MC-CDMA系统采用多用户检测器的性能分析

分析了MC—CDMA系统采用多用户检测器的性能，多用户检测器采用解相关—并行干扰抵消体制。在同样的慢瑞利衰落多径信道条件下，与Hara提出的单用户检测体制进行比较，同时分析了上行和下行信道的情况。仿真结果显示在无信道估计错误时，在下行信道，单用户MMSEC检测性能较好，但在上行信道多用户检测器的性能远远好于单用户检测器。文中迈进一步仿真分析了信道估计错误对检测器的影响，发现对于较大的信道估计错误，多用户检测器比单用户检测器更敏感。结论是MMSEC只适用于下行MC—CDMA系统，而多用户检测器是上行MC—CDMA系统信道估计错误很小时的极佳方案。

The Performance Analysis of Multiuser Detectors Introduced in MC-CDMA System

This paper analyzed the performances of multiuser detector introduced in MC CDMA system. The multiuser detector scheme is decorrelating parallel interference canceling. It is compared with Hara's single user detector in the same slow fading Rayleigh multipath channel.Both uplink and downlink channels are analyzed. The simulation results show that if there is no channel estimation error, in the downlink, single user MMSEC detector is better, while in the uplink, the performance of the multiuser detector is far better. Further analyzing the effect of channel estimation error on the detectors, it is found that the multiuser detector is more sensitive to big estimation error than the single user detector. The conclusion is that single user MMSEC detector is only suitable for the downlink MC CDMA system, while the multiuser detector is a wonderful scheme for the uplink MC CDMA system at small channel estimation error.