Software-Defined Radio (SDR)

With these resources, you can learn how to capture, replay, and demodulate radio signals broadcast by wireless devices, as well as craft your own arbitrary messages.

Radios:

• RTL-SDR: Cheap (~$40) receive-only radio dongle. 500KHz to 1.7GHz operating frequency. About 2.4MHz receive bandwidth.
• HackRF One: Great balance between capability and price. 1MHz to 6GHz operating frequency, can receive up to 20MHz bandwidth. Importantly, it can transmit (though only in half duplex). It’s open source, so you can find cheaper clones.
• ADALM-PLUTO a.k.a PlutoSDR: Similar to the HackRF, but supports full duplex. 325MHz to 3.8GHz operating frequency, with 20MHz receive bandwidth.

Learning Resources:

• DXZone Software Defined Radio Resources: Repository of SDR resources. Includes beginner guides.
• GNU Radio Tutorials: GNU Radio is a graphical signal processing tool with drag-and-drop processing blocks. Think of it like Cyberchef for signal processing.
• RF I/Q Captures: Prerecorded radio samples to practice creating signal processing pipelines.

Tools:

• Gqrx: Open-source SDR receiver and recorder.
• SDR Sharp: Simple proof-of-concept Windows application to get hands into signal processing techniques.
• Universal Radio Hacker (URH): Suite for wireless protocol investigation. Buggy, but valuable!
• Inspectrum: Signal inspector with useful measurement and demodulation capabilities.