It all started with a spark. Let us rewind back to 1887, in Germany. The days were getting cooler in the garden of the Technische Hochschule in Karlsruhe as Heinrich Rudolf Hertz was setting up the first-ever far-field wireless power transmission with increasingly more power [1]. He was striving to demonstrate the wireless nature of electromagnetic waves and propagation. Moreover, as no high-frequency (nearly 100 MHz) voltmeter was available at that time for his experiment, he had to transmit enough power to generate a spark-hundreds of volts!-at the receiver to validate the famous theory of James Clerk Maxwell.

中文翻译：

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回收环境射频能量：远场无线功率传输和谐波反向散射


这一切都是从一个火花开始的。让我们回到 1887 年的德国。当海因里希·鲁道夫·赫兹 (Heinrich Rudolf Hertz) 正在建立首个功率越来越大的远场无线电力传输 [1] 时，卡尔斯鲁厄理工学院的花园里的天气变得越来越凉爽。他致力于展示电磁波和传播的无线本质。此外，由于当时没有高频（近100 MHz）电压表可供他的实验使用，他必须传输足够的功率以在接收器处产生数百伏的火花！以验证詹姆斯·克拉克·麦克斯韦的著名理论。