The Research On Key Technology For DS-UWB Communication System

With its peculiar advantage, UWB technology now is becoming the focus of high-speed wireless communication technology research in short distance for the next generation. During the developing of UWB, the competition between DS-UWB and MB-OFDM comes into being. However, DS-UWB obtains more favor with its simple structure, easy to actualize, huge expansibility and higher speed. This paper focus on key technologies for DS-UWB communication system with m-BOK bi-orthogonal keying, pulse shaping, RAKE receiving, decision feedback equalizing and multi-user detection.First, this paper describes the basic principle and the main traits of DS-UWB, then the Spread Spectrum principle and bit error rate of m-BOK bi-orthogonal keying, the correlation characteristic, Spectral Peak matrix and the correlation matrix of RMS of bi-orthogonal ternary sequence of m-BOK keying have been analyzed, therefore the detection of system performance can be performed. Based on the carrier-less of DS-UWB, two baseband narrow pulse signals which suited for DS-UWB system are selected according to analysis for the time-frequency domain of various pulse signals. After that, this paper researches the receiver of one-user synchronous system and multi-user synchronous system based on UWB channel model, which is put forward and improved by Intel. Under one-user systematic environment, the model of ultra-wideband RAKE receiver and decision feedback equalizer (DFE) are designed, the effects on the performance of different parameter are analyzed. The simulation result proved that system performance is better by using RAKE receiver and decision feedback equalizer (DFE) than using RAKE receiver only. Under multi-user systematic environment, the operation principle of joint detection technique which eliminatesmulti-user interference is analyzed. We get the result that the joint detection technique has a less bit error rate than conventional multi-user detection technique. All the analyses are conducted in Matlab simulink. In the end, the illation of the frame format of data frame, the formula of throughput, the block diagram of data frame's hardware realization with some analyses of key technology are provided.