A Practical Relay Scheduling Scheme for Wireless Sensor Networks with Energy Harvesting

The use of cooperative communication technology in energy harvesting sensor networks is one of the most viable solutions to overcome the power limitations of the battery-powerd sensor networks. However, combining cooperative communication and energy harvesting in a network requires an efficient and a practical relay usage scheduling scheme to maximize the overall packet delivery ratio. This paper considers a wireless sensor network with energy harvesting and cooperative communication, and proposes a practical scheme that maximizes the packet delivery ratio of the system. The results show that our scheme provides almost the same performance of the threshold based scheme (state-of-the-art scheme) using the same system parameters. Compared to the threshold scheme that has a tunable parameter (threshold value) for each set of system parameters, the results show that our scheme does not require any tunable parameter to maximize the performance. In the threshold based scheme, if one of the system parameters changes, the sensors need to tune the threshold level at a new value to maintain the maximum performance. Tuning the threshold at a certain value requires simulating the system at different threshold levels to get that tunable value. This is not easy and might not even be practical to implement especially in networks of thousands of sensors with unstable parameters. So, no need for any tunable parameter makes our scheme easier and more practical to be used. Also, it makes our scheme more flexible to adjust the performance of the source and relay to ensure fairness between them.