Wireless Location Technology Research Based On TDOA And TOA

Nowadays domestic 3G technology is market-oriented. The location based services provide fun, entertainment and business transaction for consumers. Meanwhile the booming Internet of Things provides more applications for location based services. Therefore, the research of wireless location technology has important theoretical significance and application value. This paper mainly studies the wireless location technology based on TDOA and TOA. The main task includes the following aspects:(1)This paper researches the status of domestic and international positioning techniques, and the principle of wireless location. Then several common positioning methods are described. The study focuses on Fang algorithm, Chan algorithm and Taylor series expansion algorithm of the cellular network positioning technology. The experiments compare the merits and weakness of these types of algorithms, and analysis the performance.(2) This paper improves the location algorithm based on Kalman Filtering. The gain of Kalman filtering is regulated by predicted residual error. The predicted values of Kalman filer are reconstructed by average errors of NLOS. Then the location of the object is calculated by Chan algorithm. The simulation results show that our algorithm reduce the positioning error significantly.(3)Through the study of RSA algorithm, this paper gives an improved algorithm. After preprocessing of the measured data, estimated location of the object is got by RSA and extremum method. Then the final object location is calculated by processing two weighted location results. The simulation shows that this algorithm improves the accuracy.