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新空口（NR）对低密度奇偶校验（LDPC）译码算法及其相应超大规模集成电路（VLSI）实现的性能和复杂度提出了严苛要求。此外，译码器必须全面支持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差距，我们提出一种改进型最小和译码的扩展方法，称为广义修正最小和（GA-MS）译码。该算法在校验节点层面灵活截断输入消息，并精心近似BP译码中的非线性函数，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译码器与浮点BP译码器相比，性能差距极小（仅0.1 dB）。其次，我们基于GA-MS译码提出一种完全可重构的5G NR LDPC译码器实现方案。鉴于存储器占据译码器芯片面积的大部分，我们采用多种数据压缩与近似技术，将存储器开销降低42.2%。相应的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次迭代译码时峰值吞吐量达24.42 Gbps，最大面积效率为13.40 Gbps/mm²。