Channel Estimation And Receiver Research Based On Turbo Principle For UWB System

Ultra-wideband (UWB) communication has been the subject of extensive research in recent years due to its unique capabilities and potential applications, particularly in short-range multiple access wireless communications.The subject of this thesis is the channel estimation technology and receivers based on TURBO principle in UWB. In order to utilize the resoluble ability of signals and improve resistant ability to multipath fading, the Rake receiver is a good option. But proper Rake operation requires information about the delays and attenuations of the channel paths which is difficult to obtain. In the recent years, excellent forward error correction capability of turbo codes has been exploited which can lead to highly power and bandwidth efficient in wireless communication systems. Combining two technologies together may produce a new scheme. Firstly, this thesis investigates the application of turbo codes as channel code in UWB, and then introduces TURBO principle. Aiming at UWB indoor multipath channel, we propose a channel estimation algorithm with training bits. Finally, we propose an iterative channel estimation algorithm based on TURBO principle. This method fully utilizes the soft outputs of channel coder, and regards it as prior information. The simulation results show that two algorithms can efficiently estimate channel parameters, but the late method has better performance than the former when channel is time-variant.Finally, there are conclusion and prospect.