Relay node placement to establish full connectivity in directional sensor networks

The deployed sensors within a network should be connected to ensure reliability of the network. For a disconnected network, relay nodes are placed to form a well connected network. Relay nodes have a higher transmission range, energy reserve and data processing abilities as compared to sensor nodes in a network. However due to high cost of relays, optimal placement is necessary. We use heuristics to solve the NP-Hard relay node placement problem. In this paper, we propose an algorithm to ensure that the all the sensor nodes are connected to the data sink node using the least number of relay nodes. The simulations carried out extensively prove the performance of the proposed algorithm.