06415223 is referenced by 137 patents.

An interruption-free hand-held positioning method and system, carried by a person, includes an inertial measurement unit, a north finder, a velocity producer, a positioning assistant, a navigation processor, a wireless communication device, and a display device and map database. Output signals of the inertial measurement unit, the velocity producer, the positioning assistant, and the north finder are processed to obtain highly accurate position measurements of the person. The user's position information can be exchanged with other users through the wireless communication device, and the location and surrounding information can be displayed on the display device by accessing a map database with the person position information.

Title
Interruption-free hand-held positioning method and system thereof
Application Number
9/726996
Publication Number
6415223 (B1)
Application Date
November 29, 2000
Publication Date
July 2, 2002
Inventor
Hiram McCall
Simi Valley
CA, US
Ching Fang Lin
Simi Valley
CA, US
Agent
David and Raymond Patent Group
US
Agent
Raymond Y Chan
US
Assignee
American GNC Corporation
CA, US
IPC
G01C 21/00
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