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What data type are raw IQ signals?

Jul 27th, 22:52

k7coi

Joined: Jul 23rd, 21:53
Total Topics: 0
Total Posts: 0
I want to make a portable foxhunting device that uses a custom algorithm to estimate the actual location of the source rather than just the azimuthal heading. (I hope to base it on a Raspberry Pi 3, a cheap SDR, a GPS peripheral, a magnetic compass peripheral, and a screen.)

I'd like to do my own analysis on the raw I/Q signal, but I'll need to know how it comes out of the radio. I'm familiar with IEEE 754 data types, but I'd like to know what I'm looking at. Are these floats? ...ints? How many bits wide are they? In other words, when I look at the binary stream, what data types am I most likely seeing?

If the format is dependent on my radio, is there a way to get this information from GNU Radio Companion?

I'm interested in doing a raw analysis like this because I need to know the signal strength in an absolute sense, even when I might be getting closer or farther from the transmitter and even if the noise floor changes. I need to bypass any AGC while retaining a full dynamic range, so do this, I'll have it scan wider when it becomes overloaded by a strong signal and narrower when the signal is weak.

Thank you. 73 de K7COI

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