Saving Relay Time in a Heterogeneous Wireless Sensor Network

In a Wireless Sensor Network (WSN), it is common to use high end nodes known as relay nodes with more battery power and communication range for forwarding data to the base station. To assist sensor nodes if the relay nodes are added, communication becomes better because relay nodes are used to bridge the communication or routing. However, this is also important to keep the minimum number of relay nodes working to save the network cost. Most of the existing research focuses on placing the relay nodes in wireless sensor networks. It may happen that the different relay nodes forward data of the different sensor nodes on the basis of the availability. When data is not forwarded, relay nodes may be in sleep condition. In this paper, we provide a load balancing strategy to find the minimum number of relay nodes to be working with the goal of having longer network lifetime. We validate our claim by providing simulation results and we find it is possible to save a significant part of duty cycle using our model.