Combined RF-Ultrasonic Wireless Powering System for Sensor Applications in Harsh Environment

Sensors are vital tools in monitoring operating conditions and collecting data in scientific studies and engineering works. However powering sensors for a long term in harsh environments where physical access is difficult like enclosed oil pipes, sealed containers and underwater isn’t straightforward. To solve this problem, a novel hybrid power supply technique is proposed, combining the advantages of radio frequency and ultrasonic power transmission. By harnessing the penetration capabilities of ultrasound and the long-distance wireless transmission benefits of electromagnetic waves, the proposed a combined RF and ultrasonic wireless powering (CRUWP) system to power sensors deployed in harsh environments. This article builds a system model and introduces 90% efficient time-sharing energy management scheme for coupled circuits to address the power density mismatch between RF and ultrasonic energy transmission. Furthermore, the power budget analysis is presented for the hybrid power supply scheme, showcasing its capability to deliver 1 mW output power to the load.