| Ultra WideBand（UWB）is a novel technology in wireless communication field. With itsadvantages such as high transmitting speed, better anti-interference ability, lower power loss,better covering and anti-multipath fading performance，UWB has wide application prospect inthe fields of short-distance high speed wirless personal area network, radar tracking, accurateprecisioning and so on. Especially it has a great of advantage in indoor positioning. However thebandwidth that UWB takes is so wide that it covers the bands that many actual communicationsystems are taking. So FCC prescribes that the PSD in the frequencies from3.1GHz to10.6GHzof UWB can’t exceed-41.25dBm, thereby UWB signal will not affect the natural working ofother wireless systems. But other systems such as satellite-based and earth-based system signal,with their transmitting powers are higher in the same frequencies, they will make someinterference and affect to the UWB receiver, and it is an austere challenge to precise position ofUWB indoor positioning system.In this paper, the basic definition and characteristics of UWB technology is introducedfirstly, and then the theory amd channel transmitting model of UWB indoor position system areanalyzed. Based on it, the different interference of UWB has are made model and emulated, thechange of the UWB performance in the situation of different interference exists is analyzed.Finally the paper researches the co-channel interference of UWB system, and a kind of analysismethod based on co-channel interference guard threshold of UWB co-channel interference isadvanced. The specific research work of the paper is as follow:Firstly, based on UWB indoor positoning system, its theory and structure is analyzed, andMB-OFDM-UWB signal is made model and emulated. Secondly, based on the research on fourkinds of UWB indoor channel model that IEEE.802.15.3a group recommends, the UWB channelimpulse response is emulated and analyzed. Thirdly, based on the NBI trait, the effect that NBImakes on the MB-OFDM-UWB error code probability performance in the presence of tone,multiton and partial-band interference with different SIR is analyzed, and some methods ofeliminating NBI are given. Finally, based on the transmitting trait of UWB and its co-channelinterference signal, corresponding path loss model is chosen, and a kind of UWB systemco-channel interference analysis method based on the co-channel interference guard threshold isadvanced. And corresponding math analysis model is built according to the satellite-based andearth-based co-channel interference trait, and corresponding co-channel interference determinantrule and quantitated evaluating method of interference degree are advanced. Then the defendmeasures of the UWB wireless system co-channel interference is given, it settles the foundationfor the EMC of UWB system and other wireless system. |
PDF Full Text Request