hi,
I have a similar probem.
I want to simulte CPW ,and I expect the structure of CPW give the standard impedance 50 Ohm.Because the substrate is thick silicon, lumped port seem
to be the better choice.
But the lumped port will not give the impedance result, and I have to provide impedance for the S-parameter results.
How can I solve this problem? Can anyone give me some suggestion?
I give you an advice here, after finished your simulation, you must select port to plot vector-E, to make sure the E field is right. if it is not right, you can change the dimension of port. hope this helpful!
CPW transmission lines often cause significant grief as they are "mode rich". I generally use wave ports in my analysis. Read the section on Impedance calculation in HFSS help. You will probably want to use the Zpi form and an impedance line. Make sure the mode and impedance line make sense by examining the port field configuration for each mode. You don't say if you are using single ended or differential CPW lines or if you have a lower ground plane. If the lines are differential, are they tightly (close) or loosely(wide spacing) coupled? Depending on these details the situation will change.
When all is done, I like to compare the results to Polar Instrument's calculator (or similar tool) to confirm that the results are reasonable. I specifically do not mean to imply that I think Polar is a better tool. I use it as a sanity check to help detect a blunder.
hi,
i have a question. if we use wave port mode for cpw feed line, how many modes do we need to describe? one or two? if we use one mode , the field in that side of antenna feed line described will b more strong than other.
I have a similar problem. I m simulating a cpw fed patch antenna. I m using a waveport. But the fields at the waveport dont correspond to CPW mode. I have tried varying the size of the waveport....but with no improvement.
Has anyone successfully simulated CPW fed antennas in HFSS. Does HFSS handle CPW properly? Could someone tell me the correct steps in setting the CPW feed.