Patents by Inventor Tatsuya Toyozumi
Tatsuya Toyozumi has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).
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Patent number: 9755777Abstract: An optical transmitter includes a dummy optical source, a polarized wave beam coupler, and an auto gain control (AGC)-system amplifier. The dummy optical source outputs, out of an optical signal in which an optical path signal and an optical packet signal are mixed, a dummy signal having a wavelength identical to that of the optical packet signal. The polarized wave beam coupler multiplexes the dummy signal with the optical signal so that the dummy signal is orthogonal to the optical signal so as to output an output signal. The AGC-system amplifier inputs the output signal, and amplifies the output signal with a predetermined amplification factor corresponding to a power difference between input power and output power of an optical amplifier.Type: GrantFiled: June 24, 2015Date of Patent: September 5, 2017Assignee: FUJITSU LIMITEDInventors: Koji Bato, Tomoyuki Sakata, Tatsuro Kishida, Koji Matsunaga, Tatsuya Toyozumi, Yuichiro Sakane, Wataru Kawasaki
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Patent number: 9537599Abstract: An optical transmitter includes an amplifying unit, a monitor, an identifying unit, and a controlling unit. The amplifying unit amplifies an optical signal in which an optical packet signal is mixed in optical path signals. The monitor monitors power of the optical signal on an input stage and an output stage of the optical amplifying unit, respectively. The identifying unit identifies an optical packet signal section on the input stage side based on the monitoring result on the input stage side, and identifies an optical packet signal section on the output stage side based on the monitoring result on the output stage side. The controlling unit compares the power of the identified section on the input stage side with the power of the identified section on the output stage side, and controls an amplification factor of the amplifying unit based on a power difference resulting from the comparison.Type: GrantFiled: June 23, 2015Date of Patent: January 3, 2017Assignee: FUJITSU LIMITEDInventors: Koji Bato, Tomoyuki Sakata, Tatsuro Kishida, Koji Matsunaga, Tatsuya Toyozumi, Yuichiro Sakane, Tomonori Yamada
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Patent number: 9450698Abstract: The optical transmission device includes an N×N optical switch, an optical packet receiver and an optical packet generation unit. The N×N optical switch transmits data in which a plurality of optical signals each having a different wavelength is multiplexed. The optical packet receiver detects change in the number of wavelengths of optical signals constituting the data. The optical packet generation unit generates, when the change is detected by the optical packet receiver, data to be transmitted by the N×N optical switch, using optical signals for the number of wavelengths after the change.Type: GrantFiled: June 3, 2014Date of Patent: September 20, 2016Assignee: FUJITSU LIMITEDInventors: Koji Matsunaga, Tatsuya Toyozumi, Yasuo Tanaka, Yuichiro Sakane, Koji Bato, Wataru Kawasaki, Tatsuhiko Saito
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Patent number: 9270382Abstract: An optical communication apparatus includes a variable resistor unit, a measurement unit, and a control unit. The variable resistor unit is arranged at a pre-stage of an electrical/optical conversion unit, which converts an electrical signal obtained by converting an input packet to an optical signal having a waveform corresponding to a potential difference between a positive phase component and a negative phase component of the electrical signal by using the potential difference. The variable resistor unit provides a resistor that varies a midpoint of potential of the positive phase component or the negative phase component. The measurement unit measures a ratio of a presence period, which is a period where the input packet is present, to a sum of the presence period and a non-presence period. The control unit controls a value of the resistor provided to the positive phase component or the negative phase component based on the ratio.Type: GrantFiled: June 3, 2014Date of Patent: February 23, 2016Assignee: FUJITSU LIMITEDInventors: Yuichiro Sakane, Koji Matsunaga, Yasuo Tanaka, Tatsuya Toyozumi, Koji Bato, Wataru Kawasaki, Tatsuhiko Saito
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Publication number: 20160020866Abstract: An optical transmitter includes a dummy optical source, a polarized wave beam coupler, and an auto gain control (AGC)-system amplifier. The dummy optical source outputs, out of an optical signal in which an optical path signal and an optical packet signal are mixed, a dummy signal having a wavelength identical to that of the optical packet signal. The polarized wave beam coupler multiplexes the dummy signal with the optical signal so that the dummy signal is orthogonal to the optical signal so as to output an output signal. The AGC-system amplifier inputs the output signal, and amplifies the output signal with a predetermined amplification factor corresponding to a power difference between input power and output power of an optical amplifier.Type: ApplicationFiled: June 24, 2015Publication date: January 21, 2016Applicants: FUJITSU LIMITED, FUJITSU TELECOM NETWORKS LIMITEDInventors: Koji BATO, TOMOYUKI SAKATA, Tatsuro Kishida, Koji Matsunaga, Tatsuya Toyozumi, Yuichiro Sakane, Wataru Kawasaki
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Publication number: 20160020852Abstract: An optical transmitter includes an amplifying unit, a monitor, an identifying unit, and a controlling unit. The amplifying unit amplifies an optical signal in which an optical packet signal is mixed in optical path signals. The monitor monitors power of the optical signal on an input stage and an output stage of the optical amplifying unit, respectively. The identifying unit identifies an optical packet signal section on the input stage side based on the monitoring result on the input stage side, and identifies an optical packet signal section on the output stage side based on the monitoring result on the output stage side. The controlling unit compares the power of the identified section on the input stage side with the power of the identified section on the output stage side, and controls an amplification factor of the amplifying unit based on a power difference resulting from the comparison.Type: ApplicationFiled: June 23, 2015Publication date: January 21, 2016Inventors: Koji BATO, Tomoyuki SAKATA, Tatsuro KISHIDA, Koji MATSUNAGA, Tatsuya TOYOZUMI, Yuichiro SAKANE, Tomonori YAMADA
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Patent number: 9112637Abstract: An optical transmission device that receives a wavelength division multiplexed optical signal obtained by dividing an optical packet signal and performing wavelength multiplexing and that transmits via an optical switch the received wavelength division multiplexed optical signal includes an optical power level measurement unit configured to measure respective optical power levels of respective optical signals of wavelengths included in the wavelength division multiplexed optical signal, and a routing information determinator configured to determine routing information of the wavelength division multiplexed optical signal on the basis of the measured optical power levels.Type: GrantFiled: October 11, 2013Date of Patent: August 18, 2015Assignees: FUJITSU LIMITED, FUJITSU TELECOM NETWORKS LIMITEDInventors: Yuichiro Sakane, Koji Bato, Tatsuya Toyozumi, Koji Matsunaga, Wataru Kawasaki, Tatsuhiko Saito
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Publication number: 20140355976Abstract: The optical transmission device includes an N×N optical switch, an optical packet receiver and an optical packet generation unit. The N×N optical switch transmits data in which a plurality of optical signals each having a different wavelength is multiplexed. The optical packet receiver detects change in the number of wavelengths of optical signals constituting the data. The optical packet generation unit generates, when the change is detected by the optical packet receiver, data to be transmitted by the N×N optical switch, using optical signals for the number of wavelengths after the change.Type: ApplicationFiled: June 3, 2014Publication date: December 4, 2014Applicants: FUJITSU LIMITED, FUJITSU TELECOM NETWORKS LIMITEDInventors: Koji Matsunaga, Tatsuya Toyozumi, Yasuo Tanaka, Yuichiro Sakane, Koji Bato, Wataru Kawasaki, Tatsuhiko Saito
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Publication number: 20140355980Abstract: An optical communication apparatus includes a variable resistor unit, a measurement unit, and a control unit. The variable resistor unit is arranged at a pre-stage of an electrical/optical conversion unit, which converts an electrical signal obtained by converting an input packet to an optical signal having a waveform corresponding to a potential difference between a positive phase component and a negative phase component of the electrical signal by using the potential difference. The variable resistor unit provides a resistor that varies a midpoint of potential of the positive phase component or the negative phase component. The measurement unit measures a ratio of a presence period, which is a period where the input packet is present, to a sum of the presence period and a non-presence period. The control unit controls a value of the resistor provided to the positive phase component or the negative phase component based on the ratio.Type: ApplicationFiled: June 3, 2014Publication date: December 4, 2014Applicants: FUJITSU LIMITED, FUJITSU TELECOM NETWORKS LIMITEDInventors: Yuichiro Sakane, Koji Matsunaga, Yasuo Tanaka, Tatsuya Toyozumi, Koji Bato, Wataru Kawasaki, Tatsuhiko Saito
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Patent number: 8891966Abstract: An optical packet switching device causes branching of an optical packet that is input to an optical switch and detects a synchronization pattern having a predetermined number of bits from the branched optical packet. Then, the optical packet switching device calculates a synchronization point indicating a location of the synchronization pattern with respect to a detection timing and controls, in accordance with the calculated synchronization point, a delay amount of a delay element that delays an optical packet ON signal that is output to the optical switch.Type: GrantFiled: April 17, 2012Date of Patent: November 18, 2014Assignees: Fujitsu Limited, Fujitsu Telecom Networks LimitedInventors: Tatsuya Toyozumi, Koji Matsunaga, Yasuo Tanaka, Hironobu Fukuura, Wataru Kawasaki, Shota Mori
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Publication number: 20140112661Abstract: An optical transmission device that receives a wavelength division multiplexed optical signal obtained by dividing an optical packet signal and performing wavelength multiplexing and that transmits via an optical switch the received wavelength division multiplexed optical signal includes an optical power level measurement unit configured to measure respective optical power levels of respective optical signals of wavelengths included in the wavelength division multiplexed optical signal, and a routing information determinator configured to determine routing information of the wavelength division multiplexed optical signal on the basis of the measured optical power levels.Type: ApplicationFiled: October 11, 2013Publication date: April 24, 2014Applicants: FUJITSU TELECOM NETWORKS LIMITED, FUJITSU LIMITEDInventors: Yuichiro Sakane, Koji BATO, Tatsuya Toyozumi, KOJI MATSUNAGA, WATARU KAWASAKI, TATSUHIKO SAITO
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Patent number: 8672566Abstract: A first node apparatus includes: ports; a storage device; and receiving, updating, and transmitting circuits. The storage device stores: information associating, with first identification information identifying a first frame, information distinguishing a first port having been used as a destination port when the first node apparatus has transmitted the first frame; and information associating, with each node apparatus, state information indicating whether frame transmission from each port is feasible. The receiving circuit receives, from a second node apparatus, a second frame including second identification information. When the second identification information is identical with the first, the updating circuit updates the state information associated with a node apparatus being a destination of the second frame to make the state information indicate frame transmission from the first port is not feasible.Type: GrantFiled: November 3, 2011Date of Patent: March 18, 2014Assignee: Fujitsu LimitedInventors: Tadashige Iwao, Yuji Takahashi, Syunsuke Koga, Yuri Noguchi, Masato Miyake, Tatsuya Toyozumi
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Publication number: 20120315039Abstract: An optical packet switching device causes branching of an optical packet that is input to an optical switch and detects a synchronization pattern having a predetermined number of bits from the branched optical packet. Then, the optical packet switching device calculates a synchronization point indicating a location of the synchronization pattern with respect to a detection timing and controls, in accordance with the calculated synchronization point, a delay amount of a delay element that delays an optical packet ON signal that is output to the optical switch.Type: ApplicationFiled: April 17, 2012Publication date: December 13, 2012Applicants: FUJITSU TELECOM NETWORKS LIMITED, FUJITSU LIMITEDInventors: Tatsuya TOYOZUMI, Koji MATSUNAGA, Yasuo TANAKA, Hironobu FUKUURA, Wataru KAWASAKI, Shota MORI
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Publication number: 20120051252Abstract: A first node apparatus includes: ports; a storage device; and receiving, updating, and transmitting circuits. The storage device stores: information associating, with first identification information identifying a first frame, information distinguishing a first port having been used as a destination port when the first node apparatus has transmitted the first frame; and information associating, with each node apparatus, state information indicating whether frame transmission from each port is feasible. The receiving circuit receives, from a second node apparatus, a second frame including second identification information. When the second identification information is identical with the first, the updating circuit updates the state information associated with a node apparatus being a destination of the second frame to make the state information indicate frame transmission from the first port is not feasible.Type: ApplicationFiled: November 3, 2011Publication date: March 1, 2012Applicant: FUJITSU LIMITEDInventors: Tadashige IWAO, Yuji Takahashi, Syunsuke Koga, Yuri Noguchi, Masato Miyake, Tatsuya Toyozumi
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Patent number: 7529240Abstract: A transmission device capable of configuring a communication network over which MC packets are forwarded in a way that does not use bands with futility is disclosed. The transmission device is so configured to transmit, when receiving a multicast packet from a host, to the other transmission device the multicast packet that is to be discarded by the transmission device having no necessity of forwarding the received multicast packet to the next transmission device.Type: GrantFiled: February 18, 2005Date of Patent: May 5, 2009Assignee: Fujitsu LimitedInventors: Junichi Sawada, Hidetoshi Amari, Shinji Takao, Koji Matsunaga, Tatsuya Toyozumi
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Publication number: 20060107128Abstract: An automatic detection of failure occurrence on a network and selection of QoS table defining a priority for communication among the nodes constituting the network in response to a degeneracy situation of the network caused by the failure upon detection thereof make communications among the nodes by using the selected QoS table.Type: ApplicationFiled: February 10, 2005Publication date: May 18, 2006Applicant: Fujitsu LimitedInventors: Koji Matsunaga, Shinji Takao, Tatsuya Toyozumi, Hidetoshi Amari, Junichi Sawada
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Publication number: 20060087966Abstract: A transmission device capable of configuring a communication network over which MC packets are forwarded in a way that does not use bands with futility is disclosed. The transmission device is so configured to transmit, when receiving a multicast packet from a host, to the other transmission device the multicast packet that is to be discarded by the transmission device having no necessity of forwarding the received multicast packet to the next transmission device.Type: ApplicationFiled: February 18, 2005Publication date: April 27, 2006Applicant: Fujitsu LimitedInventors: Junichi Sawada, Hidetoshi Amari, Shinji Takao, Koji Matsunaga, Tatsuya Toyozumi
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Patent number: 6763038Abstract: In a light transmission equipment which can generate a desired concatenation signal from a maximum concatenation signal standardized in a synchronous transmission mode, a master and a slave circuit for clock change are provided respectively inputting at least two data at a maximum transmission rate based on a concatenation standard of a synchronous transmission mode obtained by dividing a desired transmission rate not prescribed in the concatenation standard to perform a concatenation control to the slave circuit by control information from the master circuit side.Type: GrantFiled: March 28, 2000Date of Patent: July 13, 2004Assignee: Fujitsu LimitedInventors: Nobuhiko Usui, Koji Matsunaga, Masayuki Maehira, Tatsuya Toyozumi, Yumiko Ogata, Masahiro Shioda, Atsuki Taniguchi