公开(公告)号：US20220140906A1

公开(公告)日：2022-05-05

申请号：US17426817

申请日：2020-01-30

Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATION

Inventor： Takashi MITSUI ,  Toshiaki SHITABA ,  Akihiro TANABE ,  Kengo HORIKOSHI ,  Hisao YOSHINAGA

IPC: H04B10/293 ,  H04B10/572

Abstract: An optical transmission system includes: a first optical transmitting unit for transmitting a first optical signal having a first wavelength; a second optical transmitting unit for transmitting a second optical signal having a second wavelength; an output adjustment unit for acquiring the first optical signal and the second optical signal, adjusting signal intensities of the acquired optical signals, and outputting the optical signals; a multiplexer for multiplexing the first optical signal and the second optical signal that have been subjected to signal intensity adjustment and outputting a multiplexed signal; an amplifier for amplifying the multiplexed signal; a first optical receiving unit for receiving the amplified first optical signal; and a second optical receiving unit for receiving the amplified second optical signal. The output adjustment unit adjusts the signal intensities of the first optical signal and the second optical signal such that the signal intensity of the first optical signal received by the first optical receiving unit is larger than or equal to a first predetermined value, and the signal intensity of the second optical signal received by the second optical receiving unit is larger than or equal to a second predetermined value.

公开(公告)号：US20230275658A1

公开(公告)日：2023-08-31

申请号：US18016367

申请日：2020-07-30

Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATION

Inventor： Toshiaki SHITABA ,  Tomoaki YOSHIDA ,  Akihiro TANABE ,  Takashi MITSUI

IPC: H04B10/077 ,  H04B10/61

CPC classification number: H04B10/077 ,  H04B10/614

Abstract: In an optical transmission system including a plurality of optical transmitting units and a relay device, the plurality of optical transmitting units include a frequency modulation conversion unit that converts an input signal into a frequency modulation signal through frequency modulation conversion processing, a multiplexing unit that multiplexes monitoring signals with different frequencies with the frequency modulation signal, and an optical modulation unit that converts the frequency modulation signal that is an electric signal in which the monitoring signals are multiplexed into optical signals having different wavelengths, and the relay device includes a photoelectric conversion unit that acquires a combined signal obtained by combining optical signals having different wavelengths from each other and converts the combined signal into an electric signal, and a measuring unit that measures transmission quality of the plurality of monitoring signals included in the electric signal.

公开(公告)号：US20230254060A1

公开(公告)日：2023-08-10

申请号：US18012076

申请日：2020-07-02

Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATION

Inventor： Akihiro TANABE ,  Toshiaki SHITABA ,  Takashi MITSUI ,  Tomoaki YOSHIDA

IPC: H04J14/02

CPC classification number: H04J14/0298

Abstract: An apparatus includes a reception processing unit configured to output a frequency division multiplexed signal obtained from a transmission signal transmitted over the wired communication network, an output control unit configured to output, in a case that apparatus identifying data matches signal specifying data, a frequency band specifying data indicating a frequency band corresponding to the signal specifying data, the apparatus identifying data being for requesting signal quality degradation, and the signal specifying data specifying a carrier signal requesting signal quality degradation among a plurality of carrier signals included in the frequency division multiplexed signal, a disturbing signal generation unit configured to generate a disturbing signal in a frequency band corresponding to the frequency band specifying data output by the output control unit, and a multiplexing unit configured to multiplex the frequency division multiplexed signal and the disturbing signal to output.

公开(公告)号：US20210168475A1

公开(公告)日：2021-06-03

申请号：US15734192

申请日：2019-06-06

Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATION

Inventor： Keita NISHIMOTO ,  Takashi MITSUI ,  Tomoya HATANO

IPC: H04Q11/00 ,  H04L12/26 ,  H04L12/911 ,  H04B10/272 ,  H04L12/44

Abstract: An optical line terminal is provided with: an absorption unit that acquires first information of a type and a format that are dependent on a communication scheme and that converts the acquired first information into second information of a type and a format that are common to mutually different communication schemes; and a bandwidth allocation unit that determines bandwidth allocation of an upstream signal allocated to an optical network unit on the basis of the second information.

公开(公告)号：US20230353249A1

公开(公告)日：2023-11-02

申请号：US18019280

申请日：2020-09-01

Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATION

Inventor： Toshiaki SHITABA ,  Tomoaki YOSHIDA ,  Akihiro TANABE ,  Takashi MITSUI

IPC: H04B10/516 ,  H04B10/50

CPC classification number: H04B10/516 ,  H04B10/503

Abstract: An optical transmission device includes a distribution unit which generates a first modulated signal and a second modulated signal by distribution processing for an input signal; a first phase modulator which generates a first optical signal phase-modulated in accordance with the first modulated signal by using a laser beam based on a first oscillation frequency; a phase adjustment unit which generates the second modulated signal of a phase opposite to a phase of the first modulated signal; a second phase modulator which generates a second optical signal phase-modulated in accordance with the second modulated signal of the opposite phase by using a laser beam based on a second oscillation frequency; a multiplexing unit which multiplexes the first optical signal and the second optical signal; and a detection unit which generates a frequency-modulated signal by performing square-law detection processing on a result of multiplexing.

公开(公告)号：US20210168022A1

公开(公告)日：2021-06-03

申请号：US17258589

申请日：2019-06-25

Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATION

Inventor： Takamitsu TOCHINO ,  Takashi MITSUI ,  Tomoya HATANO

IPC: H04L12/24 ,  H04J14/08 ,  H04L12/801

Abstract: A first communication device in an optical access system in which the first communication device and a plurality of second communication devices communicate through a time division multiple access scheme includes: an Ethernet (registered trademark) controller configured to implement a communication as an Ethernet communication; a link failure detection unit configured to detect, when the plurality of second communication devices perform an initial connection to a network in the optical access system, whether a link failure has occurred based on collision detection of an optical signal transmitted by each of the plurality of second communication devices; and a signal processing unit configured to output, when the link failure detection unit detects that the link failure has not occurred, an initial connection start notification for causing initiation of a processing of the initial connection.

公开(公告)号：US20210051382A1

公开(公告)日：2021-02-18

申请号：US16976357

申请日：2019-02-21

Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATION

Inventor： Takamitsu TOCHINO ,  Takashi MITSUI ,  Kota ASAKA ,  Tomoya HATANO

IPC: H04Q11/00

Abstract: Transmitting devices used in an optical access system in which a plurality of the transmitting devices transmit an optical burst signal to a receiving device by time division multiple access, the transmitting devices each including an arithmetic processing unit, the arithmetic processing unit including: a data signal transmission instruction unit, the a data signal transmission instruction unit that outputs a first instruction for controlling transmission processing of a data signal on the basis of a requester's instruction; an optical signal control instruction unit that outputs a second instruction for controlling output processing of an optical signal on the basis of the requester's instruction; and an instruction output adjustment unit that adjusts a timing at which the first instruction is output and a timing at which the second instruction is output.

公开(公告)号：US20230135622A1

公开(公告)日：2023-05-04

申请号：US17910919

申请日：2020-03-13

Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATION

Inventor： Akihiro TANABE ,  Takashi MITSUI ,  Toshiaki SHITABA ,  Tomoaki YOSHIDA

IPC: H04B10/032 ,  H04B10/61

Abstract: An optical transmission apparatus includes an input unit, a demultiplexing unit, a measurement unit, and a switching unit. The input unit inputs a first multiplexed signal and a second multiplexed signal each obtained by multiplexing a plurality of optical signals having different wavelengths. The demultiplexing unit demultiplexes the first multiplexed signal and the second multiplexed signal by wavelength. The measurement unit measures qualities of a plurality of optical signals obtained by demultiplexing the first multiplexed signal and qualities of a plurality of optical signals obtained by demultiplexing the second multiplexed signal. The switching unit performs switching between the first multiplexed signal and the second multiplexed signal to be output to a subsequent stage based on a result of measurement by the measurement unit.

公开(公告)号：US20230099159A1

公开(公告)日：2023-03-30

申请号：US17911027

申请日：2020-03-13

Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATION

Inventor： Akihiro TANABE ,  Takashi MITSUI ,  Tomoaki YOSHIDA ,  Toshiaki SHITABA

IPC: H04B10/61 ,  H04B10/572 ,  H04B10/294

Abstract: An optical transmission apparatus of an embodiment is an apparatus for redundantly transmitting a multiplexed signal obtained by multiplexing N (N is an integer of 2 or greater) optical signals having different wavelengths, the apparatus including: a first demultiplexing unit to which a first multiplexed signal is input, the first demultiplexing unit configured to demultiplex the input first multiplexed signal into the N optical signals; N first detection units to which the N optical signals demultiplexed by the first demultiplexing unit are respectively input, each of the N first detection units configured to detect presence or absence of deterioration of a corresponding input optical signals of the input optical signals based on a signal level of the corresponding input optical signal; a second demultiplexing unit to which a second multiplexed signal is input, the second demultiplexing unit configured to demultiplex the input second multiplexed signal into the N optical signals; N second detection units to which the N optical signals demultiplexed by the second demultiplexing unit are respectively input, each of the N second detection units configured to detect presence or absence of deterioration of a corresponding input optical signal of the input optical signals based on a signal level of the corresponding input optical signal; and a selection unit configured to select, based on the detection result of presence or absence of deterioration of each of the optical signals by the first detection units and the second detection units, N optical signals having different wavelengths from either the optical signals demultiplexed by the first demultiplexing unit or the optical signals demultiplexed by the second demultiplexing unit.

公开(公告)号：US20220131633A1

公开(公告)日：2022-04-28

申请号：US17426800

申请日：2020-01-31

Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATION

Inventor： Takashi MITSUI ,  Toshiaki SHITABA

IPC: H04J14/02

Abstract: An optical transmission system includes: first and second optical transmitting units for respectively transmitting first and second optical signals that are obtained, respectively, as a result of first and second frequency-multiplexed multi-channel signals being converted by means of FM batch conversion; a carrier monitoring function unit for monitoring each carrier signal included in the optical signals; an output adjustment unit for adjusting signal intensities of the optical signals and outputting the optical signals; a multiplexer for outputting a multiplexed signal of the optical signals; an amplifier for amplifying the multiplexed signal; and first and second optical receiving units for receiving the respective optical signals included in the amplified multiplexed signal. The output adjustment unit adjusts the respective signal intensities of the optical signals such that the signal intensity at each optical receiving unit is larger than or equal to a predetermined value. The carrier monitoring function unit updates the predetermined values based on a minimum optical sensitivity that is calculated based on the amount of frequency deviation of each carrier signal included in the optical signals.