Patents by Inventor Tatsuhiro Nakada

Tatsuhiro Nakada 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: 20190044651
    Abstract: A terminal apparatus (1) is provided with a coding unit (7), a decoding unit (2), and a control unit (5) for controlling the coding unit and the decoding unit individually. Under control of the control unit, the coding unit codes a payload, a first number of error corrections (3), and identification information (6) that are to be transmitted, on the basis of a method indicated by the already-transmitted identification information to thereby generate first coded data. The decoding unit decodes newly-received second coded data on the basis of a method indicated by the identification information included in a decoding result of the already-received second coded data.
    Type: Application
    Filed: September 16, 2016
    Publication date: February 7, 2019
    Applicant: NEC Corporation
    Inventor: Tatsuhiro NAKADA
  • Patent number: 9967113
    Abstract: Disclosed is a reception apparatus that has solved a problem that fluctuations cannot be followed immediately after a commencement of turbo equalization in a high-speed fading environment. A reception apparatus includes a soft interference canceller, an MMSE equalizer, a likelihood calculator, a de-interleaver, an SISO decoder, an information bit hard decision unit, a subtracter, an interleaver, a soft estimation value calculator, a zero storage unit, a known signal memory unit, a transmission path estimator, and a plurality of switches. At the time of equalization, the transmission path estimator uses, as a reference signal, a known signal stored in the known signal memory unit or an output of the MMSE equalizer. Meanwhile, at the time of a first equalization, the soft interference canceller is given a ‘0’ value from the zero storage unit as a reference signal.
    Type: Grant
    Filed: September 15, 2016
    Date of Patent: May 8, 2018
    Assignee: HITACHI KOKUSAI ELECTRIC INC.
    Inventors: Kei Ito, Keisuke Yamamoto, Tatsuhiro Nakada
  • Patent number: 9882671
    Abstract: An optical signal transmitted by another terminal device that was used for compensation could be received by a device that is not the intended destination of said optical signal, resulting in the problem that confidentiality cannot be guaranteed for the information in said optical signal. This optical reception device is characterized by the provision of the following: a receiving means via which wavelength-multiplexed signal light is inputted; and a transmitting means that, in accordance with an identifier in an optical signal of a prescribed wavelength in the inputted wavelength-multiplexed signal light, forwards said optical signal.
    Type: Grant
    Filed: September 11, 2014
    Date of Patent: January 30, 2018
    Assignee: NEC Corporation
    Inventor: Tatsuhiro Nakada
  • Patent number: 9853700
    Abstract: An object of the present invention is to generate a soft estimation value where missing of bit information is avoided and to implement turbo equalization processing in a wireless transmission apparatus and a wireless transmission system where termination processing is not performed in an error correction coding part and interleave processing over frames is performed. A wireless transmission system of the present invention includes a transmission apparatus and a reception apparatus. The transmission apparatus includes an error correction coding unit, a first interleave unit, a second interleave unit, and a digital modulation unit. The reception apparatus includes a unit that detects a reception signal, a demapper unit, a second deinterleave unit, a unit to store a received bit logarithm of likelihood ratio in a frame buffer, a frequency interleaver data extraction part that extracts data of a predetermined period, a decoding part, and a hard decision part.
    Type: Grant
    Filed: March 15, 2017
    Date of Patent: December 26, 2017
    Assignee: Hitachi Kokusai Electric Inc.
    Inventors: Daiki Hoshi, Tatsuhiro Nakada, Kei Ito
  • Publication number: 20170187434
    Abstract: An object of the present invention is to generate a soft estimation value where missing of bit information is avoided and to implement turbo equalization processing in a wireless transmission apparatus and a wireless transmission system where termination processing is not performed in an error correction coding part and interleave processing over frames is performed. A wireless transmission system of the present invention includes a transmission apparatus and a reception apparatus. The transmission apparatus includes an error correction coding unit, a first interleave unit, a second interleave unit, and a digital modulation unit. The reception apparatus includes a unit that detects a reception signal, a demapper unit, a second deinterleave unit, a unit to store a received bit logarithm of likelihood ratio in a frame buffer, a frequency interleaver data extraction part that extracts data of a predetermined period, a decoding part, and a hard decision part.
    Type: Application
    Filed: March 15, 2017
    Publication date: June 29, 2017
    Inventors: Daiki HOSHI, Tatsuhiro NAKADA, Kei ITO
  • Patent number: 9608861
    Abstract: A first terminal-side routing control device 13 is placed between a first communication network 21 and a first communication terminal 11. A second terminal-side routing control device 15 is placed between a second communication network 22 and a second communication terminal 12. The first terminal-side routing control device 13 includes a first via information setting unit 14 for including, in data received from the first communication terminal 11, information for specifying a routing control device 33 placed on one side of a long-distance transmission path 23 as a via device. The second terminal-side routing control device 15 includes a second via information setting unit 16 for including, in data received from the second communication terminal 12, via information for specifying a routing control device 34 placed on the other side of the long-distance transmission path 23 as a via device.
    Type: Grant
    Filed: July 19, 2012
    Date of Patent: March 28, 2017
    Assignee: NEC CORPORATION
    Inventor: Tatsuhiro Nakada
  • Publication number: 20170005840
    Abstract: Disclosed is a reception apparatus that has solved a problem that fluctuations cannot be followed immediately after a commencement of turbo equalization in a high-speed fading environment. A reception apparatus includes a soft interference canceller, an MMSE equalizer, a likelihood calculator, a de-interleaver, an SISO decoder, an information bit hard decision unit, a subtracter, an interleaver, a soft estimation value calculator, a zero storage unit, a known signal memory unit, a transmission path estimator, and a plurality of switches. At the time of equalization, the transmission path estimator uses, as a reference signal, a known signal stored in the known signal memory unit or an output of the MMSE equalizer. Meanwhile, at the time of a first equalization, the soft interference canceller is given a ‘0’ value from the zero storage unit as a reference signal.
    Type: Application
    Filed: September 15, 2016
    Publication date: January 5, 2017
    Inventors: Kei ITO, Keisuke YAMAMOTO, Tatsuhiro NAKADA
  • Patent number: 9461681
    Abstract: A receiver includes a first and a second amplification unit for amplifying a first and second received signals received by antenna units; a level variation detection unit for performing gain control of the first amplification unit; a maximum received signal level extraction unit for performing gain control of the second amplification unit; and a first and a second frequency conversion unit.
    Type: Grant
    Filed: June 1, 2016
    Date of Patent: October 4, 2016
    Assignee: HITACHI KOKUSAI ELECTRIC INC.
    Inventors: Hiroki Kato, Tatsuhiro Nakada
  • Publication number: 20160277050
    Abstract: A receiver includes a first and a second amplification unit for amplifying a first and second received signals received by antenna units; a level variation detection unit for performing gain control of the first amplification unit; a maximum received signal level extraction unit for performing gain control of the second amplification unit; and a first and a second frequency conversion unit.
    Type: Application
    Filed: June 1, 2016
    Publication date: September 22, 2016
    Inventors: Hiroki KATO, Tatsuhiro NAKADA
  • Patent number: 9444671
    Abstract: The present invention makes it possible to maintain the continuity of reception detection level and adjust the direction of a reception antenna even under the condition that the reception electric field is low and clock timing synchronization at a C/N ratio of 0 dB or less is lost. QAM modulation including a pilot carrier has higher correlativity in one symbol (1152 samples) correlation, and differential modulation with no pilot has higher correlativity in effective symbol (1024 samples) correction. Detection circuits are provided separately for the QAM modulation and the differential modulation, and in the differential modulation, autocorrelation with a 1024 FFT clock delay signal is performed. The higher of the respective correlation results is selected in the final stage.
    Type: Grant
    Filed: March 28, 2014
    Date of Patent: September 13, 2016
    Assignee: Hitachi Kokusai Electric Inc.
    Inventors: Mikio Fujikura, Tatsuhiro Nakada
  • Publication number: 20160261363
    Abstract: An optical signal transmitted by another terminal device that was used for compensation could be received by a device that is not the intended destination of said optical signal, resulting in the problem that confidentiality cannot be guaranteed for the information in said optical signal. This optical reception device is characterized by the provision of the following: a receiving means via which wavelength-multiplexed signal light is inputted; and a transmitting means that, in accordance with an identifier in an optical signal of a prescribed wavelength in the inputted wavelength-multiplexed signal light, forwards said optical signal.
    Type: Application
    Filed: September 11, 2014
    Publication date: September 8, 2016
    Applicant: NEC Corporation
    Inventor: Tatsuhiro NAKADA
  • Publication number: 20160149741
    Abstract: The present invention makes it possible to maintain the continuity of reception detection level and adjust the direction of a reception antenna even under the condition that the reception electric field is low and clock timing synchronization at a C/N ratio of 0 dB or less is lost. QAM modulation including a pilot carrier has higher correlativity in one symbol (1152 samples) correlation, and differential modulation with no pilot has higher correlativity in effective symbol (1024 samples) correction. Detection circuits are provided separately for the QAM modulation and the differential modulation, and in the differential modulation, autocorrelation with a 1024 FFT clock delay signal is performed. The higher of the respective correlation results is selected in the final stage.
    Type: Application
    Filed: March 28, 2014
    Publication date: May 26, 2016
    Inventors: Mikio FUJIKURA, Tatsuhiro NAKADA
  • Publication number: 20140369181
    Abstract: A first terminal-side routing control device 13 is placed between a first communication network 21 and a first communication terminal 11. A second terminal-side routing control device 15 is placed between a second communication network 22 and a second communication terminal 12. The first terminal-side routing control device 13 includes a first via information setting unit 14 for including, in data received from the first communication terminal 11, information for specifying a routing control device 33 placed on one side of a long-distance transmission path 23 as a via device. The second terminal-side routing control device 15 includes a second via information setting unit 16 for including, in data received from the second communication terminal 12, via information for specifying a routing control device 34 placed on the other side of the long-distance transmission path 23 as a via device.
    Type: Application
    Filed: July 19, 2012
    Publication date: December 18, 2014
    Applicant: NEC Corporation
    Inventor: Tatsuhiro Nakada
  • Patent number: 8761605
    Abstract: Even in a network system including a transmission line of which dominant cause of delay is a transmission line delay, controlling communication speed of the network system as a whole efficiently and suppressing the delay is made possible.
    Type: Grant
    Filed: September 21, 2010
    Date of Patent: June 24, 2014
    Assignee: NEC Corporation
    Inventors: Tatsuhiro Nakada, Yohei Hasegawa
  • Publication number: 20120230671
    Abstract: Even in a network system including a transmission line of which dominant cause of delay is a transmission line delay, controlling communication speed of the network system as a whole efficiently and suppressing the delay is made possible.
    Type: Application
    Filed: September 21, 2010
    Publication date: September 13, 2012
    Applicant: NEC CORPORATION
    Inventors: Tatsuhiro Nakada, Yohei Hasegawa
  • Patent number: 7681713
    Abstract: An upstream side wheel includes grippers B which do not perform opening and closing operations for themselves, and a downstream side wheel includes grippers A each having an opening and closing mechanism, and in a delivery position in which both the wheels are adjacent to each other, a plastic bottle 1 is delivered from the gripper B to the gripper A. Here, if the upstream side wheel or the downstream side wheel abnormally stops, the grippers A are switched from a use state to a retreat state. Thereby, interference between plastic bottles gripped by the upstream side grippers and the grippers of the downstream side wheel is avoided. Even if one of the wheels abnormally stops, the other wheel can be continuously operated without increasing the equipment in size.
    Type: Grant
    Filed: February 19, 2008
    Date of Patent: March 23, 2010
    Assignee: Shibuya Kogyo Co., Ltd.
    Inventors: Tokuo Nishi, Koji Kaya, Tatsuhiro Nakada, Hideki Nishikawa, Takashi Shimomura
  • Patent number: 7483368
    Abstract: A TMCC carrier is demodulated from a received OFDM signal having a TMCC carrier. A relative carrier position of the demodulated TMCC carrier is detected. A carrier shift amount is detected from the detected relative carrier position of the TMCC carrier and a normal TMCC carrier position. The received OFDM signal is corrected for the carrier frequency shift based on the detected carrier shift amount.
    Type: Grant
    Filed: September 16, 2004
    Date of Patent: January 27, 2009
    Assignee: Hitachi Kokusai Electric Inc.
    Inventors: Hiroyuki Takesue, Tatsuhiro Nakada, Nobuo Tsukamoto
  • Publication number: 20080223691
    Abstract: An upstream side wheel Ha including grippers B which do not perform opening and closing operations for themselves, and a downstream side wheel Hb including grippers A each having an opening and closing mechanism are included, and in a delivery position in which both the wheels are adjacent to each other, a plastic bottle 1 is delivered from the gripper B to the gripper A. Here, if the upstream side wheel or the downstream side wheel abnormally stops, control means controls retreating means C provided at the downstream side wheel to switch the grippers A to a retreat state from a use state to make an opening degree of a first and second grip members 23 and 24 of each of the grippers A larger than an opening degree of both the grip members in the use state. Thereby, interference of the plastic bottles gripped by the upstream side grippers and the first and second grip members can be prevented.
    Type: Application
    Filed: February 19, 2008
    Publication date: September 18, 2008
    Inventors: Tokuo Nishi, Koji Kaya, Tatsuhiro Nakada, Hideki Nishikawa, Takashi Shimomura
  • Publication number: 20080118244
    Abstract: An RPR network system provides redundancy to the RPR function, at occurrence of failure in an RPR node device, to communicate with RPR node devices other than the failed device on an RPR ring and redundancy to an ethernet (registered trademark) port function to communicate a MAC frame via ports. The system includes a plurality of node devices connected on a link to each other in which two adjacent RPR node devices, i.e., first and second node devices, cooperatively operate as one virtual RPR node device. The first node device is set as a master device to communicate as the virtual RPR node device with other RPR node devices and the second node device is set as a slave device not to communicate as the virtual RPR node device with other RPR node devices, the master and slave devices being replaceable by each other. Either one of ports belonging respectively to the master and slave devices is capable of outputting data therefrom.
    Type: Application
    Filed: November 13, 2007
    Publication date: May 22, 2008
    Applicant: NEC CORPORATION
    Inventor: Tatsuhiro Nakada
  • Patent number: 7020116
    Abstract: A data transmission apparatus employing an orthogonal frequency division multiplex system. A receiver included therein analyzes a cross-correlation value sequence signal (CT) which has been acquired from the arithmetic operation of the correlation between a received signal and a predetermined symbol signal to detect an effective correlation peak in which the inter-symbol interference becomes minimum, and on the basis of the effective correlation peak thus detected, carries out the processing of synchronizing a reception sampling clock, and the control for the frame timing and the symbol timing of the receiver.
    Type: Grant
    Filed: September 29, 2000
    Date of Patent: March 28, 2006
    Assignee: Hitachi Denshi Kabushiki Kaisha
    Inventor: Tatsuhiro Nakada