US Patent No: 6,061,018

Number of patents in Portfolio can not be more than 2000

Method and system for using altitude information in a satellite positioning system

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Abstract

A method and apparatus for determining a position of a mobile satellite positioning system (SPS) receiver. In one example of a method, a cell object information is determined; this cell object information comprises at least one of a cell object location or a cell object identification. An altitude is determined from the cell object information which is selected based upon a cell site transmitter which is in wireless communication with a cell based communication system which is coupled to (and typically integrated with) the mobile SPS receiver. The position of the mobile SPS receiver is calculated using the altitude which is determined from the cell object information. In another example of a method, an altitude pseudomeasurement is determined from an estimate of an altitude of the mobile SPS receiver. This estimate of the altitude may be from a cell based information source in a cell based system or may be an average altitude of the area of radio coverage of a wireless basestation in the non-cell based system. The altitude pseudomeasurement may be used as a redundant measurement with fault detection and isolation techniques to determine whether at least one pseudorange has a faulty condition. Alternatively (or in addition), a comparison of the estimated altitude to a calculated altitude determines a condition of at least one pseudorange between an SPS satellite and the mobile SPS receiver. In one embodiment of this example, the position is determined from a position solution algorithm, and if the condition is a first state (not a fault state) the at least one pseudorange is used in the position solution algorithm.

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First Claim

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Patent Owner(s)

Patent OwnerAddressTotal Patents
SNAPTRACK, INC.SAN JOSE, CA58

International Classification(s)

Inventor(s)

Inventor Name Address # of filed Patents Total Citations
Sheynblat, Leonid Hillsborough, CA 119 2784

Cited Art

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Patent Citation Ranking

Forward Cites

Patent Info (Count) # Cites Year
 
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TELECOMMUNICATION SYSTEMS, INC. (31)
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QUALCOMM INCORPORATED (13)
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Fast Location. Net, LLC, a Texas corporation (11)
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CSR PLC (4)
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TRIMBLE NAVIGATION LIMITED (2)
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ASULAB S.A. (1)
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EADS DEUTSCHLAND GMBH (1)
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EDIZONE, LC (1)
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SPORTVISION, INC. (1)
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TELEFONAKTIEBOLAGET LM ERICSSON (PUBL) (1)
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XONE, INC. (1)
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YMAX COMMUNICATIONS CORP. (1)
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Other [Check patent profile for assignment information] (3)
8,467,320 Voice over internet protocol (VoIP) multi-user conferencing 0 2006
7,616,064 Digital synthesizer for low power location receivers 0 2008
8,369,967 Alarm system controller and a method for controlling an alarm system 0 2011