下行MIMO传输中基于协同的干扰处理技术研究

发布时间：2018-01-21 22:47

本文关键词： 波束成形功率控制基站分簇有限基站协作干扰协同　出处：《北京邮电大学》2014年博士论文　论文类型：学位论文

【摘要】：多元化移动便携设备的普及、物联网的高速建设、移动互联网的多媒体应用以及移动宽带接入的发展共同引爆了无线网络中的“数据洪峰”；因此,未来移动通信系统除了满足信息可靠传输这一基本要求之外,还要能提供更快的传输速率,具备更短的传输时延,覆盖更广泛的地理范围,容纳更多的接入设备。从网络架构、资源利用、分布式信号处理等领域开展以提高频谱效率为目的的研究工作迫在眉睫。无线网络的发展趋势使干扰成为限制其性能的关键因素,基站协作被认为是解决该问题的有效途径之一,研究表明该技术能有效提升小区边缘用户通信质量,提高频谱效率,改善网络覆盖质量。因此,开展基于基站协作的干扰处理技术具有较高的理论价值和广泛的应用前景。本文从资源分配和网络架构角度出发,研究了多天线基站有限协作网络下行链路中的干扰处理技术,利用波束成形、功率控制和基站分簇以主动自适应方式进行干扰协同,增强了通信链路质量,提高了网络的鲁棒性和公平性。本文主要研究内容和成果包括以下四个方面：第一,研究了基于信漏噪比最大化准则设计波束向量算法中有效管理泄漏功率的问题,提出了一种提高用户公平性的加权泄漏功率波束成形算法,并设计了相应的功率控制策略。典型的信漏噪比最大化方法设计波束向量时,存在泄漏功率非公平性分布问题,该问题表现为泄漏功率对信道质量较差用户施加相对更强的破坏。首先,所提方案将携带用户信道质量信息的权重系数引入到信漏噪比优化目标中,达到泄漏功率在多个用户间动态“平衡式”分布目的,解决了典型算法中存在的公平性问题。其次,波束向量设计考虑了信道信息非理想特性相关参数,提高了网络的鲁棒性能。最后,功率控制算法利用加权信漏噪比信息完成动态功率分配,提高了系统可靠性。第二,在基站协作回传链路及信令开销受限条件下,研究了基于本地局部信道信息进行分布式波束成形设计和功率控制的问题。首先,建立基站功率约束下的网络和容量最大化的数学模型；其次,利用离散化方法将功率优化空间简化,降低计算复杂度；再次,利用本地局部信道信息设计相应的波束成形向量并根据贪婪准则设计功率分配算法；最后,分析了算法复杂度及部署方法。仿真结果表明,该方案在保证用户公平性条件下,以较低的计算复杂度获得了较高的频谱效率,为解决基于波束成形与功率控制的干扰处理问题提供了一种可行方案。第三,研究了基站有限协作网络中基站分簇问题,提出一种基于连接图及启发式效用函数的动态基站分簇方案。首先,建立基于基站分簇和基站功率受限条件下的和容量最大化问题；然后,利用基站协作关系映射产生的连接图,简化基站分簇搜索空间；其次,提出一种基于统计干扰信道增益和的效用函数来衡量连接图中边的对应权重；最后,依据连接图提供的搜索路径,利用启发式效用函数快速动态地建立基站分簇。仿真结果表明,所提方案充分利用了基站协作提供的宏分集增益,以较低的计算复杂度接近了最优方案的性能,并具备了对抗信道信息错误的鲁棒性能。第四,研究基于动态基站分簇和波束成形进行联合干扰处理的问题,提出了基于泄漏功率和统一设计基站分簇算法与波束成形的干扰协同框架。首先,建立了泄漏信道信息概念,以基站簇为整体分析其中泄漏功率和的数学表达式意义；然后,依据泄漏功率和最大化准则以动态方式形成基站分簇,将网络中的干扰更多地转变为簇内干扰；其次,利用基于信漏噪比最大化算法的簇内协作波束成形对泄漏干扰进行抑制。仿真结果表明,所提方案提高了用户平均容量及边缘用户容量,实现了计算复杂度及性能增益折中,具备了接近最优方案的中断概率性能。
[Abstract]:The popularity of diversified mobile devices, high-speed construction of things, mobile Internet and mobile broadband multimedia application development jointly detonated in a wireless network; therefore, the "data" flood of future mobile communication systems in addition to meet the basic requirements of reliable information transmission, but also can provide a faster transfer rate, with transmission delay a shorter, broader coverage of the geographical scope, to accommodate more access equipment. Using the resources from the network architecture, distributed signal processing and other areas to improve the spectral efficiency for the imminent research work purpose.
The development trend of the wireless network interference has become a key factor that limits the performance of base station cooperation, is considered to be one of the effective ways to solve this problem, research shows that this technology can effectively improve the communication quality of the cell edge users, improve spectrum efficiency, improve the quality of network coverage. Therefore, to carry out the theoretical value of interference processing technology based on base station cooperation with high and broad application prospect.
This article from the perspective of resource allocation and network architecture, the processing techniques of multi antenna base station interference limited cooperation network in the downlink, using beam forming, power control and base station cluster to active adaptive interference coordination, enhance the communication link quality, improve the network robustness and fairness. The main contents of this paper and the results include the following four aspects:
First, the research on SLNR effective management criterion of maximizing beamforming vector algorithm in leakage power based on the problems, put forward a improved weighted fairness leakage power beamforming algorithm, and designed the corresponding power control strategy. The typical SLNR maximum design method of beam vector, there the problem of non leakage power distribution fairness, the problem is the leakage power applied relatively greater damage to the poor channel quality of users. First of all, the proposed scheme will carry the weight coefficient of the user channel quality information into SLNR optimization targets, achieve the leakage power among multiple users "dynamic balance" distribution to solve the problems, the fairness of the typical algorithm. Secondly, vector beam design considering the channel information of non ideal characteristics parameters, improve the robust performance of the network. Finally, The power control algorithm uses the information of the weighted signal to complete the dynamic power allocation and improves the reliability of the system.
Second, the cooperative base station backhaul link and signaling overhead under limited conditions, studied the distributed beam forming design of local channel information and power control based on the problems. First, establish the mathematical model of base station power constraints and network capacity maximization; secondly, using the discrete method of power optimization space is simplified, reduce computational complexity again, the use of degree; local channel information design corresponding beamforming vector and algorithm based on greedy criterion design of power distribution; finally, analysis of the complexity of the algorithm and the deployment method. The simulation results show that this scheme can ensure user fairness conditions, with low computational complexity has higher spectrum efficiency, for to solve the beamforming provides a feasible scheme to deal with the problems with interference based on power control.
Third, the base station base station Limited cooperative network clustering problems, this paper proposed a dynamic base station connection graph and heuristic utility function based clustering scheme. First, the establishment of base station cluster and base station power constraints and capacity maximization problem based on; then, using the connection graph generated base station cooperative relation mapping, simplified base station cluster search space; secondly, put forward a statistical interference utility function based on channel gain and to measure the weight of edges connecting the corresponding; finally, according to the search path connection diagram provided by heuristic effect, fast dynamic function to establish a base station cluster. The simulation results show that the proposed scheme makes full use of macros the base station cooperative diversity gain, with low computational complexity is close to the performance of the optimal solutions, and have robustness against channel errors.
Fourth, study on dynamic base station clustering and beamforming combined interference processing based on the problems, puts forward the interference leakage power and unified design base station clustering algorithm and beamforming based on collaborative framework. First, establish the leakage channel information to base station for the overall concept, cluster analysis of mathematical expressions and the significance of the leakage power; then, based on the leakage power and the maximum criterion in a dynamic way to form the base station cluster, the interference in the network become more interference in the cluster; secondly, using SLNR maximization algorithm in cluster cooperative beamforming to suppress leakage based on interference. The simulation results show that the proposed scheme improves the average user capacity and the edge user capacity, the computational complexity and performance gain compromise, with the outage performance close to the optimal solution.

【学位授予单位】：北京邮电大学
【学位级别】：博士
【学位授予年份】：2014
【分类号】：TN919.3

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