GFSK modulated data demodulation settings (Experiment with MAVLink )


The flow graph I used to demodulate the GFSK modulated recorded MAVLink signals is as follows:



The parameters used for FIR filter, low pass filter : 
reference

The value for "fsk_deviation_hz" variable was taken from the documentation of the radio module.

Here is a screen shot of baudline view of signals with the raw parameter settings I used. No of channels are two, since hackRF logs I and Q data. However here, I have disabled one channel out of the two in the waveform to get the pattern.






HackRF data input to baudline: 
reference

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