Concatenated codes combining Reed-Solomon codes, LDPC codes and parity codes for encoding/decoding devices

摘要

An error correction device error corrects without increasing the circuit scale. An encoder includes: a first ECC encoder (235) which interleaves a data string into n (n ≥ 2) blocks of data strings at every m (m ≥ 2) bits, and adds the error correction code parity; a parity encoder (234) which creates a parity bit at every plurality of bits of the error correction code word, and adds the parity bit to said error correction code word; and a second ECC encoder (220), which generates a second error correction encoding, which is a linear encoding using iterative decoding. Concatenated type encoded data, where a parity bit is added to every plurality of bits, is created, so an increase of circuit scale can be prevented even if a data string is interleaved into a plurality of blocks and error correction code parity is generated. The device may be applied, for example, to a long sector type hard disk.