Ultra-wideband Channel And Receiver Performance Analysis

UWB have been abstracted and get much attention in last yeara. This communication pattern use ultra narrow pulse to transport data pulse. Its transmission speed is about 500M per second and even higher, and form the bandwidth about several GHzs. UWB is mainly in indoor condition use as high speed data transmission, and its transmit space of availability commonly in 10 meters because of the limited in the send power. There is multipath interfere in indoor condition lead to decline and the decline mainly in path loss and multipath loss, so it is necessary to study the key techniques of UWB communication.This thesis focuses on the key techniques of UWB communication steeply:1. The thesis discusses the modeling of UWB impulse and UWB impulse forming methods, gives the detailed methods of UWB pulse forming, which can be adopted by differently complicated UWB transceiver systems.2. Emphases of this thesis are in the multi-path channel and Rake receiver. The thesis offers the simulation of IEEE 802.15.3a commendatory four channel modeling and the contrast of effects caused by AWGN and multi-path channel to the performance of Rake receiver, also considers the achievement of complexity and performance of Rake receiver which adopts the method of MRC.3. Based on the shortage of the standard channel model, this thesis adopt a method based on Fourier Transform to improve on the speed of the channel simulation, and put forward a method based on upsampler and downsampler to obtain the character of channel accord with the actual frequency band of transmission system.4. This thesis analyses the effects of multiuser interference to the Rake receiver, then put forward methods to improve the performance of multiuser access system.5. This thesis propose transmitting and receiving schemes for UWB. By analyses and simulations, we prove that TH UWB communication system with STBC yields better bit error rate(BER) performance than traditional system. We also prove that BER performance becomes better when diversity order increases.