Energy-Efficient and Wide-Angle Simultaneous Wireless Information and Power Transfer for Smart Energy System

초록

This paper presents an energy-efficient and wide-angle simultaneous wireless information and power transfer (SWIPT) system designed for smart energy systems, such as the Internet of Things (IoTs). The system transmits information by connecting numerous IoT devices to a network, while a microwave-based power grid eliminates the need for manual battery replacement. Although the dual functionality of SWIPT, a communication signal chain and a power transmission chain, offers convenience, it increases the number of components and overall power consumption. A new energy-efficient architecture is proposed that shares the highest power-consuming component, the power amplifier-across both signal chains. The operating principle and theoretical analysis of the proposed architecture are presented, and improved power efficiency is demonstrated, achieving a DC-to-RF efficiency of 31.4%, which is more than double that of conventional architectures. Furthermore, a wide-angle scanning array antenna is developed, achieving scan angles up to +/- 79 degrees in the xz-plane and +/- 75 degrees in the yz-plane. The simultaneous transmission of power and 64-QAM modulated information signals is experimentally verified, maintaining error vector magnitude (EVM) below 8% across various distances and angles. With its energy efficiency and wide-angle capabilities, the proposed SWIPT system presents a practical solution for managing large-scale, spatially distributed IoT devices.

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