Abstract: A disk drive is disclosed comprising a head actuated over a disk, and a spindle motor operable to rotate the disk. A baseline relationship is generated between a baseline current draw of the spindle motor over a temperature range. An operating current draw of the spindle motor is measured and a corresponding operating temperature is measured. Failure of the spindle motor is predicted based on the operating current draw, the operating temperature, and the baseline relationship.

Abstract: A read channel is configured to receive at least part of a data fragment read from a storage media into a register, wherein the data fragment is configured to be formatted with a preamble, a sync mark (e.g., a syncMark), and user data, and wherein the data fragment is missing a sync mark. A position in the data fragment is selected, a sync mark is assumed at the selected position. The data is then processed assuming the sync mark is at the selected position of the data fragment to determine whether the data converges. When a determination is made that the data converges, the data is recovered.

Abstract: Systems, circuits, devices and/or methods related to systems and methods for data processing, and more particularly to systems and methods for media defect detection.

Abstract: Methods and apparatus are provided for improved detection of servo sector data in a magnetic recording system using single bit error correction. Servo sector data is processed by detecting the servo sector data; determining whether a single bit error occurred in the detected servo sector data; and flipping a bit value of an individual bit in the detected servo sector data having a lowest amplitude sample among the samples of the detected servo sector data when a single bit error is detected in the detected servo sector data. The servo sector data comprises, for example, a servo address mark, Gray data, an RRO address mark and/or RRO data. For example, the bit value can be flipped by changing a binary value of one to a binary value of zero and changing a binary value of zero to a binary value of one.

Abstract: A method of storing data in a storage medium includes determining a compensation unit for a portion of the storage medium, reading a first set of bit values from the portion of the storage medium, determining a compensation value based at least in part on an erroneous bit value of the first set of bit values and the compensation unit, and storing the compensation value in association with the portion of the storage medium.

Abstract: Various embodiments of the present invention provide systems and methods for determining contact between a head and a storage medium.

Abstract: According to one embodiment, there is provided a method for determining whether a defect on a disk in an apparatus includes head is a recess or a protrusion. The method detects a first defect on the disk using a read element provided in the head. The method detects a second defect on the disk using a head disk interference sensor provided in the head. The method further determines whether a third defect is a recessed defect or a protruding defect based on a ratio between a first width of the first defect in a radial direction on the disk and a second width of the second defect in the radial direction of the disk. The third defect is identified based on the first defect and the second defect.

Abstract: A method, apparatus, and system are provided for implementing magnetic defect location detection on-the-fly for hard disk drives. A magnetic media readback signal of a hard disk drive is demodulated to generate phase modulation (PM) and amplitude modulation (AM) signals. A new coordinate plane defined by a combined phase modulation (PM) and amplitude modulation (AM) phasor-defect detector calculation function used to locate magnetic defects on-the-fly.

Abstract: In one embodiment, a tape drive system includes a soft detector for executing a first forward loop of a detection algorithm on a first block of signal samples during a first time interval; and logic for executing forward and reverse loops during several time intervals; and logic adapted for outputting a first decoded block of signal samples based on the executing the decoding algorithm on the first block during a sixth time interval, wherein a sum of second, third, fourth, fifth, and sixth time intervals are about equal in duration to the first time interval.

Abstract: In one embodiment, a tape drive system includes a read channel, a write channel, logic adapted for accessing data sets using the read channel and/or the write channel, logic adapted for counting each data set access using the read channel that used error recovery procedure (ERP), logic adapted for counting each data set access using the read channel that did not use ERP, logic adapted for counting each data set access using the write channel that used ERP, logic adapted for counting each data set access using the write channel that did not use ERP, and logic adapted for accessing subsequent data sets using the read channel and/or the write channel, wherein any subsequent data set access that uses ERP is accessed using an initial ERP step characterized by a first tape speed, wherein the first tape speed is selected at least partially based on the counts.

Abstract: The disclosure is related to systems and methods for servo Gray code error detection and correction. A device may include a circuit configured to 1) selectively implement a quality-based error correction system to determine an error in the servo Gray code and correct the error; 2) selectively implement a trajectory-based error correction system to determine an error in the servo Gray code and correct the error; or 3) implement any combination of a quality-based error correction system and a trajectory-based error correction system to determine an error in the servo Gray code and correct the error.

Abstract: Various embodiments of the present invention provide systems and methods for data processing. For example, a data processing system is disclosed that includes: a data detector circuit, a filter circuit, and a mean squared calculation circuit. The data detector circuit is operable to apply a data detection algorithm to a data set to yield a detected output. The filter circuit is operable to filter the detected output to yield a filtered output. The mean squared calculation circuit is operable to calculate a mean squared error value based at least in part on the data set and the filtered output. A quality indicator is generated at least in part on the mean squared error value.

Abstract: A method for selecting which tap coefficients of a programmable finite-impulse-response (FIR) equalizer to fix is disclosed. In one embodiment, such a method includes performing an initial calibration to determine an initial value for each tap coefficient of a FIR equalizer. These initial values may be used to produce a first waveform. The method then performs an operation on the first waveform to produce a second waveform comprising multiple lobes. The second waveform is then analyzed to determine one or more lobes of the second waveform that have the largest area. The method then fixes coefficients of one or more taps that are closest to the lobe or lobes having the largest area. A corresponding apparatus and computer program product are also disclosed.

Abstract: An information recording/reproducing device capable of recording or reproducing information to or from a plurality of information recording media, includes a plurality of information recording/reproduction drives which can record or reproduce the information recording media and during recording or reproduction, can measure information recording medium quality evaluation item values representing values indicative of qualities of the information recording media; and an information recording medium monitor which can calculate tendency to quality degradation of the information recording medium from information recording medium quality evaluation item values preserved by an information recording medium monitoring database which can preserve the measured information recording medium quality evaluation item values. The information recording medium monitor is capable of calculating from a tendency to quality degradation of an arbitrary information recording medium the quality of another information recording medium.

Abstract: A method, apparatus, and system are provided for implementing magnetic defect classification using phase modulation for hard disk drives. A magnetic media readback signal of a hard disk drive is processed to identify predefined phase modulation (PM) characteristics to implement magnetic defect classification of magnetic media bump and pit defects.

Abstract: A data recovery device including a filter, a tilt detection unit, a tilt cancellation unit and a data conversion unit is provided. The filter filters a radio-frequency data stream to generate an original data stream. The tilt detection unit synthesizes a tangential push-pull data stream by employing a first to a fourth data streams, and generates a tilt direction signal according to symmetry of a curve composed by the tangential push-pull data stream. The tilt cancellation unit detects a plurality of rising areas and falling areas of the original data stream, and reconstructs a plurality of data points corresponding to the rising areas or falling areas in the original data stream so as to generate a tilt repair data stream. The data conversion unit recovers the tilt repair data stream to a modulation signal.

Abstract: A change in a property of a signal is detected, the signal having been sensed from a storage medium by a disk drive. A count is determined, the count corresponding to a first location on the storage medium at which the change in the property of the signal sensed from the storage medium is detected. The count is used to predict a second location on the storage medium corresponding to the change in the property of the signal sensed from the storage medium. Relative to the first location on the storage medium, the second location on the storage medium is closer to an actual location of a feature on the storage medium that causes the change in the property of the signal sensed from the storage medium.

Abstract: A system and method of calibrating optical measuring equipment includes optically measuring discrete objects of a first known predictable pattern from a calibration apparatus, wherein the first known predictable pattern is a bit pattern. A recording surface optical reader is calibrated based on the optically measuring. Using the first known predictable pattern, contamination is filtered from the results of the optically measuring.

Abstract: Various embodiments of the present invention provide systems and methods for calculating and/or modifying fly height. For example, a circuit for calculating fly height is disclosed that includes: a first pattern detector circuit, a second pattern detector circuit, a first pattern fly height calculation circuit, a second pattern fly height calculation circuit, a first averaging circuit, a second averaging circuit, and a combining circuit.

Abstract: Optically detectable marks readable by a wide range of optical systems are included on an optical storage medium. Among other uses, the marks may be used to determine the type of the optical storage medium in an optical device capable of reading multiple types of optical storage media.

Abstract: An optical pickup device includes a light source for emitting a light beam, an objective lens for collecting the light beam which is emitted and for irradiating an optical disc with the collected light beam, a diffraction element with a plurality of areas for dividing the light beam which is reflected from the optical disc, a detector with a plurality of detection parts for receiving the light beam which is made to diverge by the diffraction element, and a branching mirror for making the light beam branch into an optical path from the light source to the objective lens and an optical path from the objective lens to the detector. The diffraction element gives an aberration to the light beam diffracted at a specified area.

Abstract: A tape cartridge library that is equipped with a cleaning device is described. The tape cartridge library essentially includes a plurality of tape cartridges each possessing recording tape media. A plurality of tape drives that read and write data to and from each of the tape cartridges. A tape cleaning drive incapable of transferring data to and from the recording tape media which is independent of the tape drives, the tape cleaning drive disposed entirely within the tape cartridge library. The tape cleaning drive automatically receives one of the tape cartridges and cleans its respective recording tape medium when a predetermined reason for cleaning the tape cartridge is justified.

Abstract: The present invention accurately operates a tilt servo even if a gap servo is operated with a small gap.

Abstract: A method for recovering data from a failed tape cartridge is presented. The reliability of a tape cartridge is assessed via the number of read errors encountered. If the number or read errors is excessive, the tape cartridge is deemed unreliable and the tape cartridge is restricted from storing anymore data. A search is performed to look for duplicate data and if found a copy of the duplicate data is stored to a replacement tape cartridge. The replacement tape cartridge assumes all identity of the original failed tape cartridge.

Abstract: An optically-readable disk includes a device that disrupts readability of the disk when the disk is spun at an angular velocity substantially greater than required to play the disk in its intended playing device, or when a defined integral of velocity and time is exceeded. The device may include a fluid container that disperses a data-disruptive fluid. The device may include a membrane or layer that is disrupted when the disk is rotated above a defined angular velocity, or when a defined integral of velocity and time is exceeded. The device may include an electro-optical material that is activated by an electrical signal from a controller in response to an input from a sensor responsive to motion of the disk.

Abstract: A technique capable of realizing a power saving in a device for reproducing/recording digital signals by controlling a frequency of a clock. The device for reproducing/recording digital signals includes: a difference comparing circuit for comparing a first parameter updated each time a process for one correcting block is done in a demodulating circuit with a second parameter updated each time a process of one correcting block is done in an error correcting circuit; and a circuit for switching a frequency of a master clock depending on a comparison result of the difference comparing circuit. Thereby, the frequency of the clock can be switched both when the demodulation for one correcting block is ended and when the correcting process for one correcting block is ended by using the switched master clock.

Abstract: The data recording apparatus for recording data to a recording medium having one or more tracks arranged in parallel comprises a data recorder configured to record data to the one or more tracks, a memory configured to store data, and a controller configured to control the data recorder. The controller determines whether or not the one or more tracks include a data defective region in which the data has not been recorded properly, stores in the memory the data that has not been recorded properly, designates a position corresponding to the data defective region, which is in a track arranged in parallel to the data defective region, and reads from the memory the data that has not been recorded properly, and records that data to the position corresponding to the data defective region.

Abstract: An optical disc device and a recording method is provided in which information can be additionally recorded on an optical disc, which has a servo layer and recording layers separately formed, by accurately correcting a relative angle between a light beam and the optical disc used in the previous recording without providing an area where recording is not performed while maintaining the stability of tracking servo. The above subject can be solved by studying with high accuracy the relative angle between the optical disc and the optical axis used in the previous recording by applying a radial tilt servo according to a signal from the recording layers with the tracking servo applied by the servo layer. Further, the additional recording can be performed stably by fixing the radial tilt at the previously studied angle when the recording is performed.

Abstract: A media processing system enables producing a copy of media based on the state of media deterioration. An error rate measurement unit measures the error rate of recorded media after specific data is written to the media; an error rate evaluation unit determines if the media error rate measured by the error rate measurement unit is less than or equal to a preset threshold value; and a data recording unit that, when the error rate evaluation unit determines the error rate exceeds the specific threshold value, writes specific data recorded to the recorded media to other unused media.

Abstract: A semiconductor integrated circuit is equipped with a reproduction ECC circuit, a recording ECC circuit, a host interface circuit, and a memory control circuit. The memory control circuit includes an arbitration circuit and a count circuit. The arbitration circuit arbitrates ECC access with a priority order higher than the access of a host interface with a host apparatus. The count circuit counts the number of output times of the ECC request, and, when the count reaches a prescribed number, the count circuit generates a count termination signal. The arbitration circuit performs switching of priority orders to arbitrate the host with a priority order higher than that of ECC. The prescribed number corresponds to number of output times of the ECC access request necessary for accessing a semiconductor memory in relation to data of one ECC block or of an integral multiple of the one ECC block.

Abstract: A semiconductor device mounted in an optical disk apparatus controls writing and reading of data in and from an optical disk. The device performs first processing for adjusting a write strategy in such a manner that based on error information corresponding to a shift in the phase of a reproduction signal with respect to a channel clock signal for data reproduction, which is generated based on the reproduction signal read from the optical disk, the value of the error information related to a plurality of recording marks to be evaluated becomes minimum as a whole. The device also performs second processing for adjusting a write strategy in such a manner that the value of the error information related to a desired recording mark becomes small.

Abstract: A data signal comprising an even component and an odd component with differing amplitudes is received at a main automatic gain controller (AGC). The even component is adjusted by a first interleaved AGC and the odd component is adjusted by a second interleaved AGC such that even and odd component amplitudes are substantially equal. Amplitude adjusted even and odd components are recombined to define a data signal with components having substantially equal amplitudes. The even and odd components can be generated by a read transducer moving relative to a magnetic storage medium comprising tracks defined by discrete and spaced-apart recording bits arranged in an interspersed pattern. A read channel separates the data signal into even and odd samples such that a gain can be independently adjusted for each of the even and odd samples to compensate for asymmetry between the even and odd samples.

Abstract: In an optical pickup device for a simple optical system, a light beam emitted from a laser diode is split into first and second light beams by a polarized beam splitter, an optical disc is irradiated with the first light beam to obtain signal light, and the second beam is reflected by a reflection element to obtain reference light. Light beams of the signal light and the reference light are synthesized into one light beam, the synthesized light beam is separated into four light beams by a phase difference forming unit including a grating, a divided wave plate and a polarization grating, and different phase differences are afforded to the signal light and the reference light in each light beam. The four light beams are detected by one detector to generate the reproduction signal.

Abstract: Aspects of the disclosure provide a method for detecting land pre-pits. The method includes extracting a land pre-pit data stream from a signal responsive to land pre-pits on an optical medium based on a land pre-pit threshold, detecting a bit stream pattern from the land pre-pit data stream, comparing one or more bits in the land pre-pit data stream at locations relative to the bit stream pattern with pre-known bit information, and adjusting the land pre-pit threshold based on the comparison.

Abstract: A write-once disc includes: a plurality of update areas in which a predetermined kind of updated information is recorded; at least one main access information area in which main access information is recorded, the main access information indicating a final update area in which finally updated information is recorded among the plurality of update areas; and at least one sub access information area in which sub access information is recorded, the sub access information indicating a location of the finally updated information recorded in the final update area. Accordingly, an access time for reading a predetermined kind of information required to use the write-once disc can be reduced.

Abstract: A channel circuit includes: a detecting module configured to sample a signal amplitude of a reproduced signal of a single-frequency pattern written on a medium, and to detect an amplitude change that is lower or higher than a threshold; and a judgement module configured to judge whether the reproduced signal is decodable by a decoding circuit or not based on a result of detection by the detecting module.

Abstract: An information correcting method includes: detecting a first pattern in a radial direction and a second pattern formed obliquely to the radial direction on a track traversing the first and second patterns; counting number of the first pattern until the count value reaches number of the first pattern in one round of the track; generating a value incremented up number of the second pattern in the one round every time an interrupt associated with detection of the second pattern is generated as number of the second pattern; calculating an ideal number from a value obtained by multiplying the number of the second pattern until the number is counted by the counted number of the detected first pattern and a number set to the second pattern with reference to the second pattern formed at a present initial position; and correcting the generated number with the ideal number.

Abstract: An information recording processing constitution realizing both readout difficulty and high-precision readout is provided. Superimposition recording of highly secret additional information such as a cryptographic key in a groove signal recorded on a disk, which superimposition recording realizes both readout difficulty and high-precision readout, can be performed. The groove signal to which a phase error corresponding to a bit value is set is recorded at a time of recording of the additional information, and at a time of readout of the additional information, the phase error of the groove signal in a predetermined section is subjected to an integrating process and the direction of the phase error of the groove signal within each section is determined. The recording and reproduction of the additional information for increasing readout difficulty and realizing high-precision readout is realized by such processes.

Abstract: An information recording medium, and a recording/reproducing apparatus and a recording/reproducing method for the recording medium. Original data is sequentially updated by replacing an original recording block with one or more replacement recording blocks. A replacement recording block includes at least one of an original address field indicating a location of the original recording block or a previous address field indicating a location of an immediately previous recording block. Replacement information is effectively recovered in a system where a replacement for logical overwriting (LOW) occurs in either a spare area and a user data area by reference to the address fields in each replacement recording block.

Abstract: Various embodiments of the present invention provide systems and methods for medium utilization control. As an example, a method for identifying potentially damaged media regions is discussed that includes receiving a data set; performing a data detection process on the data set to yield a detected output and a status value corresponding to the data set; performing a data decoding process on the detected output to yield a decoded output; and identifying a region of a storage medium from which the data set was derived as failing based at least in part on the status value.

Abstract: A disc inspecting method includes: forming recording marks on a disc; scanning the recording marks from inside to outside or from outside to inside of the disc by a pickup unit to read a reproduction signal while rotating a spindle to move a slider by each predetermined width; acquiring reproduction data from the reproduction signal in a signal acquiring unit; and determining whether or not the reproduction data is proper in a calculation unit, and optimizing a formation condition of the recording marks when it is determined that the reproduction data is not proper.

Abstract: An information recording device includes: a magnetic disk; an identify module; and a record module. The magnetic disk includes information tracks for recording information by a shingle recording method and an alternate track including an alternate sector for recording alternate information. The identify module is configured to identify a track group including the information tracks that includes update sectors for updating information and a defective sector. The record module is configured to perform recording for updating information on the identified track group without updating the alternate information of the alternate sector corresponding to the defective sector.

Abstract: A reproducing apparatus is provided. The reproducing apparatus includes a recording/reading unit that records data on or reads data from a disc including a defect management area in which defect information regarding data recorded in a data area of the disc and defect management information for managing the defect information are repeatedly recorded, and a controller that controls the recording/reading unit to read the defect information and the defect management information from the defect management area, and read data from the disc using the defect information. First defect information, which is repeatedly recorded, includes second defect information which is recorded in a predetermined area and defect information regarding a defective block occurring after the second defect information is recorded. The defect management information includes location information of the defect information.

Abstract: A method for detecting a typical defect area on a disc track includes the following steps. Firstly, a source signal is provided. Then, first and second signals are generated according to the source signal. The first and second signals are held at the peak level of the source signal and respectively decreased at first and second drop rates. Then, first and second threshold values are subtracted from the first and second signals to generate first and second slice signals, respectively. Afterwards, the source signal is compared with either the first slice signal or the second slice signal. When the first slice signal is larger than the source signal, a typical defect signal is changed from a first level to a second level. Whereas, the typical defect signal is changed from the second level to the first level when the second slice signal is smaller than the source signal.

Abstract: An instantaneous jitter information detection section detects, based on first and second digital values indicating different polarities relative to a predetermined reference value, an instantaneous gradient value corresponding to a difference value between the first and second digital values, and an instantaneous deviation value corresponding to a difference value between an intermediate value between the first and second digital values and the reference value. An information conversion section converts, based on an inversely proportional conversion table, the instantaneous gradient value to an inversely proportional value. An arithmetic section detects an instantaneous variance value by multiplying the instantaneous deviation value and the inversely proportional value together, and squaring a value obtained by the multiplication, and detects an integrated value by accumulating the instantaneous variance value.

Abstract: Provided is an optical disc device capable of correcting a value of a control parameter during an operation of reading information from an optical disc medium. The optical disc device for reading the information recorded on the optical disc medium under an operation condition corresponding to a value set with respect to a predetermined control parameter corrects the value of the predetermined control parameter by repeatedly executing, while an operation of reading the information from the optical disc medium is being performed, processing of: acquiring, with respect to two values of the predetermined control parameter, evaluation values indicating accuracy of the reading of the information from the optical disc medium, respectively; and updating the value of the predetermined control parameter based on the two acquired evaluation values.

Abstract: An exemplary data recording method of an optical storage medium includes following steps: during a current recording operation for recording first data onto the optical storage medium, detecting if a fatal recording error occurs; and when the fatal recording error is detected, activating a current verifying operation to verify correctness of a recorded data section on the optical storage medium. The recorded data section is recorded onto the optical storage medium according to second data during a previous recording operation, and data recording of the second data has been verified during a previous verifying operation prior to the current recording operation.

Abstract: According to one embodiment, a non-linearity measurement apparatus includes a first measurement module, a second measurement module, and a calculation module. The first measurement module is configured to measure a component of a first higher harmonic from a reproduced signal of a first signal recorded on a magnetic recording medium. The second measurement module is configured to measure a component of a second higher harmonic from a reproduced signal of a second signal recorded on the magnetic recording medium. The calculation module is configured to calculate a non-linear transition shift of the magnetic recording medium by calculating an arcsine function of a value obtained by dividing the component of the second higher harmonic by the component of the first higher harmonic.

Abstract: A recording device includes: a recording and reproducing unit that records or reproduces data stored on a recording medium; and a control unit that interrupts recording during recording performed by the recording and reproducing unit, acquires an evaluation value of a recording quality of a recorded portion, changes recording speed based on the evaluation value, and resuming the recording.

Abstract: A method for detecting the obliquity of an optical disc drive is provided. The method includes the steps of calibrating balance gains of TE signals and CE signals with predetermined obliquities of the optical disc drive, curve-fitting and storing a relating function between the predetermined obliquities and the balance gains, calibrating the balance gains of signals for an installed optical disc drive, and acquiring an calibrated balance gain to find the obliquity of the optical disc drive from the relating function.