Channel-Dependent Scheduling in Wireless Energy Transfer for Mobile Devices

Resonant Beam Charging (RBC) is a long-range, high-power, mobile, and safe Wireless Energy Transfer (WET) technology, which can provide wireless power for mobile devices like Wi-Fi communications. Due to the wireless energy transmission decay in RBC systems, the charging power received per device relies on the distance-dependent energy transmission channel. To extend battery life of all devices, this paper develops a Channel-Dependent Charge (CDC) scheduling algorithm to control receivers' charging power, order and duration. Each receiver is assigned a dynamic scheduling coefficient, which is the product of the battery's remaining energy and the energy transmission channel. The resultant optimal charging order is to charge the receiver with the minimum scheduling coefficient first per equal unit-length time slot. It is shown analytically and experimentally that the CDC algorithm achieves higher charging performance than other scheduling algorithms including the Round-Robin Charge (RRC) scheduling algorithms. In a word, the CDC scheduling algorithm offers a viable approach to extending mobile devices' battery life while accounting for varying RBC transmission channels.