Low RCS Dual-Polarized Crossed Dipole Antenna Co-Designed With Absorptive Frequency- Selective Reflection Structure

Abstract

This article proposes a novel strategy for realizing a reduction in radar cross-section (RCS) of dual-polarized crossed dipole antenna. At first, a compact and polarization-insensitive absorptive frequency-selective reflection (AFSR) structure is proposed by incorporating a bandstop ring resonator within the circular-cross based broadband absorber. The bandstop ring resonator is designed on the backside of the resistive layer due to which a reflection window is realized at a frequency of 8.2 GHz between the two broadband absorptions (4.2–7.0 GHz and 9.2–11.5 GHz). A dual-polarized crossed dipole antenna is designed with operating frequency lying within the reflecting notch of the AFSR structure. A 6 × 6 AFSR structure array is truncated at the center where from which the crossed dipole is connected through a feed substrate. The AFSR structure enacts as a modified ground plane to the crossed dipole antenna. The proposed AFSR integrated antenna achieves an average mono-static RCS reduction of 12.51 dB and 12.62 dB for the TE and TM incident waves, respectively. Further, the AFSR based antenna is also measured for the bi-static RCS, wherefrom the average total RCS reduction of 80% for TE and TM incidence is attained in the frequency band of 4.2 to 11.5 GHz.

Keywords

• Absorptive frequency-selective reflection
• frequency-selective surface
• polarization-insensitive