Abstract: We develop an algorithm that computes the Euclidean distance between beacon node and orphan node, estimates the position of orphan node by maximum likely-hood algorithms, and acquires a more precise position by the WLS calculating iteratively. Three methods are given to solve the problems of multihops Euclidean distances. Based on a new opinion over the weighted matrix, the algorithm makes overall plans to look for orphan nodes up to the localization conditions. The orphan node becomes assistant beacon node to aid localization after being localized. Simulation results demonstrate that the average error of positioning is lower and coverage is better when connectivity is 8.

Key words: centralized computation, E-Euclidean, localization, wireless sensor networks