Vehicle antenna device with side wall lens
Provided is an antenna device with a simple configuration and in which it is possible to control the directivity in various directions. An antenna device according to the present invention is provided with: an array antenna that includes at least one antenna element disposed on a first surface of a substrate and that forms beams in respective directions having a plurality of angles including a first angle relative to the first surface of the substrate; and a side wall that is provided on at least a partial periphery of the at least one antenna element and that refracts, in a direction along the substrate, a first beam in the direction having the first angle.
1. An antenna apparatus mounted on a first vehicle, comprising:
an array antenna that includes at least one antenna element disposed on a first surface of a substrate and that forms beams in respective directions, the directions respectively forming a plurality of angles including a first angle with respect to the first surface of the substrate and the first surface of the substrate being provided along a traveling surface of the first vehicle; and
a side wall that is provided in at least a part of a periphery of the at least one antenna element and that refracts a first beam in a direction along the substrate, the first beam being in a direction forming the first angle, wherein
the array antenna forms the first beam for communicating with a first radio communication apparatus mounted on a second vehicle positioned in the direction along the substrate, and
the array antenna forms a second beam in a direction forming a second angle different from the first angle for communicating with a second radio communication apparatus positioned in different direction than the direction of the first radio communication apparatus along the substrate, a position of the second radio communication apparatus being higher than a position of the antenna apparatus.
2. The antenna apparatus according to claim 1 , wherein:
the array antenna includes a phase shifter that controls an excitation phase of the at least one antenna element, and
a control circuit that controls a phase of the phase shifter.
3. The antenna apparatus according to claim 1 , wherein:
the array antenna includes a reflector on a surface opposite to the first surface of the substrate.
4. The antenna apparatus according to claim 3 , wherein:
an insulation layer is provided between the at least one antenna element and the reflector.
5. The antenna apparatus according to claim 1 , wherein:
the side wall includes a first side surface on which the first beam is made incident, and a second side surface from which the first beam is emitted after being refracted thereon, and
an angle of inclination of the first side surface with respect to the first surface of the substrate and an angle of inclination of the second side surface with respect to the first surface of the substrate are set based on the first angle.
6. The antenna apparatus according to claim 5 , wherein:
the angle of inclination of the first side surface with respect to the first surface of the substrate is 65° or less.
7. The antenna apparatus according to claim 5 , wherein:
the first side surface has a tapered shape such that the first side surface is away from an axis vertical to the first surface of the substrate as a distance of the first side surface from the substrate increases.
8. The antenna apparatus according to claim 5 , wherein:
the second side surface is vertical to the first surface of the substrate.
9. The antenna apparatus according to claim 5 , wherein:
the second side surface has a lens shape.
10. The antenna apparatus according to claim 1 , wherein:
the at least one antenna element is a plurality of antenna elements,
the plurality of antenna elements are disposed on the substrate in a one-dimensional arrangement direction, and
the side wall is provided on an extension line of the arrangement direction.
11. The antenna apparatus according to claim 1 , wherein:
the at least one antenna element is a plurality of antenna elements,
the plurality of antenna elements are disposed on the substrate in a two-dimensional direction, and
the side wall is provided at a position surrounding the plurality of antenna elements.
12. The antenna apparatus according to claim 1 , wherein:
the at least one antenna element has an operating frequency included in at least one band selected from a quasi-millimeter-wave band, a millimeter-wave band, and a terahertz band.
13. The antenna apparatus according to claim 1 , wherein:
the side wall is filled with a dielectric.
14. The antenna apparatus according to claim 1 , wherein:
the side wall has at least a height that allows a beam in a direction forming an angle of 30° with respect to the first surface of the substrate to be made incident.
15. The antenna apparatus according to claim 1 , wherein:
a third vehicle is positioned in the direction along the substrate,
one of the second vehicle and the third vehicle is positioned in front of the first vehicle,
the other one of the second vehicle and the third vehicle is positioned rearward of the first vehicle, and
the array antenna forms a third beam in a direction forming a third angle different from the first angle and the second angle for communicating with a third radio communication apparatus mounted on the third vehicle.