Unified gnuradio input/output block for a variety of SDR devices,
including FUNcube Dongle, OsmoSDR, RTL-SDR, MSi2500, SDRplay, SDR-IQ,
AirSpy, rad10, HackRF, bladeRF, USSRP/UHD, UMtrx, RedPitaya, FreeSRP,
...
