Integer linear programming formulation of optimal beacon placement problem in WSN

In wireless sensor networks (WSNs) localization systems are required to provide position information of sensor nodes. Location information of sensor nodes with unknown physical coordinates is acquired with the help of beacons or anchors. Beacon placement is one of the prominent factors that shape the localization performance in sensor networks. Placing more beacons in a network is generally not a cost-effective idea. However, a carefully designed technique can increase the accuracy by placing a limited number of beacons. This paper presents an integer linear programming(ILP) formulation of optimal beacon placement (OBP) and also prove that the OBP problem is NP-hard. Requirement based beacon placement algorithm is proposed to optimize number of beacons to cover the entire WSN. Simulation result shows that the proposed beacon placement scheme is effective in a sensor network with high node density.