Patent · US Expired

Telephone ring signal detector

US6556673B1 · kind B1 · utility

5Cited by
2References
20Claims
0Family size

Assignee

Inventor

Key dates

Filing dateNov 12, 1999
Grant dateApr 29, 2003
Priority date
Expiry dateNov 12, 2019

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04M1/82
  • WIPO fieldTelecommunications
  • WIPO sectorElectrical engineering

Abstract

A telephone ring signal detector is coupled to a telecommunication line for detecting a first telephone ring signal, and for discriminating the first telephone ring signal from other line signals on the line. This detector comprises an event generator, coupled to the line, for receiving an incoming signal and for generating an initial event signal and an ending event signal, and a signal characteristic generator, coupled to the line and to the event generator, for generating a signal characteristic of the incoming signal after the initial event signal. This detector further comprises a signal characteristic limit device, for generating a predetermined signal characteristic range limit of the first telephone ring signal, and a signal characteristic comparator coupled to the signal characteristic generator, to the signal characteristic limit device and to the event generator, for comparing the signal characteristic with the predetermined signal characteristic range limit. A valid compare signal is generated when the signal characteristic is within the predetermined signal characteristic range limit. A ring detect signal is generated during the first quarter cycle time period of the f…

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