NLOS Error Mitigation Algorithm Research Based On Wireless Location

This thesis aims at the research of NLOS error mitigation algorithm based on Wireless Location Technology in Wireless Cellular Network. After analyzing the previous research in wireless location extensively, the thesis analyzes the existing basic location algorithms. For TDOA, TOA and hybrid location algorithms based on time-related measurements are the research hotspot at present, this thesis analyzes mostly three algorithms. By simulation under Gauss mobile channel environments, evaluating performance of diversified algorithms in detail. These researches establish the base to investigate NLOS error optimization algorithm.Analyzing the NLOS error in detail, which has become a crucial factor to influence mobile user location precision in diversified cellular network types. Optimizing NLOS error by NLOS error identification and mitigation. By simulation comparing the optimization results with unoptimizable results and showing the improvement effect after mitigating NLOS error.This chapter proposes a linear adding weight algorithm to mitigate NLOS error based on nonlinear problem for TDOA/AOA hybrid algorithm. Simulation results show that the impact of NLOS error is reduced after using this algorithm and enhancing location precision. It can obtain better effect than original algorithm.Bring forward a new BS selection location algorithm. Firstly judging whether there were NLOS errors in the measurements samples. Secondly selecting two BS containing the smallest NLOS error and reconstructing LOS measurements. Lastly used three BS algorithm to compute MS location. Simulation results show this algorithm can mitigate NLOS error commendably and obtain better location effect.