Patent · US Expired

Ultrahigh-speed clock extraction circuit

US7024122B2 · kind B2 · utility

3Cited by
3References
13Claims
0Family size

Assignee

Inventors

Key dates

Filing dateNov 1, 2002
Grant dateApr 4, 2006
Priority date
Expiry dateSep 22, 2024

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04L61/50
  • WIPO fieldDigital communication
  • WIPO sectorElectrical engineering

Abstract

In an ultrahigh-speed clock extraction circuit wherein a local pulse generating light source 22 for generating a local optical pulse stream synchronized in bit phase with an input optical signal pulse stream is placed in a phase-locked loop, when repetition frequencies of the input optical signal pulse stream and the local optical pulse stream bear a particular relationship, a frequency demultiplier 32 and multipliers 43 and 52 are set so that the frequency of a modulation signal for an optical modulator 41 and a frequency which is a natural-number multiple of the modulation signal frequency, and the frequency of a down-converted version of an optical pulse stream output from a photodetector 42 differ from each other.

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