A navigation system for use in a vehicle including a route-calculating section and a route guide control section. The route-calculating section searches for an optimum route according to conditions set for the search. The guide control section provides displays necessary to guide the driver of the vehicle, and guides the driver by speech. This guide control has a landmark name-setting section which sets the names of landmarks according to information about the landmarks, the information retrieved from a guidance information storage section according to information about the present position from a present position-determining section. A display section displays a whole route map indicating the selected route according to instructions from the route guidance control section. At the same time, the names of the landmarks are presented on the display section. When the navigation system guides the driver to a destination via a tollway such as a toll highway, the name of an entry/exit interchange connecting to the highway is displayed. This permits the driver to take a familiar route up to this interchange.
For qualification for traffic preemption an area is defined and if the vehicle is in the area it can obtain preemption. The vehicle's position is determined, in one embodiment, by use of differential GPS.
An in-car navigation apparatus produces a concept of a voice message such as a guide of an advancing route or a guide of an arrival to be informed at a point on a set drive route where voice information is to be given by means of the control section thereof, and produces a message sentence from a table defining a sentence pattern corresponding to the concept of a voice message and an device storing voice waveform information by means of a detachable voice information memorizing section. Thereby, the changes of the sentence patterns of voice messages and so forth can easily be done without varying the program of the apparatus.
The text to speech conversion system distinguishes geographical names based upon the present position and includes a text input unit for inputting text data, a position coordinator input unit for inputting present location information of the text to speech conversion system, and a text normalizer connected to the text input unit and the position coordinator input unit for capable of generating a plurality of pronunciation signals indicative of a plurality of pronunciations for a common portion of the text data, the text normalizer selecting one of the pronunciation signals based upon the present location information.
A method and system for determining the location of a mobile position determining system with respect to a destination. In one embodiment, a mobile position determining system has a communication device coupled thereto. Position information of the mobile position determining system is transmitted, via the communication device, to a destination position information database. The destination position information database contains position information of at least one destination. A position comparator then generates range and bearing information indicative of the relative position of the mobile position determining system with respect to the at least one destination. An output device then reports the relative position of the mobile position determining system with respect to the at least one destination to a user of the mobile position determining system.
A navigation system calculates a route from a present position of a vehicle to a destination and provides guidance based on the calculated route. When the vehicle is within a given distance from a next approaching branch point requiring guidance, branch points existing within a given distance from next approaching branch point are determined and direction information for the branch points is acquired. The acquired direction information is compared with direction information at the next approaching branch point, and a common direction information is displayed based on the result of the comparison. Also, the navigation system according to the present invention detects a name of an interchange where the vehicle is to exit from the course and a distance to said interchange based on the present position of the vehicle in case the road where the vehicle is currently driven along is an expressway or a toll road. The navigation system according to the present invention calculates a route from the present position to the destination and properly calculates and provides guidance for the expected time of arrival at the destination as the vehicle moves.
