Effective Magnetic-Loop Array Antenna With Enhanced Gain in the Azimuth Plane

Based on a modified annular ring coupled circular patch antenna, a two-magnetic current-loop array antenna is designed, fabricated, and characterized. The prototype antenna has omnidirectional radiation pattern in the azimuth plane, and the beam peak features an elevation angle of 18
^°
with a maximum gain of 4.2 dB. In the azimuth plane, a gain of 3.36 dB is achieved, which is about 1.6 dB higher than the value for a single-loop antenna in the small radius extreme. The compact and low-profile structure makes the antenna easy to be conformal to other surfaces.