根据应用了垂直空时分层(V-BLAST)结构的3种多载波CDMA系统——BL蟾TMC-CDMA系统、BLASTMC—DS—CDMA系统、BLASTMT-CDMA系统的发射信号、信道模型和接收信号,给出该3种系统的误码率公式。基于对这3种系统的误码率公式分析,比较了在带宽效率相同的条件下这3种BLAST多载波CDMA系统的误码率性能。数值结果表明:在信噪比较高的情况下,BLASTMC—CDMA系统有更好的误码率性能;在低信噪比情况下,BLASTMT-CDMA系统的误码率性能更好;BLASTMC—DS-CDMA系统的误码率性能相对较差。
The bit error rate (BER) expressions of the three multi-cartier CDMA systems which apply the Vertical Bell Laboratories Layered Space-Time (V-BLAST) technique, named V-BLAST MC CDMA, V-BLAST MC-DS-CDMA and VBLAST MT-CDMA, are given according to their transmitted signals, channel models and received signals. The BER perfonnance of the three systems under the same spectral efficiency is compared based on the analyses of the three BER formulae. The numerical results show that the V-BLAST MC-CDMA system performs best at the higher signal-to-noise ratio (SNR), the V-BLAST MT-CDMA system performs best at the lower SNR, and generally, the V-BLAST MC-DS-CDMA system performs worst compared with the other two systems.