Calibrating problems of wireless sensors network is researched

and a locating and orienting algorithm in an unknown scene under surveillance of a set of wireless sensor network that have been deployed there is proposed.This self-calibration prob1em is solved using a number of source signals also deployed in the scene.The algorithm assumes each array can estimate the time of-arrival（TOA） and direction of-arrival（DOA） of every source.From this information the locations and orientations of sensors array can be worked out.It considers four sub-problems

in which the source signals or emission times are either known or unknown.Finally the necessary conditions for solving the self-calibration problem are developed

an optimized maximum likelihood algorithm and corresponding location error estimation are implemented.