Fujitsu Corporation

Fujitsu Network Communications, Inc.

Yokogawa Electric Corporation

Hitachi Cable, Inc.

Fujitsu Telecom Networks Limited

Fujistu Limited

Takeshi Hoshida

Hisao Nakashima

Takahito Tanimura

Yuichi Akiyama

Shoichiro Oda

Takafumi Terahara

Tomoyuki Kato

Tomofumi Oyama

Kazuo Hironishi

Hiroki Ooi

Kentaro Nakamura

Tomoo Takahara

Shigeki Watanabe

Toshiki Tanaka

Akira Miura

Hiroshi Onaka

Yasuhiko Aoki

Jens Rasmussen

Yi Ge

Yoshitaka Nomura

Seemant Choudhary

Zhenning Tao

Olga I Vassilieva

Toru Katagiri

Goji Nakagawa

Tomohiro Yamauchi

Masato Nishihara

Setsuo Yoshida

Naoki Kuwata

Rainer Hainberger

Lei Li

Hideyuki Miyata

Tomoyuki Akiyama

Shinsuke Tanaka

Kyosuke Sone

Masahiro Yuki

Guoxiu Huang

Tadashi Ikeuchi

George Ishikawa

Yutaka Kai

Kazuyuki Tajima

Nobukazu Koizumi

Youichi Akasaka

Yoshio Hirose

Weizhen Yan

Osamu Takeuchi

Koji Nakamuta

Akihiko Isomura

Hiroki Oi

Noriyasu Nakayama

Yoshinori Nishizawa

Motoyoshi Sekiya

Yasuyuki Suzuki

Yasushi Sugaya

Paparao Palacharla

Inwoong Kim

Nobuhiro Fukushima

Norifumi Shukunami

Hiroyuki Matsuura

Ying Zhao

Kosuke Komaki

Tamotsu Akashi

Liang Dou

Shota Mori

Hiroshi Nakamoto

Morio Wada

Ryosuke Goto

Noriaki Mizuguchi

Yasuhiro Nakasha

Jun Matsui

Taku Saito

Ling Liu

Masaaki Kawai

Yoshio Sakai

Hideaki Arai

Katsumi Fukumitsu

Takashi Toyomaki

Kiichi Sugitani

Shingo Hara

Hideyuki Matsuura

Toshiki Honda

Huijian Zhang

Kazunari Shiota

Eiji Ishikawa

Hiroyuki Irie

Kenichi Kaburagi

Daijiro Tanaka

Kaori Odate

Yoshikazu Terayama

Satoshi Takasugi

Rémi R Pecqueur

Yu Tanaka

Hikari Mochizuki

Gerardo Antonio Castañón

Rafael Puerta Ramirez

Hiroki Satou

Olga Vassilieva

Jens C Rasmussen

An optical communication element includes a plurality of slabs, an input port group, an output port group, a first waveguide group, and a second waveguide group. The plurality of slabs includes third waveguide. Each of the plurality of slabs include a predetermined number of first ports being arranged at an inlet the third waveguide at equal intervals in a lateral direction perpendicular to a light traveling direction, and input the optical signals, and a predetermined number of second ports being arranged at an outlet of the third waveguide at the equal intervals in the lateral direction so as to face the first ports, and output the optical signals. Each of the third waveguides are configured with a dimension that allows light intensity to be distributed at all traveling positions located in the lateral direction.

Optical communication element and optical neural network

An optical analog-to-digital (AD) converter includes, wherein the optical AD converter converts an analog signal of information included in inputted signal light into a digital signal, and is formed of N stages corresponding to a number N of bits of the digital signal, optical waveguides configured to respectively guide the signal light, base light obtained by branching local light, and reference light obtained by branching the local light, a light receiver configured to detect and compare light levels of the signal light and the reference light, and output a binary comparison result, and an optical modulator configured to variably control a light level of the base light, based on the binary comparison result, in each stage of the N stages, wherein an output variably controlled of the optical modulator is multiplexed with the reference light of a next stage.

Optical AD converter and optical receiver

An optical demultiplexing device includes a light source, a demultiplexer, a plurality of converters, a detector, a switch, and a controller, wherein the demultiplexer includes a plurality of asymmetric Mach-Zehnder interferometers (AMZ) each of which lengths of a pair of arms are different from each other, the plurality of AMZs are coupled to each other so that a plurality of wavelength lights input from the light source is demultiplexed and respectively output to the converters different from each other, and the controller controls the light source so that the plurality of wavelength lights is sequentially input to the demultiplexer one by one, and controls the switch so that an electrical signal detected by the detector is output to an output destination according to a wavelength light of a conversion source of the electrical signal.

Optical demultiplexing device and transmission device

An optical transmission device includes a first wavelength multiplexer, a second wavelength multiplexer, a wavelength converter and a third wavelength multiplexer. The first wavelength multiplexer multiplexes optical signals in a first wavelength band to generate first wavelength multiplexed light. The second wavelength multiplexer multiplexes optical signals in the first wavelength band to generate second wavelength multiplexed light in a first polarization. The wavelength converter converts a wavelength of the second wavelength multiplexed light from the first wavelength band into a second wavelength band by a cross phase modulation among the second wavelength multiplexed light, first pump light in a second polarization and second pump light in the second polarization. The second polarization is orthogonal to the first polarization. The third wavelength multiplexer multiplexes the second wavelength multiplexed light whose wavelength has been converted by the wavelength converter and the first wavelength multiplexed light.

Wavelength converter and optical transmission device that includes wavelength converter

An optical transmitter includes: a modulator, square law detector, and a processor. The modulator generates an optical signal indicating transmission data. The square law detector detects an intensity of the optical signal using a photodetector and output first intensity data indicating the detected intensity. The processor calculates, based on the transmission data, an electric field of the optical signal generated by the modulator by using parameters pertaining to a state of the modulator. The processor calculates second intensity data indicating the intensity of the optical signal based on the calculated electric field. The processor updates the parameters so as to reduce a difference between the first intensity data and the second intensity data. The processor controls the state of the modulator based on the parameters.

Optical transmitter and control method for optical transmitter

A transmission device including a demultiplexer configured to demultiplex a multiplexed light obtained by multiplexing the plurality of wavelength division multiplexing (WDM) optical signals including different wavelength bands into the plurality of WDM optical signals, a plurality of optical amplifiers configured to amplify the plurality of WDM optical signals, respectively, a wavelength converter configured to convert a first wavelength band of the wavelength bands of at least a first WDM optical signal of the plurality of WDM optical signals amplified by the plurality of optical amplifiers into a second wavelength band of the wavelength bands of a second WDM optical signal of the plurality of WDM optical signals so that the second wavelength band does not overlap among the wavelength bands, and a multiplexer configured to multiplex the plurality of WDM optical signals which include the wavelength bands converted by the wavelength converter.

Transmission device, transmission method, and transmission system

An optical system, comprising a first wavelength conversion module to: adjust a power of a first pump wavelength; couple an input signal with the first pump wavelength to generate a first coupled signal; perform a first wavelength conversion of the first coupled signal to generate a first wavelength converted signal, the power of the first pump wavelength is adjusted such that the first wavelength conversion is performed with 0 dB conversion efficiency; the optical amplifier to amplify the first wavelength converted signal; a second wavelength conversion module to: adjust a power of a second pump wavelength; couple the amplified first wavelength converted signal with the second pump wavelength to generate a second coupled signal; perform a second wavelength conversion of the second coupled signal to generate a second wavelength converted signal with 0 dB conversion efficiency.

Optical amplification in an optical network

A device includes a first excitation light source that emits first excitation light, a second excitation light source that emits second excitation light, a wavelength converter that converts signal light of a first wavelength into signal light of a second wavelength according to the first excitation light, and a measurer that measures a frequency difference between the first excitation light and the second excitation light, wherein when an abnormality of the first excitation light is detected, the second excitation light source is adjusted so that a frequency of the second excitation light is aligned with a frequency of the first excitation light before the abnormality detection, based on the frequency difference before the abnormality detection, and the wavelength converter converts the signal light of the first wavelength into the signal light of the second wavelength according to the second excitation light, after adjusting the frequency of the second excitation light.

Wavelength conversion device and excitation light switching method

A communication device used in an optical communication system, the communication device includes a mode change over device configured to switch between a learning mode for learning a normal state of an optical transmission path before operation and a monitoring mode for monitoring a state of the optical transmission path during operation, an anomaly detector configured to detect an anomaly of the optical transmission path using a prediction model determined by the learning mode when the monitoring mode is selected, and a data writer configured to extract waveform data including information related to the anomaly to output the extracted waveform data to an outside when the anomaly is detected.

Communication device and communication method

An optical transmission device includes: a frontend circuit, a converter, an equalizer, a recovery, spectrum detector a correction information generator, and a transmitter. The frontend circuit converts an optical signal received via an optical network into an electric signal. The converter converts an output signal of the frontend circuit into a digital signal. The equalizer equalizes the digital signal or a second digital signal that is generated based on the digital signal. The recovery recovers a symbol from an output signal of the equalizer. The spectrum detector detects a reception spectrum of the optical signal based on the digital signal or the second digital signal. The correction information generator generates, according to the reception spectrum, correction information for correcting a shape of a transmission spectrum of the optical signal. The transmitter transmits the correction information to the source device.

Optical transmission device and optical transmission system

A method includes multiplexing signal light of first polarization and excitation light, and multiplexing signal light of second polarization, which is perpendicular to the first polarization, and the excitation light, modulating the signal light of the first polarization before the wavelength conversion, and reducing a modulation component in signal light after wavelength conversion, modulating the signal light of the second polarization before the wavelength conversion, and reducing the modulation component in the signal light after the wavelength conversion, and multiplexing the signal light of the first polarization after the wavelength conversion and the signal light of the second polarization after the wavelength conversion.

Wavelength conversion device and method of performing wavelength conversion

An optical network device receives an optical signal, to which polarization information is added, from a transmitter via a transmission line. The receiver generates electric-field-information signal of the optical signal. The processor acquires, for respective polarization rotation amounts, the electric-field-information signal during a period specified by the polarization information. The processor calculates, for respective polarization rotation amounts and based on the electric-field-information signal, evaluation values corresponding to powers of the optical signal at a plurality of positions on the transmission line. The processor calculates, for respective positions, variations in the evaluation values corresponding to the polarization rotation amounts. The processor output information that indicates a first position when the variation in the evaluation values for the first position is larger than that for a second position where the second position is adjacent to the first position on a transmitter side.

Optical network device and method for monitoring transmission line

A wavelength converter includes an excitation light source outputting excitation light, a beam splitter receiving an input of the excitation light and an input of the optical signal and to divide both the inputted excitation light and the inputted optical signal into a first polarization component and a second polarization component, a non-linear optical fiber as a non-polarization-maintaining fiber, an accommodation section securing and accommodating the non-linear optical fiber, a first collimator lens disposed between the beam splitter and a first end of the non-linear optical fiber, and a second collimator lens disposed between the beam splitter and a second end of the non-linear optical fiber, wherein the optical signal is inputted to the beam splitter from a direction different from the input of the excitation light.

Wavelength converter and transmission apparatus

A wavelength converter includes a first phase modulator configured to perform phase modulation on pump light in accordance with a first phase modulation signal, a second phase modulator configured to perform phase modulation on signal light in accordance with a second phase modulation signal, a wavelength converter configured to multiplex the signal light having undergone the phase modulation with the pump light having undergone the phase modulation, the wavelength converter configured to perform wavelength conversion on the signal light in accordance with the pump light, a detector configured to detect a modulation component from the signal light having undergone the phase modulation and the pump light having undergone the phase modulation, and a generator configured to generate the first phase modulation signal and the second phase modulation signal so as to minimize the detected modulation component.

Wavelength converter apparatus and method of performing wavelength conversion

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Kawasaki, Japan

Takeshi Hoshida