Distributed resource allocation for power beacon-assisted wireless-powered communications

In this paper, we investigate the optimal resource allocation in a power beacon-assisted wireless-powered communication network (PB-WPCN), which consists of a set of hybrid access point (AP)-source pairs and a power beacon (PB). We assume that all sources have no embedded power supply. Thus, each source first harvests energy from the signals broadcast by its associated AP and/or the PB in the downlink (DL) and then uses the harvested energy to transmit its information to the AP in the uplink (UL). The PB is deployed to assist the APs during the DL wireless energy transfer (WET) phase. We formulate an optimization problem for the considered network, in which the DL WET time of each AP-source pair and the energy allocation of the PB are jointly optimized to maximize the weighted sum-throughput of all AP-source pairs in the UL. We also propose a waterfilling-based algorithm to solve the formulated problem in a distributed manner. Numerical results are performed to validate the convergence of the proposed algorithm and demonstrate the impacts of various system parameters.