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. 27, 1999
Filed:
Apr. 25, 1996
Sanjai Kohli, Manhattan Beach, CA (US);
Steven Chen, Cerritos, CA (US);
SiRF Technology, Inc., Santa Clara, CA (US);
Abstract
A spread spectrum receiver, such as a GPS car navigation system, uses multiple, parallel correlations of data in a wide capture window, permits seamless tracking and rapid reacquisition of satellite signals at speeds sufficient to permit position information updates during momentary views available of satellites in intersections. The received data is processed in 11 bit samples, for a total of 186 time segments per 1 msec code period, which are each Doppler shifted and multiplexed into 12 channels. The code correlations are performed 22 times per channel by shifting the 11 bit locally generated code by one bit each correlation. The chip rate of the incoming data is 2f.sub.0 and the correlations are performed at 48f.sub.0 providing a time magnification advantage of 24.