Antenna apparatus and communication method employing it

• US 20060139225A1
• Filed: 12/23/2005
• Published: 06/29/2006
• Est. Priority Date: 12/28/2004
• Status: Active Grant

• Current Assignee: Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corporation)
• Original Assignee: Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corporation)
• Inventors: Kusunoki, Hideki, Tanaka, Toshiyasu, Taguchi, Yutaka
• Granted Patent: US 7,336,234 B2
• Time in Patent Office: Days
• US Class Current: 343/770
• CPC Class Codes: B60C 23/0408 transmitting the signals by non-mechanical means from the wheel or tyre to a vehicle body mounted receiver
• CPC Class Codes: B60C 23/0444 Antenna structures, control or arrangements thereof, e.g. for directional antennas, diversity antenna, antenna multiplexing or antennas integrated in fenders
• CPC Class Codes: H01Q 1/2241 used in or for vehicle tyres
• CPC Class Codes: H01Q 9/36 with top loading
• CPC Class Codes: H01Q 9/40 Element having extended radiating surface

Abstract

An antenna apparatus includes a monopole antenna forming an antenna element having a metal shell body, and the antenna element has an approximately conical part, a vertex of which is on the side of a power supply part.

Claims

1. An antenna apparatus comprising a monopole antenna forming an antenna element having a metal shell body, wherein:

said antenna element has an approximately conical part, a vertex of which is on the side of a power supply part.

2. The antenna apparatus as claimed in claim 1, further comprising:

a capacitative member at a head part of the antenna element located on a side opposite to said power supply part side.

3. The antenna apparatus as claimed in claim 1, further comprising:

a reflecting plate covering and shielding the power supply part side of said antenna element.

5. The antenna apparatus as claimed in claim 1, transmitting radio waves to trigger a predetermined transmitting operation to a transmitter mounted in an underbody part of a vehicle.

7. The antenna apparatus as claimed in claim 5, wherein:

said transmitter is mounted in a wheel, and

said predetermined transmitting operation comprises an operation of transmitting an ID number of said transmitter.

9. The antenna apparatus as claimed in claim 1, disposed in a vehicle cabin for receiving radio waves from a transmitter mounted in a wheel.

11. The antenna apparatus as claimed in claim 9, wherein:

said transmitter comprises respective transmitters mounted in respective wheels; and

said antenna apparatus is disposed at a position of a vehicle body roof part approximately equidistant from the respective wheels in such a manner that a head part of the antenna element faces vertically downward.

13. A communication method, comprising the step of:

transmitting radio waves to a wheel side apparatus mounted in a wheel from the antenna apparatus claimed in claim 1 for changing an operation state of the wheel side apparatus, in a state in which a central axis of the conical shape part of said antenna apparatus may be approximately coaxial with a central axis of the wheel.

4. An antenna apparatus comprising a monopole antenna forming an antenna element having a metal shell body, wherein:

said antenna element has a rotationally symmetrical shape, and has a part having a radius different along an axis of said rotationally symmetrical shape.

6. The antenna apparatus as claimed in claim 4, transmitting radio waves to trigger a predetermined transmitting operation to a transmitter mounted in an underbody part of a vehicle.

8. The antenna apparatus as claimed in claim 6, wherein:

said transmitter is mounted on a wheel, and

said predetermined transmitting operation comprises an operation of transmitting an ID number of said transmitter.

10. The antenna apparatus as claimed in claim 4, disposed in a vehicle cabin for receiving radio waves from a transmitter mounted in a wheel.

12. The antenna apparatus as claimed in claim 10, wherein:

said transmitter comprises respective transmitters mounted in respective wheels; and

said antenna apparatus is disposed at a position of a vehicle body roof part approximately equidistant from the respective wheels in such a manner that a head part of the antenna element faces vertically downward.