公开(公告)号：US20250167893A1

公开(公告)日：2025-05-22

申请号：US18839749

申请日：2022-02-25

Applicant: NEC Corporation

Inventor： Hidemi NOGUCHI

IPC: H04B10/291 ,  H04B10/2525

Abstract: An optical network system includes an optical relay apparatus (20) that forms an optical network and a control apparatus (10) that controls the optical relay apparatus (20), in which the control apparatus (10) includes: a management unit (11) configured to manage wavelength information of an optical signal transmitted and received by the optical relay apparatus (20) in a path of the optical network and transmission line information of an optical transmission line connected to the optical relay apparatus (20); and a compensation control unit (12) configured to determine a wavelength dispersion compensation amount compensated in the optical relay apparatus (20) based on the wavelength information and the transmission line information.

公开(公告)号：US20230026901A1

公开(公告)日：2023-01-26

申请号：US17797843

申请日：2021-02-15

Applicant: NEC Corporation

Inventor： Keiichi MATSUMOTO ,  Hidemi NOGUCHI ,  Emmanuel LE TAILLANDIER DE GABORY

IPC: G01K11/3206 ,  G02B6/02

Abstract: Provided are a monitoring device, a monitoring method, and an optical transmission system which are adapted for an increase in the number of cores of a multi-core optical fiber transmission path and suitable for crosstalk monitoring. The monitoring device monitors a multi-core optical fiber transmission path having a plurality of use cores and at least one or more non-use cores, and comprises: an applying means for applying, at a start point of the multi-core optical fiber transmission path, dithering to signal light propagating in the use cores; a monitoring means for monitoring the power of the non-use cores at an input side of a relay in the multi-core optical fiber transmission path; and a separating means for separating a monitoring result from the monitoring means into power components from the plurality of use cores.

公开(公告)号：US20220385026A1

公开(公告)日：2022-12-01

申请号：US17765505

申请日：2019-10-07

Applicant: NEC Corporation

Inventor： Hitoshi TAKESHITA ,  Keiichi MATSUMOTO ,  Hidemi NOGUCHI

IPC: H01S3/10 ,  H01S3/067 ,  H01S3/13 ,  H04B10/25

Abstract: Light amplification devices using coupled multi-core optical fibers have a figure of merit that temporally varies, which makes it difficult to perform performance evaluation and to build a light transmission system using the same. Accordingly, a light amplification device of the present invention comprises: a band control means that controls the wavelength band of a light carrier to generate a band control light; and a band control light amplification means that has a plurality of light amplification media through which the band control light propagates, wherein the band control light amplification means amplifies the band control light in a coupled state in which the light propagating through the plurality of light amplification media induces a crosstalk and wherein the band control means controls the wavelength band such that the band control light having propagated through the plurality of light amplification media has a reduced coherence.

公开(公告)号：US20220166534A1

公开(公告)日：2022-05-26

申请号：US17440420

申请日：2020-02-04

Applicant: NEC Corporation

Inventor： Hidemi NOGUCHI ,  Junichi ABE ,  Masaki SATO

IPC: H04J14/02 ,  H04B10/2507 ,  H04B10/61 ,  H04B10/50

Abstract: To suppress the deterioration of the characteristics of a MIMO equalizer as well as minimizing an increase in circuit size in spite of the occurrence of signal spectrum narrowing and asymmetric spectrum degradation, a wavelength-division multiplexing optical transmission system (10) according to an embodiment includes a transmitter (1) that generates one channel signal by wavelength-division multiplexing a plurality of subcarrier signals so as to overlap each other and transmits the channel signal, and a receiver (2) that separates a received channel signal into subcarrier signals, and performs equalization using an MIMO equalizer (3) including a FDE-MIMO equalizer (4) and a TDE-MIMO equalizer (5) on each of the separated subcarrier signals.

公开(公告)号：US20210341612A1

公开(公告)日：2021-11-04

申请号：US17041150

申请日：2018-03-28

Applicant: NEC Corporation

Inventor： Akira TSUJI ,  Hidemi NOGUCHI

IPC: G01S17/88 ,  G01S17/42 ,  G01S7/481

Abstract: A monitoring control device (1) according to the present embodiment is, for example, a monitoring control device used in a monitoring system that monitors a monitoring target facility by using a distance measurement sensor (5). The monitoring control device (1) includes: a sensing region acquisition unit (3) configured to acquire measurement data indicating a sensing region of the distance measurement sensor (5) provided in order to monitor a monitoring target facility; and a management unit (4) configured to identify a non-monitoring region of the monitoring target facility, based on the sensing region and position data of the distance measurement sensor (5).

公开(公告)号：US20210018626A1

公开(公告)日：2021-01-21

申请号：US16982021

申请日：2018-03-28

Applicant: NEC Corporation

Inventor： Hidemi NOGUCHI

IPC: G01S17/34

Abstract: A distance measurement device (2000) generates transmission light by modulating an optical carrier wave. The distance measurement device (2000) transmits the generated transmission light, and receives reflected light acquired by the transmission light being reflected by a measured object (10). The distance measurement device (2000) generates a first beat signal by causing the transmission light to interfere with reference light. The distance measurement device (2000) generates a second beat signal by causing the reflected light to interfere with the reference light. The distance measurement device (2000) calculates a distance to the measured object (10), based on a difference between the first beat signal and the second beat signal.

公开(公告)号：US20200014468A1

公开(公告)日：2020-01-09

申请号：US16490632

申请日：2018-03-05

Applicant: NEC Corporation

Inventor： Hidemi NOGUCHI

IPC: H04B10/67 ,  H04B10/61 ,  H04B10/079 ,  H04J14/02

Abstract: The receiving-side system (10) includes a smaller number of optical reception front ends (12) than the number of a plurality of wavelength-multiplexed subcarrier signals. Each of the optical reception front ends (12) is configured to receive two or a plurality subcarrier signals of the plurality of subcarrier signals. A frequency offset monitoring unit (22) monitors frequency offsets of the respective subcarrier signals received by the optical reception front end (12). A light source frequency control unit (24) controls at least one of a light source frequency of the transmitting-side system (2) and a light source frequency of the receiving-side system (10) based on a result of the monitoring performed by the frequency offset monitoring unit (22).

公开(公告)号：US20170338895A1

公开(公告)日：2017-11-23

申请号：US15534120

申请日：2015-12-15

Applicant: NEC Corporation

Inventor： Wakako YASUDA ,  Hidemi NOGUCHI

IPC: H04B10/69 ,  H04L25/03 ,  H04B10/2507

CPC classification number: H04B10/6971 ,  H04B10/2507 ,  H04B10/61 ,  H04B10/6161 ,  H04B10/6162 ,  H04L25/03885

Abstract: It is difficult to obtain a demodulated signal with high signal quality in a digital optical receiver because it is difficult to compensate for each of different types of waveform distortion by a high-performance equalization process; therefore, a digital signal processor according to an exemplary aspect of the present invention includes a fixed equalization means for performing a distortion compensation process based on a fixed equalization coefficient on an input digital signal; an adaptive equalization means for performing an adaptive distortion compensation process based on an adaptive equalization coefficient on an equalized digital signal output by the fixed equalization means; a low-speed signal generation means for generating a low-speed digital signal by intermittently extracting one of the input digital signal and the equalized digital signal; a low-speed equalization coefficient calculation means for calculating a low-speed equalization coefficient to be used for a distortion compensation process of the low-speed digital signal; and a fixed equalization coefficient calculation means for calculating the fixed equalization coefficient by using at least a predetermined coefficient out of the low-speed equalization coefficient and the predetermined coefficient.

公开(公告)号：US20250080226A1

公开(公告)日：2025-03-06

申请号：US18816267

申请日：2024-08-27

Applicant: NEC Corporation

Inventor： Shoma TATENO ,  Hidemi NOGUCHI

IPC: H04B10/291

Abstract: An optical repeater of an optical network system performs chromatic dispersion compensation processing on an electrical signal based on a received optical signal, the processing being based on a carrier frequency and frequency band of the relevant channel among a plurality of channels included in the optical signal; and phase conjugation processing on the electrical signal based on the received optical signal.

公开(公告)号：US20250070877A1

公开(公告)日：2025-02-27

申请号：US18726472

申请日：2022-01-18

Applicant: NEC Corporation

Inventor： Ankith VINAYACHANDRAN ,  Shinsuke FUJISAWA ,  Naoto ISHII ,  Hidemi NOGUCHI ,  Emmanuel LE TAILLANDIER DE GABORY

IPC: H04B10/2507 ,  H04B10/58 ,  H04B10/60

Abstract: A calibration apparatus trains a first machine learning-based model with a first training dataset to determine configuration parameters of an intermediate pre-distortion compensator in an optical communication system that includes a transmitter, a receiver, and an optical communication channel. The transmitter includes a pre-distortion compensator, the intermediate pre-distortion compensator, and an MZM compensator. The calibration apparatus trains a second machine learning-based model with a second training dataset to determine configuration parameters of the post-distortion compensator in the receiver. The calibration apparatus trains a third machine learning-based model with a third training dataset to determine configuration parameters of the pre-distortion compensator. When generating the second training data, the intermediate pre-distortion compensator is configured with the configuration parameters generated using the first machine learning-based model. When generating the third training data, the post-distortion compensator is configured with the configuration parameters generated using the second machine learning-based model.