HexNet: Hexagon-based localization technique for wireless sensor networks

Developing efficient localization techniques to allow sensors to estimate their positions has been a hot research topic for long time. Sensory readings are almost meaningless if they are not associated with the locations in which these readings were taken. Getting location information through recording positions manually or through an expensive GPS chip are not valid options for sensor networks. We propose and evaluate, a new localization protocol for sensor networks. Although our technique is presented using only a single anchor, it can be extended easily to benefit from the existence of several anchors. The proposed technique starts by hypothetically tiling the deployment area around the anchor node using identical hexagons. After that, the closest sensor node to the center of each of these hypothetical hexagons is determined, we refer to these nodes as backbone sensors. The positions of hexagon centers hence the positions of backbone sensors are estimated geometrically. After that, backbone sensors are treated as beacons and the positions of all non-backbone sensors are estimated using the centroid approach. Simulation results under noise-free and noisy conditions show that the proposed protocol achieves a localization accuracy that makes it useful for most WSN applications.