Patents by Inventor Alex Chiang

Alex Chiang 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: 8804475
    Abstract: Aspects of the disclosure provide a method for calibrating gains of an optical storage servo system having a plant. The method includes translating a first signal of the plant from a time domain effort signal into a frequency domain effort signal, translating a second signal of the plant from a time domain error signal into a frequency domain error signal, determining a first gain of the optical storage servo system based on the first signal and the second signal, comparing a third signal from an optical disk of the optical storage servo system with a predetermined threshold, and asserting a defect flag when the third signal drops below the predetermined threshold to avoid calibrating the first gain based on the first signal and the second signal.
    Type: Grant
    Filed: September 9, 2013
    Date of Patent: August 12, 2014
    Assignee: Marvell International Ltd.
    Inventors: Yuan Zheng, Alex Chiang, Enya Cheng
  • Patent number: 8531935
    Abstract: Aspects of the disclosure provide a method for calibrating gains of an optical storage servo system having a plant. The method includes translating a first signal of the plant from a time domain effort signal into a frequency domain effort signal, translating a second signal of the plant from a time domain error signal into a frequency domain error signal, determining a first gain of the optical storage servo system based on the first signal and the second signal, comparing a third signal from an optical disk of the optical storage servo system with a predetermined threshold, and asserting a defect flag when the third signal drops below the predetermined threshold to avoid calibrating the first gain based on the first signal and the second signal.
    Type: Grant
    Filed: August 22, 2012
    Date of Patent: September 10, 2013
    Assignee: Marvell International Ltd.
    Inventors: Yuan Zheng, Alex Chiang, Enya Cheng
  • Patent number: 8259542
    Abstract: A gain calibration method for optical storage servo systems in which, plant gain calibration is used by injecting a reference sine wave r into an optical storage servo system, obtaining an effort signal m at the input of the servo plant and an error signal y at the output of the servo plant, using a DFT (Discrete Fourier Transformation) to translate the time domain signals m and y into frequency responses M and Y, calculating a Y-to-M ratio, and using the magnitude of the Y-to-M ratio as the plant gain K of the servo system. The servo system's sensor gain K1 at the outermost layer of a disk may be calibrated by, e.g., the conventional peak-to-peak measurement. Since K=K1·K2, the servo system's actuator gain K2 at the outermost layer of the disk may be obtained. Because the actuator gain K2 is the same for all layers of a disk, the variation of the sensor gain K1 at an inner layer may follow that of the plant gain K at that layer.
    Type: Grant
    Filed: June 28, 2011
    Date of Patent: September 4, 2012
    Assignee: Marvell International Ltd.
    Inventors: Yuan Zheng, Alex Chiang, Enya Cheng
  • Patent number: 7974160
    Abstract: A gain calibration method for optical storage servo systems in which, plant gain calibration is used by injecting a reference sine wave r into an optical storage servo system, obtaining an effort signal m at the input of the servo plant and an error signal y at the output of the servo plant, using a DFT (Discrete Fourier Transformation) to translate the time domain signals m and y into frequency responses M and Y, calculating a Y-to-M ratio, and using the magnitude of the Y-to-M ratio as the plant gain K of the servo system. The servo system's sensor gain K1 at the outermost layer of a disk may be calibrated by, e.g., the conventional peak-to-peak measurement. Since K=K1·K2, the servo system's actuator gain K2 at the outermost layer of the disk may be obtained. Because the actuator gain K2 is the same for all layers of a disk, the variation of the sensor gain K1 at an inner layer may follow that of the plant gain K at that layer.
    Type: Grant
    Filed: August 15, 2008
    Date of Patent: July 5, 2011
    Assignee: Marvell International Ltd.
    Inventors: Yuan Zheng, Alex Chiang, Enya Cheng
  • Patent number: 6328718
    Abstract: A snivel sucker has a hollow main body, a lower cover disposed on a bottom of the hollow main body, a battery disposed in the hollow main body, a male top casing disposed on a top portion of the hollow main body, a female top casing disposed on the top portion of the hollow main body, the male top casing engaging with the female top casing, and a collector device disposed on a front portion of the male top casing. A motor receiving seat, a rubber cushion, a positioning seat, a rubber plate, and a connection mount are disposed between the male top casing and the female top casing. A motor is disposed in the motor receiving seat.
    Type: Grant
    Filed: April 29, 2000
    Date of Patent: December 11, 2001
    Inventors: Alex Chiang, Chein-Li Chen