公开(公告)号：US20160006525A1

公开(公告)日：2016-01-07

申请号：US14837041

申请日：2015-08-27

Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATION

Inventor： Masahiro SUZUKI ,  Takuya OHARA ,  Takashi ONO ,  Shigeki AlSAWA ,  Masahito TOMIZAWA

IPC: H04J3/06 ,  H04J3/16 ,  H04Q11/00 ,  H04J3/07

CPC classification number: H04J3/0658 ,  H04J3/07 ,  H04J3/1652 ,  H04J14/0227 ,  H04Q11/0005 ,  H04Q2011/0045

Abstract: A client signal mapping circuit for accommodating a client signal in a transmission frame, including: a buffer unit configured to temporarily store the client signal; a buffer used amount monitoring unit configured to report a used amount of the buffer unit; a stuff processing determination unit configured to compare the used amount of the buffer unit with a predetermined reference value, and a pseudo random sequence signal and the comparison result; an overhead insertion unit configured to add an overhead to the client signal read from the buffer unit to form a transmission frame; and a reading control unit configured to perform control for reading the client signal from the buffer unit based on determination by the stuff processing determination unit.

公开(公告)号：US20150372766A1

公开(公告)日：2015-12-24

申请号：US14766635

申请日：2014-02-13

Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATION

Inventor： Mitsuteru YOSHIDA ,  Etsushi YAMAZAKI ,  Seiji OKAMOTO ,  Hiroyuki UZAWA ,  Kengo HORIKOSHI ,  Koichi ISHIHARA ,  Takayuki KOBAYASHI ,  Yoshiaki KISAKA ,  Masahito TOMIZAWA ,  Naoki FUJIWARA ,  Tomoyoshi KATAOKA ,  Kazushige YONENAGA

IPC: H04B10/61 ,  H04B10/2507 ,  H04J14/06 ,  H04B10/516

CPC classification number: H04B10/6165 ,  H04B10/2507 ,  H04B10/516 ,  H04B10/61 ,  H04J14/06 ,  H04L27/38 ,  H04L2027/0067 ,  H04L2027/0095

Abstract: An increase in circuit scale is suppressed and a phase variation caused in a transmission path or the like is compensated for. An optical transmission system includes: a pilot symbol detection unit which detects a plurality of pilot symbols intermittently inserted into a received complex electric field signal that is obtained through coherent detection for a received optical signal; an error signal computation unit which calculates a complex electric field error signal indicating a phase variation at each pilot symbol based on the pilot symbols detected by the pilot symbol detection unit and a predetermined reference symbol; a compensation electric field signal generation unit which estimates a phase variation between the pilot symbols in the received complex electric field signal using filter processing based on the complex electric field error signal calculated by the error signal computation unit; and a phase noise compensation unit which performs phase compensation for the received complex electric field signal based on the phase variation between the pilot symbols estimated by the compensation electric field signal generation unit.

Abstract translation: 抑制电路规模的增加，并且补偿在传输路径等中引起的相位变化。 光传输系统包括：导频符号检测单元，其检测间歇地插入到通过接收的光信号的相干检测获得的接收复电场信号中的多个导频符号; 误差信号计算单元，基于由导频符号检测单元检测的导频符号和预定的参考符号，计算指示每个导频符号的相位变化的复电场误差信号; 补偿电场信号生成单元，其基于由所述误差信号计算单元计算的复电场误差信号，使用滤波处理来估计所述接收复电场信号中的导频符号之间的相位变化; 以及相位噪声补偿单元，其基于由补偿电场信号生成单元估计的导频符号之间的相位变化，对接收到的复数电场信号进行相位补偿。

公开(公告)号：US20220321210A1

公开(公告)日：2022-10-06

申请号：US17632589

申请日：2019-08-05

Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATION

Inventor： Kei KITAMURA ,  Fumikazu INUZUKA ,  Kengo SHINTAKU ,  Takuya ODA ,  Takafumi TANAKA ,  Masahito TOMIZAWA

IPC: H04B10/032

Abstract: A transmission apparatus includes a control unit for carrying out processing to secure a resource for a standby system path in response to detection of a sign of failure in an active system path.

公开(公告)号：US20220006577A1

公开(公告)日：2022-01-06

申请号：US17293743

申请日：2019-11-18

Applicant: Nippon Telegraph and Telephone Corporation

Inventor： Kei Kitamura ,  Fumikazu INUZUKA ,  Akira Hirano ,  Masahito TOMIZAWA ,  Takuya OHARA

IPC: H04L1/22 ,  H04L1/00 ,  H04L1/16

Abstract: A transmission apparatus includes redundant first communication devices configured to communicate with a communication apparatus provided in a first network, and redundant second communication devices configured to communicate with a communication apparatus provided in a second network. The second communication devices include respective first ends that are ends of redundant communication paths of the first communication devices, and the first communication devices include respective second ends that are ends of redundant communication paths of the second communication devices.

公开(公告)号：US20180302211A1

公开(公告)日：2018-10-18

申请号：US15568696

申请日：2017-01-16

Applicant: NTT ELECTRONICS CORPORATION ,  NIPPON TELEGRAPH AND TELEPHONE CORPORATION

Inventor： Yasuharu ONUMA ,  Masahiro TACHIBANA ,  Etsushi YAMAZAKI ,  Kazuhito TAKEI ,  Yuki YOSHIDA ,  Masayuki IKEDA ,  Yoshiaki KISAKA ,  Masahito TOMIZAWA

IPC: H04L7/00 ,  H04B1/16 ,  H04L7/033 ,  H03H17/06

CPC classification number: H04L7/0079 ,  H03H17/0027 ,  H03H17/06 ,  H03H17/08 ,  H04B1/16 ,  H04L7/0029 ,  H04L7/005 ,  H04L7/033

Abstract: An FIR filter convolutes sampled data obtained by sampling a reception signal with tap coefficients. A phase difference detector detects a phase difference between a synchronization timing of a signal waveform estimated from an output signal of the FIR filter and a sampling timing of the output signal. A tap coefficient adjuster adjusts the tap coefficients so as to reduce the phase difference detected by the phase difference detector and causes the sampling timing of the output signal of the FIR filter to track the synchronization timing.

公开(公告)号：US20170111116A1

公开(公告)日：2017-04-20

申请号：US15126557

申请日：2014-11-19

Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATION

Inventor： Takuya OHARA ,  Kei KITAMURA ,  Yoshiaki KISAKA ,  Shigeki AISAWA ,  Masahiro SUZUKI ,  Etsushi YAMAZAKI ,  Tomoyoshi KATAOKA ,  Masahito TOMIZAWA ,  Yoshiaki YAMADA ,  Mitsuhiro TESHIMA ,  Akira HIRANO

IPC: H04B10/40 ,  H04B10/60 ,  H04B10/27 ,  H04B10/516

CPC classification number: H04B10/40 ,  H04B10/27 ,  H04B10/5161 ,  H04B10/60 ,  H04J3/00 ,  H04J3/1652 ,  H04J14/00

Abstract: A transport apparatus includes: a client signal transceiving unit which transceives a client signal; a line signal transceiving unit which performs electric-optic conversion on a line signal to be transmitted, transmits an optical line signal, performs optic-electric conversion on a received line signal, and outputs an electrical line signal; and a plurality of signal processing units which perform signal processing on the client signal to generate the line signal to be transmitted and perform signal processing on the electrical line signal to generate the client signal. Each of the plurality of signal processing units includes a signal transceiving unit which performs transfer of a branched signal obtained by branching a signal to be transmitted and a merged signal obtained by merging received signals with another signal processing unit, and the signal transceiving unit of each of the plurality of signal processing units and the signal transceiving unit of the other signal processing unit are coupled via an inter-chip wiring.

公开(公告)号：US20170070296A1

公开(公告)日：2017-03-09

申请号：US15122582

申请日：2015-03-17

Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATION

Inventor： Seiji OKAMOTO ,  Koichi ISHIHARA ,  Etsushi YAMAZAKI ,  Mitsuteru YOSHIDA ,  Tomoyoshi KATAOKA ,  Kazushige YONENAGA ,  Yoshiaki KISAKA ,  Masanori NAKAMURA ,  Masahito TOMIZAWA

IPC: H04B10/516 ,  H04B10/508

CPC classification number: H04B10/516 ,  H04B10/0775 ,  H04B10/2513 ,  H04B10/2557 ,  H04B10/508 ,  H04L27/3455 ,  H04L27/3483 ,  H04L27/366

Abstract: An optical signal transmission apparatus includes a modulation unit which modulates a transmission signal, a training signal sequence generation unit which generates a plurality of signal sequences having power concentrated in a plurality of different frequency bands, at least one of an amplitude and a phase of the plurality of signal sequences being modulated, as a training signal sequence, a signal multiplexing unit which appends the training signal sequence to the transmission signal, and an electro-optical conversion unit which converts a signal sequence obtained by appending the training signal sequence to the transmission signal into an optical signal and transmits the optical signal.

Abstract translation: 光信号传输装置包括：调制单元，其对发送信号进行调制;训练信号序列生成单元，生成具有集中在多个不同频带的功率的多个信号序列，所述训练信号序列生成单元的振幅和相位中的至少一个 多个信号序列作为训练信号序列被调制为将训练信号序列附加到传输信号的信号复用单元，以及电光转换单元，其将通过将训练信号序列附加到传输获得的信号序列 信号转换为光信号并发送光信号。

公开(公告)号：US20220224415A1

公开(公告)日：2022-07-14

申请号：US17614686

申请日：2019-06-06

Applicant: Nippon Telegraph and Telephone Corporation

Inventor： Masanori NAKAMURA ,  Seiji Okamoto ,  Kengo HORIKOSHI ,  Shuto YAMAMOTO ,  Takayuki KOBAYASHI ,  Yoshiaki KISAKA ,  Masahito TOMIZAWA

IPC: H04B10/2513 ,  H04B10/61 ,  H03H17/02

Abstract: An electric digital received signal obtained from a received optical signal is segmented into blocks of a certain length with an overlap of a length determined in advance with an adjacent block. Fourier transformation is performed for each of the blocks. The blocks subjected to the Fourier transformation are stored consecutively in time series, a coefficient determined based on a wavelength dispersion compensation amount according to one of frequency positions and a delay amount according to one of the frequency positions and one of time positions is applied to each of frequency component values included in a plurality of the stored blocks, and the blocks to which the coefficient has been applied and which are obtained by adding up the frequency component values to which the coefficient has been applied for each of the frequency positions are generated. Inverse Fourier transformation is performed on the generated blocks to which the coefficient has been applied. A part of the overlap subjected to the inverse Fourier transformation is removed.

公开(公告)号：US20220006722A1

公开(公告)日：2022-01-06

申请号：US17292577

申请日：2019-11-07

Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATION

Inventor： Kei KITAMURA ,  Fumikazu INUZUKA ,  Akira HIRANO ,  Masahito TOMIZAWA ,  Takuya OHARA

IPC: H04L12/727 ,  H04L12/707 ,  H04L12/703 ,  H04L12/835

Abstract: A transmission apparatus performs communication with a transmission side transmission apparatus via a transmission path of an active system and a transmission path of a standby system. The transmission apparatus includes: a memory configured to have a capacity that is as large as delay caused due to a maximum path difference between the transmission path of the active system and the transmission path of the standby system is allowable; and a memory connection control unit configured to switch connection of the memory and cause a signal of the transmission path of the active system or the transmission path of the standby system to be accumulated in the memory.

公开(公告)号：US20200067598A1

公开(公告)日：2020-02-27

申请号：US16339248

申请日：2017-10-06

Applicant: NTT Electronics Corporation ,  NIPPON TELEGRAPH AND TELEPHONE CORPORATION

Inventor： Mitsuteru YOSHIDA ,  Etsushi YAMAZAKI ,  Yoshiaki KISAKA ,  Masahito TOMIZAWA

IPC: H04B10/2513 ,  H04B10/079 ,  H04L27/26

Abstract: A band division timing adjustment unit (10) aligns timings of a plurality of signals, which are generated by dividing a received signal according to a plurality of frequency bands, in a time domain and combines the plurality of signals for which the timings have been aligned. A chromatic dispersion compensation unit (17) compensates chromatic dispersion of an output signal of the band division timing adjustment unit (10) for each of the plurality of frequency bands.