Patent · US Expired

Cordless telephone system

US4882746A · kind A · utility

41Cited by
6References
22Claims
0Family size

Inventor

Key dates

Filing dateMar 17, 1988
Grant dateNov 21, 1989
Priority date
Expiry dateMar 17, 2008

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04M1/65
  • WIPO fieldTelecommunications
  • WIPO sectorElectrical engineering

Abstract

A cordless telephone system has a master unit connected to a telephone line and having a radio transceiver and a plurality of sub-units having radio transceivers and transmittable to and receivable from the telephone line through the master unit. Speech from the telephone line can be transferred between any sub-units, and speech by press-to-talk system is enabled between any sub-units through the master unit. A multi-purpose controller is provided in the master unit to enable control of an equipment by dialing from a sub-unit. For example, a tape recorder is operated, an automatic response/record function is operated, an interphone function is operated, a call from the telephone line can be directed to any sub-unit by a signal from the sub-unit, and all sub-units can be simultaneously or sequentially called from the telephone line. In the speech between sub-units by the press-to-talk system, signals representing start and end of the speech are generated by the sub-unit to control holding and release of an external telephone line of a master unit repeater so that speech with the external line is restored immediately after the end of the speech between the sub-units. When one sub-uni…

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