It is difficult to flatten the gain profile of an optical amplifier without increasing the power consumption, the cost, and the size of the optical amplifier; therefore, a monitoring apparatus for optical amplifier according to an exemplary aspect of the invention includes an optical filtering means for receiving a monitor light beam of the optical amplifier and transmitting a filtered monitor light beam with a set range of wavelength band; a photoelectric conversion means for converting the filtered monitor light beam into a monitoring signal; and a spectrum information generating means for generating spectrum information based on the monitoring signal, the spectrum information including information on a spectrum profile of output of the optical amplifier.

Optical amplifier apparatus (100) comprising: an input (102) for an incoming optical signal (IN) comprising an optical supervisory channel, OSC, signal and service channel signals at channel wavelengths of a WDM channel wavelength grid; an output (112) for an outgoing optical signal (OUT); an optical amplifier, OA, (106) having an operating bandwidth including the WDM channel wavelength grid; a first optical drop filter (104) configured to drop from an IN signal an out-of-band, OOB, OSC signal at a wavelength outside the OA operating bandwidth; a second optical drop filter (108, 208) configured to drop from an IN signal an in-band, IB, OSC signal at a wavelength within the OA operating bandwidth; an OSC signal output (114) configured to output the dropped OSC signal; an OSC signal input (116) configured to receive an outgoing OOB OSC or IB OSC signal; and an optical add filter (110, 210) configured to add an outgoing OOB OSC or IB OSC signal to service channel signals at channel wavelengths of the WDM channel wavelength grid to form the OUT signal.

A system and method consistent with the present disclosure provides for automated line monitoring system (LMS) baselining that enables capturing and updating of operational parameters specific to each repeater and associated undersea elements based on high loss loopback (HLLB) data. The captured operational parameters may then be utilized to satisfy queries targeting specific undersea elements in a Command-Response (CR) fashion. Therefore, command-response functionality may be achieved without the added cost, complexity and lifespan issues related to deploying undersea elements with on-board CR circuitry. As generally referred to herein, operational parameters include any parameter that may be derived directly or indirectly from HLLB data. Some example non-limiting examples of operational parameters include span gain loss, input power, output power, gain, and gain tilt.

A system and method for automatically calibrating loopback data in a line monitoring system of an optical communication system. Extra peaks in loopback data are calibrated out of the loopback data used by the system by identifying pairs of peaks in the loopback data associated with test signal transmissions through the same high loss loopback path from opposite ends of the optical transmission path.

A system and method consistent with the present disclosure provides for automated line monitoring system (LMS) baselining that enables capturing and updating of operational parameters specific to each repeater and associated undersea elements based on high loss loopback (HLLB) data. The captured operational parameters may then be utilized to satisfy queries targeting specific undersea elements in a Command-Response (CR) fashion. Therefore, command-response functionality may be achieved without the added cost, complexity and lifespan issues related to deploying undersea elements with on-board CR circuitry. As generally referred to herein, operational parameters include any parameter that may be derived directly or indirectly from HLLB data. Some example non-limiting examples of operational parameters include span gain loss, input power, output power, gain, and gain tilt.

Provided is a technology for simultaneously monitoring a plurality of relay devices. A relay device 1 comprises a superimposing unit 2 and a monitor unit 3. The relay device 1 is interposed on an optical transmission path between optical communication devices that send and receive an optical signal, and has a function for relaying the optical signal flowing through the optical transmission path. The monitor unit 3 monitors the operation status of the relay device 1. At a predetermined timing, the superimposing unit 2 superimposes monitor unit 3 monitoring-information onto an optical signal of a primary signal flowing through the optical transmission path, by performing modulation processing on the basis of an oscillation signal having a predetermined oscillation frequency. The relay device 1 can spontaneously superimpose the monitoring information onto an optical signal and transmit same.

A method of training a machine learning system to determine operating parameters for optical transceivers includes connecting the transceiver to a test and measurement device, tuning the transceiver with a set of parameters, capturing a waveform from the transceiver, sending the waveform and the set of parameters to a machine learning system, and repeating the tuning, capturing, and sending until a sufficient number of samples are gathered.

A regenerative relay transponder includes: an optical receiving unit that receives an optical signal from a transmitting device as a reception optical signal and converts the reception optical signal into an electrical signal; an electrical-signal processing unit that executes predetermined processing on the electrical signal; an optical transmitting unit that generates a transmission optical signal by converting the electrical signal subjected to the predetermined processing into an optical signal and transmits the transmission optical signal; and a monitoring unit that monitors the predetermined processing by the electrical-signal processing unit, wherein the monitoring unit accumulates in a storage unit monitoring data, which indicates the result of the monitoring, over a predetermined period and causes a communication unit to transmit the monitoring data accumulated over the predetermined period as transmission data to the transmitting device.

In some examples, a network device comprises one or more processors operably coupled to a memory, and a routing unit configured for execution by the one or more processors to route data traffic on a layer 3 network overlaying an optical transport system; receive optical supervisory channel data for an optical supervisory channel of the optical transport system; determine the optical supervisory channel data indicates an event affecting transmission or detection of a signal transported by a wavelength, the wavelength traversing an optical fiber of the optical transport system and underlying a link of the layer 3 network; and reconfigure, in response to determining the optical supervisory channel data indicates the event, a configuration of the network device to modify routing operations of the network device with respect to the data traffic on the layer 3 network.

Provided is a signal loopback circuit which, in order to loop back a monitoring signal in a relay device for relaying optical signals of a plurality of wavelength bands, connects between a channel of first direction and a channel of second direction through which an optical signal of first wavelength band and an optical signal of second wavelength band are transmitted, wherein the signal loopback circuit is provided with a first coupler for branching the optical signal on the channel of first direction, a first filter for extracting at least one of a monitoring signal of first wavelength band and a monitoring signal of second wavelength band that are used in the channel of first direction from the optical signal branched by the first coupler, and a second coupler for causing the monitoring signal extracted by the first filter to be joined to the channel of the second direction.