Optimal Resource Allocation for Wireless Powered Multi-Carrier Backscatter Communication Networks

Abstract

Backscatter communication (BackCom) is considered as one of important techniques to extend the lifetime of Internet of Things (IoT). How to achieve resource allocation (RA) is a key technique to optimize system performance. Existing RA schemes only focus on time scheduling under the fixed transmit power, however, the globally optimal solutions and power allocation are not considered. In this letter, we solve the total rate maximization problem for a multi-carrier wireless powered BackCom network, where a dedicated radio frequency power source (PS) transmits multi-carrier signals to a hybrid information transceiver device (ITD) during energy harvesting (EH) phase, and then the ITD deliveries the signals to the associated receiver during the information transmission (IT) phase. Our goal is to maximize the sum rate of the backscatter data rate and the transmission rate during the IT phase by jointly optimizing power allocation, time allocation, reflection coefficient, energy allocation coefficient, where the maximum transmit power constraint at the PS and the minimum circuit power consumption constraint are considered. Then an iterative RA algorithm is developed to find the optimal solutions. Simulation results confirm the superiority of the proposed scheme in terms of transmission rates.