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:
Jun. 06, 2000
Filed:
Dec. 22, 1997
Applicant:
Inventors:
Christopher Henry Becker, Calgary, CA;
Joseph Chi Chan, Calgary, CA;
Assignee:
Nortel Networks Corporation, Montreal, CA;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
H04M / ;
U.S. Cl.
CPC ...
379386 ; 379372 ; 379350 ;
Abstract
A method and apparatus for detecting a stutter dial tone SDT signal. The method includes the steps of, receiving a received signal from a subscriber loop, generating a signal envelope of the received signal, generating a threshold parameter value from the signal envelope, counting the number of threshold parameter crossings undertaken by the signal envelope and producing a signal indicating SDT signal has been received when number of threshold crossings exceeds a predefined value.