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:
May. 19, 1998
Filed:
May. 10, 1995
Applicant:
Inventors:
William E Powell, Raleigh, NC (US);
David T Hayes, Raleigh, NC (US);
Assignee:
Alcatel Network Systems, Inc., Richardson, TX (US);
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
H03D / ;
U.S. Cl.
CPC ...
375373 ; 375375 ; 375376 ; 327156 ; 331 17 ; 331 27 ; 331D / ;
Abstract
A method and an apparatus are provided to achieve fast phase settling when a reference signal for a phase locked loop changes from a first frequency to a second frequency, such as during holdover recovery in a synchronous optical network. The present method acquires the second frequency with a phase locked loop (24). After the frequency is acquired, the integral register (39) of the phase locked loop (24) is loaded with the contents of the output frequency register (34) of the phase locked loop (24). The phase detector (28) of the phase locked loop (24) is then realigned to the reference signal.