Hilbert mobile beacon for localisation and coverage in sensor networks

Wireless sensor networks (WSN) constitute a major area of research developing at a very fast pace. Target localisation and coverage are core issues in the field of WSN and represent constraints that affect the effectiveness of WSN. This article focuses on localisation and coverage and identifies a relationship of dependence between the two issues. Throughout this article, a localisation algorithm is proposed and also an energy efficient approach that aims to preserve coverage. The use of a mobile beacon is suggested to divide the region of interest into unit squares following the same method used in the Hilbert space filling curve. A proper choice of the order of the Hilbert curve (i.e. the region subdivisions) is studied to guarantee the localisation of all nodes as well as the total area of coverage. The mobile beacon assists to determine the physical location of undetected nodes by sending beacon packets while traversing the region of interest. It also locally derives an activity scheduling between nodes with a relatively low cost in terms of energy spent by nodes compared to other approaches. In order to validate the effectiveness of the above proposed approach, a series of experiments have been conducted and will be mentioned throughout this article.