Design of Wideband Beamforming Metasurface With Alternate Absorption

Abstract

In this paper, we propose a periodic structure that is capable of alternating between absorption and radiation mode. The designed periodic structure consists of an array of 6×6 square shaped unit cell. Each unit cell consists of a multi-layered structure, with dimensions of 0.5λ×0.5λ. The resonators are placed on the top layer and the feeding network is designed and implemented on the bottom layer. The ground layer is sandwiched between the two dielectric substrates. All resonators are connected to a 50 feed-line using the corporate feeding technique. To achieve broadband absorption, lumped resistors are inserted into the resonators. The proposed metasurface structure achieves broadband radiation, with low RCS and high gain, in the propagation direction whereas broadband absorption is achieved, when it is exposed to a free space plane wave. Moreover, the metamaterial absorber has stable absorptivity for an incident angle of (0 •-30 •). To verify the in-band absorption and radiation of the proposed design, a 6×6 periodic array of resonators has been fabricated and experimentally verified in an anechoic chamber. The measured results validate the performed simulations.

A Comprehensive Review of Metasurface Structures Suitable for RF Energy Harvesting

“…The boundary conditions depend on the continuous tangential components of electric and magnetic fields across an interface between two dielectric media. Due to their rich EM field manipulation capabilities, metasurfaces could enable many incredible applications in the field of optics and nanophotonics, such as shielding [74]- [76], EH [57], [77]- [83], antennas [84]- [86], radomes, etc.…”

High gain, low radar cross‐section, and left hand circularly polarized antenna array based on metamaterial inspired elements

“…Reshaping the antenna radiator is another way to reduce the RCS of the antenna, 3 mostly the metamaterial absorber was used to absorb the detection energy. [4][5][6][7][8][9][10][11][12] The dendritic shape perfect metamaterial absorber has been integrated into an antenna for RCS reduction. 4 The designed metamaterial absorber has been loaded around the patch antenna that can absorb the incoming energy, where the narrowband operation was its limitation, however, the radiation characteristics of the original antenna were almost preserved.…”

“…In References 1 and 2, the observability of the antenna was reduced by loading the radar absorbing materials around the antenna, which is an effective method to absorb the detection energy and further loss by heat. Reshaping the antenna radiator is another way to reduce the RCS of the antenna, 3 mostly the metamaterial absorber was used to absorb the detection energy 4‐12 . The dendritic shape perfect metamaterial absorber has been integrated into an antenna for RCS reduction 4 .…”

All-Dielectric Transparent Metamaterial Absorber With Encapsulated Water

“…In the past several years, metamaterial absorbers have rapidly developed owing to their ability to customize the frequency-dependent absorptivity and emissivity and to provide a more diversified absorption performance. Metamaterial absorbers have many potential applications for energy harvesting, radar stealth, and electromagnetic compatibility [1]- [6], Most of the present metamaterial absorbers have three-layer configurations consisting of a dielectric spacer and two separating metal layers. One or both of the metal layers are made of periodically patterned resonators [7]- [13].…”