Patent · US Expired

Digital terminal address transmitting for CATV

US4684981A · kind A · utility

31Cited by
5References
4Claims
0Family size

Assignee

Inventors

Key dates

Filing dateNov 8, 1984
Grant dateAug 4, 1987
Priority date
Expiry dateNov 8, 2004

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04H20/79
  • WIPO fieldTelecommunications
  • WIPO sectorElectrical engineering

Abstract

Digital signals of up to four different modes are produced for transmission over an unused television channel in an existing cable television transmission line. No more bandwidth is required than that normally required by a single existing television channel. The various modes of digital signals all include synchronizing signals and service bit signals which are used to address any of the numerous terminals at the receiving side to control access to the various modes of digital signals transmitted over the single channel. By controlling the transmission of the modes to have constant time intervals, which can be selected based upon different sampling times, high quality audio signals may be transmitted or/and data channels or monaural audio signals, all of which may be transmitted over the single cable television transmission line.

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