摘要
提出了一种频率选择性信道下使用多天线分集接收的空时分组码多载波码分多址(MC-CDMA)系统上行链路中基于遗传算法(GA)的多用户检测(MUD)。考虑了两种个体选择机制对空时分组码MC-CDMA系统的GA-MUD性能的影响。第一种个体选择机制根据不同接收天线分支代价函数的线性合并选择个体;第二种个体选择机制针对不同天线分支代价函数根据Pareto优化准则选择个体,独立利用了不同天线分支信号携带的有用信息。仿真结果表明,在相同计算复杂度下,基于Pareto优化准则的个体选择机制的误码率(BER)性能要远远优于基于代价函数线性合并的个体选择机制;在相同BER性能下,基于Pareto优化准则的个体选择机制的计算复杂度要低于基于代价函数线性合并的个体选择机制。在子载波数为16的半载系统中,当BER性能逼近单用户界时,基于Pareto优化准则个体选择机制的GA-MUD的复杂度仅相当于最优化搜索MUD复杂度的0.01。
A genetic-algorithm （GA） assisted multiuser detection （MUD） is proposed for the receive-antenna-diversity-aided and space-time block coded （STBC） multicarrier code-division multiple-access （MC-CDMA） systems in frequency-selective fading channel. Two kinds of GA-based individual-selection strategies are investigated. The first individual-selection strategy linear combines the objective functions of all antenna-branches while the second strategy applies Pareto optimality criterion for further exploitation. Simulation results showed that： with the same computation complexity,the second strategy has much better bit error rate （BER） performance than the first one; within the same BER level, the second strategy has lower computation complexity than the first one. In the half-loaded STBC MC-CMDA systems with 16 subcarriers, GA-MUD with the second strategy approaches the single user bound while keeping a complexity of 0.01 times to that of the optimal MUD.
出处
《信号处理》
CSCD
北大核心
2008年第2期204-208,共5页
Journal of Signal Processing
