06594576 is referenced by 298 patents.

A system and a method for determining and disseminating current traffic information is presented. A traffic data compilation computer linked to a data network collects location data from mobile units, each of which is associated with an identification number. The computer compiles the location data, calculates the velocity of each mobile unit, compares the velocity of each mobile unit against speed limit data stored in a memory, and stores the difference. The traffic data compilation computer determines the traffic condition based on the difference between the velocity of each mobile unit and the speed limit. In addition, traffic data compilation computer may determine the fastest route between point A and point B under the current traffic conditions. Traffic data compilation computer determines the possible routes between point A and point B, retrieves the velocity data from a database, and derives the estimated travel time for each of the possible routes.

Title
Using location data to determine traffic information
Application Number
9/898682
Publication Number
6594576 (B2)
Application Date
July 3, 2001
Publication Date
July 15, 2003
Inventor
James D Fay
Palo Alto
CA, US
Xinnong Yang
San Rafael
CA, US
Rodric C Fan
Fremont
CA, US
Agent
MacPherson Kwok Chen & Heid
US
Agent
Edward C Kwok
US
Assignee
At Road
CA, US
IPC
G06F 17/00
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