Title :
Tracking load to optimize power efficiency in RF to DC rectifier circuits
Author :
Dehghani, Soroush ; Abbasian, Sadegh ; Johnson, Thomas
Author_Institution :
Sch. of Eng., Univ. of British Columbia, Kelowna, BC, Canada
Abstract :
A tracking load circuit for RF rectifiers is described. The tracking load is designed to maximize RF to DC conversion efficiency as the RF input power to the rectifier changes. The circuit consists of two DC to DC converters with two control loops. The duty cycle of the first stage converter is adjusted by an analog control loop to have an input impedance that is optimum for maximizing the power efficiency of the RF rectifier. A second stage converter, either a classical boost or buck converter, converts the fluctuating voltage from the first stage to a regulated output voltage. The application of the tracking load is illustrated with experimental results for a CMOS class D rectifier and a 10 W class F GaN RF rectifier.
Keywords :
CMOS integrated circuits; gallium compounds; maximum power point trackers; optimisation; rectifying circuits; CMOS class D rectifier; DC-DC converter; RF to DC conversion efficiency; RF to DC rectifier circuit; analog control loop; boost converter; buck converter; class F GaN RF rectifier; duty cycle; power 10 W; power efficiency maximization; power efficiency optimisation; tracking load circuit; CMOS integrated circuits; Energy harvesting; Load modeling; Maximum power point trackers; Radio frequency; Resistance; Voltage control; CMOS class D rectifier; RF rectifiers; class F rectifier; maximum power point tracking;
Conference_Titel :
Wireless Power Transfer Conference (WPTC), 2015 IEEE
Conference_Location :
Boulder, CO
DOI :
10.1109/WPT.2015.7140165
