JP2008293558A - Magnetic recording and reproducing device, recording apparatus, recording method, and magnetic recording medium - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To suitably form a guard band to be a non-signal area for preventing interference between tracks in adjacent units between the units to be one unit of signal processing. <P>SOLUTION: In a magnetic recording and reproducing system wherein a plurality of tracks to be one unit of signal processing for detecting data are recorded in a magnetic recording medium by using a recording head, a plurality of signals to the plurality of tracks are reproduced in different positional relations to the plurality of tracks by using a reproduction head capable of reproducing signals over the plurality of tracks of the magnetic recording medium and reproduction signals for every track are generated by collecting the reproduction signals in one unit to perform signal processing, the guard band is positively formed by writing an erasure signal in the area between the adjacent units by using an erasing head E1. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a magnetic recording / reproducing apparatus, a recording apparatus, a recording method, and a magnetic recording apparatus in which a plurality of tracks are recorded on a magnetic recording medium by one or a plurality of recording heads and a signal is reproduced from the plurality of tracks by one or a plurality of reproducing heads. The present invention relates to 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.

  Accordingly, the present inventors record a plurality of tracks, which are a unit of signal processing for data detection, on a magnetic recording medium by a recording head, and reproduce a signal across the plurality of tracks of the magnetic recording medium. With a playback head that can handle multiple tracks, the signals for multiple tracks are played back in multiple different positions with respect to multiple tracks. A method of generating was 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.

  By the way, in the case of adopting the same method, as one of technical problems for obtaining a more stable reproduction signal, there is an installation of an appropriate guard band.

  That is, in the above magnetic recording / reproducing method, one unit of signal processing is recorded as a plurality of tracks. Hereinafter, one unit of this signal processing is referred to as a “unit”. As shown in FIG. 18, when recording is performed over a plurality of units 51 (units # 1- # s), a non-signal area is guard band 52 between units 51 so that tracks between adjacent units 51 do not interfere with each other. It is necessary to provide as. For this reason, a method capable of stably providing an appropriate guard band 52 has been demanded.

  In view of such circumstances, the present invention can stably secure an appropriate guard band between adjacent units because one unit of signal processing is constituted by a plurality of tracks, and prevents interference between adjacent units of tracks. Thus, an object of the present invention is to provide a magnetic recording / reproducing apparatus, a recording apparatus, a recording method, and a magnetic recording medium that can perform good recording / reproducing.

  In order to solve the above problems, a magnetic recording / reproducing apparatus according to the present invention includes a recording unit that records a plurality of tracks as a unit of signal processing for data detection on a magnetic recording medium by a recording head; A signal erasure unit that creates a no-signal area as a guard band for separating the plurality of tracks by a erasing head on the recording medium, and a signal can be reproduced across the plurality of tracks of the magnetic recording medium A reproduction head reproduces a plurality of signals for the plurality of tracks with different positional relations with respect to the plurality of tracks, collects these reproduction signals into the unit, and performs signal processing, thereby reproducing each of the tracks. And a reproducing unit for generating a signal.

  According to the present invention, an appropriate guard band can be created by creating a no-signal area for separating a plurality of tracks as a guard band using an erasing head on a magnetic recording medium, and between adjacent units. Thus, it is possible to perform good recording and reproduction by preventing interference between the tracks.

  The signal erasing unit may create two guard bands for each unit of the signal processing. As a result, the degree of freedom in selecting the width of the guard band is improved and a wider guard band can be created as compared with the case of using one erasing head.

  The erasing head may be a recording head for magnetic recording, and the signal erasing unit may include an erasing signal generating unit that supplies an erasing signal to the erasing head. As a result, the signal erasing unit for creating the guard band can be realized with a simple configuration.

  The erasure signal generator may generate a repetitive signal having a recording wavelength equal to or smaller than the minimum recording wavelength as the erasure signal. Thereby, a non-signal area can be reliably created as a guard band in the magnetic recording medium.

  The erase signal generator may generate a direct current signal as the erase signal. This also makes it possible to reliably create a no-signal area as a guard band on the magnetic recording medium.

  A permanent magnet can be used for the erasing head. As a result, the signal erasing unit for creating the guard band can be realized with a simpler configuration.

  The reproduction unit obtains channel estimation information corresponding to position information of the reproduction head with respect to the plurality of tracks by the signal processing, and the channel estimation information and the plurality of tracks are reproduced with different positional relationships. A reproduction signal for each track may be obtained based on the signal.

  The recording unit generates a signal having a recording wavelength equal to or greater than the minimum recording wavelength at a unique position for each track so that the reproducing unit can generate position information of the reproducing head for the plurality of tracks. Recording as a separation pattern, and the reproduction unit may obtain the channel estimation information by the signal processing based on the reproduction signal of the separation pattern.

  The recording unit may record the plurality of tracks by a plurality of the recording heads, and the reproducing unit may generate a plurality of reproduction signals for the plurality of tracks by the plurality of reproducing heads.

  According to the present invention, since one unit of signal processing is composed of a plurality of tracks, it is possible to stably secure an appropriate guard band between adjacent units, and to prevent interference between adjacent units of the tracks. Recording and reproduction can be performed.

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

(First embodiment)
First, a first embodiment of the present invention will be described. The present embodiment relates to a magnetic recording / reproducing apparatus in which a erasing head for creating a guard band is provided in a recording head array.

  FIG. 1 is a diagram showing a configuration of a recording apparatus 100 which is a recording unit in the magnetic recording / reproducing apparatus 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 recording heads W1, W2, and the like. A recording head array 150 having W3 and an erasing head E1 and a signal erasing unit 160 for creating a guard band on the magnetic recording medium 2 using the erasing head E1 are provided.

  The multitrack unit 110 includes a data distributor 111 that distributes the recording data 1 to the number of recording heads W1, W2, and W3 (M = 3) provided in the recording head array 150 for multitracking. The

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

  The multitrack preamble adding unit 130 includes M preamble adding units 131-1, 131-2, and 131-3 that add a preamble to encoded recording data.

  The multi-track recording unit 140 includes M output timing setting units 141-1, 141-2, and 141-3 that give desired timing to the recording data to which the preamble is added, and M recording compensations that perform recording compensation processing. Sections 144-1, 144-2, 144-3, and M recording amplifiers 147-1, 147-2, which drive individual recording heads W1, W2, W3 based on the recording data after the recording compensation processing, 147-3.

  The signal erasing unit 160 includes an erasing head E1 provided in the recording head array 150, an erasing signal generation unit 170, an output timing setting unit 180, and a recording amplifier 190.

  The erase signal generator 170 generates a predetermined erase signal. The output timing setting unit 180 gives a predetermined timing to the output of the erase signal generated from the erase signal generation unit 170 and outputs it to the recording amplifier 190. The recording amplifier 190 converts the voltage into a current and outputs it to the erasing head E1 to drive the erasing head E1.

  In this recording apparatus 100, first, as shown in FIG. 2, the input recording data 1 is received by the multitracking unit 110 in the number of recording heads W1, W2, and W3 (M = 3) (for each track). Data) (step S11). Each distributed data is encoded into a code word string in consideration of recording / reproduction 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. It becomes. At this time, information necessary for data demodulation, such as a demodulation synchronization pattern, is also added to the codeword string (step S12).

  Next, a preamble code is given to the predetermined position of each generated codeword string by the preamble adding units 131-1, 131-2, 131-3 of the multitrack preamble adding unit 130, and the recording code string Is obtained (step S13). The preamble code is used for separating each reproduction signal read by each reproduction head into a signal for each track by predetermined signal processing as a processing unit, for automatic gain adjustment and / or bit synchronization detection. In consideration of the code word string rules generated by the recording encoding units 121-1, 121-2, and 121-3 of the multitrack recording encoding unit 120, for example, the minimum recording It is created by a signal having a recording wavelength equal to or longer than the wavelength. A sync signal pattern used for detecting the position of the separation pattern is also arranged before the separation pattern.

  Further, 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 multi-track recording unit 140, and then the recording compensation unit 144-1. 144-2 and 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 voltage to current by the recording amplifiers 147-1, 147-2, and 147-3 and sent to the recording heads W1, W2, and W3, and the recording heads W1, W2, and W3. Is recorded on the magnetic recording medium 2 (step S14). The azimuth directions of the plurality of tracks recorded on the magnetic recording medium 2 by the recording heads W1, W2, and W3 are the same.

  On the other hand, an erase signal in accordance with the erase method is output from the erase signal generator 170, and the erase signal is given an appropriate timing by the output timing setting unit 180, and is converted from voltage to current by the recording amplifier 190 to be erase head. Sent to E1. As a result, when three tracks for one unit are recorded on the magnetic recording medium 2 by the recording heads W1, W2, and W3, an erasing signal is written by the erasing head E1 to create a guard band.

  FIG. 3 is a diagram showing a method for creating a guard band in the recording apparatus 100 described above.

  As shown in the figure, the recording head array 150 includes three recording heads W1, W2,. W3 and one erasing head E1 are provided. The recording head array 150 is movable in the track width direction. In FIG. 3, for convenience of explanation, the recording head array 150 is shown to be located at two different positions in the track longitudinal direction, but the recording head array 150 is fixed in the track direction.

  The erasing head E1 includes, for example, recording heads W1, W2,. A recording head similar to W3 can be used. In this case, as an erasing method, AC erasure with magnetization reversal using a repetitive signal having a recording wavelength equal to or shorter than the minimum recording wavelength (1T) used in the magnetic recording system, and a DC erasing signal are used. DC erasing without magnetization reversal is employed.

  The creation of the guard band using the erasing head E1 is performed as follows, for example.

  When recording is started by the recording head array 150, first, the tape-shaped magnetic recording medium 2 moves in the direction of the arrow 19. At this time, the position of the recording head array 150 in the head width direction is P1. As a result, the three recording heads W1, W2,. The tracks 12, 13, and 14 for one unit are recorded by W3, and the erase signal is recorded by the erase head E1 to create the guard band 11.

  When the magnetic recording medium 2 has completely moved in the direction of the arrow 19, the recording head array 150 is moved a fixed distance in the head width direction and stops at the position P2. Thereafter, the magnetic recording medium 2 moves in the direction of the arrow 20 on the contrary. As a result, the tracks 16, 17, and 18 for the next unit on the magnetic recording medium 2 are transferred to the three recording heads W1, W2,. While being recorded by W3, a guard band 15 is created by the erasing head E1. The above operation is repeated a certain number of times in the tape width direction. As a result, the guard bands 11 and 15 are regularly created every three tracks.

  Here, the guard band width can be adjusted by adjusting the movement distance of the recording head array 150 once in the track width direction.

  FIG. 4 is a diagram showing a configuration of a modified example of the recording apparatus 100 described above, and shows a case where a permanent magnet 152 is used as the erasing head E1 instead of the recording bed. In this case, of course, the erase signal generator 170 for generating the card band, the output timing setting unit 180, and the recording amplifier 190 are unnecessary, and the permanent magnet 152 is simply arranged at an appropriate position of the recording head array 150. Good. The erasing method using the permanent magnet 152 is DC erasing without magnetization reversal in the track direction due to the property of the permanent magnet.

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

  FIG. 5 is a block diagram showing the configuration of the playback apparatus 200.

  As shown in the figure, the reproducing apparatus 200 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 N (for example, three) reproducing heads R1, R2, and R3 that read signals from each track recorded on the magnetic recording medium 2.

  The channel reproduction unit 220 includes N reproduction amplifiers 221-1, 221-2, and 221-3 that amplify signals reproduced by the N reproduction heads R1, R2, and R3 mounted on the reproduction head array 210. AGC 224-1, 224-2, 224-3 for controlling the gain so that the amplitude levels of the outputs of the N reproduction amplifiers 221-1, 221-2, and 221-3 become predetermined values, and AGC 224-1 A / D converters 225-1, 225-2, and 225-3 for quantizing the outputs of 224-2 and 224-3 into digital values having a predetermined bit width. 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 AGCs 224-1, 224-2, and 224-3 may be installed at the subsequent stage of the A / D converters 225-1, 225-2, and 225-3, and the gain may be controlled after quantization.

  The signal separation processing unit 230 includes a synchronization signal detector 231 that detects a synchronization pattern for knowing the start position of the separation pattern from the outputs of the A / D converters 225-1, 225-2, and 225-3, and a synchronization signal. By identifying the start position of the separation pattern based on the synchronization pattern detected by the detector 231 and performing channel estimation calculation and signal separation calculation using the separation pattern, a plurality of reproducing heads R1, R2, R3 And a signal separation calculation unit 236 that separates the reproduction signal for each track from the reproduction signal for one unit reproduced by the above.

  The multi-track demodulation unit 240 includes M equalizers 241-1, 241-2, and 241-3 that perform equalization processing on the reproduction signal separated for each track, and an equalizer 241-1. M PLLs 242-1, 242-2, and 242-3 that perform bit synchronization from outputs of 241-2 and 241-3, and bit synchronization signals generated by the PLLs 242-1, 242-2, and 242-3 are used. For example, M detectors 243-1, 243-2, 243-3 such as a Viterbi detector, and detectors 243-1, 243- are generated by binarizing the reproduction signal for each track. M post-synchronization signal detectors 244-1, 244-2, and 244-3 for detecting a sync signal on the codeword string from the binarized reproduction signal that is the output of 2,243-3, Synchronization signal detectors 244-1 and 244-2 , 244-3, M decoders 245-1, 245-2, and 245-3 that identify the data start position and decode the data string from the codeword string by the synchronization signal of the data area detected by 244-3 Prepare.

  The restoration unit 260 is a data combiner that restores the reproduction data 3 by connecting the data of each track output from the M decoders 245-1, 245-2, and 245-3 by the reverse operation to that at the time of recording. 261.

  In the reproducing apparatus 200, as shown in FIG. 6, first, a signal is reproduced from each track of the magnetic recording medium 2 by N (for example, three) reproducing heads R1, R2, and R3 (step S21). Next, after the amplitude levels of the outputs of the reproduction amplifiers 221-1, 221-2, and 221-3 are adjusted by the AGCs 224-1, 224-2, and 224-3, the AGCs 224-1, 224-2, The output of 224-3 is converted into a digital value by the A / D converters 225-1, 225-2, and 225-3 and is output to the synchronization signal detector 231 (step S22). The synchronization signal detector 231 detects a synchronization pattern for knowing the start position of the separation pattern from the outputs of the A / D converters 225-1, 225-2, and 225-3 (step S23). The signal separation calculation unit 236 specifies the start position of the separation pattern arranged in each reproduction signal based on the detected synchronization pattern, and performs a predetermined channel estimation calculation using the separation pattern (step S24). . Here, the channel estimation calculation is a process of calculating channel estimation information corresponding to reproduction head position information for a plurality of tracks. Further, the signal separation calculation unit 236 performs a process of generating a reproduction signal for each track from the channel estimation information and the reproduction signal for one unit (step S25).

  Thereafter, the equalizer 241-1, 241-2, 241-3 of the multitrack demodulator 240 performs an equalization process on the reproduction signal separated for each track, and the PLL 242-1. , 242-2, and 242-3, the binarization of the reproduction signal for each track is performed by the detectors 243-1, 243-2, and 243-3 using the bit synchronization signal generated by each track. Each codeword string is generated. Further, the synchronization signal detectors 244-1, 244-2, and 244-3 in the subsequent stage detect the synchronization signals on the code word string for each track, and the decoders 245-1, 245-2, and 245-3 detect them. The data string is decoded from the code word string for each track (step S26). Then, the reconstruction unit 260 concatenates the data for each track to obtain reproduction data (step S27).

  As described above, according to this embodiment, an appropriate guard band can be created by the erasing head E1 provided in the recording head array 150, and recording / reproduction can be performed while preventing interference between adjacent units. Can be performed satisfactorily.

(Second Embodiment)
Next, a second embodiment of the present invention will be described. The present embodiment relates to a magnetic recording / reproducing apparatus in which two erasing heads are provided in a recording head array. Note that the configuration of the reproducing apparatus in the magnetic recording / reproducing apparatus of the present embodiment is the same as that of the reproducing apparatus 200 of the first embodiment.

  FIG. 7 is a diagram showing a configuration of a recording apparatus 300 that is a recording unit in the magnetic recording / reproducing apparatus according to the second embodiment of the present invention, and shows a configuration when a recording head is used as the erasing head.

  As shown in the figure, the recording apparatus 300 includes a multitracking unit 110, a multitrack recording encoding unit 120, a multitrack preamble adding unit 130, a multitrack recording unit 140, recording heads W1, W2, and the like. A recording head array 150 having W3 and two erasing heads E1 and E2 and a signal erasing unit 160 for creating a guard band using the two erasing heads E1 and E2 provided on the magnetic recording medium 2 are provided.

  Since the configurations and operations of the multitracking unit 110, the multitrack recording encoding unit 120, the multitrack preamble adding unit 130, and the multitrack recording unit 140 are the same as those in the first embodiment, description thereof will be omitted.

  The signal erasing unit 160 includes two erasing heads E1 and E2 provided in the recording head array 150, erasing signal generating units 170 and 171 provided for each of the erasing heads E1 and E2, an output timing setting unit 180, 181 and recording amplifiers 190 and 191.

  In this recording apparatus 300, predetermined erase signals are output from the two erase signal generators 170, 171, and the respective erase signals are given appropriate timings by the output timing setting units 180, 181, and then the recording amplifier 190. , 191 is converted from voltage to current and sent to the corresponding erase heads E1, E2. As a result, three tracks for one unit are recorded on the magnetic recording medium 2 by the recording heads W1, W2, and W3, and at the same time, an erasing signal is written by the two erasing heads E1 and E2 to create a guard band. Is done.

  FIG. 8 is a diagram showing a method for creating a guard band in the recording apparatus 300 described above.

  As shown in the figure, the recording head array 150 includes three recording heads W1, W2,. One erasing head E1, E2 is arranged on each side of W3. The recording head array 150 is movable in the track width direction. In FIG. 8, for convenience of explanation, the recording head array 150 is shown to be located at two different positions in the track direction, but the recording head array 150 is fixed in the track direction.

  Each of the erasing heads E1, E2 includes, for example, recording heads W1, W2,. A recording head similar to W3 can be used. In this case, as an erasing method, AC erasure with magnetization reversal using a repetitive signal having a recording wavelength equal to or shorter than the minimum recording wavelength (1T) used in the magnetic recording system, and a DC erasing signal are used. DC erasing without magnetization reversal is employed.

  Creation of a guard band using these two erasing heads E1 and E2 is performed as follows, for example.

  When recording is started by the recording head array 150, first, the tape-shaped magnetic recording medium 2 moves in the direction of the arrow 19. At this time, the position of the recording head array 150 in the head width direction is P1. As a result, the three recording heads W1, W2,. By W3, tracks 22, 23, and 24 for one unit are recorded on the magnetic recording medium 2, and erase signals are recorded by two erase heads E1 and E2 on both outer sides of the unit in the track width direction. Guard bands 21 and 25 are created.

  When the magnetic recording medium 2 has completely moved in the direction of the arrow 19, the recording head array 150 is moved a fixed distance in the head width direction and stops at the position P2. Thereafter, the magnetic recording medium 2 moves in the direction of the arrow 20 on the contrary. As a result, the tracks 27, 28, and 29 for the next unit on the magnetic recording medium 2 are transferred to the three recording heads W 1, W 2. Recording is performed by W3, and two guard bands 26 and 30 are created by the two erasing heads E1 and E2. The above operation is repeated a certain number of times in the tape width direction. As a result, the guard bands 21, 26, 30 are regularly created every three tracks.

  Here, the guard band width can be adjusted by adjusting the movement distance of the recording head array 150 once in the track width direction.

  As described above, according to this embodiment, an appropriate guard band can be provided by the two erasing heads E1 and E2, and recording and reproduction can be performed satisfactorily by preventing interference between adjacent units. Is possible. In addition, by creating a guard band with two erasing heads E1 and E2, the degree of freedom in selecting the width of the guard band can be improved and a wider guard band can be created as compared with the case where one erasing head is used.

  FIG. 9 is a diagram showing a configuration of a modified example of the recording apparatus 300 described above, and shows a case where permanent magnets 152 and 153 are used as the erasing heads E1 and E2 instead of the recording head. In this case, naturally, the erasure signal generators 170 and 171, the output timing setting units 180 and 181, and the recording amplifiers 190 and 191 in FIG. 7 are not necessary, and appropriate positions at both ends of the recording head array 150. The permanent magnets 152 and 153 may be simply arranged. The erasing method using the permanent magnets 152 and 153 is DC erasing without magnetization reversal in the track direction due to the property of the permanent magnet.

  In the first and second embodiments described above, the linear recording method (method in which recording tracks are created in the longitudinal direction of the tape) is shown, but the helical scan method (tape length). The present invention can be similarly applied to a method in which a recording track is created obliquely rather than in a direction.

(Third embodiment)
Next, a third embodiment of the present invention will be described. The present embodiment relates to a magnetic recording / reproducing apparatus in which a plurality of recording heads and an erasing head are provided independently for each head in a helical scan recording system. The configuration of the reproducing apparatus in the magnetic recording / reproducing apparatus of this embodiment is the same as that of the reproducing apparatus 200 of the first embodiment.

  FIG. 10 is a diagram showing a configuration of a recording apparatus 400 as a recording unit in the magnetic recording / reproducing apparatus according to the third embodiment of the present invention, and shows a configuration when a recording head is used as the erasing head.

  As shown in the figure, the recording apparatus 400 includes a multitracking unit 110, a multitrack recording encoding unit 120, a multitrack preamble adding unit 130, a multitrack recording unit 140, three recording heads W1, W2 and W3, and a signal erasing unit 160 that creates a guard band using the erasing head E1.

  Since the configurations and operations of the multitracking unit 110, the multitrack recording encoding unit 120, the multitrack preamble adding unit 130, and the multitrack recording unit 140 are the same as those in the first embodiment, description thereof will be omitted.

  The signal erasing unit 160 includes an erasing head E1, an erasing signal generating unit 170, an output timing setting unit 180, and a recording amplifier 190.

  In this recording apparatus 400, an erasing signal in accordance with a predetermined erasing method is output from the erasing signal generating unit 170, and the erasing signal is given an appropriate timing in the helical scan recording method by the output timing setting unit 180. The recording amplifier 190 converts the voltage into a current and sends it to the erasing head E1, and the erasing signal is written by the erasing head E1 to create a guard band.

  FIG. 11 is a diagram showing the arrangement of the recording head and the erasing head in the recording apparatus 400 of the helical scan recording method.

  In the helical scan recording method, the head is mounted on the rotating drum 40 that rotates. Here, W1, W2, and W3 are recording heads, R1, R2, and R3 are reproducing heads, and E1 is an erasing head. The recording heads W1, W2, W3 and the erasing head E1 are respectively disposed on the rotating drum 40 rotating in the direction of the arrow 41 in the drawing, for example, at rotation angle positions at intervals of 90 degrees. Further, the magnetic recording medium 2 is moved in the direction of the arrow 42 in the drawing (from left to right).

  FIG. 12 is a diagram showing a method for creating a guard band by the helical scan recording type recording apparatus 400 having the head arrangement shown in FIG.

  The card band 31 and the tracks 32, 33, and 34 are recorded on the magnetic recording medium 2 by the first scanning of the erasing head E1 and the recording heads W1, W2, and W3, and the card band is recorded on the magnetic recording medium 2 by the second scanning. 35 and tracks 36, 37, and 38 are recorded.

  For example, the recording heads W1, W2,. A recording head similar to W3 can be used. In this case, as an erasing method, AC erasure with magnetization reversal using a repetitive signal having a recording wavelength equal to or shorter than the minimum recording wavelength (1T) used in the magnetic recording system, and a DC erasing signal are used. DC erasing without magnetization reversal is employed.

  The creation of the guard band using the erasing head E1 is performed as follows, for example.

  When recording is started, the magnetic recording medium 2 has moved in the direction of the arrow 43 in the figure. During the movement of the magnetic recording medium 2, scanning in the direction of the arrow 44 in the figure is started in the order of the erasing head E1, the recording head W1, the recording head W2, and the recording head W3. A card band 31, a track 32, a track 33, and a track 34 are recorded.

  Then, when the rotary drum 40 rotates exactly once from the start of recording, the erasing head E1 is positioned next to the recording head W3, and as before, the erasing head E1, the recording head W1, the recording head W2, and the recording head. By starting scanning in the direction of arrow 44 in the figure in the order of W3, the card band 35, the track 36, the track 37, and the track 38 are recorded on the magnetic recording medium 2.

  Thereafter, similarly, every time the rotating drum 40 rotates once, the creation of the guard band by the erasing head E1 and the recording of the tracks by the recording heads W1, W2, and W3 are repeated until the end point in the longitudinal direction of the magnetic recording medium 2. . As a result, the guard bands 31 and 35 are regularly created every three tracks.

  Here, the position of the next recording head W1 in the rotation direction of the rotary drum 40 with respect to the position of the erasing head E1 is moved closer to the erasing head E1 side, or other appropriate methods are used, thereby providing a guard band. It is possible to adjust the width.

  As described above, according to this embodiment, in the helical scan recording method, an appropriate guard band can be provided by the erasing head E1, and the recording / reproduction can be improved by preventing the interference between adjacent units. It becomes possible to do.

  FIG. 13 is a diagram showing a configuration of a modified example of the recording apparatus 400 described above, and shows a configuration when a permanent magnet 152 is used as the erasing head E1 instead of the recording head. In this case, of course, the erase signal generator 170, the output timing setting unit 180, and the recording amplifier 190 are not necessary.

(Fourth embodiment)
Next, a fourth embodiment of the present invention will be described. The present embodiment relates to a magnetic recording / reproducing apparatus in which a recording head array having three recording heads and one erasing head are provided independently in a helical scan recording system. The configuration of the reproducing apparatus in the magnetic recording / reproducing apparatus of this embodiment is the same as that of the reproducing apparatus 200 of the first embodiment.

  FIG. 14 is a diagram showing a configuration of a recording apparatus 500 that is a recording unit in a magnetic recording / reproducing apparatus according to a fourth embodiment of the present invention, and shows a configuration in which a recording head is used as an erasing head.

  As shown in the figure, the recording apparatus 500 includes a multitracking unit 110, a multitrack recording encoding unit 120, a multitrack preamble adding unit 130, a multitrack recording unit 140, three recording heads W1, A recording head array 150 having W2 and W3 and a signal erasing unit 160 that creates a guard band using the erasing head E1 are provided.

  Since the configurations and operations of the multitracking unit 110, the multitrack recording encoding unit 120, the multitrack preamble adding unit 130, and the multitrack recording unit 140 are the same as those in the first embodiment, description thereof will be omitted.

  The signal erasing unit 160 includes an erasing head E1, an erasing signal generating unit 170, an output timing setting unit 180, and a recording amplifier 190.

  In this recording apparatus 500, an erasing signal in accordance with a predetermined erasing method is output from the erasing signal generation unit 170, and the erasing signal is given an appropriate timing in the helical scan recording method by the output timing setting unit 180. The recording amplifier 190 converts the voltage into a current and sends it to the erasing head E1, and the erasing signal is written by the erasing head E1 to create a guard band.

  FIG. 15 is a diagram showing the arrangement of recording heads and erasing heads in the above-described helical scan recording type recording apparatus 500.

  In the helical scan recording method, the head is mounted on the rotating drum 40 that rotates. Here, WA1 is a recording head array having a plurality of recording heads W1, W2 and W3, RA1 is a reproducing head array having a plurality of reproducing heads, and E1 is an erasing head. The recording head array WA1 and the erasing head E1 are respectively arranged on the rotating drum 40 rotating in the direction of the arrow 41 in the drawing, for example, at rotation angle positions at intervals of 180 degrees. The magnetic recording medium 2 is moved in the direction of the arrow 42 in the figure (from left to right).

  FIG. 16 is a diagram showing a method of creating a guard band by the helical scan recording type recording apparatus 500 having the head arrangement shown in FIG.

  The card band 31 and the tracks 32, 33, and 34 are recorded on the magnetic recording medium 2 by the first scanning of the recording heads W1, W2, and W3 fixed to the erasing head E1 and the recording head array WA1, and the second scanning is performed. The card band 35 and tracks 36, 37, and 38 are recorded on the magnetic recording medium 2.

  The erasing head E1 includes, for example, recording heads W1, W2,. A recording head similar to W3 can be used. In this case, as an erasing method, AC erasure with magnetization reversal using a repetitive signal having a recording wavelength equal to or shorter than the minimum recording wavelength (1T) used in the magnetic recording system, and a DC erasing signal are used. DC erasing without magnetization reversal is employed.

  The creation of the guard band using the erasing head E1 is performed as follows, for example.

  When recording is started, the magnetic recording medium 2 has moved in the direction of the arrow 43 in the figure. During the movement of the magnetic recording medium 2, scanning in the direction of the arrow 44 in the figure is started in the order of the erasing head E1, the recording head W1, the recording head W2, and the recording head W3. A card band 31, a track 32, a track 33, and a track 34 are recorded.

  Then, when the rotary drum 40 rotates exactly once from the start of recording, the erasing head E1 is positioned next to the recording head W3, and as before, the erasing head E1, the recording head W1, the recording head W2, and the recording head. By starting scanning in the direction of arrow 44 in the figure in the order of W3, the card band 35, the track 36, the track 37, and the track 38 are recorded on the magnetic recording medium 2.

  Similarly thereafter, every time the rotary drum 40 makes one revolution, the creation of the guard band by the erasing head E1 and the recording of the tracks by the recording heads W1, W2, and W3 are repeated until the end point in the longitudinal direction of the magnetic recording medium 2. . As a result, the guard bands 31 and 35 are regularly created every three tracks.

  Here, the position of the next recording head W1 in the rotation direction of the rotary drum 40 with respect to the position of the erasing head E1 is moved closer to the erasing head E1 side, or other appropriate methods are used, thereby providing a guard band. It is possible to adjust the width.

  As described above, according to this embodiment, in the helical scan recording method, an appropriate guard band can be provided by the erasing head E1, and the recording / reproduction can be improved by preventing the interference between adjacent units. It becomes possible to do.

  In the recording apparatus 500 according to the fourth embodiment, a permanent magnet may be used as the erasing head E1 instead of the recording head.

  The description so far has been based on the premise that the guard band is actively created by the erasing head. However, for example, when using an unwritten medium that has never been used, the erasing is performed. Even without using a head, a guard band can be created by recording a recording signal at a predetermined interval, but even in this case, a guard band can be created actively using an erasing head. Good.

  FIG. 17 is a diagram showing a modified row of the arrangement of the recording head and the erasing head in the helical scan recording type recording apparatus 400 of the third embodiment.

  In this modified example, four sets of one erasing head and three recording heads are provided on the rotating drum 40, and a recording pattern of one erasing track + three recording tracks per rotation of the rotating drum 40. Four sets are created. That is, according to this method, the first unit and the guard band are recorded by the erasing head E1 and the three recording heads W1, W2, and W3, and the next erasing head E2 and the next three recording heads W4, W5, and W3. The second unit and the guard band are recorded at W6, the third unit and the guard band are recorded at the next erasing head E3 and the next three recording heads W7, W8, and W9. A fourth unit and a guard band are recorded by the next three recording heads W10, W11, and W12. This enables higher density recording.

  Although the magnetic recording / reproducing apparatus has been described as an embodiment according to the present invention, it goes without saying that the present invention can be applied to a recording-only recording apparatus that performs the same multitrack recording using a recording head on a magnetic recording medium. Yes.

  The present invention is not limited only to the above-described embodiment, and it is needless to say that various updates can be added without departing from the gist of the present invention.

1 is a diagram illustrating a configuration of a recording apparatus that is a recording unit in a magnetic recording / reproducing apparatus according to a first embodiment of the present invention. FIG. 3 is a flowchart showing a recording operation by the recording apparatus of FIG. 1. It is a figure which shows the preparation method of the guard band in the recording device of FIG. It is a figure which shows the structure of the modification of the recording device of FIG. It is a figure which shows the structure of the reproducing | regenerating apparatus in the magnetic recording / reproducing apparatus concerning the 1st Embodiment of this invention. 6 is a flowchart showing a reproduction operation by the reproduction apparatus of FIG. It is a figure which shows the structure of the recording device which is a recording part in the magnetic recording / reproducing apparatus of the 2nd Embodiment of this invention. It is the figure shown about the production method of the guard band in the recording device of FIG. It is a figure which shows the structure of the modification of the recording device of FIG. It is a figure which shows the structure of the recording device which is a recording part in the magnetic recording / reproducing apparatus of the 3rd Embodiment of this invention. FIG. 11 is a diagram illustrating an arrangement of recording heads and erasing heads in the recording apparatus of FIG. 10. It is the figure shown about the production method of the guard band by the recording device of FIG. It is a figure which shows the structure of the modification of the recording device of FIG. It is a figure which shows the structure of the recording device which is a recording part in the magnetic recording / reproducing apparatus of the 4th Embodiment of this invention. FIG. 15 is a diagram illustrating an arrangement of recording heads and erasing heads in the recording apparatus of FIG. 14. It is the figure shown about the production method of the guard band by the recording device of FIG. It is a figure which shows the deformation | transformation row | line | column of arrangement | positioning of the recording head and the erasing head in the recording apparatus of the helical scan recording system of 3rd Embodiment. It is a figure which shows the guard band arrange | positioned between the unit which is a unit of signal processing, and this unit.

Explanation of symbols

2 Magnetic recording media 11, 15 Guard band 12, 13, 14, 16, 17, 18 Track 100 Recording device 110 Multitracking unit 120 Multitrack recording encoding unit 130 Multitrack preamble adding unit 140 Multitrack recording unit 152 Permanent magnet 160 signal erasure unit 170 erasure signal generation unit 180 output timing setting unit 190 recording amplifier 200 reproduction device 210 reproduction head array 220 channel reproduction unit 230 signal separation processing unit 240 multitrack demodulation unit 260 restoration unit E1 erasure head W1, W2, W3 recording head

Claims (18)

A recording unit for recording a plurality of tracks, which is a unit of signal processing for data detection, on a magnetic recording medium by a recording head;
A signal erasing unit that creates a no-signal area as a guard band for separating the plurality of tracks by an erasing head on the magnetic recording medium;
A reproduction head capable of reproducing a signal across the plurality of tracks of the magnetic recording medium reproduces a plurality of signals for the plurality of tracks with different positional relationships with respect to the plurality of tracks, and these reproduction signals A magnetic recording / reproducing apparatus comprising: a reproducing unit that generates a reproduction signal for each track by performing signal processing on the unit as a unit. The magnetic recording / reproducing apparatus according to claim 1,
The signal erasing unit creates two guard bands for each unit of the signal processing. The magnetic recording / reproducing apparatus according to claim 1,
The erasing head is a recording head for magnetic recording;
The magnetic recording / reproducing apparatus, wherein the signal erasing unit includes an erasing signal generating unit for supplying an erasing signal to the erasing head. The magnetic recording / reproducing apparatus according to claim 3,
The magnetic recording / reproducing apparatus characterized in that the erasure signal generator generates a repetitive signal having a recording wavelength equal to or shorter than the shortest recording wavelength as the erasure signal. The magnetic recording / reproducing apparatus according to claim 3,
The magnetic recording / reproducing apparatus according to claim 1, wherein the erase signal generator generates a direct current signal as the erase signal. The magnetic recording / reproducing apparatus according to claim 1,
The magnetic recording / reproducing apparatus, wherein the erasing head is made of a permanent magnet. The magnetic recording / reproducing apparatus according to claim 1,
The reproduction unit obtains channel estimation information corresponding to position information of the reproduction head with respect to the plurality of tracks by the signal processing, and the channel estimation information and the plurality of tracks are reproduced with different positional relationships. A magnetic recording / reproducing apparatus, wherein a reproduction signal for each track is obtained based on a signal. The magnetic recording / reproducing apparatus according to claim 1,
The recording unit generates a signal having a recording wavelength equal to or greater than the minimum recording wavelength at a unique position for each track so that the reproducing unit can generate position information of the reproducing head for the plurality of tracks. A magnetic recording / reproducing apparatus that records as a separation pattern, and the reproduction unit obtains the channel estimation information by the signal processing based on a reproduction signal of the separation pattern. The magnetic recording / reproducing apparatus according to claim 1,
The recording unit records the plurality of tracks by a plurality of the recording heads,
The reproducing unit generates a plurality of reproduction signals for the plurality of tracks by the plurality of reproducing heads. The magnetic recording / reproducing apparatus according to claim 1,
A magnetic recording / reproducing apparatus, wherein the plurality of tracks have the same azimuth direction. A recording unit for recording a plurality of tracks, which is a unit of signal processing for data detection, on a magnetic recording medium by a recording head;
A recording apparatus comprising: a signal erasing unit that creates, as a guard band, a non-signal area for separating the plurality of tracks by the erasing head on the magnetic recording medium. The recording apparatus according to claim 11,
The signal erasure unit creates two guard bands for each unit of the signal processing. The recording apparatus according to claim 11,
The erasing head is a recording head for magnetic recording;
The recording apparatus, wherein the signal erasing unit includes an erasing signal generating unit that supplies an erasing signal to the erasing head. The recording device according to claim 13,
The erasing signal generator generates a repetitive signal having a recording wavelength equal to or shorter than the shortest recording wavelength as the erasing signal. The recording device according to claim 13,
The erasing signal generator generates a direct current signal as the erasing signal. The recording apparatus according to claim 11,
A recording apparatus, wherein the erasing head is made of a permanent magnet. A recording step of recording a plurality of tracks, which is a unit of signal processing for data detection, on a magnetic recording medium by a recording head;
And a signal erasing step of creating, as a guard band, a non-signal area for separating the plurality of tracks by the erasing head on the magnetic recording medium.   A plurality of tracks recorded by a recording head and being a unit of signal processing for data detection, and a no-signal area created by an erasing head and separating the plurality of tracks. Magnetic recording media.

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