Dynamic Dual-Window Decoding for SC-LDPC Codes with Wave Enhancement

Windowed decoding (WD) based on the belief propagation (BP) algorithm, which slides along a code chain with fixed computational resources, is an efficient decoding scheme for spatially-coupled low-density parity-check (SC-LDPC) codes, particularly for long-length codes. However, due to the lack of decoding waves, WD suffers from a performance degradation compared to full BP decoding. In this paper, we propose a novel decoding schedule for WD, termed dual-WD, which enhances the decoding waves by dynamically merging and splitting two decoding windows that slide in opposite directions. Moreover, a sliding-step selection method based on partial syndrome checks is introduced to reduce decoding complexity. Simulation results demonstrate that the proposed dual-WD outperforms the conventional WD schemes under identical computational complexity constraints, thereby narrowing the performance gap between WD and full BP decoding.