An Improvement CHAN Algorithm Based on TOA Position

An improvement CHAN position algorithm based on TOA parameters is proposed in this paper.The first step estimation results can be gotten by using coordinate shift method to eliminate the unknown parameter in the location function.The geographical structure of the base stations and the distances of arrival between base stations and mobile station have the different 'contribution' degree to position error through the analysis of the error of the first step estimation result.According to the principle that the weight is inverse to the 'contribution' degree,we propose the method of virtual base station to reduce the total system errors and improve the precise of the position estimation.The simulation results also verify the ability of this method.