公开(公告)号：US10361779B2

公开(公告)日：2019-07-23

申请号：US15559150

申请日：2016-03-17

Applicant: NEC Corporation

Inventor： Manabu Arikawa ,  Emmanuel Le Taillandier De Gabory ,  Toshiharu Ito

IPC: H04B10/079 ,  H04B10/077 ,  H04B10/2513 ,  H04B10/25 ,  H04B10/2581

Abstract: In the optical transmission system to transmit optical signals using a plurality of adjacent paths, it is difficult to detect a delay difference between a plurality of paths and chromatic dispersion with a high degree of accuracy due to a crosstalk; therefore, a method for detecting optical signal information according to an exemplary aspect of the present invention includes generating a plurality of data signal sequences corresponding to a plurality of paths multiplexed spatially, each of the plurality of data signal sequences obtained by inserting periodically a training signal with a plurality of frequency components in a data signal, in the plurality of data signal sequences, the training signals respectively included in the data signal sequences to be propagated through adjacent paths at least having different frequency components from each other at the same timing, each of a plurality of the training signals included in one of the data signal sequences having the plurality of frequency components whose frequency difference differing depending on a position to be inserted; and calculating a propagation delay difference between the plurality of paths and chromatic dispersion amounts in the plurality of paths from the plurality of frequency components included in the training signals having been propagated through the plurality of paths by optical signals.

公开(公告)号：US09729229B2

公开(公告)日：2017-08-08

申请号：US14782831

申请日：2013-04-09

Applicant: NEC Corporation

Inventor： Emmanuel Le Taillandier De Gabory ,  Toshiharu Ito ,  Manabu Arikawa

IPC: H04B10/61 ,  H04J14/00 ,  H04B10/077 ,  H04J14/04 ,  H04L25/14 ,  H04B10/2581

CPC classification number: H04B10/0775 ,  H04B10/2581 ,  H04B10/611 ,  H04B10/615 ,  H04B10/6163 ,  H04B10/6164 ,  H04B10/6165 ,  H04J14/00 ,  H04J14/04 ,  H04L25/14

Abstract: The reception (102) reception unit includes; a first processing unit processing a first signal received from a source channel, and including a filtering unit to filter said first signal in digital domain, and extract unit to extract a information from said first signal; a second processing unit processing a second signal received from a destination channel, and said source channel and said destination channel are distinct each other; a third processing unit providing said information extracted from said first signal to said second signal said third processing unit executes; providing said information from said first processing unit to said second processing unit using information lanes of a clock rate strictly lower than a symbol rate of said second signal, a monitoring unit to generate a monitor signal according to the quality of said second signal; and a control unit controlling a skew between said first signal and said second signal in a bandwidth of said filtering units in said first processing unit.

公开(公告)号：US20150078744A1

公开(公告)日：2015-03-19

申请号：US14390471

申请日：2013-04-16

Applicant: NEC Corporation

Inventor： Toshiharu Ito ,  Manabu Arikawa ,  Emmanuel Le Taillandier De Gabory

IPC: H04B10/25

CPC classification number: H04B10/2503 ,  G02B6/02042 ,  G02B6/4246 ,  H04B10/2581 ,  H04J14/04

Abstract: It is difficult in an optical transmission system using a multicore optical fiber to provide high-capacity transmission in which good signal quality is obtained, therefore, a multiplexed optical transmission line according to an exemplary aspect of the present invention includes at least one first optical transmission line propagating first signal light in a first direction; and at least one second optical transmission line propagating second signal light in a second direction opposite to the first direction, wherein the second optical transmission line is disposed in at least one of positions adjacent to the first optical transmission line wherever the first optical transmission line may be disposed.

Abstract translation: 在使用多芯光纤的光传输系统中难以提供其中获得良好的信号质量的高容量传输是困难的，因此，根据本发明的示例性方面的复用光传输线包括至少一个第一光传输 沿第一方向线传播第一信号光; 并且至少一个第二光传输线在与第一方向相反的第二方向上传播第二信号光，其中第二光传输线设置在与第一光传输线相邻的位置中的至少一个位置， 被处置

公开(公告)号：US11637636B2

公开(公告)日：2023-04-25

申请号：US17613149

申请日：2020-05-13

Applicant: NEC Corporation

Inventor： Manabu Arikawa ,  Toshiharu Ito

IPC: H04B10/06 ,  H04B10/61 ,  H04B10/118

Abstract: A receiving optical system control device according to the present invention has: a light intensity calculation means for calculating, from a reception signal acquired by receiving, for each of plurality of mode light beams which are of the incident optical beams and which have been coupled to a plurality of propagation modes of the optical transmission medium by an optical system provided with a variable mechanism, the light intensity of each of the mode light beams; an optical phase calculation means for calculating the optical phase of each of the mode light beams from the reception signal; a relative phase calculation means for calculating the relative phase between the plurality of mode light beams from the optical phases; and a control amount calculation means for calculating the control amount of the variable mechanism from the light intensity and the relative phase.

公开(公告)号：US11206081B2

公开(公告)日：2021-12-21

申请号：US17044213

申请日：2019-03-22

Applicant: NEC Corporation

Inventor： Manabu Arikawa ,  Toshiharu Ito

IPC: H04B10/11 ,  H04J14/06

Abstract: An optical reception terminal includes a plurality of matrix filters (40, 41) respectively provided for a plurality of modes and configured to perform polarization separation and equalization on a coherently received signal in a corresponding mode, and two combining filters (50, 51) respectively provided for two polarizations and configured to combine signals in corresponding polarization among signals output from the plurality of matrix filters (40, 41) after weighting the signals. Filter coefficients of the plurality of matrix filters (40, 41) and weighting coefficients of the two combining filters (50, 51) are controlled based on a deviation from a desired state of both signals in two polarizations after combining by the two combining filters (50, 51), so as to minimize a sum of deviations.

公开(公告)号：US10998973B2

公开(公告)日：2021-05-04

申请号：US16605321

申请日：2018-04-18

Applicant: NEC Corporation

Inventor： Manabu Arikawa ,  Toshiharu Ito

IPC: H04B10/118 ,  H04B10/61 ,  H04B17/336

Abstract: The signal combining device includes: a plurality of first filters to subject each of a plurality of reception signals to processing with first filter coefficients, the plurality of reception signals being generated by subjecting optical signals to coherent detection; a plurality of second filters to subject outputs of the first filters to processing with second filter coefficients; a combiner to output combined signals acquired by combining outputs of the second filters; and a controller to perform adaptive control for each of the first filter coefficients and each of the second filter coefficients with different step sizes in each other, so that the combined signals are in a predetermined state, based on the reception signals input to the first filters and the combined signals, and to switch an update state of a filter coefficient of each of the first filters, based on magnitudes of the second filter coefficients.

公开(公告)号：US10862593B2

公开(公告)日：2020-12-08

申请号：US16088328

申请日：2017-03-17

Applicant: NEC Corporation

Inventor： Kohei Hosokawa ,  Toshiharu Ito ,  Seigo Takahashi ,  Manabu Arikawa ,  Takashi Ishikawa ,  Yoshimasa Ono

IPC: H04B10/69 ,  H04J14/04 ,  H04B17/336 ,  H04B10/11

Abstract: The objective of the present invention is to reduce the size of a receiving device circuit in an optical space communication system while maintaining communication stability. A data receiving device which decodes one item of data from a plurality of input signals includes: two or more digital signal processing means for subjecting the plurality of input signals to signal processing; a first recording means for temporarily recording the plurality of input signals; a SN ratio estimating means for estimating S/N ratios of each of the plurality of input signals and determining the number of the plurality of input signals to be combined, and the signals to be combined; and a scheduling means for carrying out overall control on the basis of the results from the SN ratio estimating means.

公开(公告)号：US10432318B2

公开(公告)日：2019-10-01

申请号：US16066854

申请日：2017-01-10

Applicant: NEC CORPORATION

Inventor： Manabu Arikawa ,  Toshiharu Ito

IPC: H04B10/06 ,  H04B10/61 ,  H04B10/112 ,  H04B10/118 ,  H04L27/22 ,  H04L27/06

Abstract: In order to increase a compensation range for Doppler shift compensation, this digital signal processing circuit is provided with a Doppler shift compensation unit which, on the basis of a sample sequence signal which is oversampled at N (where N is an integer at least equal to 2) times a symbol rate and includes a central sample corresponding to the timing at a symbol center, and a transition sample corresponding to the timing of a symbol transition, finds a Doppler shift amount included in the sample sequence signal and performs Doppler shift compensation. The Doppler shift compensation unit includes a symbol determining unit which performs a symbol determination with respect to the central sample and a determination with respect to the transition sample. The Doppler shift compensation unit switches between these determinations for each corresponding sample and performs said determinations in order to obtain a phase difference and thereby detect the Doppler shift amount.

公开(公告)号：US10411802B2

公开(公告)日：2019-09-10

申请号：US15745254

申请日：2016-07-15

Applicant: NEC CORPORATION

Inventor： Akihiro Tanaka ,  Toshiharu Ito ,  Kohei Hosokawa ,  Seigo Takahashi ,  Manabu Arikawa

IPC: H04B10/00 ,  H04B10/40 ,  H04B10/50 ,  H04B10/60 ,  H04B10/112 ,  H04B10/118

Abstract: A receiving-side splitter 4 that constitutes part of an optical communication device 1 splits a receiving-side signal light into a plurality of lights at a splitting ratio according to the intensity distribution of mutually different propagation modes included in the receiving-side signal light passed through a transmission medium 3. A transmission-side splitter 10 splits a transmission-side signal light into a plurality of-lights. A signal processing device 5 detects the light intensity and/or the phase of the receiving-side signal light, and sets a control target value for the light intensity and/or the phase of the transmission-side signal light to a value according to the result of the detection. A modulator 9 adjusts the light intensity or the phase of a the transmission-side signal light so that the light intensity or phase equals the set value. A multiplexer 8 multiplexes the plurality of transmission-side signal lights.