Rust bindings for libairspy

Prereqs

Requires libairspy at least 1.0.6 already built and installed on your system. Tests require an attached Airspy (otherwise there is not much to test!) and must be run with RUST_TEST_THREADS=1 or the threads may stomp on each other.

Outline

The basic gist is:

1. Make new Airspy object
2. Configure it using set_sample_rate, set_freq, etc
3. Create a MPSC channel for data transfer
4. Use start_rx<T> to begin transfer to your channel, specifying desired sample type with T (see below)
5. Call rx.recv() on your side to read in the data buffers
6. When your half of the channel is destroyed, the Airspy is stopped

Sample Types

Sample types are set by the T in start_rx<T>. It can be any of:

• IQ<f32>
• IQ<i16>
• Real<f32>
• Real<i16>
• Real<u16>

The type is passed to libairspy which does the conversion from the native Real<u16>. Note that Real types give you twice as many samples per time period than IQ. Also note that Real<T> is just an alias for T, and IQ<T> for Complex<T>, so all the usual maths operations are available for both types.

Example

Simple usage example:

extern crate airspy;
use airspy::{Airspy,IQ};
use std::sync::mpsc;

// Open first available Airspy and configure for floating IQ samples,
// 10Msps, 434MHz (can also set gains, AGC, RF bias etc).
let mut dev = Airspy::new().unwrap();
dev.set_sample_rate(0).unwrap();
dev.set_freq(434000000).unwrap();

// Samples are sent back to us from the C thread by an MPSC channel
let (tx, rx) = mpsc::channel();

// Begin receiving data, ask for f32 IQ samples.
// This implies that the mpsc channel will have type Vec<IQ<f32>>.
dev.start_rx::<IQ<f32>>(tx).unwrap();

// Blocking receive samples, stop after 10M. When the `rx` object goes out of
// scope and is destroyed, the `tx` detects the hangup and tells libairspy to
// stop data reception.
let mut n_samples = 0usize;
while dev.is_streaming() {
    let samples = rx.recv().unwrap();
    n_samples += samples.len();
    println!("Got {} samples so far", n_samples);
    if n_samples > 10_000_000 {
        break;
    }
}

See src/bin/rx.rs for a complete example of logging IQ data to file, or asfmrs for an example application (narrowband FM demodulation to audio output).