Patents by Inventor Koji Takeguchi

Koji Takeguchi 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).

  • Publication number: 20100247095
    Abstract: When line trouble occurs in an optical network, the restoration time can be reduced. A transponder 21 includes an active line and a standby line 43, and a transponder 22 includes an active line 42 and a standby line 44. The standby line 44 of the transponder 22 is accommodated in the same optical line as the active line 41 of the transponder 21. Upon detection of line trouble, the receiving transponder 24 acquires a VDC setting value for the active line 41, and sets the VDC setting value for the standby line 44 on the basis of the acquired VDC setting value.
    Type: Application
    Filed: June 14, 2010
    Publication date: September 30, 2010
    Applicant: FUJITSU LIMITED
    Inventors: Takehiro Fujita, Koji Takeguchi, Junji Yamamoto
  • Publication number: 20100165987
    Abstract: There is provided a communication device including a score information storage unit to store score information indicating a score as an evaluated value of a communication path; a receiver unit to receive a route connection notice including current score information; a routing unit to acquire the score information stored in the score information storage unit, and select the communication path next to the communication path based on the acquired score information of the communication path; a score updating unit to add a score of the communication path selected by the routing unit to the current score of the partial communication route indicated by the current score information, and update the current score information to the added score as a new current score; and a transmission unit to transmit the route connection notice including the current score information.
    Type: Application
    Filed: December 17, 2009
    Publication date: July 1, 2010
    Applicant: FUJITSU LIMITED
    Inventors: Koji Takeguchi, Masakazu Bamba, Yasuko Nozu, Katsuhiro Shirai
  • Publication number: 20100118872
    Abstract: A communication apparatus operable to set a path based on path setting information used to set a communication path over a communication network formed by a plurality of the communication apparatuses, the communication apparatus including a first storage medium operable to store first path setting information formatted with a first format, a second storage medium operable to store second path setting information formatted with a second format, and a controller operable to control to convert control information of the communication apparatus in which the first path setting information stored in the first storage medium is set, to the second path setting information formatted with the second format.
    Type: Application
    Filed: October 15, 2009
    Publication date: May 13, 2010
    Applicant: FUJITSU LIMITED
    Inventors: Katsuhiro SHIRAI, Kanji Naito, Koji Takeguchi
  • Patent number: 7548693
    Abstract: A relay transmission apparatus in which the effectiveness of a protecting function is improved by suppressing variation of an OSNR value of a signal regardless of the distance that the signal is transmitted. The relay transmission apparatus is comprised of a first regenerative relay unit, a second regenerative relay unit, and a protection process unit for extracting a signal component from each of the first and second regenerative relay units and selectively outputting either of the extracted signal components as a drop signal.
    Type: Grant
    Filed: July 28, 2004
    Date of Patent: June 16, 2009
    Assignee: Fujitsu Limited
    Inventors: Gaku Kimura, Koji Takeguchi
  • Publication number: 20070248119
    Abstract: In order to increase the efficiency of large-capacity transmission, the continuity of divided signals generated by dividing a multiplexed signal is maintained and the original large-capacity multiplexed signal is restored. A signal dividing section divides a multiplexed signal to generate a plurality of divided signals in the STS or STM transmission interface format. A guarantee information adding section adds guarantee information for guaranteeing the continuity of the divided signals to each of the divided signals to generate transmission signals. A signal sending section sends the transmission signals via a transmission line in the transmission interface format. A signal receiving section receives the transmission signals. A signal restoring section restores the multiplexed signal by constructing the divided signals on the basis of the guarantee information.
    Type: Application
    Filed: May 15, 2007
    Publication date: October 25, 2007
    Inventors: Koji Takeguchi, Ryuichi Moriya, Nobuhiro Rikitake, Hideki Matsui, Hirotaka Morita
  • Patent number: 7283740
    Abstract: An optical network includes a plurality of subnets. The subnets each include a plurality of add/drop nodes coupled to the optical ring and operable to passively add and drop traffic to and from the optical ring. The network further includes a plurality of gateway nodes. The gateway nodes are each coupled to the optical ring at a boundary between neighboring subnets and operable to selectively pass and terminate wavelengths between subnets to allow wavelength reuse in the subnets and to provide protection switching.
    Type: Grant
    Filed: May 29, 2002
    Date of Patent: October 16, 2007
    Assignee: Fujitsu Limited
    Inventors: Susumu Kinoshita, Koji Takeguchi, Ashwin Anil Gumaste
  • Patent number: 7283739
    Abstract: An optical network includes an optical ring and at least three subnets. Each subnet includes a plurality of add/drop nodes coupled to the optical ring. The add/drop nodes are operable to passively add a first traffic stream in a first direction on the optical ring and a second traffic stream in a second direction on the optical ring. The first traffic stream comprises different content than the second traffic stream, and the first traffic stream and the second traffic stream are transmitted on the same wavelength. The network also includes a plurality of gateway nodes. The gateway nodes are each coupled to the optical ring at a boundary between neighboring subnets and are operable to selectively pass and terminate wavelengths between subnets to allow wavelength reuse in the subnets.
    Type: Grant
    Filed: May 29, 2002
    Date of Patent: October 16, 2007
    Assignee: Fujitsu Limited
    Inventors: Susumu Kinoshita, Koji Takeguchi, Ashwin Anil Gumaste
  • Publication number: 20070223371
    Abstract: A flexible open ring optical network includes a plurality of nodes connected by twin or other suitable optical rings. Each node is operable to passively add and passively drop traffic from the rings. The nodes may include a transport element for each ring. The transport elements include an optical splitter element and an optical combiner element. The optical splitter element is operable to passively combine an add signal including local add traffic and a first transport signal including ingress traffic from a coupled optical ring to generate a second transport signal including egress traffic for transmission on the coupled optical ring. The optical combiner element is coupled to the optical splitter element and is operable to passively split a third transport signal including the ingress traffic to generate a drop signal including local drop traffic and a fourth transport signal including the ingress traffic.
    Type: Application
    Filed: May 8, 2007
    Publication date: September 27, 2007
    Applicant: Fujitsu Limited
    Inventors: Susumu Kinoshita, Koji Takeguchi, Satoru Odate, Cechan Tian
  • Publication number: 20070206493
    Abstract: A flexible open ring optical network includes a plurality of nodes connected by twin or other suitable optical rings. Each node is operable to passively add and passively drop traffic from the rings. The nodes may include a transport element for each ring. The transport elements include an optical splitter element and an optical combiner element. The optical splitter element is operable to passively combine an add signal including local add traffic and a first transport signal including ingress traffic from a coupled optical ring to generate a second transport signal including egress traffic for transmission on the coupled optical ring. The optical combiner element is coupled to the optical splitter element and is operable to passively split a third transport signal including the ingress traffic to generate a drop signal including local drop traffic and a fourth transport signal including the ingress traffic.
    Type: Application
    Filed: May 8, 2007
    Publication date: September 6, 2007
    Applicant: Fujitsu Limited
    Inventors: Susumu Kinoshita, Koji Takeguchi, Satoru Odate, Cechan Tian
  • Patent number: 7266294
    Abstract: An optical cross-connect includes multiple input ports that each receives an optical input signal and multiple output ports that each output an optical output signal. The optical cross-connect also includes a distributing amplifier associated with each input port that generates multiple copies of the input signal received at the associated input port and multiple filter units that receive one or more of the copies and forward traffic in selected channels of particular copies. In addition, the optical cross-connect includes a combining amplifier associated with each output port that receives the traffic forwarded by one or more of the filter units and combines the received traffic into an output signal. Moreover, the optical cross-connect includes at least one upgrade input port and at least one upgrade output port expanding the capacity of the optical cross-connect, as well as associated upgrade distributing and combining amplifiers and upgrade filter units.
    Type: Grant
    Filed: December 2, 2003
    Date of Patent: September 4, 2007
    Assignee: Fujitsu Limited
    Inventors: Yasuhiko Aoki, Susumu Kinoshita, Koji Takeguchi
  • Patent number: 7239649
    Abstract: In order to increase the efficiency of large-capacity transmission, the continuity of divided signals generated by dividing a multiplexed signal is maintained and the original large-capacity multiplexed signal is restored. A signal dividing section divides a multiplexed signal to generate a plurality of divided signals in the STS or STM transmission interface format. A guarantee information adding section adds guarantee information for guaranteeing the continuity of the divided signals to each of the divided signals to generate transmission signals. A signal sending section sends the transmission signals via a transmission line in the transmission interface format. A signal receiving section receives the transmission signals. A signal restoring section restores the multiplexed signal by constructing the divided signals on the basis of the guarantee information.
    Type: Grant
    Filed: June 21, 2001
    Date of Patent: July 3, 2007
    Assignee: Fujitsu Limited
    Inventors: Koji Takeguchi, Ryuichi Moriya, Nobuhiro Rikitake, Hideki Matsui, Hirotaka Morita
  • Patent number: 7231148
    Abstract: A flexible open ring optical network includes a plurality of nodes connected by twin or other suitable optical rings. Each node is operable to passively add and passively drop traffic from the rings. The nodes may include a transport element for each ring. The transport elements include an optical splitter element and an optical combiner element. The optical splitter element is operable to passively combine an add signal including local add traffic and a first transport signal including ingress traffic from a coupled optical ring to generate a second transport signal including egress traffic for transmission on the coupled optical ring. The optical combiner element is coupled to the optical splitter element and is operable to passively split a third transport signal including the ingress traffic to generate a drop signal including local drop traffic and a fourth transport signal including the ingress traffic.
    Type: Grant
    Filed: March 28, 2002
    Date of Patent: June 12, 2007
    Assignee: Fujitsu Limited
    Inventors: Susumu Kinoshita, Koji Takeguchi, Satoru Odate, Cechan Tian
  • Patent number: 7200332
    Abstract: A system and method for assigning a traffic channel to a wavelength in a multi-ring optical network having bifurcated work and protect wavelengths includes determining a transport direction for the traffic channel in a ring of the multi-ring optical network. An inter/intra ring type of the traffic channel is determined. The traffic channel is assigned to a wavelength in the ring based on the transport direction and the inter/intra ring type of the traffic channel. In a particular embodiment, the traffic channel may be assigned to one of an odd and even wavelength based on the transport direction and one of a high and low wavelength based on the inter/intra ring type.
    Type: Grant
    Filed: March 15, 2002
    Date of Patent: April 3, 2007
    Assignee: Fujitsu Limited
    Inventors: Ashwin Anil Gumaste, Susumu Kinoshita, Koji Takeguchi
  • Patent number: 7184663
    Abstract: An optical network includes an optical ring and a plurality of add/drop nodes coupled to the optical ring. Each of the add/drop nodes is operable to passively add and drop one or more traffic streams to and from the optical ring, and each traffic stream comprises a channel. A hub node also coupled to the optical ring is operable to selectively pass and terminate individual traffic streams.
    Type: Grant
    Filed: October 1, 2002
    Date of Patent: February 27, 2007
    Assignee: Fujitsu Limited
    Inventors: Susumu Kinoshita, Ashwin Anil Gumaste, Koji Takeguchi
  • Patent number: 7116905
    Abstract: A method and system for control signaling in an open ring optical network includes transmitting traffic in an optical ring. At each of a plurality of nodes along the ring, local traffic is passively added to and passively dropped from the connected ring. At each node, an ingress optical supervisory channel (OSC) signal is dropped from the ring to a managing element. An egress OSC signal is added to the ring from the managing element. The OSC signals may be in-band signal or out-of-band signals.
    Type: Grant
    Filed: March 27, 2002
    Date of Patent: October 3, 2006
    Assignee: Fujitsu Limited
    Inventors: Susumu Kinoshita, Koji Takeguchi, Satoru Odate, Cechan Tian
  • Patent number: 7076163
    Abstract: The method and system for testing during operation of an open ring network includes opening a ring of the network at the node. Traffic circulating on the ring is dropped in the node to a monitoring element prior to or at the opening of the ring in the node. At the monitoring element, a signal received from the ring is tested. During tested and while the ring is open, traffic continues to be communicated between each node on at least one of the ring or a second ring each connecting the nodes of the network.
    Type: Grant
    Filed: March 27, 2002
    Date of Patent: July 11, 2006
    Assignee: Fujitsu Limited
    Inventors: Susumu Kinoshita, Koji Takeguchi, Satoru Odate, Cechan Tian
  • Patent number: 7024121
    Abstract: Proposed is an optical clock distribution system in the WDM network, which particularly relates to a system to control clock synchronization between optical transmission devices constituting an optical communication network. The optical clock distribution system includes an optical clock generator converting a clock signal of PRC (Primary Reference Clock) level into an optical clock signal having a wavelength ?0; a wavelength multiplexer wavelength-multiplexing the optical clock signal having wavelength ?0 together with other optical wavelength data; and a wavelength-demultiplexer provided in a unit of the network, wavelength-demultiplexing the optical clock signal having wavelength ?0, wherein the other optical wavelength data are processed in the unit of the network using the wavelength-demultiplexed optical clock signal having wavelength ?0 as a reference clock.
    Type: Grant
    Filed: October 17, 2002
    Date of Patent: April 4, 2006
    Assignee: Fujitsu Limited
    Inventors: Nobuhiro Rikitake, Hirotaka Morita, Koji Takeguchi, Ryuichi Moriya, Hideki Matsui
  • Publication number: 20050213970
    Abstract: A relay transmission apparatus in which the effectiveness of a protecting function is improved by suppressing variation of an OSNR value of a signal regardless of the distance that the signal is transmitted. The relay transmission apparatus is comprised of a first regenerative relay unit, a second regenerative relay unit, and a protection process unit for extracting a signal component from each of the first and second regenerative relay units and selectively outputting either of the extracted signal components as a drop signal.
    Type: Application
    Filed: July 28, 2004
    Publication date: September 29, 2005
    Inventors: Gaku Kimura, Koji Takeguchi
  • Publication number: 20050175346
    Abstract: In one embodiment, a method is provided for an in-service upgrade of a twin ring optical network comprising a plurality of passive add/drop nodes coupled using a first optical fiber ring and a second optical fiber ring. The method includes interrupting optical traffic travelling in a first direction on the first optical fiber ring at a first interruption location between a first passive add/drop node and a second passive add/drop node. The method further includes interrupting optical traffic travelling in a second disparate direction on the second optical fiber ring at a second interruption location between the first add/drop node and the second add/drop node. The network provides protection switching such that interrupting traffic flow at the first or second interruption locations does not prevent traffic on the network from reaching any add/drop node. The method also includes inserting an optical gateway node into the network.
    Type: Application
    Filed: February 10, 2004
    Publication date: August 11, 2005
    Inventors: Koji Takeguchi, Ashwin Gumaste, Susumu Kinoshita
  • Publication number: 20050117909
    Abstract: An optical cross-connect includes multiple input ports that each receive an optical input signal and multiple output ports that each output an optical output signal. The optical cross-connect also includes a distributing amplifier associated with each input port that generates multiple copies of the input signal received at the associated input port. Furthermore, the optical cross-connect includes multiple filter units that receive a copy of one or more of the input signals from one or more of the distributing amplifiers and forward traffic in selected channels of one or more of the received copies. In addition, the optical cross-connect includes a combining amplifier associated with each output port. Each combining amplifier receives the traffic in one or more of the channels forwarded by one or more of the filter units and combines the received traffic into an output signal to be output from the associated output port.
    Type: Application
    Filed: December 2, 2003
    Publication date: June 2, 2005
    Inventors: Yasuhiko Aoki, Susumu Kinoshita, Koji Takeguchi