June 13, 2023 at 11:43 pm
Guilin Sun
Ansys Employee

It should be from the frequecy sweep in FDE, and then choose "export data" in ldf file.

The file contains neff data at different frequencies for INTERCONNECT simulation.

https://optics.ansys.com/hc/en-us/articles/360042800453-Waveguide-FDE-