Challenges and Opportunities of Amplified Information Metasurfaces for Simultaneous Wireless Communications and Power Transfers

In this paper, we summarized and pointed out the main challenges and opportunities in the design of amplified information metasurfaces for simultaneous wireless information and power transfer (SWIPT), such as instability, maximum output power, and operating bandwidth. Maximum output power and operating bandwidth directly determine the wireless charging distance and communication rates. And instability problems will break down the system. A scattering model is proposed to analyze these challenges. The instability is mainly due to the positive feedback of the power amplifier integrated with the element. Moreover, based on the scattering model and loadpull theory, the impedance of the amplifier is modeled for achieving its optimum performance including maximum output power and operating bandwidth.