Reply To: Evanescent Mode Waveguide Simulation in HFSS

[zlEM]

Hi,

 

Thank you for your suggestions. Allow me to provide more details regarding my design. The simulation is intended to model an open-ended waveguide section excited by a waveport operating in the evanescent mode. The goal is to obtain information about the input impedance looking into the waveguide section of a given length terminated by free space and the radiation properties of this open-ended waveguide. The frequency of interest is below the cutoff of the waveguide's dominant mode. In addition, I want to obtain the information for different lengths. Therefore, I was hoping deembedding could be used so that I only need to simulate once for an abitrary length then for other values I can simply do deembedding to shift the reference plane. The simulation model and setup are shown below:

Some discrepancies are observed in the radiation patterns from the two simulations. The "Include Port Post Processing Effects" option is checked in "Excitations". In the 3-mm case, patterns at different frequencies almost overlap while in the 20-mm case, patterns only exist at 80 and 81 GHz. The discrepancies here make me wonder whether deembedding can be used in my design for the purpose mentioned above.