Open AccessDual‐mode charge pump with second‐harmonic readout for antenna alignment in wireless power transfer system
Author(s) -
Zhang Hao,
Guo YongXin,
Wu Wen
Publication year - 2019
Publication title -
electronics letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.375
H-Index - 146
eISSN - 1350-911X
pISSN - 0013-5194
DOI - 10.1049/el.2018.6572
Subject(s) - harmonics , harmonic , rectification , electrical engineering , wireless power transfer , radio frequency , voltage , antenna (radio) , charge pump , power (physics) , energy conversion efficiency , rf power amplifier , physics , engineering , electronic engineering , amplifier , acoustics , capacitor , electromagnetic coil , cmos , quantum mechanics
A charge pump is presented by integrating two identical voltage doublers and a modified rat‐race coupler to enable its dual‐mode operations: radio‐frequency (RF)‐to‐direct current (dc) power conversion and second‐harmonic readout. Due to the property of the modified rat‐race coupler, it is able to differentially divide incident RF signals for successive voltage doublers’ high‐efficiency rectification, and couple second harmonics for readout in two highly isolated channels. Output dc voltages are combined in parallel on a single load resistance for more practicality. Experimental validations are demonstrated by both simulation and measurement with a maximum RF‐to‐dc power conversion efficiency of 71.3% and −14.2 dBm second‐harmonic generation with an incident signal power of 19 dBm. This dual‐mode charge pump brings a prospect for antenna alignment in the wireless power transfer system by further exploiting second harmonics.