How to eliminate negative frequencies from IQ signal
I managed to do this now by having a 3 step process after converting the I/Q data to complex numbers. This is far from me understanding what i'm doing, but it's eliminating negative frequencies.


I shift the the frequencies by multiplying each i/q sample with the complex output of an oscillator at frequency PI/2. The oscillator outputs a complex number with Real being sin(pi*0.5*t), and Imaginary being cos() of the same values. Then I multiply that complex number with each sample (t advances +1 with each sample).
Next step is to high-pass filter at a quarter sample rate. So if our sample rate is 192000, my high pass cutoff is at 48000.
Lastly, we shift the whole thing back by doing the same multiplication as in 1), except with PI*1.5.


The result is I/Q data that's got everything in the negative spectrum filtered out.

I read about Hilbert transforms etc etc, but got lost halfway through that. Maybe someone has an explanation of what i did or why this works? :)