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:
Dec. 29, 2009
Filed:
Dec. 29, 2006
Chun Wang, San Mateo, CA (US);
Shaowei Han, Palo Alto, CA (US);
Chun Wang, San Mateo, CA (US);
Shaowei Han, Palo Alto, CA (US);
SiRF Technology Holdings, Inc., San Jose, CA (US);
Abstract
A Global Navigation Satellite System (GNSS) receiver and associated method capable of tracking weak GNSS signals from a plurality of GNSS satellites. In a preferred embodiment, code and carrier tracking loops are initially closed around the code phase, carrier frequency, and data bit edge estimates handed over from an acquisition mode. In subsequent tracking, early, prompt, and late copies of the code replica are correlated with the incoming signal. The prompt correlations are coherently integrated over an extended updating interval for data bit edge and sign estimation as well as for carrier phase and frequency error discrimination whereas the early and late correlations are used for code error discrimination. Code delay and carrier phase and frequency errors are used to update the code and carrier tracking loop filters. Together with data bits, they form observables of a GNSS signal's time and frequency parameters for timing and position fixing.