This article is part of the series Signal Processing for Location Estimation and Tracking in Wireless Environments.

Open Access Research Article

Exploring Landmark Placement Strategies for Topology-Based Localization in Wireless Sensor Networks

Farid Benbadis1*, Katia Obraczka2, Jorge Cortés3 and Alexandre Brandwajn2

Author Affiliations

1 Laboratoire LIP6/CNRS, UMR 7606, Université Pierre et Marie Curie, 4 place jussieu, 75005 Paris, France

2 Department of Computer Engineering, University of California, Santa Cruz, CA 95064, USA

3 Department of Mechanical and Aerospace Engineering, University of California, San Diego, CA 92093, USA

For all author emails, please log on.

EURASIP Journal on Advances in Signal Processing 2008, 2008:275658  doi:10.1155/2008/275658


The electronic version of this article is the complete one and can be found online at: http://asp.eurasipjournals.com/content/2008/1/275658


Received:31 March 2007
Revisions received:24 September 2007
Accepted:21 December 2007
Published:31 December 2007

© 2008 The Author(s).

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.

Abstract

In topology-based localization, each node in a network computes its hop-count distance to a finite number of reference nodes, or "landmarks". This paper studies the impact of landmark placement on the accuracy of the resulting coordinate systems. The coordinates of each node are given by the hop-count distance to the landmarks. We show analytically that placing landmarks on the boundary of the topology yields more accurate coordinate systems than when landmarks are placed in the interior. Moreover, under some conditions, we show that uniform landmark deployment on the boundary is optimal. This work is also the first empirical study to consider not only uniform, synthetic topologies, but also nonuniform topologies resembling more concrete deployments. Our simulation results show that, in general, if enough landmarks are used, random landmark placement yields comparative performance to placing landmarks on the boundary randomly or equally spaced. This is an important result since boundary placement, especially at equal distances, may turn out to be infeasible and/or prohibitively expensive (in terms of communication, processing overhead, and power consumption) in networks of nodes with limited capabilities.

Publisher note

To access the full article, please see PDF.