Patents by Inventor Hiroyuki Atarashi

Hiroyuki Atarashi 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: 9961603
    Abstract: An object is to improve the throughput of a mobile station UE without affecting the coverage of a macrocell in a case where CA is introduced to a HetNet environment. A radio base station eNB according to the present invention is configured to determine whether or not to change the connection destination of a mobile station UE from a small cell #1 to a small cell #2 while the mobile station UE is performing CA by using the macrocell and the small cell #1, based on at least one of the congestion status in each of the small cell #1 and the small cell #2 and the communication quality in each of the small cell #1 and the small cell #2.
    Type: Grant
    Filed: August 28, 2014
    Date of Patent: May 1, 2018
    Assignee: NTT DOCOMO, INC.
    Inventors: Soulisak Ormsub, Wuri Andarmawanti Hapsari, Takahiro Takiguchi, Kengo Yagyu, Hiroyuki Atarashi, Sadayuki Abeta
  • Patent number: 9525528
    Abstract: A transmission apparatus is provided with radio resource assignment means that assigns radio resources to each physical channel according to a type of the physical channel; and transmission means that transmits information to be transmitted by each physical channel using the assigned radio resources.
    Type: Grant
    Filed: October 15, 2014
    Date of Patent: December 20, 2016
    Assignee: NTT DOCOMO, INC.
    Inventors: Nobuhiko Miki, Motohiro Tanno, Kenichi Higuchi, Mamoru Sawahashi, Hiroyuki Atarashi
  • Publication number: 20160212671
    Abstract: An object is to improve the throughput of a mobile station UE without affecting the coverage of a macrocell in a case where CA is introduced to a HetNet environment. A radio base station eNB according to the present invention is configured to determine whether or not to change the connection destination of a mobile station UE from a small cell #1 to a small cell #2 while the mobile station UE is performing CA by using the macrocell and the small cell #1, based on at least one of the congestion status in each of the small cell #1 and the small cell #2 and the communication quality in each of the small cell #1 and the small cell #2.
    Type: Application
    Filed: August 28, 2014
    Publication date: July 21, 2016
    Applicant: NTT DOCOMO, INC.
    Inventors: Soulisak Ormsub, Wuri Andarmawanti Hapsari, Takahiro Takiguchi, Kengo Yagyu, Hiroyuki Atarashi, Sadayuki Abeta
  • Patent number: 9391750
    Abstract: A transmission apparatus is provided with radio resource assignment means that assigns radio resources to each physical channel according to a type of the physical channel; and transmission means that transmits information to be transmitted by each physical channel using the assigned radio resources.
    Type: Grant
    Filed: March 20, 2006
    Date of Patent: July 12, 2016
    Assignee: NTT DOCOMO, INC.
    Inventors: Nobuhiko Miki, Motohiro Tanno, Kenichi Higuchi, Mamoru Sawahashi, Hiroyuki Atarashi
  • Patent number: 9370014
    Abstract: In a radio communication system, a downlink frequency band includes a plurality of frequency blocks including one or more carrier frequencies, and one or more frequency blocks are used for data transmission to a single user. A radio communication apparatus for use in the communication system has an evaluation unit evaluating the quality of a received signal for each frequency block and storing plurality of stored quality evaluations of the received signal, a comparison unit comparing the plural quality evaluations of the received signal, and a transmission unit transmitting a predetermined number of the quality evaluations of the received signal over an uplink control channel.
    Type: Grant
    Filed: May 9, 2013
    Date of Patent: June 14, 2016
    Assignee: NTT DOCOMO, INC.
    Inventors: Motohiro Tanno, Hiroyuki Atarashi, Kenichi Higuchi, Mamoru Sawahashi
  • Patent number: 9185687
    Abstract: In a radio communication system defining a plurality of bandwidths, mobile terminals of kinds respectively corresponding to the plurality of bandwidths are accommodated in the system, and a minimum transmission bandwidth of the plurality of bandwidths is set as a transmission bandwidth of a downlink common channel. Or, every mobile terminal accommodated in the radio communication system is provided with a capability for processing a bandwidth equal to or greater than a predetermined value, and equal to or more than two transmission bandwidths that are equal to or less than a predetermined value are set as a transmission bandwidth of a downlink common channel. In the latter case, the mobile terminal identifies a bandwidth of a received downlink common channel.
    Type: Grant
    Filed: October 31, 2013
    Date of Patent: November 10, 2015
    Assignee: NTT DOCOMO, INC.
    Inventors: Kenichi Higuchi, Hiroyuki Atarashi, Mamoru Sawahashi
  • Patent number: 9144078
    Abstract: In a radio communication system, a downlink frequency band includes a plurality of frequency blocks including one or more carrier frequencies, and one or more frequency blocks are used for data transmission to a single user. A radio communication apparatus for use in the communication system has an evaluation unit evaluating the quality of a received signal for each frequency block and storing plurality of stored quality evaluations of the received signal, a comparison unit comparing the plural quality evaluations of the received signal, and a transmission unit transmitting a predetermined number of the quality evaluations of the received signal over an uplink control channel.
    Type: Grant
    Filed: March 20, 2006
    Date of Patent: September 22, 2015
    Assignee: NTT DOCOMO, INC.
    Inventors: Motohiro Tanno, Hiroyuki Atarashi, Kenichi Higuchi, Mamoru Sawahashi
  • Publication number: 20150063292
    Abstract: A transmission apparatus is provided with radio resource assignment means that assigns radio resources to each physical channel according to a type of the physical channel; and transmission means that transmits information to be transmitted by each physical channel using the assigned radio resources.
    Type: Application
    Filed: October 15, 2014
    Publication date: March 5, 2015
    Applicant: NTT DOCOMO, INC.
    Inventors: Nobuhiko Miki, Motohiro Tanno, Kenichi Higuchi, Mamoru Sawahashi, Hiroyuki Atarashi
  • Patent number: 8971283
    Abstract: A radio resource assignment method for a physical channel in an uplink directed from a mobile apparatus to a base station in a radio communication system, includes: assigning a contention-based channel and a scheduled channel according to one of a time division scheme, a frequency division scheme, and a hybrid scheme of the time division scheme and the frequency division scheme. In addition, radio resources are properly assigned to each of the contention-based channel, a common control channel of the scheduled channel, and a shared data channel of the scheduled channel.
    Type: Grant
    Filed: March 27, 2006
    Date of Patent: March 3, 2015
    Assignee: NTT DOCOMO, INC.
    Inventors: Kenichi Higuchi, Hiroyuki Atarashi, Mamoru Sawahashi
  • Publication number: 20140056264
    Abstract: In a radio communication system defining a plurality of bandwidths, mobile terminals of kinds respectively corresponding to the plurality of bandwidths are accommodated in the system, and a minimum transmission bandwidth of the plurality of bandwidths is set as a transmission bandwidth of a downlink common channel. Or, every mobile terminal accommodated in the radio communication system is provided with a capability for processing a bandwidth equal to or greater than a predetermined value, and equal to or more than two transmission bandwidths that are equal to or less than a predetermined value are set as a transmission bandwidth of a downlink common channel. In the latter case, the mobile terminal identifies a bandwidth of a received downlink common channel.
    Type: Application
    Filed: October 31, 2013
    Publication date: February 27, 2014
    Applicant: NTT DOCOMO, INC.
    Inventors: Kenichi Higuchi, Hiroyuki Atarashi, Mamoru Sawahashi
  • Patent number: 8630244
    Abstract: The present invention is directed to a channel structuring method that includes a step of providing time frames segmented at a predetermined interval in communication channels of n subcarriers, a step of selecting a predetermined number of subcarriers from n subcarriers and a step of inserting a common control channel signal and a common pilot signal periodically into each of the time frames of the selected subcarriers.
    Type: Grant
    Filed: December 2, 2009
    Date of Patent: January 14, 2014
    Assignee: NTT DoCoMo, Inc.
    Inventors: Hiroyuki Atarashi, Sadayuki Abeta, Mamoru Sawahashi
  • Patent number: 8626216
    Abstract: In a radio communication system defining a plurality of bandwidths, mobile terminals of kinds respectively corresponding to the plurality of bandwidths are accommodated in the system, and a minimum transmission bandwidth of the plurality of bandwidths is set as a transmission bandwidth of a downlink common channel. Or, every mobile terminal accommodated in the radio communication system is provided with a capability for processing a bandwidth equal to or greater than a predetermined value, and equal to or more than two transmission bandwidths that are equal to or less than a predetermined value are set as a transmission bandwidth of a downlink common channel. In the latter case, the mobile terminal identifies a bandwidth of a received downlink common channel.
    Type: Grant
    Filed: October 31, 2006
    Date of Patent: January 7, 2014
    Assignee: NTT DoCoMo, Inc.
    Inventors: Kenichi Higuchi, Hiroyuki Atarashi, Mamoru Sawahashi
  • Patent number: 8619920
    Abstract: A transmitter comprises a first spreading unit configured to multiply each of multiple data symbols with a first spreading code sequence of a first spreading factor; a compression and repetition unit configured to compress output signals of the first spreading unit in time domain and repeat the compressed signal L times (where L is a natural number greater than or equal to 2); a phase modulation unit configured to multiply the compressed and repeated signal with a user dependent phase and output a data block consisting of L sub-blocks; a second spreading unit configured to replicate the data block according to a second spreading factor and multiply each set of the replicated sub-blocks with a second spreading code sequence of the second spreading factor to produce a two-dimensionally spread signal; and a wireless transmission unit configured to transmit the two-dimensionally spread signal using a single-carrier transmission scheme.
    Type: Grant
    Filed: November 5, 2008
    Date of Patent: December 31, 2013
    Assignees: NTT DoCoMo, Inc., Agency for Science, Technology and Research
    Inventors: Hiroyuki Atarashi, Mamoru Sawahashi, Francois Po Shin Chin, Zhongding Lei, Xiaoming Peng, Ying-Chang Liang
  • Patent number: 8498663
    Abstract: A base station includes: means that derives a transmission power of a mobile station based on receive quality of an uplink pilot channel; means that reports the derived transmission power to the mobile station; and means that receives a control channel transmitted by the mobile station according to the reported information. Accordingly, irrespective of transmission power history over a past continuous time, the mobile station receives an instruction on the transmission power from the base station each time when transmitting a packet so as to be able to adjust the transmission power.
    Type: Grant
    Filed: September 13, 2012
    Date of Patent: July 30, 2013
    Assignee: NTT DoCoMo, Inc.
    Inventors: Kenichi Higuchi, Hiroyuki Atarashi, Mamoru Sawahashi
  • Patent number: 8477732
    Abstract: An apparatus determines a transmission bandwidth for uplink transmission of a signal and includes a reception unit that receives a predefined signal from a mobile station and derives a channel quality indicator based on the received signal. The apparatus also includes a storage unit that stores a relationship between the channel quality indicator and the transmission bandwidth of the mobile station. The apparatus also includes a determination unit that determines the transmission bandwidth based on the relationship and a transmission unit that transmits the transmission bandwidth to the mobile station.
    Type: Grant
    Filed: October 31, 2006
    Date of Patent: July 2, 2013
    Assignee: NTT DoCoMo, Inc.
    Inventors: Kenichi Higuchi, Hiroyuki Atarashi, Mamoru Sawahashi
  • Patent number: 8477706
    Abstract: A transmission apparatus which attempts improvement of signal quality in an uplink and a downlink carries out radio transmission of different signals simultaneously from respective ones of a plurality of antennas. The apparatus has pilot multiplexing means for multiplexing a pilot channel to transmit from each antenna in one or more of a time division multiplexing method, a frequency division multiplexing method and a code division multiplexing method, data multiplexing means for time-multiplexing a pilot channel and a data channel, and means for transmitting a signal in a least one of a space division multiplexing (SDM) method and a space time transmission diversity (STTD) method.
    Type: Grant
    Filed: May 6, 2011
    Date of Patent: July 2, 2013
    Assignee: NTT DoCoMo, Inc.
    Inventors: Mamoru Sawahashi, Kenichi Higuchi, Hiroyuki Atarashi
  • Patent number: 8400909
    Abstract: A disclosed transmission apparatus comprises a switching portion that switches radio access methods; a frequency domain signal generation portion that allocates a radio resource to a spread chip sequence on which one of a fast Fourier transformation and a series/parallel conversion is performed in accordance with the switched radio accessed method, so as to generate a signal in a frequency domain; and a transmission signal generation portion that performs a fast inverse Fourier transformation on the signal in the frequency domain so as to generate a transmission signal.
    Type: Grant
    Filed: November 17, 2010
    Date of Patent: March 19, 2013
    Assignee: NTT DoCoMo, Inc.
    Inventors: Yoshiaki Ofuji, Hiroyuki Atarashi, Kenichi Higuchi, Mamoru Sawahashi
  • Patent number: 8369380
    Abstract: A transmitter includes: spread code multiplying means that multiplies a symbol indicating a reference signal by spread code to generate a chip sequence after spreading; chip pattern generation means that generates a chip pattern by performing chip repetition a predetermined repetition number of times on the chip sequence after spreading; and multiplying means that multiplies a signal having the chip pattern by a phase specific to the transmitter.
    Type: Grant
    Filed: March 24, 2006
    Date of Patent: February 5, 2013
    Assignee: NTT Docomo, Inc.
    Inventors: Hiroyuki Atarashi, Teruo Kawamura, Yoshikazu Goto, Mamoru Sawahashi
  • Publication number: 20130012256
    Abstract: A base station includes: means that derives a transmission power of a mobile station based on receive quality of an uplink pilot channel; means that reports the derived transmission power to the mobile station; and means that receives a control channel transmitted by the mobile station according to the reported information. Accordingly, irrespective of transmission power history over a past continuous time, the mobile station receives an instruction on the transmission power from the base station each time when transmitting a packet so as to be able to adjust the transmission power.
    Type: Application
    Filed: September 13, 2012
    Publication date: January 10, 2013
    Applicant: NTT DOCOMO, INC.
    Inventors: Kenichi Higuchi, Hiroyuki Atarashi, Mamoru Sawahashi
  • Patent number: 8335267
    Abstract: A mobile station includes a control unit configured to change at least one parameter for a retransmission packet from that of a transmission packet, where the at least one parameter is selected from a data modulation scheme; a channel coding rate; a puncturing pattern; a spreading factor; a frequency bandwidth; a frequency allocation position; and transmission power.
    Type: Grant
    Filed: February 7, 2007
    Date of Patent: December 18, 2012
    Assignee: NTT DoCoMo, Inc.
    Inventors: Hiroyuki Atarashi, Nobuhiko Miki, Kenichi Higuchi, Mamoru Sawahashi