Patent ID: 6631167
Filing Date: 2003-10-07
Classification: G06T,H04L

Abstract:
A process for transforming a stream of respective groups of 2N real input data into a stream of complex output symbols respectively formed of N complex output samples, by a processing of the interleaved type comprising:performing initial processing for a current input group comprising formulating a current initial symbol formed of N current initial complex samples ordered according to a natural order corresponding to reception of input data of the current input group; performing a Fourier transform calculation of size N delivering in an order reverse with respect to the natural order, N current auxiliary complex samples forming a current auxiliary symbol; performing subsequent processing of the current auxiliary symbol in which N current complex output samples are ordered according to the natural order, and forming a current output symbol based upon the current auxiliary samples delivered, the subsequent processing comprising sequentially storing N auxiliary samples in two separately addressable random access memories of respective size at least equal to N/2 using a first addressing sequence corresponding to a first one of the natural and reverse orders, sequentially formulating N output samples and their sequential delivery in the natural order based upon a reading of the N stored auxiliary samples using a second addressing sequence corresponding to a second one of the natural and reverse orders, the subsequent processing of the current auxiliary symbol being temporally nested with the respective subsequent processing of a preceding auxiliary symbol and of a next auxiliary symbol, and addressing of the two separately addressable random access memories being performed successively and alternately according to the first and the second addressing sequences.