Compact Wideband Wide-Angle Scanning Millimeter-Wave Planar Antenna Array With WAIM

This paper proposes a compact millimeter-wave (mmWave) planar antenna array with wideband and wide-angle scanning capabilities. The proposed design incorporates a segmented patch to extend the bandwidth and utilizes metal vias to suppress non-radiative mode. A substrate-integrated back cavity (SIBC) structure is introduced to suppress surface waves, improving wide-angle impedance matching (WAIM) in the E-plane. Additionally, a square-ring meta-surface (SRMS) enhances WAIM in the H-plane. A fabricated 6×6 array demonstrates a bandwidth of 23.16–29.28 GHz (23.3%) and scanning ranges of ±70° in the Eplane and ±60° in the H-plane, providing a viable pathway for compact mmWave systems requiring concurrent wideband and wide-angle scanning.