A Novel Approach for Establishing Connectivity in Partitioned Wireless Sensor Networks Using Beamforming Techniques

Network connectivity is one of the major design issues in the context of Wireless Sensor Networks (WSNs). Due to diverse communication patterns, some nodes lying in hightraffic zones may consume more energy and eventually die out resulting in network partitioning. This gives rise to a situation when some alive nodes are trapped in a disconnected cluster and do not have enough radio range required to communicate their data to destination, i.e. to a sink or a relay node connected to the main part of the network. This phenomenon may deprive a large number of alive nodes of sending their important timecritical data to the sink. In this paper, we propose a virtual antenna based cooperative beamforming approach in order to retrieve valuable data from these disconnected nodes. In the proposed scheme, the sensor nodes in isolated partitions work together to form a directional beam which significantly increases their overall communication range to reach out a distant relay node connected to the main part of the network. The proposed methodology of cooperative beamforming based partition connectivity works efficiently if an isolated cluster gets partitioned with a favorably large number of nodes. Furthermore, we propose a cooperative beamforming based scanning mechanism to search for the nearest alive node connected to the main part of the network. The proposed mechanism is then elaborated through simulation results. The simulation result shows that our proposed mechanism achieves upto 70% partition reduction through beamforming as partition healing.