STORAGE-FREE METHOD AND ARCHITECTURE FOR COMPUTING FFT ROTATIONS

摘要

A storage-free method and architecture for computing FFT rotations makes it possible to compute the FFT decomposed according to the Cooley-Tukey algorithm without using stored data. The rotation angles of the FFT steps are generated by a single counter (1) and a circuit comprising adders and logic gates, eliminating the need to store data related to rotation angles. Rotations are computed using a modified CORDIC algorithm which makes it possible to simplify the micro-rotation computing blocks. Moreover, a system is disclosed which uses only two subtracters to compensate for the typical scaling of the CORDIC algorithm.