METHOD AND DEVICE FOR FAST FOURIER TRANSFORM

A FFT/IFFT method, comprises converting a set of reversal-order or a set of natural-order addresses of FFT/IFFT data to a set of addresses in a radix-based numeral representation; calculating sequence numbers of a plurality of memory locations for buffering a set of data for a parallel calculation, by accumulating or subtracting all digits of the set of addresses in the radix-based numeral representation and then performing a modulo operation on the accumulation or subtraction results, wherein the radix represents a length of short DFT sequence for the parallel calculation in a FFT/IFFT calculation; storing the FFT/IFFT data simultaneously and respectively into corresponding memory locations indicated by the calculated sequence numbers; and performing FFT/IFFT calculation, comprising: performing short DFT sequence calculation; repeating the short DFT sequence calculation, until the whole FFT/IFFT calculation completes.