多天线中继系统的性能研究

发布时间：2018-05-21 03:28

本文选题：天线相关 + 信道估计误差　；参考：《西安电子科技大学》2014年博士论文

【摘要】：协作中继技术因其可以显著提高网络的覆盖范围、增强无线通信的可靠性而成为无线通信领域最为广泛关注的热点。为进一步提高系统容量,对协作中继系统采用多天线技术成为未来移动通信中的关键技术。如何分析和度量不同多天线中继传输系统的理论性能,是多天线中继网络相关研究的基础问题。本文从实际通信场景下多天线中继系统模型出发,分别研究了天线的空间相关性、信道估计误差、信息反馈时延和共信道干扰对单向前向放大(Amplify-and-Forward:AF)中继网络以及双向AF中继网络的系统性能的影响规律。本文的主要贡献概括如下：1.针对天线相关性,研究了基于天线选择／机会调度策略的双向前向放大中继系统(Two-way Amplify-and-Forward Relay Network:TWRN-AF)性能的影响。仅考虑基站配置天线存在空间相关的情况,K个单天线用户通过单天线中继节点与基站进行双向通信。在瑞利衰落信道条件下,推导了该系统的中断概率以及系统总容量的下界闭合表达式。在此基础上,为了更直观地理解用户数K以及空间相关系数ρ与系统性能之间的关系,进一步分析了在不同信道状态特性下,用户数K足够大时,系统总容量的渐进表达式。通过理论分析和仿真结果表明系统性能依赖于空间相关度以及系统的用户数量K。特别地,我们还分析了非对称信道特性下,中继节点的位置对系统性能的影响。2.针对信道估计误差和信息反馈时延,研究了基于波束成形技术(Beamforming)的单向多输入多输出前向放大中继网络(One-way Multiple-input Multiple-output AF Relay Networks:OWRN MIMO AF)的中断概率以及误比特率。推导了该系统的中断概率和误比特率的闭合表达式,为了获得更多直接的结果,还给出了中断概率和误比特率的渐进近似公式,分析了系统的分集增益以及编码增益与信道估计误差参数和反馈时延相关系数之间的关系。通过理论推导分析信道估计误差参数和反馈时延相关系数对系统的影响机制,并证明了多天线技术的采用可以获得更多的性能增益。但是由于信道估计误差和反馈时延的存在,使得系统性能会受到很大幅度的恶化。即使在源端S和目的端D处配置多根天线,系统的分集增益也不会有所改进,依然为0。最后,通过理论推导和仿真结果深入分析了两种不同信道估计参数模型下系统性能的优劣。仿真实验验证了理论分析结果的正确性。3.针对共信道干扰(Multiple Co-channel Interferers:CCI)和非理想信道状态信息(Imperfect Channel State Information:Imperfect CSI)存在的情况,研究了基于传输天线选择/最大比合并(Transmit Antenna Selec-tion/Receiver Maximal-ratio Combining)的单向MIMO AF中继网络的中断性能。考虑各个节点都配置多根天线并且中继节点和目的端存在多个干扰的通信场景,推导了系统端到端信干比(Signal to Interference Ratio:SIR)表达式,在此基础上,给出了系统中断概率的闭合下界以及渐进表达式,并且深入分析了不完美CSI存在的情况和不完美CSI不存在的情况下,基于多个共信道干扰的单向MIMO AF系统的分集增益以及编码增益。理论推导发现,共信道干扰恶化系统的编码增益但不影响系统的分集增益,在仅有共信道干扰存在的情况下,系统仍然可以获得满增益。但是当不完美CSI与CCI同时存在的情况下,系统分集增益将减少,系统性能急速下降。最后,通过仿真结果验证了理论分析的正确性以及比较分析了信道估计误差和反馈系数对系统性能的影响规律。
[Abstract]:Cooperative relay technology has become the most widespread concern in the field of wireless communication because it can significantly improve the coverage of the network and enhance the reliability of wireless communication. In order to further improve the system capacity, it is the key technology in the future mobile communication to adopt multi antenna technology to the cooperative relay system. How to analyze and measure different days for different days The theoretical performance of line relay transmission system is the basic problem in the research of multi antenna relay network. In this paper, the spatial correlation, channel estimation error, information feedback delay and common channel interference to one direction forward amplification (Amplify-and-Forward:AF) relay are respectively studied from the multi antenna relay system model under the actual communication scene. The main contributions of the network and the system performance of the bidirectional AF relay network are summarized as follows: 1. for the antenna correlation, the influence of the Two-way Amplify-and-Forward Relay Network: TWRN-AF based on the antenna selection / opportunity scheduling strategy is studied. Only the base station configuration antenna is considered. In the case of spatial correlation, K single antenna users communicate with the base station through a single antenna relay node. Under the Rayleigh fading channel, the interruption probability and the lower bound expression of the system total capacity are derived. On this basis, to more intuitively solve the user number K and the spatial correlation coefficient rho. The relationship between performance is further analyzed for the progressive expression of the total system capacity when the number of users K is large enough under different channel state characteristics. The theoretical analysis and simulation results show that the system performance depends on the spatial correlation and the number of users of the system, K. especially, we also analyze the relay nodes under the asymmetric channel characteristics. The effect of location on the performance of the system.2. studies the interruption probability and bit error rate of the unidirectional multiple input and multi output forward amplification relay network (One-way Multiple-input Multiple-output AF Relay Networks:OWRN MIMO AF) based on the channel estimation error and information feedback delay. In order to obtain more direct results, the asymptotic approximate formula of the interruption probability and bit error rate is given, and the relationship between the diversity gain of the system and the relationship between the coding gain and the channel estimation error parameters and the feedback delay correlation coefficient is analyzed. The channel estimation is derived and analyzed by theoretical deduction. Considering the influence mechanism of the error parameters and the feedback delay correlation coefficient on the system, it is proved that the use of multi antenna technology can gain more performance gain. But because of the existence of channel estimation error and feedback delay, the performance of the system will be greatly deteriorated. Even a number of antennas are configured at the source end S and the destination D. The diversity gain will not be improved, and still is 0.. Through the theoretical and simulation results, the system performance of the two different channel estimation parameters is deeply analyzed. The simulation experiments verify the correctness of the theoretical analysis results.3. for the common channel interference (Multiple Co-channel Interferers:CCI) and the non ideal channel shape. In the presence of Imperfect Channel State Information:Imperfect CSI, the interruption performance of a one-way MIMO AF relay network based on the transmission antenna selection / maximum ratio merger (Transmit Antenna Selec-tion/Receiver Maximal-ratio Combining) is studied. A communication scene with multiple interference is present at the end, and the end to end Signal to Interference Ratio:SIR expression is derived. On this basis, the closed lower bound and progressive expression of the system interrupt probability are given, and the existence of imperfect CSI and the absence of perfect CSI are deeply analyzed, based on multiple Co trust. The diversity gain and coding gain of a one-way MIMO AF system with channel interference are derived. The theoretical derivation shows that cochannel interference worsens the coding gain of the system but does not affect the diversity gain of the system, and the system can still gain full gain in the presence of only common channel interference. But when the imperfect CSI and CCI exist at the same time, the system points are divided. The set gain will be reduced and the system performance decreases rapidly. Finally, the correctness of the theoretical analysis is verified by the simulation results and the influence of channel estimation error and feedback coefficient on the performance of the system is compared and analyzed.
【学位授予单位】：西安电子科技大学
【学位级别】：博士
【学位授予年份】：2014
【分类号】：TN92

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