A Waveguide Cavity Antenna for Automotive 4D Millimeter-Wave Radar Applications

A waveguide cavity antenna is proposed for automotive 4D millimeter-wave radar applications. The radiation structure of the antenna, consisting of stacked open waveguide cavities, is fed by a three-way waveguide power divider. The antenna achieves a radiation pattern with low sidelobes and a narrow beamwidth by adjusting the amplitudes and phases of the power divider's output ports. The half-power beamwidth (HPBW) in the azimuth plane is less than 60 degrees. On the other hand, the HPBW in the elevation plane is less than 16 degrees, while the sidelobe levels are suppressed below -20 dB. Over a wide operating bandwidth of 76-81 GHz, the antenna gain exceeds 16 dBi, while the reflection is suppressed below -15 dB.