this post was submitted on 03 Oct 2023
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Something for I/Q recordings. But I don't know what would do it. Currently the most supported format seems to be s16be WAV, but there's different formats, bit depths and encodings. I've seen .iq, .sdriq, .sdr, .raw, .wav. Then there's different bit depths and encodings: u8, s8, s16be, s16le, f32,... Also there's different ways metadata like center frequency is stored.
what is this
God damnit. I wrote an answer and it disappeared a while after pressing reply. I am lazy to rewrite it and my eyes are sore.
Anyway, I am too dumb to actually understand I/Q samples. It stands for In-Phase and Quadrature, they are 90° out of phase from each other. That's somehow used to reconstruct a signal. It's used in different areas. For me it's useful to record raw RF signals from software defined radio (SDR).
For example, with older, less secure systems, you could record signal from someone's car keyfob, then use a Tx-capable SDR to replay it later. Ta-da! Replay attack. You unlocked someone's car.
In a better way, you could record raw signal from a satellite to later demodulate and decode it, if your computer isn't powerful enough to do it in real-time.
If you want an example, you can download DAB+ radio signal recording here: https://www.sigidwiki.com/wiki/DAB%2B and then replay it in Welle.io (available as Appimage) if it's in compatible format. I haven't tested it.