Navigation system for an automotive vehicle

Claim 1

A vehicle navigation system for identifying a desired map route between a first position of a vehicle and a second position, which comprises: (a) map means for storing a plurality of road maps and speed limit values for roads therein; (b) input means for enabling a user to select said first and second positions; (c) selecting means for selecting a road map from those stored in said map means on the basis of said selected first and second positions of said vehicle; (d) traffic receiving means for receiving traffic information including speed rates transmitted in a data representation format of variable length differences from said stored speed limit values for respective roads contained on said selected road map over a wireless channel from a centrally located database to said vehicle; and (e) means for determining a route of shortest duration between said first position and said second position from said selected road map on the basis of said speed rates received by said traffic receiving means and the length of travel between said first and second positions of said vehicle.

Claim 20

A method of determining a best navigation route for an automotive vehicle, comprising the steps of: determining an actual position of the automotive vehicle; selecting a desired destination of the vehicle; transmitting information indicative of said actual position of the vehicle and said desired destination from said vehicle to a central database; selecting, at said central database, a best navigation route for said vehicle based on said information transmitted by said vehicle and on speed rates of traffic in routes between said actual position and said desired destination of said vehicle, stored within said central database; transmitting said best navigation route as map information from said central database to said vehicle; periodically transmitting actual positions and speed rates of each of a plurality of said vehicles that also transmit said desired destination to said central database; averaging, at said central database, speed rate information received from said plurality of vehicles; transmitting updated traffic information to said vehicles, said updated information being based on said averaging of speed rate information.

Claim 21

A method of determining a best navigation route for an automotive vehicle, comprising the steps of: determining an actual position of the automotive vehicle; selecting a desired destination of the vehicle; transmitting information indicative of said actual position of the vehicle and said desired destination from said vehicle to a central database; selecting, at said central database, a best navigation route for said vehicle based on said information transmitted by said vehicle and on speed rates of traffic in routes between said actual position and said desired destination of said vehicle, stored within said central database; transmitting said best navigation route as map information from said central database to said vehicle; periodically transmitting actual positions and speed rates of each of a plurality of said vehicles that also transmit said desired destination to said central database; averaging, at said central database, speed rate information received from said plurality of vehicles; transmitting updated traffic information to said vehicles, said updated information being based on said averaging of speed rate information.

Claim 22

A method of determining a best navigation route from an actual position of an automotive vehicle to a selected desired destination which comprises the steps of: (a) determining the actual position of said automotive vehicle; (b) storing a plurality of road maps and speed limit values for roads on said maps; (c) selecting a desired destination from one of said stored road maps; (d) identifying the navigation routes from the actual position of said automotive vehicle to said selected desired destination; (e) receiving traffic information on the basis of the actual position of said automotive vehicle including speed rates of said identified navigation routes transmitted in a data representation format of variable length differences from said stored speed limit values for respective roads over a wireless channel from a centrally located database to said automotive vehicle; (f) determining travel time necessary to travel each of said identified navigation routes based on the traffic information received; and (g) selecting one of said identified navigation routes having the shortest travel time.

Claim 23

A method of determining a best navigation route from an actual position of an automotive vehicle to a selected desired destination which comprises the steps of: (a) determining the actual position of said automotive vehicle; (b) storing a plurality of road maps and speed limit values for roads on said maps; (c) selecting a desired destination from one of said stored road maps; (d) identifying the navigation routes from the actual position of said automotive vehicle to said selected desired destination; (e) receiving traffic information on the basis of the actual position of said automotive vehicle including speed rates of said identified navigation routes transmitted in a data representation format of variable length differences from said stored speed limit values for respective roads over a wireless channel from a centrally located database to said automotive vehicle; (f) determining travel time necessary to travel each of said identified navigation routes based on the traffic information received; and (g) selecting one of said identified navigation routes having the shortest travel time.