Patents Assigned to Kokusai Denshin Denwa Kabushiki Kaisha
  • Patent number: 6134523
    Abstract: Coding bit rate converting method and apparatus for coded audio data are disclosed to convert input coded audio data to output coded data of a coding bit rate lower than a target coding bit rate. A control output is taken out when the frame size of the input coded audio data is larger than the frame size determined by the target coding bit rate, and the output coded data is provided as a converted output by controlling parameters defining the frame size of the input coded audio data by the use of the control output in a predetermined procedure until the frame size of the input coded audio data becomes smaller than the frame size determined by the target coding bit rate.
    Type: Grant
    Filed: December 10, 1997
    Date of Patent: October 17, 2000
    Assignee: Kokusai Denshin Denwa Kabushiki Kaisha
    Inventors: Yasuyuki Nakajima, Kiyono Ujihara, Akio Yoneyama
  • Patent number: 6111937
    Abstract: This invention is characterized by providing an apparatus for automatically discriminating service users which can prevent troubles from occurring between the service provider and users because of difference in language. When the service provider has a call from a user, the service provider makes an announcement to the user to request the voicing of a specific keyword. If an answer by the keyword is made from the user, it is determined whether or not it is an answer by the correct keyword. If correct, the call is connected to the service provider. If not correct, how to use the service is announced in another language. Then, the line is disconnected. As a result, a user who is weak in the language used by the service provider can be prevented from being connected to the service provider.
    Type: Grant
    Filed: July 14, 1997
    Date of Patent: August 29, 2000
    Assignee: Kokusai Denshin Denwa Kabushiki Kaisha
    Inventors: Shingo Kuroiwa, Shin-ichi Sakayori, Seiichi Yamamoto, Masanobu Fujioka
  • Patent number: 6091538
    Abstract: An equalizing apparatus for equalizing gains of wideband wavelength-division multiplexed light and for improving the S/N ratio comprises a plurality of optical amplifyer for optically amplifying light in different wavelength groups, respectively; and multiplexer for multiplexing optically amplified light from said plurality of optically amplifying means.
    Type: Grant
    Filed: December 9, 1997
    Date of Patent: July 18, 2000
    Assignee: Kokusai Denshin Denwa Kabushiki Kaisha
    Inventors: Noriyuki Takeda, Shigeyuki Akiba, Noboru Edagawa, Hidenori Taga
  • Patent number: 6088383
    Abstract: A spread spectrum signal demodulator receives a received signal including a plurality of spread spectrum signals, and comprises at least one signal strength suppressing means, which reduces a correlation signal outputted from a first correlation detecting means or replica signals until the correlation signal has been traveled through a replica signal generating means, a replica signal subtracting means and a second correlation detecting means. According to the invention, it is possible to improve interference cancellation capacity with a computational effort substantially comparable to that in a prior art replica signal cancellation system and improve interference cancellation performance with increasing number of interference cancellers irrespective of the magnitude of the correlation. With a sufficient number of interference cancellers provided, it is possible to obtain the same effect as obtainable with prior art decorrelation in a real time processing irrespective of the correlation magnitude.
    Type: Grant
    Filed: October 15, 1997
    Date of Patent: July 11, 2000
    Assignee: Kokusai Denshin Denwa Kabushiki Kaisha
    Inventors: Toshinori Suzuki, Yoshio Takeuchi
  • Patent number: 6084997
    Abstract: The coupled waveguide structure comprises first and second rectangular waveguides, disposed closely. The aspect ratio of the first waveguide is substantially inverse in number to that of the second waveguide.
    Type: Grant
    Filed: June 22, 1998
    Date of Patent: July 4, 2000
    Assignee: Kokusai Denshin Denwa Kabushiki Kaisha
    Inventors: Katsuyuki Utaka, Shinsuke Tanaka, Masayoshi Horita, Yuichi Matsushima
  • Patent number: 6052734
    Abstract: An amount of data to be distributed to each receiving terminal is dynamically controlled for each receiving terminal in response to a congestion of each of plural receiving terminals. When a determination of an RR (Reception Report) returned from the receiving terminal results in a very low rate of packet loss, an adaptive control mixer distributes communication data transmitted from a transmitting terminal to the receiving terminal without reducing the communication data. On the other hand, the determination of the RRs returned from the receiving terminals results in a high rate of packet loss, for example, 50% and 90%, respectively. In this case, the adaptive control mixer reduces, for example, 50% of the communication data transmitted from the transmitting terminal and then distributes the data to the one receiving terminal. The adaptive control mixer reduces, for example, 90% of the communication data and then distributes the data to the other receiving terminal.
    Type: Grant
    Filed: February 17, 1998
    Date of Patent: April 18, 2000
    Assignee: Kokusai Denshin Denwa Kabushiki Kaisha
    Inventors: Yoshihiro Ito, Hidetoshi Yokota, Masami Ishikura, Tooru Asami
  • Patent number: 6037612
    Abstract: At least a one conductivity type nanostructure PS layer whose thickness is controlled, and the opposite conductivity type nanostructure PS layer and a one conductivity type mesostructure PS layer arranged in contact with both these sides are comprised. Since the one conductivity type nanostructure PS layer is formed by anodizing the non-degenerate n-type crystalline silicon layer whose thickness is established in advance, the thickness which can provides a maximum luminescence efficiency can be obtained correctly. Then a semiconductor light emitting device whose luminescence efficiency is improved without increasing an unnecessary series resistance is provided.
    Type: Grant
    Filed: September 9, 1998
    Date of Patent: March 14, 2000
    Assignee: Kokusai Denshin Denwa Kabushiki Kaisha
    Inventors: Kohsuke Nishimura, Yasuyuki Nagao
  • Patent number: 6025879
    Abstract: A system for detecting a moving object in a moving picture, which can detect a moving object by block directly with a highly-accurate, simple process without completely decoding the compressed moving picture data. The picture block coding mode, the motion compensation mode and the motion vector information (information b) decoded in a variable-length decoder 1 and the texture information d detected by a texture information detector 7 are applied to a moving object detection processor 8. The moving object detection processor 8 judges whether the particular block is a moving object or not using the information b or the combined information b and the texture information d. This judgement is effected by a motion vector, a spatial similarity judgement and a temporal similarity judgement. The moving object detection information e resulting from the judgement is sent to a picture image processor 5 for processing the picture information f.
    Type: Grant
    Filed: August 11, 1997
    Date of Patent: February 15, 2000
    Assignee: Kokusai Denshin Denwa Kabushiki Kaisha
    Inventors: Akio Yoneyama, Yasuyuki Nakajima, Kiyono Ujihara
  • Patent number: 6026389
    Abstract: A video query and editing system which is capable of querying images without fast-forward and playback operations, to specify an editing start or end point easily, and to lower editing cost of compressed data. An edit control window is displayed (11) first, and then a file for query and editing is selected in query and editing file processing 12. In motion picture query processing 13, image query is performed in macro or micro units for the selected file and then the images to be under the query and editing are displayed. In editing section specification 14, a start point and an end point of a section for the editing are specified out of the images displayed in the motion picture query processing. Editing of a plurality of sections or other files are performed in the same manner as for the above processing if desired. After all the editing sections are determined, the editing sections are played back in editing section playback 17 to confirm the editing parts.
    Type: Grant
    Filed: August 4, 1997
    Date of Patent: February 15, 2000
    Assignee: Kokusai, Denshin, Denwa, Kabushiki Kaisha
    Inventors: Yasuyuki Nakajima, Kiyono Ujihara, Akio Yoneyama
  • Patent number: 6021235
    Abstract: A new two-way WDM optical transmission system is provided. The WDM optical transmission system comprises a two-way optical fiber cable, a first dispersion compensation optical fiber (DCOF) connected to one end of the optical fiber cable, a second DCOF connected to another end of the optical fiber cable, a chromatic dispersion compensating transmitter unit and a chromatic dispersion compensating receiver unit. The two-way optical fiber cable comprises a plurality of segments. The first DCOF is connected to one end of the optical fiber cable and has a compensation amount of a half of a one segment dispersion D.sub.c of the optical fiber cable. The second DCOF is connected to another end of the optical fiber cable and has the compensation amount of the half of the one segment dispersion D.sub.c. And the chromatic dispersion compensating transmitter unit compensates accumulated residual chromatic dispersions to be caused by higher-order wavelength dispersion of the optical fiber cable at each signal wavelength.
    Type: Grant
    Filed: July 31, 1998
    Date of Patent: February 1, 2000
    Assignee: Kokusai Denshin Denwa Kabushiki-Kaisha
    Inventors: Shu Yamamoto, Hidenori Taga, Masatoshi Suzuki, Noboru Edagawa, Shigeyuki Akiba
  • Patent number: 6011587
    Abstract: An H. 261 encoder outputs coded video data together with a mode selection signal and a judging signal as to discarding or not of a packet. A packetizer receives the output signal from the H. 261 encoder and separately packetizes motion data and DCT data in the input coded data. A gateway judges whether packet including the DCT data is discarded or not with reference to the packet discarding judging signal and also to the bitrate of the network to which the gateway is connected. The gateway thus can effect bitrate conversion according to the bitrate of the network with a simple construction. The gateway may selectively discard high frequency component packets without discarding low frequency component packets, or it may not discard first importance component packets having greater influence on picture quality and selectively discard second importance component packets having less influence.
    Type: Grant
    Filed: February 14, 1997
    Date of Patent: January 4, 2000
    Assignee: Kokusai Denshin Denwa Kabushiki Kaisha
    Inventors: Shigeyuki Sakazawa, Yasuhiro Takishima, Masahiro Wada
  • Patent number: 6005702
    Abstract: An optical transmission device using return-to-zero optical pulses as transmission optical pulses, which is capable of enhancing a transmission distance as well as a wavelength range with satisfactory transmission characteristics and enabling an easy realization of the wavelength division multiplexing optical transmission. The optical transmission device is formed by an optical transmitter for transmitting transmission optical pulses by superposing digital data signals onto return-to-zero optical pulses, and a modulator for applying one of a phase modulation and a frequency modulation in synchronization with a transmission rate of the transmission optical pulses, to the transmission optical pulses transmitted by the optical transmitter. This optical transmission device can be utilized in forming a wavelength division multiplexing optical transmission apparatus and an optical transmission system.
    Type: Grant
    Filed: February 19, 1997
    Date of Patent: December 21, 1999
    Assignee: Kokusai Denshin Denwa Kabushiki-Kaisha
    Inventors: Masatoshi Suzuki, Itsuro Morita, Noboru Edagawa, Shu Yamamoto, Shigeyuki Akiba
  • Patent number: 5978529
    Abstract: This invention provides the gain equalizer positioned to an optical amplifying transmission line for equalizing gains of said optical amplifying transmission line, comprising a plurality of first optical filters varying transmittance periodically in at least predetermined wavelength range, and one or more second optical filters that their transmittance peaks at a wavelength substantially coinciding to the predetermined transmittance bottom wavelength of the first optical filters and decreases in a predetermined range at both side of the predetermined transmittance bottom wavelength.
    Type: Grant
    Filed: March 6, 1998
    Date of Patent: November 2, 1999
    Assignee: Kokusai Denshin Denwa Kabushiki Kaisha
    Inventors: Hidenori Taga, Noriyuki Takeda, Masatoshi Suzuki, Shu Yamamoto, Shigeyuki Akiba
  • Patent number: 5978122
    Abstract: A method of suppressing noise and improving the optical transmission characteristic of a wavelength division multiplexing transmission system provides lights for suppressing noise from the light sources (NS1 and NS2) which are multiplexed on the wavelength division multiplexed signal. Consequently, the S/N ratio of each channel of a wavelength division multiplexed signal which propagates through the optical path can be improved.
    Type: Grant
    Filed: June 26, 1996
    Date of Patent: November 2, 1999
    Assignee: Kokusai Denshin Denwa Kabushiki Kaisha
    Inventors: Toshio Kawazawa, Koji Goto, Tomohiro Otani, Haruo Abe, Masando Tanaka
  • Patent number: 5969669
    Abstract: A method is disclosed for uniquely determining the position of a mobile earth station in a mobile satellite communication system which employs a non-geostationary satellite with a multi-spot beams. A given point of a preknown position on the earth surface is defined as the center coordinate of a three-dimensional coordinate axis, information on the measured distance and Doppler shift amount between a mobile earth station of an unknown position and a non-geostationary satellite is used to repeat the estimation of the position of the mobile earth station a plurality of times, thereby obtaining the position of the earth station with high accuracy.
    Type: Grant
    Filed: December 4, 1995
    Date of Patent: October 19, 1999
    Assignee: Kokusai Denshin Denwa Kabushiki Kaisha
    Inventors: Hiroyasu Ishikawa, Hideyuki Shinonaga, Hideo Kobayashi
  • Patent number: 5966228
    Abstract: An optical transmission system comprises transmission optical fibers 14 connected between an optical transmission terminal 10 and an optical receiving terminal 12 via optical amplifying repeaters 16, and equalizing fiber 18 each connected in each equalizing interval. The equalizing fiber 18 is typically located at the terminal end of each equalizing interval. Each transmission optical fiber 14 is a dispersion-shifted fiber whose wavelength dispersion is substantially zero in a specific band, for example, 1.5 .mu.m. The optical amplifying repeaters 16 include an optical amplifier, and a dispersion compensating optical element having wavelength dispersion characteristics that exhibit an inclination opposite from that of wavelength characteristics of wavelength dispersion of the transmission optical fiber 14 (more specifically, a minus inclination with respect to the wavelength). The dispersion compensating optical element compensates offset values of cumulative wavelength dispersion among different wavelengths.
    Type: Grant
    Filed: November 26, 1996
    Date of Patent: October 12, 1999
    Assignee: Kokusai Denshin Denwa Kabushiki Kaisha
    Inventors: Shigeyuki Akiba, Shu Yamamoto, Masatoshi Suzuki, Noboru Edagawa, Hidenori Taga
  • Patent number: 5960063
    Abstract: A telephone speech recognition system is provided which has a high level of speech recognition without affecting from various conditions of a telephone line. The system comprises speech analyzers (4) and (5), and reference speech model storages (7) to (9) corresponding to line connection data. A telephone line interface (1) having a line connection data acquisition function analyzes a call received from the telephone line for identifying the country, route, and other information of the call and transmits those line connection data to a line connection data processor (2). The line connection data processor (2) selects one of the acoustic analyzers (4) and (5) in response to the line connection data from the interface (1) and also one of the speech model storages (7) to (9). A speech pattern matcher (11) compares an acoustic vector train output of the selected acoustic analyzer with the speech models given from the selected reference speech model storage for speech recognition.
    Type: Grant
    Filed: July 14, 1997
    Date of Patent: September 28, 1999
    Assignee: Kokusai Denshin Denwa Kabushiki Kaisha
    Inventors: Shingo Kuroiwa, Masaki Naito, Seiichi Yamamoto, Shin-ichi Sakayori, Masanobu Fujioka
  • Patent number: 5959764
    Abstract: A waveform converter includes a transmission-type InGaAsP electroabsorption optical modulator 10 using the Franz-Keldysh effect. Continuous light (probe light) 12 as a target of wavelength conversion is fed to an end surface 10a of the optical modulator 10 while a constant voltage of 3 V is applied to the optical modulator 10. An optical circulator 14 is supplied with original signal light (signal light to be waveform-converted) 16 through its terminal A, and delivers it from the terminal B thereof to another end surface 10b of the optical modulator 10. The optical modulator 10 gives a loss to the probe light 12 according to the intensity of the original signal light 16 and makes the waveform of the probe light 12 to be substantially the same as the original signal light. The probe light waveform-converted by the optical modulator 10 and output from the end surface 10b is fed to a terminal B of an optical circulator 14 as a waveform-converted light 18 and output from its terminal C.
    Type: Grant
    Filed: September 4, 1997
    Date of Patent: September 28, 1999
    Assignee: Kokusai Denshin Denwa Kabushiki Kaisha
    Inventors: Noboru Edagawa, Masatoshi Suzuki, Shu Yamamoto
  • Patent number: 5952683
    Abstract: A functional semiconductor element, which is designed to perform an ultrafast amplifying, bistable, similar functional operation by initiating and stopping an avalanche multiplication in one of i-type layers of what is called a triangular barrier diode (TBD) structure having an n-i-p-i-n, p-i-n-i-p, n-i-p-i-p, n-i-n-i-p, n-i-n-i-n, p-i-n-i-n, p-i-p-i-p, or p-i-p-i-n configuration. By forming a light absorbing layer and a light emitting layer or light modulating layer in this structure, it is possible to function the element as an optical functional element. Furthermore, the addition of a resonant tunneling diode implements a novel function.
    Type: Grant
    Filed: July 15, 1997
    Date of Patent: September 14, 1999
    Assignee: Kokusai Denshin Denwa Kabushiki Kaisha
    Inventors: Haruhisa Sakata, Katsuyuki Utaka, Yuichi Matsushima
  • Patent number: 5940197
    Abstract: The self-oscillation frequencies of injection-locked laser devices 5-1 through 5-M are preset to the frequency of the signal light to be transmitted by the optical add-drop device, and the self-oscillation frequencies of the injection-locked laser devices 6-1 through 6-N are preset to the frequency of the signal light to be branched by this device. Wavelength-division multiplexed signal light inputted from an input optical line 1 is split in an optical splitter 2 and inputted to the injection-locked laser devices. Signal light whose wavelength has been set for the injection-locked laser devices 5-1 through 5-M is amplified by these injection-locked laser devices 5-1 through 5-M and inputted to an optical combiner 10. Signal light whose wavelength has been set for the injection-locked laser devices 6-1 through 6-N is outputted to branching optical lines 8-1 through 8-N.
    Type: Grant
    Filed: March 27, 1997
    Date of Patent: August 17, 1999
    Assignee: Kokusai Denshin Denwa Kabushiki Kaisha
    Inventor: Shiro Ryu