Millimeter-Wave High-Gain Magneto-Electric Dipole Antenna Array With Pillbox Corporate Feed Network

This article presents a high-gain antenna array with the use of magnetoelectric (ME) dipole antenna elements operating at millimeter-wave frequencies. The proposed array achieves wide bandwidth, high gain, and low sidelobe level (SLL) in its planar structure. A highly efficient power divider consisting of pillbox transition and corporate feed network is introduced to produce equal phase but nonuniform power distributions to all array elements such that it can be for suppressing the SLL of the array. The radiating element is constituted by a cavity-backed slot-coupled ME dipole, which offers a wide impedance bandwidth and a stable radiation pattern. A prototype of the antenna array is fabricated and measured to verify the proposed design. The array achieves an impedance bandwidth of 20.8% (for the reflection coefficient ≤ -10 dB), covering the frequency range from 54.2 to 66.8 GHz. The average gain of the array is 28.5 dBi in its operating bandwidth, with a peak gain of 29.6 dBi at 65 GHz. The lowest E-plane SLL level over the entire bandwidth is -18 dB. This proposed antenna array has potential applications in long-distance millimeter-wave communications due to its merits of wideband, high gain, and low SLL features.