A communication system includes a first optical system and a second optical system optically connected to a clamping laser and a pump laser. The first optical system includes first and second optical splitters. The first optical splitter is configured to receive a clamping laser signal from the clamping laser and split the signal into split clamping laser signals. The second optical splitter is configured to receive a pump laser signal from the pump laser and split signal into split pump laser signals. The second optical system is optically connected to the first optical system and includes amplifier systems. Each amplifier system is configured to receive a multiplexed signal. The second optical system includes first and second combiners optically connected to an erbium-doped fiber. The first combiner is optically connected to the first splitter, and the second combiner is optically connected to the second splitter.

Example embodiments of the present invention relate to an optical signal processor comprising of at least one wavelength processing device, a plurality of optical amplifying devices, and a least one field programmable photonic device.

The present invention discloses a method and a controller for commissioning a wave division multiplexing optical network during capacity expansion. The method includes: calculating, according to a preset rule, initial power of a wavelength service to be added and adding one or more wavelength services according to the initial power; detecting power of each newly-added wavelength service in transmission and separately calculating target power of each newly-added wavelength service according to a detected value and the initial power; calculating end-to-end performance of an existing wavelength service and end-to-end performance of each newly-added wavelength service when each newly-added wavelength service reaches its respective target power; and adjusting the power of each newly-added wavelength service when each newly-added wavelength service reaches its respective target power and the end-to-end performance of the existing wavelength service and the end-to-end performance of each newly-added wavelength service meets their respective lowest threshold requirements.

An active optical combiner for a CATV network.

This spatial division multiplexing (SDM) in power-limited optical communication systems. In general, an SDM optical transmission system may be configured to increase data capacity over the data capacity of a non-SDM optical transmission system while maintaining power consumption at or below that of the existing non-SDM optical transmission system. To realize such an improvement in performance without increasing power consumption, an example SDM optical transmission may be constructed by reducing system bandwidth, reducing and/or altering equipment for filtering, reducing optical amplifier spacing, reducing operational amplifier power consumption, etc. In this manner, increased data transmission performance may be realized even where available power may be strictly limited.

A characteristic measurement device that measures a characteristic between lanes of a transmitter and a receiver connected via an optical fiber transmission path, the characteristic measurement device including an adaptive equalization unit that uses a polarization multiplexed reception signal and a phase conjugate signal of the polarization multiplexed reception signal or a plurality of signals mathematically equivalent to the reception signal and the phase conjugate signal of the reception signal as input signals and performs equalization processing on the input signals, and a characteristic function derivation unit that calculates a first inverse characteristic representing an inverse characteristic of the transmitter and a second inverse characteristic representing an inverse characteristic of the receiver on the basis of a filter coefficient obtained at the time of the equalization processing performed by the adaptive equalization unit and a frequency offset.

An apparatus includes an optical power supply including: a power supply light source configured to generate power supply light; at least one optical input/output port; at least one photodetector; and a coupling module. The coupling module is configured to receive the power supply light from the power supply light source and output the power supply light through the optical input/output port, receive reflected light through the optical input/output port, and transmit the reflected light to the photodetector. The photodetector is configured to detect the reflected light and generate a signal representing a level of the reflected light. The optical power supply includes a controller that is configured to compare the level of the detected reflected light with a threshold value, and upon determining that the level of the detected reflected light is less than the threshold value, reduce or turn off the power supply light that is provided to the optical input/output port.

To provide an optical transport device that enable the strengths of optical signals to be recovered when the strengths of the optical signals vary, an optical transmission device comprises: a wavelength selection switch that attenuates, in accordance with an attenuation amount, each of a plurality of optical signals outputted from a plurality of optical transmitter, multiplexes and outputs the attenuated optical signals; and an optical detector that detects and compares the strength of at least one of the plurality of optical signals with a first threshold value and a second threshold value higher than the first threshold value. On the basis of the result of said comparison, the wavelength selection switch controls the attenuation amount such that the optical signal the strength of which has been detected has a strength value between the first threshold value and the second threshold value.

Techniques are presented herein to set power levels for multiple Raman pump wavelengths in a distributed Raman amplification configuration. A first receive power measurement is obtained at a second node with a controlled optical source at a first node turned on and with a plurality of Raman pump lasers at different wavelengths at the second node turned off. A second receive power measurement is obtained at the second node with the controlled optical source at the first node turned on and the plurality of Raman pump lasers turned on to respective reference power levels to inject optical Raman pump power at a corresponding plurality of wavelengths into the optical fiber span. Based on a target Raman gain and a target Raman gain tilt, respective ratios of a total power are obtained, each ratio to be used for a corresponding one of the plurality of Raman pump lasers.

An optical transmission apparatus includes: a variable optical attenuation section configured to independently adjust, for each wavelength, attenuation of light of a plurality of wavelengths and adjust output optical power of wavelength multiplexed light that is output to an optical transmission line by adjustment of the attenuation; and a control section configured to stop, in accordance with control in which a wavelength included in the wavelength multiplexed light in a first wavelength band is wavelength-shifted to a second wavelength band that is different from the first wavelength band, adjustment of attenuation performed on the first wavelength band by the variable optical attenuation section.