Experiments with a “pseudo-gradient” algorithm for target localization using wireless sensor networks

This paper proposes a novel scheme for target localization using a deployed wireless sensor network (WSN). The goal is to have mobile autonomous robots navigate from any point within the WSN-covered region to an identified target through interaction with the WSN. Reaching the target is achieved in two ways, by: (i) producing gradients in the WSN region that give the maximum peak closest to the target, (ii) having the sensors guide the robot to the target efficiently. This scheme uses the topology of the network to create a navigation path. The robot follows the pseudo-gradient in the WSN to reach the global maximum. In this method, there is no global coordinate reference available for the region i.e., the WSN and robots only make use of the relative neighborhood information to attain their goal. The performance of the scheme is analyzed in simulation using a variety of node-densities.