Patents by Inventor Tetsuya Kawakami

Tetsuya Kawakami 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: 8503343
    Abstract: A technique is disclosed, by which it is possible to achieve the reduction of power consumption of each wireless node and to perform efficient access control in wireless communication system. According to this technique, a given period with a beacon transmitted from a gateway (GW) 100 at the foremost position is divided to an active period where each wireless node (P2P tag) transmits and receives a frame and a sleep period where transmitting and receiving of the frames are stopped. Further, the active period is divided to a plurality of timeslots each with a fixed length, and the period is partitioned to sub-periods where each type of a GW, a fixed node (P2P-S tag), and a mobile node (P2P-M tag) can transmit frames respectively. Each of the P2P tags selects a timeslot at random from the period for each type, and after waiting for a waiting period at random at the selected timeslot, it transmits a frame including information to identify the selected timeslot or the waiting period in addition to its own ID.
    Type: Grant
    Filed: August 17, 2007
    Date of Patent: August 6, 2013
    Assignee: Panasonic Corporation
    Inventors: Tetsuya Kawakami, Michiru Yokobori, Kazuhiko Miyamoto, Yoshihiro Suzuki
  • Patent number: 8155085
    Abstract: A technology is disclosed in which, when a normal mobile node (that does not newly provide a dedicated function) is used, signaling for reconfiguring a tunnel during a mobile node movement is reduced and, furthermore, packet loss is reduced. In the technology, when an MN moves from under the control of an AR2 that is a movement origin to be under the control of an AR3 that is a movement destination, the AR3 receives an NS transmitted from the MN to the AR2. The AR3 that receives the NS destined to the AR2 transmits a “Location Update” to the AR2. The AR2 that receives the “Location Update” uses an MN management table of the relevant MN and creates “Prefix Information” and returns the “Prefix Information” to the AR3. A tunnel is established between access routers of the AR2 and AR3 through use of the “Prefix Information”, and a packet destined to the MN is transferred to the MN via the tunnel.
    Type: Grant
    Filed: July 26, 2007
    Date of Patent: April 10, 2012
    Assignee: Panasonic Corporation
    Inventors: Tetsuya Kawakami, Genadi Velev, Jon Schuringa
  • Patent number: 8140011
    Abstract: The present invention provides a radio node apparatus, a multi-hop radio system and a multi-hop radio system constructing method, capable of constructing a tree type multi-hop radio system in which mutual radio nodes determine a radio node which becomes a root node of a tree in an autonomous manner and the root node is set as a root in an autonomous manner.
    Type: Grant
    Filed: November 16, 2010
    Date of Patent: March 20, 2012
    Assignees: Panasonic Corporation, National Institute of Information and Communications Technology
    Inventors: Tetsuya Kawakami, Yoshihiro Suzuki, Masayuki Fujise
  • Patent number: 8072949
    Abstract: A wireless node apparatus in a multihop wireless LAN with a tree structure having a plurality of wireless node apparatuses, at least some of which become relay apparatuses to provide multihop communication, transfers packets among wireless nodes as done in a tree type LAN, without intervening a root node, to communicate among the wireless nodes.
    Type: Grant
    Filed: April 25, 2005
    Date of Patent: December 6, 2011
    Assignee: Panasonic Corporation
    Inventors: Tetsuya Kawakami, Yoshihiro Suzuki
  • Publication number: 20110065380
    Abstract: The present invention provides a radio node apparatus, a multi-hop radio system and a multi-hop radio system constructing method, capable of constructing a tree type multi-hop radio system in which mutual radio nodes determine a radio node which becomes a root node of a tree in an autonomous manner and the root node is set as a root in an autonomous manner.
    Type: Application
    Filed: November 16, 2010
    Publication date: March 17, 2011
    Applicants: PANASONIC CORPORATION, National Institute of Information and Communications Technology
    Inventors: Tetsuya Kawakami, Yoshihiro Suzuki, Masayuki Fujise
  • Patent number: 7885601
    Abstract: The present invention provides a radio node apparatus, a multi-hop radio system and a multi-hop radio system constructing method, capable of constructing a tree type multi-hop radio system in which mutual radio nodes determine a radio node which becomes a root node of a tree in an autonomous manner and the root node is set as a root in an autonomous manner.
    Type: Grant
    Filed: August 4, 2005
    Date of Patent: February 8, 2011
    Assignees: Panasonic Corporation, National Institute of Information and Communications Technology
    Inventors: Tetsuya Kawakami, Yoshihiro Suzuki, Masayuki Fujise
  • Publication number: 20100278087
    Abstract: A technique is disclosed, by which it is possible to achieve the reduction of power consumption of each wireless node and to perform efficient access control in wireless communication system. According to this technique, a given period with a beacon transmitted from a gateway (GW) 100 at the foremost position is divided to an active period where each wireless node (P2P tag) transmits and receives a frame and a sleep period where transmitting and receiving of the frames are stopped. Further, the active period is divided to a plurality of timeslots each with a fixed length, and the period is partitioned to sub-periods where each type of a GW, a fixed node (P2P-S tag), and a mobile node (P2P-M tag) can transmit frames respectively. Each of the P2P tags selects a timeslot at random from the period for each type, and after waiting for a waiting period at random at the selected timeslot, it transmits a frame including information to identify the selected timeslot or the waiting period in addition to its own ID.
    Type: Application
    Filed: August 17, 2007
    Publication date: November 4, 2010
    Applicant: PANASONIC CORPORATION
    Inventors: Tetsuya Kawakami, Michiru Yokobori, Kazuhiko Miyamoto, Yoshihiro Suzuki
  • Publication number: 20100202344
    Abstract: Disclosed is a technique which reduces the packet loss and the band consumption for data transfer when a mobile terminal conducts the handover between a fixed base station and a mobile base station for group movement. According to this technique, when an MH (mobile terminal) 320 conducts the handover from a fixed base station (E-LSR 230) positioned at an edge of an access network 200 to a mobile base station (MEB 310) located in a train or the like, a predetermined flag is appended to a frame addressed to the MH in a label switching router (P-LSR 210) positioned at a core network 100 side edge of the access network. The frame having the appended flag is copied in the E-LSR 230. One frame after copied is transmitted directly from the E-LSR to the MH while the other frame after copied is transferred from the E-LSR to the MEB and then transmitted from the MEB to the MH, thus realizing the soft handover.
    Type: Application
    Filed: June 30, 2006
    Publication date: August 12, 2010
    Applicant: MATSUSHITA ELECTRIC INDUSTRIAL CO., LTD.
    Inventor: Tetsuya Kawakami
  • Publication number: 20100151789
    Abstract: The present invention discloses a technique, according to which estimation of a position of a mobile wireless device can be accomplished in a simple system configuration by using short distance communication functions. A plurality of standard stations 110 and a plurality of connecting stations 120 are installed within a predetermined area. A mobile wireless device moving within the predetermined area has short distance wireless communication functions and receives a device ID of an opponent device (a correspondent device) each time it intersects another mobile wireless device or a standard station, and stores the device ID as an intersecting history data. When the mobile wireless device moves to a position where it can perform communication to and from a connecting station, which can make access to a position estimation device 150, the stored intersecting history data is uploaded to the position estimation device.
    Type: Application
    Filed: May 30, 2008
    Publication date: June 17, 2010
    Applicant: PANASONIC CORPORATION
    Inventors: Yoshihiro Suzuki, Tetsuya Kawakami
  • Publication number: 20100118698
    Abstract: Disclosed is a technique to prevent a collision in a state that radio communication devices are congested. According to the technique, in the state that the radio communication devices are congested, one of the radio communication devices becomes a representative node and transmits a representative node advertisement message. When the representative node has received a data packet after transmission of the representative node advertisement message, it transmits a response confirmation message. When a radio communication device, which was not decided as the representative node, has become a normal node and received the representative node advertisement message, it transmits a data packet. Then, when receiving a confirmation message after transmission of the data packet, the radio communication device stops data packet transmission during the next active period.
    Type: Application
    Filed: July 28, 2007
    Publication date: May 13, 2010
    Applicant: PANASONIC CORPORATION
    Inventors: Michiru Yokobori, Tetsuya Kawakami, Kazuhiko Miyamoto, Yoshihiro Suzuki
  • Publication number: 20100014888
    Abstract: The present invention relates to an electrophotographic photosensitive member 2 including a conductive body 20, a photoconductive layer 22 formed on the conductive body 20 using amorphous silicon, and a surface layer 23 formed on the photoconductive layer using amorphous silicon. The present invention further relates to an image forming apparatus provided with the electrophotographic photosensitive member 2. The photoconductive layer 22 has a mean roughness Ra of not more than 10 nm per 10 ?m square. The surface layer 23, without undergoing grinding process, has a mean roughness Ra of not more than 10 nm per 10 ?m square.
    Type: Application
    Filed: May 26, 2006
    Publication date: January 21, 2010
    Applicant: KYOCERA CORPORATION
    Inventors: Akihiko Ikeda, Daigorou Ookubo, Tetsuya Kawakami, Takashi Nakamura, Masamitsu Sasahara, Daisuke Nagahama, Tomomi Fukaya
  • Publication number: 20100002652
    Abstract: A technology is disclosed in which, when a normal mobile node (that does not newly provide a dedicated function) is used, signaling for reconfiguring a tunnel during a mobile node movement is reduced and, furthermore, packet loss is reduced. In the technology, when an MN moves from under the control of an AR2 that is a movement origin to be under the control of an AR3 that is a movement destination, the AR3 receives an NS transmitted from the MN to the AR2. The AR3 that receives the NS destined to the AR2 transmits a “Location Update” to the AR2. The AR2 that receives the “Location Update” uses an MN management table of the relevant MN and creates “Prefix Information” and returns the “Prefix Information” to the AR3. A tunnel is established between access routers of the AR2 and AR3 through use of the “Prefix Information”, and a packet destined to the MN is transferred to the MN via the tunnel.
    Type: Application
    Filed: July 26, 2007
    Publication date: January 7, 2010
    Applicant: PANASONIC CORPORATION
    Inventors: Tetsuya Kawakami, Genadi Velev, Jon Schuringa
  • Publication number: 20090219832
    Abstract: The invention relates to a method for fast configuring of a default router for a mobile node in a mobile communication system. A default router is used by a mobile node to transmit outgoing data to. The mobile node moves from a first to a second network area, which are respectively connected to a first and second router. In order to update the default router, after changing an attachment of the mobile node to the network, the new second router is adapted to transmit a notification to the mobile node, for changing its default router to the new router. According to the invention, the second router may also transmit a message to inform the mobile node about an expiration of the old first router. The new router may also send a message, including an indication about a new rust-hop router for the outgoing data of the mobile node.
    Type: Application
    Filed: March 5, 2007
    Publication date: September 3, 2009
    Applicant: MATSUSHITA ELECTRIC INDUSTRIAL CO., LTD.
    Inventors: Genadi Velev, Tetsuya Kawakami, Jon Schuringa, Rolf Hakenberg
  • Publication number: 20090078566
    Abstract: The present invention relates to a method of forming a deposited film including a first step for setting a deposited film forming target (10) into a reaction chamber (4), a second step for filling the reaction chamber (10) with a reaction gas and a third step for applying pulse DC voltage between a first conductor (3) and a second conductor (40) spaced from each other in the reaction chamber (10). The present invention further relates to a deposited film forming device for performing the above method. Preferably, in the third step, potential difference between the first conductor (3) and the second conductor (40) is set to not less than 50V and not more than 3000V, and pulse frequency of the pulse DC voltage applied to the first and second conductors (3, 40) is set to not more than 300kHz. Duty ratio of the pulse DC voltage is set to not less than 20% and not more than 90%.
    Type: Application
    Filed: June 1, 2006
    Publication date: March 26, 2009
    Applicant: KYOCERA CORPORATION
    Inventors: Akihiko Ikeda, Daigorou Ookubo, Tetsuya Kawakami, Takashi Nakamura, Masamitsu Sasahara, Daisuke Nagahama, Tomomi Fukaya
  • Publication number: 20090016277
    Abstract: Disclosed is a technique for providing a mobile communication access system, etc., that can eliminate a useless consumption of resources due to route redundancy, reduce a load on the LSR processing, such as the setup of an LSP, avoid an increase in the length of a signal route, suppress a delay in providing a notification of the change for an LSR to which a mobile terminal is to be connected. According to this technique, a second edge device 101b obtains an identifier for a label switch path designated as being used for a mobile terminal 100 and an address for a communication destination edge device 101c, and employs the obtained information for a path and outputs a path setup request packet to the communication destination edge device to request a setup for a path to the second edge device.
    Type: Application
    Filed: July 28, 2005
    Publication date: January 15, 2009
    Applicant: MATSUSHITA ELECTRIC INDUSTRIAL CO., LTD.
    Inventor: Tetsuya Kawakami
  • Publication number: 20090010201
    Abstract: Disclosed is a technique for providing a mobile communication access system, etc., that can eliminate the useless consumption of resources due to route redundancy, reduce the load on the processing, such as the setup of an LSP, performed by an ingress LSR, avoid an increase in the length of a signal route for setting up an LSP, suppress a delay in providing a notification of a change for an egress LSR to which a mobile terminal is to be connected, and perform a rapid handover process. According to this technique, based on identification information for a second edge device 101b that is received from a mobile terminal 100, a first edge device 101a determines whether an output interface that has been decided on for the second edge device is the same as an input interface for a path that has been established for the mobile terminal, and when the interfaces are the same, transmits a path request message to the other packet transfer device.
    Type: Application
    Filed: July 28, 2005
    Publication date: January 8, 2009
    Applicant: Matsushita Electric Industrial Co., Ltd.
    Inventor: Tetsuya Kawakami
  • Publication number: 20080139173
    Abstract: A technology for providing an access network system that can reduce the load of a connection authentication of a connection to an access network, upon dividing authentication into the connection authentication of the connection to the access network and a connection authentication of a connection to an external IP network, is disclosed. According to the technology, a first base station device 104a and a second base station device 104b are included. The first base station device is connected to a mobile node 101. The first base station device receives a first authentication request from the mobile node, transmits the first authentication request to an authentication device 102, and receives a first authentication result from the authentication device. The second base station device is newly connected to the mobile node by movement of the mobile node after the mobile node and the first base station device are connected.
    Type: Application
    Filed: December 19, 2005
    Publication date: June 12, 2008
    Applicant: MATSUSHITA ELECTRIC INDUSTRIAL CO., LTD.
    Inventors: Michiru Yokobori, Tetsuya Kawakami, Yoshihiro Suzuki
  • Publication number: 20080037558
    Abstract: There is disclosed an access network system capable of improving throughput even when a single relay device is arranged for different communication routes between an ISP device and a plurality of subscriber terminal devices. In this system, each of the subscribers (111 to 114) and relay stations (105) sets a VLAN so that one VLAN becomes a line. By VLAN-tagging to the packet of the subscriber data, the subscriber data is transferred via the VLAN. The access network system (100) generates MAC address tag information having a destination MAC address indicating the subscriber station which is an edge of the route of the VLAN, a source MAC address indicating the subscriber station corresponding to the route of the VLAN, and a VLAN tag and adds the MAC address tag information to the subscriber data.
    Type: Application
    Filed: April 26, 2005
    Publication date: February 14, 2008
    Applicant: MATSUSHITA ELECTRIC INDUSTRIAL CO., LTD
    Inventor: Tetsuya Kawakami
  • Publication number: 20070291679
    Abstract: Disclosed is a technique of transferring packets among wireless nodes as done in a tree type LAN, without intervening a root node to achieve efficient communications among the wireless nodes. According to the technique, a multihop wireless LAN is constructed by wireless nodes in such a way that it is determined whether or not a wireless node is a root node upon activation; when it is determined that the wireless node is the root node, status information is notified to wireless nodes to be connected, when it is determined that the wireless node is not the root node, wireless nodes to be connection candidates are requested to acquire status information, a higher-rank base station wireless node to be connected is selected and connected based on the status information, and when the wireless node apparatus is made a connection candidate later, status information is notified to wireless nodes.
    Type: Application
    Filed: April 25, 2005
    Publication date: December 20, 2007
    Applicant: MATSUSHITA ELECTRIC INDUSTRIAL CO., LTD.
    Inventors: Tetsuya Kawakami, Yoshihiro Suzuki
  • Publication number: 20070217364
    Abstract: The present invention discloses a technique to reduce packet loss during the handover of a mobile terminal and to eliminate wasteful consumption of band. According to this technique, a connection station 103 and a radio base station 104 where a mobile terminal 100 is connected generate a plurality of own MAC addresses based on identification information of the mobile terminal, and when the handover is started, a network management unit 106 makes up a point-to-multipoint VLAN path where VLAN path between new radio base station device and the connection station device is added to the VLAN path between previous radio base station device and the connection station device, and the connection station device adds a broadcast address, a MAC address of the connection station device, and an identification information of the mobile terminal to a packet received from the external IP network 101, and the packet is transferred via the point-to-multipoint VLAN path.
    Type: Application
    Filed: May 12, 2005
    Publication date: September 20, 2007
    Applicant: MATSUSHITA ELECTRIC INDUSTRIAL CO., LTD.
    Inventor: Tetsuya Kawakami