一种低复杂度多输入多输出球形译码算法

A Low Complexity Soft-Output MIMO Sphere Decoding Algorithm

针对多输入多输出(MIMO)系统接收机的软输出MIMO译码问题,提出了一种低复杂度的球形译码算法.该算法基于传统的Dijkstra球形译码算法,引入查找表机制和单树更新软值(LLR)的算法,改进Dijkstra球形译码进出栈的方法,减少系统的存储开销.在不降低系统性能的前提下,有效减少接收机的复杂度.仿真结果表明,在不同调制方式下,新的球形译码算法与最大似然(ML)译码算法性能几乎相同,同时算法复杂度大为降低.

This paper proposed a novel low complexity soft output sphere decoding algorithm for multiple input multiple-output （MIMO） system. Based on the traditional Dijkstra sphere decoding algorithm, the paper uses look-up table and single tree-search to update soft value （LLR） mechanism, improving enumer ation of points and in or out of stack method in Diikstra sphere decoding, reducing the cost of storage. Without reducing the performance of the system, the proposed algorithm can reduce the complexity of the receiver efficiently. The simulation results show that the proposed sphere decoding algorithm and maxi mum likelihood（ML） decoding algorithm are almost of the same performance with different modulation mode . Meanwhile the complexity of algorithm is reduced sharply.