Modulation method and device implementing a differential modulation, corresponding demodulation method and device, signal and computer software products

摘要

A method and apparatus are provided for modulating a binary source sequence including of a plurality of source words to generate modulated symbols. The method implements error-correction encoding of the plurality of source words, implementing one or more encoding modules, each implementing a separate error-correction code to generate a plurality of code words, the source words being encoded in series. The code words are interlaced to generate an interlaced sequence. The interlaced sequence is differentially modulated to generate modulated symbols. Each code word is broken down into at least one group with a number of bits equal to the base-2 logarithm of a number of states of a modulation implemented by the step of differentially modulating. The interlacing step distributes the groups such that two adjacent groups in the interlaced sequence belong to separate code words.

主权项

1. A method for modulating a source binary sequence formed by a plurality of source words, delivering modulated symbols, wherein the method comprises:
error correction encoding said plurality of source words, implementing one or more encoding modules, each implementing a distinct error correction code, delivering a plurality of code words, said source words being encoded successively; interlacing said code words, delivering an interlaced sequence; and differentially modulating said interlaced sequence, delivering modulated symbols, wherein each code word is split into at least one group presenting a number of adjacent bits greater than one and equal to the base-2 logarithm of a number of states of a modulation implemented by said step of differentially modulating, and wherein said interlacing step distributes the groups in said interlaced sequence so that two adjacent groups in said interlaced sequence belong to distinct code words that were encoded successively with respect to one another.