US Patent 10355335 Vehicle antenna device

A vehicle antenna device includes: an antenna base; an antenna case which is overlaid on the antenna base; and an antenna element and an amplifier board which are disposed inside the antenna case. The antenna base has: a resin-made base which has an opening; and a metal-made base which is smaller in area than the resin-made base, the metal-made base being disposed on the resin-made base so as to close the opening, and having a cylindrical portion for attachment to a vehicle body. A conductor plate is attached to a surface of the resin-made base, the surface being opposite to a placement surface of the metal-made base.