A three dimensional localization algorithm using a mobile anchor node under wireless channel

Localization is one of the crucial issues in wireless sensor networks. In range-based mechanisms, the nodes obtain pairwise distances or angles with extra hardware for high localization accuracy. On the other hand, the range-free schemes obtain lower localization accuracy at low hardware cost. To improve location accuracy, we present a three dimensional range-free localization scheme by using a mobile anchor node equipped with a GPS. The mobile anchor node carried in an aero plane flies over the sensor node area and broadcasts its current position periodically. A sensor node in the area computes its own location using the position of the mobile anchor node where the maximum RSSI is received by the sensor node. In our scheme, neither extra hardware on each sensor node nor communications between sensor nodes is needed. Our proposed scheme is simulated in Opnet and simulation results show that our scheme performs better than other range-free localization algorithms using mobile beacon nodes.