an edge)
  • K: Diffraction at a wedge
  • Q: Source point
  • R: Reflection
  • S: Observation point
  • C: Creeping wave attaching and shedding point on geometry surface
  • V: Reflection at the shadow boundary of a creeping wave
Ray contributions
Determines which ray contributions to take into account.
Direct field
Direct rays are taken into account.
Surface reflection
Rays reflected from planar and curved surfaces are taken into account.
Edge and wedge diffraction
Diffraction on edges and wedges are taken into account.
Creeping waves
Creeping waves on curved surfaces.
Increasing the type and number of ray interactions increases accuracy and the computation time. The user should therefore make a compromise between the number of ray interactions and the ray contributions. Choices made in this card should be made on physical considerations to get optimal use from the UTD formulation.

The following restrictions apply for the faceted UTD:

  • Only PEC structures are allowed (no dielectric bodies, thin dielectric sheets or coatings are allowed).
  • Only planar triangles are allowed.
  • The faceted UTD may not be used in conjunction with other solution methods.