Event Localization and Actuation in Wireless Sensor Network without Locations
Shuo Lian, Jizhong Zhao and Yuan He
Event detection is a typical application of wireless sensor networks. The existing approaches of event detection usually employ certain event models that are constructed with prior domain knowledge. The resulting event detection processes appear to be cost-inefficient, which require either intensive data exchanges among neighboring nodes or caching large columns of history data. In this paper, we focus on the issue of event localization and actuation in wireless sensor network without locations. This involves two key tasks, namely detecting an event and identifying an area in the network where the event occurs. Motivated by the real-world observations, we propose a model-free approach for event detection and localization called CCD (Coding Cost based event Detection). Coding cost is a metric that quantifies the diversity of a set of sensor readings. Incorporated into the inherent data collection mechanism, CCD passively constructs a gradient map of coding cost throughout the network. An event is then detected and located where a change point of gradient appears. CCD is fully distributed and does not incur apparent communication overhead. Based on the gradient map, CCD further supports oriented event actuation to the event region. We implement CCD and evaluate its performance with extensive experiments and simulations. The results demonstrate that CCD is accurate, energy efficient, and scalable in a variety of sensor networks.
Keywords: Event Detection, Coding Cost, Wireless Sensor Network.