Due to the ability to provide superior error-correction performance, the successive cancellation list (SCL) algorithm is widely regarded as one of the most promising decoding algorithms for polar codes with short-to-moderate code lengths. However, the application of SCL decoding in low-latency communication scenarios is limited due to its sequential nature. To reduce the decoding latency, developing tailored fast and efficient list decoding algorithms of specific polar substituent codes (special nodes) is a promising solution. Recently, fast list decoding algorithms are proposed by considering special nodes with low code rates. Aiming to further speedup the SCL decoding, this paper presents fast list decoding algorithms for two types of high-rate special nodes, namely single-parity-check (SPC) nodes and sequence rate one or single-parity-check (SR1/SPC) nodes. In particular, we develop two classes of fast list decoding algorithms for these nodes, where the first class uses a sequential decoding procedure to yield decoding latency that is linear with the list size, and the second further parallelizes the decoding process by pre-determining the redundant candidate paths offline. Simulation results show that the proposed list decoding algorithms are able to achieve up to 70.7\% lower decoding latency than state-of-the-art fast SCL decoders, while exhibiting the same error-correction performance.

翻译：由于能够提供优异的纠错性能，连续消除列表(SCL)算法被广泛认为是短至中等码长极化码最有前途的译码算法之一。然而，SCL译码的串行特性限制了其在低延迟通信场景中的应用。为降低译码延迟，开发针对特定极化子码（特殊节点）的定制化快速高效列表译码算法是一个有前景的解决方案。近期已有研究针对低码率特殊节点提出了快速列表译码算法。为进一步加速SCL译码，本文针对两类高速率特殊节点——即单奇偶校验(SPC)节点和序列码率一或单奇偶校验(SR1/SPC)节点，提出了快速列表译码算法。具体而言，我们为这些节点开发了两类快速列表译码算法：第一类采用串行译码流程，其译码延迟与列表大小呈线性关系；第二类通过预先离线确定冗余候选路径，进一步并行化译码过程。仿真结果表明，所提列表译码算法在保持相同纠错性能的同时，相比现有最先进的快速SCL译码器，译码延迟最多可降低70.7%。