Problem in CST microwave
Hi Dear Members
I have some problem in my CST simulation. Firstly i excited with a discrete port , as i know discrete port excite wit a signal of 1 watt but I also set user defined excitation with peak at 1000, when run it gives different amplitude (v/m) at probe defined at fequency domain domain and time domain results why they are different , I want to know how CST excite will it use my defined excitation signal or its 1 watt.
2ndly in the same project when I run with 10 lines per wavelength no error but when increased it gives error hexahederal mesh aborted. Why? Does it mean results at lower lines will be erroneous. experts plz help
Thanks in advance
For the second problem:
Have you increased the mesh further? With some mesh configurations it could happen that you can't simulate. Just increase or decrease the mesh a little bit.
Perhaps you can see in the mesh view the problem.
It could be that 10 lines per wavelength are not enough. Depends on your structure.
If you are using a S-parameter discrete port, the units are sqrt(Watt). So 1000 would actually be 31.6 Watts. I can't say I've had too much experience with this because most of the time I'm not concerned with amplitudes but rather the frequency response of the model.
Depending on the computational domain size, increasing the lines per wavelength could create more mesh cells than microwave studio can handle. This error would show up when you go to mesh view also. It's hard to say what your problem is because I'm not sure how many cells you are dealing with currently. As long as you aren't already near 100M cells I would do as Flanello says and see what happens. You may also want to try changing the frequency span of the simulation or the size of the computational domain and that could also make it solveable.
Thanks for helping me in my problem. one thing more if i can be helped. Why time domain (Probe signal) results are different with that of (Probe Linear) frequency domain.I saw that difference when I used discrete port with volts 1000 and also excitation signal -2.5 peak . It seems that in time domain it takes on excitation signal strength and in frequency domain (-2.5*1000). why is that. I think frequency domain signal should be just FFT of time domain results.
I'm not sure if I completely understand your question... but here's what I think you are asking
There are 3 types of discrete ports (S-parameter, Voltage, and Current). Since you were able to specify a voltage I'm assuming that you have specified a constant voltage port which will deliver a voltage you define (1000 Volts) with a source impedance of zero ohms at all frequencies.
If an excitation waveform is user specified, you have to keep in mind that the value of 1 is the full voltage specified in the discrete port definition. In your particular case, when the waveform reaches a value of 1 the output of the port 1000 Volts, when the waveform reaches a value of 2 the output of the port is 2000 volts and so on.
It is often recommended to avoid confusion when defining a waveform is to make the peak amplitude a value of 1 and set the desired peak amplitude in the port definition.
The frequency domain signal should be a FFT of time domain results -- if it isn't, then maybe your frequency range parameter of the model isn't wide enough? That's the only thing that I can think of.... good luck
I try to simulate a photonic structure in CSt software,where the material of the structure has nonlinearity and dispersion models and I can't enter the 2 models at same time for a material. I would be appreciate to guide me .
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