Patent attributes
An antenna apparatus includes a patch antenna unit in which a radiation conductor and a ground conductor plate are arranged so as to face each other with an insulating material disposed therebetween, a power-feed point is provided at a position slightly offset from the center of the radiation conductor, and a high-frequency electric field is supplied between the radiation conductor and the ground conductor plate; a surface-wave propagation suppression area in which a surface-wave propagation suppression mechanism for suppressing surface-wave propagation is mounted in an outer surrounding area in the offset direction of the power-feed point in which an electric-field intensity is generally maximum within the end portion of the radiation conductor plate; and an insulating area in which an electric-field intensity between the radiation conductor plate and the ground conductor plate is relatively low and the surface-wave propagation suppression mechanism is not arranged.
