Methods and systems for using modulation frequencies for optical channel monitoring with periodic optical filtering

摘要

Methods and systems for using modulation frequencies for optical channel monitoring with periodic optical filtering may allocate modulation frequencies based on bandwidth slices of an optical spectrum. The bandwidth slices may have an equal spectral band that is associated with a respectively unique modulation frequency. An optical carrier aligning with a bandwidth slice may be modulated using the modulation frequency assigned to that bandwidth slice. Additionally, the bandwidth slices may be used to determine a maximum frequency error of an optical carrier when received, such as from frequency drift during transmission.

主权项

1. A method for using modulation frequencies, the method comprising:
dividing an optical band into bandwidth slices, each of the bandwidth slices having an equal spectral band that is smaller than a minimum optical carrier bandwidth; assigning, to each of the bandwidth slices, a modulation frequency that is respectively unique to each of the bandwidth slices; based on a spectral position of a first bandwidth slice, assigning a first optical carrier aligned with the spectral position to a first modulation frequency corresponding to the first bandwidth slice; transmitting the first optical carrier over an optical transport network, including modulating the first optical carrier using the first modulation frequency, wherein the first optical carrier is included with a plurality of optical carriers transmitted over the optical transport network; receiving, from the optical transport network, the optical carriers transmitted; scanning the optical carriers using a periodic optical filter over a free optical spectral range Wfs of the periodic optical filter to generate a filtered signal, wherein the free optical spectral range Wfs corresponds to K number of optical carriers, and wherein K is greater than or equal to 2; demodulating the filtered signal to generate a power spectrum within the free spectral range for the first modulation frequency; and based on the first bandwidth slice and the power spectrum for the first modulation frequency, identifying a first center optical frequency of the first optical carrier received.