Sensor node localization in the presence of limited anchor nodes

Abstract

Wireless sensor networks hold the promise of many new applications in the area of monitoring and control. In most applications if location information of the sensing node is not available, measured data from sensing node become meaningless. Iterative techniques are widely used to enhance localization coverage. Main problem with iterative technique is error propagation. So this research proposes a mechanism to improve the localization coverage as well as a new technique to minimize the error propagation. new Localization coverage improvement is based on the 2 hop neighbors (referred as “New method”). When a location unknown node has only 2 anchor node in its radio range, location can’t be determined. But if 2 hop anchors are available with satisfying a certain criteria location can be determined as shown in this research. In Iterative techniques once location is determined it is upgrade to anchor status. Ifthis node upgrade is handled more carefully error propagation can be minimized. So this research proposed Distance Measurement Error based node upgrade to minimize the errors. Simulations were carried out for three simulation scenarios to demonstrate the performance improvement of the proposed techniques. According to the simulation results obtained, 7% improvement for localization coverage and 4% improvement for localization accuracy from the DME based anchor node upgrade were achieved with respect to standard trilateration.