JP2009032373A - Track format, recording medium, recording apparatus, recording method, reproducing apparatus, reproducing method, and recording / reproducing apparatus - Google Patents

Abstract

Even when there is a deviation of a reproducing head with respect to a track, it is possible to satisfactorily perform signal separation arithmetic processing.
A magnetic recording medium in which data and a preamble including an identification pattern and a separation pattern capable of identifying the track are recorded on a plurality of tracks constituting a unit which is a unit of signal processing for data reproduction. Is reproduced, the identification pattern for each track is detected from the signal reproduced by the reproducing head to obtain track identification information. In consideration of this track identification information, the start position of the separation pattern for each track is specified , a channel matrix is calculated based on the reproduction signal of the separation pattern for each unit, and playback is performed by the playback head using this channel matrix. The reproduced signal of the data for each track is separated from the reproduced signal for one unit.
[Selection] Figure 3

Description

  The present invention relates to a track format, a recording medium, a recording apparatus, a recording method, a reproducing apparatus, a reproducing method, and a recording / reproducing apparatus capable of reproducing data by a reproducing apparatus having a reproducing head capable of reproducing a signal across a plurality of tracks. .

  In recent years, magnetic heads are required to have higher density recording in order to increase the capacity of magnetic recording media, and are suitable for narrowing the track width of tracks (hereinafter referred to as “narrowing”). Magnetic heads have been adopted. In general, improving the accuracy of the track servo is the key to narrowing the track.

  In a magnetic tape recording / reproducing apparatus, a so-called non-tracking system has been proposed as a countermeasure for making servo difficult as the width becomes narrower, and has been put into practical use (for example, Patent Documents 1-5). In this non-tracking method, the track that was recorded in double azimuth by helical scan is recorded in blocks for identification, so that the target track cannot be reproduced in a single trace. Can reconstruct data. With this non-tracking method, a margin of 4 times or more is allowed for track control within one track required by the conventional track servo.

  Further, the possibility of using non-tracking technology not only in helical scanning but also in linear recording has been studied (for example, Patent Documents 6 and 7).

  By the way, when a non-magnetic support having elasticity such as a polyester film is used for the magnetic recording medium substrate, even if double azimuth recording is performed, the allowable deformation amount is obtained by using a track servo. For example, when it is up to about twice the track width and further deformation occurs, the signal cannot be reproduced with a sufficient SN ratio. Also, in the case of recording without double azimuth, the width of the so-called guard band that does not cross the track is less than the amount of deformation of the tape so as not to deteriorate the reliability such as error rate even when the track servo is used. It was necessary to hold in

  Such a problem is caused by the fact that in the signal reproduction method that has been realized so far, the signal quality is significantly deteriorated when at least one reproduction head reads signals from a plurality of tracks simultaneously. In order to avoid this, it has been devised to perform guard band and double azimuth recording and to pick up only the signal from one track from the reproducing head.

However, when the track density is further increased, the installation of the guard band first hinders the installation. Also, the effect of double azimuth recording, which can reduce interference from adjacent tracks during reproduction, is reduced when the width is narrowed.

  This is the same even in the non-tracking method, and the reproducing head seems to reproduce the signal across a plurality of tracks. However, when time division is performed, the signal being reproduced always corresponds to one track. It wasn't going to play multiple tracks at the same time.

  Also, when trying to cope with higher track density with the non-tracking method, noise is mixed in by picking up signals from the adjacent track of the target track, so the limit to narrowing the track is the limit. It is coming.

  In addition to the background technology of the magnetic head device, a technique for recording a plurality of data frames at a time as a method of arranging a plurality of heads in one block and forming the same azimuth block in order to improve recording density. (For example, Patent Document 8 and Patent Document 9).

  Since these known techniques require that the reproducing head width be about half the width of the track, there is a restriction that the output of the reproducing signal cannot be made large, which is disadvantageous, for example, in securing the SN ratio. It was not necessarily suitable for higher density recording.

  A MIMO (Multi-Input / Multi-Output) technique is widely known as one used for wireless communication (for example, Patent Document 10).

  In addition, a technique using a technique related to MIMO for magnetic recording is also known (for example, Non-Patent Document 1). However, for example, when a reproducing head having a width wider than that of a recorded track is used, problems that occur in practical use have not been solved.

In the present invention, as a magnetic recording method using MIMO, it is impossible to foresee from the prior art to realize the practical application of the MIMO technology to the magnetic recording / reproducing method, which could not be realized by the paper introduced in the previous section. The technical contents will be clarified.
Japanese Patent No. 1842057 Japanese Patent No. 1842058 Japanese Patent No. 1842059 Japanese Patent Laid-Open No. 04-370580 Japanese Patent Laid-Open No. 05-020788 JP-A-10-283620 JP 2003-132504 A JP 2003-338812 A Japanese Patent Laid-Open No. 2004-071014 Japanese Patent No. 3664993 Paper IEEE Trans.Mag.Vol.30.No.6 Nov.1994 5100 pages

  As described above, in the conventional magnetic recording / reproducing system, a method of narrowing the track width on the magnetic recording medium has been adopted to increase the recording density. However, if the track width is narrowed in pursuit of a high recording density as it is, there arises a problem that the track cannot be tracked during reproduction. Therefore, a non-tracking method has been proposed in which a signal can be read from the track even if the position of the reproducing head is slightly deviated from the track. However, in order to obtain a reproduction signal appropriately by the non-tracking method, severe restrictions are imposed on the setting of the reproduction head. From this aspect, there is a limit to increasing the recording density by narrowing the track width.

  Therefore, the present inventors record a plurality of tracks, which are a unit of signal processing for reproducing data, on a magnetic recording medium by a recording head, and reproduce a signal across the plurality of tracks of the magnetic recording medium. The playback head can play back multiple signals for multiple tracks with different positional relationships with respect to multiple tracks, combine these playback signals into a single unit, and perform signal processing. A method of generating is proposed. According to this, the restriction for determining the width of the reproducing head is reduced, and the track width can be narrowed and the recording density can be increased.

  FIG. 23 is a diagram showing a configuration of a recording apparatus 800 that employs the above-described magnetic recording / reproducing method.

  As shown in the figure, the recording apparatus 800 includes a multitrack unit 110, a multitrack recording encoding unit 120, a multitrack preamble adding unit 130, a multitrack recording unit 140, and a recording head array 150.

  The multitrack unit 110 distributes the recording data 1 to the number of recording heads W-1, W-2, and W-3 (M = 3) provided in the recording head array 150 for multitracking. The data distributor 111 is used.

  The multitrack recording encoding unit 120 includes M recording encoding units 121-1, 121-2, and 121-3 that encode the recording data allocated to M by the data distributor 111.

  The multitrack preamble adding unit 130 adds M specific preambles 131-1, 131-2, 131- to each recording data encoded by the multitrack recording encoding unit 120 for each track. It is composed of three.

  The multi-track recording unit 140 is a means for recording the recording code string of each track to which the preamble is added on a recording medium. More specifically, the multi-track recording unit 140 provides M timings that give a desired timing to the recording code string to which the preamble is added. Output timing setting units 141-1, 141-2, 141-3, M recording compensation units 144-1, 144-2, 144-3 that perform recording compensation processing, and recording code strings after recording compensation processing Originally, it is composed of M recording amplifiers 147-1, 147-2, and 147-3 for driving the individual recording heads W-1, W-2, and W-3.

  FIG. 24 is a flowchart showing the unit recording operation by the recording apparatus 800. In this recording apparatus 100, first, the input recording data 1 is configured by the multitracking unit 110 as data (M = 3) of recording heads W-1, W-2, W-3, that is, a unit. The data is distributed to the data corresponding to the number of tracks to be processed (step S801).

  Each distributed data is encoded into a code string in consideration of recording / reproducing characteristics of the magnetic recording medium 2 by the recording encoding units 121-1, 121-2, and 121-3 of the multi-track recording encoding unit 120, respectively. Is done. At this time, information necessary for data demodulation, such as a demodulating synchronization pattern, is also added to the data code string (step S802).

  Next, control of reproducing unit-unit data by the preamble adding units 131-1, 131-2, and 131-3 of the multi-track preamble adding unit 130 at a predetermined position of each encoded recording data. Therefore, a necessary pattern is added as a preamble, and a recording code string is obtained (step S803).

  Here, the predetermined position of each encoded recording data is a position determined in consideration that recording code strings are continuously recorded and reproduced. The preamble includes, for example, a gain control pattern used for learning for gain control with respect to a reproduction signal, a synchronization pattern used for bit synchronization processing, and a plurality of reproduction heads and a plurality of tracks for one unit. There are separation patterns necessary to calculate a channel matrix corresponding to the positional relationship in the track width direction. Here, the plurality of tracks for one unit are a plurality of tracks constituting one unit of signal processing for reproducing data. The synchronization pattern is also used as information for specifying the separation pattern for each track and the start position of data. These patterns are created in consideration of the rules of the code strings generated by the recording encoding units 121-1, 121-2, and 121-3 of the multitrack recording encoding unit 120.

  The recording code string for each track is given a desired timing by the output timing setting units 141-1, 141-2, and 141-3 of the multitrack recording unit 140, and then the recording compensation units 144-1 and 144. At -2, 144-3, a recording compensation process for optimizing the recording on the magnetic recording medium 2 is performed.

  Thereafter, the recording code string for each track is converted from a voltage to a current by the recording amplifiers 147-1, 147-2, and 147-3 and sent to the recording heads W-1, W-2, and W-3 for recording. Recording is performed on the magnetic recording medium 2 by the heads W-1, W-2, and W-3 (step S804).

  The above unit-unit recording operation on the magnetic recording medium 2 is repeated so that a plurality of units are continuously arranged in the traveling direction of the track.

  Next, a reproducing apparatus employing the above magnetic recording / reproducing system will be described.

  FIG. 25 is a diagram showing the configuration of a reproducing apparatus 900 that employs the above-described magnetic recording / reproducing method.

  As shown in the figure, the reproducing apparatus 900 includes a reproducing head array 210, a channel reproducing unit 220, a signal separating unit 230, a multitrack demodulating unit 240, and a restoring unit 260.

  The reproducing head array 210 has N (N = 3) reproducing heads R-1, R-2, and R-3 that read signals from the tracks recorded on the magnetic recording medium 2. Each reproducing head R-1, R-2, R-3 has its head width and arrangement determined so that a signal can be reproduced from one or more adjacent tracks on the magnetic recording medium 2. Yes.

  The channel reproducing unit 220 amplifies signals reproduced by N reproducing heads R-1, R-2, and R-3 mounted on the reproducing head array 210, and N reproducing amplifiers 221-1 and 221-2. , 221-3 and N gain amplifiers 224-1, 224-2 for controlling the gain so that the amplitude levels of the outputs of the N reproduction amplifiers 221-1, 221-2, 221-3 become predetermined values. 224-3, and A / D converters 225-1, 225-2, and 225-3 that quantize the outputs of the gain adjusting units 224-1, 224-2, and 224-3 into digital values having a predetermined bit width. Prepare.

  Note that a low-pass filter that removes unnecessary high-frequency components may be provided immediately before the A / D converters 225-1, 225-2, and 225-3 as necessary.

  Further, the gain adjusting units 224-1, 224-2, and 224-3 may be arranged not in the preceding stage of the A / D converters 225-1, 225-2, and 225-3 but in the subsequent stage. This is because the bit widths of the A / D converters 225-1, 225-2, and 225-3 are used more effectively, and the configurations of the gain adjusting units 224-1, 244-2, and 224-3 are included in the preample. This is effective when it is desired to make it simple considering the detection of each pattern.

  The signal separation unit 230 includes a synchronization signal detector 231 that detects a synchronization pattern from the outputs of the A / D converters 225-1, 225-2, and 225-3, and a synchronization signal detected by the synchronization signal detector 231. Then, the start position of the separation pattern is specified, and the channel estimation calculation and the signal separation calculation are performed using the separation pattern, thereby being reproduced by the plurality of reproduction heads R-1, R-2, and R-3, respectively. And a signal separation processing unit 236 that separates the reproduction signal for each track from the reproduction signal for one unit.

  The multi-track demodulator 240 is configured with M equalizers 241-1, 241-2, 241-3 that perform equalization processing on the reproduction signal for each track separated by the signal separation processor 236, and the like. Generated by the M PLLs 242-1, 242-2, and 242-3 and the PLLs 242-1, 242-2, and 242-3 that perform bit synchronization from the outputs of the generators 241-1, 241-2, and 241-3. For example, M detectors 243-1, 243-2, and 243-3 such as a Viterbi detector, and a detector 243 are used to binarize the reproduction signal for each track using the bit synchronization signal. M synchronization signal detectors 244-1, 244-2, 244-3 for detecting a synchronization pattern on the code string from the binarized reproduction signals output from 1,243-2, 243-3, Synchronization signal detector 244-1 M decoders 245-1, 245-2, and 245-3 that identify the data start position based on the synchronization pattern detected by 44-2 and 244-3 and decode the data string from the code string; Is provided.

  The restoration unit 260 concatenates the data of each track output from the M decoders 245-1, 245-2, and 245-3 in the multitrack demodulation unit 240 by an operation reverse to that at the time of recording, and reproduces data. 3 is provided.

  FIG. 26 is a flowchart showing the flow of unit reproduction operation of the reproduction apparatus 900. In the reproducing apparatus 900, first, one unit of the magnetic recording medium 2 is formed by N reproducing heads R-1, R-2, and R-3 that can reproduce signals from one or more adjacent tracks. A signal is reproduced from a plurality of tracks (step S901).

  Next, after the gain adjustment units 224-1, 224-2, and 224-3 adjust the amplitude levels of the outputs of the reproduction amplifiers 221-1, 221-2, and 221-3, the gain adjustment unit 224- The outputs of 1, 244-2 and 224-3 are converted into digital values by A / D converters 225-1, 225-2, and 225-3 and output to the synchronization signal detector 231 (step S902).

  The synchronization signal detector 231 detects a synchronization pattern for knowing the start position of the separation pattern in the preamble for each output of the A / D converters 225-1, 225-2, and 225-3 (step S903). .

  Next, the signal separation processing unit 236 identifies the start position of the separation pattern based on the synchronization signal detected by the synchronization signal detector 231, and uses the separation pattern to perform each reproduction head R− by channel estimation calculation. After obtaining a channel matrix corresponding to the positional relationship in the track width direction between 1, R-2, R-3 and a plurality of tracks for one unit (step S904), each reproducing head R is used by using this channel matrix. The reproduction signal for each track is separated from the reproduction signal for one unit reproduced by -1, R-2, and R-3 (step S905).

  Thereafter, the multi-track demodulator 240 decodes the data sequence from the reproduction signal for each track (step S906), and the reconstruction unit 260 concatenates the data for each track to obtain reproduction data 3 (step S906). S907).

  By the way, as one of the technical problems for obtaining a more stable reproduction signal in the case of employing the above magnetic recording / reproduction method, there has been, for example, a stable signal separation process at the time of reproduction.

  That is, in the above magnetic recording / reproducing system, for example, during reproduction, it may be difficult to effectively obtain information necessary for channel estimation calculation with respect to the deviation of the reproducing head with respect to the track. In order to compensate for this, for example, it is necessary to separately detect the positional relationship such as which reproducing head straddles which track. At that time, it is necessary to consider perturbations such as a shift in the phase direction during recording and a shift in reproduction position during reproduction, which are not always easy.

  As a result, there is a possibility that the quality of the signal separation operation required for performing the signal separation operation due to a plurality of reproduction signals straddling tracks may deteriorate. If the quality of the signal separation operation is poor, the quality of the demodulation processing performed using the reproduction data for each track after separation may be lowered.

  In view of such circumstances, the present invention provides a track format capable of satisfactorily performing signal separation calculation processing and improving the quality of reproduced data even when there is a deviation of the reproducing head from the track. A recording medium, a recording apparatus, a recording method, a reproducing apparatus, a reproducing method, and a recording / reproducing apparatus are provided.

  In order to solve the above problems, the track format of the present invention is a track format that can be played back by a playback device having a playback head capable of playing back signals over a plurality of tracks, and for the data playback. Having a plurality of tracks that constitute a unit that is a unit of signal processing, and each of the plurality of tracks includes data and identification for individually identifying itself with respect to other tracks Information and a preamble including a separation pattern necessary for detecting the positional relationship in the track width direction during reproduction between the reproduction head and the plurality of tracks are arranged.

  According to the present invention, the position information of the separation pattern for each track can be obtained by detecting the identification information for each track at the time of data reproduction from this track format, and the information necessary for the channel estimation calculation is effectively obtained. Obtainable. Thereby, the quality of the signal separation process can be improved, and a high track density can be realized.

  In the track format of the present invention, the identification information may include information for identifying the unit. As a result, the track of the unit that is the target of data playback and the track of the adjacent unit can be identified during playback, and information necessary for channel estimation calculation can be obtained more effectively.

  In the track format of the present invention, the identification information may be arranged in the preamble as an identification pattern. Thereby, identification information can be reliably obtained by pattern detection from the reproduction signal obtained by the reproducing head during reproduction.

  In the track format of the present invention, it is preferable that the identification patterns of the tracks are arranged so as to be deviated from each other in the traveling direction of the tracks between adjacent tracks in the unit. Thereby, it is possible to avoid the interference of the identification pattern codes between adjacent tracks during reproduction, and it is possible to more effectively obtain information necessary for channel estimation calculation.

  In the track format of the present invention, the identification pattern of each track is arranged in the same range in the traveling direction of the track by setting the identification pattern of each track so as not to interfere between adjacent tracks in the unit. Recording density can be further increased.

  In the track format of the present invention, the preamble includes a gain control pattern for controlling gains of the plurality of reproduction signals reproduced by the reproduction head, and a synchronization pattern for synchronizing the plurality of reproduction signals. Further, it may be included. In this case, the identification information may be given by a combination of a plurality of types of synchronization patterns.

  A recording medium according to another aspect of the present invention is a recording medium capable of reproducing data by a reproducing apparatus having a reproducing head capable of reproducing a signal across a plurality of tracks, wherein the signal processing for the data reproduction is performed. A plurality of tracks constituting a unit which is a unit, and each of the plurality of tracks includes data, identification information for individually identifying itself with respect to other tracks, and A preamble including a separation pattern necessary for detecting a positional relationship in the track width direction during reproduction between the reproduction head and the plurality of tracks is recorded.

  According to the present invention, the position information of the separation pattern for each track can be obtained by detecting the identification information for each track at the time of data reproduction from this recording medium, and the information necessary for the channel estimation calculation is effectively obtained. Obtainable. Thereby, the quality of the signal separation process can be improved, and a high track density can be realized.

  A recording apparatus according to another aspect of the present invention is a recording apparatus for recording a plurality of tracks constituting a unit which is a unit of signal processing for data reproduction on a recording medium, and should be recorded for each track. A multi-track recording encoding unit that encodes data, and a code string of the data for each track encoded by the multi-track recording encoding unit, each of which is individually identified for other tracks To detect the positional relationship in the track width direction during reproduction between the reproduction head provided in the reproduction apparatus and capable of reproducing a signal across a plurality of tracks and the plurality of tracks. A multi-track preamble adding unit for adding a preamble including a necessary separation pattern, and the multi-track preamble adding unit. It is intended to and a multi-track recording unit that records data for each of the tracks amble is added to the recording medium by the recording head.

  By detecting the identification information for each track at the time of data reproduction from the recording medium recorded by the recording apparatus of the present invention, the position information of the separation pattern for each track can be obtained, which is necessary for the channel estimation calculation. Information can be obtained effectively. Thereby, the quality of the signal separation process can be improved, and a high track density can be realized.

  In the recording apparatus of the present invention, the identification information may include information for identifying the unit. Thereby, at the time of reproduction | regeneration, the track | truck of the unit which is the object of data reproduction | regeneration and the track | truck of an adjacent unit can be identified, and the information required for channel estimation calculation can be obtained more effectively.

  In the recording apparatus of the present invention, the preamble added by the multitrack preamble adding unit may include the identification information as an identification pattern. Thereby, at the time of reproduction | regeneration, identification information can be reliably obtained by pattern detection from the reproduction | regeneration signal obtained with the reproduction | regeneration head.

  In the recording apparatus of the present invention, the multi-track preamble adding unit is arranged so that the identification patterns of the tracks are shifted from each other in the traveling direction of the tracks between adjacent tracks in the unit. The preamble of each track may be added. Thereby, it is possible to avoid the interference of the identification pattern codes between adjacent tracks during reproduction, and it is possible to more effectively obtain information necessary for channel estimation calculation.

  In the recording apparatus of the present invention, the multi-track preamble adding unit may use a pattern that does not interfere between adjacent tracks in the unit as the identification pattern of each track. Thereby, the identification pattern of each track can be arranged in the same range in the traveling direction of the track, and the recording density can be further increased.

  In the recording apparatus of the present invention, the preamble added by the multitrack preamble adding unit includes a gain control pattern for controlling gains of the plurality of reproduction signals reproduced by the reproduction head, and the plurality of reproduction signals. It is also possible to further include a synchronization pattern for synchronizing the above. In this case, the identification information may be given by a combination of a plurality of types of synchronization patterns.

  A recording method according to another aspect of the present invention is a method for recording a plurality of tracks constituting a unit which is a unit of signal processing for data reproduction on a recording medium, and data to be recorded for each track. , Identification information for enabling each of the encoded code strings of the data for each of the encoded tracks to be individually identified with respect to other tracks, and the reproducing head And a step of adding a preamble including a separation pattern necessary for detecting a positional relationship in the track width direction at the time of reproduction with the plurality of tracks, and data for each track to which the preamble is added is recorded by the recording head. Recording on the recording medium.

  By detecting the identification information for each track during data reproduction from the recording medium recorded by the recording method of the present invention, the position information of the separation pattern for each track can be obtained, which is necessary for the channel estimation calculation. Information can be obtained effectively. Thereby, the quality of the signal separation process can be improved, and a high track density can be realized.

  A reproducing apparatus according to another aspect of the present invention includes a plurality of tracks that constitute a unit that is a unit of signal processing for reproducing the data, and each of the plurality of tracks includes data and another track. Information for enabling individual identification with respect to each other, and a positional relationship in a track width direction between the reproducing head capable of reproducing a signal across the plurality of tracks and the plurality of tracks An identification information detection unit that reproduces a recording medium on which a preamble including a separation pattern necessary for detecting a recording is recorded, and detects identification information for each track from a signal reproduced by the reproduction head And specifying the position of the separation pattern for each track in consideration of the identification information for each track detected by the identification information detector, and A channel estimation calculation unit that calculates a channel matrix corresponding to the positional relationship in the track width direction during reproduction between the reproduction head and the plurality of tracks based on the reproduction signal of the separation pattern for each of the tracks. .

  In the reproduction apparatus of the present invention, the reproduction signal of the data for each track is obtained from the reproduction signal of the data for one unit reproduced by the reproduction head using the channel matrix obtained by the channel estimation calculation unit. It is good also as providing the signal separation calculating part which isolate | separates.

  According to the present invention, by detecting the identification information for each track, the position information of the separation pattern for each track can be obtained, and the information necessary for the channel estimation calculation can be obtained effectively. Thereby, the quality of the signal separation process can be improved, and a high track density can be realized.

  A reproduction method according to another aspect of the present invention has a plurality of tracks constituting a unit which is a unit of signal processing for data reproduction, and each of the plurality of tracks includes data and another track. Identification information for enabling individual identification with respect to each other, and a positional relationship in a track width direction between the reproducing head capable of reproducing a signal across the plurality of tracks and the plurality of tracks. A method of reproducing a recording medium on which a preamble including a separation pattern necessary for detection is recorded, the step of detecting identification information for each track from a signal reproduced by the reproducing head, and the detection The position of the separation pattern for each track is specified in consideration of the identification information for each track, and the separation pattern for each unit is reproduced. Based on No., and a step of calculating a channel matrix corresponding to the position relationship between the track width direction at the time of reproduction of the plurality of tracks and the reproducing head.

  According to the present invention, by detecting the identification information for each track, the position information of the separation pattern for each track can be obtained, and the information necessary for the channel estimation calculation can be obtained effectively. Thereby, the quality of the signal separation process can be improved, and a high track density can be realized.

  A recording / reproducing apparatus according to another aspect of the present invention is a recording apparatus for recording a plurality of tracks constituting a unit which is a unit of signal processing for data reproduction on a recording medium, and recording is performed for each track. A multi-track recording encoding unit that encodes power data, and a code string of the data for each track encoded by the multi-track recording encoding unit, each of which is individually identified for other tracks The identification information for enabling this and the positional relationship in the track width direction during reproduction between the reproduction head provided in the reproduction apparatus and capable of reproducing signals across the plurality of tracks and the plurality of tracks are detected. A multi-track preamble adding unit for adding a preamble including a separation pattern necessary for the transmission, and the multi-track preamble adding unit. A recording device including a multi-track recording unit that records data for each track to which the preamble is added to the recording medium by a recording head; and a reproducing device that reproduces the recording medium recorded by the recording device. The identification information detection unit for detecting the identification information for each track from the signal reproduced by the reproduction head, and the identification information for each track detected by the identification information detection unit, The position of the separation pattern is specified, and a channel matrix corresponding to the positional relationship in the track width direction during reproduction between the reproduction head and the plurality of tracks is calculated based on the reproduction signal of the separation pattern for each unit. A channel estimation calculation unit.

  According to the present invention, even when there is a deviation of the reproducing head with respect to the track, the signal separation calculation process can be performed satisfactorily, and the quality of the reproduced data can be improved.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

  (First embodiment)

  As a first embodiment of the present invention, a recording apparatus and a reproducing apparatus in a magnetic recording / reproducing system using a multi-head will be described. The recording apparatus of this embodiment is an apparatus for recording signals on a tape-shaped magnetic recording medium without aligning the recording position for each track, and the reproducing apparatus does not align the reproducing position for each track from the magnetic recording medium. This is a device for reproducing a signal. Here, the number of recording heads is M, the number of reproducing heads is N, and in this embodiment, M = 3 and N = 3.

  FIG. 1 is a diagram showing a configuration of a recording apparatus 100 in the magnetic recording / reproducing system according to the first embodiment of the present invention.

  As shown in the figure, the recording apparatus 100 includes a multitrack unit 110, a multitrack recording encoding unit 120, a multitrack preamble adding unit 130, a multitrack recording unit 140, and a recording head array 150.

  The multitrack unit 110 distributes the recording data 1 to the number of recording heads W-1, W-2, and W-3 (M = 3) provided in the recording head array 150 for multitracking. The data distributor 111 is used.

  The multitrack recording encoding unit 120 includes M recording encoding units 121-1, 121-2, and 121-3 that encode the recording data allocated to M by the data distributor 111.

  The multitrack preamble adding unit 130 adds M preambles necessary for controlling data reproduction in units of units to each recording data encoded by the multitrack recording encoding unit 120. 1, 131-2, 131-3.

  The multi-track recording unit 140 is a means for recording the recording code string of each track to which the preamble is added on a recording medium. More specifically, the multi-track recording unit 140 provides M timings that give a desired timing to the recording code string to which the preamble is added. Output timing setting units 141-1, 141-2, 141-3, M recording compensation units 144-1, 144-2, 144-3 that perform recording compensation processing, and recording code strings after recording compensation processing Originally, it is composed of M recording amplifiers 147-1, 147-2, and 147-3 for driving the individual recording heads W-1, W-2, and W-3.

  The recording head array 150 has M recording heads W-1, W-2, and W-3 that are used to record tracks including data on the magnetic recording medium 2.

  FIG. 2 is a flowchart showing the unit recording operation by the recording apparatus 100. In this recording apparatus 100, first, the input recording data 1 is configured by the multitracking unit 110 as data (M = 3) of recording heads W-1, W-2, W-3, that is, a unit. The data is distributed to the data corresponding to the number of tracks to be performed (step S101).

  Each distributed data is encoded into a code string in consideration of recording / reproducing characteristics of the magnetic recording medium 2 by the recording encoding units 121-1, 121-2, and 121-3 of the multi-track recording encoding unit 120, respectively. Is done. At this time, information necessary for data demodulation such as a synchronization pattern for demodulation is also added to the data code string (step S102).

  Next, the respective recordings encoded by the recording encoding units 121-1, 121-2, 121-3 by the independent preamble adding units 131-1, 131-2, 131-3 of the multitrack preamble adding unit 130. A preamble necessary for data reproduction control is added to the data, and a recording code string is obtained (step S103).

  Here, as a preamble pattern necessary for control of reproducing data, for example, a gain control pattern used for learning for gain control on a reproduction signal, synchronization used for synchronization detection for bit synchronization processing, etc. There are a pattern, an identification pattern for identifying a track, and a separation pattern necessary for calculating a channel matrix corresponding to the positional relationship in the track width direction between a plurality of reproducing heads and a plurality of tracks for one unit. . The plurality of tracks for one unit are a plurality of tracks constituting a unit that is one unit of signal processing for data reproduction. The synchronization pattern is also used as information for specifying the separation pattern for each track and the head position of data. These patterns are created in consideration of the rules of the code strings generated by the recording encoding units 121-1, 121-2, and 121-3 of the multitrack recording encoding unit 120.

  The recording code string for each track is given a desired timing by the output timing setting units 141-1, 141-2, and 141-3 of the multitrack recording unit 140, and then the recording compensation units 144-1 and 144- At 2, 144-3, a recording compensation process for optimizing the recording on the magnetic recording medium 2 is performed. The recording code string for each track on which the recording compensation processing has been performed is converted from voltage to current by recording amplifiers 147-1, 147-2, and 147-3, and is then applied to recording heads W-1, W-2, and W-3. Then, it is recorded on the magnetic recording medium 2 by the recording heads W-1, W-2, W-3 (step S104).

  Next, a reproducing apparatus in the magnetic recording / reproducing system according to the first embodiment of the present invention will be described.

  FIG. 3 is a diagram showing the configuration of the reproducing apparatus 200 in the magnetic recording / reproducing system of the first embodiment.

  As shown in the figure, the playback apparatus 200 includes a playback head array 210, a channel playback unit 220, a signal separation processing unit 230, a multitrack demodulation unit 240, and a restoration unit 260.

  The reproducing head array 210 has N (N = 3) reproducing heads R-1, R-2, and R-3 that read signals from the tracks recorded on the magnetic recording medium 2. Each reproducing head R-1, R-2, R-3 has its head width and arrangement determined so that a signal can be reproduced from one or more adjacent tracks on the magnetic recording medium 2. Yes.

  The channel reproducing unit 220 amplifies signals reproduced by N reproducing heads R-1, R-2, and R-3 mounted on the reproducing head array 210, and N reproducing amplifiers 221-1 and 221-2. , 221-3 and N gain amplifiers 224-1, 224-2 for controlling the gain so that the amplitude levels of the outputs of the N reproduction amplifiers 221-1, 221-2, 221-3 become predetermined values. 224-3, and A / D converters 225-1, 225-2, and 225-3 that quantize the outputs of the gain adjusting units 224-1, 224-2, and 224-3 into digital values having a predetermined bit width. Prepare.

  Note that a low-pass filter that removes unnecessary high-frequency components may be provided immediately before the A / D converters 225-1, 225-2, and 225-3 as necessary.

  Further, the gain adjusting units 224-1, 224-2, and 224-3 may be arranged not in the preceding stage of the A / D converters 225-1, 225-2, and 225-3 but in the subsequent stage. This is because the bit widths of the A / D converters 225-1, 225-2, and 225-3 are used more effectively, and the configurations of the gain adjusting units 224-1, 244-2, and 224-3 are included in the preample. This is effective when it is desired to make it simple considering the detection of each pattern.

  The signal separation processing unit 230 includes a synchronization signal detection unit 231, an identification information detection unit 232, a reproduction signal gain control processing unit 233, a channel estimation calculation unit 234, a reproduction position control processing unit 235, and a signal separation calculation unit 236. Yes.

  The synchronization signal detection unit 231 calculates the synchronization pattern in the preamble from the reproduction signals for the reproduction heads R-1, R-2, and R-3 output from the A / D converters 225-1, 225-2, and 225-3. To detect.

  The identification information detection unit 232 identifies the position of the identification pattern in the reproduction signal of each reproduction head R-1, R-2, R-3 based on the synchronization pattern detected by the synchronization signal detection unit 231, This identification pattern is detected to obtain track identification information.

  The reproduction signal gain control processing unit 233 detects the gain control pattern in the preamble from the reproduction signals of the reproduction heads R-1, R-2, R-3 that have passed through the synchronization signal detection unit 231, and this gain control pattern. Based on this signal, the gain for each reproduction head R-1, R-2, R-3 is calculated, and the level of the reproduction signal from each reproduction head R-1, R-2, R-3 is calculated. To control.

  The channel estimation calculation unit 234 specifies the head position of the separation pattern based on the synchronization pattern detected by the synchronization signal detector 231 and the identification information obtained by the identification information detection unit 232, and uses this separation pattern. Thus, channel estimation calculation is performed to calculate a channel matrix corresponding to the positional relationship in the track width direction during reproduction between the reproducing heads R-1, R-2, R-3 and a plurality of tracks.

  The reproduction position control processing unit 235 reproduces the reproduction heads R-1, R-2, and R-3 that have passed through the reproduction signal gain control processing unit 233 based on the synchronization pattern detected by the synchronization signal detection unit 231. Performs processing to match the playback position of the signal.

  The signal separation calculation unit 236 is a channel matrix obtained by the channel estimation calculation unit 234 from the reproduction signals of the reproduction heads R-1, R-2, and R-3 whose reproduction positions are aligned by the reproduction position control processing unit 235. Is used to perform a process of separating the reproduction signal for each track by a predetermined calculation process.

  The signal separation processing unit 230 has a storage unit (not shown) that stores information necessary for processing. The signal separation processing unit 230 performs processing by storing information for a predetermined unit including a preamble and data, for example, in the storage unit.

  As shown in FIG. 4, the multi-track demodulation unit 240 performs M equalizers 241-1 and 241-2 that perform equalization processing on the reproduction signal for each track separated by the signal separation operation unit 236. , 241-3, M PLLs 242-1, 242-2, and 242-3 that perform bit synchronization from the outputs of the equalizers 241-1, 241-2, and 241-3, and PLLs 242-1 and 242-2 , 242-3 is used to generate a code string by binarizing the reproduction signal of each track using the bit synchronization signal generated by M, 24-3, 243-2, 243, for example, a Viterbi detector. 3 and M synchronization signal detectors 244-1, 244- for detecting a synchronization pattern on the code string from the binarized reproduction signals output from the detectors 243-1, 243-2, 243-3. 2,244-3 and sync signal detection M decoders 245-1 and 245-2 that specify the head position of the data based on the synchronization patterns detected by the units 244-1, 244-2 and 244-3 and decode the data sequence from the code sequence. , 245-3. Note that the multitrack demodulation unit 240 has a storage unit (not shown) that stores information such as data necessary for performing the above processing.

  Returning to FIG. 3, the restoration unit 260 operates the data of each track output from the M decoders 245-1, 245-2, and 245-3 in the multi-track demodulation unit 240 in the reverse operation to the recording time. And a data combiner 261 for recovering the reproduction data 3 by connecting them.

  FIG. 5 is a flowchart showing a unit reproduction operation flow of the reproduction apparatus 200.

  In the reproducing apparatus 200, first, one unit of the magnetic recording medium 2 is formed by N reproducing heads R-1, R-2, and R-3 that can reproduce signals from one or more adjacent tracks. A signal is reproduced from a plurality of tracks (step S201).

  Next, after the gain adjustment units 224-1, 224-2, and 224-3 adjust the amplitude levels of the outputs of the reproduction amplifiers 221-1, 221-2, and 221-3, the gain adjustment unit 224- The outputs of 1, 244-2 and 224-3 are converted into digital values by the A / D converters 225-1, 225-2 and 225-3 and output to the synchronization signal detector 231 (step S202).

  Next, the synchronization signal detector 231 synchronizes from the reproduction signals output from the A / D converters 225-1, 225-2, and 225-3 for the respective reproduction heads R-1, R-2, and R-3. Each pattern is detected (step S203).

  Next, based on the synchronization pattern detected by the synchronization signal detection unit 231 by the identification information detection unit 232, the head position of the identification pattern in the reproduction signal of each reproduction head R-1, R-2, R-3 Is identified and an identification pattern is detected to obtain identification information (step S204).

  Subsequently, the reproduction signal gain control processing unit 233 detects the gain control pattern in the preamble from the reproduction signals of the reproduction heads R-1, R-2, and R-3 that have passed through the synchronization signal detector 231. Based on the gain control pattern, the gain for the reproduction signal of each reproduction head R-1, R-2, R-3 is calculated, and the reproduction signal of each reproduction head R-1, R-2, R-3 is calculated. The level is individually controlled (step S205).

  Next, based on the synchronization pattern detected by the synchronization signal detector 231 and the identification information detected by the identification information detection unit 232 in the channel estimation calculation unit 234, each reproducing head R-1, R-2 is recorded. , R-3, the head position of the separation pattern included in the reproduction signal is specified, and a channel matrix is obtained by a predetermined channel estimation calculation using these separation patterns (step S206).

  Next, in the reproduction position control processing unit 235, each reproduction head R-1, R-2, R that has passed through the reproduction signal gain control processing unit 233 based on the synchronization pattern detected by the synchronization signal detection unit 231. -3 is performed to match the reproduction position of the reproduction signal (step S207).

  Next, in the signal separation calculation unit 236, the channel estimation calculation unit 234 obtains the reproduction signals of the reproduction heads R-1, R-2, and R-3 whose reproduction positions are aligned by the reproduction position control processing unit 235. Using the channel matrix thus obtained, a process for separating the reproduction signal for each track is performed (step S208).

  Thereafter, the multi-track demodulator 240 decodes the data sequence from the reproduction signal for each track (step S209), and the restoration unit 260 concatenates the data of each track to obtain reproduction data 3 (step S209). S210).

  FIG. 6 is a conceptual diagram of a track format on the magnetic recording medium 2 on which recording has been performed by the recording apparatus 100 described above.

  Track # 1, track # 2, and track # 3 are tracks recorded on the magnetic recording medium 2 by M (M = 3) recording heads of the recording apparatus 100, respectively. Preamble 21 and data 22 are recorded on track # 1, track # 2, and track # 3, respectively. As described above, the preamble 21 identifies, as information necessary for reproducing the data 22, a gain control pattern used for learning for gain control on a reproduction signal, a synchronization pattern used for bit synchronization processing, and a track. And a separation pattern necessary for calculating a channel matrix corresponding to the positional relationship in the track width direction between a plurality of reproducing heads and a plurality of tracks for one unit.

  Here, a unit 51 as a unit of signal processing for reproducing data is a group of M preambles 21 and M data 22 in each of M tracks # 1, # 2, and # 3. It is.

  In the magnetic recording medium 2, S units 51 are arranged in parallel to each other, and between the adjacent units 51, an area where nothing is recorded, which is called a guard band 52, is provided. The purpose of the guard band 52 is to prevent the track of the adjacent unit 51 from being reproduced.

  FIG. 7 is a diagram showing the configuration of the preamble 21 in the track format of FIG.

  The first preamble 23 includes gain control patterns 41-1, 41-2, 41-3, synchronization patterns 42-1, 42-2, 42-3 and identification patterns 43-1, 43-2, 43-3. The gain control patterns 41-1, 41-2, and 41-3, the synchronization patterns 42-1, 42-2, and 42-3, and the identification patterns 43-1, 43-2, and 43-3 are continuously arranged. Has been. The second preamble 24 is composed of separation patterns 44-1, 44-2, 44-3. On the track # 1, the gain control pattern 41-1, the synchronization pattern 42-1, the identification pattern 43-1, and the separation pattern 44-1 are arranged in this order from the top. On the track # 2, the gain control pattern 41- 2, the synchronization pattern 42-2, the identification pattern 43-2, and the separation pattern 44-2 are arranged in this order. On the track # 3, the gain control pattern 41-3, the synchronization pattern 42-3, and the identification pattern 43-3 are arranged from the head. The separation patterns 44-3 are arranged in this order. Data 22 is arranged after the separation patterns 44-1, 44-2, and 44-3. Data 22 is a recording code string created by the recording encoding units 121-1, 121-2, and 121-3 of the recording apparatus 100 of FIG. The first preamble 23 and the second preamble 24 are added to the recording code string by the independent preamble adding units 131-1, 131-2, and 131-3.

  In the example of FIG. 7, the widths of the reproducing heads R-1, R-2, and R-3 are 1.5 times the track width. That is, the width of the reproducing heads R-1, R-2, and R-3 is 1.5 times the head width of the recording heads W-1, W-2, and W-3, and the individual reproducing heads R-1 , R-2, and R-3 can reproduce signals from a plurality of tracks. That is, the reproducing head R-1 reproduces a signal over the tracks # 1 and # 2, and the reproducing head R-2 reproduces a signal over the three tracks # 1, # 2, and # 3. The reproducing head R-3 reproduces the signal across the track # 2 and the track # 3.

  In the first preamble 23, gain control patterns 41-1, 41-2, 41-3, synchronization patterns 42-1, 42-2, 42-3 and identification patterns 43 of the respective tracks # 1, # 2, # 3 are recorded. −1, 43-2, and 43-3 are arranged so that the positions in the traveling direction of the tracks do not overlap each other. That is, in FIG. 7, the gain control pattern 41-1 of the track # 1, the synchronization pattern 42-1 and the identification pattern 43-1 are the gain control pattern 41-2, the synchronization pattern 42-2 of the track # 2 and the The identification pattern 43-2 is arranged in the T2 section, and the gain control pattern 41-3, the synchronization pattern 42-3, and the identification pattern 43-3 of the track # 3 are arranged in the T3 section. And each of the gain control patterns 41-1, 41-2, 41-3, the synchronization patterns 42-1, 42-2, 42-3, and the identification patterns 43-1, 43-2, 43-3 of the adjacent tracks. A gap 28 for a margin is provided between the recording sections.

  At the time of reproduction, the gain control patterns 41-1, 41-2 and 41-3 of the tracks # 1, # 2 and # 3 are, for example, gain adjustment units 224-1 in the reproduction apparatus 200 shown in FIG. It is used as a learning signal for gain control of the reproduction amplifiers 221-1, 221-2, and 221-3 by 224-2 and 224-3. The gain control patterns 41-1, 41-2, and 41-3 are used for learning for bit synchronization detection by the synchronization signal detector 231 and for each reproduction by the reproduction signal gain control processing unit 233 as necessary. It is also used for signal level control. Furthermore, the gain control patterns 41-1, 41-2, and 41-3 are used for reproduction position control of each reproduction signal in the reproduction position control processing unit 235 as necessary.

  At the time of reproduction, the synchronization patterns 42-1, 42-2, and 42-3 of the tracks # 1, # 2, and # 3 are detected by the synchronization signal detector 231. For example, the tracks # 1, # 2 , # 3 identification patterns 43-1, 43-2, 43-3, the leading positions of the separation patterns 44-1, 44-2, 44-3 of the tracks # 1, # 2, and # 3 and the head of the data 22 Used as information for knowing the position. The synchronization patterns 42-1, 42-2, and 42-3 are used for playback position control of each playback signal in the playback position control processing unit 235.

  Also, at the time of reproduction, the identification patterns 43-1, 43-2 and 43-3 of the tracks # 1, # 2 and # 3 are detected by the identification information detection unit 232 and used to obtain track identification information. In addition, it is used for channel estimation calculation in the channel estimation calculation unit 234. Further, the identification information is used for playback position control in the playback position control processing unit 235.

  In this track format, in the first preamble 23, the gain control patterns 41-1, 41-2, 41-3 and the synchronization patterns 42-1, 42-2, 42- of the tracks # 1, # 2, and # 3 are provided. 3 and the identification patterns 43-1, 43-2, 43-3 are arranged so that their positions in the direction in which the tracks travel do not overlap each other, so that each track # 1, # 2, # 3 Even when the channel clock positions of the recording heads do not match, when each of the reproducing heads R-1, R-2, R-3 reproduces a signal across a plurality of tracks, the reproduced signal by cancellation of the recording signals of each track No decrease in output occurs. As a result, the gain control patterns 41-1, 41-2, 41-3, the synchronization patterns 42-1, 42-2, 42-3, and the identification patterns 43-1, 43-2, 43-3 above are used. Control can be performed satisfactorily.

  On the other hand, in the second preamble 24, the separation patterns 44-1, 44-2, and 44-3 of the tracks # 1, # 2, and # 3 are reproduced at the reproduction head R-1 by the channel estimation calculation unit 234 during reproduction. , R-2, R-3 are used for obtaining a channel matrix necessary for calculation for separating the reproduction signals for tracks # 1, # 2, and # 3 from the reproduction signals for each of the tracks # 1, # 2, and # 3. Pattern.

  These separation patterns 44-1, 44-2, and 44-3 are also arranged so that the positions in the traveling direction of the tracks do not overlap each other. That is, in FIG. 7, the separation pattern 44-1 for track # 1 is recorded in the T4 section, the separation pattern 44-2 for track # 2 is recorded in the T5 section, and the separation pattern 44-3 for track # 3 is recorded in the T6 section. ing. As a result, there are three types of separation patterns corresponding to the number of tracks. A gap 29 for a predetermined time is provided for a margin between the recording sections of the separation patterns 44-1, 44-2, and 44-3 of adjacent tracks.

  Here, the separation patterns 44-1, 44-2, and 44-3 are recorded at a predetermined recording wavelength equal to or greater than the minimum recording wavelength.

  During reproduction, the channel estimation calculation unit 234 performs channel estimation calculation using the reproduction signals of the separation patterns 44-1, 44-2, 44-3, and generates a channel matrix as a result. This channel matrix corresponds to position information in the track width direction of the individual reproducing heads R-1, R-2, and R-3 for the tracks # 1, # 2, and # 3 in one unit, in other words. Information indicating which track in the unit overlaps with which track in each unit, each reproducing head R-1, R-2, R-3.

  Next, returning to FIG. 6, the details of the identification patterns 43-1, 43-2, 43-3 arranged in the first preamble 23 of each track # 1, # 2, # 3 will be described.

  As shown in FIG. 6, the identification information encoded as the identification pattern includes, for example, a number that identifies the unit, for example, a number from “1” to “s” and a track that identifies the track in the unit, for example, “1” to “6”. "Represented by a combination of numbers up to. For example, “1_2” indicates the second track of the first unit.

  When the maximum number of units is 8192 and the maximum number of tracks in the unit is 8, the number of bits expressing the identification information is at least 13 bits for the number identifying the unit, and for the number identifying the track. Therefore, at least 3 bits may be allocated, for a total of 16 bits.

  Further, as described above, instead of giving an identification number to the unit, the unit may be identified by, for example, a system frame unit or an error correction format unit.

  Next, details of processing performed in main blocks in the playback apparatus 200 of FIG. 3 will be described.

  (About the identification information detection unit 232)

  The identification information detection unit 232 reproduces each reproduction head R-1, R-2, R-3 based on the synchronization patterns 42-1, 42-2, 42-3 detected by the synchronization signal detection unit 231. The head positions of the identification patterns 43-1, 43-2, 43-3 in the signal are specified, the identification patterns 43-1, 43-2, 43-3 are detected, and the track identification information is output.

  When one reproduction head straddles a plurality of tracks, the synchronization signal detection unit 231 detects the synchronization pattern of each track in a different section from the reproduction signal obtained by the reproduction head. The identification information detection unit 232 specifies the head position of the identification pattern of each track using each synchronization pattern, detects each identification pattern, and obtains identification information of each track.

  (Reproduction signal gain control processing unit 233)

  The reproduction signal gain control processing unit 233 uses, for example, the following reproduction signals from the gain control patterns 41-1, 41-2, and 41-3 for the reproduction heads R-1, R-2, and R-3. In this way, the gain of the reproduction signal for each of the reproduction heads R-1, R-2, R-3 is calculated, and the level of each reproduction signal is controlled.

  For example, the reproduction signal gain control processing unit 233 adds the signals of the gain control pattern 41-1 and the gain control pattern 41-2 respectively reproduced from the track # 1 and the track # 2 by the reproduction head R-1 in FIG. To do. Similarly, the reproduction signal gain control processing unit 233 controls the gain control pattern 41-1 and the gain control pattern 41-2 reproduced from the track # 1, the track # 2, and the track # 3 by the reproduction head R-2. The signals of the pattern 41-3 are added. Similarly, the reproduction signal gain control processing unit 233 adds the signals of the gain control pattern 41-2 and the gain control pattern 41-3 reproduced from the track # 2 and the track # 3 by the reproduction head R-3.

  The addition of the reproduction signal of the gain control pattern is performed, for example, by detecting the peak value of the reproduction signal of the gain control pattern in each track and obtaining the average value thereof. Note that this calculation is not limited to the above method, and another method may be used as long as the correlation between the reproduced signals is established.

  The reproduction signal gain control processing unit 233 selects the maximum one of the three calculation results obtained as described above, and uses this as a reference output for all the reproduction heads R-1, R-2, R-3. And The reproduction signal gain control processing unit 233 outputs, as a control result, a value obtained by multiplying the input reproduction signal value for each reproduction head by 1 / (reference output).

  The reference output can also be used in channel estimation calculation in the channel estimation calculation unit 234 and can also be used in the signal separation calculation unit 236.

  (About channel estimation calculation unit 234)

  Based on the synchronization pattern detected by the synchronization signal detection unit 231 and the track identification information detected by the identification information detection unit 232, the channel estimation calculation unit 234 separates the separation patterns 44-1, 44-2, 44-3. , The channel estimation calculation is performed based on the reproduction signals of these separation patterns 44-1, 44-2, 44-3, and the reproduction signal gain control processing unit 233 controls the level. A channel matrix necessary for separating the reproduction signal for each track from the reproduction signal for one unit is generated. At this time, based on the identification information of each track detected by the identification information detection unit 232, the channel estimation calculation unit 234 determines that the heads of the separation patterns 44-1, 44-2, 44-3 of the respective tracks are Since it is possible to know how far the corresponding track synchronization patterns 42-1, 42-2, 42-3 are from the detected position, the separation patterns 44-1, 44-2, 44-3 The reproduced signal can be discriminated with high accuracy, and the channel estimation calculation can be performed with high accuracy.

  Here, as a comparative example with the present invention, a method for determining the head position of the separation pattern of each track using only the synchronization pattern and the problems in this case will be described.

  FIG. 8 is a diagram showing the configuration of the preamble 21 in the track format in the comparative example. As shown in the figure, the preamble 21 includes a first preamble 23 and a second preamble 24. The first preamble 23 is composed of gain control patterns 41-1, 41-2, 41-3 and synchronization patterns 42-1, 42-2, 42-3, and the gain control patterns 41-1, 41-2. , 41-3 and the synchronization patterns 42-1, 42-2, 42-3 are continuously arranged. The second preamble 24 is composed of separation patterns 44-1, 44-2, 44-3. On the track # 1, the gain control pattern 41-1, the synchronization pattern 42-1, and the separation pattern 44-1 are arranged in this order from the top. On the track # 2, the gain control pattern 41-2 and the synchronization pattern 42- are arranged from the top. 2, the separation pattern 44-2 is arranged in this order, and on the track # 3, the gain control pattern 41-3, the synchronization pattern 42-3, and the separation pattern 44-3 are arranged in this order from the top. Data 22 is arranged after the separation patterns 44-1, 44-2, 44-3.

  In the first preamble 23, the gain control patterns 41-1, 41-2, 41-3 and the synchronization patterns 42-1, 42-2, 42-3 of the tracks # 1, # 2, # 3 are respectively They are arranged so that their positions do not overlap each other. That is, in FIG. 8, the gain control pattern 41-1 and the synchronization pattern 42-1 of the track # 1 are in the T1 section, and the gain control pattern 41-2 and the synchronization pattern 42-2 of the track # 2 are in the T2 section. 3 gain control pattern 41-3 and synchronization pattern 42-3 are arranged in the T3 section. A gap 28 for a margin is provided between the recording sections of the gain control patterns 41-1, 41-2, 41-3 and the synchronization patterns 42-1, 42-2, 42-3 of adjacent tracks. Yes.

  On the other hand, the second preambles 24 are also arranged such that their positions do not overlap each other. That is, in FIG. 8, the separation pattern 44-1 for track # 1 is recorded in the T4 section, the separation pattern 44-2 for track # 2 is recorded in the T5 section, and the separation pattern 44-3 for track # 3 is recorded in the T6 section. ing. A gap 29 for a predetermined time is provided for a margin between the recording sections of the separation patterns 44-1, 44-2, and 44-3 of adjacent tracks.

  In short, the track format preamble 21 of this comparative example is obtained by removing the identification patterns 43-1, 43-2, and 43-3 from the track format preamble 21 of the present embodiment shown in FIG.

  Also in this comparative example, as in the present embodiment, the widths of the reproducing heads R-1, R-2, R-3 are 1.5 times the track width, and the individual reproducing heads R-1, R- 2 and R-3 can reproduce signals from a plurality of tracks. That is, the reproducing head R-1 reproduces a signal over the tracks # 1 and # 2, and the reproducing head R-2 reproduces a signal over the three tracks # 1, # 2, and # 3. The reproducing head R-3 reproduces a signal across the track # 2 and the track # 3.

  FIG. 9 shows each of the cases where there is no off-track, that is, when the centers of the reproducing heads R-1, R-2, and R-3 coincide with the centers of the tracks # 1, # 2, and # 3, respectively. FIG. 4 is a diagram showing reproduction signals of reproduction heads R-1, R-2, and R-3. In FIG. 9, the size of the reproduction signal in the track width direction corresponds to the output size. For the sake of simplicity, it is assumed that there is no phase shift during recording and reproduction.

  In this case, reproduction signals 61 and 68 for track # 1 and small reproduction signals 62 and 70 for track # 2 are obtained by reproduction head R-1.

  By the reproducing head R-2, small reproduction signals 63 and 69 for track # 1, reproduction signals 64 and 71 for track # 2, and small reproduction signals 65 and 73 for track # 3 are obtained.

  The reproduction head R-3 provides small reproduction signals 66 and 72 for track # 2 and reproduction signals 67 and 74 for track # 3.

  10 shows the reproduction signals of the reproducing heads R-1, R-2, R-3 when the positions of the reproducing heads R-1, R-2, R-3 are shifted upward with respect to FIG. It is the figure which showed the example.

  In this case, only the reproduction signals 61 and 68 of the track # 1 are obtained by the reproduction head R-1. The reproduction head R-2 provides slightly smaller reproduction signals 63 and 69 for the track # 1 and reproduction signals 64 and 71 for the track # 2. The reproduction head R-3 provides slightly smaller reproduction signals 66 and 72 for track # 2 and reproduction signals 67 and 74 for track # 3.

  FIG. 11 shows the reproduction signals of the reproducing heads R-1, R-2, R-3 when the positions of the reproducing heads R-1, R-2, R-3 are shifted downward with respect to FIG. It is the figure which showed the example.

  In this case, reproduction signals 61 and 68 for track # 1 and slightly smaller reproduction signals 62 and 70 for track # 2 are obtained by reproduction head R-1. The reproduction head R-2 provides reproduction signals 64 and 71 for track # 2 and slightly smaller reproduction signals 65 and 73 for track # 3. Only the reproduction signals 67 and 74 of the track # 3 are obtained by the reproducing head R-3.

  In the example of FIGS. 9 to 11, the length of the first preamble for each track is 30 data, the length of the gap between the first preambles of adjacent tracks is 10 data, and the separation pattern for each track is It is assumed that 60 data is assigned as the length, and 10 data is assigned as the length of the gap between the first preamble of track # 3 and the separation pattern of track # 1.

  Here, in the reproduction signal # 2 of the reproduction head R-2, the synchronization patterns 42-1, 42-2, and 42-3 in the first preamble and the separation patterns 44-1 and 44-2 that are the second preambles. , 44-3.

  As shown in FIG. 9, when there is no off-track, the first and second preambles of all tracks # 1, # 2, and # 3 are reproduced by the reproducing head R-2. At this time, the synchronization pattern to be reproduced first is the synchronization pattern 42-1 of the track # 1, and the position behind the position end position of the synchronization pattern 42-1 by 90 (10 + 30 + 10 + 30 + 10) data is the separation pattern of the track # 1. 44-1.

  As shown in FIG. 10, when there is an upward off-track, the reproduction head R-2 reproduces the first preamble and the second preamble of the track # 1 and the track # 2. At this time as well, since the synchronization pattern to be reproduced first is the synchronization pattern 42-1 of the track # 1, the position behind the position end position of the synchronization pattern 42-1 by 90 (10 + 30 + 10 + 30 + 10) data is the separation pattern of the track # 1. 44-1.

  As shown in FIG. 11, when there is a downward off-track, the reproduction head R-2 reproduces the first preamble and the second preamble of the track # 2 and the track # 3. At this time, the synchronization pattern to be reproduced first is the synchronization pattern 42-2 of the track # 2, and the position behind the detection end position of the synchronization pattern 42-2 by 50 data (10 + 30 + 10) is the separation pattern of the track # 1. 44-1.

  That is, in this comparative example, when there is no off-track and when there is an upward off-track and when there is a downward off-track, the track is detected from the detection end position of the synchronization pattern detected first. Since a difference occurs in the interval to the head position of the separation pattern 44-1 of # 1, it becomes difficult to effectively obtain information necessary for channel estimation calculation.

  Even when there is no off-track, since the first synchronization pattern is detected from the reproduction signal 63 of the track # 1 with a small output, the detection becomes unstable with respect to disturbances such as noise during recording and reproduction. It is expected that. In this respect as well, it is difficult to effectively obtain information necessary for channel estimation calculation. As a result, the quality of the signal separation operation is lowered, and the quality of the demodulation processing performed using the reproduction data for each track after separation may be lowered.

  Therefore, in this embodiment, based on the identification information of each track, the heads of the separation patterns 44-1, 44-2, 44-3 of the respective tracks are the synchronization patterns 42-1, 42- of the corresponding tracks. It is calculated | required as follows how much it exists from the position where 2,42-3 was detected.

  Here, in the reproduction signal # 2 of the reproduction head R-2, the synchronization patterns 42-1, 42-2, and 42-3 in the first preamble and the separation patterns 44-1 and 44-2 that are the second preambles. , 44-3.

  As shown in FIG. 9, when there is no off-track, the first and second preambles of all tracks # 1, # 2, and # 3 are reproduced by the reproducing head R-2. At this time, the identification information detection unit 232 first detects the identification pattern 43-1 included in the reproduction signal 63 of the track # 1 in the reproduction signal # 2 of the reproduction head R-2. Here, it is assumed that “1_1” indicating the first track # 1 of the first unit is obtained as the identification information of the track # 1, for example. In this case, the separation pattern 44 of the track # 1 is a position after the detection end position of the identification pattern 43-1 of the track # 1 by a predetermined amount of data with respect to the track # 1, ie, 90 (10 + 30 + 10 + 30 + 10) data. The information indicating that the position is the head position of -1 is obtained.

  Next, the identification information detection unit 232 detects the identification pattern 43-2 included in the reproduction signal 64 of the track # 2 in the reproduction signal # 2 of the reproduction head R-2. Here, for example, it is assumed that “1_2” indicating the second track # 2 of the first unit is obtained as the identification information of the track # 2. In this case, the separation pattern 44 of the track # 2 is a position after the detection end position of the identification pattern 43-2 of the track # 2 by a predetermined amount of data with respect to the track # 2, ie, 120 (10 + 30 + 10 + 60 + 10) data. -2 so that it is possible to obtain information that it is the head position.

  Next, the identification information detection unit 232 detects the identification pattern 43-3 included in the reproduction signal 65 of the track # 3 in the reproduction signal # 2 of the reproduction head R-2. Here, it is assumed that “1_3” indicating the third track # 3 of the first unit is obtained as the identification information of the track # 3, for example. In this case, the separation pattern 44 of the track # 3 is a position that is behind the detection end position of the identification pattern 43-3 of the track # 3 by a predetermined amount of data with respect to the track # 3, that is, 150 (10 + 60 + 10 + 60 + 10) data. -3 so that it can be obtained information that it is the head position.

  As described above, the identification patterns 43-1, 43-2 and 43-3 are detected for each of the tracks # 1, # 2 and # 3 to obtain the identification information, thereby obtaining the identification patterns 43-1, 43-2 and 43. The information indicating how far the separation pattern 44-1, 44-2, 44-3 is located behind the detection end position of −3 can be obtained.

  As shown in FIG. 10, when there is an upward off-track, the reproduction head R-2 reproduces the first preamble and the second preamble of the track # 1 and the track # 2. At this time, the identification information detection unit 232 first detects the identification pattern 43-1 included in the reproduction signal 63 of the track # 1 in the reproduction signal # 2 of the reproduction head R-2. As a result, the position behind the detection end position of the identification pattern 43-1 of the track # 1 by a predetermined amount of data with respect to the track # 1, ie, 90 (10 + 30 + 10 + 30 + 10) data later, is the separation pattern 44 of the track # 1. Information indicating that the head position is −1 is obtained.

  Next, the identification information detector 232 detects the identification pattern 43-2 included in the reproduction signal 64 of the track # 2 in the reproduction signal # 2 of the reproduction head R-2. As a result, the position after the detection end position of the identification pattern 43-2 of the track # 2 by a predetermined amount of data with respect to the track # 2, ie, 120 (10 + 30 + 10 + 60 + 10) data, is the separation pattern 44 of the track # 2. -2 is obtained.

  As shown in FIG. 11, when there is a downward off-track, the reproduction head R-2 reproduces the first preamble and the second preamble of the track # 2 and the track # 3. At this time, the identification information detection unit 232 first detects the identification pattern 43-2 included in the reproduction signal 64 of the track # 2 in the reproduction signal # 2 of the reproduction head R-2. As a result, the position after the detection end position of the identification pattern 43-2 of the track # 2 by a predetermined amount of data with respect to the track # 2, ie, 120 (10 + 30 + 10 + 60 + 10) data, is the separation pattern 44 of the track # 2. -2 is obtained.

  Next, the identification information detection unit 232 detects the identification pattern 43-3 included in the reproduction signal 65 of the track # 3 in the reproduction signal # 2 of the reproduction head R-2. As a result, the position after the detection end position of the identification pattern 43-3 of the track # 3 by a predetermined amount of data with respect to the track # 3, that is, 150 (10 + 60 + 10 + 60 + 10) data later, is the separation pattern 44 of the track # 3. -3 information is obtained.

  As described above, even when there is an off-track in any of the upward and downward directions, the corresponding track separation is performed for each of the detected identification patterns 43-1, 43-2, and 43-3. The head positions of the patterns 44-1, 44-2, and 44-3 can be known more accurately, and information necessary for channel estimation calculation can be obtained effectively. Thereby, the quality of the signal separation process can be improved, and a high track density can be realized.

  FIG. 12 is a diagram showing a modification of the track format of FIG. In this track format, the number of tracks constituting the unit and the number of reproducing heads are four. The arrangement of the first preamble 23 and the second preamble 24 in the tracks # 1, # 2, # 3, and # 4 is the same as that in FIG. 7, but the direction in which the track of the first preamble 23 in the track # 4 proceeds The position at is the same as the position of the first preamble 23 of track # 1. The reproducing head R-1 reproduces the signal across the tracks # 1 and # 2, and the reproducing head R-2 reproduces the signal across the three tracks # 1, # 2, and # 3. Head R-3 reproduces a signal across three tracks # 2, # 3, and # 4, and reproduction head R-4 reproduces a signal across tracks # 3 and # 4. The head width and arrangement of the reproducing heads R-1, R-2, R-3, and R-4 are determined. Even in such a format, identification patterns 43-1, 43-2, 43-3, 43-4 are added to the first preamble 23 of each track # 1, # 2, # 3, and # 4. By identifying each track based on the original, it is possible to know more accurately the start position of the separation pattern of the corresponding track for each detected identification pattern, and the information necessary for channel estimation calculation is effective. Can get to.

  By the way, in the format of FIG. 7, the identification patterns 43-1, 43-2, and 43-3 of the tracks # 1, # 2, and # 3 are mutually adjacent in the direction in which the tracks progress between adjacent tracks in the unit. However, the present invention is not limited to this, and a code string that does not interfere with each other between adjacent tracks in the unit at the time of reproduction is adopted as the code pattern of the identification pattern. As a result, the identification patterns 43-1, 43-2, and 43-3 in the tracks # 1, # 2, and # 3 can be arranged at the same position in the traveling direction of the track.

  FIG. 13 shows an example of a format in which a code string in which the adjacent ones in the track width direction do not interfere with each other during reproduction is adopted for the first preamble 23. In the figure, reference numeral 41 denotes a range of gain control patterns 41-1, 41-2, and 41-3 in the first preamble 23, reference numeral 42 denotes a range of synchronization patterns 42-1, 42-2, and 42-3, Reference numeral 43 is a range of identification patterns 43-1, 43-2, 43-3.

  In this format, the respective patterns in the first preamble 23 of the tracks # 1, # 2, and # 3 are arranged at the same position in the track traveling direction. Such a format is more suitable, for example, when used in a recording apparatus that can record signals at the same recording position. In this case, the gain control patterns 41-1, 41-2, 41-3, In addition, the synchronization patterns 42-1, 42-2, and 42-3 can be given similar patterns. The identification patterns 43-1, 43-2, and 43-3 are code strings that are adjacent to each other in the track width direction so that they do not interfere with each other during reproduction.

As a code string used for the identification patterns 43-1, 43-2, 43-3, for example, 15 bits are given as an identification pattern,
As the identification pattern “1_1” of track # 1, 000001-010-000-000 is given,
As the identification pattern “1_2” of track # 2, 000001-000-010-000 is given,
000001-000-000-010 is given as the identification pattern “1_3” of the track # 3. Here, the upper 6 bits are a unit number code string, and the lower 9 bits are a track number code string.

  Thus, the code strings of the identification patterns 43-1, 43-2, and 43-3 of the tracks # 1, # 2, and # 3 are selected so that detection can be performed even when playback is performed across a plurality of tracks. By doing so, the identification patterns 43-1, 43-2, and 43-3 of the tracks # 1, # 2, and # 3 can be arranged at the same position in the direction in which the tracks travel.

  FIG. 14 shows another example of a format in which code strings that are adjacent to each other in the track width direction do not interfere with each other during reproduction are used for the identification patterns 43-1, 43-2, and 43-3. In the figure, reference numeral 41 denotes a range of gain control patterns 41-1, 41-2, and 41-3 in the first preamble 23, reference numeral 42 denotes a range of synchronization patterns 42-1, 42-2, and 42-3, Reference numeral 43 is a range of identification patterns 43-1, 43-2, 43-3.

In this format, as a code string used for the identification patterns 43-1, 43-2, 43-3, for example, 10 bits are given as the identification pattern,
As the identification pattern “1_1” of track # 1, 000001-0001 is given,
As the identification pattern “1_2” for track # 2, 000001-1000 is given,
000001-0010 is given as the identification pattern “1_3” of the track # 3. Here, the upper 6 bits are a unit number code string, and the lower 4 bits are a track number code string.

  Thus, the code strings of the identification patterns 43-1, 43-2, and 43-3 of the tracks # 1, # 2, and # 3 are selected so that detection can be performed even when playback is performed across a plurality of tracks. By doing so, the identification patterns 43-1, 43-2, and 43-3 of the tracks # 1, # 2, and # 3 can be arranged at the same position in the direction in which the tracks travel.

  As described above, according to this embodiment, the identification patterns 43-1, 43-2, and 43-3 are arranged in the first preamble 21 of each track, and these identification patterns 43-3 are reproduced during data reproduction. 1, 43-2, 43-3 is detected to identify the track, and the track separation pattern 44-1 corresponding to the detected identification pattern 43-1, 43-2, 43-3, respectively. , 44-2, 44-3 can be known more accurately, and information necessary for channel estimation calculation can be obtained effectively. Thereby, the quality of the signal separation process can be improved, and a high track density can be realized.

  Next, a modification of this embodiment is shown.

  The above has been described on the assumption that the width of the reproducing head is 1.5 times the track width, and each reproducing head is arranged so that each reproducing head performs reproduction over a plurality of tracks. The position of each reproducing head in the track width direction may be controlled so that each reproducing head is arranged across a plurality of tracks. Thereby, even if the width of the reproducing head is made narrower, it is possible to ensure a state where each reproducing head straddles a plurality of tracks.

  In the description so far, the identification pattern is added to the first preamble as a separate pattern with respect to the gain control pattern and the synchronization pattern, but a plurality of types of patterns are prepared for the synchronization pattern. By associating identification information with each type of the synchronization pattern, it may be possible to simultaneously detect the synchronization pattern and acquire the identification information. Further, the identification information may be obtained by the position of the pattern in the first preamble.

  In the above embodiment, the separation pattern as shown in FIG. 7 is used as a pattern necessary for detecting the positional relationship in the track width direction during reproduction between each reproduction head and a plurality of tracks for one unit. However, the present invention is not limited to this, and for example, tracking servo information can be used. In this case, a summary of the positional relationship between each recording pattern of the tracking servo information and each reproducing head in units is generated as channel estimation information.

  Further, the channel estimation calculation may be performed using both the means for detecting the positional relationship using the separation pattern and the means for detecting the positional relationship using the tracking servo information.

  Furthermore, in the above embodiment, a case where a matrix of 3 rows and 3 columns or 4 rows and 4 columns is calculated as the channel estimation information has been described. However, even if it is another square matrix, by obtaining its generalized inverse matrix Signal separation processing can be performed. Furthermore, a generalized inverse matrix may be obtained in the same manner for a matrix other than a square matrix.

  Note that the type of separation pattern needs to correspond to the number of tracks in order to obtain a generalized inverse matrix.

  The separation pattern is a pattern having the number of tracks that are primary independent of each other. For example, when the number of recording heads is 3 and the number of reproducing heads is 4, that is, when the number of recording tracks is 3 and the number of reproducing signals is 4, there are three types of separation patterns that are primarily independent of each other. It is assumed to be composed of the following pattern.

  The amount of information for gain control may be increased by additionally arranging the gain control pattern arranged in the first preamble behind the synchronization pattern.

  The same pattern may be adopted as the gain control pattern arranged in the first preamble and the separation pattern arranged in the second preamble.

  In the above embodiment, the separation pattern orthogonal to the time axis is used. However, the present invention is not limited to this. For example, a separation pattern orthogonal to the frequency axis or an orthogonal code is used. A separated pattern may be used.

  As a calculation method of signal separation processing by the signal separation calculation unit 236, for example, a method for obtaining a generalized inverse matrix for a channel matrix can be cited. A method for obtaining a generalized inverse matrix for this channel matrix is generally called a zero-forcing method. However, the method of signal separation processing is not limited to this, and for example, the MMSE (Minimum Mean Squared Error) method can also be used.

  In the above embodiment, the magnetic recording / reproducing system has been described in which a signal is recorded on the magnetic recording medium without aligning the recording position for each track, and the signal is reproduced from the magnetic recording medium without aligning the reproducing position for each track. The present invention is not limited to this, for example, a magnetic recording / reproducing method for recording a signal without aligning the recording position for each track, and reproducing from the magnetic recording medium by aligning the reproducing position for each track. The same applies to the above. Further, the present invention can be similarly applied to a magnetic recording / reproducing system in which a signal is recorded with the recording position aligned for each track, and reproduction is performed from the magnetic recording medium without aligning the reproducing position for each track.

  (Second Embodiment)

  Next, a magnetic recording / reproducing system using a single head will be described as a second embodiment of the present invention.

  The magnetic recording / reproducing system of this embodiment has a recording head and a reproducing head whose number is less than the number of tracks per unit or a unit, and a recording medium on which recording is performed without aligning the recording position for each track. This is a method of reproducing without arranging the reproduction position every time.

  FIG. 15 is a diagram showing a configuration of a recording apparatus 300 in the magnetic recording / reproducing system according to the second embodiment of the present invention.

  The recording apparatus 300 performs unit recording with a single head. Here, the predetermined number of times that the unit is recorded by one recording head is M, and the predetermined number of times that the unit is reproduced by one reproducing head is N.

  As shown in the figure, the recording apparatus 300 includes a multitracking unit 110, a multitrack recording encoding unit 120, a multitrack preamble adding unit 130, a multitrack recording unit 140, a recording head array 150, and a storage unit 149. Is done.

  The multitrack recording encoding unit 120 includes M recording encoding units 121-1, 121-2, and 121-3 that encode the recording data allocated to M by the data distributor 111.

  The multitrack preamble adding unit 130 adds M preambles necessary for controlling data reproduction in units of units to each recording data encoded by the multitrack recording encoding unit 120. 1, 131-2, 131-3.

  The storage unit 149 stores a code string of recording data for at least one unit generated by the multitrack preamble adding unit 130.

  The multi-track recording unit 140 is a means for recording the recording code string of each track to which the preamble is added on the recording medium. More specifically, the multi-track recording unit 140 is a single unit that gives a desired timing to the recording code string to which the preamble is added. An output timing setting unit 141, one recording compensation unit 144 that performs recording compensation processing, one recording amplifier 147 that drives each recording head W-1 based on the recording code string after the recording compensation processing, and Consists of.

  FIG. 16 is a flowchart showing a flow of operations during unit recording of the recording apparatus 300.

  In the recording apparatus 300, first, the input recording data 1 is distributed to M (M = 3) pieces of data (data for each track) by the multitracking unit 110 (step S301).

  Each distributed data is encoded into a code string in consideration of recording / reproducing characteristics of the magnetic recording medium 2 by the recording encoding units 121-1, 121-2, and 121-3 of the multi-track recording encoding unit 120, respectively. Is done. At this time, information necessary for data demodulation, such as a demodulation synchronization pattern, is also added to the code string (step S302).

  Next, at a predetermined position of each encoded recording data, the M independent preamble adding units 131-1, 131-2, 131-3 of the multi-track preamble adding unit 130 store the unit unit data. A pattern necessary for reproduction control is added as a preamble, and a recording code string is obtained (step S303). The recording code string for each track to which the preamble is added in this way is stored in the storage unit 149 (step S304).

  Thereafter, the recording code string of the track to be recorded first is read from the storage unit 149 (step S305), and a desired timing is given to the recording code string of this track by the output timing setting unit 141. The recording compensation unit 144 performs a recording compensation process for optimizing the recording on the magnetic recording medium 2, the recording amplifier 147 converts the voltage into a current, and the recording head W-1 converts the magnetic recording medium 2. (Step S306).

  Thereafter, it is determined whether or not the recording of one unit of track has been completed (step S307). If not completed (NO in step S307), the recording head W-1 is moved to the next position (step S308). ). Thereafter, the recording code string of the next track is read from the storage unit 149, and the processing for recording is similarly repeated. The above operation is repeated until recording of a track for one unit is completed.

  Next, a modification of the recording apparatus in the magnetic recording / reproducing system of the second embodiment will be shown.

  FIG. 17 is a diagram showing a configuration of a recording apparatus 301 which is a modification of the recording apparatus in the magnetic recording / reproducing system of the second embodiment.

  As shown in the figure, the recording apparatus 301 is different from the recording apparatus 300 in FIG. 15 in the configuration of a multitrack recording encoding unit 120 and a multitrack preamble adding unit 130. The multitrack recording encoding unit 120 includes a recording encoding unit 121 that records and encodes recording data in a predetermined unit, for example, recording data for a predetermined number of tracks. The multitrack preamble adding unit 130 includes an independent preamble adding unit 131 that adds a preamble necessary for controlling data reproduction in units of units to encoded recording data for each track. Further, in this recording apparatus 301, the multitracking unit 110 (data distributor 111) is omitted from the configuration of the recording apparatus 300 shown in FIG.

  FIG. 18 is a flowchart showing a unit recording operation flow of the recording apparatus 301.

  In this recording apparatus 301, first, recording data in a predetermined unit, for example, recording data for a predetermined number of tracks, is encoded into a code string in consideration of recording / reproduction characteristics of the magnetic recording medium 2 by the recording encoding unit 121. Is done. At this time, information necessary for data demodulation such as a synchronization pattern for demodulation is also added to the data code string (step S311).

  Next, the independent preamble adding unit 131 adds a pattern necessary for control of reproducing the data in units at a predetermined position of each encoded recording data as a preamble, thereby obtaining a recording code string. (Step S312). The recording code string for each track to which the preamble code is added in this way is stored in the storage unit 149 (step S313).

  Thereafter, the recording code string of the track to be recorded first is read from the storage unit 149 (step S314), and a desired timing is given to the recording code string of this track by the output timing setting unit 141, and then the recording is performed. The compensation unit 144 performs a recording compensation process for optimizing the recording on the magnetic recording medium 2, and the recording amplifier 147 converts the voltage into a current. The recording head W-1 applies the recording compensation process to the magnetic recording medium 2. It is recorded (step S315).

  Thereafter, it is determined whether or not recording of one unit of track has been completed (step S316). If not completed (NO in step S316), the recording head W-1 is moved to the next position (step S317). ), The recording code string of the next track is read from the storage unit 149, and the recording process is repeated in the same manner. The above operation is repeated until recording of a track for one unit is completed.

  For example, when the track format shown in FIG. 7 is used, first, the track # 1 is moved to the track # 1, and the track # 1 is recorded. Thereafter, the track # 2 is moved to the track # 2, and the track # 2 is recorded. And finally move to the position of track # 3 to record track # 3.

  Next, a reproducing apparatus in the magnetic recording / reproducing system according to the second embodiment of the present invention will be described.

  FIG. 19 is a diagram showing a configuration of a reproducing apparatus 400 in the magnetic recording / reproducing system according to the second embodiment of the present invention.

  As shown in the figure, the reproducing apparatus 400 includes a reproducing head array 210, a channel reproducing unit 220, a signal separation processing unit 230, a multitrack demodulation unit 240, and a restoration unit 260.

  The reproducing head array 210 has one reproducing head R-1 that reads a signal from each track recorded on the magnetic recording medium 2.

  The channel reproducing unit 220 amplifies the signal reproduced by the reproducing head R-1 mounted on the reproducing head array 210, and the amplitude level of the output of the reproducing amplifier 221 becomes a predetermined value. And a gain adjuster 224 for controlling the gain, and an A / D converter 225 for quantizing the output of the gain adjuster 224 into a digital value having a predetermined bit width.

  The signal separation processing unit 230 includes a synchronization signal detection unit 231, an identification information detection unit 232, a reproduction signal gain control processing unit 233, a channel estimation calculation unit 234, a reproduction position control processing unit 235, a signal separation calculation unit 236, and a storage unit. 237.

  The synchronization signal detection unit 231 detects a synchronization pattern in the preamble from the reproduction signal of the reproduction head R-1 output from the A / D converter 225.

  The identification information detection unit 232 uses the information obtained by the synchronization signal detection unit 231 to identify and detect the leading position of the identification pattern in the reproduction signal of the reproduction head R-1, and outputs the identification information.

  The reproduction signal gain control processing unit 233 detects the gain control pattern in the preamble from the reproduction signal of the reproduction head R-1 for each scan from the storage unit 237, and reproduces for each scan based on the gain control pattern. The gain for the reproduction signal of the head R-1 is calculated to control the level of the reproduction signal of the reproduction head R-1 for each scan.

  The channel estimation calculation unit 234 uses the synchronization pattern detected by the synchronization signal detection unit 231 to identify the start position of the separation pattern included in the preamble of the reproduction signal of the reproduction head R-1 for each scan, and Using the separation pattern, channel estimation calculation is performed to calculate a channel matrix corresponding to the positional relationship in the track width direction during reproduction between the reproduction head R-1 and a plurality of tracks for each scan.

  The reproduction position control processing unit 235 matches the reproduction position of the reproduction signal of the reproduction head R-1 for each scan that has passed through the reproduction signal gain control processing unit 233 based on the information obtained by the synchronization signal detection unit 231. I do.

  The signal separation calculation unit 236 calculates an inverse matrix using the channel matrix obtained by the channel estimation calculation unit 234, and uses this inverse matrix to reproduce the reproduction signal for one unit input from the reproduction position control processing unit 235. Then, the process of separating the reproduction signal for each track is performed.

  The storage unit 237 is disposed behind the synchronization signal detector 231 and stores a reproduction signal for at least one unit.

  As shown in FIG. 4, the multi-track demodulation unit 240 performs M equalizers 241-1 and 241− that perform equalization processing on the reproduction signal for each track separated by the signal separation operation unit 236. 2, 241-3, M PLLs 242-1, 242-2, and 242-3 that perform bit synchronization from the outputs of the equalizers 241-1, 241-2 and 241-3, and PLLs 242-1 and 242- For example, M detection units 243-1, 243-2, and 243 such as a Viterbi detection unit generate a code string by binarizing the reproduction signal of each track using the bit synchronization signal generated in 2,242-3. -3 and M synchronization signal detection units 244-1 and 244 for detecting a synchronization signal on the code string from the binarized reproduction signals output from the detection units 243-1, 243-2 and 243-3 -2, 244-3 and sync signal detection M decoders 245-1, 245-2, which specify the head position of data based on the synchronization patterns detected by 244-1, 244-2 and 244-3 and decode the data string from the code string. 245-3. Note that the multitrack demodulation unit 240 has a storage unit (not shown) that stores information such as data necessary for performing the above processing.

  Referring back to FIG. 19, the restoration unit 260 performs the reverse operation of recording the data of each track output from the M decoders 245-1, 245-2, and 245-3 in the multitrack demodulation unit 240. And a data combiner 261 for recovering the reproduction data 3 by connecting them.

  Note that the track scanning during reproduction by the single head is repeated at least as many times as the number of recording tracks of one unit. In other words, scanning may be repeated more times than the number of tracks. At this time, all the tracks for one unit are scanned at least once. The storage unit 237 stores a signal corresponding to a unit reproduced at each position where the reproducing head R-1 has moved, that is, a signal reproduced by the reproducing head R-1 from a plurality of tracks at each position, and a synchronization signal detector 231. Thus, the necessary reproduction signal after the separation pattern is stored.

  FIG. 20 is a flowchart showing the unit reproduction operation of the reproduction apparatus 400.

  In the reproducing apparatus 400, first, signals are reproduced from a plurality of tracks at the initial position by the reproducing head R-1 (step S401). Next, after the amplitude level of the output of the reproduction amplifier 221 is adjusted by the gain adjusting unit 224, the output is converted into a digital value by the A / D converter 225 and output to the synchronization signal detector 231 ( Step S402).

  Next, after the synchronization signal detection unit 231 detects the synchronization pattern included in the reproduction signal output from the A / D converter 225 (step S403), the identification information detection unit 232 performs the synchronization signal detection unit. Using the synchronization pattern detected by H.231, the head position of the identification pattern in the reproduction signal of the reproduction head R-1 is specified to obtain identification information (step S404). The reproduction signal that has passed through the identification information detection unit 232 is stored in the storage unit 237 (step S405).

  Next, it is determined whether or not the reproduction signal for one unit is stored in the storage unit 237 (step S406). If the reproduction signal for one unit is not yet stored in the storage unit 237, the reproduction head R- 1 is shifted to the next position in the track width direction (step S407), and the operations from step S401 to step S405 are repeated.

  When the reproduction signal for one unit is stored in the storage unit 237, the reproduction signal gain control processing unit 233 reads out the reproduction signal for one unit stored in the storage unit 237 and arranges it in the reproduction signal for each scan. Based on the gain control pattern, the gain for the reproduction signal for each scan is calculated to control the level of the reproduction signal for each scan (step S408).

  Next, based on the synchronization pattern detected by the synchronization signal detection unit 231 and the identification information obtained by the identification information detection unit 232 in the channel estimation calculation unit 234, the reproduction signal of the reproduction head R-1 for each scan A channel corresponding to the positional relationship in the track width direction at the time of reproduction between the reproduction head R-1 and a plurality of tracks for each scan is specified using the separation patterns. A matrix is calculated (step S409).

  Next, the reproduction position control processing unit 235 passes through the reproduction signal gain control processing unit 233 based on the synchronization pattern detected by the synchronization signal detection unit 231 and the identification information obtained by the identification information detection unit 232. The reproduction position of the reproduction signal of the reproduction head R-1 for each scan is aligned (step S410).

  Next, the signal separation calculation unit 236 calculates an inverse matrix of the channel matrix obtained by the channel estimation calculation unit 234, and uses this inverse matrix for one unit output from the reproduction signal gain control processing unit 233. The process of separating the reproduction signal for each track from the reproduction signal is performed (step S411).

  After this, the multi-track demodulator 240 decodes the data sequence from the reproduction signal separated for each track (step S412), and the reconstruction unit 260 concatenates the data for each track to obtain reproduction data 3. (Step S413).

  Note that a low-pass filter that removes unnecessary high-frequency components may be provided immediately before the A / D converter 225 as necessary. Further, the gain adjusting unit 224 may be connected to the subsequent stage of the A / D converter 225 to control the gain after quantization. This is effective when it is desired to use the bit width of the A / D converter 225 more effectively, or to make the configuration of the gain adjustment unit 224 simple in consideration of the detection of each pattern included in the preampule. Alternatively, the gain adjustment unit 224 may perform gain adjustment using information obtained by taking an error from the target gain value in the synchronization signal detector 231.

  Further, if the multitrack demodulator 240 performs the demodulation process while controlling the output timing for each track, the data concatenation process in the restoration unit 260 becomes unnecessary. Therefore, in this case, the restoration unit 260 is not necessary.

  The present invention is not limited to the linear recording system and non-azimuth recording system magnetic recording / reproduction described above, but can also be applied to a helical recording system and an azimuth recording system.

  Specific examples are shown below.

  FIG. 21 shows recording on the magnetic recording medium 2 by a non-azimuth method and a helical scan method using a plurality of recording heads W-1, W-2, and W-3 integrated as a recording head array 150, for example. It is a conceptual diagram of a track format. Also in the helical scan method, a guard band 52 is disposed between unit-configured track rows 53 composed of track # 1, track # 2, and track # 3. The preamble 21 recorded on the track # 1, the track # 2, and the track # 3 may be the same as those shown in FIGS. 7 and 12, for example. The present invention can also be applied to such a helical scan magnetic recording / reproducing method, and the configurations of the recording device 100 and the reproducing device 200 in the magnetic recording / reproducing method of the first embodiment can be employed.

  FIG. 22 shows recording on a recording medium by a double azimuth method and a helical scan method using a plurality of recording heads W-1, W-2, W-3, W-4, W-5, and W-6. It is a conceptual diagram of a track format. In helical scan magnetic recording, a plurality of heads are independently mounted on a rotating drum. For example, a plurality of recording heads and a reproducing head are alternately arranged on a rotating drum.

  In this example, six recording heads W-1, W-2, W-3, W-4, W-5, and W-6 are used for recording and reproduction, respectively. Of these recording heads, the three consecutive recording heads W-1, W-2, and W-3 and the remaining three consecutive recording heads W-4, W-5, and W-6 are mutually connected to each other. The azimuth direction, which is the magnetization direction, is made different. That is, track # 1- # 3 and track # 4- # 6 have different azimuth directions. These tracks # 1 to # 6 form a unit configuration track row 53 including a plurality of units as a unit of processing for reproducing data. In the case of this double azimuth, no guard band is required.

  In this example, a group of tracks # 1 to # 6 is a unit of signal processing for reproducing data. However, three consecutive tracks (for example, track # 1) having the same azimuth direction are used. -# 3 and tracks # 4- # 6) may each be subjected to signal processing as one unit.

  The preamble recorded on each track # 1- # 6 may be the same as that shown in FIGS. 7 and 12, for example. The present invention can also be applied to such a magnetic recording / reproducing system of the double azimuth method and the helical scan method, and the configuration of the recording apparatus 100 and the reproducing apparatus 200 in the magnetic recording / reproducing system of the first embodiment is adopted. be able to.

  It should be noted that the present invention is not limited to the configuration shown in the above-described embodiment, and it is needless to say that various changes and modifications can be made without departing from the technical scope described in the claims.

It is a figure which shows the structure of the recording device in the magnetic recording / reproducing system of the 1st Embodiment of this invention. 3 is a flowchart showing an operation of unit recording by the recording apparatus of FIG. 1. It is a figure which shows the structure of the reproducing | regenerating apparatus in the magnetic recording / reproducing system of the 1st Embodiment of this invention. FIG. 4 is a diagram illustrating a configuration of a multitrack demodulator in the playback device of FIG. 3. 4 is a flowchart showing an operation of unit playback by the playback device of FIG. 3. FIG. 2 is a conceptual diagram of a track format on a magnetic recording medium on which recording is performed by the recording apparatus of FIG. 1. FIG. 7 is a diagram illustrating a configuration of a preamble in the track format of FIG. 6. It is a figure which shows the comparative example with respect to the track format concerning this invention. It is a figure which shows the reproduction signal of each reproduction head when there is no off-track. It is a figure which shows the example of the reproduction signal of each reproduction head when the position of the reproduction head is shifted upward. It is a figure showing an example of a reproduction signal of each reproduction head when the position of the reproduction head is shifted downward. It is a figure which shows the other example of the track format of FIG. It is a figure which shows the further another example of the track format of FIG. It is a figure which shows the further another example of the track format of FIG. It is a figure which shows the structure of the recording device in the magnetic recording / reproducing system of the 2nd Embodiment of this invention. FIG. 16 is a flowchart showing an operation flow during unit recording of the recording apparatus of FIG. 15. FIG. It is a figure which shows the modification of the recording device of FIG. It is a flowchart which shows the flow of operation | movement at the time of unit recording of the recording device of FIG. It is a figure which shows the structure of the reproducing | regenerating apparatus in the magnetic recording / reproducing system of the 2nd Embodiment of this invention. FIG. 20 is a flowchart showing an operation of unit playback by the playback apparatus of FIG. It is a conceptual diagram of a track format recorded on a magnetic recording medium by a non-azimuth method and a helical scan method using a plurality of recording heads. It is a conceptual diagram of a track format recorded on a recording medium by a double azimuth method and a helical scan method using a plurality of recording heads. It is a figure which shows the structure of the recording apparatus which employ | adopted the magnetic recording and reproducing system which the present inventors proposed in the past. It is a flowchart which shows the operation | movement of unit recording by the recording device of FIG. It is a figure which shows the structure of the reproducing | regenerating apparatus which employ | adopted the magnetic recording / reproducing system which the present inventors proposed in the past. FIG. 26 is a flowchart showing a flow of unit reproduction operation of the reproduction apparatus of FIG. 25. FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Recording data 2 Magnetic recording medium 3 Reproduction data 21 Preamble 22 Data 23 1st preamble 24 2nd preamble 41-0, 41-1, 41-3 Gain control pattern 42-0, 42-1, 42-3 Synchronization Pattern 43-0, 43-1, 43-3 Identification pattern 44-1, 44-2, 44-3 Separation pattern 51 Unit 100 Recording device 110 Multitracking unit 111 Data distributor 120 Multitrack recording encoding unit 121- 1, 121-2, 121-3 Recording Encoding Unit 130 Multitrack Preamble Adding Units 131-1, 131-2, 131-3 Independent Preamble Adding Units 132-1, 132-2, 132-3 Preamble Adding Unit 140 Multi Track recording unit 141-1, 141-2, 141-3 output timing Fixed section 144-1, 144-2, 144-3 Recording compensation sections 147-1, 147-2, 147-3 Recording amplifier 149 Storage section 150 Recording head array 200 Playback apparatus 210 Playback head array 220 Channel playback section 221-1 , 221-2, 221-3 Regenerative amplifiers 224-1, 224-2, 224-3 Gain adjusting units 225-1, 225-2, 225-3 A / D converter 230 Signal separation processing unit 231 Synchronization signal detector 232 Identification information detection unit 233 Playback signal gain control processing unit 234 Channel estimation calculation unit 235 Playback position control processing unit 236 Signal separation calculation unit 237 Storage unit 240 Multitrack demodulation units 241-1, 241-2, 241-3 Equalizer 243 -1,243-2, 243-3 detectors 244-1, 244-2, 244-3 synchronization signal detector 24 -1,245-2,245-3 decoder 260 restores 261 the data coupler R-1, R-2, R-3 reproducing heads W-1, W-2, W-3 recording head

Claims (20)

A track format in which data can be reproduced by a reproducing apparatus having a reproducing head capable of reproducing a signal across a plurality of tracks,
It has a plurality of tracks constituting a unit that is a unit of signal processing for data reproduction, and each of the plurality of tracks can individually identify itself with respect to data and other tracks. And a preamble including a separation pattern necessary for detecting a positional relationship in the track width direction during reproduction between the reproducing head and the plurality of tracks. Track format. The track format according to claim 1,
The track format characterized in that the identification information includes information for identifying the unit. The track format according to claim 1,
The track format is characterized in that the identification information is arranged in the preamble as an identification pattern. The track format according to claim 3, wherein
The track format is characterized in that the identification patterns of the tracks are arranged so as to be shifted from each other in adjacent directions in the unit in the traveling direction of the tracks. The track format according to claim 3, wherein
The track format is characterized in that the identification pattern of each track is a pattern which does not interfere between adjacent tracks in the unit. The track format according to claim 3, wherein
The preamble further includes a gain control pattern for controlling gains of the plurality of reproduction signals reproduced by the reproduction head, and a synchronization pattern for synchronizing the plurality of reproduction signals. Track format. The track format according to claim 1,
The preamble added by the multitrack preamble adding unit is synchronized with a gain control pattern for controlling the gains of the plurality of reproduction signals reproduced by the reproduction head and the plurality of reproduction signals. A track format, wherein the identification information is given by a combination of a plurality of types of the synchronization patterns. A recording medium capable of reproducing data by a reproducing apparatus having a reproducing head capable of reproducing a signal across a plurality of tracks,
It has a plurality of tracks constituting a unit that is a unit of signal processing for data reproduction, and each of the plurality of tracks can individually identify itself with respect to data and other tracks. And a preamble including a separation pattern necessary for detecting a positional relationship in the track width direction during reproduction between the reproducing head and the plurality of tracks. recoding media. A recording apparatus for recording a plurality of tracks constituting a unit which is a unit of signal processing for data reproduction on a recording medium,
A multi-track recording encoding unit for encoding data to be recorded for each track;
Identification information for enabling individual identification of each track in the code string of the data for each track encoded by the multi-track recording encoding unit, and a playback device A multi-track preamble that is provided and adds a preamble including a separation pattern necessary for detecting a positional relationship in a track width direction during reproduction between the reproduction head capable of reproducing a signal across a plurality of tracks and the plurality of tracks. An additional part;
A recording apparatus comprising: a multitrack recording unit that records data for each track, to which the preamble is added by the multitrack preamble adding unit, on the recording medium by a recording head. The recording apparatus according to claim 9, wherein
The recording apparatus, wherein the identification information includes information for identifying the unit. The recording apparatus according to claim 9, wherein
The recording apparatus according to claim 1, wherein the preamble added by the multitrack preamble adding unit includes the identification information as an identification pattern. The recording apparatus according to claim 11,
The multi-track preamble adding unit converts the identification pattern of each track from the adjacent tracks in the unit so as to be shifted from each other in the traveling direction of the track. A recording apparatus characterized by being added. The recording apparatus according to claim 11,
The recording apparatus according to claim 1, wherein the multi-track preamble adding unit uses a pattern that does not interfere between adjacent tracks in the unit as the identification pattern of each track. The recording apparatus according to claim 11,
The preamble added by the multitrack preamble adding unit is synchronized with a gain control pattern for controlling the gains of the plurality of reproduction signals reproduced by the reproduction head and the plurality of reproduction signals. And a pattern. The recording apparatus according to claim 9, wherein
The preamble added by the multitrack preamble adding unit is synchronized with a gain control pattern for controlling the gains of the plurality of reproduction signals reproduced by the reproduction head and the plurality of reproduction signals. A recording apparatus, wherein the identification information is given by a combination of a plurality of types of synchronization patterns. A method of recording a plurality of tracks constituting a unit which is a unit of signal processing for data reproduction on a recording medium,
Encoding data to be recorded for each track;
Each of the encoded code strings of the data for each of the tracks is identification information for enabling individual identification with respect to other tracks, and the reproduction head and the plurality of tracks. Adding a preamble including a separation pattern necessary for detecting the positional relationship in the track width direction during reproduction;
Recording the data for each track to which the preamble is added onto the recording medium by the recording head. It has a plurality of tracks that constitute a unit that is a unit of signal processing for data reproduction, and each of the plurality of tracks can individually identify itself with respect to data and other tracks And a preamble including a separation pattern necessary for detecting a positional relationship in a track width direction during reproduction between the reproduction head capable of reproducing a signal across the plurality of tracks and the plurality of tracks. Is a reproducing device for reproducing a recording medium on which is recorded,
An identification information detection unit for detecting identification information for each track from the signal reproduced by the reproduction head;
In consideration of the identification information for each track detected by the identification information detector, the position of the separation pattern for each track is specified, and the reproduction head is based on the reproduction signal of the separation pattern for each unit. And a channel estimation calculation unit for calculating a channel matrix corresponding to the positional relationship in the track width direction during reproduction with the plurality of tracks. The playback device according to claim 17, wherein
A signal separation calculation unit that separates the reproduction signal of the data for each track from the reproduction signal of the data for one unit reproduced by the reproduction head using the channel matrix obtained by the channel estimation calculation unit And a playback apparatus. It has a plurality of tracks that constitute a unit that is a unit of signal processing for data reproduction, and each of the plurality of tracks can individually identify itself with respect to data and other tracks And a preamble including a separation pattern necessary for detecting a positional relationship in a track width direction during reproduction between the reproduction head capable of reproducing a signal across the plurality of tracks and the plurality of tracks. Is a method of reproducing a recording medium on which is recorded,
Detecting identification information for each track from the signal reproduced by the reproduction head;
The position of the separation pattern for each track is specified in consideration of the detected identification information for each track, and the reproduction head and the plurality of tracks are determined based on the reproduction signal of the separation pattern for each unit. And a step of calculating a channel matrix corresponding to the positional relationship in the track width direction during playback. A recording apparatus for recording a plurality of tracks constituting a unit which is a unit of signal processing for data reproduction on a recording medium,
A multi-track recording encoding unit for encoding data to be recorded for each track;
Identification information for enabling individual identification of each track in the code string of the data for each track encoded by the multi-track recording encoding unit, and a playback device A multi-track that is provided and adds a preamble including a separation pattern necessary for detecting a positional relationship in a track width direction at the time of reproduction between the reproducing head capable of reproducing a signal across the plurality of tracks and the plurality of tracks A preamble adding unit;
A recording apparatus comprising: a multitrack recording unit that records data for each of the tracks, to which the preamble is added by the multitrack preamble adding unit, on the recording medium by a recording head;
A playback device for playing back the recording medium recorded by the recording device,
An identification information detection unit for detecting identification information for each track from the signal reproduced by the reproduction head;
In consideration of the identification information for each track detected by the identification information detector, the position of the separation pattern for each track is specified, and the reproduction head is based on the reproduction signal of the separation pattern for each unit. And a channel estimation calculation unit for calculating a channel matrix corresponding to a positional relationship in the track width direction during reproduction with the plurality of tracks. A recording / reproducing apparatus comprising:

Images