Patents by Inventor Xiaodong Che

Xiaodong Che 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: 11688427
    Abstract: Example read transducers, data storage devices, and methods to provide an angled free layer for generating and decoding multi-level read signals are described. The read transducer includes a free layer having a magnetization bias sensitive to an external magnetic field and the direction of the magnetization bias forms an acute angle relative to a surface of the non-volatile storage medium generating the external magnetic field. The read transducer also includes a pinned layer having a fixed magnetization and a direction of the fixed magnetization forms a right angle with the magnetization bias of the free layer. The read transducer targets a readback location on a track boundary between adjacent tracks and generates a read signal indicative of perpendicular and cross-track fields of the adjacent tracks.
    Type: Grant
    Filed: February 24, 2022
    Date of Patent: June 27, 2023
    Assignee: Western Digital Technologies, Inc.
    Inventors: Zhen Jin, Xiaodong Che
  • Publication number: 20190037388
    Abstract: The present invention provides a user device, communication method, and computer storage medium.
    Type: Application
    Filed: July 18, 2016
    Publication date: January 31, 2019
    Inventor: Xiaodong CHE
  • Publication number: 20190028929
    Abstract: The present invention provides a data-interface flow-splitting method, apparatus, and terminal device. The data transmission method includes: detecting, by a first terminal, connectivity of each data interface in real time; after the first terminal detects that data needs to be transmitted, according to an initial splitting weight, allocating a plurality of established links to data interfaces in an ‘UP’ state for data transmission; and during transmission of the data, calculating a real-time splitting weight, and according to the real-time splitting weight, allocating newly established links to data interfaces in the ‘UP’ state for data transmission. The present invention also provides a computer storage medium.
    Type: Application
    Filed: July 18, 2016
    Publication date: January 24, 2019
    Applicant: NUBIA TECHNOLOGY CO., LTD.
    Inventor: Xiaodong CHE
  • Patent number: 8736996
    Abstract: A method, apparatus, and system for implementing channel signal processing assist with an embedded contact sensor (ECS) in hard disk drives. An ECS signal is captured during write and idle operation of the hard disk drive. A read channel monitors changes in the ECS signal providing a clearance monitor function for insuring write integrity.
    Type: Grant
    Filed: May 18, 2012
    Date of Patent: May 27, 2014
    Assignee: HGST Netherlands B.V.
    Inventors: Xiaodong Che, Weldon Mark Hanson
  • Publication number: 20130308220
    Abstract: A method, apparatus, and system for implementing channel signal processing assist with an embedded contact sensor (ECS) in hard disk drives. An ECS signal is captured during write and idle operation of the hard disk drive. A read channel monitors changes in the ECS signal providing a clearance monitor function for insuring write integrity.
    Type: Application
    Filed: May 18, 2012
    Publication date: November 21, 2013
    Applicant: HGST NETHERLANDS B.V.
    Inventors: Xiaodong Che, Weldon Mark Hanson
  • Patent number: 8537496
    Abstract: A perpendicular magnetic write head having improved Bit Error Rate (BER), Adjacent Track Interference (ATI) and Far Track Interference (FTI). The write head includes a write pole and a trailing wrap-around magnetic shield. A permanent magnetic is located at either outer side of the shield. These magnets are magnetized to have magnetizations that are oriented in the same direction, in a direction that is perpendicular to the track direction and parallel with the air bearing surface.
    Type: Grant
    Filed: July 27, 2010
    Date of Patent: September 17, 2013
    Assignee: HGST Netherlands B.V.
    Inventors: Zhihao Li, Xiaodong Che, Zhen Jin, Yansheng Luo
  • Patent number: 8405927
    Abstract: A low flying slider detector is disclosed. In one embodiment a surface is provided. In addition, a suspender is provided for receiving and flying a slider above the surface. A detector is also provided for detecting a low flying slider flying above the surface wherein the detector does not require measuring of the slider fly height to detect the low flying slider and wherein the detecting of the low flying slider is performed at least at a slider level of assembly.
    Type: Grant
    Filed: October 2, 2006
    Date of Patent: March 26, 2013
    Assignee: HGST Netherlands B.V.
    Inventors: Xiaodong Che, Xiao Z. Wu
  • Patent number: 8120866
    Abstract: A method for characterizing a magnetic-recording system for the presence of adjacent-track interference and far-track interference. The method includes writing a plurality of repeating pulse-waveforms on a data track of a magnetic-recording disk at a write element of a magnetic-recording head. The method further includes reading a plurality of read-back signals from the magnetic-recording disk over a band of pseudo-data tracks offset from the data track by corresponding pseudo-data-track offsets in a radial direction of the magnetic-recording disk at a read element of the magnetic-recording head. In addition, the method includes displaying a magnetic-recording-signature map synthesized from the read-back signals from the magnetic-recording disk.
    Type: Grant
    Filed: July 29, 2009
    Date of Patent: February 21, 2012
    Assignee: Hitachi Global Storage Technologies, Netherlands B.V.
    Inventors: Xiaodong Che, Zhen Jin, Michael Salo, Roger Wood
  • Patent number: 8116021
    Abstract: A hard disk drive (HDD) including a magnetic disk, the magnetic disk including a data track. The HDD also includes a synchronized rewrite controller for synchronizing a plurality of rewrites of a data pattern on a location of the track of the magnetic disk and the HDD includes a write head controlled by the synchronized rewrite controller for writing the data pattern on the location of the data track and rewriting the data pattern a plurality of times on the location in synchronization with a prior writing of the data pattern on the data track.
    Type: Grant
    Filed: December 2, 2009
    Date of Patent: February 14, 2012
    Assignee: Hitachi Global Storage Technologies Netherlands B.V.
    Inventors: Michael Alex, Xiaodong Che, Zhen Jin, Michael Paul Salo
  • Publication number: 20120026628
    Abstract: A perpendicular magnetic write head having improved Bit Error Rate (BER), Adjacent Track Interference (ATI) and Far Track Interference (FTI). The write head includes a write pole and a trailing wrap-around magnetic shield. A permanent magnetic is located at either outer side of the shield. These magnets are magnetized to have magnetizations that are oriented in the same direction, in a direction that is perpendicular to the track direction and parallel with the air bearing surface.
    Type: Application
    Filed: July 27, 2010
    Publication date: February 2, 2012
    Inventors: Zhihao Li, Xiaodong Che, Zhen Jin, Yansheng Luo
  • Patent number: 7986492
    Abstract: A patterned disk for a hard disk drive. The patterned disk includes a magnetic material over a substrate. The magnetic material includes a plurality of grooves. The grooves are filled with a lubricant that is hardened with UV exposure or some other hardening process. The lubricant provides a protective cover for the magnetic material exposed by the grooves. The use of lubricants in the fabrication of disks is known, thus the process does not introduce a process step that requires special equipment and/or process development.
    Type: Grant
    Filed: September 6, 2007
    Date of Patent: July 26, 2011
    Assignee: Samsung Electronics Co., Ltd.
    Inventors: Kiseok Moon, Hyungjai Lee, Carl Xiaodong Che
  • Publication number: 20110128646
    Abstract: A hard disk drive (HDD) including a magnetic disk, the magnetic disk including a data track. The HDD also includes a synchronized rewrite controller for synchronizing a plurality of rewrites of a data pattern on a location of the track of the magnetic disk and the HDD includes a write head controlled by the synchronized rewrite controller for writing the data pattern on the location of the data track and rewriting the data pattern a plurality of times on the location in synchronization with a prior writing of the data pattern on the data track.
    Type: Application
    Filed: December 2, 2009
    Publication date: June 2, 2011
    Inventors: Michael Alex, Xiaodong Che, Zhen Jin, Michael Paul Salo
  • Patent number: 7885028
    Abstract: A hard disk drive with a disk that has a plurality of data bits. The drive includes a circuit that reads each data bit n times and selects a value for the bit based on the most frequent occurrence of one of a plurality of values. This process provides a voting technique that enhances the quality of accurately captured data.
    Type: Grant
    Filed: April 8, 2008
    Date of Patent: February 8, 2011
    Assignee: Samsung Electronics Co., Ltd.
    Inventors: Yawshing Tang, Carl Xiaodong Che, Na-Young Kim
  • Publication number: 20110026154
    Abstract: A method for characterizing a magnetic-recording system for the presence of adjacent-track interference and far-track interference. The method includes writing a plurality of repeating pulse-waveforms on a data track of a magnetic-recording disk at a write element of a magnetic-recording head. The method further includes reading a plurality of read-back signals from the magnetic-recording disk over a band of pseudo-data tracks offset from the data track by corresponding pseudo-data-track offsets in a radial direction of the magnetic-recording disk at a read element of the magnetic-recording head. In addition, the method includes displaying a magnetic-recording-signature map synthesized from the read-back signals from the magnetic-recording disk.
    Type: Application
    Filed: July 29, 2009
    Publication date: February 3, 2011
    Inventors: Xiaodong Che, Zhen Jin, Michael Salo, Roger Wood
  • Patent number: 7876519
    Abstract: A method for erasing a disk of a hard disk drive. The method includes moving the hard disk drive adjacent to an erasure head that emanates a magnetic field. The magnetic field and moving hard disk drive cause a disk of the hard disk drive to spin under a Lorentz force created by the magnetic field and moving disk. The magnetic field is applied by the erasure head for a duration that causes erasure of the entire disk. The spindle motor is not activated during the entire process. Not activating the spindle motor eliminates any Faraday coupling from the erasure head into the motor.
    Type: Grant
    Filed: December 16, 2008
    Date of Patent: January 25, 2011
    Assignee: Samsung Electronics Co., Ltd.
    Inventors: Carl Xiaodong Che, Keung Youn Cho, Soo-Youl Hong, Shuo-Hao Chen
  • Patent number: 7830632
    Abstract: A hard disk drive with a disk that includes a first group of tracks and a second group of tracks. The second group of tracks are used to write large blocks of data. For example, data in the second group may be video or audio. The second group of tracks has a higher track density than the first group of tracks. The large data block is written sequentially in the second group of tracks so that there is only one adjacent track write within the group. Using only one adjacent track write allows the tracks within the second group to be overlapped to increase track density.
    Type: Grant
    Filed: June 19, 2007
    Date of Patent: November 9, 2010
    Assignee: Samsung Electronics Co., Ltd.
    Inventors: Yawshing Tang, Carl Xiaodong Che
  • Patent number: 7821736
    Abstract: Write elements are discussed having a write pole and an associated trailing shield. A leading side of the trailing shield faces a trailing side of the write pole. The leading side of the trailing shield has a shape such that a center portion of the leading side has less of a separation from the trailing side of the write pole than track edge portions of the leading side of the trailing shield. An exemplary shape the leading side of the trailing shield may be a convex shape when viewed from the ABS. The shape of the leading side of the trailing shield causes the trailing shield to shunt less of the magnetic field from the trailing side of the write pole at the track edges so that the written transition at the track edge will not lag behind the written transition at the track center allowing for a straighter transition.
    Type: Grant
    Filed: April 6, 2006
    Date of Patent: October 26, 2010
    Assignee: Hitachi Global Storage Technologies Netherlands, B.V.
    Inventors: Xiaodong Che, Wen-Chien Hsiao, Yimin Hsu, Vladimir Nikitin
  • Patent number: 7773336
    Abstract: A hard disk drive that determines a flying height from a ratio of a first harmonic transfer function and a third harmonic transfer function. The transfer functions can be determined from a response to an impulse function. The impulse function (also known as an impulse response) can be a playback waveform de-convolved by channel data sequence. Any change in the ratio of the first and third harmonic transfer functions corresponds to a change in the flying height. The disk drive may utilize the transfer function ratios in a feedback routine to control the flying height.
    Type: Grant
    Filed: November 25, 2008
    Date of Patent: August 10, 2010
    Assignee: Samsung Electronics Company, Ltd.
    Inventors: Carl Xiaodong Che, Yawshing Tang, Haejung Lee
  • Patent number: 7768728
    Abstract: A disk drive that includes a head and a disk. The disk drive also includes a circuit that can detect head/disk contact from a jitter determined from a read signal provided by the head. The jitter may correspond to the time interval between two detected sync marks. Alternatively, the jitter may correspond to a change in frequency of a read clock generated from the read signal. These approaches allow for detection of head movement in a down track direction. Down track is a direction that is essentially parallel with the longitudinal axis of the head.
    Type: Grant
    Filed: December 10, 2007
    Date of Patent: August 3, 2010
    Assignee: Samsung Electronics Co., Ltd.
    Inventors: Yawshing Tang, Carl Xiaodong Che
  • Publication number: 20100177418
    Abstract: A hard disk drive with a patterned disk that has a discrete track. The disk drive includes a controller that controls a head and a voice coil motor to optimize a writing of information onto the discrete track. Writing optimization can occur by initially writing a track of information and recording the write position. The written track is then located by reading the information with a read element of a drive head and analyzing a quality of the read signal, such as signal amplitude or error rate. The read position is then recorded. The information is erased and the head is moved. The process of writing, finding the written track location, storing the write and read positions and again moving the head is repeated. The write and read positions that provide the best quality signal is saved and subsequently used to write and read data on the discrete track.
    Type: Application
    Filed: January 14, 2009
    Publication date: July 15, 2010
    Applicant: Samsung Electronics Co., Ltd.
    Inventors: Yawshing Tang, Carl Xiaodong Che