Telecom of New Zealand
Wireless Sensor Networks (WSNs) have attracted a great deal of research attention due to their wide potential applications such as battlefield surveillance, environmental monitoring and Intrusion Detection. Many of these applications require a reliable detection of specified events. Such requirement can be guaranteed only if the target field monitored by a WSN contains no coverage holes, that is to say regions of the domain not monitored by any sensor. Coverage holes can be formed for many reasons, such as random deployment, energy depletion or destruction of sensors. Consequently, it is essential to detect and localize coverage holes in order to ensure the full operability of a WSN.