A Wideband Via-Free Magneto-Electric Dipole Antenna Array with High Aperture Efficiency

A novel design is proposed to achieve a high-aperture-efficiency wideband magneto-electric (ME) dipole antenna array. By employing an air gap and parasitic patches in a conventional via-free ME dipole, surface waves are effectively suppressed while maintaining a broad bandwidth. The proposed antenna element achieves a 48% impedance bandwidth with SWR < 2, exhibiting a stable unidirectional radiation pattern. Finally, a 256-element antenna array, fed by an equal power divider constructed by stripline, achieves a peak gain of 30.5 dBi and over 85% aperture efficiency (AE) across the 22.5-32.5 GHz operating bandwidth.