Ultra-Low-Latency LDPC Decoding Architecture using Reweighted Offset Min-Sum Algorithm

Due to an iterative nature, a low-density parity-check (LDPC) decoder is associated with a long latency, being a major bottleneck of the baseband processor in wireless communication systems. Based on the practical min-sum (MS) decoding method, in this paper, we present a cost-effective algorithm for reducing the processing latency of LDPC decoders. By checking the number of short-length cycles in the LDPC code structure, the proposed method dynamically changes the reweighting factor at the iterative operations, successfully reducing the average number of iterations. In addition, we present several optimization schemes to mitigate the hardware overheads resulting from the proposed reweighting scheme. In a 65-nm CMOS process, a prototype IEEE 802.11ay LDPC decoder optimized by the proposed schemes reduces the decoding latency by 1.7 times with negligible overheads compared with the contemporary designs.