161results about "Digital recording" patented technology

A plurality of servo patterns are recorded in a magnetic tape along a longitudinal direction. The servo pattern is at least one linear magnetization region pair. The linear magnetization region pair includes a first linear magnetization region, which is linearly magnetized, and a second linear magnetization region, which is linearly magnetized. The first linear magnetization region and the second linear magnetization region are inclined in opposite directions with respect to a first imaginary straight line along a width direction of the magnetic tape. The first linear magnetization region has a steeper inclined angle with respect to the first imaginary straight line than the second linear magnetization region.

Described are systems, devices and methods for staggered bits magnetic recording. A staggered bits track pattern is recorded on granular magnetic recording media, thereby mapping a data bit sequence onto adjacent tracks so that the bits in one track are staggered relative to the bits in the adjacent track. A read head having an effective cross-track width extending across the tracks is aligned to read a sequence of combined bit signals as the read head is advanced in the down-track direction. Each combined bit signal combines one bit from each adjacent track. A data channel coupled to the read head is used to disambiguate the sequence of combined bit signals, thereby reproducing the data bit sequence.

To provide a magnetic recording device capable of stable recording operation.SOLUTION: A magnetic recording device 150 includes a magnetic recording medium group 20 and a magnetic head group 30. The magnetic recording medium group includes a first magnetic recording medium 21; a plurality of second magnetic recording media 22; and a plurality of third magnetic recording media 23. The magnetic head group includes a first magnetic head 31; a plurality of second magnetic heads 32; and a plurality of third magnetic heads 33. The first magnetic head can record data in the first magnetic recording medium by a first method. The plurality of second magnetic heads can record data in the plurality of second magnetic recording media by a second method. The plurality of third magnetic heads can record data in the plurality of third magnetic recording media by the second method. The first magnetic recording medium is provided between the plurality of second magnetic recording media and the plurality of third magnetic recording media in a first direction D1. The other magnetic recording medium in which the data is recorded by the first method does not overlap with the magnetic recording medium group in the first direction.SELECTED DRAWING: Figure 1

To provide a magnetic disk device capable of predicting whether error correction to a data track of a disk reaches a limit or not.SOLUTION: A magnetic disk device 1 includes a first disk having a first data track and a second data track, a first write head, a write processing unit, an error correction unit, a correction limit prediction unit 65, and a determination unit. During the write period, the correction limit prediction unit 65 calculates the excess amount OVR, calculates the metric value Mer by multiplying the excess amount OVR by the first weighting factor, updates the cumulative metric value ME, and generates the first prediction information. The determination unit determines whether to cause the write processing unit to continue the write processing on the second data track based on the first prediction information.SELECTED DRAWING: Figure 18

To provide an information processor, a magnetic recording reproduction device, and a magnetic recording reproduction system that can improve efficiency.SOLUTION: According to an embodiment, an information processor includes an acquisition part and a processing part. The processing part is configured to carry out first operation. The first operation includes first decoding, first accuracy evaluation, second decoding, and first determination operation. The first decoding includes processing a portion targeted for reproduction signal decoding by a first processing configuration to derive a first decoding result. When first accuracy of the first decoding result does not satisfy a first criterion, the second decoding includes processing the portion targeted for decoding by a second processing configuration to derive a second decoding result. The second processing configuration is at least partially different from the first processing configuration.SELECTED DRAWING: Figure 1

Described are systems, methods, and media for magnetic recording assisted by the use of ultrafast pulses such as ultrafast laser pulses. A layered magnetic medium includes a thin, magnetically softer capping layer disposed over a magnetically harder data recording layer. The capping layer is configured to have fast magnetization dynamics, and to have faster magnetization dynamics than the data recording layer. Due to the fast magnetization dynamics of the capping layer, ultrafast pulses can be used to assist a magnetic write field in magnetizing the capping layer without inducing any significant heating in the bulk of the media. The magnetization of the capping layer nucleates magnetization in the data recording layer under the influence of the magnetic write field.

To provide a magnetic recording device that can improve productivity and a manufacturing method thereof.SOLUTION: According to the embodiment, a magnetic recording device includes a magnetic recording medium, a magnetic head, and a control unit. The magnetic head includes a coil, a first magnetic pole, and a light-emission unit. The control unit performs a first operation and a second operation. In the first operation, the control unit records first servo position information to a first area of the magnetic recording medium. In the second operation, the control unit executes a repair operation when a first condition is not fulfilled. The first condition includes that the recording condition of the first servo position information is within a first range. In the repair operation, the control unit performs an erase operation for irradiating light from the light-emission unit to the first area, and performs a re-record operation for recording the first servo position information to the first area after the erase operation again.SELECTED DRAWING: Figure 1

Data is written in tracks in a first sub-region of a region of a disk using Shingled Magnetic Recording (SMR). It is determined whether a predetermined data storage capacity for the region can be reached by adding a sub-region guard band and shingle writing throughout a remaining portion of the region using a lower limit of track overlap. The sub-region guard band does not store data and separates the first sub-region from a second sub-region in the region. In response to determining that the predetermined data storage capacity for the region can be reached by adding the sub-region guard band and shingle writing with the lower limit of track overlap throughout the remaining portion of the region, the sub-region guard band is added, and the second sub-region is shingle written with at least as much track overlap as the lower limit of track overlap.

An indicator indicating a non-linearity of a servo pattern is within 15% or less of a track pitch. The track pitch is a pitch between tracks. The indicator indicates a degree of variation in the plurality of distance differences from an average value of the plurality of distance differences. The distance difference is a difference between a distance between a pair of first positions corresponding to each other in the width direction in the pair of servo patterns and a distance between a pair of second positions deviated from the pair of first positions in the width direction by a first predetermined interval in the pair of servo patterns. The plurality of distance differences are obtained by measuring the distance difference for each second predetermined interval along the width direction in the pair of servo patterns. The first predetermined interval is larger than the second predetermined interval.

The servo pattern recording method according to one aspect of the present technology involves recording a servo pattern in a plurality of servo bands that are arranged at intervals in the width direction of a magnetic layer in a magnetic tape, the method including: causing the magnetic tape to travel with a prescribed tension; and recording a servo pattern in the plurality of servo bands at a second pitch narrower than a first pitch, which is the positioning interval of two servo lead heads in a tape drive device that records data in the magnetic layer or that plays back data recorded in the magnetic layer.

According to one embodiment, multiple first positions are set in a radial direction of a magnetic disk. The multiple first positions include multiple second positions and a third position different from the multiple second positions. A controller of a magnetic disk apparatus executes a first process in which an RRO correction value is measured at each of the multiple second positions and measurement of an RRO correction value at the third position is skipped. After the first process, the controller executes a second process of performing write or read access to multiple tracks. The second process includes acquiring a position error signal by a read head during the write or read access, and calculating an RRO correction value for the third position based on the position error signal.

The present invention provides a magnetic disk device that can efficiently record parity and has excellent error correction capabilities for user data on the disk. [Solution] The magnetic disk device comprises a disk DK, a write head WHD, a volatile buffer memory 80, a parity generation unit, a write processing unit 62, an error correction unit 64, a storage processing unit 65, and a normal correction limit prediction unit 66. The parity generation unit generates a first normal parity and a first strong parity based on first user data, and generates a second normal parity and a second strong parity based on second user data. The storage processing unit 65 overwrites the first recording area of ​​the buffer memory with the second strong parity if the first prediction information is normal information, and if the first prediction information changes to abnormal information, it leaves the first strong parity in the first recording area and stores the second strong parity in the second recording area of ​​the buffer memory.

This invention provides a disk device capable of improving performance and data reliability, and a method for setting refresh thresholds. The disk device of this embodiment includes: a disk having a first track; a head having a heater for writing data to the disk and reading data from the disk; and a controller for setting variations in parameters associated with write processing to the disk within one cycle of the first track, such that variations in evaluation metrics corresponding to write / read processing characteristics are suppressed within one cycle of the first track.

A data storage device comprises a magnetic medium and a head configured to be actuated over the magnetic medium. The head comprises a write element and a write driver configured to generate a write current to be applied to the write element. The write driver comprises a data switch section configured to switchably output low-level signals and high-level signals, and a stationary cascode section configured to receive the low-level signals and high-level signals from the data switch section and to generate a cascode pass through current. The data switch section comprises low voltage CMOS devices and the stationary cascode section comprises high voltage CMOS devices.

The invention relates to the technical field of magnetic tape units, in particular to a magnetic tape driver, a magnetic tape unit and a storage system.The magnetic tape driver comprises a read head, an analog equalization circuit and a digital processing chip; the read head is coupled with the analog equalization circuit, the analog equalization circuit is coupled with the digital processing chip, and the analog equalization circuit comprises an active filter; wherein the read head is used for reading an original analog signal from a magnetic tape of a magnetic tape unit and outputting the original analog signal to the analog equalization circuit; the analog equalization circuit is used for performing data equalization on the original analog signal through an active filter to obtain a first analog signal and outputting the first analog signal to the digital processing chip; the frequency response curve of the first analog signal is closer to the frequency response curve of a target signal type than the frequency response curve of the original analog signal, and the target signal type comprises partial response signals; and the digital processing chip is used for converting the analog signal into a digital signal and processing the digital signal. According to the embodiment of the invention, the order of the digital filter in the magnetic tape unit can be reduced.

The embodiment of the invention provides a magnetic disk device capable of appropriately executing a rewrite operation caused by ATI. A controller of a magnetic disk device according to the present embodiment adds a count value corresponding to a storage region in the vicinity of one of a plurality of storage regions in accordance with a write operation. The rewriting operation includes a seek operation, a stabilization operation waiting for attenuation of residual vibration of the magnetic head, and a rewriting of all data in the first storage area to the first storage area after the stabilization operation. The controller reduces a value of a count corresponding to the first storage area among the plurality of counts in accordance with the rewrite operation. The controller adds a value of a count corresponding to the second storage area among the plurality of counts in accordance with the rewrite operation. The stabilization operation includes an operation for determining whether or not the stabilization operation has been completed on the basis of whether or not a first condition is satisfied. The first condition varies depending on the opportunity of the execution of the retry operation.

To provide a magnetic disk device that can measure PPO correction values with high efficiency.SOLUTION: A plurality of first positions are set in a radial direction of a magnetic disk. The plurality of first positions includes a plurality of second positions and a third position different from the plurality of second positions. A controller of the magnetic disk device measures a RRO (Repeatable RunOut) correction value for each of the plurality of second positions, and executes a first step in which a RRO correction value is not measured for the third position. After the first step, the controller executes a second step in which write or read access is performed on a plurality of tracks. The second step includes acquiring a position error signal by a read head during access and calculating the RRO correction value for the third position based on the position error signal.SELECTED DRAWING: Figure 5

To provide a magnetic recording information processing device that reads information from a magnetic recording medium such as a magnetic card, in which information can be stably read over a wide range of head-to-medium speeds while suppressing cost increases.SOLUTION: A magnetic recording information processing device includes: an AD conversion unit 21 that converts a magnetic reproduction waveform into a digital signal; a memory 22 that accumulates the converted digital signal as data in a first sampling period; a thinning-out processing unit 23 that samples the converted digital signal at a second sampling period that is longer than the first sampling period; a demodulation processing unit 24 that executes a demodulation processing; and a control unit 25 that makes the demodulation processing unit 24 execute the demodulation processing in real-time based on the digital signal sampled by the thinning-out processing unit 23 and makes the demodulation processing unit 24 execute the demodulation processing based on the data accumulated data in the memory when the demodulation processing in real-time fails.SELECTED DRAWING: Figure 1

According to one embodiment, a magnetic disk device includes recording layers, write heads, read heads, a selector circuit that allows two or more read heads to be selected from among the read heads, a read target selection unit, a read processing unit, and a detection unit. When the read target selection unit selects the first recording layer and the second recording layer the read processing unit controls driving of the selector circuit and causes the selector circuit to select the first read head and the second read head to read data of the first recording layer and data of the second recording layer simultaneously, and the detection unit detects a state of the first recording layer and a state of the second recording layer.

To provide a magnetic tape cartridge, a magnetic tape drive, a method of detecting servo patterns, and a program for obtaining a highly reliable servo signal.SOLUTION: In a magnetic tape drive 14, a magnetic tape cartridge 12 includes a magnetic tape MT on which a plurality of servo patterns 58 are recorded in a longitudinal direction and a cartridge memory 24, which is an example of a storage medium. The storage medium stores servo format information SF including servo pattern inclination information SF1 which is information relating to the inclination of the servo pattern with respect to a first virtual straight line.SELECTED DRAWING: Figure 14

To provide a magnetic head and a magnetic recorder that obtain stable characteristics.SOLUTION: A magnetic head 110 includes a reproduction unit 70 including a medium facing surface 10F. The reproduction unit includes first to fourth shields 41-44, and first to third terminals 41T-43T. A first magnetic element 11 is provided between the first shield 41 and the second shield 42 and between the third shield 43 and the fourth shield 44. The first magnetic element 11 includes a first magnetic film 11a, a second magnetic film 11b provided between the first magnetic film 11a and the second shield 42, and a first non-magnetic film 11c provided between the first magnetic film 11a and the second magnetic film 11b. The first non-magnetic film 11c includes at least one selected from the group consisting of Cu, Ru, and Ir. A first non-magnetic film thickness t3 of the first non-magnetic film is 0.1 nm or more and 10 nm or less. The second magnetic film 11b has a second magnetic film thickness t2. A first magnetic film thickness t1 is smaller than the second magnetic film thickness t2.SELECTED DRAWING: Figure 1

The present invention provides a magnetic disk device that can improve the recording density of data on the disk and suppress the degradation of write performance. [Solution] During the first write period, if the determination unit 67 determines that the error correction of the first user data on the first data track has not exceeded the limit, it instructs the write processing unit 62 to continue the write process and the management unit 65 to perform the second management. If the determination unit 67 determines that the above error correction has exceeded the limit, it instructs the write processing unit 62 to continue the write process and the management unit 65 to perform the third management. During or after the first write period, the determination unit 67 instructs the management unit 65 to perform the process of saving the data belonging to the third group to a non-volatile recording medium.

Disclosed are storage devices and methods relating to reading staggered bits recording patterns in which the data bits on adjacent tracks recorded on magnetic media are staggered in such a way that a single reader detects a combined signal from data bits on multiple tracks at selected signal sampling locations. A signal shaping algorithm is used to deconvolve the combine signals, thus isolating each of the tracks from one another so that single track bit sequences can be decoded. In this way, staggered bits patterns can use intertrack interference effects for advantage, allowing readers to read multiple bit tracks simultaneously and without ambiguity.

A magnetic disk device capable of efficiently detecting defects on a disk is provided. [Solution] The magnetic disk device includes a plurality of recording layers L, a plurality of write heads WHD, a plurality of read heads RHD, a selection circuit 3Sb capable of selecting two or more read heads from the plurality of read heads RHD, a read target selection unit 64, a read processing unit 63, and a detection unit 65. When the read target selection unit 64 selects the first recording layer and the second recording layer, the read processing unit 63 controls the driving of the selection circuit 3Sb to cause the selection circuit to select the first read head and the second read head, and simultaneously reads data from the first recording layer and data from the second recording layer, and the detection unit 65 detects the state of the first recording layer and the state of the second recording layer.

According to one embodiment, a magnetic disk device includes a first disk having a first data track and a second data track, a first write head, a write processing unit, an error correction unit, a correction limit prediction unit, and a determination unit. During a write period, the correction limit prediction unit calculates an excess amount, calculates a metric value by multiplying a first weight coefficient by the excess amount, updates a cumulative metric value, and generates first prediction information. The determination unit determines whether or not to allow the write processing unit to continue write processing for the second data track based on the first prediction information.

In an approach to improving write transducers, a write transducer for recording data on a magnetic medium is disclosed. The write transducer includes a first pole piece. The write transducer further includes a second pole piece. The first pole piece and the second pole piece are arranged such that a write gap is formed between the first pole piece and the second pole piece. A longitudinal axis is defined between opposing ends of the write gap. The length of the write gap along the longitudinal axis varies in a direction transverse to the longitudinal axis.

To provide a magnetic reproducing processing device, a magnetic recording / reproducing device, and a magnetic reproducing method capable of suppressing errors.SOLUTION: According to an embodiment, a magnetic reproducing processing device includes a decoder. The decoder includes a convolution layer including a plurality of filters and an attention layer capable of deriving a degree of contribution regarding the plurality of filters. The decoder can output a decoding result obtained by integrating the result of processing the input signal with the plurality of filters according to the degree of contribution.SELECTED DRAWING: Figure 1

Example storage preamplifier circuits, data storage devices, and methods for parallel self-servo write are described. The data storage device may include a pair of preamplifier circuits electrically connected to respective banks of read heads actuated over a storage media surfaces. In read / write operation, each preamplifier circuit may selectively and sequentially provide read signals from a selected head to a pair of read channel interfaces. In self-servo write operation, each preamplifier circuit may selectively and in parallel provide read signals from a selected head in their corresponding banks of read heads to the pair of read channel interfaces. For example, the pair of read channel interfaces for two-dimensional magnetic recording may receive read signals from one read sensor in a head in the first bank of heads and another read sensor for another head in the second bank of heads.

A magnetic disk device and a method for writing a spiral pattern are provided that can improve reliability. The magnetic disk device of this embodiment includes: a disk having a first surface and a second surface different from the first surface; a first head for reading and writing data from and to the first surface; a second head for reading and writing data from and to the second surface; a voice coil motor for moving the first and second heads; and a controller for dividing and writing multiple spiral patterns to be written to one surface of the disk onto the first and second surfaces.