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.

中文翻译：

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用于微波功率传输应用的准无衍射光束的设计与实现


在这封信中，为微波功率传输（MPT）应用设计并实现了准无衍射光束。为了产生准无衍射光束，推导了一种新的公式来计算超表面（MS）上的相位分布，并设计了具有360°传输相位覆盖范围和传输幅度优于-3 dB的移相单元以实现所需的相位。模拟和测量结果表明，所提出的 MS 可以产生准非衍射光束。为了证明准无衍射光束可用于微波功率传输，搭建并测量了小型化MPT系统。系统级测量结果表明，所提出的发射天线有助于接收终端收集更多功率并提高系统的功率传输效率。