Wideband Conformal Folded Transmitarray Antenna With Low RCS

In this letter, a conformal folded transmitarray antenna (CFTA) is proposed and experimentally verified for the first time. It combines the properties of wide operational bandwidth and low radar cross section (RCS). The mechanism of cylindrical CFTA is analyzed based on ray tracing principle. For demonstration, a multifunctional transmitarray element integrating control of polarization, radiation, and scattering is designed. Polarization control acts as a polarization grid, enhancing wave reflection for antenna profile reduction. Radiation control improves antenna directionality by manipulating transmission phase. Scattering control disperses incident wave energy to reduce RCS. On these basis, a CFTA prototype is developed, and experimental results reveal that it obtains a peak gain of 22.3 dBi at 12.8 GHz, a 3-dB gain bandwidth of 31.4% (10.2–14 GHz) and a 5-dB RCS reduction bandwidth of 58% (11–20 GHz). Notably, by folding the wave path, the antenna profile is reduced to 1/2.4 (120 mm to 50 mm). The proposed CFTA demonstrates significant advantages in low-profile, wideband and low-RCS compared to conventional conformal TAs, highlighting its promising application potential for modern unmanned aerial vehicle.