An efficient reflective polarization rotation meta surface for broadband RCS reduction

Abstract

A compact and broadband reflective polarization rotation meta surface (PRMS) with high polarization conversion ratio (PCR) and radar cross section (RCS) reduction is proposed. A linearly polarized incident electromagnetic (EM) wave is reflected with 90° polarization rotation using the proposed PRMS. The reflective PRMS unit cell consists of complementary stacked quasi fractal patch along with logarithmic stepped patch. This reflective PRMS is printed on stacked FR4 substrates covered by FR4 superstrate and is backed by a ground plane. The patches are connected to the metallic ground using non symmetric metallic vias and the overall dimension of the unit cell in terms of its minimum operating wavelength is only 0.088λ0 × 0.088λ0 × 0.082λ0. A polarization bandwidth of 97.69% with a maximum PCR of 99% is achieved. Further, the proposed reflective PRMS is arranged periodically in a checkerboard surface to obtain a broadband RCS reduction of 10 dB in the required band. A prototype of the checkerboard surface is fabricated and tested for the validation of simulation results. A good pact is obtained between the simulation and experimental results.

A Multiband and Multifunctional Metasurface for Linear and Circular Polarization Conversion in Reflection Modes

“…The birefringence effect, in naturally available crystals, divides the electric field vector into two orthogonal components [6]. Another way to obtain polarization conversion is molecular chirality (optical activity) [7]. These devices are not very useful in sub-miniaturized applications due to their bulky volume, limited bandwidth, high loss, and incident angle-dependent response.…”

Broadband linear‐cross and circular‐circular polarizers with minimal bandwidth reduction at higher oblique angles for RCS applications

“…Dividing the electric field vector into two orthogonal components referred to as birefringence effect in naturally available crystals 5 . Molecular chirality (optical activity) is the other way to obtain polarization conversion 6 . These devices are bulky in volume, narrow bandwidth, high loss and incident angle‐dependent response is limiting its practical usage in sub‐miniaturized applications.…”

Broadband RCS reduction for both microstrip array and Fabry‐Perot antenna based on the quasi‐ AMC superstrate

“…However, it usually suffers from narrow bandwidth and high cost. For the passive cancelation, the traditional methods often include surface reshaping, 3,4 and radar absorbing materials (RAMs) 5,6 . The former method changes the shape of targets to deflect the scattered waves away from the radar, and the latter one converts the electromagnetic (EM) waves into heat by loading lossy resistance.…”

“…However, the losses introduced by these elements may decrease the radiation efficiency. Additionally, several lossless units were also utilized to form the superstrate, for example, coding metasurface, 13 frequency selective surface (FSS), 14‐16 and polarization conversion metasurface (PCM) 5,17‐19 . In Zhang et al, 13 a 2‐bit coding metasurface was utilized to achieve a wideband RCSR while the 3‐dB gain bandwidth was narrow.…”