Table of Contents
ISRN Sensor Networks
Volume 2013, Article ID 356231, 11 pages
Research Article

An Anchor-Free Localization Scheme with Kalman Filtering in ZigBee Sensor Network

1Division of Computer Engineering, Graduate School of Engineering, University of Hyogo, 2167 Shosha, Himeji 671-2280, Hyogo, Japan
2Mitsubishi Electric Control Software Corporation, 1-1-2 Wadamisaki-Cho, Hyogo-Ku, Kobe 652-8555, Hyogo, Japan
3Step One Limited, Urban Ace Sannomiya Building, 4-1-22 Onoe-Dori, Chuo-Ku, Kobe 651-0088, Japan

Received 27 December 2012; Accepted 23 January 2013

Academic Editors: T.-Y. Juang and L. Reggiani

Copyright © 2013 Teijiro Isokawa et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.


A localization scheme for wireless sensor networks is proposed and its performances are investigated in this paper. The proposed scheme is an anchor-free scheme, in which no geometrical information of sensor nodes is required for their localization. Thus, only local interaction among sensor nodes is used to estimate their locations. This scheme employs the link quality indicator and hop count between sensor nodes for location estimation. A weighted averaging and Kalman filtering schemes are incorporated in order to reduce the effects of the measurement errors in the obtained values of the link quality indicator. We performed experiments by implementing the proposed scheme on ZigBee sensor modules. The results of our experiments indicate that estimation could be successfully performed for networks comprising four sensor nodes.