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:
Mar. 27, 2012
Filed:
Jan. 05, 2006
Cdma frequency acquisition using a simplified crystal oscillator that is not temperature compensated
James A. Hutchison, Iv, San Diego, CA (US);
Ling Hang, San Diego, CA (US);
Robbin D. Hughes, San Diego, CA (US);
James A. Hutchison, IV, San Diego, CA (US);
Ling Hang, San Diego, CA (US);
Robbin D. Hughes, San Diego, CA (US);
QUALCOMM Incorporated, San Diego, CA (US);
Abstract
CDMA code channels are acquired using a crystal oscillator that is not temperature compensated and that generates a tuning signal with relatively large frequency error (e.g., +/−5 ppm). Channel acquisition is first attempted at no offset from a start frequency that is obtained by fitting an ideal temperature/frequency error curve to available actual data points. Following unsuccessful pilot acquisition, the offset frequency is stepped in a 'spiral' manner, and pilot acquisition is retried. When the pilot and synchronization channels are successfully acquired, but the system identification is unexpected, an adjacent channel image has been acquired, and the offset frequency is bumped by a large step (e.g., 15 kHz). Pilot acquisition is retried using spiral stepping. The crystal oscillator is calibrated after each successful acquisition of the pilot, synchronization and paging channels by retaining a data point in a frequency adjustment table for the temperature at which frequency acquisition was successful.