Target coverage maximisation for directional sensor networks

Wireless sensor networks (WSNs) have applications in many areas, such as biomedical observation, environmental monitoring, and battlefield surveillance. In order to reduce costs and improve reliability, target coverage has been an important problem for WSNs in recent years. In this paper, we investigate target coverage for a special kind of WSNs, called directional sensor networks, in which the sensors have limited monitoring distance and coverage angle. Given a set of targets and a set of sensors, we investigate how to assign proper directions for the sensors such that the number of covered targets is maximised. We show that it is NP-hard to find an optimal solution and we investigate both centralised and distributed approximation algorithms with provable performance guarantee. In addition, we analyse the problem itself from the combinatorics' point of view. Finally we also conduct a simulation experiment to evaluate the practical performance of proposed algorithms.