Metasurface-based electromagnetic structure for electromagnetic absorption and radiation application

Abstract

In this paper, a metasurface (MS)-based multi-functional electromagnetic (EM) structure is proposed to realize its two different applications, namely absorption and radiation. The proposed structure is based on periodic arrays of disk-shaped metallic patches and split rings with four embedded lumped resistors. The metallic vias are inserted from top to bottom to connect the disk-shaped patches with a feeding network designed on the bottom layer where two p-i-n switches are embedded in the feeding network to alter the different functions of the proposed structure. For free space incident plan wave, the designed structure works as an absorber when the p-i-n switches are switched OFF. The absorber operates over a frequency band from 6.2 GHz to 8.2 GHz and unchanged over an incident angle from 0° to 30° for both TE and TM polarized incident waves. The same structure also works as a low scattering and high gain radiator when the p-i-n switches are turned ON and radiate within absorbing frequency band, i.e. from 7.5 to 8.0 GHz. The designed structure is fabricated and experimentally verified for EM absorption and radiation applications.

A low-profile coding metasurface for broadband radar cross section reduction via beam diffusion and absorption

“…Metasurface is a two-dimensional planar structure composed of periodic units, which has powerful ability to regulate electromagnetic (EM) waves [6][7][8]. RCS reduction based on metasurfaces has made great progress [9][10][11][12][13]. They mainly achieve RCS reduction through the absorption and diffusion of EM waves.…”

“…They mainly achieve RCS reduction through the absorption and diffusion of EM waves. For absorption metasurfaces, researchers achieve RCS reduction by designing resonant units or loading resistive media such as resistors [10], ITO films [14], carbon resistive films [15], etc However, this method faces shortcomings such as narrow operating bandwidth, low efficiency, and thick profiles. At the same time, a lot of efforts have been made to reduce RCS by beam diffusion [16][17][18][19][20].…”