Abstract: An antenna device includes: an antenna configured to radiate a radio wave; a substrate at which the antenna is provided; and a cover which covers the substrate from a radiation surface side of the antenna, the cover is a dielectric material, a maximum distance between the cover and the substrate in a normal direction to the substrate is smaller than ½ of a free space wavelength of the radio wave, and a thickness of the cover is smaller than ½ of an effective wavelength of the radio wave in the cover.

Abstract: An antenna device includes: an antenna unit provided as a conductive pattern on a substrate; and a propagation preventive unit which is provided adjacent to the antenna unit and prevents propagation of radiation waves of the antenna unit along the substrate, and the propagation preventive unit is provided as a conductive pattern on the substrate, has plural patches arranged in a prescribed pattern, and has, at an end on a side of the antenna unit, a stepped structure in which a distance from a position of the antenna unit to one of the patches closest to the position of the antenna unit varies by a prescribed interval every time the position in an extension direction of a feed line of the antenna unit is changed by a prescribed distance.

Abstract: An antenna device includes: an antenna configured to radiate a radio wave; a substrate at which the antenna is provided; and a cover which covers the substrate from a radiation surface side of the antenna, the cover is a dielectric material, a maximum distance between the cover and the substrate in a normal direction to the substrate is smaller than ½ of a free space wavelength of the radio wave, and a thickness of the cover is smaller than ½ of an effective wavelength of the radio wave in the cover.

Abstract: There is provided a microstrip antenna. A plurality of dielectric layers are stacked. An antenna is provided on the uppermost dielectric layer of the plurality of dielectric layers. Conductor layers are respectively provided on lower surfaces of the dielectric layers. The conductor layers have different dimensions in a plane direction thereof so that electromagnetic waves to be radiated from the conductor layers are cancelled with each other.

Abstract: An antenna device includes: an antenna unit provided as a conductive pattern on a substrate; and a propagation preventive unit which is provided adjacent to the antenna unit and prevents propagation of radiation waves of the antenna unit along the substrate, and the propagation preventive unit is provided as a conductive pattern on the substrate, has plural patches arranged in a prescribed pattern, and has, at an end on a side of the antenna unit, a stepped structure in which a distance from a position of the antenna unit to one of the patches closest to the position of the antenna unit varies by a prescribed interval every time the position in an extension direction of a feed line of the antenna unit is changed by a prescribed distance.

Abstract: An antenna apparatus includes: an antenna array that: i) includes a plurality of antennas arranged next to each other in a predetermined direction, ii) is supplied with power from a power source, and iii) transmits radio waves; and a plurality of dummy antennas that: i) are provided on opposite sides of the antenna array in the predetermined direction, ii) are supplied with power from an electric field leaked from the antennas of the antenna array, and iii) transmit radio waves. Thus, it is possible to prevent an accuracy of detecting a target from deteriorating.

Abstract: There is provided a microstrip antenna. A plurality of dielectric layers are stacked. An antenna is provided on the uppermost dielectric layer of the plurality of dielectric layers. Conductor layers are respectively provided on lower surfaces of the dielectric layers. The conductor layers have different dimensions in a plane direction thereof so that electromagnetic waves to be radiated from the conductor layers are cancelled with each other.

Abstract: An antenna apparatus includes: an antenna array that: i) includes a plurality of antennas arranged next to each other in a predetermined direction, ii) is supplied with power from a power source, and iii) transmits radio waves; and a plurality of dummy antennas that: i) are provided on opposite sides of the antenna array in the predetermined direction, ii) are supplied with power from an electric field leaked from the antennas of the antenna array, and iii) transmit radio waves. Thus, it is possible to prevent an accuracy of detecting a target from deteriorating.