I want to obtain dispersion diagram of the periodic structure with CST. The structure is finite in transverse direction: "A row of pins which consists 7 pins laid under a metallic plate. The entire row is laid between two metallic sidewalls. the row of pins together with the sidewalls are repeated along the longitudinal direction periodically". But when I simulate the structure with CST Eigenmode Solver, I obtain two additional modes compared to a paper's result. Can anyone help me with this problem please?
Can you please tell me how did you plot the dispersion diagram of this structure using cst?
@Libimol V.A : First you should draw the geometry of one unit cell of your structure. Second set periodic boundary on the sides which the structure is periodically repeated perpendicular to them. By setting the phase difference between two opposing sides that are set as periodic boundary as a variable parameter, you can use parameter sweep of the Eigenmode solver. Sweep the phase parameter from 0 to 180 degree. For each value of phase difference Eigenmode solver obtains a frequency and phase difference is proportional to the propagation constant. So you will have the dispersion diagram in this way.
@Parinaz Sadri-Thank you very much for this detailed reply..
Now I got the idea to plot dispersion diagram.
I tried to simulate the Sievenpiper mushroom structure.But I got struck to draw the vias and set the boundary condition..
What I followed is
1.I drew the cylindrical via.
2.I subtracted the structure from dielectric.
3.Since the vias have metallization inside,how can i assign the perfect conductor boundary to it.
Expecting some help from you in this regard.
Thanks in advance.
@Parinaz Sadri,
One more doubt:-
I tried simulating the structure to get dispersion diagram.
By using single mode,i got TM wave characteristics.
But when I tried the same structure for 2 modes(to obtain TE characterstics)-Both TE and TM modes where corrupted,
Can you please tell me how did you obtained TE wave characteristics from hfss simulation.
Thanks in advance..
I obtained the dispersion diagram in CST. This time I compared the results by another paper's results and there was no difference between them. But I never had a problem like the one you mentioned. Sorry, I do not know how to solve this problem.
Salim Lamar: I was working with CST 2011. Yes, this version has the eigenmode solver.
Hi;
Have you known about this Eq?
beta = acos( (1-(S12*s21)+(s11*s22))/(2*s21)
then *180/pi to get it in degrees.
Im not sure this Eq is correct or not?!
this Eq is a way for draw the dispersion diagram
Hi
Parinaz Sadri-Moshkenani : I have simulated the dispersion diagram with CST and i get results that is similar to the results in the paper i am simulating.
But i don't know the relation between beta(propagation constant) and phaseX. Can you tell me how these two parameters are related to each other?
I have attached the results for you.
- Badges
- Science topic
- Similar topics
- Physical Sciences
- Electromagnetics
- Electromagnetic Fields