Autor: |
Zhaobo Zhang, Chenchang Zhan, Man-Kay Law, Yang Jiang, Pui-In Mak, Rui P. Martins |
Jazyk: |
angličtina |
Rok vydání: |
2021 |
Předmět: |
|
Zdroj: |
IEEE Open Journal of Circuits and Systems, Vol 2, Pp 436-444 (2021) |
Druh dokumentu: |
article |
ISSN: |
2644-1225 |
DOI: |
10.1109/OJCAS.2021.3077621 |
Popis: |
This paper presents a dual-antenna energy harvesting (EH) system using full-energy extraction (FEE) to reduce the buffer capacitor requirement and improve the input power response speed. Instead of using large buffer capacitors (in the order of $\mu \text{F}$ ) at the rectifier output, the proposed FEE technique can efficiently harvest the incoming 915MHz radio-frequency (RF) energy using only a 1-nF capacitor per channel, while reducing the operating frequency of the subsequent DC-DC converter for power loss minimization. The two most popular RF rectifiers are investigated to relax the energy extraction degradation due to impedance mismatch. The boost DC-DC converter combines the harvested energy from the dual-inputs through the FEE controller. Fabricated in standard 0.18- $\mu \text{m}$ CMOS and wire-bonded on an FR4 PCB, the dual-antenna EH system with the DC-DC converter operating typically at 6.25kHz demonstrates a measured peak system efficiency of 75.2% at an output power of $22.6~\mu \text{W}$ using only two 1-nF buffer capacitors at 1- $\mu \text{F}$ load. With a significant buffer size reduction than prior art at similar efficiency/power level, a short startup time of ~ 45ms is achieved when the output rises from 0 to 1 V at $15.5~\mu \text{W}$ total rectifier output power, corresponding to 90% startup time reduction over the conventional approach. |
Databáze: |
Directory of Open Access Journals |
Externí odkaz: |
|