nRF905 demodulator/FLARM decoder

make                                            # compile everything
rtl_sdr -f 868.05m -s 1.6m -g 49.6 -p 49 - |    # tune to 868.05 MHz, set sample rate to 1.6 MHz, gain to 49.6 dB, and tuner error to 49 ppm
    ./nrf905_demod 29 |                         # demodulate nRF905 packets with 29 bytes per message
    ./flarm_decode 43.21 5.43 12                # decode FLARM packets for ground station located at latitude 43.21, longitude 5.43 and geoid height 12

References

• Controlling the Wattcher Display
• FLARM receiver for GNU Radio
• G.9959(ZWave) demodulator
• Sniffing and decoding NRF24L01+ and Bluetooth LE packets for under $30
• Using a RTLSDR dongle to validate NRF905 configuration
• Implementation of Digital Signal Processing: Some Background on GFSK Modulation
• An Arctangent Type Wideband PM/FM Demodulator with Improved Performances
• nRF905 Single chip 433/868/915MHz Transceiver Product Specification
• The Sliding DFT