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:
Feb. 18, 1997
Filed:
Sep. 12, 1995
Applicant:
Inventors:
Yoshinori Rokugo, Tokyo, JP;
Masaaki Itoh, Tokyo, JP;
Assignee:
NEC Corporation, Tokyo, JP;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
H03D / ;
U.S. Cl.
CPC ...
375376 ; 327147 ; 327156 ; 331 10 ; 331 18 ;
Abstract
Each of primary and secondary random-walk filters has longer and shorter time constants. A multi-valued phase comparator generates a start signal if a phase error generated when an abrupt frequency change occurs exceeds a given value. In response to the start signal, the primary and secondary random-walk filters are set to the shorter time constants. A timer is started by the start signal, and upon elapse of a predetermined period of time, sets the primary and secondary random-walk filters to the longer time constants.