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:
Jan. 23, 2001
Filed:
Jul. 30, 1999
Applicant:
Inventors:
Robert K. Froelich, Sunnyvale, CA (US);
Forrest Fulton, Los Altos Hills, CA (US);
Assignee:
CellNet Data Systems, Inc., San Carlos, CA (US);
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
H04K 1/00 ;
U.S. Cl.
CPC ...
H04K 1/00 ;
Abstract
The actual carrier frequency of a spread spectrum signal is found by tuning a pair of correlators to a pair of search frequencies and then correlating the spread spectrum signal against one or more reference signals to produce a pair of correlation magnitude values. The ratio of the difference between the correlation magnitude values to the sum of the correlation magnitude values determines the offset between the actual carrier frequency and an estimated carrier frequency.