Patent ID: 6145111
Filing Date: 2000-11-07
Classification: G11B,H03M

Abstract:
A method of error-correction coding of source data elements, comprising the steps of:(a) coding the source data elements using one or more product codes having a common component code, to provide one or more primary product codewords, each of the primary product codewords consisting of a plurality of first codewords of the common component code;(b) assembling one or more first sets of codewords of the common component code, each of said first sets comprising two or more distinct first codewords forming part of a same primary product codeword;(c) codeword-mapping each of the codewords of each of the first sets to a second codeword of the common component code using a one-to-one codeword-mapping to provide one or more second sets of second codewords, each second set corresponding to a first set of codewords, codeword-mappings of each codeword of a first set including the step of:(i) re-ordering, according to a known interleaving pattern, the symbols within a codeword,the codeword-mappings being such that if all of the codewords of a first set are from a same primary product codeword, then some codeword-mappings applied to the codewords of the first set are different, and if two or more repetitions of a same codeword are included in a single first set, then the codeword-mappings applied to those repetitions are different;(d) coding each set of second codewords using a systematic code so as to generate a secondary product codeword for a product code having as component codes the common component code and the systematic code; and,(e) providing encoded output data comprising the primary product codewords and the non-systematic portion of the secondary product codewords.