US Patent 11495884 Antenna device and communication device

An antenna device includes a dielectric substrate, an emitting electrode, a power feed circuit that feeds power to the emitting electrode, and a filter circuit formed on a path connecting the emitting electrode to the power feed circuit, the filter circuit is constituted by two or more circuits that are cascade connected, each of the two or more circuits is either a HPF or a LPF, and the antenna device does not have a resonant frequency of the emitting electrode and has two or more resonant frequencies different from the resonant frequency of the emitting electrode, each of which is formed by the emitting electrode and a corresponding one of the two or more circuits.