Study Of Channel Parameters Estimation And Space-Time Multiuser Detection

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.