Radio-communication vehicle identification system

• US 6,034,625 A
• Filed: 10/16/1998
• Issued: 03/07/2000
• Est. Priority Date: 10/17/1997
• Status: Expired due to Fees

• Current Assignee: NEC Corporation
• Original Assignee: NEC Corporation
• Inventors: Mitsuno, Atsushi
• Primary Examiner(s): POPE, DARYL C
• Application Number:
  US09/173,689
• Time in Patent Office: 508 Days
• Field of Search: 340/933, 340/539, 340/928, 340/937, 340/825.31, 340/825.34, 340/825.3, 340/825.69, 455/54.1, 455/54.2, 455/33.1, 342/44, 342/50
• US Class Current: 340/937
• CPC Class Codes: G08G 1/017 identifying vehicles G08G1/015, G08G1/054 take precedence
• CPC Class Codes: G08G 1/04 using optical or ultrasonic detectors

Abstract

A radio-communication vehicle identification apparatus includes first and second radio communication units, a directional finding unit, a vehicle classification unit, and a vehicle identification unit. The first radio communication unit is mounted on a vehicle. The second radio communication unit is placed at a gate through which the vehicle passes to perform radio communication with the first radio communication unit. The directional finding unit measures an arrival angle of a radio signal transmitted from the first radio communication unit with respect to a reference direction. The vehicle classification unit detects a length of the vehicle on the basis of image data obtained by photographing the vehicle and classifies the vehicle on the basis of a detection result. When the vehicle has reached a predetermined position on the gate, the vehicle identification unit determines whether the arrival angle output from the directional finding unit falls within an arrival angle range of the radio signal from the first radio communication unit, which corresponds to vehicle classification data output from the vehicle classification unit, and identifies the vehicle having the first radio communication unit on the basis of a determination result.

Claims

1. A radio-communication vehicle identification apparatus comprising:

first radio communication means mounted on a vehicle;

second radio communication means placed at a gate through which the vehicle passes to perform radio communication with said first radio communication means;

directional finding means for measuring an arrival angle of a radio signal transmitted from said first radio communication means with respect to a reference direction;

vehicle classification means for detecting a length of the vehicle on the basis of image data obtained by photographing the vehicle and classifying the vehicle on the basis of a detection result; and

vehicle identification means for, when the vehicle has reached a predetermined position on the gate, determining whether the arrival angle output from said directional finding means falls within an arrival angle range of the radio signal from said first radio communication means, which corresponds to vehicle classification data output from said vehicle classification means, and identifying the vehicle having said first radio communication means on the basis of a determination result.

2. An apparatus according to claim 1, wherein

said vehicle classification means comprises

image sensing means for photographing the vehicle and outputting the image data, and

vehicle length determination means for detecting the length of the vehicle on the basis of the image data from said image sensing means, classifying the vehicle on the basis of the detected vehicle length, and outputting the vehicle classification data.

3. An apparatus according to claim 1, wherein

when a plurality of vehicles are present in a communication area where radio communication can be performed, said second radio communication means time-divisionally assigns a radio signal transmission time to said first radio communication means of each of the plurality of vehicles, and

said directional finding means time-divisionally measures the arrival angle of the radio signal transmitted from said first radio communication means.

4. An apparatus according to claim 1, wherein

the arrival angle range of the radio wave is set between the arrival angle of a radio wave transmitted from said first radio communication means of a vehicle belonging to a first classification and reaching the predetermined position and the arrival angle of a radio wave transmitted from said first radio communication means of a vehicle following the vehicle belonging to the first classification and reaching the predetermined position.

7. An apparatus according to claim 2, wherein said vehicle length determination means classifies the vehicle on the basis of whether or not the length of the vehicle is larger than a reference value.

5. A radio-communication vehicle identification apparatus comprising:

first radio communication means mounted on a vehicle;

second radio communication means placed at a gate through which the vehicle passes to perform radio communication with said first radio communication means;

directional finding means for measuring an arrival angle of a radio signal transmitted from said first radio communication means with respect to a reference direction;

vehicle classification means for detecting a length of the vehicle on the basis of image data obtained by photographing the vehicle and classifying the vehicle on the basis of a detection result; and

vehicle identification means for, when the vehicle has reached a predetermined position on the gate, determining whether the arrival angle output from said directional finding means falls within an arrival angle range of the radio signal from said first radio communication means, which corresponds to vehicle classification data output from said vehicle classification means, and identifying the vehicle having said first radio communication means on the basis of a determination result;

wherein said vehicle identification means comprises;

first determination means for, when the vehicle has reached the predetermined position on the gate, determining whether the arrival angle is output from said directional finding means;

second determination means for obtaining one of a plurality of arrival angle ranges of the radio signal from said first radio communication means, which are set in advance, in accordance with the vehicle classification data from said vehicle classification means, and determining whether the arrival angle output from said directional finding means falls within the obtained arrival angle range; and

third determination means for determining, on the basis of determination results from said first and second determination means, whether the vehicle reaching the predetermined position is the vehicle having the first radio communication means.

6. A radio-communication vehicle identification apparatus comprising:

first radio communication means mounted on a vehicle;

second radio communication means placed at a gate through which the vehicle passes to perform radio communication with said first radio communication means;

directional finding means for measuring an arrival angle of a radio signal transmitted from said first radio communication means with respect to a reference direction;

vehicle classification means for detecting a length of the vehicle on the basis of image data obtained by photographing the vehicle and classifying the vehicle on the basis of a detection result;

vehicle identification means for, when the vehicle has reached a predetermined position on the gate, determining whether the arrival angle output from said directional finding means falls within an arrival angle range of the radio signal from said first radio communication means, which corresponds to vehicle classification data output from said vehicle classification means, and identifying the vehicle having said first radio communication means on the basis of a determination result; and

detection means for detecting that the vehicle has reached the predetermined position on the gate, and

wherein the predetermined position is set at a position where said directional finding means can detect the arrival angle of the radio signal from said first radio communication means.

8. A radio-communication vehicle identification apparatus comprising:

a first radio communication device mounted on a vehicle;

a second radio communication device placed at a location through which the vehicle passes, for performing radio communication with said first radio communication device;

a directional finder for measuring an arrival angle of a radio signal transmitted from said first radio communication device with respect to a reference direction;

a vehicle classification device for classifying on the basis of image data obtained by photographing the vehicle;

a vehicle length detector for detecting the length of the vehicle on the basis of the image data, classifying the vehicle on the basis of the detected vehicle length, and outputting the vehicle classification data; and

a vehicle identifier for when the vehicle has reached a predetermined position, determining whether the arrival angle output from said directional finder falls within an arrival angle range of the radio signal from said first radio communication device, which corresponds to vehicle classification data output from said vehicle classification device, and identifying the vehicle having said first radio communication device on the basis of a determination result.

9. An apparatus according to claim 8, wherein said vehicle identifier comprises:

a first determiner for, when the vehicle has reached the predetermined position, determining whether the arrival angle is output from said directional finder.

10. An apparatus according to claim 9, wherein said vehicle identifier comprises:

a second determiner for obtaining one of a plurality of arrival angle ranges of the radio signal from said first radio communication device, which are set in advance, in accordance with the vehicle classification data from said vehicle classifier, and determining whether the arrival angle output from said directional finder falls within the obtained arrival angle range.

11. An apparatus according to claim 10, wherein said vehicle identifier comprises:

a third determiner for determining, on the basis of determination results from said first and second determiner, whether the vehicle reaching the predetermined position is the vehicle having the first radio communication device.

12. An apparatus according to claim 8, further comprising:

a detector for detecting that the vehicle has reached the predetermined position.

13. An apparatus according to claim 12, wherein the predetermined position is set at a position where said directional finder can detect the arrival angle of the radio signal from said first radio communication device.

14. An apparatus according to claim 8, wherein said vehicle length detector classifies the vehicle on the basis of whether or not the length of the vehicle is larger than a reference value.

15. An apparatus according to claim 8, wherein where a plurality of vehicles are present in a communication area where radio communication can be performed, said second radio communication device time-divisionally assigns a radio signal transmission time to said first radio communication device of each of the plurality of vehicles.

16. An apparatus according to claim 15, wherein said directional finder time-divisionally measures the arrival angle of the radio signal transmitted from said first radio communication device.

17. An apparatus according to claim 8, wherein the arrival angle range of the radio wave is set between the arrival angle of a radio wave transmitted from said first radio communication device of a vehicle belonging to a first classification and reaching the predetermined position and the arrival angle of a radio wave transmitted from said first radio communication device of a vehicle following the vehicle belonging to the first classification and reaching the predetermined position.

18. An apparatus according to claim 9, wherein the arrival angle range of the radio wave is set between the arrival angle of a radio wave transmitted from said first radio communication device of a vehicle belonging to a first classification and reaching the predetermined position and the arrival angle of a radio wave transmitted from said first radio communication device of a vehicle following the vehicle belonging to the first classification and reaching the predetermined position.

19. An apparatus according to claim 10, wherein the arrival angle range of the radio wave is set between the arrival angle of a radio wave transmitted from said first radio communication device of a vehicle belonging to a first classification and reaching the predetermined position and the arrival angle of a radio wave transmitted from said first radio communication device of a vehicle following the vehicle belonging to the first classification and reaching the predetermined position.