alffnot
Member level 1
coupler hfss
I am trying to simulate in HFSS a microstrip coupler, but it has 90 degree bends as the feed point. see attached picture. I have simulated alot of couplers before, but they have always had feed points on the same side of the substrate so I would normally use a wave port. but with the 90 degree bends I figure a lumped port would work becuase there isn't coupling at the ports becuase they are far apart. But with the lumped ports i keep running into an error, it tells me that the T-matrix is very close to unity and doesn't solve it. if i set the solution type to be driven modal instead of terminal it will at least solve but it is definiatly not the right solution, S21 come out to be around -200dB and S11 is nearly 0. I have simulated the same structure without the 90 degree bends and it works just fine
I am trying to simulate in HFSS a microstrip coupler, but it has 90 degree bends as the feed point. see attached picture. I have simulated alot of couplers before, but they have always had feed points on the same side of the substrate so I would normally use a wave port. but with the 90 degree bends I figure a lumped port would work becuase there isn't coupling at the ports becuase they are far apart. But with the lumped ports i keep running into an error, it tells me that the T-matrix is very close to unity and doesn't solve it. if i set the solution type to be driven modal instead of terminal it will at least solve but it is definiatly not the right solution, S21 come out to be around -200dB and S11 is nearly 0. I have simulated the same structure without the 90 degree bends and it works just fine