A Broadband RCS Reduction Metasurface With Dual Transmission Windows

This work proposes a frequency selective metasurface (FSM) with two transmission windows within the wideband radar cross section (RCS) reduction band. First, to achieve dual transmission windows, dual-band and triple-band artificial magnetic conductors are introduced as the two elements of the FSM. Second, the input reactance conditions of the two elements under the reduction condition are derived, and the circuit parameters are optimized to meet these conditions. Furthermore, the transmission and RCS reduction performance after arraying are analyzed based on array theory. Third, based on the corresponding equivalent circuit models, two dual-layer structural elements are designed and arranged in a checkerboard pattern. Finally, a metasurface prototype is fabricated and experimented with. The experimental results demonstrate that the proposed FSM exhibits a −10 dB RCS reduction from 4.2 GHz to 13.9 GHz and transmission windows with insertion losses of −1.45 dB at 7.3 GHz and −1.52 dB at 12.6 GHz.