Asymmetric compensation of polarization dependent loss in dual-polarization optical systems
AssigneeFujitsu Limited
InventorsOlga Vassilieva, Inwoong Kim, Jeng-Yuan Yang, Motoyoshi Sekiya
Life of this patent
Estimating the term…
Abstract
Methods and systems for asymmetrically compensating degradation of an optical signal-to-noise ratio (OSNR) induced by polarization dependent loss (PDL) in dual-polarization optical system include using an OSNR compensator. The OSNR compensator may separate the dual-polarization components and determine which component has degraded OSNR. The degraded component may be OSNR compensated using a phase-sensitive amplifier and/or a regenerator with a phase-sensitive amplifier.
Claims22
A method for compensating optical signal-to-noise ratio (OSNR) degradation in an optical network, comprising:
- receiving an optical signal having X- and Y-polarization components;
- rotating a polarization axis of the optical signal;
- separating the X- and Y-polarization components into an X-polarization optical signal transmission path and a Y-polarization optical signal transmission path;
- determining a degraded polarization component selected from the X-polarization component and the Y-polarization component based on degradation of an optical signal-to-noise ratio induced by polarization dependent loss;
- and
- restoring an optical signal-to-noise ratio of the degraded polarization component.
An optical signal-to-noise ratio compensator, comprising:
- a polarization controller for receiving a dual-polarized optical signal and rotating a state of polarization (SOP) of the dual-polarized optical signal;
- a polarization beam splitter for separating X- and Y-polarization components of the dual-polarized optical signal, respectively, along an X-polarization optical signal transmission path and a Y-polarization optical signal transmission path;
- two optical signal-to-noise monitors for respectively monitoring optical signal-to-noise ratios along the X-polarization optical signal transmission path and the Y-polarization optical signal transmission path;
- and
- a phase-sensitive amplifier for restoring an optical signal-to-noise ratio of a degraded polarization component selected from the X-polarization component and the Y-polarization component.
An optical communication system comprising:
- a transmitter that transmits a dual-polarized optical signal over an optical signal transmission path;
- a receiver that receives the dual-polarized optical signal from the optical signal transmission path;
- and
- at least one optical signal-to-noise ratio compensator, further comprising:
- a polarization controller for receiving the dual-polarized optical signal and rotating a state of polarization (SOP) of the dual-polarized optical signal;
- a polarization beam splitter for separating X- and Y-polarization components of the dual-polarized optical signal, respectively, along an X-polarization path and a Y-polarization path;
- two optical signal-to-noise monitors for respectively monitoring optical signal-to-noise ratios along the X-polarization path and the Y-polarization path;
- and
- a phase-sensitive amplifier for restoring an optical signal-to-noise ratio of a degraded polarization component selected from the X-polarization component and the Y-polarization component.
Dependencies are inferred from the claim text.