Study On Rake Receiver Technology & Coexistence Characteristics In UWB Telecommunication System

UWB wireless communication technology is one of the advanced technologies in wireless communication field presently. It has many advantages, such as high transmission rate, strong resistance to interference, good secrecy performance etc. Further more, UWB wireless communication has an obvious characteristic that it puts into practice the reuse of frequency resource, so as the frequency spectrum resource has become more and more precious, it's acquiring much attention.In this thesis, we particularly focus the study on the two key technologies of UWB communication systems: Rake receiver technology and electromagnetism compatible technology. Discussed the receiver performance of MRC-Rake,MMSE-Rake and MRC-Rake-Equalizer in DS-UWB system. In the presence of multi-path fading, inter symbol interference and narrowband interference, MRC-Rake performance degrades, while using MMSE-Rake, its performance advanced, however with increased computational complexity. When we selected MRC-Rake-Equalizer receiver, its realization is more convenient, and from the result of simulation, we obtained it's increased performance. Also as the number of equalizer fingers increases, the performance of MRC-Rake-Equalizer is advanced, and as the accretion of SNR, the advantage gets obvious. As for the study of electromagnetism compatible technology, instance GSM900 and GSM1800 receiver. Simulation results we obtained showed the safe distance with single DS-UWB equipment, and the safe density with multi DS-UWB equipments. We further concluded that, by modulating the ratio of NLOS and LOS interference source, it's possible to restrict the interference of DS-UWB systems to other wireless communicate systems to the range, which we can accept.