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 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 two-dimensional (2-D) 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 radar cross section (RCS) reduction is 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.