04819174 is referenced by 89 patents and cites 7 patents.

A road navigation system comprises a plurality of guidance information transmitter systems disposed along a route, each transmitter system generating current location information in the form of extremely-low-powered electric waves, and a guidance signal generator system for providing guidance information for the benefit of a user. The guidance signal generator system comprises a receiver unit for receiving the current location information from the guidance information transmitter system, an input unit for inputting destination information, a memory unit for storing available map information and the inputted destination information which can be prepared as route information to be traced, a data processor unit for comparing the route information with the current location information received by the receiver unit and for producing the guidance information, and an output unit for communicating the guidance information to the user. The guidance signal generator system can provide the user with accurate guidance information within a relatively small area covered by the low-powered electric waves from the transmitter system.

Title
Road navigation system
Application Number
7/8573
Publication Number
4819174
Application Date
January 29, 1987
Publication Date
April 4, 1989
Inventor
Takayuki Nonami
Hyogo
JP
Yoshio Tooko
Hyogo
JP
Kenichi Furuno
Hyogo
JP
Agent
Wolf Greenfield & Sacks
Assignee
Mitsubishi Denki Kabushiki Kaisha
JP
IPC
G06F 15/50
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