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Passive Tracking System and MethodSystem and methods are disclosed for passively determining the location of a moveable transmitter utilizing a pair of phase shifts at a receiver for extracting a direction vector from a receiver to the transmitter. In a preferred embodiment, a phase difference between the transmitter and receiver is extracted utilizing a noncoherent demodulator in the receiver. The receiver includes antenna array with three antenna elements, which preferably are patch antenna elements placed apart by one-half wavelength. Three receiver channels are preferably utilized for simultaneously processing the received signal from each of the three antenna elements. Multipath transmission paths for each of the three receiver channels are indexed so that comparisons of the same multipath component are made for each of the three receiver channels. The phase difference for each received signal is determined by comparing only the magnitudes of received and stored modulation signals to determine a winning modulation symbol.
Document ID
20050237885
Acquisition Source
Headquarters
Document Type
Other - Patent
Authors
Arndt, G. Dickey
(NASA Johnson Space Center Houston, TX, United States)
Ngo, Phong H.
(NASA Johnson Space Center Houston, TX, United States)
Chen, Henry A.
(NASA Johnson Space Center Houston, TX, United States)
Phan, Chau T.
(NASA Johnson Space Center Houston, TX, United States)
Bourgeois, Brian A.
(NASA Johnson Space Center Houston, TX, United States)
Dusl, John
(NASA Johnson Space Center Houston, TX, United States)
Hill, Brent W.
(NASA Johnson Space Center Houston, TX, United States)
Date Acquired
August 23, 2013
Publication Date
June 7, 2005
Subject Category
Mechanical Engineering
Distribution Limits
Public
Copyright
Work of the US Gov. Public Use Permitted.
Patent
US-Patent-6,903,685
Patent Application
US-Patent-Appl-SN-994989|US-Patent-Appl-SN-612562
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