Patents by Inventor Katsuhiro Morikawa

Katsuhiro Morikawa 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).

  • Publication number: 20030197498
    Abstract: In a shift clock signal generating apparatus, a delay line includes a plurality of unit delay elements connected in cascade. A reference clock signal propagates in the delay line while being successively delayed by the unit delay elements. Switches have first ends connected with output terminals of the unit delay elements respectively, and second ends connected with a shift clock signal output path. When specified one among the switches is in its on position, a delayed clock signal which results from delaying the reference clock signal by a prescribed time interval is transmitted via the specified switch to the shift clock signal output path as a shift clock signal. The specified one among the switches is determined on the basis of data representing a phase difference of the shift clock signal from the reference clock signal. The specified switch is set in its on position.
    Type: Application
    Filed: April 25, 2003
    Publication date: October 23, 2003
    Inventors: Takamoto Watanabe, Katsuhiro Morikawa
  • Patent number: 6628374
    Abstract: A code generating device operates for generating a pseudo random noise code having a sequence of a predetermined number of chips each being in one of first and second logic states different from one another. A code monitoring device operates for detecting at least a preset number of successive chips in the first logic state in the pseudo random noise, and for changing at least one among the detected preset number of successive chips to the second logic state to convert the pseudo random noise code into a transmission signal. A driving device operates for activating and deactivating an electromagnetic wave generating device in response to the transmission signal. A receiving device operates for receiving an echo wave caused by reflection of an electromagnetic wave generated by the electromagnetic wave generating device at an object. A distance to the object is detected on the basis of the received echo wave.
    Type: Grant
    Filed: May 3, 2002
    Date of Patent: September 30, 2003
    Assignee: Denso Corporation
    Inventors: Noriaki Shirai, Katsuhiro Morikawa
  • Publication number: 20030103197
    Abstract: A method and apparatus of measuring a distance to a reflection object is disclosed. A sensitivity time control (STC) process is applied to a received signal from the reflection object to provide an STC-processed signal. The radar apparatus includes a controller. The controller obtains a quantity corresponding to the distance from a transmission time of the transmission signal and a detection time of the STC-processed signal. The quantity is corrected by using a first correction value associated with the intensity of the STC-processed reflection signal to provide a corrected quantity. The corrected quantity is further corrected by using a second correction value associated with the corrected quantity and the intensity of the STC-processed reflection signal to correct the error regardless of the intensity of the STC-processed reflection signal.
    Type: Application
    Filed: November 14, 2002
    Publication date: June 5, 2003
    Inventors: Noriaki Shirai, Katsuhiro Morikawa, Yoshie Samukawa, Keiji Matsuoka, Toyohito Nozawa
  • Patent number: 6567039
    Abstract: A radar device operates for emitting a detection wave ahead of a vehicle, and detecting objects in response to echoes of the emitted detection wave. A reflector detecting device operates for detecting reflectors among the objects detected by the radar device. The detected reflectors are located along a road. A reflector-row extracting device operates for, in cases where there are a plurality of rows of the reflectors detected by the reflector detecting device in one side of the vehicle, extracting one from among the reflector rows. A road-shape recognizing device operates for recognizing a shape of the road on the basis of the reflector row extracted by the reflector-row extracting device.
    Type: Grant
    Filed: April 25, 2001
    Date of Patent: May 20, 2003
    Assignee: Denso Corporation
    Inventors: Noriaki Shirai, Katsuhiro Morikawa
  • Patent number: 6553282
    Abstract: A transmission wave is applied to a predetermined angular range in a width-wise direction of a vehicle. A position of each object and a relative speed of the object are detected on the basis of the reflected wave. A determination is made as to whether each object is moving or stationary on the basis of the detected relative speed of the object and a speed of the vehicle. For at least one of right-hand and left-hand sides of the vehicle, calculation is given of a vehicle width-wise direction position where each stationary object effective for road shape recognition passes through the related side of the vehicle. The calculated vehicle width-wise direction position is memorized. A line connecting the memorized vehicle width-wise direction position and the detected position of the currently handled object corresponding to the effective stationary object is recognized as a road edge.
    Type: Grant
    Filed: February 23, 2001
    Date of Patent: April 22, 2003
    Assignee: Denso Corporation
    Inventors: Noriaki Shirai, Katsuhiro Morikawa
  • Patent number: 6553283
    Abstract: A transmission wave is applied to a predetermined angular range in a width-wise direction of a vehicle. Object-unit data pieces containing at least data pieces representing distances to objects in correspondence with vehicle-width-wise direction angles are generated on the basis of a reflected wave. A determination is made as to whether each object is moving or stationary on the basis of a speed of the vehicle and a relative speed of the object. From the object-unit data pieces, ones are extracted which are effective for road shape recognition on the basis of a result of determining whether each object is moving or stationary. Ones of the extracted object-unit data pieces which represent monotonically increasing distances as viewed along one of clockwise and counterclockwise angle directions are grouped to generate data representing a road-side-object group. A road edge is recognized on the basis of the data representing the road-side-object group.
    Type: Grant
    Filed: February 27, 2001
    Date of Patent: April 22, 2003
    Assignee: Denso Corporation
    Inventors: Noriaki Shirai, Katsuhiro Morikawa
  • Publication number: 20020186362
    Abstract: A forward electromagnetic wave is generated in accordance with a succession of pseudo random noise code signals. An echo electromagnetic wave caused by reflection of the forward electromagnetic wave at an object is converted into a received signal. Direct-current and low-frequency components are removed from the received signal to generate a filtering-resultant signal. The filtering-resultant signal is compared with a preset decision reference voltage to generate a binary signal. The binary signal is sampled into received data. Calculation is made as to a correlation between the received data and the pseudo random noise code signal. The distance to the object is computed on the basis of the calculated correlation. The pseudo random noise code signal is repetitively generated to produce a succession of the pseudo random noise code signals during a surplus time covering a stabilization time taken by the received signal to stabilize in direct-current voltage level.
    Type: Application
    Filed: May 30, 2002
    Publication date: December 12, 2002
    Inventors: Noriaki Shirai, Katsuhiro Morikawa
  • Patent number: 6484087
    Abstract: The radius of the curvature of the lane on which a subject vehicle is traveling, is calculated in accordance with the turning condition of the subject vehicle and the velocity of the subject vehicle is obtained on the basis of the steering angle, and the yaw rate. An instantaneous probability of the same lane that the recognized object target exists on the same lane is calculated. In this operation, the instantaneous probability is compensated. That is, the road shape is recognized with delineator or the like. The instantaneous probability of the same lane is compensated on the basis of the recognized road shape. The probability of the same lane is calculated after a predetermined filtering process with the compensated instantaneous probability of the same lane. The preceding vehicle is selected on the basis of the probability of the same lane.
    Type: Grant
    Filed: March 26, 2001
    Date of Patent: November 19, 2002
    Assignee: Denso Corporation
    Inventors: Noriaki Shirai, Katsuhiro Morikawa
  • Publication number: 20020167654
    Abstract: A code generating device operates for generating a pseudo random noise code having a sequence of a predetermined number of chips each being in one of first and second logic states different from one another. A code monitoring device operates for detecting at least a preset number of successive chips in the first logic state in the pseudo random noise, and for changing at least one among the detected preset number of successive chips to the second logic state to convert the pseudo random noise code into a transmission signal. A driving device operates for activating and deactivating an electromagnetic wave generating device in response to the transmission signal. A receiving device operates for receiving an echo wave caused by reflection of an electromagnetic wave generated by the electromagnetic wave generating device at an object. A distance to the object is detected on the basis of the received echo wave.
    Type: Application
    Filed: May 3, 2002
    Publication date: November 14, 2002
    Inventors: Noriaki Shirai, Katsuhiro Morikawa
  • Patent number: 6466863
    Abstract: An object in front of a vehicle is detected. At least one of a steering angle of the vehicle and a yaw rate thereof is detected. First curvature data are generated on the basis of at least one of the detected steering angle and the detected yaw rate. The first curvature data represent a course along which the vehicle will travel. A determination is made as to whether or not the detected object is a stationary object. In cases where the detected object is a stationary object, second curvature data are generated on the basis of the stationary object. The second curvature data represent a course along which the vehicle will travel. The first curvature data and the second curvature data are averaged. Third curvature data are generated in response to a result of the averaging. The third curvature data represent a course along which the vehicle will travel.
    Type: Grant
    Filed: April 20, 2001
    Date of Patent: October 15, 2002
    Assignee: Denso Corporation
    Inventors: Noriaki Shirai, Katsuhiro Morikawa
  • Publication number: 20020131035
    Abstract: In a shift clock signal generating apparatus, a delay line includes a plurality of unit delay elements connected in cascade. A reference clock signal propagates in the delay line while being successively delayed by the unit delay elements. Switches have first ends connected with output terminals of the unit delay elements respectively, and second ends connected with a shift clock signal output path. When specified one among the switches is in its on position, a delayed clock signal which results from delaying the reference clock signal by a prescribed time interval is transmitted via the specified switch to the shift clock signal output path as a shift clock signal. The specified one among the switches is determined on the basis of data representing a phase difference of the shift clock signal from the reference clock signal. The specified switch is set in its on position.
    Type: Application
    Filed: March 5, 2002
    Publication date: September 19, 2002
    Inventors: Takamoto Watanabe, Hirohumi Isomura, Katsuhiro Morikawa
  • Patent number: 6380885
    Abstract: Height-wise positions of objects are detected on the basis of distances to the objects from a vehicle, angles of the objects in a width-wise direction of the vehicle, and angles of the objects in a height-wise direction of the vehicle. A plurality of objects, which satisfy conditions predetermined depending on physical characteristics of delineators, are determined to be objects composing a delineator group. When the detected height-wise position of an object in the delineator group which is nearest to the vehicle corresponds to a predetermined value or less, the delineator group is determined to be a delineator group on a road surface. A determination is made as to whether each object in the on-road-surface delineator group is a non-delineator in response to conditions of the detected height-wise positions of the objects in the on-road-surface delineator group.
    Type: Grant
    Filed: March 13, 2001
    Date of Patent: April 30, 2002
    Assignee: Denso Corporation
    Inventors: Noriaki Shirai, Katsuhiro Morikawa
  • Publication number: 20020044080
    Abstract: A radar device operates for emitting a detection wave ahead of a vehicle, and detecting objects in response to echoes of the emitted detection wave. A reflector detecting device operates for detecting reflectors among the objects detected by the radar device. The detected reflectors are located along a road. A reflector-row extracting device operates for, in cases where there are a plurality of rows of the reflectors detected by the reflector detecting device in one side of the vehicle, extracting one from among the reflector rows. A road-shape recognizing device operates for recognizing a shape of the road on the basis of the reflector row extracted by the reflector-row extracting device.
    Type: Application
    Filed: April 25, 2001
    Publication date: April 18, 2002
    Inventors: Noriaki Shirai, Katsuhiro Morikawa
  • Publication number: 20010053955
    Abstract: An object in front of a vehicle is detected. At least one of a steering angle of the vehicle and a yaw rate thereof is detected. First curvature data are generated on the basis of at least one of the detected steering angle and the detected yaw rate. The first curvature data represent a course along which the vehicle will travel. A determination is made as to whether or not the detected object is a stationary object. In cases where the detected object is a stationary object, second curvature data are generated on the basis of the stationary object. The second curvature data represent a course along which the vehicle will travel. The first curvature data and the second curvature data are averaged. Third curvature data are generated in response to a result of the averaging. The third curvature data represent a course along which the vehicle will travel.
    Type: Application
    Filed: April 20, 2001
    Publication date: December 20, 2001
    Inventors: Noriaki Shirai, Katsuhiro Morikawa
  • Publication number: 20010037165
    Abstract: The radius of the curvature of the lane on which a subject vehicle is traveling, is calculated in accordance with the turning condition of the subject vehicle and the velocity of the subject vehicle is obtained on the basis of the steering angle, and the yaw rate. An instantaneous probability of the same lane that the recognized object target exists on the same lane is calculated. In this operation, the instantaneous probability is compensated. That is, the road shape is recognized with delineator or the like. The instantaneous probability of the same lane is compensated on the basis of the recognized road shape. The probability of the same lane is calculated after a predetermined filtering process with the compensated instantaneous probability of the same lane. The preceding vehicle is selected on the basis of the probability of the same lane.
    Type: Application
    Filed: March 26, 2001
    Publication date: November 1, 2001
    Inventors: Noriaki Shirai, Katsuhiro Morikawa
  • Publication number: 20010026238
    Abstract: Height-wise positions of objects are detected on the basis of distances to the objects from a vehicle, angles of the objects in a width-wise direction of the vehicle, and angles of the objects in a height-wise direction of the vehicle. A plurality of objects, which satisfy conditions predetermined depending on physical characteristics of delineators, are determined to be objects composing a delineator group. When the detected height-wise position of an object in the delineator group which is nearest to the vehicle corresponds to a predetermined value or less, the delineator group is determined to be a delineator group on a road surface. A determination is made as to whether each object in the on-road-surface delineator group is a non-delineator in response to conditions of the detected height-wise positions of the objects in the on-road-surface delineator group.
    Type: Application
    Filed: March 13, 2001
    Publication date: October 4, 2001
    Inventors: Noriaki Shirai, Katsuhiro Morikawa
  • Publication number: 20010025211
    Abstract: A transmission wave is applied to a predetermined angular range in a width-wise direction of a vehicle. Object-unit data pieces containing at least data pieces representing distances to objects in correspondence with vehicle-width-wise direction angles are generated on the basis of a reflected wave. A determination is made as to whether each object is moving or stationary on the basis of a speed of the vehicle and a relative speed of the object. From the object-unit data pieces, ones are extracted which are effective for road shape recognition on the basis of a result of determining whether each object is moving or stationary. Ones of the extracted object-unit data pieces which represent monotonically increasing distances as viewed along one of clockwise and counterclockwise angle directions are grouped to generate data representing a road-side-object group. A road edge is recognized on the basis of the data representing the road-side-object group.
    Type: Application
    Filed: February 27, 2001
    Publication date: September 27, 2001
    Inventors: Noriaki Shirai, Katsuhiro Morikawa
  • Publication number: 20010020201
    Abstract: A transmission wave is applied to a predetermined angular range in a width-wise direction of a vehicle. A position of each object and a relative speed of the object are detected on the basis of the reflected wave. A determination is made as to whether each object is moving or stationary on the basis of the detected relative speed of the object and a speed of the vehicle. For at least one of right-hand and left-hand sides of the vehicle, calculation is given of a vehicle width-wise direction position where each stationary object effective for road shape recognition passes through the related side of the vehicle. The calculated vehicle width-wise direction position is memorized. A line connecting the memorized vehicle width-wise direction position and the detected position of the currently handled object corresponding to the effective stationary object is recognized as a road edge.
    Type: Application
    Filed: February 23, 2001
    Publication date: September 6, 2001
    Inventors: Noriaki Shirai, Katsuhiro Morikawa
  • Patent number: 6147637
    Abstract: An automotive obstacle detecting system is provided which includes a radar to measure the distance to a target present within a detectable zone. The system monitors a distance limit measurable by the radar and determines a reduction in ability to measure the distance to the target by comparing the distance limit with a given reference value.
    Type: Grant
    Filed: July 23, 1998
    Date of Patent: November 14, 2000
    Assignee: DENSO Corporation
    Inventors: Katsuhiro Morikawa, Tetsuya Nakamura