Coding for informed decoders

摘要

A method of selecting a generator matrix (G) for encoding information words (m) including information symbols (m₁, m₂, m_k) into codewords (c) of a code (C) provides an enhanced error correction capability if at least one information symbol (m₁, m₂, m₃) is known a priori to a decoder decoding received, possibly mutilated codewords (r). In order to design a code of which the correction power is enhanced if some information symbols are known to the decoder prior to decoding, the generator matrix (G) is selected such that the minimum Hamming distance of at least one subcode (C') of the code (C) is larger than the minimum Hamming distance of the code (C), and that a subcode generator matrix (G') of the at least one subcode (C') is derived from the generator matrix (G) of the code (C) by omitting the at least one row from the generator matrix (G) corresponding to the at least one a priori known information symbol (m₁, m₂, m₃).