US Patent 11489250 Electronic device

An antenna device includes one or more zeroth-order resonant antennas and a metal body. Each of the zeroth-order resonant antennas includes a ground plate configured to provide a ground potential, an opposing conductor arranged at a predetermined distance from the ground plate in a plate thickness direction of the ground plate, a power supply line electrically connected to the opposing conductor, and a short-circuit portion electrically connecting the opposing conductor and the ground plate. The metal body is configured to limit a propagation direction of a radio wave transmitted from or received by the one or more zeroth-order resonant antennas and has an opening.