04903212 is referenced by 250 patents and cites 10 patents.

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.

Title
GPS/self-contained combination type navigation system
Application Number
7/167093
Publication Number
4903212
Application Date
March 11, 1988
Publication Date
February 20, 1990
Inventor
Seiichiro Hirata
Hyogo
JP
Makoto Mikuriya
Hyogo
JP
Koji Yamada
Tokyo
JP
Harumasa Hojo
Tokyo
JP
Chogo Sekine
Tokyo
JP
Tatsumi Kageyama
Hyogo
JP
Kazuhiro Yokouchi
Hyogo
JP
Agent
Lowe Price Leblanc Becker & Shur
Assignee
Japan Radio
JP
Mitsubishi Denki Kabushiki Kaisha
JP
IPC
G01C 21/00
G06F 15/50
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