Patents by Inventor Nobuhiko Miki

Nobuhiko Miki 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: 9173113
    Abstract: A mobile communication terminal includes an interference rejection combining processor for obtaining a received signal vector with regard to each of multiple resource elements and for calculating receiving weights so as to suppress influence to a desired beam of electric wave sent from the desired base station by other beams, on the basis of the received signal vectors; a non-interference-rejection receiving weight calculator for calculating receiving weights so as not to suppress influence to the desired beam by other beams; a signal separator for separating a signal destined for the mobile communication terminal from signals destined for other mobile communication terminals; and an interference rejection combining determiner for determining whether the receiving weights to suppress influence by other beams or the receiving weights calculated by the non-interference-rejection receiving weight calculator should be used for signal separation by the signal separator, on the basis of an index representing a rela
    Type: Grant
    Filed: April 19, 2012
    Date of Patent: October 27, 2015
    Assignee: NTT DOCOMO, INC.
    Inventors: Yusuke Ohwatari, Nobuhiko Miki, Takahiro Asai, Yukihiko Okumura
  • Patent number: 9173123
    Abstract: The present invention provides a base station apparatus, a mobile terminal apparatus and a communication control method which can improve the accuracy of channel quality estimation. A communication control method includes the steps of: arranging a CSI-RS, which is a reference signal for downlink channel estimation, in resources of subframes for CSI-RS transmission; setting, in the subframes for CSI-RS transmission, resources to which the CSI-RS is allocated in neighboring areas, to be muting resources; and reporting transmission interval information, which indicates a transmission interval of subframes that are set at the same timing in a transmission cycle of a subframe for CSI-RS transmission in a subject area and in a transmission cycle of a subframe for CSI-RS transmission in the neighboring areas, to a mobile terminal apparatus.
    Type: Grant
    Filed: October 3, 2011
    Date of Patent: October 27, 2015
    Assignee: NTT DOCOMO, INC.
    Inventors: Nobuhiko Miki, Tetsushi Abe, Yusuke Ohwatari, Satoshi Nagata
  • Publication number: 20150304992
    Abstract: A radio communication system, a radio base station apparatus and a retransmission control method is provided that can realize a highly efficient retransmission control method in a CoMP environment. The retransmission control method is a retransmission control method in a radio communication system which has a first and second radio base station apparatus that carry out coordinated multiple-point transmission with respect to a user terminal, and in which coordinated multiple-point transmission is applicable, and, with this retransmission control method, the first radio base station apparatus and the second radio base station apparatus execute retransmission control for downlink signals received in the user terminal, on a shared basis between the radio base station apparatuses, and one radio base station apparatus of the first radio base station apparatus and the second radio base station apparatus sends a report to the user terminal to the effect that shared retransmission control is executed.
    Type: Application
    Filed: June 18, 2013
    Publication date: October 22, 2015
    Inventors: Satoshi Nagata, Nobuhiko Miki
  • Patent number: 9167448
    Abstract: The present invention provides a mobile terminal apparatus, a base station apparatus, and a communication control method, which allow control suitable for interference reduction in a layered network such as HetNet, and which support a next-generation mobile communication system.
    Type: Grant
    Filed: November 7, 2011
    Date of Patent: October 20, 2015
    Assignee: NTT DOCOMO, INC.
    Inventors: Satoshi Nagata, Tetsushi Abe, Yusuke Ohwatari, Nobuhiko Miki
  • Patent number: 9161367
    Abstract: A user terminal reports a group radio quality of each of radio resource groups to a base station at a first frequence. The base station reports an allocated radio resource group to be allocated for radio communication with the user terminal to the user terminal. The user terminal reports unit radio qualities of radio resource units contained in the allocated radio resource group to the base station at a second frequence that is higher than the first frequence. The base station performs radio resource scheduling on the basis of the unit radio qualities.
    Type: Grant
    Filed: December 6, 2012
    Date of Patent: October 13, 2015
    Assignee: NTT DOCOMO, INC.
    Inventors: Nobuhiko Miki, Moo Ryong Jeong
  • Patent number: 9137803
    Abstract: The present invention provides a radio communication control method, in a communication system in which the system band is widened by aggregating a plurality of fundamental frequency blocks, that is suitable to transmit a downlink shared channel and its downlink control channel in different fundamental frequency blocks. According to this radio communication control method, a normal component carrier and an concatenated component carrier are selected for radio communication with a user terminal, and resources are allocated such that, in the event the user terminal is a terminal of LTE specifications which can support up to a fundamental frequency block, communication is made possible based on the LTE specifications using only the fundamental frequency block, and, in the event the user terminal is a terminal of the LTE-A specifications which can support up to the concatenated frequency block, communication is performed based on the LTE specifications using the concatenated frequency block.
    Type: Grant
    Filed: December 6, 2010
    Date of Patent: September 15, 2015
    Assignee: NTT DOCOMO, INC.
    Inventors: Nobuhiko Miki, Hiroyuki Ishii, Naoto Okubo
  • Patent number: 9136996
    Abstract: A user device for a mobile communication system employing a multicarrier scheme is disclosed. The user device includes a control signal generating unit for generating a control signal. The user device also includes a transmitting unit for transmitting the control signal to a base station. The control signal sent by the user device is mapped to multiple frequency bands throughout a time period of a subframe but separated from each other in a frequency domain. Each of the frequency bands includes subcarriers used in orthogonal frequency division multiplexing.
    Type: Grant
    Filed: June 18, 2009
    Date of Patent: September 15, 2015
    Assignee: NTT DOCOMO, INC.
    Inventors: Teruo Kawamura, Yoshihisa Kishiyama, Nobuhiko Miki, Mamoru Sawahashi
  • Patent number: 9130616
    Abstract: A user apparatus in a multi input multi output (MIMO) mobile communications system using pre-encoding is disclosed. The user apparatus includes a PMI generator which generates a pre-encoding matrix indicator (PMI) which indicates a pre-encoding matrix to be used by a base station; a transmitter which feeds back the PMI to the base station; and a receiver which receives a signal from the base station, wherein the signal received at the receiver includes information on whether it is according to PMI information fed back from the user apparatus after a predetermined elapsed time from a timing at which the PMI information is fed back from the user apparatus.
    Type: Grant
    Filed: December 26, 2008
    Date of Patent: September 8, 2015
    Assignee: NTT DOCOMO, INC.
    Inventors: Hidekazu Taoka, Nobuhiko Miki, Kenichi Higuchi, Mamoru Sawahashi
  • Patent number: 9112696
    Abstract: A radio communication apparatus includes a scheduling unit configured to determine a resource block based on an allocation pattern of resource blocks, where frames in which multiple resource blocks are arranged in a frequency direction are repeatedly formed in a time direction, the allocation pattern using a frame number as a variable. The radio communication apparatus also includes a transmitting unit configured to transmit a packet according to the resource block determined by the scheduling unit.
    Type: Grant
    Filed: September 5, 2012
    Date of Patent: August 18, 2015
    Assignee: NTT DOCOMO, INC.
    Inventors: Nobuhiko Miki, Kenichi Higuchi, Mamoru Sawahashi
  • Publication number: 20150229413
    Abstract: A method to reduce interference between a macro cell and a small cell in a radio communication system in which the macro cell and the small cell are allocated to overlap at least in part is disclosed. The interference reduction method includes the steps in which a small base station transmits macro cell identification information that identifies the macro cell, to a user terminal in a small cell, allocates a downlink control signal for the user terminal to a radio resource unit having a different index number from that of a radio resource unit where a downlink control signal to be transmitted from the macro base station is allocated, and interleaves the downlink control signal for the user terminal using an interleaving pattern that is generated based on the macro cell identification information and that is the same as an interleaving pattern used in macro base station.
    Type: Application
    Filed: July 8, 2013
    Publication date: August 13, 2015
    Applicant: NTT DOCOMO, INC.
    Inventors: Kazuaki Takeda, Satoshi Nagata, Nobuhiko Miki
  • Patent number: 9107111
    Abstract: In order to assure reception of broadcast information by a user terminal handed over to a micro base station by CRE (Cell Range Expansion) and to reduce the number of transmission stopped subframes in a macro base station, the present invention provides a notification method for a user terminal to receive modification notification information for notifying modification in system information from the micro base station, the notification method including: the macro base station notifying the micro base station of a subframe pattern including a protection subframe to protect the modification notification information every a plurality of radio frames; and the micro base station notifying the user terminal of identification information of the protection subframe in the subframe pattern.
    Type: Grant
    Filed: November 8, 2011
    Date of Patent: August 11, 2015
    Assignee: NTT DOCOMO, INC.
    Inventors: Tetsushi Abe, Mikio Iwamura, Hideaki Takahashi, Hiroyuki Ishii, Satoshi Nagata, Naoto Ookubo, Nobuhiko Miki, Anil Umesh
  • Patent number: 9100952
    Abstract: The present invention is directed to preventing occurrence of PDCCH blocking while reducing PDCCH detection errors. The present invention provides a search space size adaptive control section (203) that controls the size of the UE-specific search space adaptively depending on the number of component carriers to which a PDSCH for a mobile station apparatus (10) is assigned, a control information generation section (201) that generates control information reflecting a control result by the search space size adaptive control section (203), and a transmission/reception section (23) that transmits this control information to a mobile station apparatus (10) by RRC signaling.
    Type: Grant
    Filed: December 6, 2010
    Date of Patent: August 4, 2015
    Assignee: NTT DOCOMO, INC.
    Inventor: Nobuhiko Miki
  • Patent number: 9088985
    Abstract: A base station includes a receiving unit configured to receive a UE capability regarding a bandwidth from a mobile station; and a specifying unit configured to specify, among plural basic frequency blocks included in a system band, one or more basic frequency blocks to be used by the mobile station based on the UE capability.
    Type: Grant
    Filed: March 27, 2009
    Date of Patent: July 21, 2015
    Assignee: NTT DOCOMO, INC.
    Inventors: Yoshihisa Kishiyama, Motohiro Tanno, Nobuhiko Miki, Hidekazu Taoka, Kenichi Higuchi, Mamoru Sawahashi
  • Patent number: 9077532
    Abstract: To maintain communications of uplink ACK/NACK signals even for a transition period during which the number of aggregated component carriers is added/removed by higher layer signaling, it is a feature providing a reception section that receives the PDSCH for each of CCs that constitute the system band, a demodulation section (406) that demodulates the received PDSCH of each of CCs, an ACK/NACK signal generating section (418) that generates an uplink ACK/NACK signal in response to a demodulation result of the PDSCH in the demodulation section (406), and a mapping section (415) that allocates radio resources to an uplink ACK/NACK signal of the anchor block using LTE, while allocating user-specific radio resources to uplink ACK/NACK signals of the other CCs.
    Type: Grant
    Filed: April 5, 2011
    Date of Patent: July 7, 2015
    Assignee: NTT DOCOMO, INC.
    Inventors: Nobuhiko Miki, Kazuaki Takeda
  • Patent number: 9071404
    Abstract: To reduce interference that a user terminal connecting to a base station apparatus forming a large-scale cell undergoes from a base station apparatus forming a small-scale cell in a radio communication system in which the small-scale cell is provided in the large-scale cell, a femto-base station forming a femto-cell provided in a macro-cell receives cell identification information of a macro-base station, determines cell identification information of the femto-base station based on the received cell identification information of the macro-base station so as to reduce interference to a control format indicator channel assigned to radio resources by the macro-base station, and controls assignment of control channels to radio resources based on the determined cell identification information of the femto-base station.
    Type: Grant
    Filed: February 17, 2012
    Date of Patent: June 30, 2015
    Assignee: NTT DOCOMO, INC.
    Inventors: Zubin Bharucha, Auer Gunther, Tetsushi Abe, Nobuhiko Miki
  • Patent number: 9066358
    Abstract: A mobile communication terminal including multiple receiving antennas demodulates an interfering UE-specific reference signal that might be used in another mobile communication terminal, and analyzes interference parameters specified by the interfering UE-specific reference signal demodulated by the interfering UE-specific reference signal demodulator, the interference parameters being parameters with regard to another beam sent to another mobile communication terminal from an interfering base station. Then, the mobile communication terminal calculates receiving weights so as to suppress influence to the desired beam from other beams, on the basis of desired beam parameters and the interference parameters.
    Type: Grant
    Filed: April 19, 2012
    Date of Patent: June 23, 2015
    Assignee: NTT DOCOMO, INC.
    Inventors: Yusuke Ohwatari, Nobuhiko Miki, Takahiro Asai, Yukihiko Okumura
  • Publication number: 20150124720
    Abstract: A radio base station communicates with mobile terminals and is configured to be able to execute radio transmission to the mobile terminals using resources that are the same as resources used by a second radio base station forming a second cell having a smaller area within a first cell formed by the radio base station itself and is configured to collaborate with the second radio base station for inter-cell interference control. The radio base station sets a modulation system having a modulation level that is less than that of the modulation system provisionally determined as the modulation system for mobile terminals to which a resource group having a low transmission power is assigned and adjusts transmission parameters in a case in which the modulation system provisionally determined for the mobile terminals to which the resource group having the low transmission power is assigned, is inappropriate for the low transmission power.
    Type: Application
    Filed: March 26, 2013
    Publication date: May 7, 2015
    Applicant: NTT DOCOMO, INC.
    Inventors: Akihito Morimoto, Nobuhiko Miki
  • Publication number: 20150126237
    Abstract: The present invention is designed to report transmit power information of each subframe adequately when a plurality of transmit power are set in a plurality of subframes constituting radio frames.
    Type: Application
    Filed: March 11, 2013
    Publication date: May 7, 2015
    Inventors: Satoshi Nagata, Nobuhiko Miki, Mingju Li, Liu Liu, Lan Chen
  • Publication number: 20150117341
    Abstract: Resources available for large power base stations are controlled in a radio communication system in which mobile terminals with and without interference suppression capability are used together and in which a large power base station and small power base stations coordinate inter-cell interference control. A radio base station coordinates inter-cell interference control with at least one second radio base station forming a second cell within a first cell of the radio base station, the second cell having a smaller area than the first cell. The radio base station has a resource setter for setting a ratio of a first resource in which the radio base station is to execute radio communication and a second resource in which the radio base station is to stop radio communication according to the ratio of the number of mobile terminals capable of executing interference rejection combining to the total number of mobile terminals connecting to the radio base station or to at least one second radio base station.
    Type: Application
    Filed: March 12, 2013
    Publication date: April 30, 2015
    Applicant: NTT DOCOMO, INC.
    Inventors: Yusuke Ohwatari, Nobuhiko Miki, Akihito Morimoto, Yukihiko Okumura
  • Publication number: 20150119053
    Abstract: A high-power radio base station includes a resource setter configured to determine a ratio of the number of second resources at which the radio communicator should stop radio transmission to the sum of the number of the second resources and the number of first resources at which the radio communicator should execute radio transmission. The resource setter determines the ratio on the basis of a first number and a second number, the first number being the number of mobile terminals that are assumed to be connected with the radio base station, rather than the low-power radio base station, when cell range expansion (CRE) is not applied, but are connected with the low-power radio base station by virtue of application of cell range expansion, the second number being the number of mobile terminals connected with the radio base station when cell range expansion is applied.
    Type: Application
    Filed: March 26, 2013
    Publication date: April 30, 2015
    Applicant: NTT DOCOMO, INC.
    Inventors: Akihito Morimoto, Masashige Shirakabe, Nobuhiko Miki, Yukihiko Okumura