[Hackrf-dev] why my FFT result is mirrored?

[Jacob Chen]

I use python to handle data form hackrf_transfer.
iq = np.empty(len(tmp)//2, 'complex')
iq.real, iq.imag = tmp[::2], tmp[1::2]
iq /= (255/2)
iq -= (1 + 1j)
iq = iq - numpy.mean(iq) #dc offset
spectrum1 = numpy.fft.fft(iq) / iq.size
spectrum = numpy.fft.fftshift(spectrum1)I draw it, but I found that my  result is mirrored.
I also try gnuradio to process data form hackrf_transfer and the image on FFT sink is also mirrored‍ .
if I get gr-complex data by osmocom source, the image on FFT sink is correct.‍
what should I do to get a correct spectrum?‍
‍
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