Distributed Energy Cooperation in Multicell Wireless Powered Communication Networks

This paper investigates a general multicell wireless powered communication network, in which multiple access points (APs) provide energy to the Internet of Things devices (IoT-Ds), and the IoT-Ds utilize the harvested energy to send information back to their associated AP. Within the network, a scheme enabling information and energy cooperation among APs is proposed to realize data transmission among cells as well as mitigate the risk of energy supply-demand imbalance. Based on such cooperation scheme, APs with surplus energy can share energy with other APs with deficient power supply, and the energy efficiency maximization problem is studied for the considered network of two practical scenarios including APs with energy-storage devices (ESDs) and without ESDs. To solve the optimization problems, a novel distributed scheme is designed to jointly the optimize energy cooperation strategy and time allocation, where each AP communicates only with neighboring APs to independently update its own optimal decision. Different from the centralized methods requiring global parameters such as all channel status information (CSI) that may be unavailable, APs in the developed distributed scheme jointly undertake the computational tasks without knowing all CSI. This results in faster convergence and higher scalability for multicell networks compared to the centralized schemes. Finally, simulation examples of two scenarios are presented to validate the performance of the proposed distributed scheme.