Fast Localized Sensor Self-Deployment for Focused Coverage

We consider the focused coverage self-deployment problem in mobile sensor networks, where an area with maximum radius around a Point of Interest (POI) must be covered without sensing holes. Li et al. [9][10] described several algorithms solving this problem. They showed that their algorithms terminate in finite time. We present a modified version of the Greedy-Rotation-Greedy (GRG) algorithm by Li et al., which drive sensors along the equilateral triangle tessellation (TT) graph to surround a POI. We prove that our modified GRG (mGRG) algorithm is collision free and always ends up in a hole-free network around the POI with maximum radius in O(D) steps, where D is the sum of the initial distances of the sensors from the POI. This significantly improves the previous bound on the coverage time. The theoretical results are also validated by simulations.