IEEE Communications Letters

A Cross-Layer Scheduling Method for Pipelined Layered Multi-Edge Type QC-LDPC Decoder With Better Conflict Resolution

Dongxu Chang, Qingqing Peng, Guanghui Wang, Guiying Yan

Published Apr 21, 2025• 2 citations

Abstract

For multi-edge type quasi-cyclic low-density parity-check (MET-QC-LDPC) codes, the presence of common variable nodes shared between rows within a single layer poses great challenges for the hardware design of the decoder. In this study, a cross-layer update scheduling method for pipelined layered MET-QC-LDPC codes is proposed to achieve improved conflict resolution. Through a probabilistic analysis, we show that by pairing layers with relatively small common degrees and performing alternating updates between the paired layers, better conflict resolution can be achieved than the layer-by-layer updating approach. Experimental results demonstrate that, at medium to low code rates, 50% to 75% of memory conflicts can be mitigated through the proposed cross-layer scheduling compared to the layer-by-layer scheduling approach, without compromising decoding performance.

DOI: 10.1109/lcomm.2025.3562626

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