5G New Radio (NR) has stringent demands on both performance and complexity for the design of low-density parity-check (LDPC) decoding algorithms and corresponding VLSI implementations. Furthermore, decoders must fully support the wide range of all 5G NR blocklengths and code rates, which is a significant challenge. In this paper, we present a high-performance and low-complexity LDPC decoder, tailor-made to fulfill the 5G requirements. First, to close the gap between belief propagation (BP) decoding and its approximations in hardware, we propose an extension of adjusted min-sum decoding, called generalized adjusted min-sum (GA-MS) decoding. This decoding algorithm flexibly truncates the incoming messages at the check node level and carefully approximates the non-linear functions of BP decoding to balance the error-rate and hardware complexity. Numerical results demonstrate that the proposed fixed-point GAMS has only a minor gap of 0.1 dB compared to floating-point BP under various scenarios of 5G standard specifications. Secondly, we present a fully reconfigurable 5G NR LDPC decoder implementation based on GA-MS decoding. Given that memory occupies a substantial portion of the decoder area, we adopt multiple data compression and approximation techniques to reduce 42.2% of the memory overhead. The corresponding 28nm FD-SOI ASIC decoder has a core area of 1.823 mm2 and operates at 895 MHz. It is compatible with all 5G NR LDPC codes and achieves a peak throughput of 24.42 Gbps and a maximum area efficiency of 13.40 Gbps/mm2 at 4 decoding iterations.

翻译：5G新无线电（NR）对低密度奇偶校验（LDPC）译码算法及其相应VLSI实现的性能与复杂度均提出了严苛要求。此外，译码器必须完全支持5G NR所有码长和码率的广泛范围，这是一项重大挑战。本文提出一种专为满足5G需求而定制的高性能低复杂度LDPC译码器。首先，为缩小置信传播（BP）译码与其硬件近似实现之间的性能差距，我们提出一种调整最小和译码的扩展方案，称为广义调整最小和（GA-MS）译码。该译码算法在校验节点层级灵活截断输入消息，并精确近似BP译码的非线性函数，以平衡误码率与硬件复杂度。数值结果表明，在5G标准规范的各种场景下，所提出的定点GA-MS算法与浮点BP相比仅存在0.1 dB的微小差距。其次，我们基于GA-MS译码提出一种全可重构的5G NR LDPC译码器实现方案。鉴于存储器占据译码器面积的显著部分，我们采用多种数据压缩与近似技术，削减了42.2%的存储开销。相应28nm FD-SOI ASIC译码器核心面积为1.823 mm²，工作频率为895 MHz。该译码器兼容所有5G NR LDPC码，在4次译码迭代下可实现24.42 Gbps的峰值吞吐量和13.40 Gbps/mm²的最大面积效率。