Transfer function to C# filter coefficients breakthrough

I was able today to convert the loop and the VCO filter from transfer functions to filter coefficients. Took some good weeks to get here, nonetheless this is now done and the next step would be to integrate the new Costas into the Inmarsat-C demodulator. This resolved the Costas both for real numbers (audio) and for the IQ inputs for pretty much any needed frequency and sample rate.

At this point, unless something will creep out again, I have all the parts I need to create an open source SDR# Inmarsat-C decoder plugin.


and the equivalent C#:

And the coinciding results:

The coefficients are obtained by running the Matlab tf2sos() and use the output as coeffs for the IIR direct form 2 implemented by the MathNet C# library. The equations can be found at the bottom of the previous post:

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