Metasurface-Based Cylindrical Lenses and Their Antenna Gain Enhancement

Abstract EN

Electromagnetic metasurface lenses with the characteristic of being conformal to a cylindrical geometry are presented in this study.

Based on the formulated principle of the cylindrical metasurface lens operating with transmission or reflection mode, the transmission or reflection phase gradient varying along the circumferential direction of a cylinder is implemented.

A focused beam is observed at the objective focal point for each lens illuminated by a plane electromagnetic wave with transverse magnetic or transverse electric polarization.

A coaxial-fed microstrip patch antenna element is used as a feeding of cylindrical metasurface lenses and positioned at their focal points, so as to evaluate their application in the enhancement of antenna gain along the boresight direction.

By virtue of the focusing ability of presented lenses, effectively enhanced boresight gain from the cylindrical metasurface lens antennas are obtained, in comparison with the freestanding feeding antenna.

The agreement between simulation and measurement validates the designs.

Conformal integration or embedment of the electromagnetic lens into a certain platform skin with cylindrical characteristics is therefore potentially demonstrated, which implies an enhancement of boresight gain without obviously disturbing the local shape of the skin by apparent weight or drag.