Wideband radar cross section reduction of a circularly polarized antenna using polarization conversion metasurfaces

Abstract

In this study, a technique for designing a compact and low radar cross section (RCS) circularly polarized (CP) antenna is proposed. The designed CP antenna resonates at 8.7 GHz. The circular polarization is achieved by trimming opposite corners of the square patch and etching out thin slots. A new method is used to keep the radiation performance well preserved and to reduce the RCS of the CP antenna by employing polarization conversion metasurfaces. The PCM comprises double‐head arrow elements arranged around the CP antenna in four quadrants. Wideband monostatic RCS reduction is achieved for frequencies from 8.0 to 20 GHz. The experimental results verify the simulated ones, and also, the performance parameters such are realized gain, impedance bandwidth, axial ratio, and radiation pattern are well preserved after loading polarization conversion metasurface.

A low-profile wideband dual-polarized antenna with nonuniform metasurface

“…For example, the reference antenna in [10,11,12,13]. In order to reduce the height of the antenna and enhance other features, metasurface is introduced into the antenna design [14,15].…”

Wideband monostatic and bistatic radar cross‐section reductions using polarization conversion metasurface

“…In addition to polarization regulation of EM waves, polarization conversion metasurface (PCM) can be used for RCS reduction by arranging the array and its mirror array. In Refs., [11][12][13][14][15][16][17] only one PCM unit was designed and obvious RCS reductions were achieved in broadband. It's worth noting that the results of RCS reduction depend on the performances of unit cell.…”

“…18,19 Up to now, there are still a lot of space to improve conversion bandwidth and efficiency of PCM. Moreover, many research 6,8,9,12,14,[16][17][18]20 mainly focus on monostatic RCS under normal incidence, those are lacking analyses and evaluations for bistatic RCS or oblique incidence. In the actual application, EM waves cannot only vertically impinge when radar detects target objects.…”

“…In this work, a novel PCM is proposed, which can realize cross-polarization conversion in a wide range from 13.9 to 30.3 GHz with polarization conversion ratio (PCR) higher than 97%, covering K-band. Compared with the similar cross-PCM, 1,11,12,19 this structure has wider conversion bandwidth and higher PCR. A low-RCS antenna is designed and fabricated by a CP antenna loaded with the proposed PCM units.…”