Patent · US Expired

Branching unit for telecommunications optical cable systems

US5655036A · kind A · utility

11Cited by
2References
5Claims
0Family size

Assignee

Inventor

Key dates

Filing dateJun 1, 1994
Grant dateAug 5, 1997
Priority date
Expiry dateJun 1, 2014

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04B10/07
  • WIPO fieldTelecommunications
  • WIPO sectorElectrical engineering

Abstract

An active branching unit for interconnecting three cables (two trunk cables and one spur cable) each including optical fibres. In a first interconnection configuration fibres of the trunk cables are connected together via the spur cable. Optical switch means, comprised for example by an erbium doped fibre amplifier (EDFA) (20) and an optical attenuator (21) in series, are disposed between optical fibres of the two trunk cables and are such as to pass telecommunications traffic between the trunk cables when, for example, there is fault in the spur cable and an alternative configuration is required. In this case a pump signal is applied to the EDFA (20) and the loss of the attenuator (21) overcome so that traffic can pass directly between the trunk cables and thus be diverted from the spur cable. This path switching can be achieved automatically.

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