相关块衰落信道下空时检测的误码性能研究  

The BER Performance Analysis of Space-Time Detection over Correlated Block Fading Channel

作　　者：邹玉龙[1] 郑宝玉[1] 赵贤敬[1] 

机构地区：[1]南京邮电大学信号处理与传输研究院,江苏南京210003

出　　处：《南京邮电大学学报（自然科学版）》2007年第5期60-67,共8页Journal of Nanjing University of Posts and Telecommunications：Natural Science Edition

基　　金：江苏省高校自然科学重大基础研究(06KJA51001)资助项目

摘　　要：对相关块衰落信道下MPSK相干空时检测以及差分空时检测的误码性能进行了理论推导和系统仿真,给出了相应封闭形式的误比特表达式。相干检测能获得很好的误码性能,但是它需要进行精确的信道估计,以获得可靠的信道衰落的幅度和相位大小。然而,差分检测不需要进行信道估计以获取信道状态信息(CSI),因此当信道衰落速度很快或系统发射天线数目较多时,差分检测变得更加切合实际。虽然差分检测的健壮性很强,但是与相干检测相比,其误码性能要差,并且在高信噪比区域存在误码平台。仿真结果表明:相干空时检测和差分空时检测都获得了明显的分集增益,在相同的星座调制和信噪比下,相干检测的误码性能要优于差分检测,同时也和理论结果相吻合。　This paper presents the theoretical derivation and system simulation of the bit error rate（BER） performance of MPSK-based coherent space-time detection and differential space-time detection over the correlated block fading channel.It provides the closed form expressions of BER for the proposed schemes.Coherent detection can obtain good BER performance,but requires reliable amplitude and phase of channel fading through the precise channel estimation.Differential detection, however,requires no channel state information,so it becomes more practical when the channel is fast-fading or the number of transmit antenna is large.Althongh differential detection is robust,its BER performance is inferior compared to coherent detection and has irreducible error floor in the high SNR region.Numerical results have shown that both coherent detection and differential detection get distinct diversity gain and performance of coherent detetetion is better than that of differential detection under the condition of the same constellation and SNR,which coincides with the theoretical results well.

关 键 词：空时分组码 相干空时检测 差分空时检测 相关块衰落信道 误码平台 

分 类 号：TN911.23[电子电信—通信与信息系统]