An antenna apparatus includes a ground plane, a plurality of first patch antenna patterns arranged on a level higher than the ground plane and each configured to transmit and/or receive a first radio frequency signal of a first frequency, a plurality of second patch antenna patterns arranged on a level higher than the ground plane and each having a size smaller than a size of each of the first patch antenna patterns, wherein the plurality of second patch antenna patterns include at least one feed patch antenna pattern configured to transmit and/or receive a second radio frequency signal of a second frequency different from the first frequency, and at least one dummy patch antenna pattern which is not fed any of the first and second radio frequency signals.