An Iterative Soft-Decision Decoding Algorithm of Block Codes Using Reliability Values

신뢰도 값을 이용한 블록 부호의 반복적 연판정 복호 알고리즘

  • 심용걸 (단국대학교 전자·컴퓨터학부)
  • Published : 2004.02.01


An iterative soft-decision decoding algorithm of block codes is proposed. With careful examinations of the first hard-decision decoding result, the candidate codewords are efficiently searched for. An approach to reducing decoding complexity and lowering error probability is to select a small number of candidate codewords. With high probability, we include the codewords which are at the short distance from the received signal. The decoder then computes the distance to each of the candidate codewords and selects the codeword which is the closest. We can search for the candidate codewords which make the error patterns contain the bits with small reliability values. Also, we can reduce the cases that we select the same candidate codeword already searched for. Computer simulation results are presented for (23,12) Golay code. They show that decoding complexity is considerably reduced and the block error probability is lowered.


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