Integrated polarimeter in an optical line system

A polarimeter system for use in an optical line system, the polarimeter system comprising:

• a first optical line device located at a first node, including a first transmitter connected to a first fiber and a first polarimeter receiver connected to a second fiber, the first optical line device comprising an Optical Supervisory Channel (OSC);
• a second optical line device located at a second node, including a second transmitter connected to the second fiber and a second polarimeter receiver connected to the first fiber, the second optical line device comprising an Optical Supervisory Channel (OSC);
• wherein the first transmitter and the second transmitter are configured to transmit a polarization probe signal at an associated wavelength outside of a band of wavelengths used for traffic-bearing channels in the optical line signal, and
• wherein the first polarimeter receiver and the second polarimeter receiver are each configured to receive the associated polarization probe signal and derive a measurement of State of Polarization (SOP) on the corresponding fiber based thereon, and the wavelength of the associated polarization probe signal is outside of the C-band, greater than 1500 nm to avoid any Raman pump lasers, and different from wavelengths for OSCs, and wherein the polarimeter receiver only projects SOP on half of a Poincare sphere.

A pluggable module for use in an optical line system, the pluggable module comprising:

• a transmitter connected to the transmit fiber via an output port of the pluggable module, wherein the transmitter is configured to transmit a polarization probe signal at a wavelength outside of a band of wavelengths used for traffic-bearing channels in the optical line signal, to a second polarimeter receiver at a second pluggable module;
• and
• a polarimeter receiver connected to a receive fiber via an input port of pluggable module, wherein the polarimeter receiver is configured to receive a second polarization probe signal from a second transmitter transmitted from the second pluggable module and to derive a measurement of State of Polarization (SOP) on the receive fiber based on the second polarization probe signal;
• wherein the pluggable module is configured to be plugged into the optical line system to support dual Optical Time Domain Reflectometer (OTDR) and polarimeter functionality based on configuration.