A novel broadband l inear‐cross and l inear‐circular reflective polarizer based on interdigital capacitance loaded dipole for radar cross‐section applications

Abstract

A novel interdigital capacitance (IDC) frequency selective surface (FSS) based linear-cross reflective polarizer for K-and Ka-band applications is demonstrated in this work. The suggested device includes an IDC-loaded dipole printed on a thin FR-4 grounded dielectric substrate. From 17.02 to 37.30 GHz, it shows linear-cross conversion with a minimum 90% polarization conversion ratio (PCR) of 20.28 GHz bandwidth (74.7% fractional bandwidth [FBW]) for a y/x polarized incident electromagnetic (EM) wave. Along with linear-cross conversion, this polarizer also performs linear-circular conversions with axial ratio ≤ 3 dB in two frequency bands (Ku band-right circular, 15.13-16.15 GHz; Ka-band-left circular, 38.52-39.78 GHz) with 6.52%, and 3.14% FBW, respectively. The design performance is stable up to 45 for both transverse electric (TE) and transverse magnetic (TM) modes. The polarizer unitcell has structural dimensions 0.177 Â 0.177 Â 0.061λ 3 L , where λ L corresponds to the freespace wavelength of the lowest working frequency. The polariser's transmission line equivalent circuit model is extracted, and a good match is observed with the EM solver response. The broadband behavior of FSS and the ground plane is better understood by looking at surface current patterns at resonant frequencies. The proposed design's radar cross-section (RCS) analysis is compared to perfect electric conductor for the bistatic condition. The design novelty lies in its compact architectural volume of the unitcell 1.911 λ 3 L =1000 À), low-profile, broadband PCR response with superior angle stability, dualpolarization conversion with circular rotation switching makes it a good option for real-time applications.

A wide-incidence-angle insensitive multi-polarization converter based on reflective metasurface

“…Figures 7(c Finally, the equivalent circuit of our polarization converter is also analyzed by referring literature [25]. Because the structure is symmetric along the u-and v-axis, only the lower left corner part is analyzed for the u-polarized, and the upper left corner part is analyzed for the v-polarized incident wave.…”