Journal of Communications
In rechargeable wireless sensor networks, owing to the current energy conversion technology limitations, the energy harvested from surrounding environment usually is not enough to continually power sensor nodes. Therefore, the nodes have to operate in a very low duty cycle, which means nodes have to activate shortly and stay in the sleep state most of the time in order to recharge the energy. On the other hand, due to sporadic availability of energy, nodes must adjust their duty cycles continuously. Hence, packet delivery latency is critical in rechargeable WSNs.