A Variable Node Design with Check Node Aware Quantization Leveraging 2-Bit LDPC Decoding

Philipp Mohr; Gerhard Bauch

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arXiv · 2211.06973

A Variable Node Design with Check Node Aware Quantization Leveraging 2-Bit LDPC Decoding

Philipp Mohr·Gerhard Bauch

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Abstract

For improving coarsely quantized decoding of LDPC codes, we propose a check node aware design of the variable node update. In contrast to previous works, we optimize the variable node to explicitly maximize the mutual information preserved in the check-to-variable instead of the variable-to-check node messages. The extended optimization leads to a significantly different solution for the compression operation at the variable node. Simulation results for regular LDPC codes confirm that the check node aware design, especially for very coarse quantization with 2- or 3-bit messages, achieves performance gains of up to 0.2 dB - without additional hardware costs. We also show that the 2-bit message resolution enables a very efficient implementation of the check node update, which requires only 2/9 of the 3-bit check node's transistor count and reduces the signal propagation delay by a factor of 4.

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Philipp Mohr, Gerhard Bauch. 2022-11-13. A Variable Node Design with Check Node Aware Quantization Leveraging 2-Bit LDPC Decoding. https://arxiv.org/abs/2211.06973

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