ing_2012
Newbie level 6

Hello everybody,
I'm trying to simulate an aperture coupled patch antenna(rectangular)at the millimeter band with HFSS, i made my 50 ohm feed_line into 30um substrate, and my ground with the aperture above it.
First of all, i triyed to simulate with a wave port (sized as hport=6 times substrate height and Wport=5 times feedline width), this give me good resuls (S11=-22 db)
The problem is when i tried with lumped port , the results changed, there is shifting in the resonant frequency and bad S11 (-11 db). Why there are no agreement between the two tools?
I attached two pictures one about the antenna with the wave port and the other with the lumped port.


Which one must be more accurate?
thanks for any help
I'm trying to simulate an aperture coupled patch antenna(rectangular)at the millimeter band with HFSS, i made my 50 ohm feed_line into 30um substrate, and my ground with the aperture above it.
First of all, i triyed to simulate with a wave port (sized as hport=6 times substrate height and Wport=5 times feedline width), this give me good resuls (S11=-22 db)
The problem is when i tried with lumped port , the results changed, there is shifting in the resonant frequency and bad S11 (-11 db). Why there are no agreement between the two tools?
I attached two pictures one about the antenna with the wave port and the other with the lumped port.


Which one must be more accurate?
thanks for any help