The Research Of Wireless Location Technology In Mobile Communication System

This thesis aims at the research of wireless location technology based on time-related measurements in Wireless Communication System.After analyzing the previous research in wireless location extensively, the thesis analyzes and compares, by simulation under some common mobile channel environments, the existing basic location algorithms. The simulation results show that, Taylor algorithm and Chan algorithm are easy to realize and can achieve good location accuracy. Therefore, in order to evaluate the performance of the two basic algorithms in detail, the corresponding performance is evaluated by RMSE. In this simulation, many relative parameters are examined such as the cell size, the number of base stations taking part in the location service, equipment measurement errors, NLOS effect etc. The simulation results show that, Taylor algorithm and CHAN algorithm fit in various simulation environments. However, in order to meet the so-called E-911 demand, these algorithms must be modified.Based on the above investigation, two new algorithms called Genetic Algorithm and Particle Swarm Optimization based on TDOA measurements is put forward. In the research, Genetic algorithm and Particle Swarm Optimization algorithm are put in the same environment for simulation and evaluation with Taylor and Chan Algorithms. The results show that, Genetic algorithm and Particle Swarm Optimization can improve significantly the location performance.