【作者】 赵美玲；

【导师】 王华奎；

【作者基本信息】 太原理工大学 ， 通信与信息系统， 2007， 硕士

【摘要】 第三代移动通信系统中，多用户检测和阵列天线技术是关键技术，是通信信号处理的研究热点。多址干扰和码间串扰是两个主要的干扰源，严重影响了系统容量和性能，想要真正的消除干扰，大幅度提高系统容量，必须通过第三代移动通信的关键技术来解决。从目前国内外研究成果看，提出算法复杂度低、性能优良的空时多用户检测算法是研究的主攻方向。因此，在对智能天线理论和多用户检测原理深入分析的基础上，本文提出了一种在码分多址移动通信系统中，将智能天线与多用户检测相结合的空时检测方案，本文主要工作概括如下：1、分别对阵列天线中波束形成和多用户检测进行了分析，首先从基本概念入手介绍了阵列天线的表达方法，讨论并比较了几个常见的最优权向量准则和自适应波束形成算法；接着对多用户检测的信号模型和多用户检测算法的性能测度做了介绍，最后介绍并比较了盲多用户检测的几种算法。2、鉴于盲多用户检测技术中存在有一些局限性，把阵列天线技术和盲多用户检测结合起来进行了研究。在高斯白噪声情况下，分别提出了空时盲自适应多用户接收机以及盲空时自适应多用户接收机，前者是在已知期望用户的特征波形和波达方向角的情况下研究的，而后者是在仅已知期望用户的特征波形下进行研究的。通过MATLAB的仿真验证了两种接收机均具有良好的抑制干扰的能力。3、针对无线移动通信系统中广泛存在多径衰落效应的情况，分析了DS-CDMA接收信号本身的结构特征，根据这个特征，在匹配滤波的基础上，从能量和信号结构的角度提出了四种不同的数据选择方案，并分析了不同数据方案应用在基于GSCLMS(基于广义旁瓣相消器结构的LMS)和Kalman算法的盲空时接收机中对多址干扰与码间干扰的影响。通过仿真给出了各个算法在不同延时情况下的合理数据选择方案，并验证了给出的新的数据选择方案在降低运算量上具较好的实用价值。本文的研究结果表明：通过采用本文提出的空时信号自适应多用户检测算法和相关数据选择方案，可以有效的提高系统性能和降低计算复杂度，基本上达到了消除多址干扰和码间串扰的目的。更多还原

【Abstract】 In the 3G mobile communication system, Multi-user detection (MUD) and the smart antenna array are key technologies, and have been a hot spot in telecom research field. Multiple Access Interference and ISI are the main sources of interference and may reduce system capability and performance seriously, In order to eliminate its influence essentially and improve system performance, we must use these key technologies.In recently years, the main research work may focus on how to present a high performance, low complexity algorithm. Based on the thorough analysis of the smart antenna theory and unlit-user detection, this paper introduces a space time detection scheme of embedding the smart antenna array into multi-user detection in CDMA mobile communication system. The main works of dissertion are as follows.First: The smart antenna array and the multi-user detection are analysed basically. At the beginning part of this thesis, the expression of the antenna array conceptually , the several vector optimization rule and adaptive algorithm of beamform are discussed and compared. The signal model and the performance estimate of multiuser detection are introduced. At last, the several algorithm of blind multiuser detection are analysed and compared. Second: Think to ocalization of the blind multi-user detection, The smart antenna is combined with multi-user detection. On theGauss White Noise signal channel, two space-time receivers are proposed, respectively. One is the space-time blind adaptive multi-user detection receiver requiring the direct-of-arrical(DOA) and signature waveform of the desired, the other is the blind space-time adaptive multiuser detection receiver requiring only signature waveform of the desired user. By MATLAB simulations, it is shown that the two space-time receivers can greatly resist MAI.Third: The structure characteristic of the received DS-CDMA signal is analyzed in the presence of multi-path slow fading effect case for wirless mobile communication. According to this characteristic, four data-selected schemes based on chip-matched filter are presented from the perspective of energy and structure of signal. And the impact of the being combined these schemes and the blind space-time multi-user detection receivers based on GSCLMS and Kalman arithmetic on multiple-access interference(MAI) and inter-symbol interference(ISI) is analyzed. Through simulation, the reasonable data-selected schemes is applicable for these algorithm on differ time-lag and the new data-selected schemes can reduce operation.The research shows that the performance and the low complexity algorithm are effectively realized with adopting the adaptive multiuser detection and the data-selected schemes put forword in this paper, and can avoid MAI and ISI basically.更多还原