SCMA系统中改进的MAX-Log MPA多用户检测算法

摘要

稀疏码多址接入(SCMA)技术是一种面向5G的新型非正交多址技术,针对SCMA技术中基于对数域的MAX-Log消息传递算法(MPA)存在检测性能较差的问题,采用对资源节点消息更新公式乘以一个影响因子的方法.该影响因子可以减少原始MAX-Log MPA由于近似计算资源节点信息造成的信息丢失,从而提升MAX-Log MPA多用户检测器的检测性能.理论与仿真结果表明,改进后的MAX-Log MPA多用户检测算法既能保持原始MAX-LogMPA算法复杂度低的优点,又能获得较好的检测性能.%Sparse code multiple access(SCMA) is a novel non-orthogonal multiple access scheme to face the future 5G communication.In allusion to the problem that sparse code multiple access (SCMA) system based on a logarithm-domain MAX-Log message passing algorithm(MPA) for multiuser detection has lower detection performance,this paper adopts a method that the message updating formula of the resource node is multiplied by a factor,which can reduce the lost messages of the original MAX-Log MPA algorithm for approximate computing the updating message of resource node.The theory and simulation results show that the improved MAX-Log MPA multiuser detection algorithm can not only maintain the low complexity of the original MAX-Log MPA algorithm,but also obtains better detection performance.