Design and Implementation of a Quasi Nondiffraction Beam for Microwave Power Transmission Application

In this letter, a quasi nondiffraction beam is designed and implemented for microwave power transmission (MPT) application. To generate a quasi nondiffraction beam, a new formula is derived to calculate the phase distribution on the metasurface (MS), and a phase shifting unit with 360° transmission phase coverage and transmission amplitude better than −3 dB is designed to achieve desired phase. The simulated and measured results demonstrate that a quasi nondiffraction beam can be generated by the proposed MS. In order to prove that the quasi-nondiffraction beam can be used for microwave power transfer, a miniaturized MPT system is built and measured. The system-level measurement results indicate that the proposed transmitting antenna helps the receiving terminal to harvest more power and improves the power transmission efficiency of the system.