Patent ID: 9485019
Filing Date: 2016-11-01
CPC Classification: H04B,H04J

Claim Text:
1. A method for optical channel monitoring of dual polarization signals, the method comprising: receiving, from the optical transport network, optical subcarriers transmitted by the optical transport network, including a first optical subcarrier modulated at a first optical frequency with carrier data using an X polarization component and a Y polarization component and modulated at a first modulation frequency that is less than the first optical frequency, wherein the X polarization component and the Y polarization component are modulated using complementary phase at the first modulation frequency; scanning the optical subcarriers using a periodic optical filter over a free optical spectral range of the periodic optical filter to generate a filtered signal; determining states of polarization of the filtered signal, including generating normalized Stokes vector signals (S based on the normalized Stokes vector signals (S based on the first Stokes vector, demodulating the filtered signal within the free spectral range to generate a first power spectrum and a second power spectrum for the first modulation frequency, wherein the first power spectrum corresponds to the X polarization component and the second power spectrum corresponds to the Y polarization component; and based on at least one of the first power spectrum and the second power spectrum, identifying a center optical frequency of the first optical subcarrier received.