广义多天线系统中的空间调制技术研究

发布时间：2018-02-26 23:10

本文关键词： 协作通信多输入多输出空间调制空移键控发射分集　出处：《天津大学》2014年博士论文　论文类型：学位论文

【摘要】：近年来，多天线和协作通信技术的研究引起了学术界和产业界的极大关注。多天线技术，即多输入多输出（MIMO）传输技术，能为发射机和/或接收机端配置多根天线的通信系统提供空间复用增益和/或空间分集增益。在某些环境中，移动设备受到体积、复杂度以及功耗因素的制约，无法配置多根天线。此时，协作传输技术可以利用一组单天线终端通过彼此共享天线和其他资源的方式提供分集增益。因此，协作通信系统也可视为广义的MIMO系统。空间调制（SM）和空移键控（SSK）是面向MIMO无线系统的低复杂度空间复用技术。SM/SSK技术的典型特征是将多天线构成空间域，以此作为传输信息的新资源。与单天线系统相比，SM/SSK能够提供更高的频谱效率和更强的鲁棒性。此外，SM/SSK可以避免传统MIMO技术中存在的信道间干扰（ICI）和天线同步（IAS）问题，因而具有更低的系统复杂度。本论文主要研究SM/SSK思想在MIMO和协作通信系统中的应用，设计了面向MIMO系统的空间星座自适应映射机制，提出了面向多中继网络的SSK协作传输策略。具体研究内容归纳如下。提出了面向广义空移键控（GSSK）系统的自适应空域优化技术。GSSK拓展了SSK定义的空间域概念，构成空间星座的不再是各发射天线，，而是多根被激活天线的组合。与SSK技术相比，GSSK具有更高的频谱效率。遗憾的是，SSK和GSSK技术都无法获得发射分集。并且，在GSSK的空间星座中普遍存在不携带任何信息的冗余星座点。基于上述观察，本论文提出了一种新颖的自适应映射GSSK（AM-GSSK）技术。该技术根据信道状态信息（CSI）对包含冗余的空间星座进行优化筛选，并由此降低系统的误码率（SER）。为选取最优的空间星座点，分别提出了空间域全局优化算法和局部优化算法。理论分析表明，AM-GSSK系统能够获得发射分集。提出了面向广义空间调制系统（GSM）的信号－空间域联合优化技术。在GSM系统中，信息比特被分别映射到了信号星座和空间星座。为此，本论文提出了联合优化信号星座和空间星座的自适应联合映射GSM（AJM-GSM）技术。分别给出了全局优化算法和局部优化算法。仿真结果表明，AJM-GSM技术能明显降低GSM系统的SER。本论文将SM/SSK的思想拓展应用于协作通信系统，提出了面向多中继协作网络的协作空移键控（CSSK）传输策略。在CSSK系统中，源节点发送的信息在中继转发阶段映射到了由多个中继节点构成的分布式空间域，并通过空间域传输至目的节点。依据中继节点工作方式的不同，本论文提出了两种不同的CSSK传输模式：解调转发CSSK（DmF-CSSK）模式和解码转发CSSK（DF-CSSK）模式。分别给出了两种不同模式的最优检测算法。此外，针对DF-CSSK模式提出了一种简化的折线近似检测算法。通过理论分析给出了DF-CSSK系统所能获得的分集阶数。最后，进一步通过仿真验证了CSSK系统的性能。理论分析与仿真结果表明，CSSK作为一种面向多中继的低复杂度协作传输技术具有独特的实用优势。
[Abstract]:In recent years, research on multiple antenna and cooperative communication technology has aroused great concern in academia and industry. The multi antenna technology, namely multiple input multiple output (MIMO) transmission technology, communication system for the transmitter and / or receiver with multiple antennas provide spatial multiplexing gain and / or spatial diversity gain in some. In the environment of mobile devices, by volume, complex control system and power factor, unable to configure multiple antennas. The cooperative transmission technology can provide diversity gain by sharing their antennas and other resources in the way of using a set of single antenna terminals. Therefore, cooperative communication system can be regarded as a generalized MIMO system.
Spatial modulation (SM) and space shift keying (SSK) is a typical feature for MIMO wireless system with low complexity of spatial multiplexing.SM/SSK technology is multi antenna composed of spatial domain, as a new resource to transmit information. Compared with the single antenna system, the robustness of SM/SSK can provide higher spectrum efficiency and stronger. In addition, SM/SSK can avoid channel in the traditional MIMO technology interference (ICI) and antenna synchronization (IAS), so the system has lower complexity.
This paper mainly studies the application of SM/SSK in MIMO and cooperative communication system, designs the adaptive mapping mechanism for space Constellation oriented to MIMO system, and proposes a SSK cooperative transmission strategy for multiple relay networks. The specific research contents are summarized below.
Put forward based on the generalized space shift keying (GSSK) system adaptive spatial optimization technology of.GSSK extends the concept of spatial domain defined by SSK, which is no longer a constellation of each transmitting antenna, a plurality of combination but activated antenna. Compared with SSK, GSSK has higher spectrum efficiency. Unfortunately, SSK and GSSK Technology can obtain transmit diversity and redundancy of the constellation points do not carry any information in the common space constellation GSSK. Based on the above observation, this paper proposes a novel adaptive mapping GSSK (AM-GSSK) technology. The technology according to the channel state information (CSI) was adopted to optimize the selection of redundant space constellation, and thus reduce the bit error rate (SER). In order to select the optimal spatial constellation points, respectively put forward space domain global optimization algorithm and local optimization algorithm. Theoretical analysis shows that the AM-GSSK system can achieve Emission diversity.
Put forward based on the generalized spatial modulation system (GSM) combined with optimization technique of signal space domain. In GSM system, the information bits are mapped to the constellation constellation and space. Therefore, this thesis proposes an adaptive joint optimization of signal constellation and constellation mapping combined with GSM (AJM-GSM) technology are presented. The global optimization algorithm and local optimization algorithm. The simulation results show that AJM-GSM technology can significantly reduce the GSM system SER.
This paper extend the concept of SM/SSK applied in cooperative communication system, and proposes a collaborative space oriented multi relay cooperative network shift keying (CSSK) transmission strategy. In the CSSK system, the source node sends the information in the relay mapping stage to distributed spatial domain composed of multiple relay nodes, and through space the domain is transmitted to the destination node. Based on the relay node in the different ways of working, this paper presents two different transmission modes: CSSK CSSK (DmF-CSSK) demodulation forwarding mode and decode and forward CSSK (DF-CSSK) model. The optimal mode of two different detection algorithms are presented. In addition, according to the DF-CSSK detection algorithm is proposed a simplified approximate polygon. The diversity order can be obtained in DF-CSSK system is given through theoretical analysis. Finally, further verify the performance of CSSK system by simulation. Theoretical analysis and simulation results show that C SSK has a unique practical advantage as a low complexity cooperative transmission technology for multiple relays.

【学位授予单位】：天津大学
【学位级别】：博士
【学位授予年份】：2014
【分类号】：TN820;TN761

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