Re: Strange FFT AUDIO

[Alberto]

Thank you very much !

To obtain a real FFT i can use Float to Complex block ?

Inviato da iPhone

Il giorno 19 apr 2021, alle ore 20:36, Kevin Reid <kpreid@switchb.org> ha scritto:

GNU Radio is designed for working with IQ / complex signals. You are seeing the symmetric spectrum that results from treating a real-valued signal as a complex one with a zero quadrature (imaginary) component. The second peak is the mirror image of the first.

It is offset on the scale to 2 kHz because you have specified a nonzero center frequency, which offsets the frequency numbers on the scale but does not change the actual data processing.