导　　师： 廖桂生

学科专业： H1002

授予学位： 博士

作　　者： ;

机构地区： 西安电子科技大学

摘　　要： mimo（multiple-input multiple-output）技术充分开发空间资源，利用多根天线实现多发多收，在不需要增加频谱资源和天线发送功率的情况下，可以成倍地提高信道容量，满足未来无线通信中高速数据传输的需求。以智能天线和空时编码为代表的多天线技术是目前公认的实现上述目标的最佳选择。波束形成技术源于智能天线，增强期望用户信号功率、抑制干扰用户信号是其典型的技术优势，也是sdma（space division multiple access）能够得以实现的基础。而stbc（space time block code，空时分组码）则是实现mimo分集的重要手段，能有效对抗信道的多径衰落。从发展趋势看，两者的有效联合将可以充分发挥多天线的优势，进而实现系统性能的大幅提升。也应看到，天线选择技术是最近发展起来的一种非常有效的低成本、低复杂度的多天线分集技术，具有重要的理论和实际价值，在无线通信领域正发挥着越来越重要的作用。本论文主要针对mimo系统的发射和接收天线阵元，研究阵元优化调度方法，结合阵列信号处理，提出在不增加硬件投入情况下，经过合理天线阵元调度而提高系统性能的优化算法，并且通过理论分析与仿真实验进行验证。主要包括以下几个方面内容： 1．提出一种适用于任意发射天线数的qostbc子阵分组发射分集方案，该方案克服传统方法中性能随波达角度（doa）和角度扩展（as）变化而剧烈波动的不足。其基本思想是：将发射天线平均分组，空时编码信号经各子阵的波束形成加权后定向发射；接收机利用空时编码矩阵特点进行选择接收，将接收信号分成两组，利用分组内信号的正交性进行组间干扰抑制，由于每组都是alamouti编码，因此每组都可以获得满速率和满分集增益，将两组合并后仍可以获得满分集增益。从理论分析和计算机仿 MIMO /(Multiple-Input Multiple-Output/) technique utilizing multiple antennas to realize multiple transmissions and multiple receiving can exploit space resource adequately and can improve channel capacity without any loss in bandwidth and transmitting power. So it can meet the need of high data transmission in future wireless communications. Multi-antenna systems, such as smart antenna and space-time code, are well-known as the best choice to meet above targets. Beamforming comes from smart antenna with strengthening desired signal and suppressing inter-users interference as its typical technical superiority. It is also the base to realize SDMA /(Space Division Multiple Access/). STBC /(Space Time Block Code/) is the main method to realize MIMO diversity, and it is good at mitigating the influence of wireless multipath fading. In view of development trend, the combination of beamforming and STBC will adequately exert the advantage of multi-antenna systems and result in enhancing the system performance significantly. Antenna selection is low-cost and low-complexity alternative to capture many advantages of MIMO systems. It becomes very import for wireless communications because of its significance in theory analysis and applications. Aiming at MIMO system transmit//receive antenna elements, several scheduling elements optimal algorithms are designed and studied, and logical select antennas algorithms is proposed for low-cost and low-complexity based on array signal processing theory in this dissertation. Then these methods are verified by theoretical analysis and computer simulations. The primary contributions included in this dissertation can be summarized as follow: 1. A novel selective receiver switching scheme combined with beamforming is proposed for making arbitrary complex quasi orthogonal STBC matrix achieve full transmission as well as full diversity. An efficient selective receiver switching scheme is proposed for STBC with full code and non-orthogonal design. In the proposed scheme with the a

关 键 词： 多输入多输出 空时编码 空分复用 阵列信号处理 稳健波束形成 等增益传输 天线选择 共信道干扰

领　　域： [电子电信] [电子电信]