Measuring signal to noise ratio of a WDM optical signal

摘要

A device for measuring optical signal-to-noise ratio (OSNR) of a wavelength division multiplexing (WDM) optical signal including multiple wavelength channels may include a tunable optical filter to select an optical wavelength channel of the plurality of optical wavelength channels. The device may also include a polarization controller to adjust a polarization state of the selected optical wavelength channel, and a control unit to compute the OSNR of the selected wavelength channel based on a target control point.

主权项

1. A device to determine optical signal-to-noise ratio (OSNR) of a wavelength division multiplexing (WDM) optical signal including a plurality of optical wavelength channels, the device comprising:
a tunable optical filter to select an optical wavelength channel of the plurality of optical wavelength channels; a polarization controller to adjust a polarization state of the selected optical wavelength channel; and a control unit to iteratively search for a target control point of the polarization controller wherein a first optical power level of the selected optical wavelength channel is minimized, and to compute the OSNR of the selected optical wavelength channel based on the target control point, wherein the iterative search for the target control point comprises:
determining initial control points and optical power measurements for the initial control points in a first iteration;determining a plurality of control points in a second iteration based on the optical power measurements determined for the initial control points; anddetermining the target control point based on optical power measurements determined for the plurality of control points.