Powering Autonomous Sensors Using Radio Frequency Harvesting for IoT Applications

Abstract

The abundance of connected devices in modern cities and metropolises has contributed to the development of intelligent infrastructure and networks. More specifically, the integration of devices within the Internet of Things (IoT) has become integral to smart cities, enhancing various aspects such as safety, congestion management, and providing real-time information to users. However, the deployment of IoT networks relies on autonomous sensors capable of collecting and transmitting data in real-time to either other devices or centralized units. Having a reliable and non-stop power source to maintain the sensor operational 24/7 poses a challenge, that is why this paper will focus on analysing radio frequency harvesting, to create a continuous power output for the sensors. Mobile networks spectrums are preferred in our case due to the high-power density they offer, compared to other radio technologies. The RF (Radio Frequency) harvester circuit is built from several components, the Long-Term Evolution (LTE) band antenna, the coupler circuit, the rectifier circuit and the load, which in our case will be the sensor. Various circuit elements are evaluated and compared, addressing the requirements of output voltage and power. The findings from this research provide insights into the practicality of RF harvesting as a sustainable energy solution for autonomous sensors within IoT networks, paving the way in the evolving landscape of connected devices.