现在已经成功的将复数iq信号从RTL电视棒输出，利用python来进行处理：
'对I/Q复数数据做FFT变换,numpy.fft.fft(a, n=None, axis=-1)[source]'
        'The values in the result follow so-called “standard” order: If A = fft(a, n), then A[0] contains'
        'the zero-frequency term (the mean of the signal), which is always purely real for real inputs. '
        'Then A[1:n/2] contains the positive-frequency terms, and A[n/2+1:] contains the negative-frequency '
        'terms, in order of decreasingly negative frequency. For an even number of input points, A[n/2] represents'
        ' both positive and negative Nyquist frequency, and is also purely real for real input. For an odd number '
        'of input points, A[(n-1)/2] contains the largest