Patent · US Active

Skew compensation and tracking in communications systems

US8687974B2 · kind B2 · utility

27Cited by
4References
22Claims
0Family size

Assignee

Inventors

Key dates

Filing dateAug 8, 2011
Grant dateApr 1, 2014
Priority date
Expiry dateOct 19, 2031

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04L25/03057
  • WIPO fieldTelecommunications
  • WIPO sectorElectrical engineering

Abstract

Compensation for in-phase (I) and quadrature (Q) timing skew and offset in an optical signal may be achieved based on the correlation between derivatives of I and Q samples in the optical signal. The magnitude of the correlation between derivatives is measured to determine the presence of skew. Correlation between derivatives may be coupled with frequency offset information and/or with trials having additional positive and negative skew to determine presence of skew. Correlations are determined according to pre-defined time periods to provide for continued tracking and compensation for timing skew that may result from, for example, thermal drift.

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