Patent ID: 6975272

Claim:
A circularly polarized wave antenna device comprising: a dielectric substrate provided on a ground conductor; a plurality of electrodes provided on the dielectric substrate to face the ground conductor, the plurality of electrodes forming capacitors together with the ground conductor; a radiating conductor plate made of a metal plate and arranged above the dielectric substrate at a predetermined gap; and a plurality of leg pieces bent toward the dielectric substrate side at a plurality of locations on the radiating conductor plate, wherein two electrical lengths on the radiating conductor plate that are generated in directions passing a center of the radiating conductor plate and being orthogonal to each other are equal to each other, the leg pieces contain two leg pieces provided on each of first and second lines that pass the center of the radiating conduct plate, the two leg pieces are orthogonal to each other at locations except a central portion of the radiating conductor plate, the leg pieces are connected to the electrodes, respectively, and areas of the electrodes to which the two leg pieces provided on the first line are connected are different from those of the electrodes to which the two leg pieces provided on the second line are connected.