Two kinds of apparatus for combining N.sub.2 chirp-Z transform (CZT) modu of length N.sub.1 to perform a discrete Fourier transform (DFT) of length N.sub.1 N.sub.2. The first method uses an auxiliary parallel-input, parallel-output, DFT device of size N.sub.2 and allows the transform of size N.sub.1...http://www.google.de/patents/US3965343?utm_source=gb-gplus-sharePatent US3965343 - Modular system for performing the discrete fourier transform via the chirp-Z transform
