On-vehicle radar device and vehicle

• US 9,799,949 B2
• Filed: 07/14/2015
• Issued: 10/24/2017
• Est. Priority Date: 09/30/2014
• Status: Expired due to Fees

• Current Assignee: Nidec Corporation
• Original Assignee: Nidec Corporation
• Inventors: Kamo, Hiroyuki
• Primary Examiner(s): Vo, Tung
• Application Number:
  US14/798,597
• Publication Number:
  US 20160093944A1
• Time in Patent Office: 833 Days
• Field of Search: 348148
• CPC Class Codes: B32B 17/10036 comprising two outer glass sheets
• CPC Class Codes: G01S 13/02 Systems using reflection of radio waves, e.g. primary radar systems; Analogous systems
• CPC Class Codes: G01S 13/867 Combination of radar systems with cameras
• CPC Class Codes: G01S 13/931 of land vehicles
• CPC Class Codes: G01S 2013/93276 in the windshield area
• CPC Class Codes: G01S 7/024 using polarisation effects in waveguides H01P1/165; for aerials H01Q, e.g. H01Q15/22, H01Q15/24, H01Q19/195
• CPC Class Codes: G01S 7/027 Constructional details of housings, e.g. form, type, material or ruggedness
• CPC Class Codes: G01S 7/032 Constructional details for solid-state radar subsystems
• CPC Class Codes: H01Q 1/1271 for mounting on windscreens
• CPC Class Codes: H01Q 1/3233 particular used as part of a sensor or in a security system, e.g. for automotive radar, navigation systems
• CPC Class Codes: H01Q 1/3266 using the mirror of the vehicle
• CPC Class Codes: H01Q 1/422 comprising two or more layers of dielectric material H01Q1/425 takes precedence
• CPC Class Codes: H01Q 13/02 Waveguide horns

Abstract

An on-vehicle radar device includes a mount and an antenna configured to transmit a transmission wave from an inner side of laminated glass, which includes an innermost glass layer, an outermost glass layer, and an intermediate resin layer, and receive a reflected wave. The antenna includes a transmitting antenna. When the mount is mounted on a bracket, the incident angle of the transmission wave on the innermost glass layer is greater than a Brewster angle on the inner surface of the innermost glass layer, and the incident angle of the transmission wave on the outermost glass layer is less than or equal to a Brewster angle between the outermost glass layer and the intermediate resin layer.

Claims

1. An on-vehicle radar device comprising:

a mount configured to be mounted on a bracket that is fixed to one of an innermost glass layer of laminated glass, a rear-view mirror placed on an inner side of the innermost glass layer, and a ceiling, the laminated glass including the innermost glass layer, an outermost glass layer, and an intermediate resin layer that is sandwiched between the innermost glass layer and the outermost glass layer; and

an antenna configured to transmit a transmission wave from the inner side of the innermost glass layer to an outer side of the outermost glass layer and to receive a reflected wave that enters from the outer side of the outermost glass layer to the inner side of the innermost glass layer, the transmission wave being a radio wave in a millimeter wave band;

wherein

the antenna includes a transmitting antenna configured to transmit the transmission wave;

a vertical polarization component of the transmission wave relative to the laminated glass is greater than a horizontal polarization component thereof;

when the mount is mounted on the bracket, an incident angle of the transmission wave on the innermost glass layer at a center of a main lobe of the transmitting antenna is greater than a Brewster angle on an inner surface of the innermost glass layer, and an incident angle of the transmission wave on the outermost glass layer at the center of the main lobe is less than or equal to a Brewster angle between the outermost glass layer and the intermediate resin layer; and

a difference between the Brewster angle and the incident angle of the transmission wave on the innermost glass layer at the center of the main lobe of the transmitting antenna is less than or equal to about 25% of a difference between 90 degrees and the Brewster angle.

2. The on-vehicle radar device according to claim 1, wherein

the antenna includes another transmitting antenna configured to transmit another transmission wave that has a different radiation pattern from a radiation pattern of the transmission wave;

and

when the mount is mounted on the bracket, an incident angle of the another transmission wave on the innermost glass layer at a center of a main lobe of the another transmitting antenna is greater than the Brewster angle on the inner surface of the innermost glass layer, and an incident angle of the another transmission wave on the outermost glass layer at the center of the main lobe is less than or equal to the Brewster angle between the outermost glass layer and the intermediate resin layer.

3. The on-vehicle radar device according to claim 1, wherein the intermediate resin layer is made of polyvinyl butyral.

4. The on-vehicle radar device according to claim 2, wherein the intermediate resin layer is made of polyvinyl butyral.

5. The on-vehicle radar device according to claim 1, wherein the antenna includes at least one of a horn antenna, a lens antenna, a printed antenna, a microstrip antenna, and a slit antenna.

6. The on-vehicle radar device according to claim 1, wherein the antenna is a horn antenna.

7. The on-vehicle radar device according to claim 1, further comprising:

a camera configured to observe an outside from an inner side of the laminated glass; and

a cover that is configured to cover the antenna and the camera.

8. The on-vehicle radar device according to claim 2, further comprising:

a camera configured to observe an outside from an inner side of the laminated glass; and

a cover that is configured to cover the antenna and the camera.

9. The on-vehicle radar device according to claim 3, further comprising:

a camera configured to observe an outside from an inner side of the laminated glass; and

a cover that is configured to cover the antenna and the camera.

10. The on-vehicle radar device according to claim 4, further comprising:

a camera configured to observe an outside from an inner side of the laminated glass; and

a cover that is configured to cover the antenna and the camera.

11. A vehicle comprising:

a vehicle body;

a drive mechanism configured to move the vehicle body;

laminated glass that is fixed to the vehicle body and located between a vehicle interior and a vehicle exterior; and

an on-vehicle radar device that is fixed directly or indirectly to one of an inner surface of the laminated glass, a rear-view mirror that is placed on an inner side of the inner surface, and a ceiling;

wherein

the laminated glass includes an innermost glass layer, an outermost glass layer, and an intermediate resin layer that is sandwiched between the innermost glass layer and the outermost glass layer;

the on-vehicle radar device includes an antenna configured to transmit a transmission wave from an inner side of the innermost glass layer to an outer side of the outermost glass layer and receive a reflected wave that enters from the outer side of the outermost glass layer to the inner side of the innermost glass layer, the transmission wave being a radio wave in a millimeter wave band;

the antenna includes a transmitting antenna configured to transmit the transmission wave;

a vertical polarization component of the transmission wave relative to the laminated glass is greater than a horizontal polarization component thereof;

an incident angle of the transmission wave on the innermost glass layer at a center of a main lobe of the transmitting antenna is greater than a Brewster angle on an inner surface of the innermost glass layer, and an incident angle of the transmission wave on the outermost glass layer at the center of the main lobe is less than or equal to a Brewster angle between the outermost glass layer and the intermediate resin layer; and

a difference between the Brewster angle and the incident angle of the transmission wave on the innermost glass layer at the center of the main love of the transmitting antenna is less than or equal to about 25% of a difference between 90 degrees and the Brewster angle.

12. The vehicle according to claim 11, wherein

the antenna includes another transmitting antenna configured to transmit another transmission wave that has a different radiation pattern from a radiation pattern of the transmission wave;

an incident angle of the another transmission wave on the innermost glass layer at a center of a main lobe of the another transmitting antenna is greater than the Brewster angle on the inner surface of the innermost glass layer, and an incident angle of the another transmission wave on the outermost glass layer at the center of the main lobe is less than or equal to the Brewster angle between the outermost glass layer and the intermediate resin layer; and

the intermediate resin layer is made of polyvinyl butyral.