Multiband printed rectenna for radio frequency energy harvesting (RF-EH)

The growing demand for renewable energy has spurred significant interest in radio frequency (RF) energy harvesting as a sustainable method to power wireless devices. This paper presents a novel multiband monopole rectenna design for efficient RF energy harvesting across key wireless communication bands, including 900 MHz to 2.1 GHz (GSM/GPRS), 4.5 GHz (WiMAX), and 7 GHz (lower 5G). The antenna and rectifier are simulated in CST Studio and fabricated on a low-cost FR4 substrate. The monopole antenna exhibits strong resonances at 900 MHz, 4.5 GHz, and 7 GHz, with − 10 dB impedance bandwidths of 90, 7, and 21%, respectively, demonstrating robust impedance matching. Both simulated and measured reflection coefficients align with performance standards for WLAN, GSM/GPRS, and WiMAX applications. A key innovation of this work is the integration of a unified matching circuit that optimizes DC power conversion efficiency across multiple bands, simplifying the system architecture. The rectifier employs a Schottky diode with a low junction potential (0.34 mV) and a breakdown voltage of 2 V, striking an optimal balance between high power conversion efficiency and wideband operation. This design advances RF energy harvesting technology, offering a scalable and energy-efficient solution for next-generation wireless systems.