多中继协作通信网络信道估计和资源分配算法研究

发布时间：2018-01-09 18:14

本文关键词：多中继协作通信网络信道估计和资源分配算法研究　出处：《哈尔滨工业大学》2017年博士论文　论文类型：学位论文

【摘要】：MIMO技术由于具有扩大信道容量和提升空间分集增益等特点成为下一代移动通信网络的关键技术之一。然而,移动终端对于尺寸和重量的限制使MIMO技术难以实现。多中继协作通信系统将分布式单天线终端视为虚拟天线阵列,应用MIMO系统的关键技术有效补偿无线信道的多径效应和路径损耗造成的信号失真,达到提升通信可靠性和扩大信号传输距离的目的。为了进一步提升系统性能,本文在慢衰落信道下对于多中继协作通信网络的信道估计问题和无线资源分配问题展开深入研究。首先对协作中继系统的转发方式和分集技术原理进行了回顾。描述了协作中继系统常用的两种转发方式,简要分析了单中继协作场景下的信号处理过程。介绍了MIMO系统采用的??两种分集技术:空时编码和空频编码,为后续章节奠定理论基础。对多中继协作通信网络的信道估计问题展开研究,提出一种基于统计信道状态信息的信道估计算法。首先,介绍了多中继网络的训练序列发送方案,推导了接收训练序列表达式并对ISI和ICI进行分析,提出了数据帧接收信号的判决反馈均衡算法。以最小化多中继节点到目的节点信道频率响应估计值的均方误差为目标函数建立最优化问题,在总发射功率恒定的前提下提出一种基于节点距离信息的训练序列功率分配算法。在慢衰落信道下提出一种基于多径延迟的判决反馈信道估计算法。仿真结果表明,本文提出的的训练序列功率分配算法有效降低了信道频率响应估计值的均方误差。对比基于LS准则的判决反馈估计算法,基于多径延迟的判决反馈估计算法在提升信道估计精度的同时降低了数据帧的误比特率,使各节点获得更精确的全局CSI。对基于分布式空时编码的功率分配问题展开研究,提出一种基于注水算法的功率分配方案。将分布式GABBA码应用到多中继AF协作通信网络中,分析了源节点和中继节点信号处理过程,对目的节点的接收信号建立数学模型并推导出接收信噪比。根据分布式GABBA编码矩阵具有准正交性的特点提出一种改进的中继节点映射算法。以最小化中断概率为目标函数建立最优化问题,根据自变量可行域的特点将该问题转化为中继节点选择与功率分配的联合优化问题,提出一种基于注水算法的功率分配方案。仿真结果表明,本文提出的中继节点映射算法有效提升了分布式GABBA码的译码性能。对比其他几种功率分配算法,本文提出的功率分配方案在提升分布式GABBA码的误比特率性能的同时降低了中断概率。对基于分布式空频编码的无线资源分配问题展开了研究,提出一种基于功率分配、子载波匹配和中继节点选择的联合优化算法。首先,以最小化成对符号错误概率为优化目标推导分布式空频编码矩阵优化准则。然后,提出一种改进的转发信号功率分配方案,证明该方案使分布式空频编码达到满分集阶数,对分布式空频编码应用子载波交织算法并给出分离因子计算方法。在编码矩阵优化准则指导下,提出一种基于子载波匹配和中继节点选择的联合优化算法。仿真结果表明,本文提出的功率分配方案使分布式空频编码达到满分集阶数,子载波交织算法有效提升了分布式空频编码的外部分集积。在分布式空频编码矩阵优化准则指导下,基于子载波匹配和中继节点选择的联合优化算法使系统性能获得进一步提升。将应用场景由两跳网络扩展到多跳网络,提出一种基于分布式空频编码的中继节点选择算法。首先,分析了多路径路由协议并将每一跳的收发节点抽象为VMIMO结构,提出一种基于分布式空频编码的物理层传输方案。然后,以最小化每一跳的成对符号错误概率性能下界为目标函数建立最优化模型,在分布式空频编码矩阵优化准则指导下提出一种中继节点选择算法。仿真结果表明,本文提出的的物理层方案使每一跳的误比特率性能下界达到满分集阶数,本文提出的中继节点选择算法有效地提升了误比特率性能下界,进一步增强了多跳网络的通信可靠性。
[Abstract]:MIMO technology has the characteristics of expanding the channel capacity and enhance the space diversity gain is one of the key technologies in next generation mobile communication network. However, the mobile terminal for the size and weight limit that MIMO technology is difficult to achieve. Multi relay cooperative communication system will be distributed to end on the day of single line virtual antenna array signal caused by multipath effect and the path loss compensation key technology application of MIMO system in the wireless channel distortion, enhance communication reliability and expand the signal transmission distance. In order to further improve the system performance, this paper in the slow fading channel for channel estimation of multi relay cooperative communication network research and radio resource allocation problems. First the way forward and diversity the technical principle of cooperative relay system is reviewed. Describes two commonly used forwarding party cooperative relay system A brief analysis of the signal processing, single relay scenario process. Introduced the use of the MIMO system?? two diversity technologies: space-time encoding and space frequency encoding, lay the theoretical foundation for the following chapters. The channel of multi relay cooperative communication network estimation research problem, proposed an algorithm to estimate the channel statistics based on channel state information. Firstly, introduces the training sequence transmission scheme for multi relay network, deduces the received training sequence and the expression of ISI and ICI analysis, put forward the judgment data frame received signal feedback equalization algorithm. To minimize the multi relay node to the destination node channel frequency response mean square error estimation establish the optimization problem as the objective function, in the premise of constant total transmit power under the proposed training sequence power allocation algorithm based on node distance information. In the slow fading channel based In multipath delay decision feedback channel estimation algorithm. The simulation results show that the proposed training sequence power allocation algorithm can effectively reduce the mean square error of channel frequency response estimation. Compared with the LS criterion of the decision feedback estimation algorithm based on decision feedback, multipath delay estimation algorithm reduces the bit error rate in the data frame and lifting the accuracy of channel estimation based on each node in the global CSI. more accurate research on power allocation problem based on distributed space-time encoding, proposes a power allocation scheme based on water filling algorithm. The distributed GABBA code is applied to the multi relay cooperative AF communication network, analyzes the source node and the relay node signal processing process the received signal to the destination node to establish the mathematical model and deduce the reception SNR. According to the distributed GABBA encoding matrix has the characteristics of quasi orthogonality A relay node mapping algorithm. To minimize the outage probability based optimization problem as the objective function, according to the characteristics of the independent variables of the feasible region of the problem is transformed into a joint optimization problem of relay selection and power allocation, proposes a power allocation scheme based on water filling algorithm. The simulation results show that the proposed algorithm of relay node mapping to effectively improve the decoding performance of distributed GABBA codes. Compared to several other algorithms of power allocation, power allocation scheme is proposed in this paper to enhance the distributed GABBA code bit error rate performance and reduce the outage probability. Research on the wireless resource allocation problem based on distributed space frequency encoding, is proposed based on a joint optimization of power allocation. The algorithm of subcarrier matching and relay selection. First of all, to minimize the pairwise symbol error probability as the optimization goal of derivation of distribution Type of space frequency encoding matrix optimization criterion. Then, this paper proposes an improved forward signal power allocation scheme, prove that this scheme makes the distributed space frequency encoding to achieve full diversity order, algorithm and calculated separation factor method of distributed space frequency interleaving encoding application sub carrier. In the encoding matrix optimization principles, proposes a joint the optimization algorithm of subcarrier matching and relay selection. Based on the simulation results show that the proposed power allocation scheme, the distributed space frequency encoding to achieve full diversity order, interleaved subcarrier algorithm effectively improves the distributed space frequency encoding the outer part of integrated. In the distributed space frequency encoding matrix optimization principles, combined optimization algorithm subcarrier matching and relay selection based on the performance of the system for further improvement. The application scenario is expanded by two hop network to multi hop network, a method based on The relay node distributed space frequency encoding selection algorithm. Firstly, analysis of the multi path routing protocol and each hop transceiver node is abstracted as VMIMO structure, put forward a kind of physical layer transmission scheme based on distributed space frequency encoding. Then, in order to minimize the wrong pairs of symbols per hop error probability performance bounds as objective function the optimization model in distributed space frequency encoding matrix optimization criterion is put forward under the guidance of a relay node selection algorithm. The simulation results show that the proposed scheme of the physical layer to lower the bit error rate performance reached in order for each hop, the proposed relay selection algorithm is effective to improve the performance of the bit error rate lower bound to further enhance the reliability of communication, multi hop network.

【学位授予单位】：哈尔滨工业大学
【学位级别】：博士
【学位授予年份】：2017
【分类号】：TN915.0

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