A correlation model for MAC protocols in event-driven wireless sensor networks

In event-driven scenario, each event triggers a large number of nodes for sensing and transmission, thus the nodes encounter spatially-correlated contention due to correlation between nodes in spatial domain. To mitigate the correlated contention inside event area, a correlation model is proposed to describe the correlation characteristics of sensor nodes using sensing coverage of nodes. The C-INS algorithm using correlation model is introduced to exploit the spatial correlation inside the event area. Further, a random correlated event traffic model for NS-2 network simulator is developed to apply the results of model with existing MAC protocols for measuring the effectiveness of proposed C-INS algorithm. The simulation results using MAC protocols show that by exploiting spatial correlation network performance in terms of energy consumption and delay guarantee improves drastically. The analytical results of proposed correlation model also indicates better spatial correlation between nodes for higher density of nodes and larger sensing range.