Serial-parallel FFT array processor

An array architecture for computing a fast Fourier transform (FFT) with a flexible number of identical processing elements is presented. The architecture is based on the symmetry of a constant geometry FFT. It allows an easy tradeoff between the hardware complexity and the computation time. A method for constructing a high-radix FFT with simple lower-radix hardware based on successive decompositions and premultiplications has been developed. It shows that a high-radix, lengthy FFT can be efficiently implemented with simple hardware. To verify the architecture, an experimental radix-2 processing element chip has been designed and the results are discussed