A Low-Scattering Reconfigurable Metasurface-Based Reflectarray With High Polarization Isolation

In this letter, an electrically-reconfigurable metasurface-based reflectarray (RA) is proposed with dynamic regulation of both radiation and scattering properties. Integrated with positive-intrinsic-negative (PIN) diodes and resistors, the designed polarization-dependent metasurface is featured with dynamic 1-bit phase control in the x-polarization channel and wideband wave absorption in the y-polarization channel, enabling wave manipulation with high polarization purity and isolation. Fed by a Vivaldi antenna, the RA achieves dynamic 2- dimensional (2D) beam-scanning and wideband dual-polarized low-scattering under two time-division-duplexing mechanisms. As experimental demonstration, a prototype comprising 576 independently controlled meta-atoms is fabricated and measured results conform well to simulated ones, accomplishing dynamic beam-steering up to ± 60°, a 3-dB gain bandwidth of 25%, a peak aperture efficiency of 19.1%, and a polarization isolation higher than 20 dB when switched to the radiation mode. Moreover, wideband monostatic and bistatic RCS reduction are observed in dual linear polarization channels at the low-scattering mode. The well-behaved RA may find applications in wireless communication, detection, and low-observable platforms.