Efficient Boundary Estimation for Practical Deployment of Mobile Sensors in Hybrid Sensor Networks

We address the deployment issues in a hybrid sensor network consisting of both static and mobile sensor nodes. Existing deployment schemes often assume either known regular boundaries of the region, or that mobile sensors are able to detect the region boundary. This is overly idealistic especially for unknown, outdoor environments. In our proposed two-phase deployment scheme, following their initial random deployment, the static sensors estimate the boundary of the unknown region by using the right-hand rule. This phase results in the identification of static boundary nodes, B-nodes. The mobile sensors are assumed concentrated at one or more points within the target area. In phase II, mobile sensor nodes spread in the target area in a distributed manner using one of the proposed variations of the virtual force algorithm. Neighboring B-nodes form a Virtual Boundary and exerts repulsive forces on mobile nodes to keep them in the target area. Using simulations, we demonstrate the effectiveness of our proposed scheme in uniformly deploying mobile sensor nodes in a hybrid sensor network