Hello, I was able to create a flowgraph in GRC to demodulate a signal (low-frequency battery telegram of wireless microphones). Now I started to port the generated code from Python to C++. I had to realize that some blocks are Python-only, like the FM Demodulator. I was able to rebuild the FM Demodulator in C++, for one exception: The FM demodulator uses optfir, which is implemented in Python, so it cannot be used in C++. So I replaced it with firdes (I noticed the parameter difference in transition band end and transition band width). Another thing is that the Frequency-Xlating-Filter uses a complex lowpass, but in C++ I could only find a complex band-pass, so I used a band-pass with lower frequency 0, is that the same?
Also it works, the signal is a lot noisier and the result cannot be decoded in many cases. I think the reason are the different filters. Could that be the reason? As I understood, both optfir and firdes create just a bunch of numbers and that´s it. As my program is not going change the filter parameters they could be hardcoded in my program, right? Best regards Stefan _______________________________________________ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org https://lists.gnu.org/mailman/listinfo/discuss-gnuradio
