Patent ID: 6024485
Filing Date: 2000-02-15
Classification: H03M

Abstract:
An error correction coding/decoding method for coding and decoding Reed-Solomon codes formed of ""large symbols"" in a Galois field having more elements than the number of kinds of information symbols, said method comprising:a transmitting process wherein dummy data is set in a part in Reed-Solomon codes formed of ""large symbols"" exceeding the bit length of said information symbols, coding is performed, and after coding, only bit data remaining after the removal of this dummy data is transmitted,an adding process wherein, on the decoding side, dummy data is first added to the symbols of an information part as bit data which is insufficient to be a symbol of said Reed-Solomon codes,a transmitting process wherein, when a check symbol is transmitted, parts corresponding to the bit lengths of information symbols in said ""large symbols"" are transmitted without modification,a transmitting process wherein, when a check symbol is transmitted, parts in Reed-Solomon codes formed of ""large symbols"" exceeding the bit lengths of said information symbols are transmitted together after said exceeding parts are collected from a plurality of information symbols, grouped into bit lengths equivalent to the bit lengths of said information symbols, and transmitted,a process wherein, when decoding is performed, dummy bits are added and a syndrome calculation is performed without modification on check symbol parts corresponding to the bit lengths of information symbols in said ""large symbols"" transmitted first, and a syndrome calculation based on check bit data is performed on said data transmitted together in parts exceeding the bit lengths of said information symbols in said ""large symbols` transmitted later, anda process which performs a Galois field summation on the calculation result of said syndrome based on information obtained first and check symbols, and the calculation result of said syndrome based on data exceeding the bit lengths of said information symbols transmitted later.