A Low-RCS Parabolic Reflector Antenna using Absorptive Frequency-Selective Reflector

This paper presents a parabolic reflector antenna using absorptive frequency-selective reflector (AFSR), resulting in both high-gain and low out-of-band radar cross-section (RCS) performance. The AFSR structure consists of two stepped-impedance resonators (SIRs) with lumped resistors, achieving a reflection band from 7.34 GHz to 8.47 GHz with two absorption bands from 2.5 GHz to 5.7 GHz and 9.4 GHz to 13.9 GHz, respectively. Based on the proposed AFSR structure, a parabolic reflector antenna prototype is designed, which exhibits a realized gain of 19.1 dB at 8 GHz, corresponding to an aperture efficiency of 43%. Meanwhile, the proposed structure achieves an out-of-band RCS reduction around 10 dBsm ranging from 2.7 GHz to 5.6 GHz and 9.7 GHz to 13.6 GHz, respectively.