Folded Transmitarray Antennas Based on 1-Bit Metasurface With Broadband and Wide-Angle Beam-Scanning Capacity

An electronically reconfigurable folded transmitarray antenna (RFTA) with wideband and wide-angle beam-scanning capacity is proposed. The RFTA is composed of a reconfigurable metasurface (RMS), a polarization conversion metasurface (PCMS), and a linearly polarized feed antenna. Each unit cell of the RMS is symmetrically integrated with two PIN diodes. By controlling the on–off state of the diodes, the RMS can perform two functions: 1-bit phase encoding and linear polarization conversion across a broad bandwidth (BW). The PCMS is a novel wideband polarization converter with stable polarization conversion performance for wide incident angle. The wideband performance of the RMS and PCMS endows the RFTA with wide-angle beam-scanning capacity over a broad frequency range. The experimental results demonstrate beam scanning over angles from −50° to +50° in the frequency range of 8.1–11.3 GHz, with a peak gain of 15.93 dBi, a maximum aperture efficiency of 9.2%, and a 3-dB gain bandwidth of 33%.