Research Of Location And Tracing Algorithm In Cellular Networks Based On TDOA

Wireless location in the cellular system is a kind of business which has a broadmarket prospect, and its basic principle is through many measurement and estimation ofcharacteristic parameters, so as to locating and tracking the mobile users. In the cellularlocation system, which objectively from the mobile terminal by attachments facilities,such as field intensity, the time of arrival(TOA), the difference of time arrival(TDOA),or angle of arrive(AOA), etc. And then, through the appropriate location algorithmcalculate the approximate location of mobile terminals. In the wireless communicationchannel of the cellular network environment, due to the mobile communication channelnoise, multipath disseminating, non line of sight and other adverse factors, cellularwireless location system is difficult to achieve a higher positioning accuracy. So how toweaken interference factors as the cellular network wireless location and trackingproblems and areas of focus. The thesis aim at noise problem of the wireless location inthe cellular system, research the TDOA methods of locating and tracking.First of all, the thesis analyzed several major methods for wireless cellularlocalization are introduced in this thesis, and the paper choose the TDOA method. Then,we introduce the cellular location system in detail, including the topology constructionof the cellular location system, the measurement and estimation of time parameter. Atsame time, we also introduce the channel model which suit the location of the cellularlocation system, the assessment indicator of the wireless location and the main reasonwhich influence the accuracy of the wireless location.Then, we derive Taylor Algorithm and Chan Algorithm based on TDOA method.At the same time, we research and analysis the combination of Elman cellular networksand Chan Algorithm. Through the simulation, we analysis and compare TaylorAlgorithm、Chan Algorithm with Chan Algorithm based on Elman cellular networks.Thirdly, for the Tracing is a special occasion in the location service application, thethesis introduce several common method: Kalman Filter (KF), Extended Kalman Filter(EKF), Unscented Kalman Filter (UKF) and Particle Filter (PF), and analysis theParticle Filter based on TDOA method in detail. Through the simulation, we analysis and compare UKF with the Particle Filter based on TDOA method.In the end, this thesis makes a conclusion of problems to be resolved and discussesthe research points which are worth to study in future.