Fairness-Based Multiuser Scheduling for Ambient Backscatter Communication Systems

This letter investigates and analyzes multiuser scheduling for ambient backscatter (AmBack) communication systems by taking the fairness issue into account. In contrast to traditional absolute signal-to-noise ratio (SNR)-based scheduling, proportional fairness (PF)-based scheduling is proposed to achieve the PF among AmBack users. Since it is not amendable to a closed-form expression for the outage performance, the asymptotic performance is derived to analyze the multiuser diversity order. For comparison, the cumulative distribution function (CDF)-based scheduling is also considered, where the fair channel access ratio (CAR) for AmBack users can be guaranteed. Simulation results confirm the correctness of analytical results, and demonstrate the effectiveness of the proposed scheduling schemes.