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
  • 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
  • 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: 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: 7542227
    Abstract: A hard disk drive that determines a flying height from a slope of a line created from a ratio of amplitudes of frequencies in response to impulse functions. A first set of amplitudes of reference frequencies can be determined from a reference impulse. A second set of amplitudes of data frequencies can be determined from a data impulse during operation of the disk drive. Ratios of amplitudes of the data and reference frequencies at different discrete frequencies can be plotted. The slope of the plotted line corresponds to the difference between the flying height when the reference impulse is generated and the flying height when the data impulse is generated. The disk drive may utilize the slope in a feedback routine to control the flying height.
    Type: Grant
    Filed: June 29, 2007
    Date of Patent: June 2, 2009
    Assignee: Samsung Electronics Co., Ltd.
    Inventors: Xiaodong Che, Yawshing Tang
  • Patent number: 7538963
    Abstract: A disk drive that protects stored data from stray magnetic fields is disclosed. Sensors for sensing stray magnetic fields are mounted to the base and/or cover of the drive and aligned with the trajectory of the movement of the read/write head. If the sensors, which have memory such as a toggle switch, are exposed to a high stray magnetic field, operation of the drive is suspended until a follow-up algorithm or protocol is implemented. The sensors can sense specific direction of stray fields. The sensor can change resistance if a high stray field is detected. The information in the sensors is collected and processed by the drive controller.
    Type: Grant
    Filed: March 27, 2006
    Date of Patent: May 26, 2009
    Assignee: Hitachi Global Storage Technologies Netherlands B.V.
    Inventor: Xiaodong Che
  • Patent number: 7508628
    Abstract: A magnetic structure for use in a magnetic recording head, the structure having improved resistance to stray field writing. The magnetic structure can be for example a magnetic shield or a return pole of a perpendicular write element. The structure includes a main body portion which may have a generally rectangular configuration, and first and second wing portions extending laterally from the sides of the body at or near the ABS. The wing portions have a depth measured perpendicular to the ABS that is significantly less than the depth of the body portion (preferably less than 25 percent of the body portion). The wing portions may also have notches formed in their ABS edges. The wings conduct flux from the ABS edge of the body portion and create a flux choking effect for magnetic flux flowing into the wings.
    Type: Grant
    Filed: October 29, 2004
    Date of Patent: March 24, 2009
    Assignee: Hitachi Global Storage Technologies Netherlands B.V.
    Inventors: Xiaodong Che, Hardayal Singh Gill, Wen-chien Hsiao, Yangsheng Luo, Xiaoyu Sui
  • Publication number: 20090002870
    Abstract: A hard disk drive that determines a flying height from a slope of a line created from a ratio of amplitudes of frequencies in response to impulse functions. A first set of amplitudes of reference frequencies can be determined from a reference impulse. A second set of amplitudes of data frequencies can be determined from a data impulse during operation of the disk drive. Ratios of amplitudes of the data and reference frequencies at different discrete frequencies can be plotted. The slope of the plotted line corresponds to the difference between the flying height when the reference impulse is generated and the flying height when the data impulse is generated. The disk drive may utilize the slope in a feedback routine to control the flying height.
    Type: Application
    Filed: June 29, 2007
    Publication date: January 1, 2009
    Applicant: Samsung Electronics Co., Ltd.
    Inventors: Xiaodong Che, Yawshing Tang
  • Publication number: 20080259482
    Abstract: A magnetic media that has at least one groove. The groove is created by a process that includes initially forming a temporary layer over a magnetic layer of the disk. One or more grooves are formed in the temporary and magnetic layers. The temporary layer is removed and a protective layer is formed over the magnetic layer and within the groove.
    Type: Application
    Filed: April 20, 2007
    Publication date: October 23, 2008
    Applicant: Samsung Electronics Co., Ltd.
    Inventors: Kiseok Moon, Soo Youl Hong, Yawshing Tang, Xiaodong Che
  • Patent number: 7420759
    Abstract: Method calibrates an assembled hard disk drive for read head accessing rotating disk surface, by estimating non-linearity of that playback device based on two data patterns, which have a short transition-pair waveform and a long transition-pair waveform. By linearly constructing a simulated long transition-pair waveform from the short transition-pair waveform and aligning it with the long transition-pair waveform, non-linear distortion is estimated, creating the transfer curve as product of this process. The transfer curve is used to compensate the read data of a track to create the adjusted read data, which is used to decode the track being read. The adjusted read data is the product of this process. The hard disk drive including the transfer table. Second method using transfer table to create adjusted read data for track, the processor, embedded circuit and hard disk drive implementing this method. Manufacturing embedded circuit as product.
    Type: Grant
    Filed: October 31, 2006
    Date of Patent: September 2, 2008
    Assignee: Samsung Electronics Co., Ltd.
    Inventor: Xiaodong Che
  • Publication number: 20080158705
    Abstract: A write head tester is disclosed. The write head tester includes a rotatably coupled magnetic media having a stand-off thereover. In addition, a write head holder is fixedly coupled with the tester. The write head holder receives and electrically couples a removably coupleable write head such that the removably coupleable write head is capable of performing a write on the magnetic media. A read head is also fixedly coupled with the tester. The read head is utilized for performing a read on the magnetic media. Furthermore, an evaluator is provided for accessing a result of the read on the magnetic media and evaluating the removably coupleable write head based on the read.
    Type: Application
    Filed: December 28, 2006
    Publication date: July 3, 2008
    Inventors: Xiaodong Che, Wen-chien Hsiao, Yansheng Luo, Xiaoyu Sui