Chain-based barrier coverage in WSNs: toward identifying and repairing weak zones

Abstract

Barrier coverage constructs a sensing barrier for detecting intruders crossing a belt region. Recent studies mostly focus on efficient algorithms to guarantee barrier coverage, with little consideration on the collaboration between individual nodes. Observing that in many situations, sensors naturally fall into several clusters (or components), for example when the sensors are deployed uniformly at random with a relatively low density, or when random sensors go down as a result of energy exhaustion, we propose to use chain as a basic scheduling unit for sensing and communication. A chain is a set of sensors whose sensing areas overlap with each other, and it can be extracted from a cluster. We present a distributed algorithm, named BARRIER, to provide barrier coverage with a low communication overhead for the wireless sensor networks (WSNs). The algorithm is able to detect weak zones that are often found in an initial deployment of a WSN, and repair them by adding an appropriate number of sensors. Theoretic analysis and simulations show that, compared with a representative previous algorithm, BARRIER significantly reduces the communication overhead and reparation cost in terms of number of sensors.