Energy efficient exponential decision MAC for energy harvesting-wireless sensor networks

Energy Harvesting Wireless Sensor Networks (EH-WSNs) are of great interest to researchers due to their various applications in areas such as environmental monitoring, process monitoring and tracking surveillance systems. Sensors are deployed in hostile environment in random fashion making a self-organized topology. Medium Access Control (MAC) plays a vital role in the power saving mechanism of EH-WSNs. This paper proposes two MAC schemes by considering the exponential decision using the residual energy of each of the individual sensor nodes. In the first scheme, Exponential Decision MAC based on Current Residual energy (ED-CR) takes into account only the current residual energy and thereby adjusts the duty cycle of each sensor nodes dynamically. In the second scheme, each sensor node estimates the prospective increase in residual energy with time using Exponential Decision-based on Prospective Increase in Residual energy (ED-PIR) so that it can reduce off time of the duty cycle more aggressively when possible and thereby achieve more energy savings. NS2 simulated results show that ED-PIR and ED-CR have better performance than static Receiver-Initiated MAC (RI-MAC) and its linear decision dynamic duty cycled approach.