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. 19, 2013
Filed:
Feb. 21, 2006
Seong Taek Chung, Redwood City, CA (US);
Vinay Murthy, San Diego, CA (US);
Alok Kumar Gupta, Encinitas, CA (US);
Fuyun Ling, San Diego, CA (US);
Seong Taek Chung, Redwood City, CA (US);
Vinay Murthy, San Diego, CA (US);
Alok Kumar Gupta, Encinitas, CA (US);
Fuyun Ling, San Diego, CA (US);
Qualcomm Incorporated, San Diego, CA (US);
Abstract
Techniques for performing frequency control using dual-loop automatic frequency control (AFC) are described. The dual-loop AFC includes an inner loop that corrects short-term frequency variations (e.g., due to Doppler effect) and an outer loop that corrects long-term frequency variations (e.g., due to component tolerances and temperature variations). In one design, a first inner loop is implemented for frequency control of a first system (e.g., a broadcast system), a second inner loop is implemented for frequency control of a second system (e.g., a cellular system), and at least one outer loop is implemented for adjusting a reference frequency used to receive signals from the first and second systems. Each inner loop estimates and corrects the frequency error in an input signal for the associated system and may be enabled when receiving the input signal from the system. The reference frequency may be used for frequency downconversion, sampling and/or other purposes.