An Ambient RF Energy Powered Wireless Sensor Node for Environmental Monitoring

ABSTRACT

With the rapid proliferation of Internet of Things (IoT) devices and advancements in low‐power technologies, radio frequency (RF) energy harvesters present an economical and convenient power solution for low‐power wireless sensor nodes (WSNs). The limited utilization of ambient energy in current RF self‐powered WSNs is primarily due to inadequate spectrum coverage. This research proposes an ambient RF energy powered WSN to monitor environmental temperature, humidity, and atmospheric pressure. An integrated broadband Vivaldi rectenna has been developed to harvest RF energy across the 1.8 to 2.45 GHz range, utilizing an impedance matching network (IMN) based on conjugate‐complex techniques alongside a tuning network that collaboratively enhances broadband rectification. The maximum power conversion efficiency (PCE) of the rectifier reaches 61% at an input level of 0 dBm. The system demonstrates sustainable operation at a distance of 16.15 m from a directional RF source. These remarkable results underscore the promising potential of the proposed system as a self‐sustainable and cost‐effective solution for IoT applications with low power requirements.