07423580 is referenced by 73 patents and cites 8 patents.

The present invention is an RF system and methods for finding a target T in three dimensional space configured to have a transponder disposed on the target T, a monitoring unit configured as a transceiver for determining or monitoring the location of the target T and an RF wireless communication system configured with a processor to repeatedly determine position, communication and other values between the transponder and monitoring unit and so as to generate a measured distance between units in three dimensional space by determining the measured distance of the target T by a spherical virtual triangulation relationship when successive values of said position information has a predetermined logical relationship relative to said previous values between said monitoring unit and transponder and/or slave unit disposed on the target T.

Title
Method and system of three-dimensional positional finding
Application Number
11/375161
Publication Number
7423580 (B2)
Application Date
March 14, 2006
Publication Date
September 9, 2008
Inventor
Evgenii Mikhienko
Novosibirsk
RU
Evgenii Vityaev
Novosibirsk
RU
Russ Markhovsky
Edgewater
MD, US
Agent
Bardmesser Law Group
Assignee
Invisitrack
MD, US
IPC
G01S 13/42
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