TITLE:
Group Target Tracking in WSN Based on Convex Hulls Merging
AUTHORS:
Quanlong LI, Zhijia ZHAO, Xiaofei XU, Tingting ZHOU
KEYWORDS:
Sensor Networks, Target Tracking, Group Target, Convex Hull
JOURNAL NAME:
Wireless Sensor Network,
Vol.1 No.5,
December
16,
2009
ABSTRACT: When a mass of individual targets move closely, it is unpractical or unnecessary to localize and track every specific target in wireless sensor networks (WSN). However, they can be tracked as a whole by view of group target. In order to decrease the amount of energy spent on active sensing and communications, a flexible boundary detecting model for group target tracking in WSN is proposed, in which, the number of sensors involved in target tracking is adjustable. Unlike traditional one or multiple individual targets, the group target usually occupies a large area. To obtain global estimated position of group target, a divide-merge algorithm using convex hull is designed. In this algorithm, group target’s boundary is divided into several small pieces, and each one is enclosed by a convex hull which is constructed by a cluster of boundary sensors. Then, the information of these small convex hulls is sent back to a sink. Finally, big convex hull merged from these small ones is considered as the group target’s contour. According to our metric of precision evaluation, the simulation experiments confirm the efficiency and accuracy of this algorithm.