Patent · US Expired

Data communication apparatus for use in a telephone system

US3937889A · kind A · utility

131Cited by
12References
6Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJan 15, 1973
Grant dateFeb 10, 1976
Priority date—
Expiry dateJan 15, 1993

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04M11/062
  • WIPO fieldTelecommunications
  • WIPO sectorElectrical engineering

Abstract

A data transmission system utilizing the telephone voice communication network for transmitting data between the location of a telephone subscriber's handset and a central station. A data transmitter is capacitively coupled to a bridge tap on the subscriber loop at the subscriber's handset and a data receiver is capacitively coupled to a bridge tap on the subscriber loop at the associated telephone company central office. The data transmissions occur at frequencies outside the standard telephone voice transmission frequency band of the system thereby providing continuous data transmission service without interfering with the normal voice communication function of the system.

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