Abstract: Wireless sensor network is one of the key technologies of indoor location. Two aspects affect the positioning accuracy.One is ranging error,the other is the positioning calculation error.At Ranging stage,in order to solve the problems that signal propagation in complex environments has larger loss and affects the measurement accuracy,this paper proposed a method for estimating environmental factors based on the log-normal propagation path loss model,which can dynamicly correct measurements and reduce the measurement errors caused by the environment.At the positioning stage,in order to solve the shortcoming that a triangle and centroid algorithm cannot make full use of the data,this paper presented the weighted of the triangle and centroid algorithm to achieve a high-precision indoor positioning.Experimental results show that the algorithm can realize a high accuracy indoor positioning and is feasible.

Key words: Wireless sensor network,RSSI,Environmental factors to estimate,Weighted of triangle and centroid location algorithm,Indoor positioning