摘要
该文采用数值仿真的方法探讨了MIMO系统中采用低密度校验(LDPC)码作为信道编码后的系统性能,针对LDPC码的置信度传播译码算法,提出了基于因子图(Factor graph)的联合迭代检测译码最大后验概率(MAP)算法,分析比较了发射端分别采用独立编码和联合编码对系统性能的影响,仿真结果表明,LDPC码可以充分利用MIMO系统中空间分集和时间分集性能提高系统的有效分集增益,并且联合迭代检测译码算法对这两种发射端编码结构的系统性能增益有较大差别。
In this paper, the performance of the LDPC coded MIMO system scheme is evaluated through numerical simulations, and according to the belief propagation decoding algorithm of LDPC codes, a combined iterative detection/decoding MAP algorithm based on the factor-graph representation is proposed. The system performance is analyzed under two transmitter encoding structures, namely the separate encoding structure and the combined encoding structure respectively. Simulation results show that LDPC codes can increase the effective diversity gain by utilizing both the space and the time diversity effects of the MIMO system, and the combined iterative detection/decoding algorithm results in different performance gain for the two transmitter encoding structures.
出处
《电子与信息学报》
EI
CSCD
北大核心
2004年第10期1580-1586,共7页
Journal of Electronics & Information Technology
基金
国家自然科学基金(No.90104014)资助
关键词
低密度校验码
MIM0系统
因子图
Low-Density Parity-Check (LDPC) codes
Mulitple-Input Multiple-Output (MIMO) system
Factor graph
