Abstract: A data-storage disk includes a disk sector for storing data and a servo wedge located at the beginning of the sector. The servo wedge indentifies the sector in conjunction with both an initial positioning of a read-write head and a data read or write operation. By using a servo wedge to provide both an initial head position on disk spin up and a head position during a read or write operation, one can increase a disk's data-storage capacity by reducing the number of, or altogether eliminating, spin-up wedges.

Abstract: The invention is directed to techniques for erasing data storage tape for reuse. In an embodiment, an erase head module for erasing data storage tape comprises a set of erase gaps and one or more servo read elements. The set of erase gaps is configured to coincide with data bands of the data storage tape to allow erasure of only the data bands of the data storage tape while not erasing servo bands of the data storage tape. The one or more servo read elements detect one of the servo bands of the data storage tape when the set of erase gaps are proximate the data bands of the data storage tape to allow the erase head module to accurately track the data bands with the set of erase gaps.

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.

Abstract: A detector recovers servo data from a servo signal generated by a read-write head, and determines the head-connection polarity from the recovered servo data. Such a detector allows a servo circuit to compensate for a reversed-connected read-write head, and thus allows a manufacturer to forego time-consuming and costly testing to determine whether the head is correctly connected to the servo circuit.

Abstract: A method for detecting errors in a servo system of a magnetic storage drive includes writing a plurality of data tracks at a pitch, detecting a position of an edge of at least two of the data tracks under control of a servo system (e.g., an optical or magnetic servo system), and determining an error in the servo system based on the detected positions and known pitch of the data tracks. Differences in the track edge positions of the tracks from the positions at which they were written may indicate errors in the optical servo system (e.g., non-linearity errors, as well as other errors such as electrical, temperature, or the like). Determined errors may be stored with a look-up table of positional errors or used to normalize a position algorithm associated with the servo system.

Abstract: Provided are a read channel, storage drive and method using a measured error to determine coefficients to provide to an equalizer to use to equalize an input signal. A read channel is incorporated in a storage device to process signals read from a storage medium. An equalizer uses coefficients to equalize input read signals to produce equalizer output signals. A detector processes adjusted equalizer output signals to determine output values comprising data represented by the input read signals. An equalizer adaptor is enabled to provide a reference measured error and coefficients used to produce the adjusted equalizer signals that are associated with the reference measured error. The equalizer adaptor computes new equalizer coefficients to use to equalize input read signals that result in a new measured error from the detector and computes a new measured error for the new equalizer coefficients.

Abstract: A storage channel, e.g., for a disk drive system, may asynchronously sample and buffer an entire sector, and then process the buffered sector to recover timing information. The storage channel may operate in an open-loop and utilize an exhaustive search to determine timing parameters. Alternatively, the storage channel may operative in a closed-loop, processing the sector once, and feeding back information obtained during decoding to the timing loop.

Abstract: A method is provided. The method includes determining that a data sector included in a select data track is in error, the data sector in error includes at least one identified data wedge. The at least one defective data wedge in the data sector in error is located. The method also includes moving the at least one defective data wedge by utilizing at least one spare wedge on the select data track.

Abstract: A system and method to avoid disk lube pooling is presented. A track access monitor tracks the number of times that a program accesses a particular track located on a hard drive. When the track access monitor determines that the number of track accesses to a particular track exceed a track access threshold, the track access monitor invokes a sequence of events to scan adjacent tracks in order to uniformly redistribute lubrication over the hard drive. In one embodiment, the track access monitor incrementally performs the adjacent track scanning during hard drive idle periods, such as when the system waits for a password from a user or when the operating system conserves power and idles the hard drive due to lack of activity.

Abstract: A read-channel module includes a variable-gain amplifier (VGA) module, an analog-to-digital converter (ADC) module, an amplitude measuring module, a gain adjusting module, and a zero phase start (ZPS) module. The VGA module has a variable gain, amplifies input signals, and generates amplified signals. The ADC module converts the amplified signals from analog to digital format and generates samples. The amplitude measuring module receives N of the samples and measures amplitudes of the N samples, where N is an integer greater than 1. The gain adjusting module communicates with the amplitude measuring module and selectively adjusts the variable gain of the VGA module based on the amplitudes. The zero phase start (ZPS) module communicates with the amplitude measuring module, receives the samples, and selectively generates phase information from the samples based on the amplitudes.

Abstract: Systems and techniques relating to interpreting signals on a channel having an asymmetrical signal amplitude response can include generating multiple asymmetry matrices that model asymmetry in a received analog signal, including an effect of asymmetry spreading in a read channel; comparing the multiple asymmetry matrices; and selecting indicators of asymmetry from the matrices based on the comparing. Systems and techniques can include saving in memory an indication of the selected indicators of asymmetry.

Abstract: To effectively suppress a signal in a low frequency region in which the medium noise and the signal distortion are concentrated, and in order to effectively utilize a detected component of the reproduced signal in the low frequency region, a target of partial response equalization to the perpendicularly recorded/reproduced signal is set so that the low-frequency component around the direct current is suppressed to a regulated quantity for both the effective suppression and the effective utilization. Accordingly, a maximum-likelihood decoding process is carried out through the target of partial response equalization. Reliability of data detection is made higher and a signal-to-noise ratio is improved, so that the noise from the recording medium can be reduced more and it is possible to provide a high-density magnetic recording/reproducing apparatus.

Abstract: A thermally assisted magnetic recording system is provided to achieve excellent thermal resistance and low noise. In one embodiment, a magnetic recording medium is used, in which the magnetic intergrain exchange coupling is large to let the magnetization be thermally stable by coupling the magnetic grains constituting the recording layer at room temperature (the temperature maintaining the magnetization) and reduced by heating during recording to let the recording magnetization transition slope become steep. Parameter A normalizing the slope around the coercivity of the MH-loop of the medium is 1.5?A<6.0 at room temperature, and it becomes approximately 1.0 with heating.

Abstract: A mechanical transport device includes a system for transport; and a hard disk drive attached to the system. The hard disk drive comprises a magnetic recording disk to record data, a head to read or write the data to or from the disk, and a drop sensor designed to sense a shock condition. The system for transport may be a vehicle such as a car. Additional systems are also presented.

Abstract: Methods and recording systems are configured for recording different data simultaneously at two different depths of a tilted magnetic medium, the tilted magnetic medium having a hard axis of magnetization, the axis being out of a plane of the medium and at an angle of ?10 to ?80 degrees with respect to a direction along which data are recorded, the medium being capable of having two depths of recording. A method embodies writing with selected magnetic fields whose amplitudes and whose angles with respect to the medium hard axis direction differ at the two depths of the medium such that the recorded direction of magnetization at the respective two depths can be set independently.

Abstract: Embodiments of the present invention provide a magnetic disk drive capable of controlling write/read positions by a method that takes the disturbance in the circumferential direction of a magnetic disk into consideration, thereby making it possible to improve the positioning accuracy. A magnetic disk drive in accordance with an embodiment of the present invention comprises: a magnetic recording medium on which information is written to each track thereof, the recording medium having a servo signal formed in the each track at specified intervals; a magnetic head including a read head for reading a signal from the magnetic recording medium, and a write head for writing information to the magnetic recording medium. At the time of writing/reading information by the magnetic head, a servo signal is detected from among signals read out by the read head.

Abstract: A master-disk producing device produces a master disk with master-disk identification information added. A disk producing device produces a first disk with the master-disk identification information added, using the master disk with the master-disk identification information added. A first disk device obtains, after the first disk with the master-disk identification information added is mounted, first correction information from a correction-information storing device based on the master-disk identification information of the first disk.

Abstract: An optical data-storage hard disk drive that uses stationary Phase-Change Microhead Array Chips in place of conventional flying-heads, rotary voice-coil actuators, or other similar types of servo-tracking mechanisms to simultaneously record and/or reproduce data to and/or from a multitude of data-tracks located across the data-surfaces of a multitude of phase-change based disc media using a multitude of microheads.

Abstract: A sample and hold circuit is disclosed that provides longer hold times. The sample and hold circuit can be used in a disc drive to provide improved read-to-write and write-to-read mode transitions. The sample and hold circuit has an input and an output, and includes at least one capacitive element for retaining a charge. The capacitive element is connected to a node between the input and the output. The sample and hold circuit includes at least one input switch to selectively connect the capacitive element to the input and at least one output switch to selectively connect the capacitive element to the output. In addition, an amplifier is connected to the node and has an offset voltage. In this manner, a voltage drop across at least one of the input and output switches is limited to the offset voltage.

Abstract: An apparatus for producing an optical spot on the order of 25 nm in a recording media. The apparatus includes an optical transducer comprising a waveguide which defines an aperture adjacent to an air bearing surface of the transducer adjacent a recording media. The transducer includes a protrusion extending beyond the plane of the air bearing surface extending toward the recording media.