Coding and decoding methods and devices and equipment using them

摘要

The coding device according to the invention supplies code words, the symbols of which are capable of modulating a physical quantity on a transmission channel making use of symbols of a first alphabet. The decoding of these code words uses symbols of a second alphabet containing the first alphabet, the cardinal of the second alphabet being strictly greater than that of the first alphabet and not being an integer power of the cardinal of the first alphabet. The coding device has : an input of "primary" symbols belonging to the first alphabet; - processing means which : determine redundant symbols capable of allowing decoding of the code words formed from primary symbols and redundant symbols, by a decoder working on the second alphabet; solve a system of equations expressing the constraints to be met so that the said redundant symbols are in the first alphabet. an output of the symbols of the code words.