RF Energy Harvesting–Aided IoT Network: System Design and Prototype Implementation

As more and more Internet of Things (IoT) devices are widely deployed, the issue of energy supply for these devices is becoming increasingly prominent. Considering not only the wireless information transfer (WIT) function of traditional IoT networks but also the characteristics of wireless power transfer (WPT), an RF energy harvesting-aided IoT network is proposed in this paper. In the new IoT network, a WPT transmitter and a WPT receiver are, respectively, introduced to the new gateway and the new end-device. A WPT transmitter is mainly composed of an antenna selection circuit, a power amplifier, and a directional antenna. A WPT receiver consists of a directional antenna, a matching network, a rectification circuit, and an energy management circuit. In order to coordinate WPT and WIT in an orderly manner and minimize WPT's interference on WIT, a time-division scheme is adopted. The proposed new IoT network aims to offer a new IoT scheme combining both WIT and WPT technologies. In addition, IoT devices can obtain a new energy supply through RF energy harvesting. Both the effectiveness and efficiency of the proposed RF energy harvesting-aided IoT network have been validated through experimentation.