Design, modelling, and validation of electrically tunable multifunctional composites with dynamic control properties from transmission to absorption

Modern stealth platforms require radomes capable of adaptively balancing electromagnetic transmission for radar operation and absorption for low observability. While the fixed electromagnetic responses of conventional radomes fail to address evolving detection threats. This study presents an electrically tunable radome with co-cured composite architecture, achieving dual-state electromagnetic performance through integrated diode-controlled resonance modulation. The proposed radome combines quartz fiber-reinforced polymer skins, low-loss polymethacrylimide (PMI) foam cores, and metallized functional layers embedded with PIN diodes. By leveraging equivalent circuit modeling and unit-cell design, the radome enables dynamic control from transmission to absorption. Experimental results demonstrate high transmission (3–4.5 GHz, >0.8 transmittivity) in the transmission state and strong absorptivity (2.5–5 GHz, >0.8 absorptivity) in the stealth state, with dynamic and continuous control governed by adjusting biasing voltage (0–53 V). Far-field measurements confirm minimal impact on the antenna radiation patterns (<1 dB radiation loss at 3.5–4 GHz). This validates an excellent compatibility with the enclosed antenna. Our work establishes a feasible scheme for multi-functional tunable radomes, which unifies dynamic electromagnetic control, rapid switching, and composite engineering, with applicability to next-generation stealth platforms requiring real-time radar-observability reconfiguration.