Patents by Inventor Seiichi Sampei

Seiichi Sampei 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: 8451709
    Abstract: The invention provides precise estimation of a channel response and correct demodulation of an information signal even in the circumstance of being likely suffering interference. The invention includes an error correcting code unit 1, an S/P converting unit 2, a mapping unit 3, an IDFT (Inverse Discrete Fourier Transform) unit (IFFT: Inverse Fast Fourier Transform can be used) 4, a P/S converting unit 5, a GI (Guard Interval) inserting unit 6, preamble (A, B0, B1) storage selecting units 11-a and 11-b, switch units 12-a and 12-b, D/A converting units 13-a and 13-b, radio units 14-a and 14-b and antenna units 15-a and 15-b.
    Type: Grant
    Filed: January 16, 2006
    Date of Patent: May 28, 2013
    Assignees: Sharp Kabushiki Kaisha, Osaka University, National Institute of Information and Communications Technology
    Inventors: Yasuhiro Hamaguchi, Shimpei To, Hideo Nanba, Seiichi Sampei, Hiroshi Harada, Masafumi Moriyama
  • Publication number: 20130070867
    Abstract: Improving the accuracy of estimation of channel responses in receiving signals from a plurality of antennas is disclosed. A transmitting device of a base station includes a preamble A generating unit 010, a preamble B generating unit 011, phase rotating units 012 and 013, multiplexing units 014 and 015, an forward error correction coding unit 016, an S/P converting unit 017, a mapping unit 018, a changeover switch 019, IDFT (or IFFT) units 020 and 026, P/S converting units 021 and 027, GI (Guard Interval) inserting units 022 and 028, D/A converting units 023 and 029, radio transmitting units 024 and 030 and antenna units 025 and 031. In the preamble A generating unit 010 and the preamble B generating unit 011, a preamble A and a preamble B (see the packet format in FIG. 1) are generated, respectively. The preamble A is outputted to the multiplexing units 014 and 015, while the preamble B is outputted to the phase rotating units 012 and 013.
    Type: Application
    Filed: November 5, 2012
    Publication date: March 21, 2013
    Applicants: NATIONAL INSTITUTE OF INFORMATION AND COMMUNICATIONS TECHNOLOGY, SHARP KABUSHIKI KAISHA
    Inventors: Shimpei To, Yasuhiro Hamaguchi, Hideo Nanba, Seiichi Sampei, Hiroshi Harada, Masafumi Moriyama
  • Publication number: 20120324308
    Abstract: A communication device includes a turbo encoding section including a plurality of component encoders, wherein the plurality of component encoders within the turbo encoding section use different constraint lengths.
    Type: Application
    Filed: February 22, 2011
    Publication date: December 20, 2012
    Inventors: Jungo Goto, Yasuhiro Hamaguchi, Kazunari Yokomakura, Osamu Nakamura, Hiroki Takahashi, Shinsuke Ibi, Seiichi Sampei, Shinichi Miyamoto
  • Patent number: 8270514
    Abstract: Improving the accuracy of estimation of channel responses in receiving signals from a plurality of antennas is disclosed. A transmitting device of a base station includes a preamble A generating unit 010, a preamble B generating unit 011, phase rotating units 012 and 013, multiplexing units 014 and 015, an forward error correction coding unit 016, an S/P converting unit 017, a mapping unit 018, a changeover switch 019, IDFT (or IFFT) units 020 and 026, P/S converting units 021 and 027, GI (Guard Interval) inserting units 022 and 028, D/A converting units 023 and 029, radio transmitting units 024 and 030 and antenna units 025 and 031. In the preamble A generating unit 010 and the preamble B generating unit 011, a preamble A and a preamble B (see the packet format in FIG. 1) are generated, respectively. The preamble A is outputted to the multiplexing units 014 and 015, while the preamble B is outputted to the phase rotating units 012 and 013.
    Type: Grant
    Filed: January 16, 2006
    Date of Patent: September 18, 2012
    Assignees: Sharp Kabushiki Kaisha, National Institute of Information and Communications Technology
    Inventors: Shimpei To, Yasuhiro Hamaguchi, Hideo Nanba, Seiichi Sampei, Hiroshi Harada, Masafumi Moriyama
  • Publication number: 20120155373
    Abstract: A wireless communication system includes: a multiple number of mobile station apparatuses that transmit code bits obtained by applying error-correction coding to information bits; a relay station apparatus that receives code bits from the multiple mobile station apparatuses, applies network coding on the code bits and transmits the network-code bits; and a base station apparatus that receives and decodes the code bits and the network-code bits, wherein the base station apparatus, when decoding the received code bits, performs iteration decoding by regarding the received code bits as a serially concatenated code of network coding and error correction coding. Accordingly, decoding is performed by regarding the network code and the error correction code as a serial concatenated code, it is possible to obtain diversity with a simple configuration.
    Type: Application
    Filed: August 30, 2010
    Publication date: June 21, 2012
    Inventors: Kazunari Yokomakura, Yasuhiro Hamaguchi, Hiroki Takahashi, Jungo Goto, Osamu Nakamura, Shinsuke Ibi, Seiichi Sampei, Shinich Miyamoto
  • Publication number: 20120096336
    Abstract: To improve performance of a decoder even in a system with the coder configuration determined by inserting a doping bit sequence known between a transmission apparatus and a reception apparatus in an information bit sequence to transmit, the transmission apparatus is a transmission apparatus that transmits radio signals to the reception apparatus, and is provided with a doping section 23 that inserts a doping bit sequence which is known between the transmission apparatus and the reception apparatus in an information bit sequence to transmit to the reception apparatus, coding sections 11a, 11b that performerror-correcting coding on a bit sequence with the doping bit sequence inserted therein, a puncturing section that performs puncturing on a bit sequence subjected to the error-correcting coding, and a wireless transmission section 24 that transmits a bit sequence subjected to the puncturing.
    Type: Application
    Filed: March 3, 2010
    Publication date: April 19, 2012
    Inventors: Osamu Nakamura, Yasuhiro Hamaguchi, Kazunari Yokomakura, Jungo Goto, Hiroki Takahashi, Shinsuke Ibi, Seiichi Sampei, Shinichi Miyamoto
  • Publication number: 20120057543
    Abstract: Based on a data signal and a known reference signal, a frequency response of a channel is predicted, and the state of the channel over the entire transmission band is predicted such that frequency allocation is performed in a short period of time. A reception apparatus that receives a signal from a transmission apparatus which distributedly arranges signals in a frequency domain into a plurality of frequencies and which performs wireless transmission, the reception apparatus including: a channel property prediction unit (57) that predicts a channel property over an entire transmission band based on the distributedly arranged channel estimation reference signal; an allocation frequency determination unit (58) that determines the plurality of frequencies in which the signals in the frequency domain are distributedly arranged; and a frequency allocation information generation unit (59) that generates frequency allocation information indicating the determined plurality of frequencies.
    Type: Application
    Filed: March 3, 2010
    Publication date: March 8, 2012
    Applicants: OSAKA UNIVERSITY, SHARP KABUSHIKI KAISHA
    Inventors: Kazunari Yokomura, Yasuhiro Hamaguchi, Osamu Nakamura, Jungo Goto, Hiroki Takahashi, Shinsuke Ibi, Seiichi Sampei, Shinichi Miyamoto
  • Publication number: 20110320920
    Abstract: By controlling to select encoding appropriately considering characteristics of equalization and decoding of a receiving apparatus employing a turbo equalization technology, it is possible to attain a high transmission characteristic. Information bits of two systems including a sequence which is input to a first RSC encoding unit 22 and a sequence which is input through an interleaving unit 21 to a second RSC encoding unit 23 are set for input information bits, and each of which is subjected to RSC encoding. Each encoded parity bit is input to a puncturing unit 24. Since a systematic bit obtained by the first RSC encoding unit 22 is the information bit itself, a systematic bit obtained by the second RSC encoding unit 23 is not transmitted. In the puncturing unit 24, while puncturing is applied according to a predetermined coding rate, selection of either an RSC code or a turbo code is carried out by a puncturing control unit 25.
    Type: Application
    Filed: March 5, 2010
    Publication date: December 29, 2011
    Applicant: SHARP KABUSHIKI KAISHA
    Inventors: Seiichi Sampei, Shinsuke Ibi, Shinichi Miyamoto, Kazunari Yokomakura, Yasuhiro Hamaguchi, Osamu Nakamura, Takashi Yoshimoto, Ryota Yamada
  • Publication number: 20110299609
    Abstract: A transmission method according to the present invention has been conceived assuming an environment where two information source nodes independently communicate with one destination node, and thus is applicable to such a simple topology. The transmission method provides an inter-node cooperation relationship which provides a sufficient advantageous effect even in an environment in which there is a difference in the power levels of the received signals that reach the address node via two routes. The transmission method is performed by a node U1 (40) and a node U2 that is located closer to the node D (60) than the node U1 (40) to transmit signals to a node D (60) which iteratively detects a log likelihood ratio between mutually corresponding pairs of bits included in the signals at constellation points.
    Type: Application
    Filed: February 23, 2010
    Publication date: December 8, 2011
    Inventors: Shinsuke Ibi, Seiichi Sampei
  • Publication number: 20110212743
    Abstract: Each of first radio communication devices includes; a frequency spread unit which spreads frequency of a transmitted signal to generate a frequency-spread signal; and a mapping unit which allocates the frequency-spread signal to a subcarrier according to the mapping information which specifies a subcarrier. A second radio communication device includes: a demapping unit which extracts from a received signal a signal of the subcarrier specified by the mapping information; and an inverse frequency spread unit which inverse-frequency-spreads the extracted signal. The first radio communication device or the second radio communication device includes a use subcarrier decision unit that decides a subcarrier to which the frequency-spread-signal is allocated according to a communication path capacity of each subcarrier of each antenna used for transmission by the first radio communication devices and generates mapping information used to specify the decided subcarrier.
    Type: Application
    Filed: August 13, 2008
    Publication date: September 1, 2011
    Inventors: Kazunari Yokomakura, Yasuhiro Hamaguchi, Shimpei To, Minoru Kubota, Hideo Namba, Seiichi Sampei, Shinichi Miyamoto, Shinsuke Ibi
  • Publication number: 20110044377
    Abstract: A clipping rate is controlled in spectrum shaping according to a propagation path to thereby improve transmission characteristics and perform communication at a stable transmission rate. Propagation path characteristics are detected by a propagation path information detection unit 5 for detecting propagation path information fed back from a base station device and a water filling principle for distributing energy by a primary spectrum shaping unit 6 according to the propagation path characteristics is applied to transmission spectrum obtained by a DFT unit 4. Clipping information in secondary spectrum shaping fed back from the base station device is detected by a clipping information detection unit 7 to perform the secondary spectrum shaping by a secondary spectrum shaping unit 8. At this time, with the clipping rate by the secondary spectrum shaping unit 8, clipping rates of all transmission devices multiplexed in a scheduling unit 26 of the base station device are controlled adaptively.
    Type: Application
    Filed: April 22, 2009
    Publication date: February 24, 2011
    Inventors: Shinsuke Ibi, Seiichi Sampei, Shinichi Miyamoto, Kazunari Yokomakura, Minoru Kubota, Yasuhiro Hamaguchi, Shimpei To, Osamu Nakamura
  • Publication number: 20110032973
    Abstract: To provide a system that can accommodate a greater number of terminals within a limited band and can obtain a higher transmission rate. While the number of frequency signals (spectrums) output in parallel by performing a spread spectrum from the DFT unit of each terminal is 12, the number of sub-carriers constituting one sub-channel is set at 10 or 11. In this case, the users (users A and G) allocated to the sub-channels at both ends of the band will not perform transmission of one frequency signal at the end (one sub-carrier) of all the frequency signals output from the DFT unit, whereas the users (users B to F) allocated to the other sub-channels will not perform transmission of the frequency signals at the ends (two sub-carriers). This transmission can be realized by deleting (clipping) the associated number of signals from both ends or from one end of the frequency signals output from the DFT unit of each terminal and allocating the frequency signals after clipping, to individual sub-channels.
    Type: Application
    Filed: April 22, 2009
    Publication date: February 10, 2011
    Inventors: Shimpei To, Minoru Kubota, Yasuhiro Hamaguchi, Osamu Nakamura, Kazunari Yokomakura, Seiichi Sampei, Shinichi Miyamoto, Shinsuke Ibi
  • Publication number: 20100322073
    Abstract: The amount of information reported by a communication terminal apparatus to a communication control apparatus is reduced based on the congestion status of communication. Communication control 100 apparatus communicates with a communication terminal apparatus using frequency channels composed of two or more sub-channels defined by a predetermined frequency band includes: receiver 113 for receiving information data destined to the terminal apparatus; scheduler 113 for generating assignment information indicating the status of assignment of the received information data to each sub-channel; congestion information generator 103 for generating congestion information indicating the congestion degree of each sub-channel based on the generated assignment information; control information generator 104 for generating control information including the generated congestion information; and transmitter 111 for transmitting the generated control information to the terminal apparatus.
    Type: Application
    Filed: December 7, 2007
    Publication date: December 23, 2010
    Applicants: SHARP KABUSHIKI KAISHA, OSAKA UNIVERSITY, National Institute of Information and Communications Technology
    Inventors: Hideo NAMBA, Minoru KUBOTA, Yasuhiro HAMAGUCHI, Shimpei TO, Seiichi SAMPEI, Hiroshi HARADA
  • Publication number: 20100254497
    Abstract: Improving the accuracy of estimation of channel responses in receiving signals from a plurality of antennas is disclosed. A transmitting device of a base station includes a preamble A generating unit 010, a preamble B generating unit 011, phase rotating units 012 and 013, multiplexing units 014 and 015, an forward error correction coding unit 016, an S/P converting unit 017, a mapping unit 018, a changeover switch 019, IDFT (or IFFT) units 020 and 026, P/S converting units 021 and 027, GI (Guard Interval) inserting units 022 and 028, D/A converting units 023 and 029, radio transmitting units 024 and 030 and antenna units 025 and 031. In the preamble A generating unit 010 and the preamble B generating unit 011, a preamble A and a preamble B (see the packet format in FIG. 1) are generated, respectively. The preamble A is outputted to the multiplexing units 014 and 015, while the preamble B is outputted to the phase rotating units 012 and 013.
    Type: Application
    Filed: April 1, 2010
    Publication date: October 7, 2010
    Inventors: Shimpei TO, Yasuhiro HAMAGUCHI, Hideo NANBA, Seiichi SAMPEI, Hiroshi HARADA, Masafumi MORIYAMA
  • Publication number: 20100098177
    Abstract: A radio communication system converts a time domain signal into a plurality of frequency signals to be allocated onto a plurality of subcarriers to be transmitted. The radio communication system changes a method of allocating the plurality of frequency signals onto the plurality of subcarriers based on transmission power information.
    Type: Application
    Filed: December 27, 2007
    Publication date: April 22, 2010
    Inventors: Yasuhiro Hamaguchi, Minoru Kubota, Hideo Namba, Shimpei To, Seiichi Sampei, Shinichi Miyamoto
  • Patent number: 7436809
    Abstract: A communicating system is disclosed. The communicating system has a base station and a plurality of mobile stations that radio-communicate through an uplink channel and a downlink channel with frames each of which is composed of a plurality of time divided slots, each of the frames of the uplink channel and the downlink channel being transmitted in accordance with OFDM transmitting system. An OFDM sub carrier used in the OFDM transmitting system is divided in accordance with a predetermined diving method, each of the frames of the uplink channel or downlink channel being allocated to the divided portions of the OFDM sub carrier, a plurality of frames of the uplink channel or downlink channel being radio-communicated between one base station and a plurality of mobile stations.
    Type: Grant
    Filed: January 6, 2005
    Date of Patent: October 14, 2008
    Assignee: National Institute of Information and Communications Technology, Incorporated Administrative Agency
    Inventors: Hiroshi Harada, Chang-Jun Ahn, Satoshi Takahashi, Yukiyoshi Kamio, Seiichi Sampei
  • Publication number: 20080112309
    Abstract: The invention provides precise estimation of a channel response and correct demodulation of an information signal even in the circumstance of being likely suffering interference. The invention includes an error correcting code unit 1, an S/P converting unit 2, a mapping unit 3, an IDFT (Inverse Discrete Fourier Transform) unit (IFFT: Inverse Fast Fourier Transform can be used) 4, a P/S converting unit 5, a GI (Guard Interval) inserting unit 6, preamble (A, B0, B1) storage selecting units 11-a and 11-b, switch units 12-a and 12-b, D/A converting units 13-a and 13-b, radio units 14-a and 14-b and antenna units 15-a and 15-b.
    Type: Application
    Filed: January 16, 2006
    Publication date: May 15, 2008
    Inventors: Yasuhiro Hamaguchi, Shimpei To, Hideo Nanba, Seiichi Sampei, Hiroshi Harada, Masafumi Moriyama
  • Publication number: 20080080628
    Abstract: Improving the accuracy of estimation of channel responses in receiving signals from a plurality of antennas is disclosed. A transmitting device of a base station includes a preamble A generating unit 010, a preamble B generating unit 011, phase rotating units 012 and 013, multiplexing units 014 and 015, an forward error correction coding unit 016, an S/P converting unit 017, a mapping unit 018, a changeover switch 019, IDFT (or IFFT) units 020 and 026, P/S converting units 021 and 027, GI (Guard Interval) inserting units 022 and 028, D/A converting units 023 and 029, radio transmitting units 024 and 030 and antenna units 025 and 031. In the preamble A generating unit 010 and the preamble B generating unit 011, a preamble A and a preamble B (see the packet format in FIG. 1) are generated, respectively. The preamble A is outputted to the multiplexing units 014 and 015, while the preamble B is outputted to the phase rotating units 012 and 013.
    Type: Application
    Filed: January 16, 2006
    Publication date: April 3, 2008
    Inventors: Shimpei To, Yasuhiro Hamaguchi, Hideo Nanba, Seiichi Sampei, Hiroshi Harada, Masafumi Moriyama
  • Publication number: 20070004437
    Abstract: A communicating system is disclosed. The communicating system has a base station and a plurality of mobile stations that radio-communicate through an uplink channel and a downlink channel with frames each of which is composed of a plurality of time divided slots, each of the frames of the uplink channel and the downlink channel being transmitted in accordance with OFDM transmitting system. An OFDM sub carrier used in the OFDM transmitting system is divided in accordance with a predetermined diving method, each of the frames of the uplink channel or downlink channel being allocated to the divided portions of the OFDM sub carrier, a plurality of frames of the uplink channel or downlink channel being radio-communicated between one base station and a plurality of mobile stations.
    Type: Application
    Filed: January 6, 2005
    Publication date: January 4, 2007
    Inventors: Hiroshi Harada, Chang-Jun Ahn, Satoshi Takahashi, Yukiyoshi Kamio, Seiichi Sampei
  • Patent number: 4899367
    Abstract: A multi-level quadrature amplitude modulator system that can be used in communication channels in which there is intense fluctuation has a transmitter section that is provided with a frame synchronizer that inserts a reference symbol into each group of message symbols, and a receiving section that is provided with an estimator for the transmission path distortion in the message symbols on the basis of distortion found in the reference symbols. The receiving section is also provided with a compensator for the distortion thus described.
    Type: Grant
    Filed: February 2, 1989
    Date of Patent: February 6, 1990
    Assignee: Communications Research Laboratory Ministry of Posts and Telecommunications
    Inventor: Seiichi Sampei