MIMO系统中优化比特功率分配方法的频谱效率分析

在假设只有接收端知道信道状态信息(CSI)的情况下,为了满足固定的目标链路质量,提出了一种在多输入多输出(MIMO)系统中应用的基于V-BLAST检测算法的简单优化比特功率分配方法.由于不同的检测顺序会导致不同的等效信道增益,因此分别采用了前向排序法,反向排序法和最优排序法这3种方法进行仿真研究.当设定目标误符号率(SER)为10^-5,并采用M维的QAM调制方式时,对该方法采用3种排序法进行仿真的结果表明:在发射功率限制较低时,基于反向排序法的频谱效率性能优于前向排序法,但是不如基于特征值分解(SVD)的方法;当发射功率限制高到一定程度时,结论恰好相反.

Spectral Efficiency Performance of an Optimum Bit and Power Allocation Method for MIMO Systems

Under the assumption that the channel state information (CSI) is known only to the receiver, a simplified optimum bit and power allocation method is proposed for multiple-input multiple-output (MIMO) systems that uses V-BLAST as a detection algorithm to maintain fixed target link quality.Due to different ordering in detection resulting in different equivalent gains, forward ordering, revere ordering and optimal ordering, respectively, are considered in the simulation.When M-ary QAM is used with a target symbol error ratio (SER) of 10^-5 in the proposed method, it is found that the spectral efficiency performance of the revere ordering is better than forward ordering, but worse than the singular value decomposition (SVD) based scheme.The reverse is true in case the transmit power constraint is high enough.