Nonbinary LDPC decoding by min-sum with Adaptive Message Control

A new decoding algorithm, referred to as Min-Sum with Adaptive Message Control (AMC-MS), is proposed to reduce the decoding complexity of nonbinary LDPC codes. The proposed algorithm adaptively trims the message length of belief information to reduce the amount of arithmetic operations. Exploiting the fact that during the decoding iteration, the distribution of belief information will become more concentrated around the correct element in the case of convergence, the messages can be truncated accordingly by considering only a few entries with large likelihood. Simulation results with a GF(16) nonbinary LDPC code indicate that the proposed approach can reduce arithmetic operations by up to 65% compared with non-truncated cases. Compared with the state-of-the-art extended MS (EMS) decoding, the proposed AMC-MS algorithm can reduce the computation by up to 50%, thereby enabling low-complexity decoding of nonbinary LDPC codes.