Patents by Inventor Hijin Sato

Hijin Sato 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).

  • Publication number: 20030036409
    Abstract: An autonomous zone forming method of autonomously forming a zone which is a service area of a base station in a wireless communication system having the base station is provided. In the method, it is detected that a zone is newly formed around the base station, and a zone which is the service area of the base station is autonomously changed according to a newly formed zone. When determining the zone, receive quality of a signal received from a surrounding base station is used. In addition, a congestion state of a surrounding base station of the base station is detected, and a zone which is the service area of the base station is enlarged to the direction of the surrounding base station according to the congestion state.
    Type: Application
    Filed: October 3, 2001
    Publication date: February 20, 2003
    Inventors: Hijin Sato, Narumi Umeda, Yosushi Yamao
  • Publication number: 20020163902
    Abstract: In a wireless base station, when a newly provided control unit receives an IP packet from one mobile station (102), it refers to a destination address in control information added to the IP packet (104), and determines whether the IP packet is one to be broadcast or multicast (106). If the value of destination address is at a value indicative of broadcasting or the like defined by IP, the IP packet is copied according to the subnet, and is sent back to a wireless link layer processor with its contents intact (108). Further, the wireless link layer processor is commanded to broadcast the sent-back IP packet in a wireless area and so forth (110), whereby the IP packet can be broadcast into a cell and so forth.
    Type: Application
    Filed: May 1, 2002
    Publication date: November 7, 2002
    Applicant: NTT DoCoMo, Inc.
    Inventors: Toshiaki Takao, Kobaruto Shimada, Narumi Umeda, Hijin Sato
  • Publication number: 20020160777
    Abstract: In handover control methods and systems which switch a radio base station serving as a communicating counterpart of a mobile station, the present invention provides a handover control method and a system thereof wherein a detection is made when a communication while a predetermined minimum bandwidth secured is not possible at any mobile station communicating with the radio base station and upon the detection the communicating counterpart of the mobile station that communicates with the radio base station mentioned above is switched from the radio base station to other radio base stations.
    Type: Application
    Filed: August 28, 2001
    Publication date: October 31, 2002
    Inventors: Toshiaki Takao, Hijin Sato, Narumi Umeda
  • Publication number: 20020123314
    Abstract: A determination part obtains an available communication quality value from required communication quality values of terminals currently on connection, and a maximum permissible communication quality value determined according to a design of the radio communication system, and, when the available communication quality value is larger than a required communication quality value of a new terminal, the determination part accepts connection for the new terminal.
    Type: Application
    Filed: December 27, 2001
    Publication date: September 5, 2002
    Applicant: NTT DoCoMo, Inc
    Inventors: Daisuke Kitazawa, Hijin Sato, Narumi Umeda
  • Publication number: 20020106985
    Abstract: The present invention is configured such that, in a multicast service providing system in which multicast information distribution service is made from an information distributing apparatus to radio terminals present within a service area via a radio section, the radio terminal has service continuation request signal transmitting a service continuation request signal for requesting continuation of the multicast information distribution service to the information distributing apparatus, the information distributing apparatus has service continuation management means managing as to whether or not request for the service continuation has been made by the radio terminal for the multicast information distribution service, and the information distributing apparatus transmits information indicating as to whether or not continuation request has been made for the multicast information distribution service managed by the service continuation management means.
    Type: Application
    Filed: March 25, 2002
    Publication date: August 8, 2002
    Inventors: Hijin Sato, Kobaruto Shimada, Toshiaki Takao, Narumi Umeda
  • Publication number: 20020077142
    Abstract: The present invention allows the cell shape of any base station in operation to be changed, thereby enabling services to be provided according to the needs. A mobile terminal attempts to synchronize with a perch channel to thereby check whether or not it can receive the signal, thereby determining whether it belongs to the cell of the base station. The mobile terminal uses the GPS to obtain location information to identify the location and notifies a cell control apparatus of results for cell determinations and location information. The cell control apparatus selects a base station for which the corresponding cell shape is to be changed, on the basis of the results for cell determinations and the location information. The cell control apparatus instructs the selected base station to change its cell shape. The base station changes its cell shape according to the instruction.
    Type: Application
    Filed: September 27, 2001
    Publication date: June 20, 2002
    Inventors: Hijin Sato, Narumi Umeda
  • Publication number: 20020061766
    Abstract: A base station for use in a multi-network connection communication system and its connecting method are provided, wherein the base station is connectable simultaneously to a carrier network and a private network. The base station comprises a section for making a decision as to whether a terminal is to be connected to a carrier network or a private network, and a section for connecting the terminal to the carrier network or the private network in accordance with the decision result.
    Type: Application
    Filed: November 21, 2001
    Publication date: May 23, 2002
    Inventors: Hijin Sato, Narumi Umeda, Yasushi Yamao
  • Publication number: 20020042275
    Abstract: In a method for allocating radio resource to radio terminals or communication connections in a system in which each of said radio terminals or communication connections requires a different communication quality, a first group including radio terminals or communication connections in which actual communication qualities are degraded more than required communication qualities is retrieved and a second group including radio terminals or communication connections in which actual communication qualities are favorable more than required communication qualities is retrieved. Then, radio resource is allocated to the radio terminals or communication connections in said first group with higher priority than the radio terminals or communication connections in said second group.
    Type: Application
    Filed: October 1, 2001
    Publication date: April 11, 2002
    Applicant: NTT DoCoMo, Inc.
    Inventors: Daisuke Kitazawa, Hijin Sato, Narumi Umeda
  • Publication number: 20020037729
    Abstract: At each wireless terminal, a receiving unit receives a signal transmitted from a wireless base station. A signal-to-noise ratio measurement unit measures an S/N of this received signal. In the wireless base station, data amount measurement unit measures the amount of data stored in each buffer therein. A maximum stay time measurement unit measures a maximum stay time of packets in each buffer. A classification by the maximum stay time unit classifies each wireless terminal based on the maximum stay time.
    Type: Application
    Filed: September 27, 2001
    Publication date: March 28, 2002
    Applicant: NTT DoCoMo, Inc.
    Inventors: Daisuke Kitazawa, Hijin Sato, Narumi Umeda
  • Publication number: 20020028687
    Abstract: In a retransmission control method for a multicast information distribution service, when information which requires retransmission is generated, a wireless terminal transmits the retransmission request for the information to an information distribution apparatus when a timing determined for the wireless terminal is reached. The information distribution apparatus which receives the retransmission request transmits retransmission information which indicates the information requested by the retransmission request, with respect to each of the wireless terminals within the service area, and retransmits the information requested by the retransmission request at a predetermined timing.
    Type: Application
    Filed: August 2, 2001
    Publication date: March 7, 2002
    Applicant: NTT DoCoMo, Inc.
    Inventors: Hijin Sato, Kobaruto Shimada, Toshiaki Takao, Narumi Umeda
  • Publication number: 20020003798
    Abstract: The method of invention provides a multicast service from an information delivery apparatus to wireless terminals through wireless routes. The method includes the step of transmitting, from the information delivery apparatus, a plurality of sets of multicast information, wherein these sets are identical to each other as to contents thereof but differ in transmission conditions. The method further includes the step of receiving, at any given one of the wireless terminals, one of the sets of multicast information being transmitted under one of the differing transmission conditions.
    Type: Application
    Filed: May 3, 2001
    Publication date: January 10, 2002
    Applicant: NTT DoCoMo, Inc.
    Inventors: Hijin Sato, Narumi Umeda, Yasushi Yamao
  • Publication number: 20010049291
    Abstract: A retransmission control method in a multicast service providing system in which an information delivery apparatus delivers multicast information to radio terminals within a service area of the information delivery apparatus, includes two steps. The first step determines at least one radio terminal permitted to be placed in retransmission control. The second step delivers, when a request for retransmission about the multicast information sent by the above-mentioned at least one radio terminal is received by the information delivery apparatus, the multicast information to the radio terminals within the service area.
    Type: Application
    Filed: April 12, 2001
    Publication date: December 6, 2001
    Applicant: NTT DoCoMo, Inc.
    Inventors: Hijin Sato, Kobaruto Shimada, Narumi Umeda, Yasushi Yamao