A telecommunications module includes an optical wavelength division multiplexer/demultiplexer configured to demultiplex a first optical signal input into the telecommunications module into a plurality of different wavelengths, a fiber optic splitter configured to split a second optical signal input into the telecommunication module into a plurality of optical signals, and a plurality of optical add/drop filters, each of the optical add/drop filters configured to combine one of the optical signals that has been split by the fiber optic splitter and one of the wavelengths that has been demultiplexed by the optical wavelength division multiplexer/demultiplexer into a combination output signal that is output from the telecommunications module.

Systems and methods include, responsive for a requirement to calibrate a single span in a multi-span optical line system where the single span includes a from-end node and a to-end node, determining no other upstream node in the multi-span optical multiplex section is currently calibrating or faulted; responsive to no other upstream node currently calibrating or faulted, calibrating the from-end node with a new target launch power into a fiber associated with the single span; and calibrating the to-end node keeping target launch power into a fiber associated with an immediate downstream span from the single span uninterrupted from a previous calibration. The to-end node and the from-end node are each (1) an intermediate line amplifier or (2) a terminal node and an intermediate line amplifier, in the multi-span optical line system.

Disclosed herein are methods and systems configuring a raman amplifier. One exemplary system may be provided with an optical amplifier deployed in an optical network, the optical amplifier having a plurality of raman pumps configured to obtain a desired gain profile. An actual gain profile and a raman pump configuration of each of the plurality of raman pumps may be processed by a network administration device using a first machine learning model to produce a combined optical transmission segment attribute representing attributes of an optical segment of the optical network. The combined optical transmission segment attribute and the desired gain profile may be processed with a second machine learning model to produce corrected raman pump configurations for each of the plurality of raman pumps of the raman amplifier. The corrected raman pump configurations may be used to configure each of the plurality of raman pumps of the raman amplifier.

Systems and methods for alien wavelength management. One embodiment is an apparatus for managing alien wavelengths for a Wavelength Division Multiplexing (WDM) system. The apparatus includes memory to store signal thresholds for alien wavelength signals transmitting over the WDM system, wherein the alien wavelength signals are generated by third-party equipment independently controlled from the WDM system. The apparatus also includes an Alien Wavelength Control Unit (AWCU) coupled between the third-party equipment and a channelization port of the WDM system, the AWCU configured to measure a signal parameter of an alien wavelength signal transmitted by the third-party equipment to the channelization port. The apparatus further includes a controller coupled with the AWCU and configured, in response to determining that the signal parameter is outside a signal threshold of the WDM system, to direct the AWCU to modify the alien wavelength signal to protect the WDM system.

Systems and methods for alien wavelength management. One embodiment is an apparatus for managing alien wavelengths for a Wavelength Division Multiplexing (WDM) system. The apparatus includes memory configured to store assigned frequency spectrums of corresponding destination third-party equipment for receiving alien wavelength signals, wherein the alien wavelength signals are generated by source third-party equipment independently controlled from the WDM system. The apparatus also includes an Alien Wavelength Control Unit (AWCU) coupled between one or more channelization ports of the WDM system and one or more destination third-party equipment, and a controller configured to direct the AWCU to filter the alien wavelength signal based on the assigned frequency spectrums, wherein the filter transmits the alien wavelength signal to a destination third-party equipment corresponding with an assigned frequency spectrum.

A multi-channel sensing system is disclosed. The multi-channel sensing system includes a multi-channel sensor connector that wavelength-divides an optical pulse output from a pulsed laser into a plurality of channels in a spectrum domain, transmits each of a plurality of optical sub-pulses generated from the wavelength division to a channel path allocated for each channel in multi-channel paths, multiplexes the plurality of optical sub-pulses passed through the multi-channel paths and outputs an optical signal including the multiplexed optical sub-pulses; and a multi-channel optical phase detector that receives the optical signal output from the multi-channel connector and a reference signal which is synchronized to the pulse laser, and detects a channel-specific electrical signal that corresponds to a timing error between each of the plurality of optical sub-pulses included in the optical signal and the reference signal. At lease one of sensors is connected to at least one of the multi-channel paths.

The technology employs a state-based power control loop (PCL) architecture to maintain tracking and communication signal-to-noise ratios at suitable levels for optimal tracking performance and data throughput in a free-space optical communication system. Power for a link is adjustable to stay within a functional range of receiving sensors in order to provide continuous service to users. This avoids oversaturation and possible damage to the equipment. The approach can include decreasing or increasing the power to counteract a surge or drop while maintaining a near constant received power at a remote communication device. The system may receive power adjustment feedback from another communication terminal and perform state-based power control according to the received feedback. This can include re-initializing and reacquiring a link with the other communication terminal automatically after loss of power, without human intervention. There may be a default state and discrete states including rain, fade, surge and unstable states.

A cyclic wavelength band permutation device (31) includes as many wavelength band converters (32a to 32c) as the wavelength bands of optical signals (S1, C1, and L1), and the wavelength band converters are individually connected to the output terminals of corresponding optical amplifiers among a plurality of optical amplifiers (17a to 17c) connected to an optical fiber (16) in an inserted manner. When a wavelength-multiplexed signal beam obtained by multiplexing optical signals in different wavelength bands is multiband-transmitted through an optical fiber while being amplified by the plurality of optical amplifiers, each wavelength band converter performs a cyclic permutation process of transitioning or converting an optical signal allocated to the shorter wavelength band side in the bands of the optical fiber to the longer wavelength band side, and also transitioning or converting an optical signal allocated to the longest wavelength band to the shortest wavelength band.

A node (10) includes multiplexing unit (11) that multiplexes a plurality of subcarrier signals for performing optical wavelength multiplexing communication into a wavelength group signal; output unit (12) that outputs the multiplexed wavelength group signal to an optical transmission line; pre-multiplexing level correction unit (13) that corrects a level deviation between the subcarrier signals before the multiplexing based on an optical level of the wavelength group signal in the output unit (12); and post-multiplexing level correction unit (14) that corrects a level deviation of the wavelength group signal after the multiplexing including the corrected subcarrier signals based on the optical level of the wavelength group signal in the output unit (12).

There is provided a method, apparatus and system for determining multipath interference (MPI) in optical communications. It is object of embodiments of the present disclosure to provide an effective, low-cost way of detecting or measuring MPI. To effectively detect and measure the MPI, multiple zero-power gaps are inserted into the transmission signal (optical signal) in time domain. In some embodiments, at least some of the zero-power gaps inserted in the main signal do not overlap the zero-power gaps of the reflection of the main signal. Using the zero-power gaps contained the main signal and the reflection (where applicable), power inside and outside the zero-power gaps are determined. Then, the strength of the MPI is determined based on the determined power inside and outside the zero-power gaps.