A Frequency Selective Radome With Wideband Absorbing Properties

TLDR

The paper presents a frequency selective radome that functions as a pass‑band filter at a specified frequency band while acting as an absorber above the transmission band. The radome employs a metallic frequency‑selective surface of interdigitated Jerusalem cross elements as a ground plane for a thin, wideband absorber built from resistive high‑impedance surfaces, and its performance is validated through equivalent‑circuit modeling and full‑wave simulations. The outer absorber effectively reduces the antenna system’s signature when illuminated by out‑of‑band signals.

Abstract

A frequency selective radome is presented, acting as a pass band filter at a given frequency band, while behaving as an absorber above the transmission band. The pass band behavior is obtained by a metallic FSS realized through a compact interdigitated Jerusalem cross element characterized by a very large rejection band. The metallic FSS is used as the ground plane of a thin wideband absorber based on resistive high-impedance surfaces within the total reflection band. The outer absorber reduces the signature of the antenna system when the radome is illuminated by out of band signals. The resistive FSS which comprises the absorber is designed so to minimize losses within the transmitting band of the radome. The composite structure is thoroughly analyzed by an efficient equivalent circuit approach and by full-wave numerical simulations.