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Plugin request: polar stereo demodulation

Tudor Vedeanu
 

The current sporadic-E season brought many FM stations on the OIRT FM band, some of them broadcasting stereo using polar modulation. Is anyone interested in making a SDR# plugin for demodulating those signals? I could provide some sample recordings for testing.

Brief information regarding the polar stereo modulation: https://en.wikipedia.org/wiki/FM_broadcast_band#OIRT_bandplan

Someone on this group mentioned that Gqrx already has this implemented: https://groups.io/g/airspy/message/31222

This should be the code: https://github.com/csete/gqrx/blob/b67ff6737b95f7ddcca78821e76d21142677a841/src/dsp/stereo_demod.cpp

So I'm hoping it's not that difficult to take the MPX stream and run it through a similar demodulator.

Many thanks!