Open AccessKa‐band multi‐focus and pattern manipulation in near‐field based on three‐dimensional printed transmit‐array antenna
Author(s) -
Liu Shi Lin,
Lin Xian Qi,
Zhu Zhong Bo
Publication year - 2020
Publication title -
iet microwaves, antennas and propagation
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.555
H-Index - 69
eISSN - 1751-8733
pISSN - 1751-8725
DOI - 10.1049/iet-map.2019.0651
Subject(s) - superposition principle , focus (optics) , aperture (computer memory) , near and far field , antenna (radio) , computer science , electronic engineering , antenna aperture , optics , focal point , radiation pattern , engineering , acoustics , telecommunications , physics , cardinal point , quantum mechanics
A simple method to achieve multi‐focus and pattern manipulation in antenna near field (NF) is proposed in this study, whose effectiveness is then validated by measurements based on different transmit‐array antennas. The radiating aperture is divided into several regions and each region corresponds to one assigned focal point, thus achieving multi‐focusing performance. Then, the superposition principle is employed and constrains the multiple foci into a certain area to get a contoured pattern. Three examples are investigated. Ant‐A presents four balanced focal spots simultaneously, while Ant‐B presents two unbalanced foci. A square flat‐top field pattern is obtained for Ant‐C. Three‐dimensional printing technology is employed to fabricate these lenses, resulting in a low cost and light weight. Measured results coincide well with the numerical design and simulation. The proposed method provides a simple and effective alternative for NF power redistribution and owns great value in such applications as radio‐frequency identification, wireless power transmission, millimetre‐wave imaging etc.