Stokes-vector-based transmission and detection of optical polarization-division-multiplexed signals

摘要

We disclose an optical transport system configured to transport data using a PDM-modulation format, in which each of two orthogonal polarizations is independently amplitude-modulated, and the relative phase between the carrier waves of the two polarizations may also be modulated. This modulation format enables the optical receiver to perform direct optical detection using a Stokes-vector detector to fully recover the encoded data. In an example embodiment, the corresponding signal processing at the optical receiver may include: determining a Stokes-space rotation matrix corresponding to the polarization-state rotation encountered by the PDM signal in the optical transport link; applying the determined Stokes-space rotation matrix to the Stokes sub-vector measured by the Stokes-vector detector to estimate the Stokes sub-vector of the PDM signal at the originating optical transmitter; converting the estimated Stokes sub-vector into the corresponding Jones vector; and recovering the data by decoding the polarization components of the Jones vector.

主权项

1. An apparatus comprising:
an optical detector that includes a polarization splitter configured to split an optical polarization-division-multiplexed (PDM) signal into two light beams and an optical-to-electrical converter configured to generate first, second, and third electrical signals by optically detecting different combinations of light of the two light beams, the first, second, and third electrical signals being measurements of three nontrivial components of a Stokes vector of the optical PDM signal or linearly independent combinations of said three nontrivial components; and a digital signal processor configured to receive the first, second, and third electrical signals from the optical detector and generate therefrom an estimate of first data carried by a first polarization of the optical PDM signal and second data carried by a different second polarization of the optical PDM signal.