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:
Nov. 26, 2013
Filed:
Mar. 11, 2009
Mangesh Chansarkar, Irvine, CA (US);
Gang Xie, Orange, CA (US);
Gengsheng Zhang, Cupertino, CA (US);
Mangesh Chansarkar, Irvine, CA (US);
Gang Xie, Orange, CA (US);
Gengsheng Zhang, Cupertino, CA (US);
CSR Technology Holdings Inc., San Jose, CA (US);
Abstract
The present invention provides methods of performing GNSS receivers' satellite signal acquisition and TTFF while taking advantage of SBAS signals. Due to a SBAS satellite's geostationary position and typically strong signal, the SBAS satellite signal can be acquired more quickly than a GPS satellite signal. Once a SBAS satellite signal is acquired the Doppler frequency search uncertainty may be reduced for remaining GNSS satellites which are to be acquired. Furthermore, a satellite search list may be optimized to search for satellites close to the line of sight (LOS) of the SBAS satellite for which a signal has been acquired, in receiver 'warm' and 'hot' start modes. Moreover, since a SBAS signal sub-frame is only one second long, which is shorter than six seconds for a GPS signal sub-frame, synchronization of the SBAS signal sub-frame may be achieved faster than for GPS signals. With aided time information, a receiver may compute the absolute time of week (TOW) from a sub-frame synchronized SBAS signal. Therefore, TTFF can be achieved without necessarily waiting for TOW to be decoded from a GPS signal.