DECODER AND DECODING METHOD

摘要

A decoder for preventing error correction during decoding an extended Reed-Solomon code comprises a section for calculating an input data syndrome from input data calculating a corrected data syndrome from first correction data determined from the input data, an evaluation polynomial/position polynomial deriving section for outputting the coefficient of each order of an error evaluation polynomial and an error position polynomial based on the input data syndrome and the magnitude of an error, a chain search section for outputting the root of the error position polynomial, and an error correcting section for outputting error-corrected input data as first corrected data when an error exist in the input data otherwise outputting the input data as the first corrected data and outputting a restored input data as second corrected data when an error exist in the first corrected data otherwise outputting the first corrected data as the second corrected data.