Patents by Inventor Sadao Obana
Sadao Obana 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).
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Patent number: 9867126Abstract: A wireless base station (1) includes a wakeup device (13) and a main device (14). When the main device (14) is in a sleep mode, the wakeup device (13) is connected to the antenna (11). Then, when the wakeup device (13) receives a wakeup signal for activating the wireless base station (1) from a terminal device assigned to the wireless base station (1) in a communication band used for wireless communication with the terminal device and when the information for identifying a wireless base station to be activated contained in the received wakeup signal is identical with the identification information of the wireless base station (1), the wakeup device (13) outputs a driving signal to the main device (14). The main device (14) transitions from the sleep mode to an operating mode in response to the driving signal from the wakeup device (13).Type: GrantFiled: September 16, 2016Date of Patent: January 9, 2018Assignees: ADVANCED TELECOMMUNICATIONS RESEARCH INSTITUTE INTERNATIONAL, NEC COMMUNICATIONS, LTD.Inventors: Hiroyuki Yomo, Yoshihisa Kondo, Suhua Tang, Sadao Obana, Tetsuya Ito, Akira Matsumoto, Koichi Yoshimura
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Publication number: 20170006540Abstract: A wireless base station (1) includes a wakeup device (13) and a main device (14). When the main device (14) is in a sleep mode, the wakeup device (13) is connected to the antenna (11). Then, when the wakeup device (13) receives a wakeup signal for activating the wireless base station (1) from a terminal device assigned to the wireless base station (1) in a communication band used for wireless communication with the terminal device and when the information for identifying a wireless base station to be activated contained in the received wakeup signal is identical with the identification information of the wireless base station (1), the wakeup device (13) outputs a driving signal to the main device (14). The main device (14) transitions from the sleep mode to an operating mode in response to the driving signal from the wakeup device (13).Type: ApplicationFiled: September 16, 2016Publication date: January 5, 2017Applicants: ADVANCED TELECOMMUNICATIONS RESEARCH INSTITUTE INTERNATIONAL, NEC COMMUNICATION SYSTEMS, LTD.Inventors: Hiroyuki Yomo, Yoshihisa Kondo, Suhua Tang, Sadao Obana, Tetsuya Ito, Akira Matsumoto, Koichi Yoshimura
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Patent number: 9521613Abstract: A wireless base station (1) includes a wakeup device (13) and a main device (14). When the main device (14) is in a sleep mode, the wakeup device (13) is connected to the antenna (11). Then, when the wakeup device (13) receives a wakeup signal for activating the wireless base station (1) from a terminal device assigned to the wireless base station (1) in a communication band used for wireless communication with the terminal device and when the information for identifying a wireless base station to be activated contained in the received wakeup signal is identical with the identification information of the wireless base station (1), the wakeup device (13) outputs a driving signal to the main device (14). The main device (14) transitions from the sleep mode to an operating mode in response to the driving signal from the wakeup device (13).Type: GrantFiled: February 16, 2012Date of Patent: December 13, 2016Assignees: Advanced Telecommunications Research Institute International, NEC Communication Systems, LTD.Inventors: Hiroyuki Yomo, Yoshihisa Kondo, Suhua Tang, Sadao Obana, Tetsuya Ito, Akira Matsumoto, Koichi Yoshimura
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Patent number: 9374784Abstract: A terminal device 2 transmits a wireless frame having a frame length or amplitude that represents the ID of a wireless base station 1 to be woken up to the wireless base station 1. The wireless base station 1 detects the wakeup ID from the frame length or amplitude of the wireless frame from the terminal device 2, and, if the detected wakeup ID is identical with its own ID, transitions from a sleep mode to an operating mode. In this case, the wireless frame is the same wireless frame as that transmitted and received by the wireless communication module of the terminal device 2 to and from the wireless base station 1.Type: GrantFiled: February 16, 2012Date of Patent: June 21, 2016Assignees: ADVANCED TELECOMMUNICATIONS RESEARCH INSTITUTE INTERNATIONAL, NEC COMMUNICATION SYSTEMS, LTD.Inventors: Yoshihisa Kondo, Hiroyuki Yomo, Suhua Tang, Sadao Obana, Tetsuya Ito, Koichi Yoshimura, Masahito Iwai, Toshiyasu Tanaka, Hiroyuki Iizuka
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Patent number: 8755336Abstract: When wireless communications are made between a first wireless device and a second wireless device along a route, two wireless devices which exist between the first and second wireless devices each determine the lowest maximum transmission rate (11 Mbps) in the wireless intervals on the route from themselves to the second wireless device to be their own transmission rate txRate (11 Mbps) and two other wireless devices which exist between the first and second wireless devices each determine the lowest maximum transmission rate (54 Mbps) in the wireless intervals on the route from themselves to the second wireless device to be their own transmission rate txRate (54 Mbps).Type: GrantFiled: February 13, 2008Date of Patent: June 17, 2014Assignees: Nec Communications Systems, Ltd., Advanced Telecommunications Research Institute InternationalInventors: Yoshihisa Kondo, Tetsuya Ito, Akira Matsumoto, Jun Hasegawa, Satoko Itaya, Kenichi Abe, Peter Davis, Naoto Kadowaki, Sadao Obana
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Publication number: 20130336188Abstract: A wireless base station (1) includes a wakeup device (13) and a main device (14). When the main device (14) is in a sleep mode, the wakeup device (13) is connected to the antenna (11). Then, when the wakeup device (13) receives a wakeup signal for activating the wireless base station (1) from a terminal device assigned to the wireless base station (1) in a communication band used for wireless communication with the terminal device and when the information for identifying a wireless base station to be activated contained in the received wakeup signal is identical with the identification information of the wireless base station (1), the wakeup device (13) outputs a driving signal to the main device (14). The main device (14) transitions from the sleep mode to an operating mode in response to the driving signal from the wakeup device (13).Type: ApplicationFiled: February 16, 2012Publication date: December 19, 2013Applicant: NEC COMMUNICATIONS SYSTEMS, LTD.Inventors: Hiroyuki Yomo, Yoshihisa Kondo, Suhua Tang, Sadao Obana, Tetsuya Ito, Akira Matsumoto, Koichi Yoshimura
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Publication number: 20130329621Abstract: A terminal device 2 transmits a wireless frame having a frame length or amplitude that represents the ID of a wireless base station 1 to be woken up to the wireless base station 1. The wireless base station 1 detects the wakeup ID from the frame length or amplitude of the wireless frame from the terminal device 2, and, if the detected wakeup ID is identical with its own ID, transitions from a sleep mode to an operating mode. In this case, the wireless frame is the same wireless frame as that transmitted and received by the wireless communication module of the terminal device 2 to and from the wireless base station 1.Type: ApplicationFiled: February 16, 2012Publication date: December 12, 2013Applicants: NEC COMMUNICATIONS SYSTEMS, LTD., ADVANCED TELECOMMUNICATIONS RESEARCH INSTITUTE INTERNATIONALInventors: Yoshihisa Kondo, Hiroyuki Yomo, Suhua Tang, Sadao Obana, Tetsuya Ito, Koichi Yoshimura, Masahito Iwai, Toshiyasu Tanaka, Hiroyuki Iizuka
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Patent number: 8238319Abstract: Radio apparatuses each has a plurality of channels and, when data is to be transmitted, selects a specific channel having relatively low signal interference from the plurality of channels. Each radio apparatus spreads transmission data with a prescribed spread code arbitrarily selected from a plurality of spread codes, and modulates the spread spectrum signal with the frequency of the specific channel to transmit. As a result, delay in an autonomously established wireless network can be reduced.Type: GrantFiled: August 30, 2007Date of Patent: August 7, 2012Assignee: Advanced Telecommunications Research Institute InternationalInventors: Naoto Kadowaki, Peter Davis, Jun Hasegawa, Akio Hasegawa, Sadao Obana
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Patent number: 8184584Abstract: In wireless communication using links with neighbor wireless devices, a wireless device calculates ratios of throughput to maximum throughput for the links and calculates the costs of the links using the calculated ratios. Then the wireless device finds, for each destination, a route in which the sum of such calculated link costs is the minimum, and sends a packet to the destination using the route. As a consequence, routing can be done according to an isotonic, easy-to-implement routing protocol.Type: GrantFiled: October 23, 2008Date of Patent: May 22, 2012Assignees: NEC Communications Systems, Ltd., Advanced Telecommunications Research Institute InternationalInventors: Yoshihisa Kondo, Satoko Itaya, Peter Davis, Ryutaro Suzuki, Sadao Obana, Tetsuya Ito, Akira Matsumoto
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Patent number: 8121629Abstract: Radio devices (31 to 43) receive a prescribed number of Hello packets from each of n radio devices existing within one hop from each radio device, detects six pairs of maximum and minimum values MAX[1] and MIN[1] to MAX[6] and MIN[6] based on the plurality of reception signal strengths of the plurality of received Hello packets, detects two adjacent maximum values having the largest difference among six pairs of maximum and minimum values D_MAX[1] and D_MIN[1] to D_MAX[6] and D_MIN[6] when the six maximum values MAX[1] to MAX[6] are in descending order, and determines the average of two minimum values corresponding to the detected two maximum values as a threshold. The radio devices (31 to 43) each produce a routing table including routes having reception signal strengths equal to or more than the threshold.Type: GrantFiled: March 29, 2006Date of Patent: February 21, 2012Assignee: Advanced Telecommunications Research Institute InternationalInventors: Peter Davis, Satoko Itaya, Jun Hasegawa, Akio Hasegawa, Naoto Kadowaki, Sadao Obana
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Patent number: 8072925Abstract: A source terminal measures characteristics of the path at the source terminal itself, produces a characteristics-measurement packet, and transmits the produced characteristics-measurement packet to a relay terminal. Upon receiving the characteristics-measurement packet, the relay terminal measures characteristics of the path at the relay terminal itself, renews the characteristics of the path included in the characteristics-measurement packet using the measured characteristics of the path, and transmits the characteristics of the wireless communication path to the destination terminal. The source terminal produces an admission-request packet and transmits the packet to the destination terminal. Upon receiving the admission-request packet, the destination terminal allows or rejects the traffic quality maintenance request according to the characteristics of the wireless communication path.Type: GrantFiled: March 8, 2006Date of Patent: December 6, 2011Assignees: Oki Electric Industry Co., Ltd., Advanced Telecommunications Research Institute International, National Institute of Information and Communications TechnologyInventors: Oyunchimeg Shagdar, Masanori Nozaki, Youiti Kado, Bing Zhang, Mehdad Nori Shirazi, Seiji Igi, Naoto Kadowaki, Sadao Obana
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Patent number: 8060107Abstract: A radio apparatus forming a radio network system calculates a calculated distance, based on a tentative self-position and tentative positions of a plurality of radio apparatuses existing in the vicinity. The radio apparatus successively and autonomously corrects the tentative self-position so that the calculated distance comes closer to the measured distance, relying more heavily on the calculated distance than the measured distance between itself and each of the plurality of radio apparatuses, and determines the position of itself. Other radio apparatuses also successively correct the tentative self-positions by the same method as the radio apparatus, and determine the positions of themselves.Type: GrantFiled: March 30, 2007Date of Patent: November 15, 2011Assignee: Advanced Telecommunications Research Institute InternationalInventors: Yasuhisa Takizawa, Peter Davis, Makoto Kawai, Hisato Iwai, Akira Yamaguchi, Sadao Obana
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Patent number: 8041377Abstract: A radio device is located far from other radio devices in a radio network system. The radio device determines a threshold WIth for detecting a strength equal to or more than the minimum strength of radio waves transmitted/received in a stable radio wave environment based on a plurality of reception signal strengths of Hello packets received from radio devices adjacent to the radio device. Then, if the number of radio devices adjacent to the radio device when the threshold WIth is introduced is less than a standard value (such as five), the radio device stores the adjacent radio devices in the neighbor list without introducing the threshold WIth, and then, maintains in the routing table the routing information of routes passing through the adjacent radio devices based on the neighbor list.Type: GrantFiled: September 27, 2007Date of Patent: October 18, 2011Assignees: NEC Communication Systems Ltd., Advanced Telecommunications Research Institute InternationalInventors: Satoko Itaya, Jun Hasegawa, Akio Hasegawa, Peter Davis, Tetsuya Ito, Akira Matsumoto, Naoto Kadowaki, Sadao Obana
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Patent number: 7890112Abstract: The route maintenance unit outputs a period setting request to the period setting unit when the communication unit normally receives a Hello packet for the first time. The period setting unit sets a link connection confirmation period in response to the period setting request and outputs the set period to the route maintenance unit. The route maintenance unit maintains a radio link between the radio device in which the route maintenance unit is provided and an adjacent device upon receiving a data packet other than a Hello packet from the adjacent radio device even if a Hello packet is not received in the link connection confirmation period. Consequently, route disconnection or switching occurs less often.Type: GrantFiled: September 4, 2007Date of Patent: February 15, 2011Assignees: NEC Communication Systems, Ltd., Advanced Telecommunications Research Institute InternationalInventors: Tetsuya Ito, Jun Hasegawa, Satoko Itaya, Akira Matsumoto, Hiroyuki Iizuka, Yuichiro Ezure, Akio Hasegawa, Peter Davis, Naoto Kadowaki, Sadao Obana
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Publication number: 20090109901Abstract: In wireless communication using links with neighbor wireless devices, a wireless device calculates ratios of throughput to maximum throughput for the links and calculates the costs of the links using the calculated ratios. Then the wireless device finds, for each destination, a route in which the sum of such calculated link costs is the minimum, and sends a packet to the destination using the route. As a consequence, routing can be done according to an isotonic, easy-to-implement routing protocol.Type: ApplicationFiled: October 23, 2008Publication date: April 30, 2009Applicants: NEC Communication Systems, Ltd., Advanced Telecommunications Research Institute InternationalInventors: Yoshihisa KONDO, Satoko ITAYA, Peter DAVIS, Ryutaro SUZUKI, Sadao OBANA, Tetsuya ITO, Akira MATSUMOTO
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Publication number: 20090092083Abstract: A source terminal measures characteristics of the path at the source terminal itself, produces a characteristics-measurement packet, and transmits the produced characteristics-measurement packet to a relay terminal. Upon receiving the characteristics-measurement packet, the relay terminal measures characteristics of the path at the relay terminal itself, renews the characteristics of the path included in the characteristics-measurement packet using the measured characteristics of the path, and transmits the characteristics of the wireless communication path to the destination terminal. The source terminal produces an admission-request packet and transmits the packet to the destination terminal. Upon receiving the admission-request packet, the destination terminal allows or rejects the traffic quality maintenance request according to the characteristics of the wireless communication path.Type: ApplicationFiled: March 8, 2006Publication date: April 9, 2009Applicants: OKI ELECTRIC INDUSTRY CO., LTD., ADVANCED TELECOMMUNICATION RESEARCH INSTITUTE INTERNATIONAL, NATIONAL INSTITUTE OF INFORMATION AND COMMUNICATIONS TECHNOLOGYInventors: Oyunchimeg Shagdar, Masanori Nozaki, Youiti Kado, Bing Zhang, Mehdad Nori Shirazi, Seiji Igi, Naoto Kadowaki, Sadao Obana
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Publication number: 20080192724Abstract: When wireless communications are made between a first wireless device and a second wireless device along a route, two wireless devices which exist between the first and second wireless devices each determine the lowest maximum transmission rate (11 Mbps) in the wireless intervals on the route from themselves to the second wireless device to be their own transmission rate txRate (11 Mbps) and two other wireless devices which exist between the first and second wireless devices each determine the lowest maximum transmission rate (54 Mbps) in the wireless intervals on the route from themselves to the second wireless device to be their own transmission rate txRate (54 Mbps).Type: ApplicationFiled: February 13, 2008Publication date: August 14, 2008Applicants: NEC Communication Systems, Ltd., Advanced Telecommunications Research Institute InternationalInventors: Yoshihisa Kondo, Tetsuya Ito, Akira Matsumoto, Jun Hasegawa, Satoko Itaya, Kenichi Abe, Peter Davis, Naoto Kadowaki, Sadao Obana
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Publication number: 20080125069Abstract: Radio devices (31 to 43) receive a prescribed number of Hello packets from each of n radio devices existing within one hop from each radio device, detects six pairs of maximum and minimum values MAX[1] and MIN[1] to MAX[6] and MIN[6] based on the plurality of reception signal strengths of the plurality of received Hello packets, detects two adjacent maximum values having the largest difference among six pairs of maximum and minimum values D_MAX[1] and D_MIN[1] to D_MAX[6] and D_MIN[6] when the six maximum values MAX[1] to MAX[6] are in descending order, and determines the average of two minimum values corresponding to the detected two maximum values as a threshold. The radio devices (31 to 43) each produce a routing table including routes having reception signal strengths equal to or more than the threshold.Type: ApplicationFiled: March 29, 2006Publication date: May 29, 2008Inventors: Peter Davis, Satoko Itaya, Jun Hasegawa, Akio Hasegawa, Naoto Kadowaki, Sadao Obana
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Publication number: 20080076461Abstract: A radio device is located far from other radio devices in a radio network system. The radio device determines a threshold WIth for detecting a strength equal to or more than the minimum strength of radio waves transmitted/received in a stable radio wave environment based on a plurality of reception signal strengths of Hello packets received from radio devices adjacent to the radio device. Then, if the number of radio devices adjacent to the radio device when the threshold WIth is introduced is less than a standard value (such as five), the radio device stores the adjacent radio devices in the neighbor list without introducing the threshold WIth, and then, maintains in the routing table the routing information of routes passing through the adjacent radio devices based on the neighbor list.Type: ApplicationFiled: September 27, 2007Publication date: March 27, 2008Inventors: Satoko Itaya, Jun Hasegawa, Akio Hasegawa, Peter Davis, Tetsuya Ito, Akira Matsumoto, Naoto Kadowaki, Sadao Obana
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Publication number: 20080062901Abstract: Radio apparatuses each has a plurality of channels and, when data is to be transmitted, selects a specific channel having relatively low signal interference from the plurality of channels. Each radio apparatus spreads transmission data with a prescribed spread code arbitrarily selected from a plurality of spread codes, and modulates the spread spectrum signal with the frequency of the specific channel to transmit. As a result, delay in an autonomously established wireless network can be reduced.Type: ApplicationFiled: August 30, 2007Publication date: March 13, 2008Inventors: Naoto Kadowaki, Peter Davis, Jun Hasegawa, Akio Hasegawa, Sadao Obana