Hi all,
I am trying to simulate the pnoise of a circuit whose output of interest is then passed through a high pass FIR filter x(n)-x(n-1)+x(n-2)-x(n-3)+x(n-4)-...-x(n-L-1) with L even number.
Because the noise I am interested in, is the one after this filtering process, I have tried to implement this filter in a verilogA model, where I had to put the ignore hidden states option, but the result is I get 0 noise at the output of such model. Is that because the noise is not retained once electrical nets are assigned to variables within the verilog model?
As an alternative, I tried to simulate L cycles of the circuit, performing one pnoise_sampled point for each of these. The idea was to then take the L output noise power spectra and sum/subtract them accordingly to the FIR operation. However this is not yielding expected results. I see the output noise spectrum is not a complex number, therefore I guess it is just showing the absolute values and this would explain why I do not see the expected cancelation of the noise within certain portion of the frequency spectrum.
Is there a way to have a meaningful sum of the output noise at different time points, like for example by accessing the actual output power spectrum with its phase information?
Are there maybe more suitable ways to simulate this? (transient noise would require me very long simulations, so would be the last option if possible
Thank you
Best regards)