  Resonant Beam Charging (RBC) is a promising Wireless Power Transfer (WPT)
technology to provide long-range, high-power, mobile and safe wireless power
for the Internet of Things (IoT) devices. The Point-to-Multipoint (PtMP) RBC
system can charge multiple receivers simultaneously similar to WiFi
communications. To guarantee the Quality of Charging Service (QoCS) for each
receiver and maximize the overall earning in the PtMP RBC service, we specify
the Charging Pricing Strategy (CPS) and develop the High Priority Charge (HPC)
scheduling algorithm to control the charging order and power allocation. Each
receiver is assigned a priority, which is updated dynamically based on its
State of Charging (SOC) and specified charging power. The receivers with high
priorities are scheduled to be charged in each time slot. We present the pseudo
code of the HPC algorithm based on quantifying the receiver's SOC, discharging
energy and various relevant parameters. Relying on simulation analysis, we
demonstrate that the HPC algorithm can achieve better QoCS and earning than the
Round-Robin Charge (RRC) scheduling algorithm. Based on the performance
evaluation, we illustrate that the methods to improve the PtMP RBC service are:
1) limiting the receiver number within a reasonable range and 2) prolonging the
charging duration as long as possible. In summary, the HPC scheduling algorithm
provides a practical strategy to maximize the earning of the PtMP RBC service
with each receiver's QoCS guarantee.
