JP2008282501A - Device and method for reproducing, device and method for recording, recording/reproducing device, data format, and recording medium - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To stabilize data reproduction with respect to track shifting caused by external disturbances in a magnetic recording/reproducing system for recording a plurality of tracks being a signal processing unit for data reproduction in a medium by a recording head, reproducing a signal of each track by a reproducing head capable of reproducing the signal over the plurality of the tracks, collecting such reproduced signals into one unit, and performing signal processing to separate the reproduced signals of the respective tracks. <P>SOLUTION: From the reproduced signals of separation patterns in a plurality of preambles consecutive across data, based on a plurality of channel matrixes obtained as a result of channel estimation calculation, a variable channel matrix is estimated within the section of the data and, by using this variable channel matrix, the reproduced signal is separated from the reproduced signal of one unit for each track. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a reproducing apparatus and reproducing method for reproducing data from a recording medium in which a unit of signal processing for reproducing data is divided into a plurality of tracks, a recording apparatus, a recording method, and a recording / reproducing related thereto. The present invention relates to an apparatus, a data format, and a recording medium.

  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 not foreseeable from the publicly known technology 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. 20 is a diagram showing the configuration of a recording apparatus 500 that employs the magnetic recording / reproducing method described above.

  As shown in the figure, the recording apparatus 500 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. 21 is a flowchart showing the unit recording operation by the recording apparatus 500. 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 number of tracks to be processed (step S501).

  Each distributed data is encoded into a code string in consideration of recording / reproducing characteristics of the magnetic recording medium 2 by the recording encoding units 121-1, 121-2, and 121-3 of the multi-track recording encoding unit 120, respectively. Is done. At this time, information necessary for data demodulation, such as a demodulation synchronization pattern, is also added to the data code string (step S502).

  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 S503).

  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 S504).

  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 track direction.

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

  FIG. 22 is a diagram showing a configuration of a reproducing apparatus 600 that employs the above-described magnetic recording / reproducing method.

  As shown in the figure, the reproducing apparatus 600 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, 243-3 such as a Viterbi detector, and a detector 243 generate a code string by binarizing 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, , Sync 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 244-2 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. 23 is a flowchart showing a unit reproduction operation flow of the reproduction apparatus 600. In this reproducing apparatus 600, 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 S601).

  Next, after the gain adjustment units 224-1, 224-2, and 224-3 adjust the amplitude levels of the outputs of the reproduction amplifiers 221-1, 221-2, and 221-3, the gain adjustment unit 224- The outputs of 1, 244-2 and 224-3 are converted into digital values by the A / D converters 225-1, 225-2, and 225-3 and output to the synchronization signal detector 231 (step S602).

  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 S603). .

  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 of one unit (step S604), each reproducing head is based on this channel matrix. A reproduction signal for each of the tracks R-1, R-2, and R-3 is separated from the reproduction signal for one unit reproduced by R-1, R-2, and R-3 (step S605).

  After this, the multi-track demodulator 240 decodes the data sequence from the reproduction signal for each track (step S606), and the reconstruction unit 260 concatenates the data for each track to obtain reproduction data 3 ( Step S607).

  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 / reproducing method, there is, for example, an improvement in followability with respect to a track shift.

  In other words, in the above magnetic recording / reproducing system, when tracking becomes unstable due to disturbance or the like during reproduction, the positional relationship in the track width direction with respect to each track of each reproducing head fluctuates. If information cannot be obtained, reproduction may become unstable.

  In view of such circumstances, the present invention intends to provide a reproducing apparatus, a reproducing method, a recording apparatus, a recording method, a recording / reproducing apparatus, a data format, and a recording medium capable of stabilizing data reproduction against a track shift. It is.

  In order to solve the above-described problem, a reproducing apparatus according to the present invention includes a plurality of tracks, and a reproducing head capable of reproducing data for each track and a signal across one or more of the tracks. A preamble including a pattern necessary for detecting a positional relationship in the track width direction during reproduction with the plurality of tracks, and a signal for reproducing the data of the plurality of tracks and the preamble As a unit that is a unit of processing, a device that reproduces the data from a recording medium in which a plurality of units are continuously recorded in the track direction, based on the reproduction signal of the pattern for each unit, A channel estimation calculation unit for calculating a channel matrix corresponding to the positional relationship in the track width direction during reproduction between the reproduction head and the plurality of tracks A channel matrix estimator that estimates a variable channel matrix within the data interval from the channel matrix obtained by the channel estimation calculator based on the reproduction signal of the pattern in the unit; and the channel matrix A signal separation calculation unit that separates the reproduction signal of the data for each track from the reproduction signal of the data for one unit reproduced by the reproduction head using the variable channel matrix estimated by the estimation unit; It comprises.

  According to the present invention, data reproduction with respect to track deviation is made possible by making the channel matrix corresponding to the positional relationship between the reproduction head and the plurality of tracks in the track width direction variable in accordance with the track deviation situation within the data section. Can be stabilized.

  In the reproduction apparatus of the present invention, the channel matrix estimation unit uses the plurality of channel matrices obtained by the channel estimation calculation unit based on the reproduction signals of the pattern in the plurality of consecutive units. A variable channel matrix may be estimated within the data interval. As a result, the track shift state can be detected more accurately, and the data reproduction against the track shift can be stabilized.

  In the reproduction apparatus of the present invention, the channel matrix estimation unit may calculate the data from a plurality of channel matrices respectively obtained by the channel estimation calculation unit based on reproduction signals of the pattern in a plurality of consecutive units. A plurality of channel matrices corresponding to each of the sections obtained by dividing the section are estimated, and the signal separation calculation unit uses the plurality of channel matrices obtained by the channel matrix estimation unit for each individual section. The reproduction signal of the data for each track may be separated from the reproduction signal of the data for one unit reproduced by the reproduction head. As a result, an appropriate channel matrix corresponding to the track shift state can be obtained for each section obtained by dividing the data section, and the data reproduction against the track shift can be stabilized.

  In the reproduction apparatus of the present invention, the channel matrix estimation unit is configured by linear interpolation from a plurality of channel matrices obtained by the channel estimation calculation unit based on the reproduction signals of the patterns in the plurality of consecutive units. A plurality of channel matrices respectively corresponding to the individual sections of the data may be estimated. By using linear interpolation in this way, it is possible to obtain an appropriate channel matrix corresponding to the track shift situation for each section obtained by dividing the data section, and to stabilize the data reproduction against the track shift. be able to.

  In the reproduction apparatus of the present invention, the channel matrix estimation unit includes the two units from two channel matrices obtained by the channel estimation calculation unit based on the reproduction signals of the pattern in the two consecutive units. A variable channel matrix may be estimated within a section of data sandwiched between the preambles. In addition, the channel matrix estimation unit is behind the both of the plurality of patterns from the plurality of channel matrices obtained by the channel estimation calculation unit based on the reproduction signals of the patterns in the plurality of consecutive units. It is also possible to estimate a variable channel matrix within the data section located at.

  As the pattern, a separation pattern composed of a signal having a recording wavelength equal to or greater than the minimum recording wavelength and disposed at a unique position for each track can be used. Also, tracking servo information may be used.

  In the reproducing apparatus of the present invention, the signal separation calculation unit obtains a generalized inverse matrix of the variable channel matrix estimated by the channel matrix estimation unit, and the generalized inverse matrix and the reproduction head reproduce The data reproduction signal for each track may be separated from the data reproduction signal for one unit. Further, the signal separation calculation unit separates the reproduction signal of the data for each track by a MMSE (Minimum Mean Squared Error) method from the variable channel matrix estimated by the channel matrix estimation unit. Also good.

  The reproducing apparatus of the present invention may include 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.

  A playback method according to another aspect of the present invention includes a plurality of tracks, a playback head capable of playing back data over each of the tracks, and the plurality of tracks. And a preamble including a pattern necessary for detecting the positional relationship in the track width direction during reproduction, and a unit of signal processing for reproducing the data of the plurality of tracks and the preamble The unit is a method for reproducing the data from a recording medium in which a plurality of units are continuously recorded in the track direction, and based on the reproduction signal of the pattern for each unit, the reproduction head and the unit Calculating a channel matrix corresponding to the positional relationship in the track width direction during reproduction with a plurality of tracks, and a plurality of consecutive units. Estimating a variable channel matrix within a section of the data using a plurality of channel matrices respectively obtained in the channel matrix calculation step based on the reproduction signal of the pattern in the network; and Separating the data reproduction signal for each track from the data reproduction signal for the unit reproduced by the reproduction head using the variable channel matrix.

  According to the present invention, by changing the channel matrix corresponding to the positional relationship in the track width direction between the reproducing head and the plurality of tracks in the data section, the data reproduction for the track deviation can be performed. Stabilization can be achieved.

  A recording apparatus according to another aspect of the present invention is an apparatus for recording a plurality of tracks on a recording medium, the multitrack recording encoding unit encoding data to be recorded for each track, and the multitrack recording Track width at the time of reproduction of the reproduction head and the plurality of tracks each capable of reproducing a signal across one or more of the tracks in the code string of the data for each track encoded by the encoding unit A multi-track preamble adding unit for adding a preamble including a pattern necessary for detecting the positional relationship of directions, and the preamble and the data of the plurality of tracks as a unit of signal processing for reproducing the data. As a unit, the multi-track preamplifier is arranged so that a plurality of units are arranged in the track direction. Comprising a multi-track recording section for recording on the recording medium by the recording head of data of each of the tracks the preamble has been added by the bull adding unit.

  According to the present invention, the preamble and data of a plurality of tracks can be recorded on a recording medium by arranging a plurality of units in the track direction as a unit that is a unit of signal processing for reproducing data. In the playback apparatus of the present invention, each channel matrix is obtained by channel estimation calculation from the playback signals of patterns in a plurality of consecutive units, and a variable channel matrix is obtained within the data interval using these channel matrices. By estimating and using the estimated variable channel matrix, it is possible to separate the data reproduction signal for each track from the data reproduction signal for the unit reproduced by the reproduction head. Become.

  In the recording apparatus of the present invention, the multi-track preamble adding unit adds the preamble to the data other than the data recorded at the end of the track and records the data at the end of the track. The preamble may be added to the data before and after the data. Thus, in the playback device of the present invention, a plurality of channel matrices are calculated by channel estimation calculation from the playback signals of the patterns in the two preambles arranged before and after the data, and the plurality of channel matrices are used. This makes it possible to estimate a variable channel matrix within a data interval.

  According to another aspect of the present invention, there is provided a recording method for recording a plurality of tracks on a recording medium, the step of encoding data to be recorded for each track, and for each of the encoded tracks. A pattern necessary for detecting the positional relationship in the track width direction during reproduction between the reproduction head capable of reproducing a signal over one or more of the tracks and the plurality of tracks in the data code string And adding a plurality of units in the track direction as a unit that is a unit of signal processing for reproducing the data, the preamble and the data of the plurality of tracks. In addition, the data for each track to which the preamble is added is recorded on the recording medium by the recording head. Tsu; and a flop.

  According to the present invention, the preamble and data of a plurality of tracks can be recorded on a recording medium by arranging a plurality of units in the track direction as a unit that is a unit of signal processing for reproducing data. In the playback apparatus of the present invention, each channel matrix is obtained by channel estimation calculation from the playback signals of patterns in a plurality of consecutive units, and a variable channel matrix is obtained within the data interval using these channel matrices. By estimating and using the estimated variable channel matrix, it is possible to separate the data reproduction signal for each track from the data reproduction signal for the unit reproduced by the reproduction head. Become.

  A data format according to another aspect of the present invention includes a plurality of tracks, and each track has data, a reproducing head capable of reproducing a signal across the one or more tracks, and the plurality of tracks. And a preamble including a pattern necessary for detecting a positional relationship in the track width direction during reproduction, and the data of the plurality of tracks and the preamble are used for signal processing for reproducing the data. As a unit, each unit is continuously arranged on the plurality of tracks.

  According to this data format, in the playback apparatus of the present invention, each channel matrix is obtained by channel estimation calculation from a playback signal of a pattern in a plurality of consecutive units, and the data within a data section is obtained using these plurality of channel matrices. The variable channel matrix is estimated by using the estimated variable channel matrix, and the reproduction signal of the data for each track is obtained from the reproduction signal of the data for one unit reproduced by the reproduction head. It becomes possible to separate.

  The data format of the present invention may be one in which the preamble is arranged before and after the data. Thereby, in the playback device of the present invention, a plurality of channel matrices are calculated by channel estimation calculation from the playback signals of the patterns in the two preambles arranged before and after the data, and the plurality of channel matrices are obtained. Can be used to estimate a variable channel matrix within a data interval.

  A recording medium according to another aspect of the present invention has a plurality of tracks, and for each track, data, a reproducing head capable of reproducing a signal across one or more of the tracks, and the plurality of tracks And a preamble including a pattern necessary for detecting the positional relationship in the track width direction at the time of reproduction, and the data of the plurality of tracks and the preamble are used for signal processing for reproducing the data. It is recorded continuously in the track direction as a unit.

  According to the reproducing apparatus, reproducing method, recording apparatus, recording method, recording / reproducing apparatus, data format, and recording medium of the present invention, it is possible to stabilize data reproduction against track deviation.

  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 magnetic recording / reproducing system using a multi-head will be described. Here, the number of recording heads is M, the number of reproducing heads is N, and in this embodiment, M = 3 and N = 3.

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

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

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

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

  The multitrack preamble adding unit 130 adds M 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. 2 is a flowchart showing the unit recording operation by the recording apparatus 100. In this recording apparatus 100, first, the input recording data 1 is configured by the multitracking unit 110 as data (M = 3) of recording heads W-1, W-2, W-3, that is, a unit. The data is distributed to the data corresponding to the number of tracks to be performed (step S101).

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

  Next, 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 S103).

  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 S104).

  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 track direction.

  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 according to the first embodiment of the present invention.

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

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

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

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

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

  The signal separation processing unit 230 detects the synchronization pattern detected by the synchronization signal detector 231 and the synchronization signal detector 231 that detects the synchronization pattern from the outputs of the A / D converters 225-1, 225-2, and 225-3. A channel estimation calculation unit 232 that specifies a start position of a separation pattern and performs channel estimation calculation using a reproduction signal of the separation pattern, and a channel estimation calculation from reproduction signals of a plurality of consecutive preambles across data A channel matrix estimation unit 233 that estimates a variable channel matrix within a data interval using a plurality of channel matrices respectively obtained by the above, and a variable channel within a data interval estimated by the channel matrix estimation unit 233 A reproduction signal for one unit reproduced by each reproducing head R-1, R-2, R-3 using a matrix Comprising al, a signal separation calculation section 234 for separating the reproduced signal of each track.

  The signal separation processing unit 230 has a storage unit (not shown) that stores information such as data 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 multitrack demodulator 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 234. , 241-3, M PLLs 242-1, 242-2, and 242-3 that perform bit synchronization from the outputs of the equalizers 241-1, 241-2, and 241-3, and PLLs 242-1 and 242-2 , 242-3 to generate a code string by binarizing the reproduction signal for each track using the bit synchronization signal generated by M, 243-3, 243-2, 243, 243, for example. -3 and M synchronization signal detectors 244-1 and 244 for detecting a synchronization pattern on the code string from the binarized reproduction signals output from the detectors 243-1, 243-2 and 243-3 -2, 244-3 and synchronous signal M decoders 245-1 and 245-that specify the data start position based on the synchronization patterns detected by the detectors 244-1, 244-2 and 244-3 and decode the data sequence from the code sequence. 2,245-3. Note that the multitrack demodulation unit 240 has a storage unit (not shown) that stores information such as data necessary for performing the above processing.

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

  FIG. 5 is a flowchart showing a unit reproduction operation flow of the reproduction apparatus 200. In the reproducing apparatus 200, first, one unit of the magnetic recording medium 2 is formed by N reproducing heads R-1, R-2, and R-3 that can reproduce signals from one or more adjacent tracks. A signal is reproduced from a plurality of tracks (step S201).

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

  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 S203). .

  Next, the channel estimation calculation unit 232 identifies the start position of the separation pattern arranged in each reproduction signal based on the synchronization pattern detected by the synchronization signal detector 231, and stores the reproduction signal of the separation pattern. Then, a channel matrix corresponding to the positional relationship in the track width direction between each reproducing head R-1, R-2, R-3 and a plurality of tracks for one unit is obtained by a predetermined channel estimation calculation (step S204).

  Next, the channel matrix estimation unit 233 uses a plurality of channel matrices obtained by channel estimation calculation from reproduced signals of separation patterns in a plurality of consecutive preambles with data sandwiched on a track, and within the section of the data To estimate a variable channel matrix (step S205).

  Next, the signal separation calculation unit 234 reproduces data by the reproduction heads R-1, R-2, and R-3 based on the channel matrix variable in the data interval estimated by the channel estimation calculation unit 232. The reproduced signal for each track is separated from the reproduced signal for one unit (step S206).

  Thereafter, the multi-track demodulator 240 decodes the data sequence from the reproduction signal for each track (step S207), and the reconstruction unit 260 concatenates the data for each track to obtain reproduction data 3 ( Step S208).

  FIG. 6 is a conceptual diagram of a data format on the magnetic recording medium 2 on which recording is performed by the recording apparatus 100 of the present embodiment.

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

  Here, a unit 53 as a unit of signal processing for reproducing data is a group of M preambles 21 and M data 22 in each of M tracks # 1, # 2, and # 3. (1), 53 (2),..., 53 (E). A group of M tracks # 1, # 2, and # 3 is hereinafter referred to as a “unit configuration track sequence”.

  In the unit configuration track row 51, a plurality of units 53 (1), 53 (2),..., 53 (E) are continuously arranged in the track direction. In this embodiment, for example, two channel matrices respectively obtained by channel estimation calculation based on a plurality of preambles 21 that are continuous across the data 22 on the track, for example, reproduction signals of separated patterns in the two preambles 21. Therefore, a plurality of channel matrices corresponding to the respective sections obtained by dividing the section of the data 22 are estimated as variable channel matrices in the section of the data 22. For this reason, the preamble 21 (E + 1) is also added after the last data 22 (E) of each of M tracks # 1, # 2, and # 3.

  In the magnetic recording medium 2, S unit-constituting track trains 51 are arranged in parallel to each other, and between the adjacent unit-constituting track trains 51, there is a non-recorded area called a guard band 52. Is provided. The purpose of the guard band 52 is to prevent the tracks of the adjacent unit configuration track row 51 from being reproduced. Reference numeral 26 denotes a margin provided at the end of the track, and nothing is described here.

  FIG. 7 is a diagram showing an example of the track shift of each of the reproducing heads R-1, R-2, R-3 on the format shown in FIG.

  Assuming that the moving direction of the reproducing heads R-1, R-2, and R-3 is the direction indicated by arrow 13, the preambles from the tracks # 1, # 2, and # 3 are the preamble 21 (1) and the preamble 21 (2). Are played in this order. For example, when the tracking becomes unstable due to disturbance or the like during reproduction, each reproduction head R-1, R-2, R-3 and each track # 1, # 2, # 3 and the like are located at the position of the preamble 21 (1). However, the position of the preamble 21 (2) may deviate from the appropriate position relation. In the example of FIG. 7, at the position of the preamble 21 (2), the positional relationship between each reproducing head R-1, R-2, R-3 and each track # 1, # 2, # 3 is shown from an appropriate state. A state where the track width is shifted by 50% is shown in the middle and lower part. In such a case, the quality of the separated signal obtained based on the reproduction signal of the preamble 21 (1) is degraded in the latter half of the data 22 (1) section. Although the description has been given here assuming that the reproducing heads R-1, R-2, and R-3 move, the reproducing heads R-1, R-2, and R-3 are fixed, and the magnetic recording medium 2 is denoted by reference numeral 14. The same applies when moving in the direction of the arrow.

  Therefore, in this embodiment, a variable channel matrix is estimated within a section of the data based on a plurality of channel matrices obtained as a result of channel estimation calculation from a plurality of consecutive preamble playback signals with data sandwiched therebetween. The variable channel matrix is used to separate the reproduction signal for each track from the reproduction signals of the reproduction heads R-1, R-2, and R-3 for one unit.

  Before describing the operation of estimating the channel matrix, the configuration of the preamble 21 recorded on the magnetic recording medium 2 will be described.

  FIG. 8 is a diagram showing the configuration of the preamble 21 recorded on the magnetic recording medium 2.

  As shown in the figure, the preamble 21 includes a first preamble 23, a synchronization pattern 24, and a second preamble 25. On the track, the first preamble 23, the synchronization pattern 24, and the second preamble 25 are arranged in this order from the top. Data 22 is arranged after the second preamble 25. Data 22 is a recording code string created by the recording encoding units 121-1, 121-2, and 121-3 of the recording apparatus 100 of FIG. The first preamble 23, the synchronization pattern 24, and the second preamble 25 are added to the recording code string by the preamble adding units 131-1, 131-2, and 131-3.

  At the time of reproduction, the first preamble 23 is reproduced by the reproduction amplifiers 221-1, 221-2, 221-3 by the gain adjusting units 224-1, 224-2, 224-3 in the reproduction apparatus 200 shown in FIG. Is used as a learning signal for gain control. The first preamble 23 is also used by the synchronization signal detector 231 for learning for bit synchronization detection, level adjustment of a reproduction signal, and the like as necessary.

  The synchronization pattern 24 is used by the synchronization signal detector 231 as information for knowing the start position of the second preamble 25 and the start position of the data 22.

  The second preamble 25 corresponds to the positional relationship in the track width direction between a plurality of reproducing heads R-1, R-2, R-3 and a plurality of tracks # 1, # 2, # 3 for one unit during reproduction. This is a pattern used for obtaining the channel matrix to be calculated by the channel estimation calculation unit 232.

  The second preamble 25 is composed of separation patterns 31, 32, and 33 arranged so that the positions in the track direction do not overlap with adjacent tracks for each of the tracks # 1, # 2, and # 3. The That is, the separation pattern 31 of the track # 1 is recorded in the T1 section, the separation pattern 32 of the track # 2 is recorded in the T2 section, and the separation pattern 33 of the track # 3 is recorded in the T3 section. As a result, there are three types of separation patterns corresponding to the number of tracks. A gap 34 for a predetermined time is provided between the separation patterns 31, 32, 33 of adjacent tracks, and the separation patterns 31, 32, 32 of each track # 1, # 2, # 3 in the unit. 33 does not overlap.

  The separation patterns 31, 32, and 33 are recorded at a predetermined recording wavelength equal to or greater than the minimum recording wavelength.

  The channel estimation calculation unit 232 performs channel estimation calculation using the reproduction signals of the separation patterns 31, 32, and 33, and generates a channel matrix as a result. This channel matrix corresponds to position information in the track width direction of the individual reproducing heads R-1, R-2, and R-3 for the tracks # 1, # 2, and # 3 in one unit, in other words. Information indicating which track in the unit overlaps with which track in each unit, each reproducing head R-1, R-2, R-3.

  Next, details of the channel matrix estimation operation by the channel matrix estimation unit 233 will be described. In this detailed description, a channel matrix for each section obtained by dividing the data section is adopted as an example of a variable channel matrix within the data section.

  The channel matrix estimator 233 is obtained by the channel estimator 232 by the channel estimator 232 based on the reproduced signals of the separated patterns in the preamble 21 of a plurality of consecutive units, for example, two units. A plurality of channel matrices corresponding to individual divided sections of the data 22 between the two preambles 21 are estimated using one channel matrix.

  FIG. 9 is a diagram showing a specific example of the channel matrix estimation operation by the channel matrix estimation unit 233.

  In this example, the section of the data 22 (1) between the two preambles 21 (1) and 21 (2) is divided into n. Here, n = 3. In this case, the channel matrix estimation unit 233 uses, for example, linear interpolation using two channel matrices respectively obtained by channel estimation calculation from reproduction signals of separation patterns in the two preambles 21 (1) and 21 (2). For example, n channel matrices corresponding to the respective sections obtained by dividing the section of the data 22 (1) by n are estimated.

  In this example, the preconditions for estimating the channel matrix are shown. The maximum value used for the channel matrix is 1.0, and the minimum value is 0.0. For example, in the estimation calculation, when the value of the channel matrix is less than 0.0, it is fixed to 0.0, and when it exceeds 1.0, it is fixed to 1.0. The widths of the reproducing heads R-1, R-2, and R-3 are 1.5 times the track width. That is, the width of the reproducing heads R-1, R-2, and R-3 is 1.5 times the head width of the recording heads W-1, W-2, and W-3, and the individual reproducing heads R-1 , R-2, and R-3 can reproduce signals from a plurality of tracks. In the case of FIG. 9, the reproducing head R-1 reproduces signals from the tracks # 1 and # 2, and the reproducing head R-2 reproduces signals from the three tracks # 1, # 2, and # 3. The reproducing head R-3 reproduces signals from the track # 2 and the track # 3.

  The channel matrix estimation unit 233 first compares the two channel matrices 34 and 35 obtained by the channel estimation calculation from the reproduction signals of the separation patterns in the two preambles 21 (1) and 21 (2), Detect maximum difference and positive / negative transition direction. First, the shift amount is obtained from the maximum difference and the given number of divisions. Next, the shift amount is obtained from the maximum difference and the given number of divisions. Here, since n = 3 and only the T2 section is estimated, a value that is ½ times the maximum difference is set as the displacement amount. That is, since the maximum difference is 0.5, 0.25 is obtained as the displacement amount. Then, based on the shift amount and the shift direction, the channel matrix 36 shown in FIG. 9 is estimated as the channel matrix corresponding to the T2 interval that is the middle of the data interval. Further, the channel matrix estimation unit 233 uses the channel matrix 34 obtained by the channel estimation calculation from the reproduction signal of the preamble 21 (1) as the channel matrix estimation result for the T1 section of the data section, and further the preamble 21 (2). The channel matrix 35 obtained from the reproduced signal by channel estimation calculation is used as the channel matrix estimation result for the T3 section of the data section.

  In addition, here, it is assumed that the T2 section is estimated with n = 3, and ½ of the maximum difference is the transition amount. However, for example, when n = 4, the sections of T2 and T2 among the sections of T1 to T4 are selected. When estimating, 1/3 times the maximum difference is set as the shift amount.

  The signal separation processing by the signal separation calculation unit 234 is performed for each of the divided sections T1, T2, and T3 using each channel matrix estimated for each of the divided sections T1, T2, and T3. That is, the signal separation calculation unit 234 performs signal separation processing using the channel matrix 34 obtained by the channel estimation calculation from the playback signal of the preamble 21 (1) in the T1 interval, and the channel matrix estimation unit 233 estimates in the T2 interval. The signal separation process is performed using the channel matrix 36, and the signal separation process is performed using the channel matrix 35 obtained by the channel estimation calculation from the reproduction signal of the preamble 21 (2) in the T3 interval.

  Note that examples of the calculation method of the signal separation processing by the signal separation calculation unit 234 include a method of obtaining a generalized inverse matrix for the channel matrix. 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.

  As described above, according to the present embodiment, based on a plurality of channel matrices respectively obtained as a result of channel estimation calculation from a plurality of preamble reproduced signals sandwiching data, within the section of the data. To estimate a variable channel matrix, and use this variable channel matrix to separate the reproduction signal for each track from the reproduction signal of each reproduction head R-1, R-2, R-3 for one unit. By doing so, even when the positional relationship in the track width direction between each reproducing head and each track for one unit deviates from an appropriate state due to a track shift due to a disturbance or the like, data reproduction can be performed satisfactorily. become.

  Note that, in the above, it is variable in the data section reflecting the situation of the track deviation from the two channel matrices obtained by the channel estimation calculation based on the reproduction signal of the separation pattern in the preamble in the two consecutive units. Although the channel matrix is estimated, each data section is obtained from three or more channel matrices obtained by channel estimation calculation based on a reproduction signal of a separation pattern in a preamble in three or more consecutive units. A variable channel matrix may be estimated every time and used for signal separation processing. Furthermore, the plurality of preambles to be referred to do not necessarily have to be continuous, and it is sufficient that information for performing channel estimation calculation can be obtained. Further, as a channel matrix interpolation method by the channel matrix estimation unit 233, a method other than linear interpolation may be used.

  In FIG. 9, the lengths of the divided sections T1, T2, and T3 to which the channel matrices 34, 35, and 36 are applied are equal, but the divided sections to which the channel matrices 34, 35, and 36 are applied, respectively. The lengths need not be uniform. For example, as shown in FIG. 10, the data section is equally divided into four, and the signal separation process is performed using the channel matrix 34 obtained from the reproduction signal of the separation pattern in the first preamble 21 (1) in the T1 section. In the T2 section and the T3 section, signal separation processing is performed using the channel matrix 36 interpolated from the two channel matrices 34 and 35 by the channel matrix estimation unit 233, and in the T4 section, the separation pattern in the preamble 21 (2) is performed. Separation processing may be performed using the channel matrix 35 obtained from the reproduced signal.

  Further, the data section is equally divided into five, and signal separation processing is performed using the channel matrix 36 interpolated by the channel matrix estimation unit 233 from the T2 section to the T4 section, or the data section is equally divided into seven. Thus, the signal separation processing may be performed using the channel matrix 36 interpolated by the channel matrix estimation unit 233 from the T3 interval to the T5 interval. The same applies when the data section is divided into other numbers.

  Further, the data section is equally divided into two, and in the T1 section, signal separation processing is performed using the channel matrix 34 obtained from the reproduction signal of the separation pattern in the preamble 21 (1), and in the T2 section, the preamble 21 (2). Signal separation processing may be performed using the channel matrix 35 obtained from the reproduction signal of the separation pattern. In this method, it is not necessary to interpolate the channel matrix 36 by the channel matrix estimation unit 233.

  Further, assuming that the division number n of the data section is 1, the channel matrix 34 obtained from the reproduction signal of the separation pattern in the preamble 21 (1) and the channel matrix obtained from the reproduction signal of the separation pattern in the preamble 21 (2). 35 may be selected under a predetermined condition to perform the separation process. Also in this case, the channel matrix estimation unit 233 does not need to interpolate the channel matrix 36.

  The present invention regenerates a channel matrix suitable for the system and the situation at that time from a predetermined plurality of channel matrices, and uses this to reproduce data more satisfactorily.

  In the present invention, the configuration of the preamble 21 is not limited to that shown in FIG. 8, and any configuration can be used as long as it can be used for the calculation of the channel matrix.

  FIG. 11 is a diagram showing another example of the data format according to the present invention. In the data format of FIG. 6 described above, 2 obtained respectively by channel estimation calculation from the reproduction signals of the separated patterns in two preambles 21 (1) and 21 (2) that are continuous across the data 22 (1). The variable channel matrix is estimated within the section of the data 22 (1) using the channel matrix of, for example, a plurality of preambles arranged in front of the data 22 (2), for example, two Estimating a variable channel matrix within the section of data 22 (2) using two channel matrices obtained by channel estimation calculation from the reproduced signals of the separated patterns in preambles 21 (1) and 21 (2). The same effect can be expected. In such a case, the preamble 21 (E + 1) after the last data 22 (E) shown in FIG. 6 is not necessary. In this case, signal separation processing can be performed even if the reproduction signals of the preamble 21 and the data 22 are not stored in the storage unit of the signal separation processing unit 230.

  Further, in the above embodiment, as a pattern necessary for detecting the positional relationship in the track width direction at the time of reproduction between each reproduction head R-1, R-2, R-3 and a plurality of tracks for one unit, Although the separation pattern as shown in FIG. 8 is used, the present invention is not limited to this, and for example, tracking servo information or the like can be used. In this case, a summary of the positional relationship between each recording pattern of the tracking servo information and each reproducing head in units is generated as channel estimation information.

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

  Furthermore, in the above-described embodiment, a case where a 3 × 3 matrix is calculated as channel estimation information has been described. However, for example, a 4 × 4 matrix or other square matrix may be generalized inversely. It is possible to perform signal separation processing by obtaining a matrix. Furthermore, a generalized inverse matrix may be obtained in the same manner for a matrix other than a square matrix.

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

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

  The amount of information for gain control may be increased by additionally arranging the gain control pattern arranged in the first preamble 23 behind the synchronization pattern 24.

  The same pattern may be adopted as the gain control pattern arranged in the first preamble 23 and the separation pattern arranged in the second preamble 25.

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

  (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. 12 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. In this embodiment, M = 3 and N = 3. And

  As shown in the figure, the recording apparatus 300 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 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 includes a storage unit 149 that stores recording data for at least one unit, a single output timing setting unit 141 that gives a desired timing to a recording code string to which a preamble is added, and a recording compensation process. One recording compensation unit 144 to be performed and one recording amplifier that drives the recording head W-1 based on the recording code string after the recording compensation process are configured.

  FIG. 13 is a flowchart showing a flow of operations during unit recording of the recording apparatus 300. In the recording apparatus 300, first, the input recording data 1 is distributed to M (M = 3) pieces of data (data for each track) by the multitracking unit 110 (step S301).

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

  Next, at a predetermined position of each encoded recording data, the preamble adding units 131-1, 131-2, and 131-3 of the multi-track preamble adding unit 130 control reproduction of data in units. A necessary pattern is added as a preamble to obtain a recording code string (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.

  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 track direction.

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

  FIG. 14 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 includes a recording encoding unit 121 that records and encodes recording data in a predetermined unit, for example, recording data for a predetermined number of tracks, and encoded recording data for each track. A preamble adding unit 131 that adds a specific preamble to each track, a storage unit 149, an output timing setting unit 141 that gives a desired timing to the recording code string to which the preamble is added, and a recording compensation unit that performs recording compensation processing. 144 and a recording amplifier 147 for driving the recording head W-1 based on the recording code string after the recording compensation process. That is, the multitrack recording unit 110 (data distributor 111) is omitted from the configuration of the recording apparatus 300 shown in FIG. 12, and the multitrack recording encoding unit 120 is configured by one recording encoding unit 121. The multitrack preamble adding unit 130 is composed of one preamble adding unit 131.

  FIG. 15 is a flowchart showing a unit recording operation flow of the recording apparatus 301.

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

  Next, a pattern necessary for control for reproducing data in units is added as a preamble to a predetermined position of each encoded recording data by the preamble adding unit 131, and a recording code string is obtained. (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.

  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 track direction.

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

  FIG. 16 is a diagram showing a configuration of a reproducing apparatus 400 in the magnetic recording / reproducing system according to the second embodiment of the present invention.

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

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

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

  The signal separation processing unit 230 detects the synchronization pattern from the output of the A / D converter 225, and specifies the start position of the separation pattern based on the synchronization pattern detected by the synchronization signal detector 231. Then, a channel estimation calculation unit 232 that performs channel estimation calculation using the reproduction signal of this separation pattern, and a plurality of channel matrices respectively obtained by channel estimation calculation from reproduction signals of a plurality of preambles that are continuous across data A channel matrix estimator 233 that estimates a variable channel matrix within a data interval, and each reproduction head R− using a channel matrix that is estimated by the channel matrix estimator 233 and that is variable within the data interval. A signal component that separates the reproduction signal for each track from the reproduction signal for one unit reproduced by 1 A calculation unit 234, is disposed between the synchronization signal detector 231 and the signal separation calculation section 234, and a storage unit 235 for storing the reproduced signal of at least one unit.

  As shown in FIG. 4, the multi-track demodulation unit 240 performs M equalizers 241-1 and 241− that perform equalization processing on the reproduction signal for each track separated by the signal separation operation unit 234. 2, 241-3, M PLLs 242-1, 242-2, and 242-3 that perform bit synchronization from the outputs of the equalizers 241-1, 241-2 and 241-3, and PLLs 242-1 and 242- For example, M detectors 243-1, 243-2, such as a Viterbi detector, generate a code string by binarizing the reproduction signal for each track using the bit synchronization signal generated at 2 242-3. 243-3, and M synchronization signal detectors 244-1 that detect a synchronization pattern on the code string from the binarized reproduction signals that are the outputs of the detectors 243-1, 243-2, and 243-3. Synchronized with 244-2 and 244-3 M decoders 245-1 and 245 for decoding the data string from the code string by specifying the data start position based on the synchronization patterns detected by the signal detectors 244-1, 244-2 and 244-3 -2, 245-3. Note that the multitrack demodulation unit 240 has a storage unit (not shown) that stores information such as data necessary for performing the above processing.

  Returning to FIG. 16, the restoration unit 260 operates the data of each track output from the M decoders 245-1, 245-2, and 245-3 in the multitrack demodulation unit 240 in the reverse operation to that at the time of recording. And a data combiner 261 for recovering the reproduction data 3 by connecting them.

  Note that the track tracing during reproduction by the single head is repeated at least as many times as the number of recording tracks of one unit. That is, the tracing may be repeated more times than the number of tracks. At that time, all tracks for one unit are traced at least once. In the storage unit 235, signals for units reproduced at each position where the reproducing head R-1 has moved, that is, signals 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. 17 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).

  The synchronization signal detector 231 detects the synchronization pattern for knowing the start position of the separation pattern from the output of the A / D converter 225 (step S403), and then the track reproduction signal is stored in the storage unit 235. (Step S404).

  Next, it is determined whether or not the reproduction signal for one unit is stored in the storage unit 235 (step S405), and when the reproduction signal for one unit is not yet stored in the storage unit 235,

The reproducing head R-1 is shifted to the next position in the track width direction (step 406), and the operations from step S401 to step S405 are repeated.

  When the reproduction signal for one unit is stored in the storage unit 235, the channel estimation calculation unit 232 reads out the reproduction signal for one unit stored in the storage unit 235, and displays the synchronization pattern arranged in the reproduction signal. Based on the start position of the separation pattern, the channel estimation calculation is performed using the reproduction signal of the separation pattern (step S407).

  Thereafter, the channel matrix estimation unit 233 uses a plurality of channel matrices obtained by channel estimation calculation from reproduced signals of separation patterns in a plurality of consecutive preambles with data sandwiched on a track, and uses the channel matrix estimation unit 233 within the section of the data. To estimate a variable channel matrix (step S408).

  Next, the signal separation calculation unit 234 reads the reproduction signal for one unit from the storage unit 235, and based on the channel matrix that is variable within the data interval estimated by the channel matrix estimation unit 233, The reproduction signal for each track is separated from the reproduction signal (step S410).

  Thereafter, the multi-track demodulator 240 decodes the data sequence from the reproduction signal separated for each track (step S411), and the restoration unit 260 concatenates the data for each track so that the reproduction data 3 is obtained. Is obtained (step S412).

  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.

  In the above embodiment, as shown in FIG. 6, a plurality of units 53 (1), 53 (2),..., 53 (E) are arranged in the track direction of the magnetic recording medium 2. For this reason, there are two possible data distribution methods in the magnetic recording / reproducing system using a single head.

  The first method is a method of filling data for each track. In FIG. 6, first, units 53 (1), 53 (2),. After the data is arranged in order, the data is arranged in the order of the units 53 (1), 53 (2),..., 53 (E) in the same manner for the next track # 2, and subsequently to the next track # 3. Similarly, the data is arranged in the order of the units 53 (1), 53 (2),..., 53 (E). In this case, since the reproduction signal for each track obtained from the reproduction signal for one unit at the time of reproduction becomes discontinuous data, each reproduction data is obtained after obtaining the reproduction signal for every unit track in the continuous recording / reproduction period. The original recording data is restored by linking them with a method according to the distribution method.

  In the second method, data is first filled in order from the head unit. First, the head unit 53 (1) of the track # 1, the head unit 53 (1) of the track # 2, and the track # 3 is arranged in the order of the first unit 53 (1), and then the second unit 53 (2) of track # 1, the second unit 53 (2) of track # 2, and the track # 3 Similarly, in the order of the second unit 53 (2), the third unit 53 (3) of the track # 1, the third unit 53 (3) of the track # 2, and the third unit 53 of the track # 3. This is a method of arranging data in the order of (3). According to this method, since the reproduction signal for each track obtained from the reproduction signal for one unit at the time of reproduction becomes continuous data, after obtaining the reproduction signal for every track of all the units in the continuous recording / reproduction period, By concatenating the reproduction data in the reproduction order, the original recording data is restored.

  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. 18 is a conceptual diagram of a data format recorded 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. Also in the helical scan system, a guard band 52 is disposed between unit-configured track rows 51 composed of track # 1, track # 2, and track # 3. The preamble 21 recorded in the track # 1, the track # 2, and the track # 3 may be the same as that shown in FIG. 8, for example. The present invention can also be applied to such a helical scan magnetic recording / reproducing method, and the configurations of the recording device 100 and the reproducing device 200 in the magnetic recording / reproducing method of the first embodiment can be employed.

  In FIG. 19, recording is performed on a recording medium by a double azimuth method and a helical scan method using a plurality of recording heads W-1, W-2, W-3, W-4, W-5, and W-6. It is a conceptual diagram of a data format.

  In this example, six recording heads W-1, W-2, W-3, W-4, W-5, and W-6 are used for recording and reproduction, respectively. Of these recording heads, the three consecutive recording heads W-1, W-2, and W-3 and the remaining three consecutive recording heads W-4, W-5, and W-6 are mutually connected to each other. The azimuth direction, which is the magnetization direction, is made different. That is, track # 1- # 3 and track # 4- # 6 have different azimuth directions. These tracks # 1 to # 6 form a unit configuration track row 51 including a plurality of units which are 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 FIG. 8, for example. The present invention can also be applied to such a magnetic recording / reproducing system of the double azimuth method and the helical scan method, and the configuration of the recording apparatus 100 and the reproducing apparatus 200 in the magnetic recording / reproducing system of the first embodiment is adopted. be able to.

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

It is a figure which shows the structure of the recording device in the magnetic recording / reproducing system of the 1st Embodiment of this invention. 3 is a flowchart showing an operation of unit recording by the recording apparatus of FIG. 1. It is a figure which shows the structure of the reproducing | regenerating apparatus in the magnetic recording / reproducing system of the 1st Embodiment of this invention. FIG. 4 is a diagram illustrating a configuration of a multitrack demodulator in the playback device of FIG. 3. 4 is a flowchart showing an operation of unit playback by the playback device of FIG. 3. It is a conceptual diagram of the data format on the magnetic recording medium with which recording was performed by the recording device of FIG. It is a figure which shows the example of the mode of the track | truck deviation of each reproducing head on the format shown in FIG. It is a figure which shows the structure of the preamble recorded on a magnetic recording medium. It is a figure which shows the specific example of the channel matrix estimation operation | movement by a channel matrix estimation part. It is a figure which shows the other specific example of the channel matrix estimation operation | movement by a channel matrix estimation part. It is a figure which shows another example of the data format which concerns on this invention. 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. 13 is a flowchart showing a unit recording operation by the recording apparatus of FIG. It is a figure which shows the structure of the recording device which is a modification of the recording device in the magnetic recording / reproducing system of 2nd Embodiment. 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 400 in the magnetic recording / reproducing system which is the 2nd Embodiment of this invention. FIG. 17 is a flowchart showing an operation of unit playback by the playback device of FIG. 16. FIG. It is a conceptual diagram of a data 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 data 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. FIG. 21 is a flowchart showing a unit recording operation by the recording apparatus of FIG. 20. 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.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Recording data 2 Magnetic recording medium 3 Reproduction data 21 Preamble 22 Data 31, 32, 33 Channel matrix 34, 35, 36 Separation pattern 53 Unit 100 Recording apparatus 110 Multitracking part 111 Data distributor 120 Multitrack recording encoding part 121 -1, 121-2, 121-3 Recording encoding unit 130 Multitrack preamble adding unit 131-1, 131-2, 131-3 Preamble adding unit 140 Multitrack recording unit 141-1, 141-2, 141-3 Output timing setting units 144-1, 144-2, 144-3 Recording compensation units 147-1, 147-2, 147-3 Recording amplifier 149 Storage unit 150 Recording head array 200 Playback device 210 Playback head array 220 Channel playback unit 221 -1, 221-2, 22 1-3 Playback Amplifiers 224-1, 224-2, 224-3 Gain Adjustment Units 225-1, 225-2, 225-3 A / D Converter 230 Signal Separation Processing Unit 231 Synchronization Signal Detector 232 Channel Estimation Calculation Unit 233 Channel matrix estimation unit 234 Signal separation calculation unit 235 Storage unit 240 Multitrack demodulation units 241-1, 241-2, 241-3 Equalizers 243-1, 243-2, 243-3 Detectors 244-1, 244- 2, 244-3 Sync signal detectors 245-1, 245-2, 245-3 Decoder 260 Restoration unit 261 Data combiner R-1, R-2, R-3 Reproducing head W-1, W-2, W-3 Recording head

Claims (21)

There are a plurality of tracks, and for each of the tracks, a positional relationship in the track width direction between the data, a reproducing head capable of reproducing a signal across the one or more tracks, and the plurality of tracks is shown. A preamble including a pattern necessary for detection is recorded, and the data of the plurality of tracks and the unit as a unit of signal processing for reproducing the data of the preamble include a plurality of the units in the track direction. An apparatus for reproducing the data from a recording medium continuously recorded on the recording medium,
Based on the reproduction signal of the pattern for each unit, 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;
A channel matrix estimator that estimates a variable channel matrix within a section of the data using a channel matrix obtained by the channel estimation calculator based on the reproduction signal of the pattern in the unit;
Signal separation for separating the reproduction signal of the data for each track from the reproduction signal of the data for one unit reproduced by the reproduction head, using the variable channel matrix estimated by the channel matrix estimation unit A playback device comprising: an arithmetic unit. The playback apparatus according to claim 1,
The channel matrix estimator is variable within a section of the data using a plurality of channel matrices obtained by the channel estimation calculator based on reproduction signals of the pattern in a plurality of consecutive units. A reproduction apparatus characterized by estimating a channel matrix. The playback apparatus according to claim 1,
The channel matrix estimation unit is configured to divide the sections of the data from a plurality of channel matrices respectively obtained by the channel estimation calculation unit based on reproduction signals of the pattern in the plurality of consecutive units. Estimate a plurality of channel matrices respectively corresponding to
The signal separation calculation unit uses the plurality of channel matrices obtained by the channel matrix estimation unit, from the reproduced signal of the data for the one unit reproduced by the reproducing head for each individual section. A reproduction apparatus for separating the reproduction signal of the data for each track. The playback apparatus according to claim 3, wherein
The channel matrix estimation unit is configured to apply linear interpolation to individual sections of the data from a plurality of channel matrices obtained by the channel estimation calculation unit based on reproduction signals of the pattern in a plurality of consecutive units. A reproduction apparatus characterized by estimating a plurality of corresponding channel matrices. The playback apparatus according to claim 1,
The channel matrix estimation unit is sandwiched by the preambles in the two units from two channel matrices obtained by the channel estimation calculation unit based on the reproduced signals of the patterns in the two consecutive units. A reproduction apparatus characterized by estimating a variable channel matrix within a section of data. The playback apparatus according to claim 1,
The channel matrix estimation unit is positioned behind both of the plurality of patterns from a plurality of channel matrices obtained by the channel estimation calculation unit based on reproduction signals of the patterns in the plurality of consecutive units. A reproduction apparatus characterized by estimating a variable channel matrix within a section of data to be transmitted. The playback apparatus according to claim 1,
2. A reproducing apparatus according to claim 1, wherein the pattern is a separation pattern composed of a signal having a recording wavelength equal to or greater than the minimum recording wavelength and disposed at a unique position for each track. The playback apparatus according to claim 1,
The reproducing apparatus, wherein the pattern is tracking servo information. The playback apparatus according to claim 1,
The signal separation calculation unit obtains a generalized inverse matrix of the variable channel matrix estimated by the channel matrix estimation unit, and the generalized inverse matrix and the data for the one unit reproduced by the reproduction head A reproduction apparatus for separating the reproduction signal of the data for each track from the reproduction signal. The playback apparatus according to claim 1,
The signal separation operation unit separates a reproduction signal of the data for each track by a MMSE (Minimum Mean Squared Error) method from the variable channel matrix estimated by the channel matrix estimation unit. Playback device. 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,
The reproducing apparatus is characterized in that the reproducing head is movable in the width direction of the track so that signals can be reproduced in different positional relations with respect to the plurality of tracks of one unit. There are a plurality of tracks, and for each of the tracks, a positional relationship in the track width direction between the data, a reproducing head capable of reproducing a signal across the one or more tracks, and the plurality of tracks is shown. A preamble including a pattern necessary for detection is recorded, and a plurality of units are arranged in the track direction as a unit that is a unit of signal processing for reproducing the data and the preamble of the plurality of tracks. A method for reproducing the data from a continuously recorded recording medium,
Calculating a channel matrix corresponding to the positional relationship in the track width direction during reproduction between the reproduction head and the plurality of tracks, based on the reproduction signal of the pattern for each unit;
A step of estimating a variable channel matrix within a section of the data by using a plurality of channel matrices respectively obtained in the channel matrix calculation step based on reproduction signals of the pattern in a plurality of consecutive units. When,
Separating the reproduction signal of the data for each track from the reproduction signal of the data for the unit reproduced by the reproduction head using the estimated variable channel matrix. A characteristic reproduction method. An apparatus for recording a plurality of tracks on a recording medium,
A multi-track recording encoding unit for encoding data to be recorded for each track;
Reproduction of a reproduction head capable of reproducing a signal across one or more of the tracks in the code string of the data for each of the tracks encoded by the multitrack recording encoding unit and the plurality of tracks A multi-track preamble adding unit for adding a preamble including a pattern necessary for detecting the positional relationship in the track width direction at the time;
The multi-track preamble adding unit sets the preamble and the data of the plurality of tracks as a unit that is a unit of signal processing for reproducing the data so that a plurality of the units are arranged in the track direction. A recording apparatus comprising: a multi-track recording unit that records data for each track to which the preamble is added to the recording medium by the recording head. 15. The recording apparatus according to claim 14, wherein
The multi-track preamble adding unit adds the preamble to the data other than the data recorded at the end of the track, and adds the preamble to the data recorded at the end of the track. A recording apparatus, wherein the preamble is added before and after the data. A method for recording a plurality of tracks on a recording medium,
Encoding data to be recorded for each track;
A position in the track width direction during reproduction of the reproduction head capable of reproducing a signal across one or more of the tracks and the plurality of tracks in the encoded code string of the data for each of the tracks. Adding a preamble containing the pattern necessary to detect the relationship;
The preamble and the data of the plurality of tracks as a unit that is a unit of signal processing for reproducing the data, and the preamble is added so that a plurality of the units are arranged in the track direction. Recording the data for each track on the recording medium by the recording head.   There are a plurality of tracks, and for each of the tracks, a positional relationship in the track width direction between the data, a reproducing head capable of reproducing a signal across the one or more tracks, and the plurality of tracks is shown. A preamble including a pattern necessary for detection, and the data of the plurality of tracks and the preamble are respectively continuous with the plurality of tracks as a unit of signal processing for reproducing the data. A data format characterized by being arranged. The data format according to claim 17, wherein
A data format, wherein the preamble is arranged before and after the data.   There are a plurality of tracks, and for each of the tracks, a positional relationship in the track width direction between the data, a reproducing head capable of reproducing a signal across the one or more tracks, and the plurality of tracks is shown. And a preamble including a pattern necessary for detection, and the data of the plurality of tracks and the preamble are continuously recorded in the track direction as a unit of signal processing for reproducing the data. Medium. The recording medium according to claim 19, wherein
The recording medium, wherein the preamble is recorded before and after the data code string. An apparatus for recording a plurality of tracks on a recording medium,
A multi-track recording encoding unit for encoding data to be recorded for each track;
Reproduction of a reproduction head capable of reproducing a signal across one or more of the tracks in the code string of the data for each of the tracks encoded by the multitrack recording encoding unit and the plurality of tracks A multi-track preamble adding unit for adding a preamble including a pattern necessary for detecting the positional relationship in the track width direction at the time;
The multi-track preamble adding unit sets the preamble and the data of the plurality of tracks as a unit that is a unit of signal processing for reproducing the data so that a plurality of the units are arranged in the track direction. A recording apparatus comprising: a multi-track recording unit that records data for each track to which the preamble is added to the recording medium by the recording head;
An apparatus for reproducing the data from the recording medium,
Based on the reproduction signal of the pattern for each unit, 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;
A channel matrix estimator that estimates a variable channel matrix within a section of the data using a channel matrix obtained by the channel estimation calculator based on the reproduction signal of the pattern in the unit;
Signal separation for separating the reproduction signal of the data for each track from the reproduction signal of the data for one unit reproduced by the reproduction head, using the variable channel matrix estimated by the channel matrix estimation unit A recording / reproducing apparatus comprising: a computing unit;

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