Efficient single-anchor localization in sensor networks

The intrinsically location-aware applications of sensor networks and the need for location-based optimized routing make efficient and accurate location determination of sensor nodes essential. It is practically and economically infeasible to equip all sensor nodes with GPS receivers. A few GPS equipped anchors are therefore used to determine the location of sensor nodes in the field. Localization techniques which use lateration require at least k+1 anchors to compute the location of all the sensor nodes under their coverage area in a k dimensional plane. In a two-dimensional plane, for example, sensor nodes which are not in the range of at least three anchor nodes cannot estimate their location. In sensor networks it is often difficult to set up three anchors to cover all sensor nodes. We propose a simple technique which requires only a single anchor node to determine the location of sensor nodes in a two-dimensional plane.