Methods and systems for implementing a low noise CDC ROADM include incorporating individual stages of an optical PSA before and after WSSs included in the CDC ROADM. The WSSs may be used to route the pump and idler signals, as well as to perform phase tuning for optimal phase-sensitive amplification.

Methods and systems for implementing a low noise CDC ROADM include incorporating individual stages of an optical PSA before and after WSSs included in the CDC ROADM. The WSSs may be used to route the pump and idler signals, as well as to perform phase tuning for optimal phase-sensitive amplification.

An optical transmission device includes: a first optical amplifier, a WSS (wavelength selective switch), a second optical amplifier and a controller. The first optical amplifier amplifies a received WDM (wavelength division multiplexed) optical signal. The WSS controls optical powers of respective channels multiplexed in the WDM optical signal that is amplified by the first optical amplifier. The second optical amplifier amplifies the WDM optical signal output from the WSS. The controller controls a gain of the first optical amplifier based on initial setting information. The controller corrects the gain of the first optical amplifier such that an average optical power of a plurality of channels multiplexed in the WDM optical signal that is amplified by the first optical amplifier approaches a target level after a specified period of time has elapsed from when the gain of the first optical amplifier is controlled based on the initial setting information.

In some aspects, the techniques described herein relate to a method that includes: obtaining optical channel spectrum data that includes amplified spontaneous emission data and channel data associated with optical signals propagated through an optical fiber; fitting an amplified spontaneous emission trend to the amplified spontaneous emission data; fitting a channel trend to the channel data; jointly optimizing the amplified spontaneous emission trend and the channel trend to determine an optimized channel trend; and determining an anomaly in the channel data based upon the optimized channel trend.

A bidirectional optical amplifier amplifies optical signals having signal wavelength and signal power input from two directions. The amplifier is arranged so that two counter-propagating signals pass through a first pumped rare earth doped pre-amplifier before passing through other amplifiers downstream. Optical circulators route the two counter propagating signals so that they both pass through in a counter-propagating manner through subsequent pumped rare earth doped amplifiers downstream.

An optical transmission apparatus may include a coherent detector, a photoelectric converter, an amplifier, a gain controller, and an optical power monitor. The coherent detector may perform a coherent detection on received light including a plurality of wavelengths to select light having any one of the wavelengths. The photoelectric converter may convert the light having the selected wavelength to an electrical signal. The amplifier may amplify the electrical signal. The gain controller may control a gain of the amplifier depending on an output amplitude of the amplifier. The optical power monitor may calculate an optical power level of the selected wavelength based on the gain and the output amplitude.

An optical relay device includes a WSS functioning as a wavelength selective switch capable of performing path switching in wavelength units and optical level adjustment for each of wavelengths and a control device that instructs, on the basis of a fluctuation amount of an optical level for each of the wavelengths of an optical signal output from the WSS and setting information indicating, for each of the wavelengths, whether optical level adjustment for the wavelengths of the optical signal is enabled, the WSS to perform a setting change of an optical level adjustment amount of the optical signal.

Described herein are photonic integrated circuits (PICs) comprising a semiconductor optical amplifier (SOA) to output a signal comprising a plurality of wavelengths, a sensor to detect data associated with a power value of each wavelength of the output signal of the SOA, a filter to filter power values of one or more of the wavelengths of the output signal of the SOA, and control circuitry to control the filter to reduce a difference between a pre-determined power value of each filtered wavelength of the output signal of the SOA and the detected power value of each filtered wavelength of the output signal of the SOA.

An optical transmission device includes: a wavelength allocation detector configured to detect wavelength allocation that indicates allocation of optical signals multiplexed in a WDM optical signal; a power adjusting unit configured to adjust powers of the optical signals multiplexed in the WDM optical signal; an optical amplifier configured to amplify the WDM optical signal output from the power adjusting unit; a power controller configured to generate a power control signal to control the power adjusting unit such that the WDM optical signal has a specified wavelength characteristic; and a correction value generator configured to generate a correction value to correct the power control signal based on the wavelength allocation. The power controller corrects the power control signal with the correction value. The power adjusting unit adjusts powers of the optical signals multiplexed in the WDM optical signal according to the corrected power control signal.

There is provided an optical transmission control device includes a memory, and a processor coupled to the memory and the processor configured to aggregate information of candidacy sections having a possibility that communication is discontinued among wavelength-multiplexed transmission sections, classify, based on the aggregated information, optical paths set between optical transmission devices into a first optical path on which, when communication in the candidacy sections is discontinued, an optical signal is not transmitted, and a second optical path on which, when the communication in the candidacy sections is discontinued, an optical signal is transmitted, and determine a wavelength allocation in a first wavelength group of the first optical path and a second wavelength group of the second optical path so that a difference in gain wavelength characteristics of the first optical path and the second optical path is equal to or less than a predetermined level.