Abstract: Electrical performance of a vehicular antenna device constant is kept constant. A vehicular antenna device 1 includes: a first antenna 31; a second antenna 32; a first cable 35 for the first antenna 31; a second cable 36 for the second antenna 32; and a housing 10 that holds the first antenna 31 and the second antenna 32. The first cable 35 and the second cable 36 are held in a predetermined region of one surface of the housing 10.

Abstract: A vehicular antenna device including a cover, and a plurality of monopole antennas accommodated in an accommodation space formed by the cover, in which the plurality of monopole antennas is arranged in a direction intersecting a desired direction.

Abstract: An antenna device includes: a first planar antenna for a linearly polarized wave, the first planar antenna including a first feeding portion; and a second planar antenna for a linearly polarized wave, the second planar antenna including a second feeding portion that overlaps the first feeding portion in a plan view when viewed in a direction perpendicular to a predetermined surface of the first planar antenna, wherein the linearly polarized wave of the first planar antenna and the linearly polarized wave of the second planar antenna intersect each other.

Abstract: A vehicular antenna device includes: a base; a case forming an accommodation space, with the base; and a first antenna accommodated in the accommodation space, the first antenna supporting radio waves in a desired frequency band, wherein at least a portion of the first antenna is arranged at a proximate position close to the case.

Abstract: An antenna device (100) for a vehicle includes an antenna case (101), an antenna base (102) forming an accommodation space together with the antenna case (101), a first antenna element (108) that is accommodated in the accommodation space and that at least transmits or receives a circularly polarized wave; a second antenna element (110) that is arranged close to the first antenna element (108) and that at least transmits or receives a linearly polarized wave; and at least one parasitic element (111), (112a), (112b), or (112c) serving as a reflector or a waveguide for the second antenna element (110).