协同分集(cooperative diversity)技术通过为网络中某些单天线用户寻找若干个用户作为“伙伴”,并共享彼此禾线,形成虚拟的多天线阵列,来实现多天线分集,结合分布式空时分组编码(Distributed Space Time Block Code,DSFBC),可以有效地提高系统性能.多载波码分多址(Multi—Carrier Code Division Multiple Access,MC—CDMA)技术将数据调制到各个子载波上发送,可以有效地抵抗信道频率选择性衰落的影响.本文提出了无线网络中频率选择性衰落信道环境下的一种基于分布式空时分组码和MC—CDMA的协同发射分集方案,建立了协同用户间的误码表示模型,基于该模型推导了协同分集方案误码性能的理论表达式,并分析了协同用户间的平均解码差错概率对系统方案误码性能的影响,同时给出了仿真结果.结果表明,DSTBC—MC—CDMA相对于未协同的MC—CDMA系统获得了明显的性能增益,同时仿真也较好地验证了理论结果.
A novel system based on cooperative distributed space-time block code and multi-carrier code division multiple access (DSTBC-MC-CDMA) is proposed which works well on multiple single-antenna users wireless networks in frequency selective fading channel. And an analytical model to describe the symbol decoding error between interusers is established, based on the model, a theoretical bit error rate (BER) perfomaance expression of the system has been derived. Then simulation is complimented to versify the analytic result above,and the simulation also shows that the BER performance of DSTBC-MC-CDMA outgoes noncooperative MC-CDMA with distinctive gains. Furthermore, the simulation results verify the validity of theoretical results.