Patent · US Expired

Call-waiting tone detection technique

US6496572B1 · kind B1 · utility

18Cited by
4References
55Claims
0Family size

Assignee

Inventors

Key dates

Filing dateDec 20, 2001
Grant dateDec 17, 2002
Priority date—
Expiry dateDec 20, 2021

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04M3/4281
  • WIPO fieldTelecommunications
  • WIPO sectorElectrical engineering

Abstract

Reliable detection of a call-waiting tone is provided by employing a correlation based technique. A modem or other device employing such a technique need not rely on carrier drop detection and is generally insensitive to other energy or noise on the line.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.