论文标题
关于降低上行链路稀疏代码多访问空间调制的复杂性
On the Complexity Reduction of Uplink Sparse Code Multiple Access for Spatial Modulation
论文作者
论文摘要
最近已提出了稀疏代码多访问（SCMA）辅助的多用户空间调制（SM），以提供上行链路高光谱效率传输。传递算法（MPA）的消息用于检测具有高复杂性的传输信号。本文首次提出了三种低复杂性算法。第一种算法称为连续的用户检测（SUD），而第二算法是SUD的修改版本，即修改后的SUD（MSUD）。然后，首次构建了SM-SCMA的树搜索。基于该树搜索，为SM-SCMA提出了Sphere解码器（SD）的另一个变体，称为固定复杂性SD（FCSD）。 SUD为解码复杂性提供了一个基准，但以比特率率（BER）性能为代价。此外，MSUD稍微提高了SUD的复杂性，并显着改善了BER性能。最后，与MPA解码器相比，FCSD提供了一个接近最佳的BER，其复杂性大大降低，还支持并行硬件实现。所提出的算法为基于系统设计需求的实际实施提供了灵活的设计选择。为提出的算法提供了BER的复杂性分析和蒙特卡洛模拟。
Multi-user spatial modulation (SM) assisted by sparse code multiple access (SCMA) has been recently proposed to provide uplink high spectral efficiency transmission. The message passing algorithm (MPA) is employed to detect the transmitted signals, which suffers from high complexity. This paper proposes three low-complexity algorithms for the first time to the SM-SCMA. The first algorithm is referred to as successive user detection (SUD), while the second algorithm is the modified version of SUD, namely modified SUD (MSUD). Then, for the first time, the tree-search of the SM-SCMA is constructed. Based on that tree-search, another variant of the sphere decoder (SD) is proposed for the SM-SCMA, referred to as fixed-complexity SD (FCSD). SUD provides a benchmark for decoding complexity at the expense of bit-error-rate (BER) performance. Further, MSUD slightly increases the complexity of SUD with a significant improvement in BER performance. Finally, FCSD provides a near-optimum BER with a considerable reduction of the complexity compared to the MPA decoder and also supports parallel hardware implementation. The proposed algorithms provide flexible design choices for practical implementation based on system design demands. The complexity analysis and Monte-Carlo simulations of the BER are provided for the proposed algorithms.
