A Fully Integrated CMOS Tri-Band Ambient RF Energy Harvesting System for IoT Devices
Jack Kee Yong, Wen Xun Lian, Harikrishnan Ramiah, Kishore Kumar Pakkirisami Churchill, Gabriel Chong, Nai Shyan Lai, Yong Chen, Pui‐In Mak, Rui P. Martins
Abstract
This article presents a fully integrated tri-band RF energy harvesting system (RFEH) in 65-nm CMOS technology. The system is designed to harvest ambient RF energies at 900 MHz, 1.9 GHz, and 2.4 GHz through a tri-band impedance matching network (IMN), cross-coupled differential-drive (CCDD) rectifier, and an output voltage monitoring circuit to limit the rectified output voltage to 3.3 V. The system achieves a power conversion efficiency (PCE) of over 30 % across all three frequency bands with a peak of 42.8 %. Furthermore, the system exhibits a peak sensitivity of -20 dBm at an output DC voltage of 1 <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$V$ </tex-math></inline-formula> output.