Fujitsu Corporation

Hiroki Oi

Shoichiro Oda

Yasuhiko Aoki

Takeshi Hoshida

Hisao Nakashima

Takafumi Terahara

Goji Nakagawa

Norifumi Shukunami

Kosuke Komaki

Satoru Okano

Takehiro Fujita

Tatsuya Tsuzuki

Jeng-Yuan Yang

Shigeru Ishii

Tomohiro Kaneoka

Yoichi Akasaka

An optical transmission system includes a first optical node, a second optical node, and an optical fiber provided between the first optical node and the second optical node. The optical transmission system further includes: a signal generator provided in the first optical node and configured to generate an optical signal including a plurality of wavelength channels and an empty channel; an optical transmission circuit provided in the first optical node and configured to output the optical signal to the optical fiber; an optical channel monitor provided in the second optical node and configured to measure reception power of each channel in the optical signal received through the optical fiber; and a processor configured to determine a type of the optical fiber based on the reception power of the empty channel, the reception power being measured by the optical channel monitor.

Optical transmission system and fiber type determination method

A transmission apparatus includes a demultiplexer configured to demultiplex a multiplexed signal including wavelength multiplexed signals having individual wavelength bands into a wavelength multiplexed signal for each of the wavelength bands, a detector configured to detect a power value of each of the wavelength multiplexed signals for each of the wavelength bands, first compensators configured to compensate for a tilt in the wavelength multiplexed signal based on the power value for each of the wavelength bands, second compensators configured to compensate for a power of the wavelength multiplexed signal for each of the wavelength bands so as to reduce a power difference among wavelength multiplexed signals after the tilt compensation based on the power value for each of the wavelength bands, and a multiplexer configured to multiplex each of the wavelength multiplexed signals after the power compensation and output a multiplexed signal.

Optical wavelength multiplexing transmission apparatus and optical wavelength multiplexing transmission method

A network controller includes: a first acquisition unit configured to acquire, based on a signal quality amount of each of wavelength paths set in a network of an optical wavelength-multiplexed transmission system, a signal quality amount of each of spans in each of the wavelength paths; an arithmetic unit configured to calculate a signal quality amount of each of spans in a wavelength path of an estimation target, based on the signal quality amount acquired by the first acquisition unit; and an estimation unit configured to estimate a signal quality amount of the wavelength path of the estimation target, based on the signal quality amount calculated by the arithmetic unit.

Network controller and signal quality estimating method

An optical signal-to-noise ratio monitor includes: a measuring unit that measures an optical signal-to-noise ratio of a polarization multiplexed optical signal, a polarization state of the polarization multiplexed optical signal changing with respect to time; a selector that selects, from a plurality of optical signal-to-noise ratios measured by the measuring unit at a plurality of measurement points within a designated measurement period, an optical signal-to-noise ratio that is higher than an average of the plurality of optical signal-to-noise ratios; and an output unit that outputs the optical signal-to-noise ratio selected by the selector.

Optical signal-to-noise ratio monitor and method for measuring optical signal to-noise ratio

A transmission device includes: optical transmitters configured to transmit optical signals of different wavelengths; optical couplers configured to multiplexing the optical signals transmitted from the optical transmitters; and a wavelength selective switch configured to multiplex multiplexed optical signals obtained by multiplexing by the couplers, wherein optical signals, a wavelength interval between which is less than a predetermined value, are transmitted to separate optical couplers of the optical couplers, among the optical signals.

Transmission device and transmission method

An optical transmission device including a wavelength selective switch including plural output ports, an optical intensity monitoring device that receives each optical signal output from the plural output ports of the wavelength selective switch and monitors the optical intensity of the optical signals, and a controller that controls optical intensity of the optical signals from the plural output ports of the wavelength selective switch based on the optical intensities monitored by the optical intensity monitoring device.

Optical transmission device

An optical branching and insertion device includes an optical splitter that branches an input optical signal, and outputs the branched optical signal from a first output port and a second output port; a wavelength selective switch that allows passage of an optical signal of a predetermined wavelength from among optical signals input to a first input port from the first output port, and outputs the optical signal of the predetermined wavelength and an optical signal inputted from a second input port; and a processor that executes a process to expand a band through which the optical signal of the predetermined wavelength is allowed to pass, the process being executed when a channel allocated to a wavelength of the optical signal inputted from the second input port and a channel allocated to the predetermined wavelength are not adjacent.

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Kawasaki, Japan

Hiroki Oi