Wireless RF Energy Transfer: An Overview

Abstract

This chapter provides an overview of the main energy harvesting (EH) technologies and their relevant role in present and future internet of things (IoT) deployments. EH technologies for wireless machine-type devices can be mainly classified into the following two categories: ambient EH, and dedicated EH. The chapter emphasizes on RF–EH, and highlights its advantages compared to competing EH technologies reduced form-factor implementation and native multi-user support. RF–wireless energy transfer (WET) systems consist of three key components: RF transmitters, medium, and EH node. It focuses on the non-decreasing EH transfer function with the incident RF waveform power as sole input. The chapter describes the general architecture of an RF–EH IoT network, and the main layouts for wireless information transfer (WIT) and WET along with potential applications. WET, as a pivotal component of RF–EH networks, is fundamental for realizing the Internet of Energy paradigm.