Localization in wireless sensor networks using a mobile anchor node

In wireless sensor networks (WSN), sensor location plays a critical role in many applications. Having a GPS receiver on every sensor node is costly. In the past, several approaches, including range-based and range-free, have been proposed to calculate positions for randomly deployed sensor nodes. Most of them use some special nodes, called anchor nodes, which are assumed to know their own locations. Other sensors compute their locations based on the information provided by these anchor nodes. This paper describes MACL, a mobile anchor centroid localization method, which uses a single mobile anchor node to move in the sensing field and broadcast its current position periodically. The proposed method is radio-frequency based, so no extra hardware or data communication is needed between the sensor nodes. We use simulations and tests from an indoor deployment using the Cricket location system to investigate the localization accuracy of MACL, and find that the localization method is principle simple, less computing and communication overhead, low costly, and flexible accuracy.