PlutoSDR GNURadio WFM stereo demodulation, and using PlutoSDR as standalone radio with customised firmware
If you have a new uboot (v0.32 firmware), you will use following command to wide banded your plutoSDR:
fw_setenv compatible ad9364
fw_setenv maxcpus
REBOOT
'maxcpus' enables dual ARM cores, by default, only one ARM core is used for saving power.
For old uboot(firmware), use the following commands:
fw_setenv attr_name compatible
fw_setenv attr_val "ad9364"
fw_setenv maxcpus
REBOOT
'gnuradio_fmstereo' contains 3 GNURadio flow charts for demod FM stereo.
stereo_wbfm_rx_1: sync mode
stereo_wbfm_rx_2: sampling mode
stereo_wbfm_rx_combine: combine two mode together.
'pluto_fm_demod_fw' contains a plutoSDR firmware for testing plutosdr standalone FM demodulation.
Using the following commands for testing:
rx_fm -f 105.6M -M wbfm -s 250k -r 48k -A std -l 0 -E deemp -g 73 | aplay -r 48000 -f S16_LE &
or:
rx_sdr -F CF32 -s 2400000 -f 105600000 -g 73 - | csdr fir_decimate_cc 10 0.05 HAMMING | csdr fmdemod_quadri_cf | csdr fractional_decimator_ff 5 | csdr deemphasis_wfm_ff 48000 50e-6 | csdr convert_f_i16 | aplay -r 48000 -f S16_LE
By Quanquan-BG3MDO 16/02/2021