Patents by Inventor Daisuke Kitazawa

Daisuke Kitazawa 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: 20050186982
    Abstract: The present invention improves a system capacity and satisfaction rate with a quality of service in packet communications performed through a radio link established between a transmitting station and a receiving station by dynamically limiting transmission power of packets in the transmitting station and keeping an increase of an interference level in the receiving station, which belongs to another cell, within a TPC margin. The present invention includes a resource allocator 115 configured to set transmission power of packets in a next step period, by use of transmission power of packets in a preceding step period (slot) and an interference level of the receiving station.
    Type: Application
    Filed: June 6, 2003
    Publication date: August 25, 2005
    Inventors: Lan Chen, Daisuke Kitazawa, Hidetoshi Kayama, Narumi Umeda
  • Patent number: 6921589
    Abstract: The present invention relates to an electroluminescent element formed by placing a luminescing substance between an anode and a cathode, such that when electrical energy is applied to the element, light is emitted having a peak wavelength of at least 580 nm. The luminescing substance comprises a fluorescent compound have a fluorescent maximum at about 540 nm or above and a compound having a pyrromethene structure (I) or metal complexes thereof.
    Type: Grant
    Filed: June 18, 2002
    Date of Patent: July 26, 2005
    Assignee: Toray Industries, Inc.
    Inventors: Akira Kohama, Tsuyoshi Tominaga, Daisuke Kitazawa, Yoshio Himeshima
  • Publication number: 20050025056
    Abstract: In a packet communications method of performing packet communications between a mobile station and a base station, the base station manages an amount of packets stored in a transmission buffer of the mobile station. The mobile station notifies a changed result of an amount of packets stored in the transmission buffer of the mobile station, when the amount of packets stored in the transmission buffer of the mobile station changes. The base station changes a managed amount in accordance with the changed result notified from the mobile station.
    Type: Application
    Filed: May 14, 2004
    Publication date: February 3, 2005
    Applicant: NTT DoCoMo, Inc.
    Inventors: Lan Chen, Daisuke Kitazawa, Hidetoshi Kayama, Narumi Umeda
  • Publication number: 20040132405
    Abstract: An object of the present invention is to support various QoSs and to use resources effectively in a radio communication system. In a radio communication system where, concerning the maximum allowable delay and the reception error rate as required values for QoS, a first mobile station group of which the maximum allowable delay is less than a reference value and the reception error rate is a reference value or more, and a second mobile station group of which the maximum allowable delay is a reference value or more and the reception error rate is less than a reference value coexist, the base station sets the transmission power margin for a mobile station of the first mobile station group to be higher than the transmission power margin for a mobile station of the second mobile station group, and a mobile station of the first mobile station group sets the transmission power margin to be higher than the transmission power margin of a mobile station of the second mobile station group.
    Type: Application
    Filed: September 30, 2003
    Publication date: July 8, 2004
    Applicant: NTT DoCoMo, Inc
    Inventors: Daisuke Kitazawa, Lan Chen, Hidetoshi Kayama, Narumi Umeda
  • Publication number: 20040082364
    Abstract: A base station comprises a packet classification unit configured to classify packets received/transmitted from/to a plurality of mobile stations into a quantitative guarantee type packet having a request value for communication quality or a relative guarantee type packet not having the request value, and a transmission order controller configured to control a transmission order of the packets for every classified quantitative guarantee type packet and every classified relative guarantee type packet.
    Type: Application
    Filed: October 16, 2003
    Publication date: April 29, 2004
    Applicant: NTT DoCoMo, Inc.
    Inventors: Daisuke Kitazawa, Lan Chen, Hidetoshi Kayama, Narumi Umeda
  • Publication number: 20040028006
    Abstract: The object is to suppress interference to other packets under transmission and decrease the error rate of packets. A mobile station first starts transmitting a packet A stored and then starts transmitting a packet B after a predetermined period of time &tgr;s. Thereafter, the mobile station starts transmitting packets C, D in order at intervals of the predetermined time period &tgr;s. Since each packet is assigned an individual code and transmitted at a relatively low transmission rate, packets are transmitted in an overlapping state when the predetermined period &tgr;s is set sufficiently short. The transmission power of the mobile station is in a gently stepped state.
    Type: Application
    Filed: May 21, 2003
    Publication date: February 12, 2004
    Applicant: NTT DoCoMo, Inc.
    Inventors: Hidetoshi Kayama, Lan Chen, Daisuke Kitazawa, Narumi Umeda
  • Publication number: 20030169746
    Abstract: A mobile communications base station has a service quality detection unit that monitors and measures communication qualities of wireless terminals currently located in the service area, and a packet classification unit that classifies packets addressed to the wireless terminals into two or more groups based on the measured communication qualities. The base station also has a buffering delay measuring unit that measures buffering delay of the packets for each of the groups. A transmission priority detection unit of the base station determines the order of priority for transmitting the packets based on the measured buffering delay in comparison with a prescribed threshold value. A resource allocation unit of the base station allocates the radio resources to the packets based on the order of priority to transmit the packets to the associated wireless terminals.
    Type: Application
    Filed: March 5, 2003
    Publication date: September 11, 2003
    Applicant: NTT DoCoMo, Inc.
    Inventors: Daisuke Kitazawa, Lan Chen, Hidetoshi Kayama, Narumi Umeda
  • Publication number: 20030168970
    Abstract: The light emitting device of the present invention relates to a light emitting device which is characterized in that it is a device with an emissive substance present between an anode and cathode, and which emits light by means of electrical energy, and said device has a least one type of compound denoted by (a) to (d) below.
    Type: Application
    Filed: September 11, 2002
    Publication date: September 11, 2003
    Inventors: Tsuyoshi Tominaga, Daisuke Kitazawa, Aki Makiyama, Akira Kohama
  • Publication number: 20020160227
    Abstract: The objective of the present invention lies in offering red electroluminescent elements which have a high electrical energy utilization efficiency and outstanding colour purity.
    Type: Application
    Filed: June 18, 2002
    Publication date: October 31, 2002
    Inventors: Akira Kohama, Tsuyoshi Tominaga, Daisuke Kitazawa, Yoshio Himeshima
  • 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: 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