Abstract: A hard disk drive device and a method and apparatus for control of the hard disk drive is provided. The hard disk drive includes disk media, a slider head, a head gimbal assembly and a control means. The disk media includes at least two layers for data storage. The slider head flies above the disk media and includes a writer and a reader, and a head gimbal assembly supports the slider head above the disk media. The control means is physically coupled to the head gimbal assembly and electrically coupled to the writer and the reader for reducing write interference from the writer when the writer is writing to the disk media while the reader is reading from the disk media, wherein write interference is reduced in one or more of a time domain and a frequency domain.

Abstract: A system including a write head, a read head, a mixer, and a filter. The write head is configured to write a pattern on a track of a medium of a hard disk drive, wherein the pattern has a first frequency. The read head is configured to read the pattern written on the track of the medium of the hard disk drive. The mixer is configured to mix a first signal generated by reading the pattern with a second signal to obtain a mixed signal. The second signal has a second frequency, and wherein the second frequency is different than the first frequency. The filter is configured to filter the mixed signal to determine a relative head-to-disk speed. The filter has a parameter selected based on a difference between the first frequency and the second frequency.

Abstract: Various embodiments provide a recording medium. The recording medium may include: a dedicated servo layer for providing servo information, wherein the dedicated servo layer comprises a plurality of tracks, wherein a first track comprises a first servo signal of a first frequency, wherein a second track comprises a second servo signal of a second frequency, and wherein the first servo signal and the second servo signal comprise a common single tone signal.

Abstract: Various embodiments provide a recording medium. The recording medium may include a dedicated servo layer for providing servo information. The dedicated servo layer may include a plurality of tracks. A first track may include a first servo signal. A second track may include a second servo signal. The first servo signal and the second servo signal may include a plurality of common transitions. The transitions may be provided at a pre-determined frequency.

Abstract: In the present disclosure, a recording medium and a method of preparing a recording medium is provided. In a recording medium, a first annular servo track can be provided on a first layer of the recording medium, and second annular servo track can be provided on the first layer of the recording medium. The second annular servo track can be adjacent to the first annular servo track. In the recording medium, the first annular servo track and the second annular servo track are magnetically polarized and are magnetically opposing in polarity. A corresponding method of preparing a recording medium is provided.

Abstract: A storage medium including a servo layer, a data recording layer, a heat sink layer, and a diamond-like carbon layer with a lubricant covering. The servo layer is configured to store servo information on the storage medium. The servo information is used to position a read/write head over the storage medium during a read/write operation performed by the read/write head on the storage medium. The data recording layer is configured to store data on the storage medium during the read/write operation performed by the read/write head on the storage medium. The heat sink layer is disposed between the servo layer and the data recording layer. The diamond-like carbon layer with the lubricant covering is disposed above the data recording layer.

Abstract: A servo system for writing servo information on a recording medium of a hard disk drive and for determining head position based on the servo information with a tracking accuracy, the servo system including a first magnetic head and a servo writer. The servo writer is configured to write the servo information on the recording medium by forming, using the first magnetic head, a first servo pattern comprising a servo burst pattern on a segment of a first track of a first layer of the recording medium; and by forming a second servo pattern comprising addressing information on a segment of a second track of a second layer of the recording medium. The second track is arranged half a width of the first track from the first track to increase the tracking accuracy of the servo system.

Abstract: According to various embodiments, a method for reading data from a storage medium using a reader, wherein the reader includes at least one reader head, may be provided, wherein the storage medium includes a plurality of tracks. The method may include: reading a first signal with a reader head of the reader at a pre-determined position of the storage medium; reading a second signal with a reader head of the reader at the pre-determined position of the storage medium; and determining data stored at the pre-determined position of the storage medium based on the first signal and based on the second signal.

Abstract: A system for tracking a position error of a read/write head. The read/write head is configured to read data recorded to a data layer of a recording medium and read servo information recorded to a dedicated servo layer of the recording medium. To read the servo information, the read/write head is configured to read, from a first track, a first servo signal including first servo bursts of a predetermined frequency, and read, from a second track adjacent to the first track, a second servo signal including second servo bursts of the predetermined frequency. The first servo bursts are orthogonal to the second servo bursts. A position error signal determination circuit is configured to determine the position error using at least one of the first servo signal and the second servo signal.

Abstract: A system for reading data from a storage medium. The system includes a reader and a data determination circuit. The reader is configured to receive a first signal from a first position relative to the storage medium and read a second signal from a second position relative to the storage medium. Each of the first signal and the second signal includes a combination of first data stored in a first track and second data stored in a second track. The data determination circuit is configured to determine third data stored at a predetermined position using the combination of the first data stored in the first track and the second data stored in the second track as received in the first signal and the combination of the first data stored in the first track and the second data stored in the second track as received in the second signal.

Abstract: A servo system for writing servo information on a recording medium of a hard disk drive and for determining head position based on the servo information with a tracking accuracy, the servo system including a first magnetic head and a servo writer. The servo writer is configured to write the servo information on the recording medium by forming, using the first magnetic head, a first servo pattern comprising a servo burst pattern on a segment of a first track of a first layer of the recording medium; and by forming a second servo pattern comprising addressing information on a segment of a second track of a second layer of the recording medium. The second track is arranged half a width of the first track from the first track to increase the tracking accuracy of the servo system.

Abstract: According to an embodiment of the present invention, a data storage device comprising a motor having a stator is disclosed. The stator may include a substrate having a first surface and a second surface opposite to the first surface; and a n-phase winding arrangement having n phase windings; wherein each phase winding comprises m flat fractional-pitch coils arranged on the first surface of the substrate such that the coils are spaced apart uniformly along a closed loop and connected in series; wherein each coil together with an angular section of the substrate between the coil and an adjacent coil of the same phase winding defines a stator pole-pair; and wherein m is an integer larger than 1.

Abstract: A system for reading data from a storage medium. The system includes a reader and a data determination circuit. The reader is configured to receive a first signal from a first position relative to the storage medium and read a second signal from a second position relative to the storage medium. Each of the first signal and the second signal includes a combination of first data stored in a first track and second data stored in a second track. The data determination circuit is configured to determine third data stored at a predetermined position using the combination of the first data stored in the first track and the second data stored in the second track as received in the first signal and the combination of the first data stored in the first track and the second data stored in the second track as received in the second signal.

Abstract: A device may be provided. The device includes a media including a servo layer and a data recording layer, and a recording head including a dimension sized to produce a magnetic writing field to write servo information on the servo layer.

Abstract: A method of encoding an input data into a codeword that satisfy a k constraint includes partitioning the input data into a plurality of data blocks comprising a first data block and a plurality of remaining data blocks; performing a first analysis of the plurality of data blocks for modifying each of the plurality of remaining data blocks that satisfy a first predetermined criterion; performing a second analysis of the plurality of data blocks after the first analysis for modifying each of the plurality of data blocks that satisfy a second predetermined criterion; and converting each bit of the plurality of data blocks after the second analysis to produce the codeword in Non-Return-to-Zero (NRZ) format with the k constraint. There is also provided a method of decoding the codeword with satisfies the k constraint into an output data, and the corresponding encoder and decoder.

Abstract: A system including a write head, a read head, a mixer, and a filter. The write head is configured to write a pattern on a track of a medium of a hard disk drive, wherein the pattern has a first frequency. The read head is configured to read the pattern written on the track of the medium of the hard disk drive. The mixer is configured to mix a first signal generated by reading the pattern with a second signal to obtain a mixed signal. The second signal has a second frequency, and wherein the second frequency is different than the first frequency. The filter is configured to filter the mixed signal to determine a relative head-to-disk speed. The filter has a parameter selected based on a difference between the first frequency and the second frequency.

Abstract: A system for tracking a position error of a read/write head. The read/write head is configured to read data recorded to a data layer of a recording medium and read servo information recorded to a dedicated servo layer of the recording medium. To read the servo information, the read/write head is configured to read, from a first track, a first servo signal including first servo bursts of a predetermined frequency, and read, from a second track adjacent to the first track, a second servo signal including second servo bursts of the predetermined frequency. The first servo bursts are orthogonal to the second servo bursts. A position error signal determination circuit is configured to determine the position error using at least one of the first servo signal and the second servo signal.

Abstract: According to embodiments of the present invention, a method for providing a synchronization signal for at least one of a read operation or a write operation carried out by means of a head in a data storage device is provided. The method includes obtaining a readback servo signal from a storage medium of the data storage device by means of the head, the readback servo signal having at least one frequency associated with a servo track of the storage medium, frequency mixing the readback servo signal with a local signal having a local frequency to provide a frequency mixed signal, and filtering the frequency mixed signal to provide the synchronization signal for at least one of the read operation or the write operation. According to further embodiments of the present invention, a data storage device is also provided.

Abstract: A method for measuring a change in a spacing between a head and a storage medium of a data storage system. The method includes obtaining a first readback signal from the storage medium using the head at a first spacing between the head and the storage medium, determining a first power spectrum density over a frequency range from the obtained first readback signal, obtaining a second readback signal from the storage medium using the head at a second spacing between the head and the storage medium, determining a second power spectrum density over the frequency range from the obtained second readback signal, and providing a measurement indicative of the change in the spacing based on the determined first power spectrum density and the determined second power spectrum density. A data storage system is also provided.

Abstract: In various embodiments, a method of writing servo information to a recording medium may be provided. The method include forming a first servo pattern (including a servo burst pattern) on a segment of a first track of a first layer of the recording medium, the first track having a track width. The method may further include forming a second servo pattern (including addressing information) on a segment of a second track of a second layer of the recording medium. The second track is arranged from the first track by half the track width.