[Hackrf-dev] How does the hackrf generate the signals?

[Luis Bernal [n0p]]

Hackrf only works with IQ signals and doesn't "understand" the signal
being transmitted or received.

The OFDM (de)modulation is done on software on the computer. The
specific implementation varies. Try looking at the wikipedia page for
OFDM, it has a few implementation examples:

https://en.wikipedia.org/wiki/Orthogonal_frequency-division_multiplexing#Implementation_using_the_FFT_algorithm