An Ultra-Wideband Circular Polarization-Maintaining Metasurface and Its Application in RCS Reduction

Abstract

In this work, a circular polarized (CP) maintaining metasurface is proposed, which can realized ultra-wideband CP-maintaining reflection and make its co-polarization reflection coefficient under CP incidence close to 1.0 in the frequency range from 6.2 to 26.4 GHz. Because Pancharatnam-Berry (PB) phase can be generated in the co-polarized reflection coefficient under CP incidence by rotating its unit cell structure, a 2-bit PB coding metasurface for Radar Cross Section (RCS) reduction is further proposed based on the CP-maintaining metasurface. The simulated results show that the proposed PB coding metasurface has excellent performance in RCS reduction, compared with a pure metal plate with the same size, its RCS can be reduced more than10dB under arbitrary polarization normal incidences in the ultra-wide frequency band 6.2-26.5GHz with relative band of 124.1%. Finally, an effective experimental validation is carried out.

Multiple-Beam Steering Using Graphene-Based Coding Metasurfaces

“…The methodology of the coding beam reconfiguration needs a stable amplitude response and periodic gradient phase shifts in the range of 0–2π [ 13 , 14 , 15 , 16 ]. Conventional metallic MS form phase differences by changing the sizes [ 13 ], orientations [ 14 , 15 , 16 ], or shapes [ 5 , 10 ] of the unit cells. Particularly, encoding two types of unit cells with 0 and π phase responses as “0” and “1” elements can realize a 1-bit coding MS [ 8 , 9 ].…”

Arbitrary polarization angle and wavefront manipulation of linearly polarized waves using PB phase

“…As for EM wavefront manipulations, PB phases and resonant phases have been applied to realize desired phase distributions on MS apertures to generate certain shaped beams [17][18][19][20][21][22][23][24][25]. MSs designed based on resonant phases generally have a limited frequency bandwidth.…”

“…In [19], a reflective MS using resonant phases was designed to generate a vortex wave at a single frequency. PB phase has attracted more attentions due to its characteristics of wideband and convenient phase control by tuning the azimuth angle of unit cells [21]. MSs designed based on PB phase have been used to achieve radar cross section (RCS) reduction, focusing, anomalous reflection, and imaging [21][22][23][24][25].…”

“…PB phase has attracted more attentions due to its characteristics of wideband and convenient phase control by tuning the azimuth angle of unit cells [21]. MSs designed based on PB phase have been used to achieve radar cross section (RCS) reduction, focusing, anomalous reflection, and imaging [21][22][23][24][25]. In [21], an ultra-wideband MS designed based on PB phases was proposed to achieve RCS reductions.…”

“…MSs designed based on PB phase have been used to achieve radar cross section (RCS) reduction, focusing, anomalous reflection, and imaging [21][22][23][24][25]. In [21], an ultra-wideband MS designed based on PB phases was proposed to achieve RCS reductions. However, PB phase based MSs designed in previous works can only achieve circularly polarized (CP) wavefronts control, and the beams generated by such MSs were also CP.…”