06414635 is referenced by 507 patents.

A geographic based communications service system that includes a network and a plurality of access points connected to the network and arranged at known locations in a geographic region. One or more service providers or information providers may be connected to the network to provide services or information on the network. Content provided by the service providers may be based on the known geographic location of the user of a portable computing device (PCD). The known geographic location may be determined with a high degree of precision, using one or more access points and one of several different techniques. In one embodiment, the geographic location of the PCD may be determined within a radius of ten feet. Access points may be configured to determine the bearing of a signal received from a PCD, as well as the strength of the signal transmitted by the PCD. Access points may also be configured to send and receive signals with time stamps. These time stamps may be used to calculate signal travel time, thereby allowing a determination of the distance between an access point and a PCD. Each access point may include location circuitry. The location circuitry may include both analog and digital circuitry configured to perform the various methods used to determine the precise geographic location.

Title
Geographic-based communication service system with more precise determination of a user's known geographic location
Application Number
9/694747
Publication Number
6414635 (B1)
Application Date
October 23, 2000
Publication Date
July 2, 2002
Inventor
James W Thompson
Austin
TX, US
Brett B Stewart
Austin
TX, US
Agent
Conley Rose & Tayon PC
US
Agent
Jeffrey C Hood
US
Assignee
Wayport
TX, US
IPC
G01S 3/02
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