Wide-Angle Scanning Heterogeneous Antenna Array Using Asymmetrically-Fed Magneto-Electric Dipole

In this paper, a ±90˚ beam-scanning heterogeneous antenna array (HAA) consisting of asymmetrically-fed magneto-electric (AF-ME) dipole elements is proposed for the first time. In the design of AF-ME dipole antenna, two offsets are introduced to excite the operating mode of planar pseudo-Yagi antenna in traditional ME dipole antenna. Different from the beam tilting elements in the existing HAAs, this proposed AF-ME dipole element exhibits stable antenna gains and half-power beam-widths (HPBWs) at different main beam directions, great cross-polarization isolations, and self-decoupling characteristics. As seen from the measured results, even when the scanning angle achieves ±90˚, this designed HAA exhibits a scan loss of less than 2.8 dB, a sidelobe level (SLL) of less than -10 dB, a cross-polarization isolation of greater than 31 dB, and a port isolation of greater than 18 dB without any decoupling structures within 23.9-24.4 GHz (2.1%). Therefore, this proposed heterogeneous antenna array is promising for the detection without blind spots in 24-GHz short-range automotive radar systems.