The invention discloses an ultra-large point FFT (
Fast Fourier Transform) fast
processing method, which relates to the field of
digital signal fast
processing and comprises the following steps of: firstly, carrying out
zero padding operation on original sampling
signal data until the total length of a sequence meets integral multiples of M1 points; the method comprises the following steps of: performing
zero padding operation on an input super-large
point sequence, segmenting the data after the
zero padding operation, segmenting the input super-large
point sequence into L subsequences with the length of M1 points, performing FFT (
Fast Fourier Transform) calculation with the point number of M1 points on the subsequences, and performing iterative calculation by adopting a high-radix FFT
algorithm architecture; and finally, a specific
twiddle factor is multiplied by the FFT calculation result of the sub-sequence to realize
phase correction of the FFT result, the sub-FFT results after
phase correction are combined and spliced according to a specific weighting mode, the component of each frequency point is ensured to be correctly adjusted, and the FFT result of the
original data sequence is obtained. According to the method, the
algorithm complexity can be reduced, and meanwhile, the calculation efficiency of the super-large point FFT is improved.