Realization of Single-Layer Fourier Phased Metasurfaces for Wideband RCS Reduction

Abstract

An efficient and fast strategy to design and realize single layer Fourier phased metasurfaces for wideband radar cross section (RCS) reduction when illuminated by a circular polarization (CP) plane wave is proposed in this letter. The scattering phase (between 0 o and 360 o ) required at each unit cell of the proposed metasurfaces was computed using the Fourier phase formula in which the focal length (F) is inversely proportional to the phase distribution. Pancharatnam-Berry (PB) phase theory was applied with unit cells of subwavelength periodicity to further enhance the scattering and RCS reduction characteristics. The proposed wideband Fourier phased metasurface has a square shape and contains 30 × 30 PB unit cells with subwavelength periodicity of 5 mm ≈ 0.26λ16GHz. Both simulation and measured results show that the proposed Fourier phased metasurfaces can achieve more than 10 dB of RCS reduction under normal incidence of CP plane wave regardless of the value of F. Under oblique incidence, more than 10 dB of RCS reduction was maintained for incident angles up to 60°. In addition, the single-layer Fourier phased metasurface features wideband 10 dB RCS reduction bandwidth from 10 GHz to 24 GHz with a thickness of only 2 mm. This resulted in an 82.3% fractional bandwidth (FBW) of RCS reduction which is higher than other designs reported in the literature. The proposed design strategy provides a promising way to design and realize metasurfaces for wideband and stable RCS reduction performance without the need to use a computationally complex and/or time-consuming and slow running optimization algorithm.

Terahertz VO2-Based Dynamic Coding Metasurface for Dual-Polarized, Dual-Band, and Wide-Angle RCS Reduction

“…This research introduces complex multilayer structures to reduce RCS and enhance the gain of the meta-antenna. Some of the studies work on realizing a simple structured RCS reduction metasurface [ 3 , 11 , 12 ]. Some research further optimizes the metasurface using the particle swarm optimization (PSO) algorithm, genetic algorithm (GA), and pseudorandom algorithm [ 13 , 14 , 15 ].…”

Broadband Double Layer Metamaterial Circular Polarizer Based on H-Spiral Structure

“…Additionally, the circular polarizer based on FTLP wave and new structure is introduced based on chiral metasurface (CCMS) to achieve a significant asymmetric transmission effect [16][17]. The metasurface (MS) is a wellknown competitor in this race and a feature that has attracted a lot of interest because of their low profile and remarkable electromagnetic (EM) manipulation properties [18][19]. The different approaches of polarization transmission based on MS had been proposed such as reflected crossed conversion of polarization at linear or circular polarized (CP) incidence [20], reflecting and transmissive LP conversion at LP incidence and an ultrathin wideband metasurface structure is proposed for X-band applications [21][22], as well as transmissive cross-polarization conversion at CP or LP incidence.…”

Design of Polarization-Insensitive and Angularly Stable Metasurfaces With Symmetric Cubic Phase Distribution for Broadband RCS Reduction

“…However, all Chessboard-like metasurfaces exhibit similar scattering behavior of reduced boresight scattering, but with four lobes of intense scattering in the diagonal planes, which can be easily detected by bistatic radar sensors [11]. Coding metasurfaces including 1bit, 2-bit, 3-bit, and multi-bits [12] - [15], were introduced to reduce RCS and guarantee a low-level diffuse scattering in all directions without strong scattering lobes in any direction which helps in making it very hard to be detected by both monostatic and bistatic radars [16] - [19]. Despite the amazing RCS reduction characteristics of the random coding metasurfaces, they lack a phase design formula to calculate the optimum random phase distribution required for wideband RCS reduction.…”