Enhancing Proximal Decoding for LDPC Codes through Deep Unfolding

This paper introduces a deep unfolding-assisted proximal decoding for low-density parity-check (LDPC) codes. Proximal decoding method is a decoding algorithm based on the proximal gradient method. Our proposal, deep unfolding-assisted proximal (DU-Proximal) decoding, is obtained by applying deep unfolding to the proximal decoding. We especially focus on the decoding performance in multiple-input multiple-output (MIMO) channels. In numerical experiments, we compare the error correcting capability of the proposed algorithm with the minimum mean squared error (MMSE) signal detection method, the tanh signal detection method, and the MMSE jointly with belief propagation (BP) algorithm for LDPC decoding. The experimental results demonstrate that parameter optimization via DU yields significant performance gains, especially at high signal-to-noise ratio levels.