JP2009032338A - Reproducing device, reproduction method, track format, recording medium, and recording and reproducing device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a reproducing device which can satisfactorily perform arithmetic operation of signal separation and can improve quality of reproduced data by preventing influence of a noise included in a reproduced signal on channel estimation arithmetic operation. <P>SOLUTION: On the basis of discrimination information obtained by a discrimination information detecting part 232, a separation pattern part processing control part 238 discriminates, for each reproduced signal of individual reproducing head in a section in which a separation pattern of a unit division is arranged, a reproduced signal corresponding to a section of a separation pattern reproduced by the reproducing head from a reproduced signal corresponding to the section of the separation pattern being not reproduced by the reproducing head. A channel estimation arithmetic operation part 234 uses the reproduced signal corresponding to the section of the separation pattern reproduced by the reproducing head as it is, and replaces the reproduced signal corresponding to the section of the separation pattern which is not reproduced by the reproducing head by the prescribed value and performs channel estimation arithmetic operation. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a reproducing apparatus, a reproducing method, a track format, a recording medium, and a recording / reproducing apparatus that reproduce data from 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. 25 is a diagram showing a configuration of a recording apparatus 800 that employs the magnetic recording / reproducing method described above.

  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. 26 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. 27 is a diagram showing a configuration of a reproducing apparatus 900 that employs the above 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. 28 is a flowchart showing a unit reproduction operation flow 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-described magnetic recording / reproducing method, the quality of the reproduced signal may be deteriorated due to disturbance or media noise during reproduction. This is the same for both the data portion and the preamble portion. Therefore, the quality of the reproduction signal of the separation pattern portion used when the signal separation processing is performed is similarly deteriorated.

  As a result of the deterioration of the quality of the reproduced signal of the separation pattern part, the quality of the channel estimation calculation for obtaining the channel matrix necessary for performing the signal separation calculation may deteriorate, and the signal separation processing may not be performed well. was there. 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 can reduce the influence of noise included in a reproduction signal on channel estimation calculation, perform signal separation calculation processing favorably, and improve the quality of reproduction data. A reproduction apparatus, a reproduction method, a track format, a recording medium, and a recording / reproduction apparatus are provided.

  In order to solve the above problems, the playback apparatus of the present invention has a plurality of tracks that constitute a unit that is a unit of signal processing for data playback, and each of the plurality of tracks includes data, A preamble including a separation pattern necessary for detecting a positional relationship between the reproduction head during reproduction and the plurality of tracks in the track width direction is recorded, and a plurality of separation patterns for each track are recorded by the reproduction head during reproduction. A playback apparatus for playing back a recording medium arranged by shifting a section in the traveling direction of the track so as not to be played back simultaneously, in a playback signal of the playback head in a section in which the separation pattern for the unit is placed At least, a reproduction signal corresponding to a section of the separation pattern that is not reproduced by the reproduction head is predicted. Substituting the determined value comprises the channel estimation calculation unit for calculating a channel matrix corresponding to the position relationship between the track width direction at the time of reproduction of the reproduction heads and the plurality of tracks.

  According to the present invention, in the reproduction signal of the reproduction head in the section where the separation pattern for the unit is arranged, at least the reproduction signal corresponding to the section of the separation pattern not reproduced by the reproduction head is replaced with a predetermined value. By performing the channel estimation calculation, it is possible to reduce the influence on the channel estimation calculation due to noise included in the reproduced signal in the section of the separation pattern for the unit. As a result, it is possible to satisfactorily perform signal separation arithmetic processing and realize high track density.

  The playback apparatus of the present invention determines, based on the playback signal from the playback head, which track the playback code string is played back from, and based on the determination result, the unit signal. In the reproduction signal of the reproduction head in the section where the separation pattern is arranged, the reproduction signal corresponding to the separation pattern section reproduced by the reproduction head and the section of the separation pattern not reproduced by the reproduction head It may further comprise discriminating means for discriminating each reproduction signal to be reproduced.

  Further, in the reproducing apparatus of the present invention, the preamble further includes an identification pattern for identifying a track, and the discriminating means records the recording code of which track the reproduction signal of the reproducing head is based on the identification pattern. It may be determined whether the signal is a reproduction of a column. Thereby, the track can be easily identified, and the discrimination between the reproduction signal corresponding to the section of the separation pattern reproduced by the reproduction head and the reproduction signal corresponding to the section of the separation pattern not reproduced by the reproduction head is good. Can be done.

  The reproduction apparatus of the present invention replaces the reproduction signal determined by the determination unit and corresponding to the section of the separation pattern that is not reproduced by the reproduction head with a predetermined value and outputs the replacement signal to the channel estimation calculation unit. Reproducing signal replacement means further, the channel estimation calculation unit, using the reproduction signal corresponding to the section of the separation pattern reproduced by the reproducing head and the reproduction signal replaced by the reproduction signal replacement means, The channel matrix may be calculated.

  The reproducing head may be capable of reproducing a signal across a plurality of tracks. The above effects can also be obtained when reproduction is performed using such a reproduction head.

  The reproduction apparatus of the present invention uses the channel matrix obtained by the channel estimation calculation unit to reproduce the data reproduction signal for each track from the data reproduction signal for the unit reproduced by the reproduction head. It may further comprise a signal separation operation unit for separating the signals. According to the present invention, it is possible to obtain a good channel estimation calculation result in which the influence of noise included in the reproduction signal in the separation pattern section is reduced, so that the signal separation processing can be performed satisfactorily and the high track density can be increased. realizable.

  In the reproducing apparatus of the present invention, a plurality of reproducing heads may be provided so that signals can be reproduced with different positional relationships with respect to the plurality of tracks for one unit. The above-described effect can be obtained even in a reproducing apparatus having a plurality of reproducing heads.

  Furthermore, in the playback device of the present invention, when playing back a recording medium in which the separation patterns of a plurality of tracks are arranged in the same section in the direction in which the tracks travel, the channel estimation calculation unit corresponds to the section. The channel matrix may be calculated using the reproduced signal to be used as the reproduced signal of the section and the virtual section. As a result, even a recording medium in which the separation patterns of a plurality of tracks are arranged in the same section in the direction in which the tracks travel can be satisfactorily reproduced.

  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 has data and reproduction at the time of reproduction. A preamble including a separation pattern necessary for detecting the positional relationship between the head and the plurality of tracks in the track width direction is recorded, and a plurality of the separation patterns of each track are not reproduced simultaneously by the reproduction head during reproduction. In the method of reproducing a recording medium arranged by shifting the section in the direction in which the track travels, at least in the reproduction signal of the reproduction head in the section in which the separation pattern for the unit is arranged The reproduction signal corresponding to the section of the separation pattern that is not reproduced by the head is set to a predetermined value. Instead it came, and has 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, in the reproduction signal of the reproduction head in the section where the separation pattern for the unit is arranged, at least the reproduction signal corresponding to the section of the separation pattern not reproduced by the reproduction head is replaced with a predetermined value. By performing the channel estimation calculation, it is possible to reduce the influence on the channel estimation calculation due to noise included in the reproduced signal in the section of the separation pattern for the unit. As a result, it is possible to satisfactorily perform signal separation arithmetic processing and realize high track density.

  A track format based on another aspect of the present invention is a track format that can be reproduced by the reproduction apparatus of the present invention, and has a plurality of tracks that constitute a unit that is a unit of signal processing for data reproduction. In each of the plurality of tracks, data and a preamble including a separation pattern necessary for detecting a positional relationship between the reproduction head at the time of reproduction and the plurality of tracks in the track width direction are arranged. Are separated from each other in the advancing direction of the track so that a plurality of the separation patterns are not simultaneously reproduced by the reproduction head during reproduction, and the separation pattern of at least one track is included in the preamble of another track. Arranged at a position that overlaps the pattern in the traveling direction of the track. Characterized in that it is. Here, the pattern in the preamble of the other track may be a pattern for gain control with respect to the reproduction signal or a pattern for synchronization detection.

  Furthermore, a track format based on another aspect of the present invention is a track format that can be played back by the playback device of the present invention, and includes a plurality of tracks constituting a unit that is a unit of signal processing for data playback. Each of the plurality of tracks is arranged with data and a preamble including a separation pattern necessary for detecting a positional relationship between the reproduction head at the time of reproduction and the plurality of tracks in the track width direction, and The separation patterns of each track are arranged with a section being shifted in the traveling direction of the track so that a plurality of the separation patterns are not simultaneously reproduced by the reproducing head during reproduction, and the separation pattern of the plurality of tracks is arranged in the traveling direction of the track. They are arranged in the same section.

  A recording medium according to another aspect of the present invention is a recording medium that can be reproduced by the reproducing apparatus of the present invention, and has a plurality of tracks constituting a unit that is a unit of signal processing for data reproduction. Each of the plurality of tracks is recorded with data and a preamble including a separation pattern necessary for detecting a positional relationship between the reproducing head at the time of reproduction and the plurality of tracks in the track width direction. The separation patterns are recorded by shifting the sections in the traveling direction of the track so that a plurality of separation patterns are not simultaneously reproduced by the reproduction head during reproduction, and the separation pattern of at least one track is recorded in the preamble of another track. It is recorded at a position overlapping with the pattern in the traveling direction of the track. That. Here, the pattern in the preamble of the other track may be a pattern for gain control with respect to the reproduction signal or a pattern for synchronization detection.

  A recording medium based on still another aspect of the present invention is a recording medium that can be reproduced by the reproducing apparatus of the present invention, and has a plurality of tracks constituting a unit that is a unit of signal processing for data reproduction. In each of the plurality of tracks, data and a preamble including a separation pattern necessary for detecting a positional relationship between the reproducing head and the plurality of tracks in the track width direction during recording are recorded. The separation patterns of the tracks are recorded by shifting the sections in the traveling direction of the tracks so that a plurality of the separation patterns are not simultaneously reproduced by the reproducing head during reproduction, and the separation patterns of the plurality of tracks are the same in the traveling direction of the tracks. It is recorded in the section.

  According to still another aspect of the present invention, a recording / reproducing apparatus includes: a reproducing apparatus having a reproducing head; and signal processing for data reproduction by a recording head on a recording medium so that data can be reproduced by the reproducing apparatus. A multi-track recording / encoding unit for encoding data to be recorded for each track. And detecting the positional relationship in the track width direction during reproduction between the reproduction head and the plurality of tracks in the code string of the data for each track encoded by the multi-track recording encoding unit. A multi-track preamble adding unit for adding a preamble including a necessary separation pattern; and the preambles of the plurality of tracks. And the data for each track to which the preamble has been added by the multi-track preamble adding unit so that the data and the data are arranged as a unit that is a unit of signal processing for reproducing the data. A multi-track recording unit for recording on the recording medium, wherein the reproducing apparatus is not reproduced at least by the reproducing head in a reproduction signal of the reproducing head in a section where the separation pattern for the unit is arranged. 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 by replacing the reproduction signal corresponding to the section of the separation pattern with a predetermined value It comprises.

  According to the present invention, in the reproduction apparatus, the reproduction signal corresponding to at least the section of the separation pattern that is not reproduced by the reproduction head can be determined in advance in the reproduction signal of the reproduction head in the section where the separation pattern for the unit is arranged. By performing the channel estimation calculation by substituting the values, it is possible to reduce the influence on the channel estimation calculation due to noise included in the reproduction signal in the section of the separation pattern for the unit. As a result, it is possible to satisfactorily perform signal separation arithmetic processing and realize high track density.

  According to the present invention, the influence of noise included in a reproduction signal on channel estimation calculation can be reduced, signal separation calculation processing can be performed satisfactorily, and the quality of reproduction 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 = 4 and N = 4.

  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 records data 1 for the number of recording heads W-1, W-2, W-3, and W-4 (M = 4) provided in the recording head array 150 for multitracking. The data distributor 111 distributes the data.

  The multi-track recording encoding unit 120 includes M recording encoding units 121-1, 121-2, 121-3, and 121-4 that encode the recording data allocated to M by the data distributor 111. Composed.

  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, 131-4.

  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, 141-4, M recording compensation units 144-1, 144-2, 144-3, 144-4 for performing recording compensation processing, and recording M recording amplifiers 147-1, 147-2, 147-3 for driving the individual recording heads W-1, W-2, W-3, W-4 based on the recording code string after the compensation processing, 147-4.

  The recording head array 150 has M recording heads W-1, W-2, W-3, and W-4 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 converted into data of the number of recording heads W-1, W-2, W-3, W-4 (M = 4) by the multitracking unit 110, That is, the data is distributed to the number of tracks constituting the unit (step S101).

  Each distributed data is encoded by the recording encoding units 121-1, 121-2, 121-3, 121-4 of the multitrack recording encoding unit 120 in consideration of the recording / reproducing characteristics of the magnetic recording medium 2. Encoded into a column. 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 recording and encoding units 121-1, 121-2, 121-3, and 121-4 are performed by the independent preamble adding units 131-1, 131-2, 131-3, and 131-4 of the multi-track preamble adding unit 130. A preamble necessary for data reproduction control is added to each recording data encoded by the above-described method, 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, 121-3, 121-4 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, 141-3, and 141-4 of the multitrack recording unit 140, and then the recording compensation unit 144- In 1, 144-2, 144-3, 144-4, a recording compensation process for optimizing the recording on the magnetic recording medium 2 is performed. The recording code string for each track subjected to the recording compensation processing is converted from voltage to current by the recording amplifiers 147-1, 147-2, 147-3, 147-4, and the recording heads W-1, W-2, W-3 and W-4 are sent to the magnetic recording medium 2 by the recording heads W-1, W-2, W-3 and W-4 (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 = 4) reproducing heads R-1, R-2, R-3, and R-4 that read signals from the tracks recorded on the magnetic recording medium 2. Each reproducing head R-1, R-2, R-3, R-4 has its head width and arrangement so that signals can be reproduced from one or more adjacent tracks on the magnetic recording medium 2. Is decided.

  The channel reproducing unit 220 amplifies the signals reproduced by the N reproducing heads R-1, R-2, R-3, and R-4 mounted on the reproducing head array 210, and N reproducing amplifiers 221-1. , 221-2, 221-3, 221-4 and the N reproduction amplifiers 221-1, 221-2, 221-3, and 221-4 are controlled in gain so that the amplitude levels of the outputs become predetermined values. The output of the gain adjusting units 224-1, 224-2, 224-3, and 224-4 and the gain adjusting units 224-1, 244-2, 224-3, and 224-4 are converted into digital values having a predetermined bit width. A / D converters 225-1, 225-2, 225-3, and 225-4 for quantization are provided.

  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, 225-3, and 225-4 as necessary.

  Further, the gain adjusting units 224-1, 224-2, 224-3, and 224-4 are arranged not in the preceding stage of the A / D converters 225-1, 225-2, 225-3, and 225-4 but in the subsequent stage. Also good. This is because the bit widths of the A / D converters 225-1, 225-2, 225-3, and 225-4 are used more effectively, or the gain adjusting units 224-1, 224-2, 224-3, and 224-4 are used. This configuration is effective when it is desired to simplify the configuration considering the detection of each pattern included in the preampule.

  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 separation pattern partial processing control unit 238, a channel estimation calculation unit 234, a reproduction position control processing unit 235, and a signal. A separation calculation unit 236 is provided.

  The synchronization signal detection unit 231 reproduces the reproduction heads R-1, R-2, R-3, and R-4 output from the A / D converters 225-1, 225-2, 225-3, and 225-4. A synchronization pattern in the preamble is detected from the signal.

  The identification information detection unit 232 is based on the synchronization pattern detected by the synchronization signal detection unit 231 and the position of the identification pattern in the reproduction signal of each reproduction head R-1, R-2, R-3, R-4. And identification information of the track is obtained by detecting this identification pattern.

  The reproduction signal gain control processing unit 233 detects the gain control pattern in the preamble from the reproduction signals of the respective reproduction heads R-1, R-2, R-3, R-4 that have passed through the synchronization signal detection unit 231, and Based on the signal of this gain control pattern, the gain for the reproduction signal of each reproduction head R-1, R-2, R-3, R-4 is calculated, and each reproduction head R-1, R-2, Controls the level of the reproduction signal of R-3 and R-4.

  Based on the track identification information detected by the identification information detection unit 232, the separation pattern partial processing control unit 238 performs individual reproduction heads R-1, R-2,. For each of the reproduction signals R-3 and R-4, a reproduction signal corresponding to a separation pattern section reproduced by the reproduction head and a reproduction signal corresponding to a separation pattern section not reproduced by the reproduction head are discriminated. Then, the reproduction signal corresponding to the section of the separation pattern reproduced by the reproduction head is used as it is, and the reproduction signal corresponding to the section of the separation pattern not reproduced by the reproduction head is replaced with a predetermined value to perform channel estimation calculation. Thus, necessary information is output to the channel estimation calculation unit 234.

  Based on the synchronization pattern detected by the synchronization signal detector 231 and the identification information obtained by the identification information detection unit 232, the channel estimation calculation unit 234 performs reproduction heads R-1, R-2, R-3. , R-4, the head position of the separation pattern included in the preamble of the reproduction signal, and using the reproduction signal of the separation pattern portion and information from the separation pattern portion processing control unit 238, the reproduction heads R-1, Channel estimation calculation is performed to calculate a channel matrix corresponding to the positional relationship in the track width direction during reproduction of R-2, R-3, R-4 and a plurality of tracks.

  The reproduction position control processing unit 235 is based on the synchronization pattern detected by the synchronization signal detection unit 231 and each reproduction head R-1, R-2, R-3, R that has passed through the reproduction signal gain control processing unit 233. -4 is performed to match the reproduction position of the reproduction signal.

  The signal separation calculation unit 236 is obtained by the channel estimation calculation unit 234 from the reproduction signals of the respective reproduction heads R-1, R-2, R-3, and R-4 whose reproduction positions are aligned by the reproduction position control processing unit 235. Using the obtained channel matrix, a process for separating the reproduction signal for each track is performed 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, 241-4, and M PLLs 242-1, 242-2, 242-3 that perform bit synchronization from the outputs of the equalizers 241-1, 241-2, 241-3, and 241-4. 242-4 and the bit synchronization signal generated by PLLs 242-1, 242-2, 242-2, and 242-4 to generate a code string by binarizing the reproduction signal of each track, for example, a Viterbi detector The binarized reproduction that is the output of the M detectors 243-1, 243-2, 243-3, 243-4 and the detectors 243-1, 243-2, 243-3, 243-4 Detect synchronization pattern on code sequence from signal Synchronization patterns detected by the M synchronization signal detectors 244-1, 244-2, 244-3, 244-4 and the synchronization signal detectors 244-1, 244-2, 244-3, 244-4 M decoders 245-1, 245-2, 245-3, and 245-4 that specify the head position of the data and decode the data sequence from the code string. 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 records the data of each track output from the M decoders 245-1, 245-2, 245-3 and 245-4 in the multi-track demodulation unit 240 at the time of recording. And a data combiner 261 that restores the reproduced data 3 by connecting them in the reverse operation.

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

  In the reproducing apparatus 200, first, the magnetic recording medium 2 is formed by N reproducing heads R-1, R-2, R-3, and R-4, each of which can reproduce a signal from one or more adjacent tracks. A signal is reproduced from a plurality of tracks of one unit (step S201).

  Next, the gain adjustment units 224-1, 224-2, 224-3, and 224-4 adjust the amplitude levels of the outputs of the reproduction amplifiers 221-1, 221-2, 221-3, and 221-4. After that, the outputs of the gain adjusting units 224-1, 224-2, 224-3 and 224-4 are converted into digital values by the A / D converters 225-1, 225-2, 225-3 and 225-4. Is output to the synchronization signal detector 231 (step S202).

  Next, the reproducing heads R-1, R-2, R-3, R output from the A / D converters 225-1, 225-2, 225-3, 225-4 by the synchronization signal detector 231. Synchronization patterns are detected from the reproduction signals for every -4 (step S203).

  Next, the identification information detection unit 232 identifies the reproduction signals of the reproduction heads R-1, R-2, R-3, and R-4 based on the synchronization pattern detected by the synchronization signal detection unit 231. The head position of the pattern is specified to detect the identification pattern, and identification information is obtained (step S204).

  Subsequently, the reproduction signal gain control processing unit 233 obtains a gain control pattern in the preamble from the reproduction signals of the reproduction heads R-1, R-2, R-3, and R-4 that have passed through the synchronization signal detector 231. Based on this gain control pattern, the gains for the reproduction signals of the reproducing heads R-1, R-2, R-3, and R-4 are calculated, and the reproducing heads R-1, R-2 are calculated. , R-3 and R-4 are individually controlled (step S205).

  Next, based on the track identification information detected by the identification information detection unit 232 in the separation pattern partial processing control unit 238, each reproducing head R-1, For each reproduction signal of R-2, R-3, R-4, a reproduction signal corresponding to a section of a separation pattern reproduced by the reproduction head and a reproduction signal corresponding to a section of a separation pattern not reproduced by the reproduction head And the reproduction signal corresponding to the section of the separation pattern reproduced by the reproduction head is used as it is, and the reproduction signal corresponding to the section of the separation pattern not reproduced by the reproduction head is replaced with a predetermined value and the channel is used. Necessary information is output to the channel estimation calculation unit 234 so as to perform the estimation calculation (step S206).

  Next, based on the synchronization pattern detected by the synchronization signal detector 231 and the identification information obtained 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, R-4, the start position of the separation pattern included in the preamble of the reproduction signal, and a predetermined signal using the reproduction signal of the separation pattern portion and information from the separation pattern portion processing control unit 238 A channel matrix is obtained by channel estimation calculation (step S207). This channel matrix is the position information in the track width direction of the individual reproducing heads R-1, R-2, R-3, R-4 for each track # 1, # 2, # 3, # 4 in one unit. In other words, it is information that indicates at what ratio and in what proportion each reproducing head R-1, R-2, R-3, R-4 each position in the unit. is there.

  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. Processing for adjusting the reproduction positions of the reproduction signals of −3 and R-4 is performed (step S208).

  Next, in the signal separation calculation unit 236, channel estimation calculation is performed from the reproduction signals of the reproduction heads R-1, R-2, R-3, and R-4 whose reproduction positions are aligned by the reproduction position control processing unit 235. Using the channel matrix obtained by the unit 234, processing for separating the reproduction signal for each track is performed (step S209).

  Thereafter, the multi-track demodulation unit 240 decodes the data sequence from the reproduction signal for each track (step S210), and the restoration unit 260 concatenates the data of each track to obtain reproduction data 3 (step S210). S211).

  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, track # 3, and track # 4 are tracks recorded on the magnetic recording medium 2 by M (M = 4) recording heads of the recording apparatus 100, respectively. Preamble 21 and data 22 are recorded in track # 1, track # 2, track # 3, and track # 4, 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 group of M preambles 21 and M data 22 in each of M tracks # 1, # 2, # 3, and # 4 is a unit of signal processing for reproducing data. As a unit 51.

  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 a gain control pattern 41-1, 41-2, 41-3, 41-4, a synchronization pattern 42-1, 42-2, 42-3, 42-4, an identification pattern 43-1, 43-2, 43-3, 43-4, gain control patterns 41-1, 41-2, 41-3, 41-4 and synchronization patterns 42-1, 42-2, 42-3, 42-. 4 and the identification patterns 43-1, 43-2, 43-3, 43-4 are continuously arranged. The second preamble 24 is composed of separation patterns 44-1, 44-2, 44-3, 44-4. 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. Are arranged in the order of the separation pattern 44-3. On the track # 4, the gain control pattern 41-4, the synchronization pattern 42-4, the identification pattern 43-4, and the separation pattern 44-4 are arranged in this order from the top. Data 22 is arranged after the separation patterns 44-1, 44-2, 44-3, and 44-4. The data 22 is a recording code string created by the recording encoding units 121-1, 121-2, 121-3, and 121-4 of the recording apparatus 100 in 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, 131-3, and 131-4.

  In the example of FIG. 7, the widths of the reproducing heads R-1, R-2, R-3, and R-4 are 1.5 times the track width. That is, the width of the reproducing heads R-1, R-2, R-3, R-4 is 1.5 times the head width of the recording heads W-1, W-2, W-3, W-4, for example. Each of the reproducing heads R-1, R-2, R-3, and R-4 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 three tracks # 2, # 3, and # 4, and the reproducing head R-4 reproduces a signal across the track # 3 and the track # 4. .

  In the first preamble 23, the gain control patterns 41-1, 41-2, 41-3, 41-4 of the tracks # 1, # 2, # 3, and # 4, the synchronization patterns 42-1, 42-2, 42-3, 42-4 and the identification patterns 43-1, 43-2, 43-3, 43-4 are arranged so that their positions in the direction in which the tracks proceed 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 Ta section, the gain control pattern 41-2 of the track # 2, the synchronization pattern 42-2 and The identification pattern 43-2 is in the Tb section, the gain control pattern 41-3 of the track # 3, the synchronization pattern 42-3, and the identification pattern 43-3 is in the Tc section, the gain control pattern 41-4 of the track # 4, and the synchronization pattern. 42-4 and the identification pattern 43-4 are arranged in the Td section. And adjacent track gain control patterns 41-1, 41-2, 41-3, 41-4, synchronization patterns 42-1, 42-2, 42-3, 42-4, and identification patterns 43-1, 43. A gap 28 for a margin is provided between the recording sections of −2, 43-3, and 43-4.

  At the time of reproduction, the gain control patterns 41-1, 41-2, 41-3, and 41-4 of the tracks # 1, # 2, # 3, and # 4 are stored 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, 221-3, and 221-4 by the gain adjusting units 224-1, 224-2, 224-3, and 224-4. The gain control patterns 41-1, 41-2, 41-3, and 41-4 are used for learning for bit synchronization detection by the synchronization signal detector 231 and a reproduction signal gain control processing unit 233 as necessary. It is also used to control the level of each reproduction signal. Furthermore, the gain control patterns 41-1, 41-2, 41-3, and 41-4 are used for reproduction position control of each reproduction signal by the reproduction position control processing unit 235 as necessary.

  At the time of reproduction, the synchronization patterns 42-1, 42-2, 42-3, and 42-4 of the tracks # 1, # 2, # 3, and # 4 are detected by the synchronization signal detector 231, for example, Identification patterns 43-1, 43-2, 43-3, 43-4 for tracks # 1, # 2, # 3, and # 4, and separation patterns 44- for tracks # 1, # 2, # 3, and # 4 1, 44-2, 44-3, 44-4 and information 22 are used as information for knowing the head position of the data 22. Further, the synchronization patterns 42-1, 42-2, 42-3, and 42-4 are used for reproduction position control of each reproduction signal in the reproduction position control processing unit 235.

  In addition, the identification patterns 43-1, 43-2, 43-3, and 43-4 of the tracks # 1, # 2, # 3, and # 4 at the time of reproduction are the synchronization patterns detected by the synchronization signal detector 231. 42-1, 42-2, 42-3, and 42-4 are detected by the identification information detection unit 232 and used to obtain track identification information, and the channel estimation calculation unit 234 performs channel estimation calculation. Used for. The identification information is used for playback position control in the playback position control processing unit 235. Further, the identification information is used for processing the reproduction signal of the separation pattern portion in the separation pattern portion processing control unit 238.

  In this track format, in the first preamble 23, gain control patterns 41-1, 41-2, 41-3, 41-4 and synchronization pattern 42-1 of each track # 1, # 2, # 3, # 4 are provided. , 42-2, 42-3, 42-4 and the identification patterns 43-1, 43-2, 43-3, 43-4 are arranged so that their positions in the direction in which the tracks proceed do not overlap each other. Therefore, even when the channel clock positions of the tracks # 1, # 2, # 3, and # 4 are not aligned, a plurality of individual reproducing heads R-1, R-2, R-3, and R-4 are provided. When a signal is reproduced across two tracks, the output of the reproduction signal does not decrease due to cancellation by the recording signal of each track. Thereby, gain control patterns 41-1, 41-2, 41-3, 41-4, synchronization patterns 42-1, 42-2, 42-3, 42-4, identification patterns 43-1, 43-2, Said control using 43-3, 43-4 can be performed favorably.

  On the other hand, in the second preamble 24, the separation patterns 44-1, 44-2, 44-3, and 44-4 of the tracks # 1, # 2, # 3, and # 4 are reproduced by the reproducing head R-1 during reproduction. , R-2, R-3, R-4, a channel matrix required for calculation for separating the reproduction signals for tracks # 1, # 2, # 3, and # 4 from the reproduction signals is calculated by a channel estimation calculation unit 234. This is the pattern used to find out.

  These separation patterns 44-1, 44-2, 44-3, and 44-4 are also arranged so that the positions in the track traveling direction do not overlap each other. That is, in FIG. 7, the separation pattern 44-1 for track # 1 is in the T1 section, the separation pattern 44-2 for track # 2 is in the T2 section, and the separation pattern 44-3 for track # 3 is in the T3 section. The four separation patterns 44-4 are recorded in the T4 section. As a result, there are four types of separation patterns corresponding to the number of tracks. A gap 29 for a predetermined time for a margin is provided between the recording sections of the separation patterns 44-1, 44-2, 44-3, and 44-4 of adjacent tracks.

  Here, the separation patterns 44-1, 44-2, 44-3, and 44-4 are recorded at a predetermined recording wavelength equal to or greater than the minimum recording wavelength.

  Next, returning to FIG. 6, the identification patterns 43-1, 43-2, 43-3, 43-4 arranged in the first preamble 23 of each track # 1, # 2, # 3, # 4 are returned. Details 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)

  In the identification information detection unit 232, the reproducing heads R-1, R-2, R- based on the synchronization patterns 42-1, 42-2, 42-3, 42-4 detected by the synchronization signal detection unit 231. 3 and the leading position of the identification pattern 43-1, 43-2, 43-3, 43-4 in the reproduction signal for each R-4 is specified, and the identification pattern 43-1, 43-2, 43-3, 43 is identified. -4 is 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 outputs the reproduction signals of the gain control patterns 41-1, 41-2, 41-3, and 41-4 for each of the reproduction heads R-1, R-2, R-3, and R-4. Based on, for example, the gain of the reproduction signal for each of the reproduction heads R-1, R-2, R-3, and R-4 is calculated as follows, 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 performs gain control pattern 41-2, gain control pattern 41-3, and gain control reproduced from the track # 2, track # 3, and track # 4 by the reproduction head R-3. The signals of the pattern 41-4 are added. Similarly, the reproduction signal gain control processing unit 233 adds the signals of the gain control pattern 41-3 and the gain control pattern 41-4 reproduced from the track # 3 and the track # 4 by the reproduction head R-4.

  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 selects this one from all the reproduction heads R-1, R-2, R-3, R-. 4 as a reference output. 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.

  (Separation pattern partial process control unit 238)

  The separation pattern partial processing control unit 238, for example, based on the identification information obtained by the identification information detection unit 232, the individual reproducing heads R-1 and R-2 in the section in which the separation patterns for the units are arranged. , R-3, R-4, a reproduction signal corresponding to a section of a separation pattern reproduced by the reproduction head and a reproduction signal corresponding to a section of a separation pattern not reproduced by the reproduction head, respectively. Discriminating and using the reproduced signal corresponding to the section of the separation pattern reproduced by the reproducing head as it is, and replacing the reproduced signal corresponding to the section of the separating pattern not reproduced by the reproducing head with a predetermined value to perform channel estimation calculation Necessary information is output to the channel estimation calculation unit 234 so as to be performed.

  Next, the process of the separation pattern partial process control unit 238 when the track format of FIG. 7 is used will be described in detail.

  In FIG. 7, the head widths of the reproducing heads R-1, R-2, R-3, and R-4 are 1.5 times the recording track width, and the individual reproducing heads R-1, R-2, A plurality of tracks can be reproduced by R-3 and R-4. 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 three tracks # 2, # 3, and # 4, and the reproducing head R-4 reproduces the signal across the track # 3 and the track # 4. To do.

  FIG. 8 is a diagram showing a reproduction signal for the track format of FIG. Here, when there is no off-track, that is, the centers of the reproducing heads R-1, R-2, R-3, and R-4 coincide with the centers of the tracks # 1, # 2, # 3, and # 4, respectively. The reproduction signals of the reproducing heads R-1, R-2, R-3, and R-4 are shown in the case of In FIG. 7, 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 the example of FIG. 8, 20 data is allocated to each track as the first preamble 23, and 40 data is allocated to each track as the second preamble 24, and a gap of 10 data is provided between them. It has been. At this time, the reproduction signal portion used in the channel estimation calculation unit 234 includes 20 data in the separation pattern section (T1 section) of track # 1, and 20 data in the separation pattern section (T2 section) of track # 2. 20 data of the separation pattern section (T3 section) of track # 3 and 20 data of the separation pattern section (T4 section) of track # 4.

  8, in an ideal state, in the separation pattern section (T1 section) of track # 1, the output value of the reproduction signal 1-1 by the reproduction head R-1 and the reproduction signal 2-1 by the reproduction head R-2. The output value of the reproduction signal 3-1 from the reproduction head R-3 and the output value of the reproduction signal 4-1 from the reproduction head R-4 are both zero.

  Similarly, in an ideal state, in the separation pattern section (T2 section) of track # 2, the output value of the reproduction signal 1-2 by the reproduction head R-1 and the output value of the reproduction signal 2-2 by the reproduction head R-2. The value and the output value of the reproduction signal 3-2 from the reproduction head R-3 are significant values, while the output value of the reproduction signal 4-2 from the reproduction head R-4 is zero.

  Similarly, in an ideal state, in the separation pattern section (T3 section) of the track # 3, the output value of the reproduction signal 2-3 by the reproduction head R-2 and the output of the reproduction signal 3-3 by the reproduction head R-3. While the value and the output value of the reproduction signal 4-3 from the reproduction head R-4 are significant, the output value of the reproduction signal 1-3 from the reproduction head R-1 is zero.

  Similarly, in an ideal state, the output value of the reproduction signal 3-4 from the reproduction head R-3 and the reproduction signal 4-4 from the reproduction head R-4 in the separation pattern section (T4 section) of the track # 4. While each of the output values is a significant value, the output value of the reproduction signal 1-4 from the reproduction head R-1 and the output value of the reproduction signal 2-4 from the reproduction head R-2 are both zero.

  However, the quality of the reproduction signal actually obtained from the data recording medium is often deteriorated due to media noise or disturbance, and is not necessarily in the ideal state described above. That is, the output values of the reproduction signal 3-1, the reproduction signal 4-1, the reproduction signal 4-2, the reproduction signal 1-3, the reproduction signal 1-4, and the reproduction signal 2-4 are not necessarily zero.

  Therefore, in the present embodiment, the separation pattern partial processing control unit 238 performs the reproduction signals 1-1 to 4-4 shown in FIG. 8 based on the identification information obtained by the identification information detection unit 232, for example. Then, it discriminates what should be used as it is for the channel estimation calculation and what should be used for the channel estimation calculation by replacing it with another predetermined value, and outputs this result to the channel estimation calculation unit 234. When the above determination is made based on the identification information, the reproduction signal of the separation pattern portion of the track from which the identification information is obtained is directly used for the channel estimation calculation, and the reproduction signal of the separation pattern portion of the track from which the identification information is not obtained. Is replaced with another predetermined value for use in the channel estimation calculation. Here, as the other predetermined value, a value that does not affect the channel estimation calculation, for example, zero is used.

  That is, in the example of FIG. 8, since the identification information of the track # 1 and the track # 2 is obtained by the identification information detection unit 232 in the reproduction signal # 1 from the reproduction head R-1, the separation pattern partial processing control unit 238 The channel estimation calculation is performed on the reproduction signal 1-1 corresponding to the separation pattern section (T1 section) of the track # 1 and the reproduction signal 1-2 having a small output corresponding to the separation pattern section (T2 section) of the track # 2. And the reproduction signal 1-3 corresponding to the separation pattern section (T3 section) of the track # 3 and the reproduction signal 1-4 corresponding to the separation pattern section (T4 section) of the track # 4 are set to other predetermined values. Information is output to the channel estimation calculation unit 234 so as to be used for channel estimation calculation.

  In addition, since the identification information of the tracks # 1, # 2, and # 3 is obtained by the identification information detection unit 232 in the reproduction signal # 2 from the reproduction head R-2, the separation pattern partial processing control unit 238 performs the reproduction head R. -2 is a reproduction signal 2-1 having a small output corresponding to the separation pattern section (T1 section) of the track # 1, and a reproduction signal 2 corresponding to the separation pattern section (T2 section) of the track # 2. -2 and the reproduced signal 2-3 having a small output corresponding to the separation pattern section (T3 section) of the track # 3 are used as they are for the channel estimation calculation, and correspond to the separation pattern section (T4 section) of the track # 4. Information is output to channel estimation calculation section 234 so that reproduced signal 2-4 is replaced with another predetermined value and used for channel estimation calculation.

  Further, since the identification information of the tracks # 2, # 3, and # 4 is obtained by the identification information detection unit 232 in the reproduction signal # 3 from the reproduction head R-3, the separation pattern partial processing control unit 238 performs the track # 2 Reproduction signal 3-2 having a small output corresponding to the separation pattern section (T2 section), reproduction signal 3-3 corresponding to the separation pattern section (T3 section) of track # 3, and separation pattern section ( The reproduction signal 3-4 having a small output corresponding to (T4 section) is directly used for channel estimation calculation, and the reproduction signal 3-1 corresponding to the separation pattern section (T1 section) of track # 1 is set to another predetermined value. Information is output to the channel estimation calculation unit 234 to be used for channel estimation calculation instead.

  Then, in the reproduction signal # 4 from the reproduction head R-4, since the identification information detection unit 232 has obtained the identification information of the track # 3 and the track # 4, the separation pattern partial processing control unit 238 performs the separation of the track # 3. The reproduction signal 4-3 having a small output corresponding to the pattern interval (T3 interval) and the reproduction signal 4-4 corresponding to the separation pattern interval (T4 interval) of the track # 4 are used as they are for the channel estimation calculation, and the track # Channel estimation is performed by replacing the reproduction signal 4-1 corresponding to one separation pattern interval (T1 interval) and the reproduction signal 4-2 corresponding to the separation pattern interval (T2 interval) of track # 2 with other predetermined values. Information is output to the channel estimation calculation unit 234 for use in the calculation.

  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 reproduces the read heads R-1, R-2, R-3. , R-4, the start position of the reproduction signal of the separation pattern portion in the reproduction signal is specified, and based on the information given from the separation pattern partial processing control unit 238, the output values of some reproduction signals are changed to other values. The channel estimation calculation is performed by replacing with a predetermined value, and a channel matrix necessary for signal separation processing is generated.

  In this embodiment, the reproduction signal of the separation pattern section of the track for which identification information is obtained is used as it is for the channel estimation calculation, and the reproduction signal of the separation pattern section of the track for which identification information is not obtained is set to another predetermined value. However, the reproduced signal in the separation pattern section of the track separated by a predetermined number of tracks from the track for which the identification information is obtained may be replaced with another predetermined value. Good. Alternatively, the reproduction signal of the separation pattern section of the track to be replaced with a predetermined value may be determined in consideration of the output size of the detected identification pattern.

  As described above, according to the present embodiment, in the reproduction signal of the reproduction head in the section in which the separation patterns for the units are arranged, at least the reproduction signal corresponding to the section of the separation pattern that is not reproduced by the reproduction head is previously stored. By performing the channel estimation calculation by substituting the determined value, it is possible to reduce the influence on the channel estimation calculation due to noise included in the reproduction signal in the section of the separation pattern for the unit. As a result, it is possible to satisfactorily perform signal separation arithmetic processing and realize high track density.

  Next, a modification of the above embodiment will be shown.

FIG. 9 is a diagram showing a modification of the track format shown in FIG.
In this track format, the separation pattern 44-1 of the track # 1 and the first preamble 23 of the track # 4 are arranged at positions that overlap each other in the track traveling direction.

  Normally, in such a format configuration, the reproduction signal for the pattern of the first preamble 23 of track # 4 becomes a noise component in the channel estimation calculation, and it is difficult to perform the channel estimation calculation well. By replacing the output value of the reproduction signal with respect to the pattern of the first preamble 23 of the track # 4 with a predetermined value such as zero, the channel estimation calculation is performed, so that the reproduction signal of the first preamble 23 of the track # 4 is It is possible to reduce the influence as a noise component in the estimation calculation, and it is possible to perform the channel estimation calculation satisfactorily.

  FIG. 10 is a diagram showing another modification of the track format of FIG. In this track format, the configuration of the second preamble 24 is different from the track format shown in FIG. 7, and the separation pattern 44-1 of track # 1 and the separation pattern 44-4 of track # 4 are different from each other. It arrange | positions in the same position (T1 area) in the advancing direction.

  At this time, there are three types of separation patterns which are smaller than the number of tracks.

  In the track format of FIG. 10, the head widths of the reproducing heads R-1, R-2, R-3, and R-4 are 1.5 times the recording track width. Signals from a plurality of tracks are reproduced by R-2, R-3, and R-4. 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 three tracks # 2, # 3, and # 4, and the reproducing head R-4 reproduces the signal across the track # 3 and the track # 4. To do.

  FIG. 11 is a diagram showing a reproduction signal for the track format of FIG. Here, when there is no off-track, that is, the centers of the reproducing heads R-1, R-2, R-3, and R-4 coincide with the centers of the tracks # 1, # 2, # 3, and # 4, respectively. The reproduction signals of the reproducing heads R-1, R-2, R-3, and R-4 are shown in the case of In FIG. 11, 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 the example of FIG. 11, 20 data is allocated to each track as the first preamble 23, and 40 data is allocated to each track as the second preamble 24, and a gap of 10 data is provided between them. It has been. At this time, the reproduction signal portion used in the channel estimation calculation unit 234 includes 20 data in the separation pattern section (T1 section) of track # 1, and 20 data in the separation pattern section (T2 section) of track # 2. 20 data in the separation pattern section (T3 section) of track # 3 and 20 data in the separation pattern section (T1 section) of track # 4.

  In this track format, since the separation patterns of track # 1 and track # 4 are both arranged in the T1 interval, the separation pattern partial processing control unit 238 outputs the reproduction signal of the separation pattern in the T1 interval in the T1 interval. Information is output to the channel estimation calculation unit 234 so that the channel estimation calculation is performed a plurality of times (twice) as the reproduction signal of the virtual T4 section.

  Specifically, first, the separation pattern partial processing control unit 238 includes the reproduction signal 1-1 corresponding to the separation pattern section (T1 section) of the track # 1 and the track in the reproduction signal # 1 from the reproduction head R-1. The reproduced signal 1-2 having a small output corresponding to the separation pattern section (T2 section) of # 2 is used as it is for the channel estimation calculation, and the reproduced signal 1-3 corresponding to the separation pattern section (T3 section) of the track # 3 is used. Is replaced with another predetermined value such as zero, and the information is output to the channel estimation calculation unit 234 so that it is used for the channel estimation calculation. Also, the separation pattern partial processing control unit 238 replaces the reproduction signal 1-1 for the separation pattern of the track # 1 in the reproduction signal # 1 of the T1 section with a predetermined value, for example, zero, for the T4 section shown in FIG. The information is output to the channel estimation calculation unit 234 so as to be used as the reproduced signal 1-4.

  Next, the separation pattern partial processing control unit 238 generates a reproduction signal 2-1 having a small output corresponding to the separation pattern section (T1 section) of the track # 1 in the reproduction signal # 2 from the reproduction head R-2, and the track #. The reproduction signal 2-2 corresponding to two separation pattern sections (T2 section) and the reproduction signal 2-3 having a small output corresponding to the separation pattern section (T3 section) of track # 3 are used as they are for channel estimation calculation. As described above, information is output to the channel estimation calculation unit 234. Further, the separation pattern partial processing control unit 238 replaces the reproduction signal 2-1 for the separation pattern of the track # 2 in the reproduction signal # 2 of the T1 section with a predetermined value, for example, zero, for the T4 section shown in FIG. Information is output to the channel estimation calculation unit 234 so as to be used as the reproduced signal 2-4.

  Next, the separation pattern partial processing control unit 238 sets the reproduction signal 3-1 corresponding to the separation pattern section (T1 section) of the track # 1 to a predetermined value, for example, zero, in the reproduction signal # 3 by the reproduction head R-3. The replacement is used for channel estimation calculation, and corresponds to the reproduction signal 3-2 having a small output corresponding to the separation pattern section (T2 section) of track # 2 and the separation pattern section (T3 section) of track # 3. The information is output to the channel estimation calculation unit 234 so that the reproduced signal 3-3 to be used is directly used for the channel estimation calculation. Also, the separation pattern partial processing control unit 238 uses the reproduction signal 3-1 for the separation pattern of the track # 3 in the reproduction signal # 3 of the T1 section as it is as the reproduction signal 3-4 of the T4 section shown in FIG. As described above, information is output to the channel estimation calculation unit 234.

  The separation pattern partial processing control unit 238 then separates the reproduction signal 4-1 corresponding to the separation pattern section (T1 section) of the track # 1 and the separation pattern section of the track # 2 in the reproduction signal # 4 from the reproduction head R-4. A signal obtained by replacing the reproduction signal 4-2 corresponding to (T2 interval) with a predetermined value, for example, zero, is used for channel estimation calculation, and the reproduction signal 4 corresponding to the separation pattern interval (T3 interval) of track # 3 Information is output to the channel estimation calculation unit 234 so that -3 is used as it is for the channel estimation calculation. Also, the separation pattern partial processing control unit 238 uses the reproduction signal 4-1 for the separation pattern of the track # 4 in the reproduction signal # 4 in the T1 section as it is as the reproduction signal 4-4 in the T4 section shown in FIG. As described above, information is output to the channel estimation calculation unit 234.

  As described above, even when the track format shown in FIG. 10 is adopted, the channel estimation calculation can be performed satisfactorily.

  Note that the method of performing channel estimation calculation using the reproduction signal of the T1 section twice as described above is not limited to the track format shown in FIG. 10 and can be similarly applied to the track format shown in FIG. In this track format, the separation pattern 44-1 of the track # 1 and the separation pattern 44-4 of the track # 4 are arranged at the same position (T1 section) in the track traveling direction, and the track # 1 The gain control pattern 41-1, the synchronization pattern 42-1, and the identification pattern 43-1 and the gain control pattern 41-4, the synchronization pattern 42-4, and the identification pattern 43-4 of the track # 4 are in the direction in which the track proceeds. It is arranged at the same position (Ta section). Even when this track format is adopted, the channel estimation calculation can be performed in the same manner as described above after detecting the sync pattern of each track and detecting the identification information.

  By the way, the configuration of the preamble in the track format to which the present invention is applicable is not limited to the above.

  For example, an identification pattern is not necessarily required to obtain track identification information. For example, a plurality of types of patterns may be prepared for the synchronization pattern, identification information may be associated with each type of synchronization pattern, and detection of the synchronization pattern and acquisition of the identification information may be performed simultaneously. Further, the identification information may be obtained by the position of the pattern in the first preamble.

  Further, 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.

  Further, the process of selectively replacing the reproduction signal in the section where the separation pattern for the unit is arranged using the track identification information may be used for purposes other than the channel estimation calculation and the signal separation process. It doesn't matter.

  Furthermore, in the above-described embodiment, a case where a 4 × 4 matrix is calculated as channel estimation information has been described. However, signal separation processing is performed by obtaining a generalized inverse matrix of other square matrices. It is possible. Furthermore, a generalized inverse matrix may be obtained in the same manner for a matrix other than a square matrix.

  In this case, in order to obtain a generalized inverse matrix of the matrix, the type of separation pattern is made to correspond to the number of tracks.

  In addition, the separation patterns are primary independent patterns corresponding to the number of tracks. For example, when the number of recording heads is 3 and the number of reproducing heads is 4, that is, when the reproducing signal is 4 with respect to the recording track 3, at least three separation pattern portions are mutually connected. It should be a primary independent pattern.

  In the track format shown in FIGS. 10 and 12, the number of types of separation patterns is 3, which is smaller than 4 which is the number of tracks. However, since the reproduction signal in one separation pattern section is used twice, the separation pattern Since the number of processes in the portion is 4, it is considered that the condition is satisfied.

  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, the separation pattern orthogonal to the frequency axis or the orthogonal code is used. Alternatively, a separation pattern using 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.

  By the way, in the track format shown in FIGS. 10 and 12, a plurality of separation patterns in the same section are arranged two tracks apart so that a separation pattern of a plurality of tracks is not reproduced simultaneously by one reproducing head. However, for example, by providing a function to change the width of the reproducing head or to control the position of the reproducing head in the track width direction, it is possible to arrange a plurality of separation patterns in the same section separated by one track. It is.

  Next, an example of a track format in which the number of tracks to which the present invention can be applied is three will be shown.

  As shown in FIG. 13, in this track format, the first preamble 23 includes gain control patterns 41-1, 41-2, 41-3, synchronization patterns 42-1, 42-2, 42-3, and an identification pattern 43. -1, 43-2, 43-3. Reference numeral 41 denotes a range of gain control patterns 41-1, 41-2, and 41-3, reference numeral 42 denotes a range of synchronization patterns 42-1, 42-2, and 42-3, and reference numeral 43 denotes identification patterns 43-1 and 43-. 2, the first preamble 23 of each track # 1, # 2, # 3 is arranged at the same position in the track traveling direction.

  In this track 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 is obtained by omitting an identification pattern from the track format of FIG. As described above, even if the identification pattern is not included in the preamble, a unique pattern is adopted for the synchronization patterns 42-1, 42-2, and 42-3 for each track, or the positional relationship of the reproduction signals is grasped. The track can be identified.

  FIG. 15 shows an example in which the number of tracks is changed from 4 to 3 in the track format shown in FIG. The present invention can also be applied when such a track format is adopted.

  FIG. 29 shows the track format shown in FIG. 15 in which the separation patterns 44-1 and 44-3 of the track # 1 and the track # 3 are arranged at the same position in the track traveling direction. The present invention can also be applied when such a track format is adopted.

  FIG. 16 shows the track format shown in FIG. 29 in which the patterns of the first preambles 23 of the tracks # 1 and # 3 are arranged at the same position in the track traveling direction. The present invention can also be applied when such a track format is adopted.

  However, when the track formats of FIGS. 29 and 16 are adopted, in order to perform channel estimation calculation satisfactorily, a plurality of separation patterns arranged in the same section in the track traveling direction are simultaneously performed by one reproducing head. In order to prevent reproduction, it is necessary to select the width and position of the reproducing head and to control the position of the reproducing head during reproduction.

  In the above embodiment, the separation pattern partial processing control unit 238 determines the reproduction signal to be used as it is and the reproduction signal to be replaced with a predetermined value, and gives the information to the channel estimation calculation unit 234. The separation pattern partial processing control unit 238 may perform processing up to replacement of the reproduction signal, and output the result to the channel estimation calculation unit 234.

  (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. 17 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 multi-track recording encoding unit 120 includes M recording encoding units 121-1, 121-2, 121-3, and 121-4 that encode the recording data allocated to M by the data distributor 111. Composed.

  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, 131-4.

  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. 18 is a flowchart showing the flow of operation during unit recording of the recording apparatus 300.

  In this recording apparatus 300, first, the input recording data 1 is distributed to M (M = 4) pieces of data (data for each track) by the multitracking unit 110 (step S301).

  Each distributed data is encoded by the recording encoding units 121-1, 121-2, 121-3, 121-4 of the multitrack recording encoding unit 120 in consideration of the recording / reproducing characteristics of the magnetic recording medium 2. Encoded into a column. At this time, information necessary for data demodulation, such as a demodulation synchronization pattern, is also added to the code string (step S302).

  Next, the M independent preamble adding units 131-1, 131-2, 131-3, 131-4 of the multi-track preamble adding unit 130 are united at predetermined positions of each encoded recording data. A pattern necessary for reproduction control of unit data 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. 19 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. 17 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 of a predetermined unit, for example, recording data for a predetermined number of tracks, and the multitrack preamble adding unit 130 is configured for each track. The encoded recording data includes an independent preamble adding unit 131 that adds a preamble necessary for controlling data reproduction in units. 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. 20 is a flowchart showing the 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. Next, it moves to the position of track # 3 to record track # 3, and finally moves to the position of track # 4 to record track # 4.

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

  FIG. 21 is a diagram showing a configuration of a reproducing apparatus 400 in the magnetic recording / reproducing method 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 separation pattern partial processing control unit 238, a channel estimation calculation unit 234, a reproduction position control processing unit 235, a signal separation. A calculation unit 236 and a storage unit 237 are included.

  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.

  Based on the track identification information detected by the identification information detection unit 232, the separation pattern partial processing control unit 238 scans each reproduction signal of the reproduction head for each scan in the section where the separation patterns for the units are arranged. The playback signal corresponding to the section of the separation pattern that is sometimes played back is discriminated from the playback signal corresponding to the section of the separation pattern that is not played back during scanning, and the playback signal corresponding to the section of the separation pattern that is played back is used as it is. In addition, necessary information is output to the channel estimation calculation unit 234 so that the reproduction signal corresponding to the section of the separation pattern that is not reproduced is replaced with a predetermined value and the channel estimation calculation is performed.

  Based on the synchronization pattern detected by the synchronization signal detector 231 and the identification information obtained by the identification information detection unit 232, the channel estimation calculation unit 234 includes the preamble in the reproduction signal of the reproduction head R-1 for each scan. The head of the separation pattern included in the image is specified, and the reproduction head R-1 and a plurality of tracks are reproduced for each scan using the reproduction signal of this separation pattern portion and the information from the separation pattern portion processing control unit 238. A channel estimation calculation is performed to calculate a channel matrix corresponding to the positional relationship in the track width direction.

  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 uses the channel matrix obtained by the channel estimation calculation unit 234 to perform a process of separating the reproduction signal for each track from the reproduction signal for one unit input from the reproduction signal gain control processing unit 233. Do.

  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 241-2 that perform equalization processing on the reproduction signal for each track separated by the signal separation operation unit 236. , 241-3, 241-4, and M PLLs 242-1, 242-2, 242-3 that perform bit synchronization from the outputs of the equalizers 241-1, 241-2, 241-3, and 241-4. 242-4 and the bit synchronization signal generated by PLLs 242-1, 242-2, 242-2, and 242-4 to generate a code string by binarizing the reproduction signal of each track, for example, a Viterbi detector The binarized reproduction that is the output of the M detectors 243-1, 243-2, 243-3, 243-4 and the detectors 243-1, 243-2, 243-3, 243-4 Detect synchronization pattern on code sequence from signal Synchronization patterns detected by the M synchronization signal detectors 244-1, 244-2, 244-3, 244-4 and the synchronization signal detectors 244-1, 244-2, 244-3, 244-4 M decoders 245-1, 245-2, 245-3, and 245-4 that specify the head position of the data and decode the data sequence from the code string. 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. 21, the restoration unit 260 records the data of each track output from the M decoders 245-1, 245-2, 245-3, and 245-4 in the multitrack demodulation unit 240 at the time of recording. And a data combiner 261 that restores the reproduced data 3 by connecting them in the reverse operation.

  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. 22 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 identification pattern is detected by identifying the head position of the identification pattern in the reproduction signal of the reproduction head R-1, and identification information is obtained (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 407), 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, and the level of the reproduction signal for each scan is individually controlled (step S408).

  Next, based on the track identification information detected by the identification information detection unit 232 in the separation pattern partial processing control unit 238, the reproduction signal of the reproduction head for each scan in the section in which the separation patterns for the units are arranged For each, a reproduction signal corresponding to a separation pattern section reproduced during scanning and a reproduction signal corresponding to a separation pattern section not reproduced during scanning are discriminated, respectively, and a reproduction signal corresponding to the separation pattern section reproduced. Is used as it is, and necessary information is output to the channel estimation calculation unit 234 so that the reproduction signal corresponding to the section of the separation pattern that is not reproduced is replaced with a predetermined value and the channel estimation calculation is performed. (Step S409).

  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 The head position of the separation pattern included in the preamble is identified, and the reproduction head R-1 for each scan and the plurality of reproduction heads are used by using the reproduction signal of these separation pattern portions and the information from the separation pattern portion processing control unit 238. A channel matrix corresponding to the positional relationship in the track width direction during reproduction with the track is calculated (step S410).

  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 S411).

  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 S412).

  Thereafter, the multi-track demodulator 240 decodes the data sequence from the reproduction signal separated for each track (step S413), and the restoration unit 260 concatenates the data for each track to obtain reproduction data 3. (Step S414).

  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. 23 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, the guard band 52 is disposed between the unit-configured track rows 53 including the track # 1, the track # 2, and the track # 3. The preamble 21 recorded on the track # 1, the track # 2, and the track # 3 may be the same as that shown in the above embodiment. 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. 24 shows a recording medium using a plurality of recording heads W-1, W-2, W-3, W-4, W-4, W-5, and W-6 by a double azimuth method and a helical scan method. It is a conceptual diagram of the track format recorded on. 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-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 the above embodiment. 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 reproduction | regeneration signal with respect to the track format of FIG. It is a figure which shows the modification of the track format of FIG. It is a figure which shows the other modification of the track format of FIG. It is a figure which shows the reproduction signal with respect to the track format of FIG. It is a figure which shows the modification of the track format of FIG. It is a figure which shows the example of the track format which makes the track number which can apply this invention 3. It is a figure which shows the modification of the track format of FIG. It is a figure which shows the modification of the track format of FIG. FIG. 16 is a diagram showing a modification of the track format in FIG. 15. 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. 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 modification of the recording device of FIG. FIG. 20 is a flowchart showing an operation flow during unit recording of the recording apparatus of FIG. 19. 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. It is a flowchart which shows the operation | movement of the unit reproduction | regeneration by the reproducing | regenerating 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. It is a flowchart which shows the flow of operation | movement of the unit reproduction | regeneration of the reproducing | regenerating apparatus of FIG. It is a figure which shows the modification of the track format of FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Recording data 2 Magnetic recording medium 3 Reproduction | regeneration data 21 Preamble 22 Data 23 1st preamble 24 2nd preamble 41-1, 41-2, 41-3, 41-4 Gain control pattern 42-1, 42-2, 42-3, 42-4 Synchronization pattern 43-1, 43-2, 43-3, 43-4 Identification pattern 44-1, 44-2, 44-3, 44-4 Separation pattern 51 Unit 100 Recording device 110 Multi Tracking section 111 Data distributor 120 Multitrack recording encoding section 121-1, 121-2, 121-3, 121-4 Recording encoding section 130 Multitrack preamble adding section 131-1, 131-2, 131-3 131-4 Independent preamble adding unit 140 Multitrack recording unit 141-1, 141-2, 141-3, 1 41-4 Output Timing Setting Unit 144-1, 144-2, 144-3, 144-4 Recording Compensation Units 147-1, 147-2, 147-3, 147-4 Recording Amplifier 149 Storage Unit 150 Recording Head Array 200 Reproducing apparatus 210 Reproducing head array 220 Channel reproducing units 221-1, 221-2, 221-3, 221-4 Reproducing amplifiers 224-1, 224-2, 224-3, 224-4 Gain adjusting units 225-1, 225 -2, 225-3, 225-4 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 Operation unit 237 Storage unit 238 Separation pattern partial processing control unit 240 Multitrack demodulation units 241-1 and 241 2, 241-3, 241-4 equalizers 243-1, 243-2, 243-3, 243-4 detectors 244-1, 244-2, 244-3, 244-4 synchronization signal detector 245 1,245-2,245-3,245-4 Decoder 260 Restoration unit 261 Data combiner R-1, R-2, R-3, R-4 Reproducing head W-1, W-2, W-3 , W-4 Recording head

Claims (16)

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 includes data, a reproduction head during reproduction, and a plurality of tracks in the track width direction; A preamble including a separation pattern necessary for detecting a positional relationship is recorded, and the separation pattern of each track is shifted in the traveling direction of the track so that a plurality of separation patterns are not reproduced simultaneously by the reproduction head during reproduction. A playback device for playing back an arranged recording medium,
In the reproduction signal of the reproduction head in the section in which the separation pattern for the unit is arranged, at least the reproduction signal corresponding to the section of the separation pattern that is not reproduced by the reproduction head is replaced with a predetermined value, A playback apparatus comprising: a channel estimation calculation unit that calculates a channel matrix corresponding to a positional relationship in a track width direction during playback between the playback head and the plurality of tracks. The playback apparatus according to claim 1,
Based on the playback signal from the playback head, it is determined which track's recorded code string is the playback signal. Based on the determination result, the separation patterns for the units are arranged. Discriminating between a reproduction signal corresponding to a section of the separation pattern reproduced by the reproduction head and a reproduction signal corresponding to a section of the separation pattern not reproduced by the reproduction head. And a discriminating means for performing reproduction. The playback device according to claim 2,
The preamble further includes an identification pattern for identifying a track;
The discriminating means judges, based on the identification pattern, which track the reproduction signal of the reproduction head is a reproduction signal of. The playback device according to claim 2,
Reproducing signal replacing means for replacing the reproducing signal determined by the determining means and corresponding to the section of the separation pattern that is not reproduced by the reproducing head with a predetermined value and outputting it to the channel estimation calculation unit,
The channel estimation calculation unit calculates the channel matrix using a reproduction signal corresponding to a section of the separation pattern reproduced by the reproduction head and a reproduction signal replaced by the reproduction signal replacement unit. A playback device. The playback apparatus according to claim 1,
The reproducing apparatus, wherein the reproducing head is capable of reproducing a signal across a plurality of tracks. The playback apparatus according to claim 1,
A signal separation calculation unit that separates the reproduction signal of the data for each track from the reproduction signal of the unit of data reproduced by the reproduction head using the channel matrix obtained by the channel estimation calculation unit. And a playback apparatus. The playback apparatus according to claim 1,
A reproducing apparatus comprising a plurality of reproducing heads so that signals can be reproduced with different positional relationships with respect to the plurality of tracks of one unit. The playback apparatus according to claim 1,
When playing back a recording medium in which the separation patterns of the plurality of tracks are arranged in the same section in the direction in which the track travels, the channel estimation calculation unit transmits a playback signal corresponding to the section to the section and the virtual A playback device characterized in that a channel matrix is calculated using each as a playback signal for each of the sections. 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 includes data, a reproduction head during reproduction, and a plurality of tracks in the track width direction; A preamble including a separation pattern necessary for detecting a positional relationship is recorded, and the separation pattern of each track is shifted in the traveling direction of the track so that a plurality of separation patterns are not reproduced simultaneously by the reproduction head during reproduction. A method of playing back an arranged recording medium,
In the reproduction signal of the reproduction head in the section in which the separation pattern for the unit is arranged, at least the reproduction signal corresponding to the section of the separation pattern that is not reproduced by the reproduction head is replaced with a predetermined value, A reproduction method comprising a step of calculating a channel matrix corresponding to a positional relationship in a track width direction during reproduction between the reproduction head and the plurality of tracks. A track format that can be played back by the playback device according to claim 1,
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 includes data, a reproduction head during reproduction, and a plurality of tracks in the track width direction; And a preamble including a separation pattern necessary for detecting the positional relationship, and the separation patterns of each track are shifted in the traveling direction of the track so that a plurality of separation patterns are not reproduced simultaneously by the reproduction head during reproduction. The track format is characterized in that the separation pattern of at least one track is arranged at a position overlapping with a pattern in the preamble of another track in the traveling direction of the track. The track format according to claim 10, wherein
A track format characterized in that the pattern in the preamble of the other track is a pattern for gain control or a pattern for synchronization detection with respect to a reproduction signal. A track format that can be played back by the playback device according to claim 9,
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 includes data, a reproduction head during reproduction, and a plurality of tracks in the track width direction; And a preamble including a separation pattern necessary for detecting the positional relationship, and the separation patterns of each track are shifted in the traveling direction of the track so that a plurality of separation patterns are not reproduced simultaneously by the reproduction head during reproduction. A track format in which the separation patterns of a plurality of tracks are arranged in the same section in the traveling direction of the tracks. A recording medium that can be played back by the playback device according to claim 1,
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 includes data, a reproduction head during reproduction, and a plurality of tracks in the track width direction; A preamble including a separation pattern necessary for detecting a positional relationship is recorded, and the separation pattern of each track is shifted in the traveling direction of the track so that a plurality of separation patterns are not reproduced simultaneously by the reproduction head during reproduction. A recording medium, wherein the separation pattern of at least one track is recorded at a position overlapping with a pattern in the preamble of another track in a traveling direction of the track. The recording medium according to claim 13,
A recording medium, wherein a pattern in the preamble of the other track is a pattern for gain control or a pattern for synchronization detection with respect to a reproduction signal. A recording medium that can be played back by the playback device according to claim 9,
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 includes data, a reproduction head during reproduction, and a plurality of tracks in the track width direction; A preamble including a separation pattern necessary for detecting a positional relationship is recorded, and the separation pattern of each track is shifted in the traveling direction of the track so that a plurality of separation patterns are not reproduced simultaneously by the reproduction head during reproduction. A recording medium in which the separation patterns of a plurality of tracks are recorded in the same section in the traveling direction of the tracks. A reproducing apparatus having a reproducing head and a plurality of tracks constituting a unit which is a unit of signal processing for data reproduction are recorded on the recording medium by the recording head so that data can be reproduced by the reproducing apparatus. A recording / reproducing apparatus comprising:
The recording device comprises:
A multi-track recording encoding unit for encoding data to be recorded for each track;
Necessary for detecting the positional relationship in the track width direction during reproduction between the reproduction head and the plurality of tracks in the code string of the data for each track encoded by the multi-track recording encoding unit. A multi-track preamble adding unit for adding a preamble including a separation pattern;
Each track to which the preamble has been added by the multi-track preamble adding unit so that the preamble and the data of the plurality of tracks are arranged as a unit that is a unit of signal processing for reproducing the data. A multi-track recording unit for recording the data on the recording medium by a recording head,
The playback device
In the reproduction signal of the reproduction head in the section in which the separation pattern for the unit is arranged, at least the reproduction signal corresponding to the section of the separation pattern that is not reproduced by the reproduction head is replaced with a predetermined value, A recording / reproducing apparatus, comprising: a channel estimation calculation unit that calculates a channel matrix corresponding to a positional relationship in a track width direction during reproduction between the reproduction head and the plurality of tracks.

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