Continue to Site

Welcome to EDAboard.com

Welcome to our site! EDAboard.com is an international Electronics Discussion Forum focused on EDA software, circuits, schematics, books, theory, papers, asic, pld, 8051, DSP, Network, RF, Analog Design, PCB, Service Manuals... and a whole lot more! To participate you need to register. Registration is free. Click here to register now.

S12 greater than 0 dB for a transmission line !!

Status
Not open for further replies.

maxwel90

Newbie level 3
Joined
Apr 24, 2019
Messages
3
Helped
0
Reputation
0
Reaction score
0
Trophy points
1
Activity points
23
Hi everyone,

I tried to simulate a transmission line above a rectangular metallic sheet using the "integral equation solver", and finally i got an S12 parameter which is greater than 0 dB at the resonnant frenquencies of the line.

When i use the "time domain solver" i obtain good results.

Does anyone have any idea how to solve this problem ?

By the way, i used the discret ports.

Thank you for your support !
 

There are so many different EM solvers ... it might help if you mention the simulation tool that you used.
 

Don't sure if I can help, but maybe the positive S12 is due to an upper resonance? Be careful to not create a metal (PEC) cavity with the boundaries near the model, or it could lead to unwanted resonances.

Anyway, why are you trying to simulate with the Integral Equation solver? The TDS with the adaptive meshing should be more than enougth (and fast). Also, for TL and planar structures, I suggest using Waveguide ports.

Cheers,

AMD
 

@anddab thank you for your answer. Indeed the TDS with adaptive meshing is faster than the integral equation solver, but the point is that i want to compare the MoM method (solved in the frequency domain) with a frequency model i developped for transmission lines.

Now i am using the integral equation solver, it's difficult to get good results. We have to pay attention to the meshing features :

- With 5 cells per wavelength, i could get good results in reasonable calculation time.

- With 10 cells per wavelength, i couldn't get good results, sometimes the solver stop the calculation displaying this message (could not solve equation system).

By the way, all the boundaries are open space.

Kindly,
 

Status
Not open for further replies.

Part and Inventory Search

Welcome to EDABoard.com

Sponsor

Back
Top