Patents by Inventor Koji Asahi

Koji Asahi 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).

  • Patent number: 11747175
    Abstract: A utility pole location specifying system according to the present disclosure includes a cable (20) containing a communication optical fiber disposed in a utility pole (10), a receiving unit (331) configured to receive an optical signal containing a characteristic pattern of the utility pole (10) from at least one communication optical fiber contained in the cable (20), and a specifying unit (332) configured to specify a location of the utility pole (10) based on the characteristic pattern.
    Type: Grant
    Filed: April 8, 2019
    Date of Patent: September 5, 2023
    Assignee: NEC CORPORATION
    Inventors: Yukihide Yoda, Yoshiaki Aono, Koji Asahi
  • Patent number: 11561118
    Abstract: A state specifying system according to the present disclosure includes a cable (20) disposed in a utility pole (10), the cable (20) containing a communication optical fiber, a receiving unit (331) configured to receive an optical signal from at least one optical fiber contained in the cable (20), and a specifying unit (332) configured to specify a state of the utility pole (10) or an environmental state around the utility pole (10) corresponding to a pattern of the optical signal received by the receiving unit (331).
    Type: Grant
    Filed: April 25, 2019
    Date of Patent: January 24, 2023
    Assignee: NEC CORPORATION
    Inventors: Yukihide Yoda, Yoshiaki Aono, Koji Asahi
  • Publication number: 20220172479
    Abstract: A monitoring system according to the present disclosure includes an optical fiber (10) laid in a monitoring area; an authenticating unit (20) configured to authenticate a person or a vehicle passing through a gate (G) for entering the monitoring area; an optical fiber sensing unit (31) configured to acquire, based on an optical signal received from the optical fiber (10), a parameter having a unique pattern corresponding to the pattern of action of the authenticated person or vehicle; and an analyzing unit (32) configured to identify the pattern of action of the authenticated person or vehicle based on the unique pattern of the parameter.
    Type: Application
    Filed: January 14, 2020
    Publication date: June 2, 2022
    Applicant: NEC Corporation
    Inventors: Yukihide YODA, Yoshiaki AONO, Koji ASAHI
  • Publication number: 20220171082
    Abstract: A monitoring system according to the present disclosure includes an optical fiber (10) laid on a ground or a seabed, an optical fiber sensing unit (21) configured to receive an optical signal from the optical fiber (10) and detect a vibration produced in the ground or the seabed based on the optical signal, and an analyzing unit (22) configured to identify a natural phenomenon that has caused the detected vibration based on a unique pattern of the detected vibration.
    Type: Application
    Filed: December 13, 2019
    Publication date: June 2, 2022
    Applicant: NEC Corporation
    Inventors: Yukihide YODA, Yoshiaki AONO, Koji ASAHI
  • Publication number: 20210247214
    Abstract: A state specifying system according to the present disclosure includes a cable (20) disposed in a utility pole (10), the cable (20) containing a communication optical fiber, a receiving unit (331) configured to receive an optical signal from at least one optical fiber contained in the cable (20), and a specifying unit (332) configured to specify a state of the utility pole (10) or an environmental state around the utility pole (10) corresponding to a pattern of the optical signal received by the receiving unit (331).
    Type: Application
    Filed: April 25, 2019
    Publication date: August 12, 2021
    Applicant: NEC Corporation
    Inventors: Yukihide YODA, Yoshiaki AONO, Koji ASAHI
  • Publication number: 20210247215
    Abstract: A utility pole deterioration detection system includes a cable (20) disposed in a utility pole (10), the cable (20) containing a communication optical fiber, a receiving unit (331) configured to receive an optical signal containing a pattern that changes according to a deterioration state of the utility pole (10) from at least one optical fiber contained in the cable (20), and a detection unit (332) configured to detect a deterioration state of the utility pole (10) based on the pattern.
    Type: Application
    Filed: April 23, 2019
    Publication date: August 12, 2021
    Applicant: NEC Corporation
    Inventors: Yukihide YODA, Yoshiaki AONO, Koji ASAHI
  • Publication number: 20210172767
    Abstract: A utility pole location specifying system according to the present disclosure includes a cable (20) containing a communication optical fiber disposed in a utility pole (10), a receiving unit (331) configured to receive an optical signal containing a characteristic pattern of the utility pole (10) from at least one communication optical fiber contained in the cable (20), and a specifying unit (332) configured to specify a location of the utility pole (10) based on the characteristic pattern.
    Type: Application
    Filed: April 8, 2019
    Publication date: June 10, 2021
    Applicant: NEC Corporation
    Inventors: Yukihide YODA, Yoshiaki AONO, Koji ASAHI
  • Patent number: 7649162
    Abstract: The present invention is to provide an optical feedback control unit for determining an optical output by a feedback control, an optical communication system, a feedback control method, and a recording medium for recording a program. According to the present invention, even when used in the system to which a plurality of nodes are connected, the unstable system may become stable by the proper feedback control without being affected by the optical level change according to the polarized variation or the loss variation.
    Type: Grant
    Filed: March 7, 2008
    Date of Patent: January 19, 2010
    Inventors: Takefumi Oguma, Hiroki Rikiyama, Koji Asahi
  • Publication number: 20080217511
    Abstract: The present invention is to provide an optical feedback control unit for determining an optical output by a feedback control, an optical communication system, a feedback control method, and a recording medium for recording a program. According to the present invention, even when used in the system to which a plurality of nodes are connected, the unstable system may become stable by the proper feedback control without being affected by the optical level change according to the polarized variation or the loss variation.
    Type: Application
    Filed: March 7, 2008
    Publication date: September 11, 2008
    Inventors: TAKEFUMI OGUMA, Hiroki Rikiyama, Koji Asahi
  • Patent number: 7350881
    Abstract: In a motorcycle provided with an antilock brake system, a front fork supporting a front wheel of a motorcycle is supported to be rotatable by a head pipe which is located at the front end portion of a body frame of a motorcycle, a handle-bar is secured to an upper end portion of the head pipe, master cylinders attached to the handle-bar are connected to hydraulic wheel brakes, respectively, via brake pipes. An antilock brake system includes an ABS-unit for antilock control disposed in an intermediate portion of the brake pipes. The ABS-unit is disposed immediately behind the head pipe and between a pair of body frame components disposed on both lateral sides of the motorcycle body and extending, from the head pipe, obliquely downward and backward, while extending outward in directions opposite to each other in the width direction of the motorcycle body.
    Type: Grant
    Filed: December 16, 2004
    Date of Patent: April 1, 2008
    Assignee: Suzuki Kabushiki Kaisha
    Inventor: Koji Asahi
  • Patent number: 7339723
    Abstract: An optical transmission system includes an optical fiber transmission line, one or more optical repeating apparatuses, an optical receiving apparatus, and a transferring route for transferring a supervisory signal based on a quality deterioration of an optical signal detected by the optical receiving apparatus to the optical repeating apparatus from the optical receiving apparatus. The optical repeating apparatus includes an optical level variation detecting unit for detecting a level variation of an optical signal and a level variation storing unit for storing information based on the level variation.
    Type: Grant
    Filed: March 25, 2005
    Date of Patent: March 4, 2008
    Assignee: NEC Corporation
    Inventor: Koji Asahi
  • Publication number: 20050220387
    Abstract: An optical transmission system includes an optical fiber transmission line, one or more optical repeating apparatuses, an optical receiving apparatus, and a transferring route for transferring a supervisory signal based on a quality deterioration of an optical signal detected by the optical receiving apparatus to the optical repeating apparatus from the optical receiving apparatus. The optical repeating apparatus includes an optical level variation detecting unit for detecting a level variation of an optical signal and a level variation storing unit for storing information based on the level variation.
    Type: Application
    Filed: March 25, 2005
    Publication date: October 6, 2005
    Applicant: NEC Corporation
    Inventor: Koji Asahi
  • Publication number: 20050134114
    Abstract: In a motorcycle provided with an antilock brake system, a front fork supporting a front wheel of a motorcycle is supported to be rotatable by a head pipe which is located at the front end portion of a body frame of a motorcycle, a handle-bar is secured to an upper end portion of the head pipe, master cylinders attached to the handle-bar are connected to hydraulic wheel brakes, respectively, via brake pipes. An antilock brake system includes an ABS-unit for antilock control disposed in an intermediate portion of the brake pipes. The ABS-unit is disposed immediately behind the head pipe and between a pair of body frame components disposed on both lateral sides of the motorcycle body and extending, from the head pipe, obliquely downward and backward, while extending outward in directions opposite to each other in the width direction of the motorcycle body.
    Type: Application
    Filed: December 16, 2004
    Publication date: June 23, 2005
    Applicant: SUZUKI KABUSHIKI KAISHA
    Inventor: Koji Asahi
  • Patent number: 6724953
    Abstract: To provide an optical cross-connect apparatus capable of, even in the case where a light switch becomes large-sized, supervising quality and management information of light signals passing through inside the apparatus with low-cost configuration. For each of the light signals inputted from n pieces of input port, path setting in a branch connection state is performed in order following a control signal from a control section by connecting any one of n pieces of output port with a predetermined supervising port at n×m light SW. Quality and management information are detected from light signals outputted from a supervising output port at a light signal detecting section, and the quality and the management information are supervised at a light signal supervising section.
    Type: Grant
    Filed: March 12, 2001
    Date of Patent: April 20, 2004
    Assignee: NEC Corporation
    Inventor: Koji Asahi
  • Patent number: 6704508
    Abstract: An optical crossconnect selectively connects at least one input terminal with at least one output terminal. The optical crossconnect includes: an optical switch connecting at least one input port connected to the at least one input terminal with at least one output port connected to the at least one output terminal; at least one supervisory light generating circuit for sending a supervisory light from each of the at least one output port to the optical switch; and at least one supervisory light receiving circuit for receiving the supervisory light output from the at least one input port.
    Type: Grant
    Filed: June 15, 2000
    Date of Patent: March 9, 2004
    Assignee: NEC Corporation
    Inventor: Koji Asahi
  • Patent number: 6619867
    Abstract: An optical transmission system capable of alleviating the non-linear optical effect from overhead portions of a bit pattern comprised of a plurality of bits, wherein a plurality of optical transmit devices input a clock signal of identical phase and frequency, and optical signals whose overhead positions are changed on each wavelength by respective variable delay lines under the control of a phase controller are sent to a transmit side WDM device. At the transmit side WDM device, these optical signals are multiplexed in a wavelength multiplexer and sent to the receive side WDM device. Receive side optical transmission devices receive the respectively isolated optical signals. A phase controller offsets the positions of the optical signals and sends them to the overhead on each wavelength so that the non-linear effect of the receive optical signal is suppressed and a satisfactory signal can be received.
    Type: Grant
    Filed: May 30, 2000
    Date of Patent: September 16, 2003
    Assignee: NEC Corporation
    Inventor: Koji Asahi
  • Patent number: 6595821
    Abstract: A high-quality and high-reliability rotary anode target for X-ray tubes, of which the mechanical strength at high temperatures is increased and which is applicable not only to low-speed rotation (at least 3,000 rpm) but also even to high-speed rotation at high temperatures, and also a method for producing it. The rotary anode has a two-layered structure to be formed by laminating an Mo alloy substrate that comprises from 0.2% by weight to 1.5% by weight of TiC with the balance of substantially Mo, and an X-ray generating layer of a W—Re alloy that overlies the substrate.
    Type: Grant
    Filed: April 20, 2001
    Date of Patent: July 22, 2003
    Assignee: Tokyo Tungsten Co., Ltd.
    Inventors: Masayuki Itoh, Koji Asahi, Mitsuo Osada, Yoshinari Amano, Tomohiro Takida
  • Patent number: 6570685
    Abstract: Each node of an optical ring system having m nodes connected multiplexes wavelengths of &lgr;1 to &lgr;n in optical wavelength division and transmits signals. This optical ring system is composed of working optical fibers (102-1 and 102-2) and protection optical fibers (102-3 and 102-4). Each node is composed of 4×4 optical switches (111 and 112), a first optical preamplifier (151), a first wavelength demultiplexer (152), a first wavelength multiplexer (153), a first optical booster amplifier (154), a second optical preamplifier (155), a second wavelength demultiplexer (156), a second wavelength multiplexer (157), a second optical booster amplifier (158), a third optical preamplifier (159), a third wavelength demultiplexer (160), a third wavelength multiplexer (161), a third optical booster amplifier (162), a fourth optical preamplifier (163), a fourth wavelength demultiplexer (164), a fourth wavelength multiplexer (165), a fourth optical booster amplifier (166), and line terminals (167-1 to 167-3).
    Type: Grant
    Filed: February 23, 1999
    Date of Patent: May 27, 2003
    Assignee: NEC Corporation
    Inventors: Sadao Fujita, Koji Asahi
  • Patent number: 6532089
    Abstract: An optical cross-connect has a plurality of input terminals to which photo signals are respectively inputted, a plurality of output terminals for respectively outputting the photo signals, and an optical switch for switching over an optical path between the input terminal and the output terminal. The optical switch, when switching over an optical path to a switchover target output terminal to which the optical path is newly connected from a pre-switchover output terminal through which the optical path is connected to the input terminal before the switchover, temporarily connects the optical path to both of the pre-switchover output terminal and the switchover target output terminal with a bridge connecting function. First and second monitor circuits for monitoring a state of the photo signal are disposed, respectively, between the input terminal and the optical switch, and between the optical switch and the output terminal.
    Type: Grant
    Filed: August 19, 1999
    Date of Patent: March 11, 2003
    Assignee: NEC Corporation
    Inventor: Koji Asahi
  • Patent number: 6337886
    Abstract: A receiving apparatus includes a counter for counting for a prescribed period of time the number of bits having one of two different levels, out of bits forming a digital signal which is entered and having the two different levels, and supplying a count signal, a bit rate detector for calculating the bit rate of the digital signal from the count signal and supplying a multiplying factor selection signal, a differentiating circuit, into which the input digital signal is entered, for supplying a pulse signal at a varying point of the input digital signal, a rectifying circuit for accomplishing full-wave rectification of the pulse signal, and supplying a rectified pulse signal, a band-pass filter for passing harmonics of the clock component of the input digital signal contained in the rectified pulse signal, and a frequency dividing circuit, into which the harmonics are entered, for frequency-dividing the harmonics by a ratio set on the basis of the multiplying factor selection signal, and supplying a resultant
    Type: Grant
    Filed: May 11, 1998
    Date of Patent: January 8, 2002
    Assignee: NEC Corporation
    Inventor: Koji Asahi