Camouflaging a High‐Index Dielectric Scatterer with Buried Metasurfaces

Abstract

Metasurface‐tuning is presented as a solution to camouflage high‐index and electrically large dielectric parasitic scatterers. By incorporating metasurfaces into the dielectric volume of the scatterer, it is possible to reduce its scattering signature with respect to a given dielectric reference. The metasurface's surface impedance is retrieved analytically from a transmission‐line model and the induced field ratio parameter is introduced to characterize the scattering behavior of the scatterer. The scattering reduction effect achieved by the metasurfaces is validated with microwave near‐field full‐wave simulations and experiments for both normal and off‐normal transverse‐electric and transverse‐magnetic polarized incident wave illuminations. The study highlights the capability of metasurface‐tuning as a polarization‐insensitive and frequency‐adjustable solution to reduce spurious scattering from high‐index dielectric mechanical pieces such as seams in large ground‐based radio‐frequency antenna radomes.

Bi-layered coded metasurface for multi-functional hologram with broadband transmission and efficient reflection

“…As the two-dimensional counterpart of metamaterials [1] , metasurfaces circumvent the issues related to high loss and complex fabrication and allow the precise control of the amplitude [2][3][4] , phase [5] , and polarization [6] of electromagnetic waves, opening the door to interesting prospects. At present, metasurfaces have been proposed for a wide range of applications, such as perfect lens [7] , vortex beams [8] , camouflaging [9] , and image holograms [10][11][12][13][14][15] . So far, metasurface holograms have achieved rapid developments due to their applications in information encryptions and imaging displays [16,17] .…”

Full‐Space Double‐Layer Patterned 2‐Bit Coding Metasurface Hologram

“…Due to their unique electromagnetic features, they are able to show excellent capabilities in tailoring amplitude, phase and polarization of electromagnetic waves. In view of these intrinsic characteristics, numerous applications of metasurfaces have been reported, such as perfect lens, [7] anomalous reflection, [8,9] camouflaging, [10,11] vortex beam, [12,13] and hologram. [13][14][15][16][17][18][19][20][21][22][23][24][25] Compared to traditional hologram technologies, metasurface-based holograms present advantages of high spatial resolution, low noise, high precision, to name a few.…”