Wide-angle low-scattering transmitarray antenna based on transmit-reflect selective metasurface

Abstract A high-gain transmitarray (TA) antenna with low radar cross section (RCS) properties is presented in this paper. Compared with conventional high-profile multilayer designs, we introduce a transmit-reflect selective metasurface (TRSMS) integrated with high-gain transmission and random scattering functions, achieving a reduced thickness of 0.13 λ0 (where λ0 is the wavelength at the center frequency). For the meta-atom design, we combine geometric rotation and dimension optimization to realize 1-bit independent transmit and reflection phase modulation, respectively. Moreover, in metasurface coding strategy, we employ an initial phase optimization method and a simulated annealing algorithm (SAA) to determine the optimal coding matrices. The experimental results demonstrate high- performance radiation characterized by the peak gain of 23.6 dB, maximum aperture efficiency (AE) of 28.5%, and 3 dB gain bandwidth of 18.4%. For x-polarization, measured 10 dB RCS reduction bandwidth under transverse magnetic (TM) 0°-45° and transverse electric (TE) 0°-20° incidence are 9.02-11.36 GHz. For y-polarization, 10 dB RCS reduction bandwidth under TM 0-60° and TE 0-30° incidence is 8.82-10.96 GHz.