Abstract Polar coding and sparse code multiple access (SCMA) technique are excellent candidates for 5G, and have a promising prospect in optical communication, the joint design of polar coded sparse code multiple access (PC-SCMA) system is important to enhance the overall system performance. In this paper, a serial joint iterative detection and decoding scheme is proposed by passing message between serial max-log message passing algorithm and soft cancellation (SCAN) algorithm, the strategy can accelerate the algorithm convergence speed by reducing the number of required iterations, decrease the computational complexity and achieve ideal bit error rate (BER) performance. In order to further improve the BER performance, a cyclic redundancy check (CRC) is added in the joint iterative process as an early stopping criterion to avoid decoding divergence caused by a low signal to noise ratio (SNR). Simulation results demonstrate that the addition of a termination mechanism can obtain an excellent performance gain compares with the conventional JIDD algorithm.

中文翻译：

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极性编码SCMA系统联合迭代检测解码优化方案

摘要 极性编码和稀疏码多址（SCMA）技术是 5G 的优秀候选技术，在光通信领域具有广阔的前景，极性编码稀疏码多址（PC-SCMA）系统的联合设计对于提升整个系统具有重要意义。表现。本文提出了一种串行最大对数消息传递算法和软消除(SCAN)算法之间传递消息的串行联合迭代检测解码方案，该策略可以通过减少所需迭代次数来加快算法收敛速度，减少计算复杂度并实现理想的误码率 (BER) 性能。为了进一步提高BER性能，在联合迭代过程中加入循环冗余校验（CRC）作为提前停止准则，以避免低信噪比（SNR）引起的解码发散。仿真结果表明，与传统的 JIDD 算法相比，加入终止机制可以获得优异的性能增益。