Co-Designed Phased Array with HPM Protection, Wideband Stealth and Wide-Angle Beam-Scanning

In this paper, a co-designed multi-functional phased array is proposed with high-power microwave (HPM) protection, wideband stealth and wide-angle beam-scanning abilities. A universal two-port equivalent circuit model (ECM), including different incident powers and polarizations, is analyzed to elucidate the inherent physical mechanisms. For low-power microwave (LPM) incidence, the proposed design has a high-efficiency transmission window adjacent to two wide absorption bands independent of the incident polarization. As the incident power increases, the co-designed phased array exhibits a nonlinear transmission response. For HPM incidence scenarios, regardless of the polarization, the transmission band disappears and converts to an absorption band. When the feeding ports of the co-designed phased array are excited, wide-angle beam-scanning can be acquired. An 8 × 8 co-designed phased array prototype is fabricated and measured in the far-field microwave anechoic chamber for demonstrating its scattering and radiation functions. The measured 10 dB radar cross section (RCS) reduction of the co-designed integrated phased array is from 2.22 to 7.29 GHz under co-polarized LPM incidence, as well as from 2.3 to 3.64 GHz and 3.95 to 6.66 GHz under cross-polarized LPM incidence. The measured radiation pattern can scan within -50° to 50° with stable beam shapes and low sidelobe levels. For nonlinear performance, a 2 × 1 energy selective surface (ESS) prototype is fabricated and measured in a rectangular waveguide. The measured results show that the proposed ESS can distinguish the power level of the incident signal and provide adaptive protection when the incident intensity gradually increases from LPM to HPM. The consistency of theoretical, simulation, and measured results verifies the effectiveness of the proposed ECM and design.