US 8,045,856 B2 · Polarization mode dispersion compensation and polarization demultiplexing systems and methods for optical transmission systems

Abstract

The present disclosure provides polarization mode dispersion compensation (PMDC) and polarization de-multiplexing systems and methods for polarization multiplexed (PolMux) optical transmission systems. The PMDC detects an error signal before a polarization splitter in PolMux systems for controlling polarization controllers (PC) and/or DGDs in the PMDC for return-to-zero (RZ) differential m-phase shift keying (DmPSK) signals. For bit-aligned PolMux systems, the error signal could be the level of clock frequency at one, two, or more times of the baud rate at one polarization. For bit-interleaved PolMux systems, the error signal could be the level of clock frequency at two times of the baud rate at one polarization. The PMDC can operate in PolMux systems with any arbitrary time offset between the two polarizations. The polarization de-multiplexer utilizes error detection at both output arms of a polarization splitter to mitigate PDL impact on any PolMux type of signal.

Claims16

Dependent claims

A polarization mode dispersion compensator for polarization multiplexed Return-to-Zero signals, comprising:

a polarization control mechanism;
a tap located after the polarization control mechanism and before a polarization splitter;
an error detection circuit connected to the tap;
and
a control circuit configured to control the polarization control mechanism responsive to an error signal from the error detection circuit;
wherein the error signal comprises one of a level of a basic clock frequency at a baud rate or at two or more times the baud rate at one polarization for bit-aligned polarization multiplexed systems and a level of a basic clock frequency at a two times the baud rate at one polarization for bit-interleaved polarization multiplexed systems;
and
wherein the error detection circuit is configured to detect the error signal.

5 more elements

A polarization mode dispersion compensator for polarization multiplexed Return-to-Zero differential m-phase shift keying signals with arbitrary time offsets between polarizations, comprising:

a polarization control mechanism;
a tap located after the polarization control mechanism;
a delay mechanism connected to the tap, wherein the delay mechanism is configured to compensate for the arbitrary time offsets between polarizations;
an error detection circuit connected to the delay mechanism;
and
a control circuit configured to control the polarization control mechanism responsive to an error signal from the error detection circuit signal;
wherein the error signal comprises the level of the basic clock frequency at the baud rate at one polarization;
and
wherein the error detection circuit is configured to detect the error signal.

6 more elements

Dependencies are inferred from the claim text.

Polarization mode dispersion compensation and polarization demultiplexing systems and methods for optical transmission systems

Life of this patent

Polarization mode dispersion compensation and polarization demultiplexing systems and methods for optical transmission systems

Life of this patent

Abstract

Claims16