A Broadband Low-RCS Antenna Based on Hybrid Mechanism Metasurface

In this letter, a novel broadband low radar cross section (RCS) antenna is proposed based on the hybrid mechanism metasurface of the Panchartnam–Berry (PB) phase and absorption. The proposed structure is composed of two layers separated by an air spacer, where the upper layer is a resistive sheet with high-frequency passband, and an integrated PB metasurface with radiation and scattering properties serves as the lower layer. The combined function of the resistive layer and PB metasurface realizes the broadband RCS reduction (RCSR) of low-frequency absorption and high-frequency scattering. The PB unit cells with different rotation angles directly multiplexed form a PB antenna to realize the broadside radiation by loading the feeding network. A 2 × 2 array prototype is fabricated, and the experiment verifies the effectiveness of the proposed PB antenna. The measured and simulated results show that the realized gain of the PB antenna array reaches 21.1 dB at 9.8 GHz, and the average RCSR of the monostatic is about 8.3 dB from 2 to 13 GHz under x - and y -polarized normal incidence waves.