ANTENNA DEVICE

An antenna device includes a dielectric substrate having a first surface on which an antenna part is formed and a second surface on which a base plate is formed. The antenna part has one or more antenna patterns configured to act as radiating elements. The antenna patterns resonate in one or more resonance directions to incident waves having an operating frequency of the antenna part, thereby generating emitted waves having polarized waves different from those of transmitted/received waves which are transmitted/received by the antenna part. For each of the resonance directions, the antenna patterns include at least one line pattern having a width which is narrower than the total width of the antenna patterns in a direction perpendicular to the resonance direction.