There is provided an antenna device for a vehicle capable of suppressing interference in a case where a plurality of antennas which receive signals in different frequency bands are close to one another. The antenna device for the vehicle includes a patch antenna and a capacitance loading element which are installed away from each other on an antenna base section which is attachable to a vehicle. The capacitance loading element is a part of an antenna capable of receiving a different use frequency band from which of the patch antenna, to form a three-dimensional shape in which a pair of linear conductors which respectively repeatedly turn in a predetermined direction are connected to each other via a linear connection conductor extending in a width direction of the antenna base section, and in the capacitance loading element, a length of a folded portion of each of the linear conductors is a non-resonant length of the patch antenna.

A detection system for a vehicle, including at least one detection device operable for detecting objects in a detection area. The detection device also includes a first emission antenna, a first reception antenna, and a plurality of extension portions. One of the plurality of extension portions is integrally formed as part of the first emission antenna, and another of the plurality of extension portions is integrally formed as part of the first reception antenna. The first emission antenna generates an emission wave at a predetermined angle which contacts objects in the first detection area and deflects of the objects in the first detection area, and returns to the first reception antenna as a return wave. In an embodiment, the first emission antenna includes at least one Vivaldi wing, and the first reception antenna includes at least one Vivaldi wing.

An antenna is installed on an installation surface of a wheel. The antenna includes a first conductor, a second conductor, one or more third conductors, a fourth conductor, and a feeding line. The first conductor and the second conductor face each other in a first axis. The one or more third conductors are located between the first conductor and the second conductor and extend in the first axis. The fourth conductor is connected to the first conductor and the second conductor and extends in the first axis. The feeding line is electromagnetically connected to the third conductor. The first conductor and the second conductor are capacitively connected via the third conductor. A surface of the fourth conductor faces the installation surface of the wheel in a second axis perpendicular to the first axis.

An antenna is installed on an installation surface of a wheel. The antenna includes a first conductor, a second conductor, one or more third conductors, a fourth conductor, and a feeding line. The first conductor and the second conductor face each other in a first axis. The one or more third conductors are located between the first conductor and the second conductor and extend in the first axis. The fourth conductor is connected to the first conductor and the second conductor and extends in the first axis. The feeding line is electromagnetically connected to the third conductor. The first conductor and the second conductor are capacitively connected via the third conductor. A surface of the fourth conductor faces the installation surface of the wheel in a second axis perpendicular to the first axis.

A sensor module includes: a metal member having a recessed portion; a resin portion embedded within the recessed portion; a radiator provided within the resin portion and configured to emit radio waves; a wireless communication portion provided within the resin portion and connected to the radiator; and a sensor connected to the wireless communication portion, wherein the metal member is insulated from the radiator by the resin portion and functions as a parasitic element.

A sensor module includes: a metal member having a recessed portion; a resin portion embedded within the recessed portion; a radiator provided within the resin portion and configured to emit radio waves; a wireless communication portion provided within the resin portion and connected to the radiator; and a sensor connected to the wireless communication portion, wherein the metal member is insulated from the radiator by the resin portion and functions as a parasitic element.

An antenna is described. This antenna includes: a ground plane; and antenna elements that are positioned in a first horizontal plane offset along a vertical direction from the ground plane. Moreover, the antenna elements are configured to generate a beam having a horizontal polarization. Furthermore, the antenna includes a planar reflector that is positioned in a second horizontal plane offset along the vertical direction from the first ground plane, so that the antenna elements are positioned between the ground plane and the planar reflector. During operation, a first reflection from the ground plane, the beam from the antenna elements, a second reflection from the planar reflector and diffractions from edges of the ground plane and the planar reflector combine to generate an antenna radiation pattern having a main beam approximately in a horizontal direction, e.g., at 10-15° from the horizontal direction.

An antenna is described. This antenna includes: a ground plane; and antenna elements that are positioned in a first horizontal plane offset along a vertical direction from the ground plane. Moreover, the antenna elements are configured to generate a beam having a horizontal polarization. Furthermore, the antenna includes a planar reflector that is positioned in a second horizontal plane offset along the vertical direction from the first ground plane, so that the antenna elements are positioned between the ground plane and the planar reflector. During operation, a first reflection from the ground plane, the beam from the antenna elements, a second reflection from the planar reflector and diffractions from edges of the ground plane and the planar reflector combine to generate an antenna radiation pattern having a main beam approximately in a horizontal direction, e.g., at 10-15° from the horizontal direction.

An antenna device includes a first antenna having a length corresponding to a first frequency, and arranged along a ground, a second antenna formed by a slot penetrating metal constituting the first antenna, and having a slot length corresponding to a second frequency higher than the first frequency, a first feeder wire for the first frequency, connected from the ground to the first antenna, a metal element for electromagnetic field coupling, arranged in a non-contact state relative to the second antenna, between the slot and the ground; and a second feeder wire for the second frequency, connected from the ground to the metal element.

A multi-core dielectric circular waveguide (MCDCW) is described. A hybrid mode excitation for multi-core dielectric filled circular waveguide fed parabolic antenna is also described. A multi-core dielectric circular waveguide with four cylinders of different relative permittivity (∈.sub.r) inside each other is used to generate the hybrid mode (HE.sub.11) directly without need for coupling TE.sub.11 and TM.sub.11 modes as in prior art corrugated waveguide feeders. This mode is preferable to be used as operating mode to feed the reflector. Four concentric cylinders of different relative permittivity ∈.sub.r are used as an example.