The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Apr. 16, 2002
Filed:
Jul. 25, 2000
Matthew Rabinowitz, Palo Alto, CA (US);
Bradford W. Parkinson, Los Altos, CA (US);
Clark E. Cohen, Palo Alto, CA (US);
David G. Lawrence, Mountain View, CA (US);
The Board of Trustees of the Leland Stanford Junior University, Stanford, CA (US);
Abstract
Disclosed herein is a system for rapidly resolving position with centimeter-level accuracy for a mobile or stationary receiver [ This is achieved by estimating a set of parameters that are related to the integer cycle ambiguities which arise in tracking the carrier phase of satellite downlinks [ In the preferred embodiment, the technique involves a navigation receiver [ simultaneously tracking transmissions [ from Low Earth Orbit Satellites (LEOS) [ together with transmissions [ from GPS navigation satellites [ The rapid change in the line-of-sight vectors from the receiver [ to the LEO signal sources [ due to the orbital motion of the LEOS, enables the resolution with integrity of the integer cycle ambiguities of the GPS signals [ as well as parameters related to the integer cycle ambiguity on the LEOS signals [ These parameters, once identified, enable real-time centimeter-level positioning of the receiver [ In order to achieve high-precision position estimates without the use of specialized electronics such as atomic clocks, the technique accounts for instabilities in the crystal oscillators driving the satellite transmitters, as well as those in the reference [ and user [ receivers. In addition, the algorithm accommodates as well as to LEOS that receive signals from ground-based transmitters, then re-transmit frequency-converted signals to the ground.