Patents Assigned to Kokusai Denshin Denwa Co., Ltd.
  • Patent number: 6975624
    Abstract: A network interworking device used in a communication system which has a first communication network with an IP, a second communication network and a plurality of other network interworking devices connected to the first communication network, the network interworking device being connected between the first communication network and the second communication network for converting IP packets communicated in the first communication network and information signals communicated in the second communication network with each other. The network interworking device includes a packet assembler unit for assembling information signals of a plurality of calls received from the second communication network into a single IP packet when the plurality of calls are to be transmitted to the same network interworking device.
    Type: Grant
    Filed: October 13, 1998
    Date of Patent: December 13, 2005
    Assignee: Kokusai Denshin Denwa Co., Ltd.
    Inventors: Toshikane Oda, Hideaki Yamada, Tohru Asami
  • Patent number: 6856650
    Abstract: At second or later generation coding of video signal in tandem video coding, at least one coding parameter of previous coding is estimated in accordance with picture properties of the input video signal, and the estimated coding parameter in the previous coding is used in the second or later coding.
    Type: Grant
    Filed: July 11, 1997
    Date of Patent: February 15, 2005
    Assignee: Kokusai Denshin Denwa Co., Ltd.
    Inventors: Yasuhiro Takishima, Shigeyuki Sakazawa, Masahiro Wada
  • Patent number: 6456617
    Abstract: A routing control communication system includes a circuit switched network provided with a service control information database having a telephone numbers table, an interconnection network provided with a network communication protocol and an information terminal, and a network interworking equipment provided with one terminal connected with the circuit switched network and the other terminal connected with the interconnection network. The information database is connected with the interconnection network, and the information terminal of the interconnection network is constituted so as to obtain a transferred terminal number corresponding to a called telephone number from the service control information database.
    Type: Grant
    Filed: August 11, 1998
    Date of Patent: September 24, 2002
    Assignee: Kokusai Denshin Denwa Co., Ltd.
    Inventors: Toshikane Oda, Hideaki Yamada, Hikaru Yagi, Hiroto Masaki
  • Patent number: 6445478
    Abstract: Detection of an optical pulse position uses an optical pulse string with a determined repetitive ratio and an electric clock signal with a same frequency as the repetitive ratio of the optical pulse string. A phase of the electric clock signal oscillator is shifted and supplied to an optical modulator. The optical modulator modulates the optical pulse string based on the electric clock signal and outputs a modulated optical signal. A photo detector converts the modulated optical signal output from the optical modulator to an electric signal. The phase shift amount of the electric clock signal is controlled to maximize an output from the photo detector. Additionally, a dither signal may be used in the control of the phase shift, more than the optical modulator may be employed, and/or more than color light source may be employed. The use of at least one of feed forward and feedback control provided by maximizing an output of the photo detector allows an optical pulse having a short width to be realized.
    Type: Grant
    Filed: January 19, 2001
    Date of Patent: September 3, 2002
    Assignees: Mitsubishi Denki Kabushiki Kaisha, Kokusai Denshin Denwa Co., Ltd.
    Inventors: Katsuhiro Shimizu, Takashi Mizuochi, Takeshi Komiya, Kiwami Matsushita, Tadayoshi Kitayama, Masatoshi Suzuki, Hidenori Taga, Shu Yamamoto, Noboru Edagawa, Itsuro Morita
  • Patent number: 6324166
    Abstract: A call setup control apparatus has a first calculation unit for calculating an objective value of cell loss ratio PB(u) of a buffer Bu in priority class u which is equal to or lower than a priority class k (u=k to K), based upon parameters of an average cell rate R(k,j), an objective value of cell loss ratio Q(k,j), and the number of calls N(k,j) for calls of each type j (J=1 to Jk) in each class k (=1 to K), with considering a cell rate of calls in priority class which is higher than the class k (class 1 to k−1), when a fresh call is arrived, a unit for obtaining a bandwidth &agr;(k,u,j) required for calls of type j in class k in the buffer Bu to make a cell loss ratio in the buffer Bu to be equal to or less than the objective value PB(u), a second calculation unit for calculating a required bandwidth C(u) for the buffer Bu, based upon the obtained bandwidth &agr;(k,u,j), and a unit for judging whether the fresh call is acceptable or not by comparing the calculated bandwidth C(u) w
    Type: Grant
    Filed: July 2, 1998
    Date of Patent: November 27, 2001
    Assignee: Kokusai Denshin Denwa Co., Ltd.
    Inventors: Hiroyuki Yokoyama, Hajime Nakamura
  • Patent number: 6317534
    Abstract: An optical wavelength routing device comprises an arrayed waveguide comprising a plurality of channel waveguides formed on a substrate, a plurality of input waveguides having 12 input ports located on an input side of the arrayed waveguide, a plurality of output waveguides having 16 input ports located on an output side of the arrayed waveguide, an input slab waveguide for coupling the plurality of input waveguides to the arrayed waveguide to provide a first coupling portion on the side of the input waveguide, and an output slab waveguide for coupling the arrayed waveguide to the plurality of output waveguides to provide a second coupling portion on the side of the output waveguide, in which central wavelengths of lights input to the input ports and output from the output ports are controlled such that a difference between a predetermined wavelength and a central wavelength is suppressed within the range of +&dgr;&lgr;/4.
    Type: Grant
    Filed: December 18, 1998
    Date of Patent: November 13, 2001
    Assignees: Kokusai Denshin Denwa Co., Ltd., Hitachi Cable Ltd.
    Inventors: Tetsuya Miyazaki, Shu Yamamoto, Koichi Maru, Hisato Uetsuka
  • Patent number: 6292603
    Abstract: A dispersion compensation device comprises a chirped grating, and a first optical unit for guiding at least a lightwave signal with a wavelength of &lgr;i that needs a positive dispersion compensation and is applied thereto to one end portion of the chirped grating whose grating pitch is shorter, and for furnishing light reflected by the chirped grating to outside the device. The device further comprises a second optical unit for guiding at least a lightwave signal with a wavelength of &lgr;i that needs a negative dispersion compensation and is applied thereto to another end portion of the chirped grating whose grating pitch is longer, and for furnishing light reflected by the chirped grating to outside the device. Both the first and second optical units can be either optical circulators or optical couplers.
    Type: Grant
    Filed: December 8, 1998
    Date of Patent: September 18, 2001
    Assignees: Kokusai Denshin Denwa Co., Ltd., Mitsubishi Denki Kabushiki Kaisha
    Inventors: Takashi Mizuochi, Tadayoshi Kitayama, Hideaki Tanaka, Koji Goto
  • Patent number: 6239834
    Abstract: An apparatus for evaluating digital picture quality, includes a SNR calculation module for calculating a SNR based upon differences between data of video picture to be evaluated and data of original video picture, a module for calculating a power of AC component of overall data of one of the video pictures in a frame, and a weighting module for weighting the calculated SNR based upon the calculated power of the AC component.
    Type: Grant
    Filed: January 2, 1997
    Date of Patent: May 29, 2001
    Assignee: Kokusai Denshin Denwa Co., Ltd.
    Inventors: Satoshi Miyaji, Takahiro Hamada, Shuichi Matsumoto
  • Patent number: 6236488
    Abstract: Detection of an optical pulse position uses an optical pulse string with a determined repetitive ratio and an electric clock signal with a same frequency as the repetitive ratio of the optical pulse string. A phase of the electric clock signal oscillator is shifted and supplied to an optical modulator. The optical modulator modulates the optical pulse string based on the electric clock signal and outputs a modulated optical signal. A photo detector converts the modulated optical signal output from the optical modulator to an electric signal. The phase shift amount of the electric clock signal is controlled to maximize an output from the photo detector. Additionally, a dither signal may be used in the control of the phase shift, more than the optical modulator may be employed, and/or more than color light source may be employed. The use of at least one of feed forward and feedback control provided by maximizing an output of the photo detector allows an optical pulse having a short width to be realized.
    Type: Grant
    Filed: March 31, 1998
    Date of Patent: May 22, 2001
    Assignees: Mitsubishi Denki Kabushiki Kaisha, Kokusai Denshin Denwa Co., Ltd
    Inventors: Katsuhiro Shimizu, Takashi Mizuochi, Takeshi Komiya, Kiwami Matsushita, Tadayoshi Kitayama, Masatoshi Suzuki, Hidenori Taga, Shu Yamamoto, Noboru Edagawa, Itsuro Morita
  • Patent number: 6178450
    Abstract: A method and apparatus for monitoring a communication link based on TCP/IP protocol obtains a protocol data unit (PDU) between communication systems. A emulation log is produced by analyzing the PDU in a PDU analysis part. An event sequence log is produced by estimating an event sequence of both communication systems based the emulation log in an event sequence estimation part. The behavior and the internal procedure of TCP is emulated by using the specific TCP state transition specification, internal variables of TCP, internal variables indicating the status and internal procedures in the TCP emulation part.
    Type: Grant
    Filed: July 1, 1998
    Date of Patent: January 23, 2001
    Assignee: Kokusai Denshin Denwa Co., Ltd.
    Inventors: Tomohiko Ogishi, Akira Idoue, Toshihiko Kato, Kenji Suzuki
  • Patent number: 6154506
    Abstract: A timing recovery and tracking method and apparatus with respect to data signal in a digital communication system is provided. The method includes a step of setting a time window for making a decision based upon a predetermined threshold level, the time window having a time period corresponding to a transmission data rate in the digital communication system, a step of detecting a time duration positioned within the time window, a level of a received signal being higher than the predetermined threshold level during the time duration, a step of assuming a substantially middle point of the time duration as an optimum decision point of the received signal, and a step of updating the time window so that the updated time window has its center at a position of the assumed optimum decision point.
    Type: Grant
    Filed: May 1, 1998
    Date of Patent: November 28, 2000
    Assignee: Kokusai Denshin Denwa Co., Ltd.
    Inventors: Hiroyasu Ishikawa, Hideyuki Shinonaga, Hideo Kobayashi
  • Patent number: 6147974
    Abstract: An apparatus for monitoring state of traffic in a telecommunication network by calculating ABR based upon BID and ANS per unit time in the network. This apparatus includes a model generation unit for receiving sampled data for generating models, the sampled data being constituted by a set of pairs of BID and ANS per unit time when the network is normal, and for calculating an average connection ratio when the network is normal based upon the sampled data, a calculation unit for calculating log-likelihood at a single point under hypothesizes of normality and degradation of the network based upon time series BID and ANS and upon the average connection ratio calculated by the model generation unit, and a detection unit for detecting whether state of traffic in the network is normal or degraded based upon time series log-likelihood of under hypothesizes of normality and degradation calculated by the calculation unit.
    Type: Grant
    Filed: February 27, 1998
    Date of Patent: November 14, 2000
    Assignee: Kokusai Denshin Denwa Co., Ltd.
    Inventors: Kazunori Matsumoto, Kazuo Hashimoto
  • Patent number: 6108380
    Abstract: When a selective decision of the field mode/frame mode for orthogonal transform is made for each macroblock composed of a plurality of blocks in a motion picture coding system wherein coding of an interlaced TV signal proceeds in the frame structure and an orthogonal transform is made in the unit of a block, the respective variances of the blocks within the macroblock are calculated, the calculated results are substituted respectively into an monotonously increasing and saturation tending nonlinear function to evaluate the sum of these functional values, and such a decision is made as to select the smaller mode in sum.
    Type: Grant
    Filed: October 27, 1997
    Date of Patent: August 22, 2000
    Assignee: Kokusai Denshin Denwa Co., Ltd.
    Inventors: Satoshi Miyaji, Shuichi Matsumoto
  • Patent number: 6107961
    Abstract: A map display system includes a plurality of geographic information servers, a geographic information search server and clients, connected to each other through network. The geographic information search server searches a plurality of geographic information servers and generates a combination list containing information of existential place of the plurality of geographic information servers. The clients obtain a plurality of geographic information from the plurality of geographic information servers designated by the combination list and display the obtained plurality of geographic information while superimposing them so that the coordinates thereof coincide each other on the same screen.
    Type: Grant
    Filed: February 24, 1998
    Date of Patent: August 22, 2000
    Assignee: Kokusai Denshin Denwa Co., Ltd.
    Inventor: Satoru Takagi
  • Patent number: 6104746
    Abstract: A combined channel or a composite channel is to be transformed into a plurality of element channels. The composite channel may be either shared by a plurality of communication stations on time division multiplex basis, or used by a single communication station. In a transmit side, a serial data information which is called a composite channel is transformed to parallel form associated with a plurality of element channels, each of which is spread by using a single common PN code. Each spread element channels are frequency converted to radio frequency so that the center carrier frequency is offset from that of adjacent element channel by an integer multiple of information transmission rate of each element channel, and frequency band occupied by spread element channels overlap with one another. Each element channels thus spread and frequency converted are combined on frequency axis, and transmitted to a receive side.
    Type: Grant
    Filed: September 8, 1997
    Date of Patent: August 15, 2000
    Assignee: Kokusai Denshin Denwa Co., Ltd.
    Inventors: Hiroyasu Ishikawa, Hideyuki Shinonaga, Hideo Kobayashi
  • Patent number: 6092113
    Abstract: An IP tunnel is constructed between routers connected with the INTERNET. A bandwidth of the IP tunnel is assured by setting up a reservation resource protocol (RSVP) on the IP tunnel. Further as a traffic control of the routers and on the IP tunnel, a frequency for sending packets, which are processed by an input processor and an output processor inside of the router, is allotted based on a ratio of the reserved bandwidth in each IP tunnel, then an algorithm for controlling the traffic is simplified. Furthermore each of the routers on the IP tunnel has a function for scheduling a reservation and manages a time period at which the virtual private network (VPN) of a type of the reservation resource protocol (RSVP) will be used, then it is possible to reserve the assurance of the bandwidth on the designated date and time in the future.
    Type: Grant
    Filed: August 28, 1997
    Date of Patent: July 18, 2000
    Assignee: Kokusai Denshin Denwa, Co., Ltd.
    Inventors: Osamu Maeshima, Yoshihiro Ito, Masami Ishikura, Tohru Asami
  • Patent number: 6081838
    Abstract: The managed object instance is used as access control unit, then access denial and permission are quickly decided. After a pre-process to the naming tree which is an object of access control, MOI included within every scope which can be designated by the management operation is obtained. At every issue of the management operation, access denial and permission are decided by using the data obtained in the pre-process. When the configuration of the naming tree is changed, the data are easily and rapidly revised, then the access control is adaptive to the dynamic change of the naming tree.
    Type: Grant
    Filed: March 5, 1998
    Date of Patent: June 27, 2000
    Assignee: Kokusai Denshin Denwa Co., Ltd.
    Inventors: Kiyohito Yoshihara, Hiroki Horiuchi, Keizo Sugiyama, Sadao Obana
  • Patent number: 6078913
    Abstract: A document retrieval apparatus is connected to a network, and includes a cluster database storing a cluster of node information elements linked for clustering the documents to a hierarchical tree structure based on degree of similarity in all of the documents. The apparatus can post to an end address in the node information element encountered on the way to follow links of the cluster by whenever one of the documents is updated. Also, the apparatus selects a specific number of documents, clusters those, assigns the remaining non-selected documents respectively to a leaf node to be similar to the documents in the cluster, and repeats recursively the above operations toward a direction of the leaf node of cluster.
    Type: Grant
    Filed: February 11, 1998
    Date of Patent: June 20, 2000
    Assignee: Kokusai Denshin Denwa Co., Ltd.
    Inventors: Keiko Aoki, Kazunori Matsumoto, Kazuo Hashimoto
  • Patent number: 6076164
    Abstract: A method and system for authenticating between a user or client and a network access entity such as a server or another client using an IC card. The method includes a step of executing an initial authentication using the IC card when the user first communicates with the network access entity, a step of commonly holding authentication information in both the user and the network access entity if the initial authentication achieves success, and a step of executing a re-authentication using the commonly held authentication information without using the IC card when the user communicates again with the same network access entity within a predetermined period of time after the last authentication.
    Type: Grant
    Filed: August 29, 1997
    Date of Patent: June 13, 2000
    Assignee: Kokusai Denshin Denwa Co., Ltd.
    Inventors: Toshiaki Tanaka, Satoshi Hada, Mitsuru Yamada
  • Patent number: 6061352
    Abstract: A cell disassemble circuit in a cell receiver system detects the number of lost cells from information for detecting cell loss included in received cells, and separates a payload from a header in each of the received cells. The number of lost cells indicates the number of cells lost on a transmission path from the transmission side to the cell receiver system. A buffer stores the number of detected lost cells and data inserted in the payloads. A phase locked loop recovers a source clock corresponding to the rate of fixed rate information based on a use level of the buffer. A counter circuit generates a clock for reading data from the first buffer from the recovered source clock. Also, the counter circuit stops outputting the read clock to the buffer for a time period corresponding to the number of lost cells.
    Type: Grant
    Filed: December 3, 1996
    Date of Patent: May 9, 2000
    Assignees: Matsushita Electric Industrial Co., Ltd., Kokusai Denshin Denwa Co., Ltd.
    Inventors: Katsuyuki Yamazaki, Shinobu Yagi, Akito Fukui