Node operation reduced decoding for LDPC codes

A novel scheme combining a stopping criterion and a node deactivation mechanism is proposed in this paper to reduce the number of node operations in LDPC decoding. The proposed stopping criterion employs an adaptive threshold to remove the channel-condition dependence of the conventional parity-check based stopping criterion. The proposed node deactivation mechanism improves the accuracy of node reliability estimation. As compared to standard BP decoding, the proposed scheme can save up to 80.06% node operations for IEEE 802.16e (2304, 1152) code. It can be implemented with only minor modifications of parity check step in standard LDPC decoders. This scheme can reduce the power consumption and decoding latency of LDPC decoder with low hardware overhead.

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