Adaptive Sensor Activation and Mobile Energy Replenishment for Wireless Rechargeable Sensor Networks

Recent studies have shown that environmental energy harvesting technologies have the potential to provide perpetual operation to rechargeable sensor networks. However, due to the large variations of the ambient energy source, such networks could only support low-rate data services and their performance is influenced by numerous unpredictable environmental factors. In order to bridge this gap to yield high and controllable recharge rates, we import the novel wireless power transmission technology to rechargeable sensor networks. We propose that by combining traditional mobile data sink whose role is data collection with wireless energy replenishment would suffice our needs to offer shorttime high rate data service and refill sensor’s battery energy at the same time. In this paper, a new network architecture based on wireless energy replenishment is presented. We establish an analytical model to show the potential using probabilistic sensor activation and mobile energy replenishment could improve the system performance and elongate network lifetime. Second, we introduce three protocols (1) static activation on sensors (2) linear adaptation activation with prioritized recharge (3) battery-aware activation with selective recharge. Finally, we compare these protocols by extensive simulations and show that a smart design of sensor activation with effective control of mobile energy replenishment can provide significant performance improvement and elongate the lifetime of the network by over ten times even in the worst case.