Gqrx SDR is available as binary package for the Raspberry Pi 3 and other similar ARM platforms:
Drivers included: Rtlsdr, Airspy, HackRF, RFSpace, Funcube Dongle, Red Pitaya and SoapySDR (no plugins).
Running Gqrx on the Raspberry Pi is still very experimental. I strongly recommend that you start with a fresh installation of Raspbian on the MicroSD card. Once you have seen it work you can experiment with different setups and let us know how it works.
See the included readme.txt
Running Gqrx on the Raspberry Pi is still experimental and a compromise at best. You should not expect the same performance as on a high end PC.
The table below should give you an idea of what kind of performance you can expect using the default settings. Note that these tests were run using the v2.6 packages and may not be accurate for v2.9.
|Device||Raspberry Pi 2||Raspberry Pi 3|
|Rtlsdr||Works up to 1.44 Msps||Works up to 2.4 Msps|
|Airspy R2||Doesn’t work||Use 2.5 Msps and input decimation ≥ 4|
|Airspy Mini||Doesn’t work||Use 3 Msps and input decimation ≥ 8|
|HackRF||Doesn’t work (USB power?)||Works at 2 Msps|
|RFSpace SDR-IQ||Doesn’t work well (FTDI?)||Works up to 111.111 ksps|
|RFSpace Cloud-IQ||Works up to 256 ksps||Works up to 614 ksps|
|RFSpace NetSDR||Not tested (need hardware)|
|Funcube Dongle Pro||Works|
|Funcube Dongle Pro+||Works but sometimes with crackling audio|
|Red Pitaya||Not tested (need time)|
In most cases you can reduce the CPU load further by reducing the window size, sample rate, FFT rate and FFT size (try 2048 at 10-15 Hz).
If you are only interested in the FFT, set Mode to “Demod Off”. This will greatly reduce the CPU load.
Let us know how it works for you!