Abstract: A recording head assembly that includes two side-by-side and separately actuated heads. To increase tape capacity while controlling tape mis-registration, write elements are provided in two subsets with a first subset provided on a first of the two heads and a second subset provided on the second of the two heads. The two subsets are offset a distance along the direction of travel for a tape (or horizontal offset) while the two subsets of write elements are also offset along the longitudinal axes of the heads (or bumps on the heads) such that a first subset acts as the upper half of the write element set and a second subset acts as the lower half of the write element set. The subsets of write elements simultaneously writes data, and a similar arrangement can be provided for two subsets of read elements that are aligned with the write elements.

Abstract: Systems and methods (e.g., “utilities”) of measuring errors in the positioning of tape head assembly data write and read elements of a tape drive and utilizing obtained calibration data to accurately align the data write elements with a desired position while writing data tracks and data read elements while reading previously written and aligned data tracks. The disclosed utilities independently determine a degree to which a tape drive write head is to be offset from a nominal write position of the write head over a tape and independently determine a degree to which a tape drive read head is to be offset from a nominal center position of previously written data track of the tape, each to collectively account for the various types of non-idealities in the write or read head of the tape drive (e.g., positioning errors between the data write/read elements and servo readers, etc.).

Abstract: A servo writing method is provided for use with unoriented magnetic tape media. A biasing zone is formed, such as between a pair of permanent block or disk magnets, with a strong DC magnetic field that is substantially free of perpendicular components. The method includes feeding the tape through the magnetic biasing zone to form a longitudinal magnetic bias in the magnetic layer of the tape media. The method includes using a write head to write a servo pattern on the tape media after the forming of the longitudinal magnetic bias in the tape media, and the servo pattern produces an output that is substantially symmetric with high amplitudes. In one embodiment, the biasing zone is formed or defined as the gap between first and second magnetic assemblies oriented with a single direction of magnetization, such as in the same direction as the tape travel through the biasing zone.

Abstract: A servo writing method is provided for use with unoriented magnetic tape media. A biasing zone is formed, such as between a pair of permanent block or disk magnets, with a strong DC magnetic field that is substantially free of perpendicular components. The method includes feeding the tape through the magnetic biasing zone to form a longitudinal magnetic bias in the magnetic layer of the tape media. The method includes using a write head to write a servo pattern on the tape media after the forming of the longitudinal magnetic bias in the tape media, and the servo pattern produces an output that is substantially symmetric with high amplitudes. In one embodiment, the biasing zone is formed or defined as the gap between first and second magnetic assemblies oriented with a single direction of magnetization, such as in the same direction as the tape travel through the biasing zone.

Abstract: In an embodiment, a method is provided for improving signal and transducer alignment in a magnetic tape drive. The method includes writing a first track and a second track to a tape. Each track has an associated track characteristic, which may include fundamental frequency and test binary pattern, among other characteristics. The tracks are adjacent and substantially parallel to one another, and each track has a differing track characteristic value. Each track is read at multiple tracking positions to collect values corresponding to each position. An optimal offset is determined based on the collected values and the corresponding tracking positions. In another embodiment, a magnetic tape drive includes a data reader, a data writer, a processor, and a computer readable medium. The medium has stored instructions, executable by the processor, for carrying out the described method.

Abstract: In an embodiment, a method is provided for improving signal and transducer alignment in a magnetic tape drive. The method includes writing a first track and a second track to a tape. Each track has an associated track characteristic, which may include fundamental frequency and test binary pattern, among other characteristics. The tracks are adjacent and substantially parallel to one another, and each track has a differing track characteristic value. Each track is read at multiple tracking positions to collect values corresponding to each position. An optimal offset is determined based on the collected values and the corresponding tracking positions. In another embodiment, a magnetic tape drive includes a data reader, a data writer, a processor, and a computer readable medium. The medium has stored instructions, executable by the processor, for carrying out the described method.

Abstract: Systems, computer implemented methodology, and computer readable media for measuring position error signal differential nonlinearity in timing based servo patterns. A set of two or more reading heads, positioned at various locations along a servo stripe and orientated transverse to the longitudinal motion of the tape, collect PES data concerning servo stripes. A differential between the two reading heads is examined at various locations along the servo stripe of the servo pattern to ascertain differential PES data regarding an area of interests along the servo stripe. Examination of the differential data is thereafter conducted to isolate systematic PES readings from nonsystematic PES readings. The nonlinearity of the systematic PES readings at the various locations along the servo stripe is measured so as provide the ability to compensate for the nonlinear differential PES associated with the non-ideal shape of servo stripes.

Abstract: Pulses generated from servo stripes of a servo tape system are narrowed by using non-linear gain enabling precise position of the read head. Non-linear gain based on the amplitude of each pulse is applied to each pulse to reduce jitter and distortion so as to more accurately position the read head. A non-linear gain device comprising multipliers apply a non-linear gain to a normal servo pulse signal prior, in one embodiment, to the signal being applied to a qualifier. The non-linear gain device further comprises a limiter so as to limit the gain beyond a certain threshold to 1.0. The limitation of the gain to 1.0 renders the actual amplitude of the pulse unchanged while narrowing the pulse and flattening the baseline. The resulting pulse possesses less jitter and less distortion qualities rendering the positioning of the read head more precise.

Abstract: Systems, computer implemented methodology, and computer readable media for measuring position error signal differential nonlinearity in timing based servo patterns. A set of two or more reading heads, positioned at various locations along a servo stripe and orientated transverse to the longitudinal motion of the tape, collect PES data concerning servo stripes. A differential between the two reading heads is examined at various locations along the servo stripe of the servo pattern to ascertain differential PES data regarding an area of interests along the servo stripe. Examination of the differential data is thereafter conducted to isolate systematic PES readings from nonsystematic PES readings. The nonlinearity of the systematic PES readings at the various locations along the servo stripe is measured so as provide the ability to compensate for the nonlinear differential PES associated with the non-ideal shape of servo stripes.

Abstract: Method and system of measuring and optimization of noise in a servo system. The method and system including features to optimize filtering otherwise reducing noise in the system so as to permit improved system operation.

Abstract: Pulses generated from servo stripes of a servo tape system are narrowed by using non-linear gain enabling precise position of the read head. Non-linear gain based on the amplitude of each pulse is applied to each pulse to reduce jitter and distortion so as to more accurately position the read head. A non-linear gain device comprising multipliers apply a non-linear gain to a normal servo pulse signal prior, in one embodiment, to the signal being applied to a qualifier. The non-linear gain device further comprises a limiter so as to limit the gain beyond a certain threshold to 1.0. The limitation of the gain to 1.0 renders the actual amplitude of the pulse unchanged while narrowing the pulse and flattening the baseline. The resulting pulse possesses less jitter and less distortion qualities rendering the positioning of the read head more precise.

Abstract: Identification of servo tracks is provided by adding one or more additional symbols to the write elements of at least some tracks on a servo recording head. The additional symbols are ignored for timing purposes, as they are not necessarily symmetrical, but the added symbols provide identification by their alterations on the otherwise identical patterns.

Abstract: A method for correcting data track placement in a magnetic tape drive is provided. The invention comprises writing at least one data track on a magnetic tape, wherein the data track is written in a location determined by tracking a servo track on the tape. The tape drive reads the data track(s) at a plurality of offset positions, wherein each offset position is determined by deviating the servo track a specified distance from a servo reader. An optimal offset position is then determined based on collected read error data versus offset position data. During subsequent write operations, tapes are offset according to the optimal offset position.

Abstract: A servo track write head writes low frequency transitions for fine transverse positioning and high frequency fields providing additional information. The servo track write head includes a first write gap with at least one gap section at a first angle relative to a tape direction. A second write gap has at least one gap section at a second angle, not equal to the first angle. The first and second write gaps write low frequency transitions in each servo frame. A third write gap writes high frequency transitions in each servo frame.

Abstract: Servo tracks combine low frequency transitions for fine transverse positioning with high frequency fields providing additional information. In one embodiment, each servo frame has a first field of recorded low frequency transitions, a second field of recorded low frequency transitions, and at least one high frequency field. The first low frequency field transitions are recorded on the tape such that a peak of each first field transitions varies in longitudinal position across the width of the servo frame. The second field of low frequency transitions are recorded on the tape such that a peak of each second field transition is not parallel with the peak of any first field transition. High frequency fields may provide one or more of timing information, longitudinal position information and gross transverse position information.

Abstract: Identification of servo tracks is provided by adding one or more additional symbols to the write elements of at least some tracks on a servo recording head. The additional symbols are ignored for timing purposes, as they are not necessarily symmetrical, but the added symbols provide identification by their alterations on the otherwise identical patterns.

Abstract: Servo tracks combine low frequency transitions for fine transverse positioning with high frequency fields providing additional information. In one embodiment, each servo frame has a first field of recorded low frequency transitions, a second field of recorded low frequency transitions, and at least one high frequency field. The first low frequency field transitions are recorded on the tape such that a peak of each first field transitions varies in longitudinal position across the width of the servo frame. The second field of low frequency transitions are recorded on the tape such that a peak of each second field transition is not parallel with the peak of any first field transition. High frequency fields may provide one or more of timing information, longitudinal position information and gross transverse position information.

Abstract: A servo track write head writes low frequency transitions for fine transverse positioning and high frequency fields providing additional information. The servo track write head includes a first write gap with at least one gap section at a first angle relative to a tape direction. A second write gap has at least one gap section at a second angle, not equal to the first angle. The first and second write gaps write low frequency transitions in each servo frame. A third write gap writes high frequency transitions in each servo frame.

Abstract: Positioning of a tape head relative to a magnetic tape may be improved through accurate measuring of magnetic tape position error. The tape head includes at least one read module having two servo read elements. A head control detects the presence of corresponding synchronization fields passing the servo read elements. The elapsed time between the detected synchronization fields is determined. Tape skew is calculated based on the elapsed time. Tape position error calculation may be further improved by including another servo read element on either a second read module or a write module. Tracking information read from two servo read elements scanning the same servo stripe is used to calculate the offset between a read module and the write module.

Abstract: A method of attaching a tape having longitudinal edges to a tape cartridge reel includes cutting an end of the tape non-perpendicularly to the longitudinal edges laterally across the width of the tape. The end of the tape is then attached to the tape cartridge reel. The method may also include cutting an end of the tape such that at least two of the laterally spaced apart servo stripes running longitudinally along the tape are cut at different longitudinal positions along the tape. The method may further include cutting the tape end such that at least two of the laterally spaced apart data tracks running longitudinally along the tape are cut at different longitudinal positions along the tape.