Patents by Inventor Shiro Mazawa

Shiro Mazawa 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: 7907951
    Abstract: Admission control wireless resources including abase station which obtains a down wireless resource available rate based on a down QoS requested bandwidth Bi requested by a terminal i during QoS communication and a data rate Ri which the terminal can receive. A down wireless resource usage rate is obtained by dividing a down QoS requested bandwidth B requested by the terminal trying to perform QoS communication by the data rate R which the terminal can receive. An up wireless resource available rate is obtained based on ROT of an up channel and a threshold value T1 indicating an allowable upper limit of the ROT. The QoS communication is performed on the terminal in which the up and down wireless resource available rates are respectively equal to or more than the up and down wireless resource usage rates.
    Type: Grant
    Filed: October 22, 2009
    Date of Patent: March 15, 2011
    Assignee: Hitachi, Ltd.
    Inventors: Daigo Takayanagi, Kiyoshi Kawamoto, Shiro Mazawa
  • Patent number: 7894817
    Abstract: In a wireless communications system operating according to CDMA or the like, when one terminal simultaneously performs communication using multiple wireless resources (e.g., multiple carriers), there was a problem that when it was attempted to guarantee network mobility by the same soft handoff system as in the case where communication was performed using only one wireless resource, efficiency suffered from the viewpoint of network forwarding load, processing load and wireless resource occupancy time. Soft handoff termination is judged and soft handoff is forcibly terminated according to whether or not the data rate obtained for all resources on the network side satisfies a requested rate, based on a reception state notification from a terminal concerning wireless resources.
    Type: Grant
    Filed: July 3, 2007
    Date of Patent: February 22, 2011
    Assignee: Hitachi, Ltd.
    Inventors: May Takada, Yosuke Takahashi, Shiro Mazawa, Rintaro Katayama
  • Publication number: 20110010592
    Abstract: Information transmitting arrangements for transmitting information through a plurality of base stations from a master station to a plurality of slave stations which communicate with the base stations.
    Type: Application
    Filed: September 17, 2010
    Publication date: January 13, 2011
    Inventors: Daigo Takayanagi, Shiro Mazawa, Yosuke Takahashi, Akihiko Yoshida
  • Publication number: 20100202342
    Abstract: A transmission area is specified flexibly in accordance with the contents of a flow. An area identification number (SHOG) is specified for each interlaced stream of wireless base stations. The same flow is sent at the same timing (or substantially at the same timing) in the interlaced stream specified for the same SHOG. A wireless terminal determines a neighbor sector or a neighbor wireless base station sending the same flow, in accordance with information given from the wireless base stations, and receives and combines the flows.
    Type: Application
    Filed: April 20, 2010
    Publication date: August 12, 2010
    Inventors: Akihiko YOSHIDA, Shiro Mazawa, Yosuke Takahashi, Daigo Takayanagi
  • Publication number: 20100144358
    Abstract: A wireless base station for transmitting and receiving a wireless signal with at least one wireless terminal existing in an area, having a transmitter for transmitting the wireless signal, and a receiver for receiving the wireless signal; a timing management unit for managing the information on start timing of the transmitter and receiver, as well as noticing the information on start timing of the transmitter and receiver to the at least one wireless terminal; and a control unit for performing the switching control of start and stop of the transmitter and receiver.
    Type: Application
    Filed: October 7, 2009
    Publication date: June 10, 2010
    Inventors: Michio IGUCHI, Shiro MAZAWA
  • Patent number: 7729309
    Abstract: A transmission area is specified flexibly in accordance with the contents of a flow. An area identification number (SHOG) is specified for each interlaced stream of wireless base stations. The same flow is sent at the same timing (or substantially at the same timing) in the interlaced stream specified for the same SHOG. A wireless terminal determines a neighbor sector or a neighbor wireless base station sending the same flow, in accordance with information given from the wireless base stations, and receives and combines the flows.
    Type: Grant
    Filed: October 12, 2006
    Date of Patent: June 1, 2010
    Assignee: Hitachi, Ltd.
    Inventors: Akihiko Yoshida, Shiro Mazawa, Yosuke Takahashi, Daigo Takayanagi
  • Patent number: 7724724
    Abstract: In order to realize such communication control as to reliably reconstruct communication information transmitted from a plurality of ANs at a plurality of ATs even when a BCMCS flow is added or deleted, a radio communication system includes a transmitter for transmitting control information necessary for the ATs to receive the communication information from a radio communication system at intervals of a predetermined period, and a controller for controlling to transmit a plurality of pieces of communication information to the ATs at intervals of a constant cycle and in synchronism with a transmission period of the control information.
    Type: Grant
    Filed: November 4, 2004
    Date of Patent: May 25, 2010
    Assignee: Hitachi, Ltd.
    Inventors: Akihiko Yoshida, Shiro Mazawa, Kiyoshi Kawamoto, Yosuke Takahashi, Keiji Usuba
  • Publication number: 20100040013
    Abstract: Admission control wireless resources including abase station which obtains a down wireless resource available rate based on a down QoS requested bandwidth Bi requested by a terminal i during QoS communication and a data rate Ri which the terminal can receive. A down wireless resource usage rate is obtained by dividing a down QoS requested bandwidth B requested by the terminal trying to perform QoS communication by the data rate R which the terminal can receive. An up wireless resource available rate is obtained based on ROT of an up channel and a threshold value T1 indicating an allowable upper limit of the ROT. The QoS communication is performed on the terminal in which the up and down wireless resource available rates are respectively equal to or more than the up and down wireless resource usage rates.
    Type: Application
    Filed: October 22, 2009
    Publication date: February 18, 2010
    Inventors: Daigo TAKAYANAGI, Kiyoshi Kawamoto, Shiro Mazawa
  • Patent number: 7634278
    Abstract: There is provided admission control in view of wireless resources. A base station 120 obtains a down wireless resource available rate (available rate of slot allocation) based on a down QoS requested bandwidth Bi requested by a terminal i during QoS communication and a data rate Ri which the terminal can receive. A down wireless resource usage rate necessary to ensure the requested bandwidth B is obtained by dividing a down QoS requested bandwidth B requested by the terminal trying to perform QoS communication by the data rate R which the terminal can receive. The base station 120 obtains an up wireless resource available rate based on ROT of an up channel and a threshold value T1 indicating an allowable upper limit of the ROT. Besides, an up wireless resource usage rate necessary to ensure an up requested bandwidth requested by the terminal is obtained.
    Type: Grant
    Filed: June 28, 2006
    Date of Patent: December 15, 2009
    Assignee: Hitachi Communication Technologies, Ltd.
    Inventors: Daigo Takayanagi, Kiyoshi Kawamoto, Shiro Mazawa
  • Publication number: 20090296631
    Abstract: An aggregation device performs a synchronous processing so that a synchronous delivery may be made from a plurality of base stations through a broadcasting channel. A BSN (104) gives, when it sends broadcasting data for the synchronous delivery to an AN (102) and an AN (103), a period number and a sequence number are added to the broadcasting data so that the data to be sent from the AN (102) and the AN (103 can be synchronously delivered.
    Type: Application
    Filed: December 19, 2005
    Publication date: December 3, 2009
    Inventors: Yosuke Takahashi, Shiro Mazawa, Akihiko Yoshida, Daigo Takayanagi
  • Publication number: 20090264134
    Abstract: In a radio communication system wherein radio frequencies for communicating with a radio terminal are different in radio base stations, a table in which positional information, information on the frequency used for transmission/reception to/from the terminal, and a decision condition in a handoff operation are stored as to each base station is prepared in a base station controller beforehand. When the positional information is received from the radio terminal, the base station controller selects the base station being a handoff candidate, on the basis of the positional information of the radio terminal, the positional information of each base station and the decision condition of the handoff operation with reference to the table, and it transmits a handoff request message which contains the information on the frequency of the base station being the handoff candidate, to the radio terminal through the base station communicating with the radio terminal.
    Type: Application
    Filed: April 14, 2009
    Publication date: October 22, 2009
    Inventors: Dan Xu, Yuichiro Katsu, Tsutomu Uchida, Shiro Mazawa
  • Publication number: 20090196241
    Abstract: The present invention is to accommodate a large number of users required in a digital radio communication system and to prevent communication quality from deteriorating. The present invention is to prevent the occurrence of a delay by adding a process for restricting packet assignment for a call having low communication quality. When the average DRC value is equal to or smaller than a threshold, assigned slots are thinned out to improve communication quality for radio terminals close to cell boundaries and to increase the number of radio terminals accommodated. As a method for thinning out assigned slots, packets received from an upper level unit of a radio base station are, for example, discarded before transmission as long as the lowest limit sound quality is maintained. With this operation, the lowest limit sound quality is ensured.
    Type: Application
    Filed: December 17, 2008
    Publication date: August 6, 2009
    Inventors: Atsushi Abe, Masanori Taira, Shiro Mazawa, Yosuke Takahashi
  • Publication number: 20090180420
    Abstract: A slave station which transmits/receives signals to/from a master station, the slave station includes: a transmitting unit and receiving unit for transmitting/receiving signals regarding the master station; a storing unit; an input unit; wherein under a control by a control unit, the transmitting unit transmits a transmission request for transmitting multicast data to the master station in accordance with a timing of power-on or an input by the input unit; the receiving unit receives information of a number of times of transmission for requested multicast data from the master station and stores the number in the storing unit; and after receiving the multicast data the number of times of transmission stored in the storing unit, the control unit determines presence of absence of lacking data which have not been received and, transmits a retransmission request for requesting the lacking data in a case of presence the lacking data.
    Type: Application
    Filed: March 26, 2009
    Publication date: July 16, 2009
    Inventors: Daigo TAKAYANAGI, Shiro MAZAWA, Yosuke TAKAHASHI, Akihiko YOSHIDA
  • Publication number: 20090180438
    Abstract: In a case where a switching source wireless communication system is a wireless communication system in which a transmission timing of a packet or data rate can be controlled in a wireless base station, the switching source wireless communication system, which notifies information on a timing when a wireless terminal communicates the switching destination wireless communication system with respect to the switching source wireless communication system in advance, starts time-division communication between switching destination and switching source wireless communication systems, and receives the timing information, controls a transmission timing or a data rate in accordance with the timing information.
    Type: Application
    Filed: December 17, 2008
    Publication date: July 16, 2009
    Inventors: Shiro MAZAWA, Michio IGUCHI, Takanori MORITOMO, Masao HAYAMA
  • Publication number: 20090180419
    Abstract: An information transmitting method including; determining, on a basis of a packet error rate from a master station to slave stations, a number of times of multicast transmission in accordance with an expected value of a number of slave stations that transmit a retransmission request, an expected value of a number of retransmitted packets responding to the retransmission request, or a probability that the slave stations receive all packets forming information; notifying determined number of times of multicast transmission to the slave stations; and transmitting, to plural slave stations in multicast, same information formed of plural packets the determined times of multicast transmission.
    Type: Application
    Filed: March 26, 2009
    Publication date: July 16, 2009
    Inventors: Daigo TAKAYANAGI, Shiro MAZAWA, Yosuke TAKAHASHI, Akihiko YOSHIDA
  • Publication number: 20090135763
    Abstract: The present invention can be achieved by a base station in which a terminal is accommodated and the terminal is communicated with another terminal, and which includes: a data rate operation/management unit which operates and stores a time-averaged data rate Rave of the terminal; a threshold value operation/management unit which obtains a current communication data rate R of the terminal to operate and store R/Rave; and a delay management unit which controls to reduce delay on the basis of the R/Rave.
    Type: Application
    Filed: November 25, 2008
    Publication date: May 28, 2009
    Inventors: Michio Iguchi, Shiro Mazawa, Yosuke Takahashi
  • Publication number: 20090093253
    Abstract: A hand-off control method (FIG. 4) for suppressing reverse radio wave interference between radio access terminals and for accelerating hand-off, in which when a base station of greatest forward reception power has changed from a BTS1 to a BTS2 in a forward link, the radio access terminal (AT) alters the ID of a designated communication-destination base station to the BTS2 in an R-CQICH transmitted cyclically, and it makes a hand-off request after having increased transmission power of the R-CQICH a fixed quantity (403-406). The BTS1 does not transmit an FLAB and data. The BTS2 receives the R-CQICH (406) and succeeds in demodulation, thereby to recognize that the BTS2 has been designated as the communication-destination base station, and it transmits (407) an FLAB after execution and completion of a hand-off process.
    Type: Application
    Filed: July 18, 2008
    Publication date: April 9, 2009
    Inventors: Rumiko HAYASHI, Shiro Mazawa, Toshiyuki Saito
  • Publication number: 20090023382
    Abstract: A radio communication system includes a grouping unit for grouping a plurality of base stations into a plurality of groups (Soft Handoff Groups) and a determining unit for selecting base stations belonging to one and the same group selected from the groups produced by the grouping unit and for determining the base stations as base stations to send communication packets to an access terminal.
    Type: Application
    Filed: September 23, 2008
    Publication date: January 22, 2009
    Applicant: Hitachi Communication Technologies, Ltd.
    Inventors: Akihiko YOSHIDA, Shiro Mazawa, Kiyoshi Kawamoto, Yosuke Takahashi, Keiji Usuba
  • Publication number: 20090016265
    Abstract: A radio communication system of an HARQ method that makes an HARQ transmission interval of subpackets appropriate and reduces data transmission delay resulting from subpacket retransmission. In the radio communication system in which a packet is transmitted and receives with the HARQ method between a base station and multiple radio mobile stations, each of the base station and the multiple radio mobile stations has: a packet transmission circuit for transmitting subpackets in predetermined intervals; a packet reception circuit for repeating decoding processing by combining a newly received subpacket and a previously received former subpacket until an original packet is successfully decoded; and a HARQ control equipped with a function of, for packet communication whose data length is short, transmitting a subpacket or response from the packet transmission circuit in an HARQ transmission interval that is shortened from the HARQ transmission interval of the normal mode.
    Type: Application
    Filed: March 19, 2008
    Publication date: January 15, 2009
    Inventors: Rintaro KATAYAMA, Toshiyuki Saito, Shiro Mazawa, Daigo Takayanagi
  • Publication number: 20090005060
    Abstract: A wireless access terminal, after handoff, adds channel quality information calculated in the wireless access terminal to a header of transmit data and transmits this data until a wireless base station succeeds in receiving at least one or more packets. The wireless base station, when having succeeded in receiving a packet for the first time after the handoff, extracts the channel quality information from a received header to initialize channel quality information inside the wireless base station. Subsequently, the wireless base station autonomously updates the channel quality information in response to success or failure of packet reception and controls the transmission rate.
    Type: Application
    Filed: April 25, 2008
    Publication date: January 1, 2009
    Inventors: Shiro Mazawa, Toshiyuki Saito, Keisuke Takeuchi, Rintaro Katayama