Patents by Inventor Kazuo Kawabata

Kazuo Kawabata 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: 8270989
    Abstract: According to priorities determined on the basis of a number of pieces of battery information which concern batteries of a number of communication terminals and each of which is received from the communication terminals, data communication with communication terminals are controlled. The priorities are varied, irrespective of a variation in the pieces of battery information, according to a rule predetermined.
    Type: Grant
    Filed: June 4, 2009
    Date of Patent: September 18, 2012
    Assignee: Fujitsu Limited
    Inventors: Kotaro Shiizaki, Takao Nakagawa, Kazuo Kawabata, Hiroyuki Seki
  • Patent number: 8265647
    Abstract: The present invention enables assignment to a terminal a sub-band having satisfactory communication quality. A reference-signal reception unit receives from a terminal a reference signal spreading over sub-bands. A communication-quality measurement unit measures the communication quality of each of the sub-bands on the basis of the reference signal. A sub-band assignment unit assigns one of the sub-bands to the terminal on the basis of the communication quality, for the terminal to perform wireless communication with the communication device. A reference-signal transmission unit transmits to the communication device a reference signal spreading over the sub-bands. A sub-band-assignment-information reception unit receives information on one of the sub-bands which is assigned to the terminal by the communication device on the basis of the reference signal. A data transmission unit transmits data to the communication device through the sub-band assigned to the terminal.
    Type: Grant
    Filed: September 19, 2008
    Date of Patent: September 11, 2012
    Assignee: Fujitsu Limited
    Inventors: Yoshihiro Kawasaki, Kazuo Kawabata, Yoshiharu Tajima, Hideto Furukawa, Kazuhisa Obuchi
  • Patent number: 8260300
    Abstract: Disclosed is a handover method in radio communication. A base station apparatus monitors the receiving state of a terminal, detects, based upon the receiving state, whether the terminal is one in which there is a possibility that loss of a call or a decline in quality will occur or one in which loss of a call or a decline in quality has occurred, and hands over the terminal to another base station apparatus having a carrier frequency different from that of the present base station apparatus.
    Type: Grant
    Filed: August 31, 2009
    Date of Patent: September 4, 2012
    Assignee: Fujitsu Limited
    Inventors: Takayoshi Ode, Kazuo Kawabata
  • Patent number: 8259685
    Abstract: A first wireless base station providing a first wireless zone encodes a first signal to be transmitted to the first wireless zone at a first coding rate, and transmits the signal at a first transmitting power to the first wireless zone. A second wireless base station belonging to the first wireless zone and providing a second radio zone encodes a second signal common with the first signal at a second coding rate, and transmits the signal at a second transmitting power to the second wireless zone.
    Type: Grant
    Filed: November 17, 2008
    Date of Patent: September 4, 2012
    Assignee: Fujitsu Limited
    Inventor: Kazuo Kawabata
  • Patent number: 8189531
    Abstract: A wireless communication system is disclosed that includes plural wireless base stations that act as an origin wireless base station and a destination wireless base station, and a wireless mobile station. The origin wireless base station starts a handover process in response to movement of the wireless mobile station, attaches a header including transfer order information to transmission packet data addressed to the wireless mobile station, and transfers the transmission packet data with the header to the destination wireless base station. The destination wireless base station receives the transmission packet data with the header, determines whether a transfer order of the transmission packet data is correct based on the transfer order information included in the header, deletes the header from the transmission packet data upon determining that the transfer order is correct, and transmits the transmission packet data without the header to the wireless mobile station upon completion of the handover process.
    Type: Grant
    Filed: April 25, 2007
    Date of Patent: May 29, 2012
    Assignee: Fujitsu Limited
    Inventors: Teruyoshi Watanabe, Kazuo Kawabata
  • Patent number: 8175114
    Abstract: In a base station apparatus, signal processing units are connected to a corresponding antenna unit and another antenna unit, a part of resources for processing a signal received by the antenna unit corresponding to each signal processing unit is allocated to processing of a signal received by the other antenna unit, and the signals received by the corresponding antenna unit and the other antenna unit are subjected to multi-antenna reception processing using the resources.
    Type: Grant
    Filed: January 23, 2009
    Date of Patent: May 8, 2012
    Assignee: Fujitsu Limited
    Inventors: Kotaro Shiizaki, Kazuo Kawabata, Hiroyuki Seki
  • Publication number: 20120108289
    Abstract: A radio communication apparatus that includes a receiver that accomplishes intermittent reception of information in a first mode, the information indicating a transmitting format used for a shared channel via which data is received and a transmitter that accomplishes intermittent transmission of quality information at a timing in the first mode, the quality information relating to the transmitting format; and a controller that sets in advance the timing of the intermittent transmission so as to become a given time before a timing of the intermittent reception.
    Type: Application
    Filed: January 10, 2012
    Publication date: May 3, 2012
    Applicant: FUJITSU LIMITED
    Inventors: Kazuhisa OBUCHI, Hideto FURUKAWA, Kazuo KAWABATA, Yoshiharu TAJIMA
  • Patent number: 8170622
    Abstract: The mobile communication network system having a plurality of mobile communication systems each including a base station performing wireless communications with a mobile station, comprises a storage unit storing location information of the mobile station, an acquisition unit acquiring, when receiving a location registering request from the mobile station, a communication-enabled mobile communication system in the mobile station as a sender of the location registering request, a specifying unit specifying a base station existing within the acquired communication-enabled mobile communication system and existing in the periphery of the base station receiving the location registering request, and a control unit storing the storage unit with information of the base station receiving the location registering request and information of the specified base station as location information about the sender mobile station of the location registering request.
    Type: Grant
    Filed: June 27, 2011
    Date of Patent: May 1, 2012
    Assignee: Fujitsu Limited
    Inventors: Yoshiharu Tajima, Hideto Furukawa, Kazuo Kawabata, Yoshihiro Kawasaki, Kazuhisa Obuchi
  • Publication number: 20120087433
    Abstract: A communications apparatus accommodated in a communications system for exchange of information between a communications apparatuses by a multicarrier transmission mode using a plurality of subcarriers. The communications apparatus includes a dedicated transmission data generator for each communications apparatus, configured to generate frequency band information indicating which frequency band is to be used for transmission of data information between each communications apparatus; and a transmitter configured to transmit the dedicated frequency band information with dedicated control channel for each communications apparatus by using a specific frequency band which is set from among a plurality of frequency bands assigned to the communications system, in which the specific frequency band is set as a primary band in a frequency band assigned to the communication system.
    Type: Application
    Filed: December 2, 2011
    Publication date: April 12, 2012
    Applicant: FUJITSU LIMITED
    Inventors: Takayoshi ODE, Yoshihiro Kawasaki, Kazuo Kawabata
  • Publication number: 20120002585
    Abstract: A technique for improving the efficiency of downloading transmission data is disclosed. An information downloading apparatus downloads differing sets of information to predetermined groups to which a mobile terminal may belong. This apparatus includes a channel selecting unit for selecting from plural information channels an information channel for transmitting transmission data and a transmitting unit for transmitting transmission data using the selected information channel. The channel selecting unit selects an information channel so that sets of transmission data with differing destination addresses may be transmitted through differing information channels. The transmitting unit transmits to each group, through a control channel, information pertaining to whether a set of transmission data exists, the information channel to be used if the set of transmission data exists, and the data length of the set of transmission data. The control channel includes time slots that are associated with the groups.
    Type: Application
    Filed: September 16, 2011
    Publication date: January 5, 2012
    Applicant: FUJITSU LIMITED
    Inventors: Kazuo Kawabata, Yoshiharu Tajima
  • Patent number: 8086256
    Abstract: A scheduling method for transmitting an uplink signal from a mobile station to a base station comprises transmitting the uplink signal in a first scheduling mode in which the mobile station can transmit the uplink data without permission of the base station if an uplink communication state between the base station and the mobile station is higher than or equal to a predetermined quality; and transmitting the uplink signal in a second scheduling mode in which the permission is necessary for the mobile station transmitting the uplink data if the uplink communication state is lower than the predetermined quality.
    Type: Grant
    Filed: August 5, 2009
    Date of Patent: December 27, 2011
    Assignee: Fujitsu Limited
    Inventors: Yoshiharu Tajima, Hideto Furukawa, Kazuo Kawabata, Yoshihiro Kawasaki, Kazuhisa Obuchi
  • Patent number: 8068788
    Abstract: The present method adds uplink data to a transmission request sent to the base station from the mobile station for obtaining permission for data transmission, or to a channel establishment request sent from the mobile station to the base station for establishing a channel in order to send the transmission request therethrough. This makes it possible to suppress delay caused by negotiation prior to actual uplink data transmission as much as possible, thereby realizing efficient uplink data transmission, that is, improved throughput of uplink communication.
    Type: Grant
    Filed: September 15, 2005
    Date of Patent: November 29, 2011
    Assignee: Fujitsu Limited
    Inventors: Yoshiharu Tajima, Hideto Furukawa, Kazuo Kawabata, Yoshihiro Kawasaki, Kazuhisa Obuchi
  • Patent number: 8060022
    Abstract: The present method adds uplink data to a transmission request sent to the base station from the mobile station for obtaining permission for data transmission, or to a channel establishment request sent from the mobile station to the base station for establishing a channel in order to send the transmission request therethrough. This makes it possible to suppress delay caused by negotiation prior to actual uplink data transmission as much as possible, thereby realizing efficient uplink data transmission, that is, improved throughput of uplink communication.
    Type: Grant
    Filed: June 21, 2010
    Date of Patent: November 15, 2011
    Assignee: Fujitsu Limited
    Inventors: Yoshiharu Tajima, Hideto Furukawa, Kazuo Kawabata, Yoshihiro Kawasaki, Kazuhisa Obuchi
  • Patent number: 8054797
    Abstract: A technique for improving the efficiency of downloading transmission data is disclosed. An information downloading apparatus downloads differing sets of information to predetermined groups to which a mobile terminal may belong. This apparatus includes a channel selecting unit for selecting from plural information channels an information channel for transmitting transmission data and a transmitting unit for transmitting transmission data using the selected information channel. The channel selecting unit selects an information channel so that sets of transmission data with differing destination addresses may be transmitted through differing information channels. The transmitting unit transmits to each group, through a control channel, information pertaining to whether a set of transmission data exists, the information channel to be used if the set of transmission data exists, and the data length of the set of transmission data. The control channel includes time slots that are associated with the groups.
    Type: Grant
    Filed: February 9, 2010
    Date of Patent: November 8, 2011
    Assignee: Fujitsu Limited
    Inventors: Kazuo Kawabata, Yoshiharu Tajima
  • Patent number: 8054795
    Abstract: A technique for improving the efficiency of downloading transmission data is disclosed. An information downloading apparatus downloads differing sets of information to predetermined groups to which a mobile terminal may belong. This apparatus includes a channel selecting unit for selecting from plural information channels an information channel for transmitting transmission data and a transmitting unit for transmitting transmission data using the selected information channel. The channel selecting unit selects an information channel so that sets of transmission data with differing destination addresses may be transmitted through differing information channels. The transmitting unit transmits to each group, through a control channel, information pertaining to whether a set of transmission data exists, the information channel to be used if the set of transmission data exists, and the data length of the set of transmission data. The control channel includes time slots that are associated with the groups.
    Type: Grant
    Filed: December 27, 2004
    Date of Patent: November 8, 2011
    Assignee: Fujitsu Limited
    Inventors: Kazuo Kawabata, Yoshiharu Tajima
  • Publication number: 20110255457
    Abstract: The mobile communication network system having a plurality of mobile communication systems each including a base station performing wireless communications with a mobile station, comprises a storage unit storing location information of the mobile station, an acquisition unit acquiring, when receiving a location registering request from the mobile station, a communication-enabled mobile communication system in the mobile station as a sender of the location registering request, a specifying unit specifying a base station existing within the acquired communication-enabled mobile communication system and existing in the periphery of the base station receiving the location registering request, and a control unit storing the storage unit with information of the base station receiving the location registering request and information of the specified base station as location information about the sender mobile station of the location registering request.
    Type: Application
    Filed: June 27, 2011
    Publication date: October 20, 2011
    Inventors: Yoshiharu TAJIMA, Hideto FURUKAWA, Kazuo KAWABATA, Yoshihiro KAWASAKI, Kazuhisa OBUCHI
  • Publication number: 20110200138
    Abstract: A communications apparatus accommodated in a communications system for exchange of information between a communications apparatuses by a multicarrier transmission mode using a plurality of subcarriers. The communications apparatus comprises of a dedicated transmission data generator for each communications apparatus, configured to generate frequency band information indicating which frequency band is to be used for transmission of data information between each communications apparatus and a transmitter configured to transmit the dedicated frequency band information for each communications apparatus by using a specific frequency band which is set from among a plurality of frequency bands assigned to the communications system, in which the specific frequency band is set as a primary band in frequency band assigned to the communication system.
    Type: Application
    Filed: April 25, 2011
    Publication date: August 18, 2011
    Applicant: FUJITSU LIMITED
    Inventors: Takayoshi ODE, Yoshihiro Kawasaki, Kazuo Kawabata
  • Patent number: 7983673
    Abstract: The mobile communication network system having a plurality of mobile communication systems each including a base station performing wireless communications with a mobile station, comprises a storage unit storing location information of the mobile station, an acquisition unit acquiring, when receiving a location registering request from the mobile station, a communication-enabled mobile communication system in the mobile station as a sender of the location registering request, a specifying unit specifying a base station existing within the acquired communication-enabled mobile communication system and existing in the periphery of the base station receiving the location registering request, and a control unit storing the storage unit with information of the base station receiving the location registering request and information of the specified base station as location information about the sender mobile station of the location registering request.
    Type: Grant
    Filed: November 10, 2005
    Date of Patent: July 19, 2011
    Assignee: Fujitsu Limited
    Inventors: Yoshiharu Tajima, Hideto Furukawa, Kazuo Kawabata, Yoshihiro Kawasaki, Kazuhisa Obuchi
  • Publication number: 20110134884
    Abstract: A wireless device transmits first information, representing whether the wireless device expects to receive data from a base station, to the base station before receipt of an inquiry from the base station about whether the wireless device expects to receive the data, and on receipt of the inquiry from the base station, restricts transmission of a response to the inquiry to the base station if the first information is not changed.
    Type: Application
    Filed: February 15, 2011
    Publication date: June 9, 2011
    Applicant: FUJITSU LIMITED
    Inventors: Kotaro Shiizaki, Kazuo Kawabata
  • Patent number: 7953167
    Abstract: A communications system for communications by a multicarrier transmission mode between a plurality of communications apparatuses (10, 20) wherein an overall frequency band assigned to the communications system is divided into a plurality of frequency bands each having a constant bandwidth (for example band 1 to band 4) and a specific band (for example band 1) among these divided bands is used to transmit used frequency band information and thereby determine the assignment of the remaining bands (band 2 to band 4) to be used between said communications apparatuses. Here, the specific band is defined as a main band for transmitting control channel information including said used frequency band information and also data channel information. The main band may also be added with an extension band for transmitting further data channel information. Further, the main band and extension band can be changed in the frequency band used along with time or can be changed in the number thereof.
    Type: Grant
    Filed: April 27, 2007
    Date of Patent: May 31, 2011
    Assignee: Fujitsu Limited
    Inventors: Takayoshi Ode, Yoshihiro Kawasaki, Kazuo Kawabata