alffnot
Member level 1
hfss s11
i have been trying to compare momentum simulation to hfss simulations. i am using a directional coupler, and when i simulate using both programs i am getting all the S-params to match very closely, but S11 is very different. i'll attach the plot, dashed lines are the hfss params, and solid lines are momentum(ignore the colors, they got screwed up in matlab). i really can't figure out why the s11 param is so much different. i have tried as many different mesh's and different port sizes in hfss and i can't get them to change to much.
layout is just 2 parralel microstrips, with spacing of 1.5mm on substrate of 1mm hieght, dieletric const=4.5, strips are 1.81mm each. i am wondering if i should got out 90degrees from each ustrip so when i set up the ports they will be far apart from each other, but i didn't want to do this unless i had to becuase i didn't want to add anything more into the circuit that i didn't have to, i was just trying to keep it simple
just getting frustrated, wonder if anyone has anyideas why this is this way,. thanks for the help
i have been trying to compare momentum simulation to hfss simulations. i am using a directional coupler, and when i simulate using both programs i am getting all the S-params to match very closely, but S11 is very different. i'll attach the plot, dashed lines are the hfss params, and solid lines are momentum(ignore the colors, they got screwed up in matlab). i really can't figure out why the s11 param is so much different. i have tried as many different mesh's and different port sizes in hfss and i can't get them to change to much.
layout is just 2 parralel microstrips, with spacing of 1.5mm on substrate of 1mm hieght, dieletric const=4.5, strips are 1.81mm each. i am wondering if i should got out 90degrees from each ustrip so when i set up the ports they will be far apart from each other, but i didn't want to do this unless i had to becuase i didn't want to add anything more into the circuit that i didn't have to, i was just trying to keep it simple
just getting frustrated, wonder if anyone has anyideas why this is this way,. thanks for the help