Patents by Inventor Katsuhiko Tsunehara

Katsuhiko Tsunehara 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: 20100034078
    Abstract: In a method by which a base station detects a random access signal transmitted by a user equipment to send a transmission request to the base station in uplinks, the base station omits a MF used only to detect the random access signal, or Fourier transform and inverse Fourier transform meeting the random access signal, and uses a Fourier transform unit for data reception to detect the random access signal. Using output of the Fourier transform unit for data reception, which transmits all received signals to frequency region signals, it is judged whether a random access signal is received by a power pattern of bands allocated to the random access signals in one transmission time interval.
    Type: Application
    Filed: August 5, 2009
    Publication date: February 11, 2010
    Applicant: HITACHI KOKUSAI ELECTRIC INC.
    Inventors: Yunjian JIA, Katsuhiko TSUNEHARA
  • Publication number: 20090307567
    Abstract: The error correction capability for wireless communication carried out involving propagation path fluctuation in time and frequency selectivity can be improved. A soft decision likelihood value inputted to an error correction decoder is multiplied by a weight determined according to the distance between the data symbol and pilot symbol corresponding to the soft decision likelihood value. Namely, the soft decision bit likelihood value corresponding to the data symbol is weighted according to the distances in time or frequency between the pilot symbol and data symbol. The weight is made smaller when the distance in time or frequency is larger.
    Type: Application
    Filed: May 28, 2009
    Publication date: December 10, 2009
    Applicant: HITACHI KOKUSAI ELECTRIC INC.
    Inventors: Katsuhiko Tsunehara, Yunjian Jia
  • Patent number: 7609197
    Abstract: By using the delay profile created by delay profile creating section 102 and the first threshold value 330 received from the first threshold value calculation 105, the first threshold value timing detection section 103 selects only the earliest receive timing exceeding the first threshold value, from all the timing that the correlation value in the delay profile becomes a maximum. By using the receive timing and the second threshold value 331 received from the second threshold value calculation section 107, reference timing calculation section 106 selects the reference timing required for calculating the receive timing for the incoming wave of the minimum propagation delay time. The timing delayed by previously set timing behind said reference timing is sent from receive timing calculation section 108 as the receive timing 113 of the incoming wave of the minimum propagation delay time.
    Type: Grant
    Filed: February 17, 2005
    Date of Patent: October 27, 2009
    Assignee: Hitachi, Ltd.
    Inventors: Katsuhiko Tsunehara, Nobukazu Doi, Mikio Kuwahara, Tomoaki Ishifuji
  • Publication number: 20090232236
    Abstract: In a cellular radio communication system, a base station or a mobile station has a TA (Time Alignment)-range-out detection function, so that when a TA-range-out state that is unable to compensate with a guard interval is detected, the transmission condition of an uplink signal at the mobile station is changed by the mobile station autonomously or by the base station and the mobile station cooperatively.
    Type: Application
    Filed: February 24, 2009
    Publication date: September 17, 2009
    Inventors: Tomonori YAMAMOTO, Katsuhiko Tsunehara, Satoshi Tamaki, May Takada, Mikio Kuwahara
  • Patent number: 7403580
    Abstract: The invention provides a technique that saves rate conversion accompanying complicated calculations and shares an analog filter for anti-aliasing in a sampling device. The sampling device employs an anti-alias filter having a fixed cutoff frequency, an A/D converter and a D/A converter each having a clock signal input, which are capable of varying a sampling frequency, and a PLL circuit capable of varying the frequency of a clock signal; and it sets the sampling frequency not lower than an integral multiple of a signal bandwidth and double the cutoff frequency for sampling.
    Type: Grant
    Filed: January 3, 2005
    Date of Patent: July 22, 2008
    Assignee: Hitachi, Ltd.
    Inventors: Hirotake Ishii, Katsuhiko Tsunehara, Takashi Yano
  • Publication number: 20080170555
    Abstract: An uplink channel transmission power control method is provided for a CDMA mobile communication system performing one way communication. A base station measures the received level of data transmitted from each mobile terminal at each channel, and generates a transmission power control signal of each uplink traffic channel. The generated transmission power control signals are multiplexed, and the multiplexed common transmission power control signal is transmitted to all mobile terminals by using the common channel shared by the mobile terminals. Each mobile terminal derives the transmission power control signal of the uplink traffic channel used by the terminal, from the received common transmission power control signal, and controls the transmission power of a data packet.
    Type: Application
    Filed: March 14, 2008
    Publication date: July 17, 2008
    Inventors: Katsuhiko Tsunehara, Takashi Yano, Nobukazu Doi, Takaki Uta, Keiji Hasegawa
  • Patent number: 7353032
    Abstract: A method, system, and apparatus are provided for detecting a position of a terminal in a network accurately without a GPS receiver. In one example, a method for locating a position of a terminal includes calculating a position of a base station; detecting a clock time difference between the base station and another base station; measuring a reception timing of a signal received by the base station from the terminal; and locating the position of the terminal using at least the position of the base station, the clock time difference, and the reception timing.
    Type: Grant
    Filed: December 4, 2006
    Date of Patent: April 1, 2008
    Assignee: Hitachi, Ltd.
    Inventors: Atsushi Ogino, Takashi Yano, Katsuhiko Tsunehara, Ryota Yamasaki, Masaaki Shida, Hideya Suzuki, Nobukazu Doi
  • Publication number: 20080068254
    Abstract: By using the delay profile created by delay profile creating section 102 and the first threshold value 330 received from the first threshold value calculation 105, the first threshold value timing detection section 103 selects only the earliest receive timing exceeding the first threshold value, from all the timing that the correlation value in the delay profile becomes a maximum. By using the receive timing and the second threshold value 331 received from the second threshold value calculation section 107, reference timing calculation section 106 selects the reference timing required for calculating the receive timing for the incoming wave of the minimum propagation delay time. The timing delayed by previously set timing behind said reference timing is sent from receive timing calculation section 108 as the receive timing 113 of the incoming wave of the minimum propagation delay time.
    Type: Application
    Filed: October 30, 2007
    Publication date: March 20, 2008
    Inventors: Katsuhiko Tsunehara, Nobukazu Doi, Mikio Kuwahara, Tomoaki Ishifuji
  • Patent number: 7346330
    Abstract: To simplify the configuration of functional modules in a software-defined radio apparatus, and facilitate the development of software. The functional modules have input and output terminals of a common configuration. Distributed timing control is performed so that the functional modules operate in their respective timings, and the functional modules have common input/output signals.
    Type: Grant
    Filed: September 6, 2005
    Date of Patent: March 18, 2008
    Assignee: Hitachi, Ltd.
    Inventors: Manabu Kawabe, Katsuhiko Tsunehara, Hirotake Ishii, Takashi Ishikawa
  • Publication number: 20080045261
    Abstract: An uplink channel transmission power control method is provided for a CDMA mobile communication system performing one way communication. A base station measures the received level of data transmitted from each mobile terminal at each channel, and generates a transmission power control signal of each uplink traffic channel. The generated transmission power control signals are multiplexed, and the multiplexed common transmission power control signal is transmitted to all mobile terminals by using the common channel shared by the mobile terminals. Each mobile terminal derives the transmission power control signal of the uplink traffic channel used by the terminal, from the received common transmission power control signal, and controls the transmission power of a data packet.
    Type: Application
    Filed: October 15, 2007
    Publication date: February 21, 2008
    Inventors: Katsuhiko Tsunehara, Takashi Yano, Nobukazu Doi, Takaki Uta, Keiji Hasegawa
  • Publication number: 20070275725
    Abstract: A method of determining whether or not the terminal handover is executed in accordance with the communication capability available between the wireless communication terminals, wherein the communication capability is measured when each handover request is generated, when one wireless communication system currently in use is changed to another, and regularly at predetermined intervals; a terminal to be used is selected depending on the measured communication capability; and decision is made on whether or not the terminal handover is executed, depending on the result of selection.
    Type: Application
    Filed: May 23, 2007
    Publication date: November 29, 2007
    Inventor: Katsuhiko Tsunehara
  • Patent number: 7280521
    Abstract: In an access point apparatus for a wireless LAN system equipped with a terminal location detecting function, memory capacity required for the access point apparatus is reduced. A received signal memory control module controls access such that a memory space of a received signal memory can be reused by performing sequentially overwrite operation while stopping capturing of the received signal in response to a packet detection signal outputted from a packet detecting module.
    Type: Grant
    Filed: March 2, 2004
    Date of Patent: October 9, 2007
    Assignee: Hitachi, Ltd.
    Inventors: Katsuhiko Tsunehara, Takashi Yano
  • Patent number: 7272418
    Abstract: The present invention reduces the number of base stations required to carry out terminal position detection. A base station which serves for terminal position detection using radio signals comprises an antenna to transmit and receive a radio signal; a radio signal receiver which generates a received signal from the radio signal received; a signal processing unit which processes the received signal and generates a transmit signal; a radio signal transmitter which generates a radio signal from the transmit signal; a control unit which exerts control of the base station operation; and a signal processing unit for position detection which performs signal processing for terminal position detection. A signal receivable range with which a signal can be received by the radio signal receiver is made longer than a signal transmission range with which a signal is transmitted by the radio signal transmitter.
    Type: Grant
    Filed: May 19, 2004
    Date of Patent: September 18, 2007
    Assignee: Hitachi, Ltd.
    Inventors: Katsuhiko Tsunehara, Takashi Yano
  • Patent number: 7266098
    Abstract: A method and system for detecting the position of a mobile unit efficiently and with high precision in a multipath environment. A wireless position detection system made up of a mobile station containing a wireless communication means to allow sending and receiving multiple to and from mutually different antenna positions and, a base station for performing wireless communication with mobile stations containing a wireless communication means and, multiple wireless receivers for receiving each of the multiple signals sent by the wireless communication means between the base stations and, a server for detecting the position of the mobile station from each wireless receiver and from the position of the base station, and the time relating to received signals measured by the multiple wireless receivers.
    Type: Grant
    Filed: October 4, 2004
    Date of Patent: September 4, 2007
    Assignee: Hitachi, Ltd.
    Inventors: Atsushi Ogino, Ryota Yamasaki, Katsuhiko Tsunehara, Naoto Matsuzawa, Hideya Suzuki, Takashi Yano
  • Patent number: 7236879
    Abstract: In the present invention, even if a mobile terminal is close to a base station, the position of the mobile terminal is measured accurately. The disclosed method for calculating the position of a mobile terminal comprises: measuring the differences between the propagation distances of the signals on the channels between a plurality of base stations and the mobile terminal; determining if the mobile terminal is close to a base station; calculating the position of the mobile terminal by a common formula if it is determined that the mobile terminal is not in close proximity to any of the base stations; calculating the position of the mobile terminal in close proximity to a base station if it is determined that the mobile terminal is in close proximity to one of the base stations; and outputting the position of the mobile terminal calculated through either of the routines for calculating the mobile terminal position.
    Type: Grant
    Filed: January 14, 2004
    Date of Patent: June 26, 2007
    Assignee: Hitachi, Ltd.
    Inventors: Katsuhiko Tsunehara, Kenzaburo Fujishima
  • Publication number: 20070087760
    Abstract: A method, system, and apparatus are provided for detecting a position of a terminal in a network accurately without a GPS receiver. In one example, a method for locating a position of a terminal includes calculating a position of a base station; detecting a clock time difference between the base station and another base station; measuring a reception timing of a signal received by the base station from the terminal; and locating the position of the terminal using at least the position of the base station, the clock time difference, and the reception timing.
    Type: Application
    Filed: December 4, 2006
    Publication date: April 19, 2007
    Inventors: Atsushi Ogino, Takashi Yano, Katsuhiko Tsunehara, Ryota Yamasaki, Masaaki Shida, Hideya Suzuki, Nobukazu Doi
  • Patent number: 7167712
    Abstract: A method, system, and apparatus are provided for detecting a position of a terminal in a network accurately without a GPS receiver. In one example, a method for locating a position of a terminal includes calculating a position of a base station; detecting a clock time difference between the base station and another base station; measuring a reception timing of a signal received by the base station from the terminal; and locating the position of the terminal using at least the position of the base station, the clock time difference, and the reception timing.
    Type: Grant
    Filed: June 18, 2003
    Date of Patent: January 23, 2007
    Assignee: Hitachi, Ltd.
    Inventors: Atsushi Ogino, Takashi Yano, Katsuhiko Tsunehara, Ryota Yamasaki, Masaaki Shida, Hideya Suzuki, Nobukazu Doi
  • Patent number: 7116992
    Abstract: When a person of holding a mobile station gets near to a previously set target position, application 200 is started and service of utilizing positional information is provided to the person of holding the mobile station or a third party. The mobile station includes a position comparator 103 for comparing a current position of the mobile station calculated by a position calculator 102 by using a signal from an antenna 100 with a target position inputted from means for target position input 104 and an application controller 106 for controlling the application 200 by using a result of position comparison 120. Further, a frequency of position calculation is pertinently controlled in the position calculator 102 by a position calculation controller 107 operated by the result of position comparison 120.
    Type: Grant
    Filed: April 5, 2000
    Date of Patent: October 3, 2006
    Assignee: Hitachi, Ltd.
    Inventors: Katsuhiko Tsunehara, Mikio Kuwahara, Ayumu Koide, Nobukazu Doi
  • Publication number: 20060199550
    Abstract: A radio communication apparatus having a radio modem for processing a signal in a radio frequency band, a signal processor for processing a base band of a transmission or reception signal, and a CPU for processing a protocol. The signal processor includes signal processing blocks implemented by programmable software. Each of the signal processing blocks processes a signal of reception signal data input from the radio modem or from a preceding stage of one of the signal processing blocks or a signal of transmission signal data input from the CPU or from the preceding stage of signal processing block on the basis of a control signal input together with the transmission signal data or the reception signal data. The control signal can include information required by all the signal processing blocks in a common format.
    Type: Application
    Filed: February 8, 2006
    Publication date: September 7, 2006
    Inventors: Takashi Ishikawa, Manabu Kawabe, Katsuhiko Tsunehara, Hirotake Ishii
  • Patent number: 7072673
    Abstract: A radio handset includes: a signal receiver for receiving signals from a plurality of radio stations; a reception timing analyzer for analyzing reception timings of signals received by the signal reception means; a radio station selector for selecting radio stations to be used in a position calculation; and a position calculator for calculating a position of a signal reception point by using the reception timings of the signals from the selected radio stations. The radio station selector selects the radio stations to be used in the position calculation in such a manner that when reception timings of signals from two or more of the radio stations cannot be separated from one another, it is decided to exclude a signal from at least one of these radio stations.
    Type: Grant
    Filed: October 22, 2002
    Date of Patent: July 4, 2006
    Assignee: Hitachi, Ltd.
    Inventors: Katsuhiko Tsunehara, Kenzaburo Fujishima, Mikio Kuwahara, Koji Watanabe