Patents by Inventor Keiichi Obara

Keiichi Obara 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: 6226268
    Abstract: An information communication system in which a switch constituting section (2) housing a data generating source is connected to a center switch constituting section (1) through a communication channel (3) using an ATM technology as if the function of an ATM switch of distributed arrangement type was realized. This information communication system flexibly handles new kinds of information provided with the progress of times, and, even when a fault occurs, properly copes with the fault.
    Type: Grant
    Filed: November 10, 1997
    Date of Patent: May 1, 2001
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Tomoo Kunikyo, Keiichi Obara, Kazuo Nogami, Tamiya Ochiai
  • Patent number: 6038237
    Abstract: This relates to a voice signal transmitting method and exchange system using this whereby excellent speech quality can be maintained by reducing the celling delay on voice compression and celling/decelling delay on relay-exchanging. Voice compression/framing/celling units 20A, 20B, 20C corresponding to ATM exchanges 10A, 10B, 10C within the network are provided. When a call is made between telephone set 50-1 and telephone set 50-3 or 50-5, voice compression/framing/celling unit 20A distributes the voice signal that is input from PBX 30A to each remote party PBX 30B, 30C; the voice signal distributed to each of these remote stations is compressed, and, at fixed time intervals, only busy channels are multiplexed on to a variable-length TDM frame, this multiplexed frame being then converted into ATM cell form at each PBX 30B, 30C and transferred from ATM exchange 10A to ATM exchange 10B or 10C.
    Type: Grant
    Filed: July 3, 1997
    Date of Patent: March 14, 2000
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Hidekazu Tsuruta, Keiichi Obara
  • Patent number: 6034944
    Abstract: A communication system capable of reliably recovering its communication functions on its own when a fault occurs, and which can be used to construct a highly flexible network. This communication system is configured so that a plurality of node devices (12) supporting data generating sources are connected via communication paths (13) that use ATM technology to a plurality of center devices (11), just as if it possessed distributed ATM switch functions. When the communication paths (13) between two (2) node devices (12-2 and 12-3) are cut, the center device (11-2) detects the fault point, and autonomously recovers communication functions by transferring the node device (12-2) originally under its control to the control of the center device (11-1). When this happens, the center device 11-2) cannot communicate via the communication paths (13) due to the fault, and must use a local communication means such as a wide area network (16) to communicate with the center device (11-1).
    Type: Grant
    Filed: July 3, 1997
    Date of Patent: March 7, 2000
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Yutaka Seki, Keiichi Obara, Tomoo Kunikyou, Hidekazu Turuta, Hirotaka Sakajiri
  • Patent number: 5566179
    Abstract: A broadband switching network for transmitting information by using a cell composed of an information field and a header, including a first network comprising an ATM ring having a plurality of access nodes for multiplexing and demultiplexing the cell and a ring shape transmission path for connecting the plurality of access nodes in a ring shape so as to transmit the cell, and at least one second network, wherein the first network being connected to at least one second network via one of the plurality of access nodes, each second network having a switching function for switching the cell.
    Type: Grant
    Filed: September 30, 1994
    Date of Patent: October 15, 1996
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Hiroshi Kobayashi, Toshikazu Kodama, Keiichi Obara
  • Patent number: 5204857
    Abstract: An ATM exchange system capable of accommodation not only terminals of an ATM system but also terminals of an STM system at low cost. The ATM system includes an ATM channel switch for providing a direct exchange connection between the ATM terminal and an ATM trunk line, an STM channel switch for providing a direct exchange connection between the STM terminal and an STM trunk line, and an STM/ATM conversion module connected between the ATM channel switch and the STM channel switch and adapted to convert a call of one system to that of another system when a call is made between ATM terminal/line and STM terminal/line.
    Type: Grant
    Filed: August 20, 1991
    Date of Patent: April 20, 1993
    Assignee: Kabushiki Kaisha Toshiba
    Inventor: Keiichi Obara
  • Patent number: 4924458
    Abstract: A multiplex communication system includes a plurality of exchanges and multiplex communication apparatuses connected to at least one exchange through a plurality of lines. Each of the multiplex communication apparatuses comprises first registers for storing first selection number information from the lines and second registers for fetching and storing second selection number information from an associated one of the exchanges, and is arranged such that a CPU of the associated communication apparatus determines that the exchange is to perform its interrupting operation and causes encoders and decoders to be switched to their through mode when the first selection number information stored in the first registers coincides with the second selection number information stored in the second registers.
    Type: Grant
    Filed: June 16, 1988
    Date of Patent: May 8, 1990
    Assignee: Kabushiki Kaisha Toshiba
    Inventor: Keiichi Obara
  • Patent number: 4771335
    Abstract: A communication system which includes two digital terminal stations connected to each other by a digital communication line. The communication system includes data terminals adapted for operation on an analog communication line which transmits main data and control data. The data terminal has two modems for transmitting respective data. Correspondingly, the digital terminal station has two modems which modulate and demodulate the respective data signal for transmitting the data from the digital communication line through the analog communication line and vice versa. The data transmission between two data terminals through the digital terminal stations is completed in one transmission call.
    Type: Grant
    Filed: July 9, 1986
    Date of Patent: September 13, 1988
    Assignee: Kabushiki Kaisha Toshiba
    Inventor: Keiichi Obara