GPS/self-contained combination type navigation system

Patent 4903212 Issued on February 20, 1990. Estimated Expiration Date:

March 11, 2008. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.

Abstract Claims Description Full Text

Patent References

Navigational error correcting system
Patent #: 3940597
Issued on: 02/24/1976
Inventor: DiMatteo

Loran compensated magnetic compass
Patent #: 4024382
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Inventor: Fowler

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Patent #: 4335433
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Inventor: Bauer , et al.

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Patent #: 4459667
Issued on: 07/10/1984
Inventor: Takeuchi

Apparatus for calculating position of vehicle
Patent #: 4713767
Issued on: 12/15/1987
Inventor: Sato , et al.

Positioning system for a vehicle Patent #: 4731613
Issued on: 03/15/1988
Inventor: Endo , et al.

Inventors

Assignee

Japan Radio Co., Ltd.

Application

No. 167093 filed on 03/11/1988

US Classes:

701/216, Having an self-contained position computing means (e.g., dead reckoning)342/357.14, Combined with secondary navigation system (i.e., LORAN, gyroscope, inertial, dead reckoning, etc.)342/451, By computer342/461, With speed determination701/200, NAVIGATION701/208, For use in a map data base system701/300, RELATIVE LOCATION702/94Position measurement

Examiners

Primary: Lall, Parshotam S.
Assistant: Trans, V. N.

Attorney, Agent or Firm

Lowe, Price, Leblanc, Becker & Shur

Foreign Patent References

0111143 JP 05/13/1986
0138113 JP 06/13/1986
0138114 JP 06/13/1986
0167813 JP 07/13/1986

International Classes

G06F 015/50
G01C 021/00

Foreign Application Priority Data

1987-03-13 JP

Abstract

In a global positioning system (GPS)/self-contained combination type navigation system for a vehicle, the GPS navigation data are received by the GPS antenna of the navigation system which are simultaneously transmitted from more than 3 pieces of satellites inclusively. From the GPS navigation data, GPS type velocity data is calculated, whereas self-contained type velocity data is calculated from self-contained type navigation data such as azimuth data and drive-distance data of the vehicle. Only when a difference between the self-contained type velocity data and the GPS type velocity data exceeds a threshold velocity, the GPS type velocity data is voided so as to determine the present position of the vehicle.