Data processing: vehicles – navigation – and relative location – Navigation – Employing position determining equipment
Reexamination Certificate
1998-12-01
2001-07-31
Nguyen, Tan (Department: 3661)
Data processing: vehicles, navigation, and relative location
Navigation
Employing position determining equipment
C701S117000, C701S220000, C340S928000, C342S076000
Reexamination Certificate
active
06269302
ABSTRACT:
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a mobile object position detecting system such as a vehicle position detecting system or a vehicle identification system
2. Description of the Related Art
Recently, various systems have been developed as intelligence transport system (ITSs). One of such systems is an electronic toll collection (ETC) system.
In the tollgates of an ETC system, determination of whether a vehicle is an ETC vehicle or a non-ETC vehicle is important. For realizing this, an ETC system is suggested (see: A. Mitsuno et al., “Direction Finding Technology and Application to Radio-communication Vehicle Identification System”, NEC Technical Report, Vol, 50, No. 7, pp. 147-155, 1997). That is, a vehicle detector is provided for optically detecting whether or not a vehicle is present in a communication zone. In this case, the vehicle has an ETC transceiver. Also, a camera is provided to take a photograph of a vehicle. The transceiver is mounted on a dashboard of the vehicle.
Also, first and second antennas are installed in a row perpendicular to a lane on a pole. A signal is transmitted from the transceiver via the first antenna to a modulator/demodulator or vice versa. That is, the signal received at the first antenna from the transceiver is amplified, demodulated, and transmitted to a personal computer. On the other hand, a signal from the personal computer are modulated and transmitted from the first antenna to the transceiver.
A signal is supplied from the transceiver via the second antenna to a direction of angle (DOA) detector for calculating an angle of the vehicle. Each of the angles detected by the DOA detector is transmitted to the personal computer.
Further, a signal from the vehicle detectors is supplied to the personal computer, and the personal computer transmits a control signal to the camera.
The prior art ETC system will be explained later in detail.
In the prior art ETC system, however, the DOA detector is constructed on the basis of the principle of an interferometer (see FIG.
2
of the above-mentioned document). As a result, the DOA detector is large in size and high in cost. This also makes the ETC system large in size and high in cost.
SUMMARY OF THE INVENTION
It is an object of the present invention to provide a mobile object position detecting system such as a vehicle position detecting system capable of being small in size and low in cost.
According to the present invention, in a mobile object position detecting system for detecting a position of a mobile object having a transmitter, an elongated antenna system is provided for receiving a radio wave signal from the transmitter and outputting first and second electrical signals from first and second ends of the antenna system, respectively. A position detector calculates the position of the mobile object in accordance with a difference in time between the first and second electrical signals.
Also, according to the present invention, in a mobile object position detecting system for detecting a position of a mobile object having a transmitter, first and second antennas are located apart from each other, for receiving a radio wave signal from the transmitter and outputting first and second electrical signals, respectively. A position detector calculates the position of the mobile object in accordance with a difference in time between the first and second electrical signals.
REFERENCES:
patent: 3774209 (1973-11-01), Fleming et al.
patent: 5164732 (1992-11-01), Brockelsby
patent: 5570098 (1996-10-01), Searle et al.
patent: 5872525 (1999-02-01), Fukasawa et al.
patent: 5973638 (1999-10-01), Robbins et al.
patent: 50-62659 (1975-05-01), None
patent: 53-40910 (1978-04-01), None
patent: 61-216537 (1986-09-01), None
patent: 2-92507 (1990-07-01), None
patent: 4-190183 (1992-07-01), None
patent: 4-215016 (1992-08-01), None
patent: 6-230113 (1994-08-01), None
patent: 9-16886 (1997-01-01), None
patent: 9-287908 (1997-11-01), None
English translation of Jananese Patent No. 06-230113.*
English translation of Japanese Patent No. 09-287908.*
A. Mitsuno et al., “Direction Finding Technology and Application to Radio-Communication Vehicle Identification System”, NEC Technical Report, vol. 50, No. 7, pp. 147-155, 1997 (month is not available).
T. Nakahara et al., “Characteristics of Zigzag Slot Leakage Coaxial Cable”, Fifty Anniversary Proc. of the Institute of Electronics and Communication Engineers, 1967 (month is not available).
NEC Corporation
Nguyen Tan
Sughrue Mion Zinn Macpeak & Seas, PLLC
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