Patents by Inventor Kazuo Shirakawa

Kazuo Shirakawa 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: 7501959
    Abstract: A signal incoming direction estimation apparatus is constructed so as to comprise a sensor array having plural sensors and the impedance of each of the sensors being set to a predetermined value, respectively, and a variable impedance adjustment means having a variable impedance, being selectively connected to any one of the sensors of the sensor array, and controlling the current distribution of each of the above-mentioned sensors. Due to this, it becomes possible for the signal incoming direction estimation apparatus to carry out a beam scan only by manipulating at least one impedance without simultaneously manipulating all of the sensor impedances and thereby a high-speed beam scan (directional control) becomes possible.
    Type: Grant
    Filed: August 26, 2005
    Date of Patent: March 10, 2009
    Assignee: Fujitsu Limited
    Inventor: Kazuo Shirakawa
  • Publication number: 20080316090
    Abstract: A DSSS (Direct Sequence Spectrum Spreading) radar has a transmitting part to transmit a transmitting signal, including a predetermined code sequence, to one or a plurality of targets, a receiving part to receive a received signal corresponding to the transmitting signal which has been reflected from the one or a plurality of targets, and a computing part. The computing part computes a sum signal and a difference signal of received signals received by the receiving part at different points in time, and obtains a Doppler frequency of the one or a plurality of targets based on a phase difference between the sum signal and the difference signal.
    Type: Application
    Filed: March 13, 2008
    Publication date: December 25, 2008
    Inventor: Kazuo Shirakawa
  • Patent number: 7450056
    Abstract: The search/detection apparatus modulates a carrier signal by a modulation signal, generates a probe signal for detecting the location of a target, and receives the probe signal reflected by the target as an echo signal. Then, the search/detection apparatus detects the existence of an interference signal other than the echo signal from the received signal and modifies the parameter of the modulation signal and/or carrier signal.
    Type: Grant
    Filed: May 31, 2006
    Date of Patent: November 11, 2008
    Assignees: Fujitsu Limited, Fujitsu Ten Limited
    Inventors: Kazuo Shirakawa, Naofumi Ohkubo, Tetsuo Seki, Kanako Honda, Osamu Isaji
  • Publication number: 20080204306
    Abstract: A detecting and ranging apparatus and a program product obtain a correct relative velocity vector by a simple calculation based on a relative distance etc. obtained by a plurality of detectors such as a radar etc. by including: two relative distance measurement units receiving a reflected wave of a transmitted electromagnetic wave by an object to be detected, and thereby measuring a relative distance to the object to be detected, arranged at with each other different position; and an actual velocity vector calculation unit calculating an actual velocity vector of the object to be detected moving with an angle made in a direction from either relative distance measurement unit to the object to be detected based on the relative distances measured by the relative distance measurement units.
    Type: Application
    Filed: December 13, 2007
    Publication date: August 28, 2008
    Inventor: Kazuo Shirakawa
  • Publication number: 20080169966
    Abstract: An on-vehicle radar device has a transmission section for transmitting a radio wave to an object, a receive section for receiving the radio wave reflected by the object, and a processing section for dividing an object detection range into three or more of a plurality of areas, setting a threshold of an intensity of the radio wave received for each of the plurality of areas, and judging the existence of an object by comparing the intensity of the radio wave and the threshold. This processing section sets, based on an auto-cruise control mode or pre-crash mode of the vehicle, a threshold of a part of an area in the object detection range to be lower than the threshold of the other areas, or changes the threshold of the detection area according to the object detection status.
    Type: Application
    Filed: August 3, 2007
    Publication date: July 17, 2008
    Applicants: FUJITSU TEN LIMITED, FUJITSU LIMITED
    Inventors: Masataka Tsuchihashi, Nobukazu Shima, Kazuo Shirakawa
  • Publication number: 20080136702
    Abstract: A radar device has a long range radar sensor having a first transmission and receiving section for transmitting and receiving radio wave to a first detection range and a first signal processing section for detecting an object existing in the first detection range; a short range radar sensor having a second transmission and receiving section for transmitting and receiving a radio wave to a second detection range of which width is wider and of which distance is shorter than the first detection range and a second signal processing section for detecting an object existing in the second detection range; and a processing section for integrating information supplied from the first and second signal processing sections. And one of the long range radar sensor and the short range radar sensor stops a detection operation of the object to an overlapped range of both the detection ranges.
    Type: Application
    Filed: July 20, 2007
    Publication date: June 12, 2008
    Applicants: FUJITSU TEN LIMITED, FUJITSU LIMITED
    Inventors: Masataka Tsuchihashi, Nobukazu Shima, Kazuo Shirakawa
  • Publication number: 20080122681
    Abstract: An arriving direction estimating device for estimating the arriving direction of an arriving wave with high accuracy and at high speed by using a sensor array. The arriving direction estimating device comprises a receiving section for generating a baseband signal from the arriving signals received by sensors, a matrix creating section for creating a spatial average covariance matrix R by combining the correlation vector of the baseband signal, a projection matrix creating section for creating a projection matrix Q from the matrix R depending on the number of signals of the arriving signals, a scale matrix creating section for creating a scale matrix S from a partial matrix of the matrix R, and an estimating section for estimating the arriving direction of the arriving wave from the angle distribution or an algebraic equation by using QS?1QH defined using the projection matrix Q and the scale matrix S.
    Type: Application
    Filed: June 19, 2007
    Publication date: May 29, 2008
    Inventor: Kazuo Shirakawa
  • Patent number: 7379020
    Abstract: A radio wave direction-of-arrival estimation apparatus and method that can estimate, at high speed and with good accuracy, the direction of arrival of a plurality of incoming waves having high correlation.
    Type: Grant
    Filed: March 10, 2006
    Date of Patent: May 27, 2008
    Assignee: Fujitsu Limited
    Inventors: Masataka Tsuchihashi, Yasushi Seike, Kazuo Shirakawa, Jingmin Xin
  • Publication number: 20080106458
    Abstract: Provide an on-vehicle radar device that performs transmission control of a monitoring signal, following fixed rules, so that interference with other radar devices can be avoided with certainty. An on-vehicle radar device comprises a transceiver which transmits/receives a monitoring signal at a specified frequency band and transmits a priority order signal at a frequency within the above-mentioned frequency band, and a controller which switches the signals transmitted by the transceiver. The transceiver receives a priority order signal of another radar device, and when interference with the signal of the other radar device is detected, the controller, based on the priority order of that other device and on the priority order of the device itself, shifts, by a specified frequency amount, the frequency band of the monitoring signal transmitted by the transceiver.
    Type: Application
    Filed: March 30, 2007
    Publication date: May 8, 2008
    Applicants: FUJITSU TEN LIMITED, FUJITSU LIMITED
    Inventors: Kanako Honda, Osamu Isaji, Kazuo Shirakawa, Naofumi Ohkubo, Tetsuo Seki
  • Publication number: 20080024352
    Abstract: A wide monitor area can be covered by switching the connection between a plurality of sensors and a transmission/reception device using a switch device of a target detection apparatus in a time division manner. When only two target detection apparatuses are used in positioning a target, the position of a target can be identified according to the information about an area common to both angle ranges covered by the two apparatuses or the total propagation distance information from one apparatus to the other apparatus through each target.
    Type: Application
    Filed: January 26, 2007
    Publication date: January 31, 2008
    Inventor: Kazuo Shirakawa
  • Publication number: 20080007455
    Abstract: An incoming direction estimation apparatus estimates an incoming direction of a radar wave using three or more sensors or antennas simultaneously. An arithmetic expression for estimating an incoming direction of a radar wave is configured as sin?1((½?a)*tan?1b). The “a” is d/? determined by an antenna interval and by a wavelength ? of a carrier, or such, carrying the radar wave. A simultaneous use of three antennas makes it possible to set the a as a value depending on a value d0=a0? based on the interval between first antennas and value d1=a1? based on the interval between second antennas. Therefore, if a wide field of vision of an incoming direction is needed, it is only necessary to adjust (d1?d0)/?=(a1?a0), in place of the absolute interval of antennas a=d/?, thereby making it possible to lessen a limitation on the design of antennas and set a field of vision of the incoming direction appropriately.
    Type: Application
    Filed: August 17, 2007
    Publication date: January 10, 2008
    Applicant: FUJITSU LIMITED
    Inventor: Kazuo Shirakawa
  • Publication number: 20070188373
    Abstract: The search/detection apparatus modulates a carrier signal by a modulation signal, generates a probe signal for detecting the location of a target, and receives the probe signal reflected by the target as an echo signal. Then, the search/detection apparatus detects the existence of an interference signal other than the echo signal from the received signal and modifies the parameter of the modulation signal and/or carrier signal.
    Type: Application
    Filed: May 31, 2006
    Publication date: August 16, 2007
    Applicants: Fujitsu Limited, Fujitsu Ten Limited
    Inventors: Kazuo SHIRAKAWA, Naofumi Ohkubo, Tetsuo Seki, Kanako Honda, Osamu Isaji
  • Publication number: 20070176822
    Abstract: A wide monitor area can be covered by switching the connection between a plurality of sensors and a transmission/reception device using a switch device of a target detection apparatus in a time division manner. When only two target detection apparatuses are used in positioning a target, the position of a target can be identified according to the information about an area common to both angle ranges covered by the two apparatuses or the total propagation distance information from one apparatus to the other apparatus through each target.
    Type: Application
    Filed: April 7, 2006
    Publication date: August 2, 2007
    Inventor: Kazuo Shirakawa
  • Patent number: 7196656
    Abstract: An apparatus for estimating direction of arrival of signal is provided that has excellent performance in terms of angular resolution and the number of signals that can be identified. In an array sensor comprising a plurality of sensor elements, the two outermost sensor elements are alternately selected by a switch for use as a transmitting sensor, and the other sensor elements are selected in time division fashion as receiving sensors. With this arrangement, the effective aperture is increased to about twice the physical aperture, to improve angular resolution in a direction-of-arrival estimator.
    Type: Grant
    Filed: December 21, 2004
    Date of Patent: March 27, 2007
    Assignee: Fujitsu Limited
    Inventor: Kazuo Shirakawa
  • Publication number: 20060261968
    Abstract: A signal incoming direction estimation apparatus is constructed so as to comprise a sensor array having plural sensors and the impedance of each of the sensors being set to a predetermined value, respectively, and a variable impedance adjustment means having a variable impedance, being selectively connected to any one of the sensors of the sensor array, and controlling the current distribution of each of the above-mentioned sensors. Due to this, it becomes possible for the signal incoming direction estimation apparatus to carry out a beam scan only by manipulating at least one impedance without simultaneously manipulating all of the sensor impedances and thereby a high-speed beam scan (directional control) becomes possible.
    Type: Application
    Filed: August 26, 2005
    Publication date: November 23, 2006
    Inventor: Kazuo Shirakawa
  • Publication number: 20060208947
    Abstract: A radio wave direction-of-arrival estimation apparatus and method that can estimate, at high speed and with good accuracy, the direction of arrival of a plurality of incoming waves having high correlation.
    Type: Application
    Filed: March 10, 2006
    Publication date: September 21, 2006
    Inventors: Masataka Tsuchihashi, Yasushi Seike, Kazuo Shirakawa, Jingmin Xin
  • Publication number: 20060066474
    Abstract: An apparatus for estimating direction of arrival of signal is provided that has excellent performance in terms of angular resolution and the number of signals that can be identified. In an array sensor comprising a plurality of sensor elements, the two outermost sensor elements are alternately selected by a switch for use as a transmitting sensor, and the other sensor elements are selected in time division fashion as receiving sensors. With this arrangement, the effective aperture is increased to about twice the physical aperture, to improve angular resolution in a direction-of-arrival estimator.
    Type: Application
    Filed: December 21, 2004
    Publication date: March 30, 2006
    Inventor: Kazuo Shirakawa
  • Patent number: 5100498
    Abstract: A patterned structure including a plurality of patterned sheet members which have respective configurations and which are partially superposed on each other and which cooperate with each other to define a plurality of voids. At least one of the sheet members includes a thin-walled portion whose thickness is smaller than a thickness of the other portion. The thin-walled portion is formed by etching the appropriate sheet member or members. The thin-walled portion of one sheet member engages the corresponding thin-walled portion or the other portion of the other sheet member or members.
    Type: Grant
    Filed: March 1, 1991
    Date of Patent: March 31, 1992
    Assignees: NGK Insulators, Ltd., Toppan Printing Co., Ltd.
    Inventors: Yukihisa Takeuchi, Tetsuo Watanabe, Azuma Yamamoto, Kazuo Shirakawa, Takao Segawa
  • Patent number: 5023700
    Abstract: A patterned structure including a plurality of patterned sheet members which have respective configurations and which are partially superposed on each other and which cooperate with each other to define a plurality of voids. At least one of the sheet members includes a thin-walled portion whose thickness is smaller than a thickness of the other portion. The thin-walled portion is formed by etching the appropriate sheet member or members. The thin-walled portion of one sheet member engages the corresponding thin-walled portion or the other portion of the other sheet member or members.
    Type: Grant
    Filed: June 16, 1989
    Date of Patent: June 11, 1991
    Assignees: NGK Insulators, Ltd., Toppan Printing Co., Ltd.
    Inventors: Yukihisa Takeuchi, Tetsuo Watanabe, Azuma Yamamoto, Kazuo Shirakawa, Takao Segawa
  • Patent number: 4433043
    Abstract: A water based photosensitive composition comprises a hydrolyzate of a mammal collagen and a photosensitizer serving to cross-link the hydrolyzate when exposed to an active light. The hydrolyzate has a number-average molecular weight, Mn, of 2,000 to 30,000 and an intrinsic viscosity, [.eta.], of 0.060 to 0.155 dl/g in a 0.15 mole citric acid buffer solution maintained at 40.degree.C. Also, the hydrolyzate is capable of maintaining the formability of the collagen fold. A photoresist pattern formed by using the composition exhibits a high resolution, a good dyeing property and a strong corrosion resistance.
    Type: Grant
    Filed: November 13, 1981
    Date of Patent: February 21, 1984
    Assignees: Toppan Printing Co., Ltd., Nippi, Inc.
    Inventors: Yoshikatu Sawada, Kazuo Shirakawa, Takeo Sugiura