Patents by Inventor Satoshi Tamaki

Satoshi Tamaki 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: 11110942
    Abstract: A railway vehicle stopper includes a first rigid member, a second rigid member, a rubber elastic body, a third rigid member, an abutting member, and a communication passage. The second rigid member is arranged opposed to the truck frame or the vehicle body with an interval. The rubber elastic body elastically couples the supporting portion of the first rigid member to the second rigid member. The third rigid member is mounted inside the supporting portion of the first rigid member to form an air chamber with the second rigid member. The abutting member is coupled to at least one of mutually opposed surfaces of the second rigid member and the third rigid member. The communication passage is provided on one or both of the first rigid member and the third rigid member to communicate the air chamber with an outside.
    Type: Grant
    Filed: February 15, 2019
    Date of Patent: September 7, 2021
    Assignees: SUMITOMO RIKO COMPANY LIMITED, KAWASAKI JUKOGYO KABUSHIKI KAISHA
    Inventors: Motohiro Hatano, Kento Tamaki, Satoshi Ikeda, Kazuo Isomura, Takanori Tojo
  • Publication number: 20210037494
    Abstract: Communication quality such as a delay time is stabilized when a plurality of communication devices on the same mobile object simultaneously perform communication. A wireless communication system that is mounted on a mobile object is a wireless communication system including a first communication device and a second communication device that are mounted on a first mobile object. When information is shared by mobile objects by transmitting packets based on information acquired from a network within the first mobile object to a communication device mounted on a second mobile object, the first communication device and the second communication device transmit packets having the same content by adopting the same communication method and using different channels, and a signal transmission timing from the second communication device is set to be later than a transmission timing from a communication device from the first communication device.
    Type: Application
    Filed: July 30, 2018
    Publication date: February 4, 2021
    Inventor: Satoshi TAMAKI
  • Publication number: 20160057674
    Abstract: The invention is intended to, even in a situation where there are many candidate wireless base stations (WBSs) to which a mobile terminal (MT) may connect, get information of communication conditions between the MT and each of those WBSs and determine an WBS to which the MT should connect in a shorter time. A coverage area of the first WBS is overlapped partially at least by a coverage area of the second WBS. The MT transmits a signal for connection using a predetermined frequency. Upon receiving the signal for connection, the second WBSs each notify the WBS communication manager of their reception results of the signal for connection. The WBS communication manager selects a second WBS to communicate with the MT based on the reception results and notifies the selected second WBS to transmit a response signal to the signal for connection to the MT.
    Type: Application
    Filed: March 15, 2013
    Publication date: February 25, 2016
    Inventors: Eriko TAKEDA, Takashi ISHIKAWA, Satoshi TAMAKI, Go ONO, Katsuhiko TSUNEHARA, Kenzaburo FUJISHIMA
  • Publication number: 20150319754
    Abstract: When a carrier aggregation using a macro cell of a legacy carrier as a primary cell and using a small cell of a new carrier type as a secondary cell is performed, transmission of a control channel (PUCCH) of an uplink is concentrated on an uplink of the macro cell and frequency efficiency is degraded. For this reason, in a state in which the macro cell is configured as the primary cell, a serving cell transmitting the PUCCH is configured to a terminal and the terminal transmits the PUCCH using the configured serving cell.
    Type: Application
    Filed: January 16, 2013
    Publication date: November 5, 2015
    Inventors: Hitoshi ISHIDA, Tomonori YAMAMOTO, Satoshi TAMAKI, Tsuyoshi TAMAKI
  • Patent number: 9161277
    Abstract: Interference applied to neighbor cells during terminal handovers can be reduced in wireless communication systems containing base stations having different cell sizes. A serving cell makes handover judgment criteria easier based on pre-acquired cell size information on its own cell and cell size information of neighbor cells in order to facilitate terminal handovers from a base station with a large cell size to a base station with a small cell size. The serving cell finds evaluation function values based on the propagation state (e.g. reference signal received power) between the terminal and target cell, and the interference and load information exchanged between the base stations, and selects the terminal for handover by comparing the evaluation function value with the handover criteria value. The system selects a target cell having a good effect in lowering interference such as a cell with large reference signal received power acquired from a terminal, to serve as the handover destination.
    Type: Grant
    Filed: February 11, 2011
    Date of Patent: October 13, 2015
    Assignee: HITACHI, LTD.
    Inventors: Tomonori Yamamoto, Satoshi Tamaki, Rintaro Katayama, Hirotake Ishii
  • Patent number: 9137079
    Abstract: A radio communication system using an orthogonal frequency division multiplexing system, including: a baseband unit; and one or plural remote radio units coupled with the baseband unit through an interface; wherein the baseband unit includes a first sample frequency conversion part that performs a first sample frequency conversion processing that down-samples a transmitting signal transmitted through the interface, wherein the remote radio unit includes a second sample frequency conversion part that performs a second sample frequency conversion processing that up-samples a signal received through the interface, and wherein the baseband unit further includes an inverse fast fourier transform part that generates the transmitting signal by an inverse fast fourier transform, and a transmitter characteristic compensation part that conducts frequency characteristic compensation of the first sample frequency conversion processing and the second sample frequency conversion processing for a signal that has not been su
    Type: Grant
    Filed: January 14, 2013
    Date of Patent: September 15, 2015
    Assignee: HITACHI, LTD.
    Inventors: Satoshi Tamaki, Takashi Yano, Koki Uwano
  • Publication number: 20150257160
    Abstract: Even when a downlink radio traffic volume is larger than an uplink radio traffic volume in a radio communication system, but uplink resources are redundant in a related art radio communication system, free uplink resources could not be sufficiently utilized. In a base station having a cellular unit that performs cellular communication with a terminal, and a D2D unit that performs communication with the terminal through a device-to-device communication system, when the downlink radio resources get tight, and the uplink radio resources are redundant, the D2D unit of the base station conducts transmission and reception with the terminal with the use of the uplink radio resources.
    Type: Application
    Filed: January 15, 2015
    Publication date: September 10, 2015
    Inventors: Hitoshi ISHIDA, Tomonori YAMAMOTO, Satoshi TAMAKI, Hirotake ISHII
  • Publication number: 20150189583
    Abstract: The present invention provides a method of controlling the selection of a cell in a radio communication system for increasing the capacity of the system by effectively utilizing a small cell base station and a base station apparatus for realizing it. At least one base station of a macrocell base station and a small cell base station is provided with plural antennas, and the base station selects a cell and adjusts a criterion for reselection by generating processing gain using the plural antennas by signal processing and performing a cell selection bias correcting process using the processing gain using the plural antennas.
    Type: Application
    Filed: November 29, 2012
    Publication date: July 2, 2015
    Inventors: Satoshi Tamaki, Tomonori Yamamoto, Hitoshi Ishida, Eriko Takeda, Go Ono
  • Patent number: 9042348
    Abstract: This invention provides a mobile communication system which expanded the operation limitation of the heretofore adopted mobile communication systems and improved the spectrum efficiency greatly. A data transmission method for use in the mobile communication system of the present invention includes means for channel pluralizing by which to expand the Shannon limit and means for interference reduction by which to expand the interference limit. More specifically, a transmitting module comprises M units of modulators and L units of transmitting antennas, generates L units of signals by multiplying M units of modulated signals by a complex matrix consisting of M×L units of elements, and transmits the L units of signals from the L units of transmitting antennas.
    Type: Grant
    Filed: December 19, 2013
    Date of Patent: May 26, 2015
    Assignee: Hitachi, Ltd.
    Inventors: Takashi Yano, Satoshi Tamaki, Seishi Hanaoka, Takeshi Kato
  • Publication number: 20150087324
    Abstract: A base station is provided with a plurality of radio units that communicate with a terminal, and a control device connected to the plurality of radio units. When there is a large number of terminals positioned at a boundary of the communication areas of a first radio unit and a second radio unit among the plurality of radio units, the control device makes a first cell ID of the first radio unit and a second cell ID of the second radio unit being identical.
    Type: Application
    Filed: August 29, 2014
    Publication date: March 26, 2015
    Inventors: Hitoshi ISHIDA, Tomonori YAMAMOTO, Satoshi TAMAKI, Rintaro KATAYAMA, Eriko TAKEDA, Tsuyoshi TAMAKI
  • Patent number: 8804802
    Abstract: Transmission power relative to a propagation path having a variation in gain is controlled to increase communication channel capacity, and a data rate is controlled in accordance with the variation of the increased communication channel capacity. In order to increase the communication channel capacity, the transmission power is determined so that the sum of noise power (=received noise power/propagation path gain) converted into one at a transmitter and the transmission power becomes constant. As a result, contrary to the background art, the transmission power is controlled to be reduced when the propagation path gain decreases and to be increased when the propagation path gain increases.
    Type: Grant
    Filed: January 28, 2013
    Date of Patent: August 12, 2014
    Assignee: Hitachi, Ltd.
    Inventors: Takashi Yano, Satoshi Tamaki
  • Patent number: 8787146
    Abstract: A discontinuous change in a transmission timing in a time domain, which is caused by a transmission timing adjustment processing of an OFDMA uplink or the like, brings about a discontinuous rotation of a signal phase in a frequency domain, resulting in reduced communication quality. A wireless communication system of the present invention allows the signal phase of the frequency domain in a receiving station to be continuous before and after the timing adjustment processings by controlling a signal sequence in a transmission signal after conversion in the time domain in synchronization with the timing adjustment processing.
    Type: Grant
    Filed: February 16, 2009
    Date of Patent: July 22, 2014
    Assignee: Hitachi, Ltd.
    Inventors: Satoshi Tamaki, Mikio Kuwahara, Kenzaburo Fujishima, Pinai Linwong, Katsuhiko Tsunehara
  • Patent number: 8744362
    Abstract: A cellular radio communication system includes a first mobile terminal, a base station that performs radio communication with first mobile terminals, a second mobile terminal, and a second base station that performs radio communication with second mobile terminals. In the downlink communication, the base station selects a high data rate mode when the radio interference from the base station to the second mobile terminals that are located close to an edge of a communication area of the second base station is small. The base station selects an interference mitigation mode in the downlink communication when the radio interference from the base station to the second mobile terminals that are located close to the edge of the communication area of the second base station is large. Thus, inter-cell interference control can be performed in collaboration with base stations in the radio communication system without having communication interface between the base stations.
    Type: Grant
    Filed: June 2, 2011
    Date of Patent: June 3, 2014
    Assignee: Hitachi, Ltd.
    Inventors: Takuji Kawahatsu, Rintaro Katayama, Satoshi Tamaki, Tomonori Yamamoto
  • Publication number: 20140105323
    Abstract: This invention provides a mobile communication system which expanded the operation limitation of the heretofore adopted mobile communication systems and improved the spectrum efficiency greatly. A data transmission method for use in the mobile communication system of the present invention includes means for channel pluralizing by which to expand the Shannon limit and means for interference reduction by which to expand the interference limit. More specifically, a transmitting module comprises M units of modulators and L units of transmitting antennas, generates L units of signals by multiplying M units of modulated signals by a complex matrix consisting of M×L units of elements, and transmits the L units of signals from the L units of transmitting antennas.
    Type: Application
    Filed: December 19, 2013
    Publication date: April 17, 2014
    Applicant: Hitachi, Ltd.
    Inventors: Takashi Yano, Satoshi Tamaki, Seishi Hanaoka, Takeshi Kato
  • Patent number: 8660049
    Abstract: In a time slot in which a first base station for performing a multicast transmission executes the multicast transmission, a second base station which does not perform the multicast transmission does not perform a unicast data transmission. The time slot in which the first base station performs the multicast transmission is notified to the second base station from a multicast control apparatus for performing scheduling of the multicast transmission to the first base station. Information to receive the multicast transmission is notified from the second base station to a terminal connected to the second base station.
    Type: Grant
    Filed: January 28, 2011
    Date of Patent: February 25, 2014
    Assignee: Hitachi, Ltd.
    Inventors: Rintaro Katayama, Satoshi Tamaki, Tomonori Yamamoto, Hirotake Ishii
  • Publication number: 20140044203
    Abstract: An information transmission method in a multi-carrier wireless communication system in which a transmitter and a receiver conduct communication by using one or plural resource blocks containing plural modulation symbols. One or plural resource blocks correspond to one or plural frequency carriers and one or plural time symbols, including: an operation in which a pilot signal is transmitted by using a part of plural modulation symbols in resource blocks, an operation in which transmission information is encoded by using an error correction code, and an operation in which encoded information is mapped and allocated to modulation symbols, wherein a number of modulation symbols in each resource block in which encoded information is mapped is independent to a number of modulation symbols in resource blocks used to transmit pilot signals, and encoded information mapped and allocated to modulation symbols at the same position as pilot signal is transmitted, are punctured.
    Type: Application
    Filed: July 9, 2013
    Publication date: February 13, 2014
    Applicant: Hitachi, Ltd.
    Inventors: Satoshi TAMAKI, Takashi YANO
  • Patent number: 8630313
    Abstract: Ameliorate deterioration in quality of communication caused by intercell interference with respect to a multicarrier communications protocol, such as OFDM. A method of positioning an error correction-coded signal is changed with a data symbol that is transmitted simultaneously with a pilot signal and a data symbol that is not simultaneous with the pilot symbol. Else, a modulation protocol is changed with a data symbol that is transmitted simultaneously with a pilot signal and a data symbol that is not simultaneous with the pilot symbol. It would further be permissible to lower either a signal amplitude or a power level of a data symbol that is transmitted simultaneously with a pilot signal.
    Type: Grant
    Filed: December 18, 2009
    Date of Patent: January 14, 2014
    Assignee: Hitachi, Ltd.
    Inventors: Satoshi Tamaki, Mikio Kuwahara, Koki Uwano
  • Patent number: 8626243
    Abstract: This invention provides a mobile communication system which expanded the operation limitation of the heretofore adopted mobile communication systems and improved the spectrum efficiency greatly. A data transmission method for use in the mobile communication system of the present invention includes means for channel pluralizing by which to expand the Shannon limit and means for interference reduction by which to expand the interference limit. More specifically, a transmitting module comprises M units of modulators and L units of transmitting antennas, generates L units of signals by multiplying M units of modulated signals by a complex matrix consisting of M×L units of elements, and transmits the L units of signals from the L units of transmitting antennas.
    Type: Grant
    Filed: January 23, 2012
    Date of Patent: January 7, 2014
    Assignee: Hitachi, Ltd.
    Inventors: Takashi Yano, Satoshi Tamaki, Seishi Hanaoka, Takeshi Kato
  • Publication number: 20130301618
    Abstract: Radio communication system and radio station which enable efficient use of radio resources while coping with a sudden change in radio communication quality are to be provided. Radio communication system includes plural radio stations. At least one of the plural radio stations allocates a part of an allocatable communication resource as one or more individual resources in which a source radio station and a destination radio station are individually set, and allocates another part of the allocatable communication resource as one or more shared resources which are used in common by plural source radio stations or plural destination radio stations. Each of the radio stations encodes a transmission signal using a systematic code, sends the transmission signal before being encoded, using the individual resource allocated to each of the radio stations, and sends a parity portion of the encoded transmission signal, using the shared resource allocated.
    Type: Application
    Filed: May 7, 2013
    Publication date: November 14, 2013
    Applicant: Hitachi, Ltd.
    Inventors: Satoshi Tamaki, Yusuke Shomura, Eriko Takeda
  • Patent number: 8560000
    Abstract: A communication device includes pilot signal sending part and transmit power control part and holds a criterion value indicating target channel quality for mobile stations within the area covered by the base station. It creates quality data from reports from one or plural mobile stations, stores the quality data, creates a first representative value indicating average channel quality for the mobile station(s) from the stored quality data, and changes the transmit power depending on the result of comparison between the first representative value and the criterion value. It creates a second representative value indicating distribution of low channel quality from the stored quality data and updates the criterion value depending on the result of comparison between the second representative value and the criterion value.
    Type: Grant
    Filed: January 7, 2011
    Date of Patent: October 15, 2013
    Assignee: Hitachi, Ltd.
    Inventors: Rintaro Katayama, Satoshi Tamaki, Tomonori Yamamoto, Hirotake Ishii, Shigenori Hayase