Positioning Technology, Mobile Communication Systems

Research on position location technologies for mobiles in mobile communications systems has been activated in recent years.Position location based on TDOAs(time difference of arrivals) is the most-suggested solution of position location application.This dissertation,first,deals with one typical CDMA(code division multiple access)wireless mobile communications system,including the wireless channel,the frequently-used signal processing methods for transmission and reception of CDMA signals,and establishes one relatively complete CDMA communications system.Then,the location technology based on TDOAs and its execution in one system are dealt in detail.Many simulations and performances measurements are made on this technology with detailed comment on the results.Lastly,the development of PLD (programmable logic devices) is dealt and one correlator of received CDMA signals based on PLD is developed.Some simulated results and synthesized results are given.Mobiles' position location measurements and simulations affirm the feasibility of this technology and the efficiency of corresponding algorithms.Moreover,the correlator of received CDMA signals can be used not only in correlating received CDMA signals,but also in solving TDOAs.The appendix deals with,exclusively,one system for high speed object's position location and track.The position location method,the track method and some simulated results in such system are included in this appendix.