Research on stopping criterion for irregular LDPC codes decoding

ABSTRACT

In this paper, an improved stopping criterion for irregular LDPC decoding is proposed. This scheme considers the decoding property of irregular LDPC codes. When the lowest degree variable nodes reach stable state, the decoder gets the final decoding result. Therefore, the improved criterion is based on the convergence of the mean magnitude of the log-likelihood ratio (LLR) information of the lowest degree variable nodes at the output of each decoding iteration. Compared with existing schemes, this scheme decreases average number of iterations (ANI) and reduces computation complexity under slight performance degradation.

REFERENCES

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INDEX TERMS

Primary Classification:
  E. Data
  E.4 CODING AND INFORMATION THEORY

General Terms:
Algorithms, Performance

Keywords:
belief propagation decoding, irregular LDPC codes, stopping criterion