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arXiv · 2505.19027

High Throughput QC-LDPC Decoder With Optimized Schedule Policy in Layered Decoding

Dongxu Chang·Qingqing Peng·Guanghui Wang·Guiying Yan
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Abstract

In this study, a scheduling policy of layered decoding for quasi-cycle (QC) low-density parity-check (LDPC) codes with high throughput and good performance is designed. The influence of scheduling on the delay of the decoder's hardware implementation and on the decoding performance are considered simultaneously. Specifically, we analyze the idle time required under various scheduling sequences within a pipelined decoding architecture and formulate the problem as a traveling salesman problem (TSP) aiming at minimizing idle time. Furthermore, considering that different scheduling sequences can affect decoding performance, we refine the graph used to solve the TSP based on scheduling characteristics that promote improved decoding outcomes. Simulation results demonstrate that the identified scheduling sequence achieves a low number of hardware delays while maintaining excellent decoding performance for 5G New Radio (NR) LDPC codes.

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Dongxu Chang, Qingqing Peng, Guanghui Wang, Guiying Yan. 2025-05-25. High Throughput QC-LDPC Decoder With Optimized Schedule Policy in Layered Decoding. https://arxiv.org/abs/2505.19027

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