Patents by Inventor Takaharu Nakamura

Takaharu Nakamura 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: 20050213643
    Abstract: A system including base stations and a mobile station that performs a three-stage cell search process. Each base station includes a transmission unit using at least one carrier frequency for transmitting a perch channel signal, in which the at least one carrier frequency is uniquely distinguishable from carrier frequencies used by other base stations. The mobile station performs a first-stage search of the three-stage cell search and represents a search of a plurality of carrier frequencies; performs a second-stage search of the three-stage cell search and represents a search of a specified carrier frequency; performs a third-stage search of the three-stage cell search and represents a search of said specified carrier frequency; and includes a controller selecting the highest strength or highest correlation value carrier frequency among the carrier plurality of carrier frequencies based on a result of the first-stage search to set the selected carrier frequency as said specified carrier frequency.
    Type: Application
    Filed: May 19, 2005
    Publication date: September 29, 2005
    Inventors: Hiroaki Iwamoto, Nobuhisa Aoki, Takaharu Nakamura
  • Publication number: 20050213644
    Abstract: A search circuit in a CDMA system which has a plurality of base stations respectively employing different carrier frequencies, the search circuit selects one carrier frequency among the different carrier frequencies to perform a cell search of the one carrier frequency. The search circuit includes a first search unit searching a plurality of carrier frequencies of the DS-CDMA system; and a controller selecting a highest strength or highest correlation value carrier frequency among the plurality of carrier frequencies based on a result of the first search unit, setting the selected carrier frequency as the one carrier frequency among the different carrier frequencies to perform the cell search of the one carrier frequency. A mobile station adopting the search circuit includes a three-stage cell search process.
    Type: Application
    Filed: May 19, 2005
    Publication date: September 29, 2005
    Inventors: Hiroaki Iwamoto, Nobuhisa Aoki, Takaharu Nakamura
  • Publication number: 20050097432
    Abstract: Disclosed are an error-detecting encoding apparatus for creating parity bits by error-detecting encoding processing, appending the parity bits to an input data string and encoding the data string, and an error-detecting decoding apparatus for detecting error using these parity bits. Data segmenting means segments an input data string, which is to undergo error-detecting encoding, into a plurality of sub-data strings, dividing means divides the segmented sub-data strings by a polynomial, which is for generating an error-detecting code, and calculates remainders, converting means applies conversion processing, which conforms to a segmentation position of the sub-data strings, to the remainders on a per-remainder basis, and combining means combines converted values, which have been obtained by the conversion processing, and outputs parity bits. An encoder appends this parity to a data string, and a decoder detects error using this parity.
    Type: Application
    Filed: October 20, 2004
    Publication date: May 5, 2005
    Inventors: Kazuhisa Obuchi, Tetsuya Yano, Takaharu Nakamura
  • Publication number: 20040213145
    Abstract: A spread modulator spreads a signal series. A subcarrier modulator modulates a plurality of subcarriers having different frequencies using the output of the spread modulator. The adder combines modulated subcarriers. A guard interval control unit determines the length of a guard interval depending on the maximum transmission delay difference of the communication link between the transmission device and the reception device. A guard interval insert unit inserts a guard interval into a signal series under the control of a guard interval control unit. A gain adjuster multiplies a transmission signal by a gain coefficient corresponding to the inserted guard interval.
    Type: Application
    Filed: May 26, 2004
    Publication date: October 28, 2004
    Inventor: Takaharu Nakamura
  • Publication number: 20040121769
    Abstract: Disclosed is a mobile radio communication system in which a position registration area number is reported from a base station to a mobile station within a radio zone, position information indicating a position registration area in which a mobile station resides is registered in storage means based upon position registration information that has been transmitted from the mobile station, and when there is an incoming call to a mobile station, a paging call is placed from a plurality of base stations within the position registration area, in which the base station resides, based upon position information that has been read out of the memory means. Updating of the position registration area of a mobile station can be performed automatically on the network side without the mobile station transmitting position registration information to the network side.
    Type: Application
    Filed: December 11, 2003
    Publication date: June 24, 2004
    Inventors: Nobuhisa Aoki, Takaharu Nakamura
  • Patent number: 6714582
    Abstract: In a CDMA transmitting apparatus, a cross-correlation value between different spreading-code sequences used to spread respective ones of a plurality of transmit signals is calculated, an interference interval of a spreading-code sequence is discriminated from the cross-correlation value calculated, and interference noise is reduced by halting transmission of at least one transmit signal, or partially altering at least one spreading-code sequence, with regard to all or part of a spreading-code sequence discriminated to be an interference interval.
    Type: Grant
    Filed: November 27, 2002
    Date of Patent: March 30, 2004
    Assignee: Fujitsu Limited
    Inventors: Takaharu Nakamura, Kazuhisa Obuchi, Nobuhisa Aoki
  • Patent number: 6636549
    Abstract: An n-bit binary value corresponding to an amount of phase shift d is assigned to an SREG, and a shift operation is performed. An n-bit vector value corresponding to a decimal value “1” is assigned to an LAT as an initial value. Thereafter, the input from an SW is sequentially stored. An MUL performs a square operation within a Galois field GF (2n) for the output of the LAT. A DBL performs a double operation within the Galois field GF (2n) for the output of the MUL. The SW selects either of the outputs of the MUL and the DBL according to the output value from the MSB side of the SREG. After the shift operation and the latch operation are performed a number of times n, the n-bit output of the LAT is output as respective phase shift coefficients b0 through bn−1.
    Type: Grant
    Filed: September 16, 1998
    Date of Patent: October 21, 2003
    Assignee: Fujitsu Limited
    Inventors: Takaharu Nakamura, Kazuo Kawabata, Kazuhisa Ohbuchi
  • Publication number: 20030148737
    Abstract: A transmission circuit transmits a connection request including a “signature” to a base station. The demodulator demodulates the AICH for transmitting a notification corresponding to the connection request. When requested communications are enabled, the AICH transmits the “signature”. A multiplier multiplies a demodulation signal by the “signature”. A voltage computation unit converts the output of the multiplier into a voltage value. An integrator integrates the voltage value computed by the voltage computation unit for each received symbol for the respective symbols corresponding to the “signature”. A threshold generation unit adaptively selects one of a threshold determined based on the noise of a transmission path or a threshold determined based on the receiving power. If the output of the integrator is larger than the selected threshold, it is determined that the communications have been enabled.
    Type: Application
    Filed: December 12, 2002
    Publication date: August 7, 2003
    Inventors: Shunji Miyazaki, Takaharu Nakamura
  • Publication number: 20030128740
    Abstract: The signal received by an antenna is input to a receiving circuit. The receiving circuit allows the existence of a perch channel in a particular frequency to be examined by frequency-converting the signal having the frequency corresponding to the frequency specification data within the signal received by the antenna based on the frequency specification data from a controlling circuit. A rectifying circuit rectifies the received signal, and outputs the integrated value of the signal value after being rectified. The integrated value is converted into a digital signal by an A/D converter, and compared with a threshold value by a comparing circuit. If the digital signal value is determined to be larger than the threshold value, a Write signal is output to a storing circuit, so that the frequency specification data output from the controlling circuit is stored in the storing circuit.
    Type: Application
    Filed: January 27, 2003
    Publication date: July 10, 2003
    Inventors: Hiroaki Iwamoto, Nobuhisa Aoki, Takaharu Nakamura
  • Publication number: 20030115531
    Abstract: In an apparatus such as a turbo decoding apparatus in which it is necessary to carry out interleave operation and deinterleave operation, there are provided a memory unit (5) and a memory control unit (12) capable of changing data writing order and data reading order with respect to the memory unit (5) depending on whether data is to be interleaved or deinterleaved. With this arrangement, the single unit of memory (5) can function as an interleaver and a deinterleaver, thereby reducing the size and cost the device.
    Type: Application
    Filed: January 28, 2003
    Publication date: June 19, 2003
    Inventors: Kazuhisa Obuchi, Tetsuya Yano, Kazuo Kawabata, Takaharu Nakamura
  • Publication number: 20030112853
    Abstract: The signal received by an antenna is input to a receiving circuit. The receiving circuit allows the existence of a perch channel in a particular frequency to be examined by frequency-converting the signal having the frequency corresponding to the frequency specification data within the signal received by the antenna based on the frequency specification data from a controlling circuit. A rectifying circuit rectifies the received signal, and outputs the integrated value of the signal value after being rectified. The integrated value is converted into a digital signal by an A/D converter, and compared with a threshold value by a comparing circuit. If the digital signal value is determined to be larger than the threshold value, a Write signal is output to a storing circuit, so that the frequency specification data output from the controlling circuit is stored in the storing circuit.
    Type: Application
    Filed: January 27, 2003
    Publication date: June 19, 2003
    Inventors: Hiroaki Iwamoto, Nobuhisa Aoki, Takaharu Nakamura
  • Patent number: 6574766
    Abstract: In an apparatus such as a turbo decoding apparatus in which it is necessary to carry out interleave operation and deinterleave operation, there are provided a memory unit (5) and a memory control unit (12) capable of changing data writing order and data reading order with respect to the memory unit (5) depending on whether data is to be interleaved or deinterleaved. With this arrangement, the single unit of memory (5) can function as an interleaver and a deinterleaver, thereby reducing the size and cost the device.
    Type: Grant
    Filed: March 30, 2001
    Date of Patent: June 3, 2003
    Assignee: Fujitsu Limited
    Inventors: Kazuhisa Obuchi, Tetsuya Yano, Kazuo Kawabata, Takaharu Nakamura
  • Publication number: 20030081655
    Abstract: In a CDMA transmitting apparatus, a cross-correlation value between different spreading-code sequences used to spread respective ones of a plurality of transmit signals is calculated, an interference interval of a spreading-code sequence is discriminated from the cross-correlation value calculated, and interference noise is reduced by halting transmission of at least one transmit signal, or partially altering at least one spreading-code sequence, with regard to all or part of a spreading-code sequence discriminated to be an interference interval.
    Type: Application
    Filed: November 27, 2002
    Publication date: May 1, 2003
    Inventors: Takaharu Nakamura, Kazuhisa Obuchi, Nobuhisa Aoki
  • Publication number: 20030076877
    Abstract: In a code division multiple access signal receiving apparatus for demodulating transmit data by subjecting a receive signal to despread processing using a code sequence identical with a spreading-code sequence on a transmitting side, a cross-correlation detector calculates a cross-correlation value, on a per-symbol basis, between a spreading-code sequence for spread-spectrum modulating local-station-addressed transmit data and a spreading-code sequence for spread-spectrum modulating other-station-addressed transmit data; a discriminator discriminates whether the calculated cross-correlation value has exceeded a threshold value; and a switch halts input, to a decoder, of a portion of the receive signal that corresponds to the full interval or partial interval of a symbol where the cross-correlation value exceeds the threshold value.
    Type: Application
    Filed: December 4, 2002
    Publication date: April 24, 2003
    Inventor: Takaharu Nakamura
  • Patent number: 6320852
    Abstract: A technique used in a mobile communications system. A mobile terminal station transmits a signal subjected to an error-correction encoding processing. Each of a plurality of base stations receives the signal transmitted from the mobile terminal station via the wireless line, performs an error-correction decoding processing for the received signal, and transmits an error-correction decoded signal to a base-station host apparatus via the wired line. The base-station host apparatus performs an error-correction encoding processing for each of the signals received from the base stations, composes the thus error-correction encoded signals into one signal, and performs an error-correction decoding processing for the composed signal. The technique can improve the error rate of a received signal without increasing the amount of signal data flowing between the base stations and the base-station host apparatus.
    Type: Grant
    Filed: March 2, 1998
    Date of Patent: November 20, 2001
    Assignee: Fujitsu Limited
    Inventors: Kazuhisa Obuchi, Takaharu Nakamura, Kazuo Kawabata, Hiroaki Iwamoto, Yoshiharu Tajima, Kenji Suda, Tetsuya Yano
  • Publication number: 20010014962
    Abstract: In an apparatus such as a turbo decoding apparatus in which it is necessary to carry out interleave operation and deinterleave operation, there are provided a memory unit (5) anda memory control unit (12) capable ofchanging data writing order and data reading order with respect to the memory unit (5) depending on whether data is to be interleaved or deinterleaved. With this arrangement, the single unit of memory (5) can function as an interleaver and a deinterleaver, thereby reducing the size and cost the device.
    Type: Application
    Filed: March 30, 2001
    Publication date: August 16, 2001
    Inventors: Kazuhisa Obuchi, Tetsuya Yano, Kazuo Kawabata, Takaharu Nakamura
  • Patent number: 6275520
    Abstract: A pseudo-noise generating apparatus capable of starting a pseudo-noise sequence from an arbitrary phase using compact processing circuitry. Tap selection patterns corresponding to a plurality of phase shift amounts are stored in advance in a ROM. By giving a phase shift amount to the ROM and setting the corresponding tap selection pattern in AND gates, the pseudo-noise sequence generated by the pseudo-noise generator is shifted in phase, and is loaded into a shift register. After setting a new phase amount in the ROM, the contents of the shift register are transferred into a shift register in the pseudo-noise generator. By repeating this operation, the desired phase shift is accomplished as a sum of a plurality of phase shift amounts.
    Type: Grant
    Filed: November 23, 1998
    Date of Patent: August 14, 2001
    Assignee: Fujitsu Limited
    Inventors: Takaharu Nakamura, Kazuo Kawabata, Kazuhisa Obuchi, Hajime Hamada
  • Patent number: 5654306
    Abstract: A piperdine derivative having the formula (I) or a pharmacologically acceptable salt thereof:R.sup.1 --X--A--R.sup.2 (I)wherein R.sup.1 is selected from the group consisting of substituted or unsubstituted pyrazine, naphthalenedicarboxylic acid imide, bicyclo oct-5-ene-2,3-dicarboxylic acid imide and pyromellitimide;X is --(CH.sub.2).sub.n --, --O(CH.sub.2).sub.n --, --S(CH.sub.2).sub.n --, --NH(CH.sub.2).sub.n --, --SO.sub.1 NH(CH.sub.2).sub.n --, ##STR1## --CH.sub.2 NH(CH.sub.2).sub.n --, a group of the formula ##STR2## wherein n is an integer of 1 through 7 and R.sup.3 is hydrogen, lower alkyl or a benzyl, ##STR3## --O--CH.sub.2 CH.sub.2 CH.dbd. or ##STR4## R.sup.2 is hydrogen, lower alkyl, benzyl, benzyl substituted with hydroxy, methoxy or chlorine, benzoyl, benzyl with a fluorine substituent, pyridyl, 2-hydroxyethyl, pyridylmethyl or ##STR5## wherein Z represents a halogen atom.
    Type: Grant
    Filed: May 5, 1995
    Date of Patent: August 5, 1997
    Assignee: Eisai Co., Ltd.
    Inventors: Hachiro Sugimoto, Takaharu Nakamura, Yutaka Tsuchiya, Hiroyuki Sugumi, Kunizou Higurashi, Norio Karibe, Yoshiharu Yamanishi, Hiroo Ogura, Shin Araki, Atsuhiko Kubota, Michiko Ohtake, Kiyomi Tamatsu
  • Patent number: 5523307
    Abstract: A cyclic amine is defined by the formula: ##STR1## in which A is naphthyl, phenyl, quinolyl or alkyl, X is a group containing carbonyl, n is 2 or 3 and B is alkyl, halogen, phenyl or --YZ, Y being --0--, --CO-- or --NH--, Z being phenyl, naphthyl, pyridyl, alkyl or cycloalkyl. It is useful to treat a mental symptoms associated with a cerebrovascular disease.
    Type: Grant
    Filed: June 7, 1994
    Date of Patent: June 4, 1996
    Assignee: Eisai Co., Ltd.
    Inventors: Hachiro Sugimoto, Takaharu Nakamura, Norio Karibe, Isao Saito, Kunizo Higurashi, Masahiro Yonaga, Takeru Kaneko, Takahiro Nakazawa, Masataka Ueno, Kiyomi Yamatsu, Kohshi Ueno, Masuhiro Ikeda
  • Patent number: 5465950
    Abstract: In a paper sheet conveying and arranging apparatus, a low-friction paper sheet guide member (18) is located in a parallel relationship to a paper sheet advancing direction, and a rotating spiral contact (19) having an axis inclined with respect to a horizontal plane toward an upstream side from the line perpendicular to the paper sheet advancing direction and passing on the upstream side of the paper sheet guide member (18), is rotated with a distal end (19a) frictionally contacting the surface of the paper sheet guide member (18) so as to move the paper sheet downwardly away from the one end of a conveyer. The paper sheet is thereby turned from a horizontal posture to a vertical posture by a minimal turning operation.
    Type: Grant
    Filed: December 20, 1993
    Date of Patent: November 14, 1995
    Assignee: Kabushiki Kaisha Ace Denken
    Inventors: Takatoshi Takemoto, Kazunari Kawashima, Hideyuki Kadomatsu, Moriyuki Aoyama, Takaharu Nakamura