【作者】 孙绍刚；

【导师】 焦李成；

【作者基本信息】 西安电子科技大学 ， 电路与系统， 2002， 硕士

【摘要】 随着全球通信业务的迅速发展，作为未来个人通信主要手段的无线移动通信技术引起了人们极大的关注。CDMA系统是干扰受限系统，接收机的设计是一个很重要的问题。如何消除信道干扰(CCI)、多址干扰(MAI)与多径衰落的影响成为人们在提高无线移动通信系统性能的主要因素。多用户检测和智能天线就是两种受到人们极大重视的关键技术。本文主要研究了无线移动系统中等效特征波形、多径衰落信息的估计方法以及阵列天线在系统中的应用。主要工作分为两部分： 首先我们提出了两种高斯慢衰落信道环境中信道参数的估计方法。将信号子空间方法和独立分量分析方法分别应用到信道参数估计中。仿真结果证明了两种方法的良好性能。 第二部分将阵列天线用在接收机中以改善系统性能。通过对传空时统接收机的分析，在降低系统复杂性的基础上提出一种简化的空时接收机；并利用DS-CDMA系统采用的扩频波形的特性，提出一种适合于直扩系统的数字波束形成算法。改善了接收机的检测性能。 本文的工作得到了国家“863”计划和国家自然科学基金的资助。更多还原

【Abstract】 With the rapid development of global communication service, wireless mobile communication technology regarded as future personal communication main means is receiving much attention. Code division multiple access (CDMA) systems are interference-limited. So the design of the receiver is very important. How to eliminate the CCI, MAI and multipath fading becomes the essential factor of improving system perfonnance. Multiuser detection and smart antenna are two inspiring key technologies. The estimation of users’ equivalent waveform, multipath fading information and the application of array antenna in the receiver can be addressed in this thesis. The main task is summarized as follows:First, two estimation algorithms of wireless mobile long-term fading channel in AWGN environment are proposed. Signal subspace method and independent component analysis are applied to the estimation problem respectively. Simulations verify the effectiveness of these methods.Array antenna is introduced in the receiver to improve system performance in the second part. Apart form the analysis of traditional space-time receive, a simplified space-time receiver is provided on the basic of the decrease of the system complexity. Using the property of the used waveform in the system we implement a new algorithm adapted to DS-CDMA system whose performance is perfect.The paper is supported by "863" High-Tech program and National Natural Science Foundation of China.更多还原