A Low-Sidelobe Circularly Polarized Continuous Beam-Scanning Array Using Double-Layer Rotated Structure for Ku-Band Satellite Communications

In this letter, a low-sidelobe level (SLL) circularly polarized (CP) beam-scanning array antenna based on a double-layer rotated structure is proposed for
Ku
-band satellite communications. It is comprised of a 16 × 24 CP substrate integrated waveguide slot antenna array and a rotatable feeding network. Detailed design methodology and working mechanism of the proposed antenna array are presented and analyzed, in particular, the method of achieving low SLL in Blass matrix design. A prototype was fabricated and measured, and the measured results indicate that an AR < 1.5 dB and a max SLL suppression of 19.4 dB at 11.95 GHz can be achieved. Its superiorities of low profile, low SLL, high gain, and continuous beam-scanning ability make the proposed array antenna a promising candidate for satellite communications.