Hi,
I am doing a simulation of free space. My Comsol version is 4.1
My goal is to find transmission and reflection coefficients in order to determine phase of reflection or transmission.
I know how to find them by using 'Lumped Port' at front and back boundaries of the space, since I can access to scattering parameters S11, and S12, ... . But in this method of simulation, it looks like I have to use PEC and PMC at side boundaries in order to have a definition of polarization of incident filed.
Now, this is the problem:
I am going to use periodic boundary at side boundaries with linear polarization and later I will apply circular polarization for my next steps. Therefore 'Lumped Port' is not useful.
I saw that some people do simulation with 'Port' at front and back boundaries. The good point of this is that in 'Port' boundaries I can define circular polarization or any kind of polarizations. I am trying to do same simulation as they do, but my simulation makes error. It does not matter whether I use PEC, PMC boundaries or Periodic boundaries or even circular polarization or linear. In any case I am not able to simulate. It makes the same error always. I am not even sure if I can access to scattering parameters in this 'Port' method of simulation in order to calculate phase of transmitted and reflected waves.
This the error:
"Failed to find a solution.
Singular matrix.
For mesh-case 0 there are 1 void equations (empty rows in matrix) for the variable mod1.emw.S2x
at coordinates: (0,0,0), ...
and similarly for the degrees of freedom (empty columns in matrix)
Returned solution has not converged."
I appreciate if somebody can help me. I attached my file either in case if you would like to look at that and let me know what is wrong with my simulation.
I am doing a simulation of free space. My Comsol version is 4.1
My goal is to find transmission and reflection coefficients in order to determine phase of reflection or transmission.
I know how to find them by using 'Lumped Port' at front and back boundaries of the space, since I can access to scattering parameters S11, and S12, ... . But in this method of simulation, it looks like I have to use PEC and PMC at side boundaries in order to have a definition of polarization of incident filed.
Now, this is the problem:
I am going to use periodic boundary at side boundaries with linear polarization and later I will apply circular polarization for my next steps. Therefore 'Lumped Port' is not useful.
I saw that some people do simulation with 'Port' at front and back boundaries. The good point of this is that in 'Port' boundaries I can define circular polarization or any kind of polarizations. I am trying to do same simulation as they do, but my simulation makes error. It does not matter whether I use PEC, PMC boundaries or Periodic boundaries or even circular polarization or linear. In any case I am not able to simulate. It makes the same error always. I am not even sure if I can access to scattering parameters in this 'Port' method of simulation in order to calculate phase of transmitted and reflected waves.
This the error:
"Failed to find a solution.
Singular matrix.
For mesh-case 0 there are 1 void equations (empty rows in matrix) for the variable mod1.emw.S2x
at coordinates: (0,0,0), ...
and similarly for the degrees of freedom (empty columns in matrix)
Returned solution has not converged."
I appreciate if somebody can help me. I attached my file either in case if you would like to look at that and let me know what is wrong with my simulation.