Lifetime Enhancement of a WSN Through Duty Cycle in an Aggregation Based Cooperative MIMO Framework

Duty cycle is a well-known approach for energy saving as well as life time enhancement of a wireless sensor network having scarce energy resources. In this paper, we have achieved energy savings by introducing duty cycle in an aggregation based cooperative-MIMO (CMIMO) framework. In the proposed CMIMO framework, instead of opting for the complete centralized or distributed approach, an optimum number of node performs aggregation and long haul transmissions which not only saves energy but also increases the reliability of the network. The aggregator and the long haul link nodes are selected based on the residual energy level. The role of a node to behave as an aggregator and/or long haul link node is rotated after certain number of rounds and duty cycle is implemented accordingly. This ensures load balancing which eventually leads to lifetime enhancement. The effect of varying the cluster size, the number of aggregator nodes and the long haul links on the average energy consumption have also been analysed. The result shows that by introducing duty cycle in an aggregation based framework contributes to a significant amount of energy savings. On an average 42.50% of energy is saved in the proposed framework when compared CMIMO without any data aggregation. And this energy saving is up to 99% when compared to the conventional single node transmission.