JP3458640B2 - Digital signal recording / reproducing apparatus and recording method - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a digital signal recording / reproducing apparatus and a recording method , and more particularly to a digital signal recording / reproducing apparatus for recording an information signal in the form of a digital signal on a recording medium in a data block unit and reproducing the information signal. as well as
Regarding recording method .

[0002]

2. Description of the Related Art Conventionally, an information signal in the form of a digital signal is recorded by sequentially forming tracks on a magnetic tape by a rotary head, and the recorded digital signal is reproduced from an already recorded track using the rotary head. Digital V
TR is known. In this digital VTR, during normal reproduction, a rotary head that rotates at the same rotational speed as during recording is used to reproduce an already recorded digital signal from an already recorded track on a magnetic tape running at the same traveling speed as during recording. Then, after amplifying the reproduced signal with a preamplifier, A /
The reproduced digital signal whose waveform has been shaped by A / D conversion by the D converter is taken out, the waveform is equalized by the waveform equalizer, and the data is identified by using the clock signal extracted by the phase locked loop (PLL) circuit. .

In this case, the number of head rotations and the tape running speed during the recording and the normal reproduction are conventionally set to have certain fixed values. This is because if the head rotation speed and tape running speed during recording and during playback differ, the frequency band of the playback signal (playback signal data rate) differs from that during recording, and the above waveform equalization is performed according to the playback signal frequency band. This is because the frequency characteristics of the device, the oscillation frequency of the oscillator in the PLL, the sampling clock of the A / D converter, and the like must be changed, and cannot be followed as they are. Therefore,
Conventionally, information indicating the number of head revolutions or tape running speed during recording is not recorded on a magnetic tape, but is recorded at a predetermined specific value, and even during normal reproduction, the number of head revolutions and the tape having the specific value are recorded. I try to play at the running speed. this is,
The same applies not only to the digital VTR but also to a digital signal recording / reproducing apparatus for recording and reproducing a digital signal on an optical disk or a magnetic disk.

[0004]

However, if the number of head rotations and the tape running speed at the time of recording can be varied by one device, the application of recording and reproduction is widened and desirable. For example, when high quality image quality is strictly required, or when an image signal is recorded and reproduced with high image quality, the amount of data (data rate) per unit time is increased to record and reproduce, and When recording / reproducing for a long time is required, the demand can be met by reducing the data amount (data rate) per unit time and recording / reproducing.

Therefore, conventionally, in the case of a VTR, there is known an apparatus capable of selectively performing recording / reproducing in a standard time mode and recording / reproducing in a long time mode capable of recording / reproducing for a long time, for example, three times the standard time. There is. In this device, whether it was recorded in the standard time mode or the long time mode,
At the time of reproduction, it is determined by the cycle of the control pulse recorded on the control track along the longitudinal direction of the magnetic tape. However, when performing recording / reproducing that is not much different from the standard time mode, such as 1.25 times the standard time mode, the control pulse cycle is determined by the control pulse cycle determination method as in the conventional device described above. The difference is small, so it cannot be determined.

On the other hand, taking a digital VTR as an example, the rotational speed of the head is r (rpm), the running speed of the magnetic tape is v (mm / s), the recording rate is d (Mbps), and the number of rotary heads used. Where n is (r, v, d,
n) = (1800, 16.675, 14.1, 2) and so on. However, conventionally, the reproduction data rate of the reproduction processing circuit of one digital VTR is fixed, and the parameters (r, v, d, n) at the time of recording cannot be discriminated.
Using the same mechanism, (2r, 2v, 2d, n) and (1.
25r, 2.5v, 2.5d, 2n), etc., and various combinations of data rates cannot be recorded and reproduced.

As described above, conventionally, a dedicated system is used for recording / reproducing signals of different data rates due to the difficulty of reproducing signal processing in response to changes in the data rate and dealing with changes in the number of head revolutions and tape running speed. The current situation is that one device arbitrarily records the digital signal at an arbitrary data rate by arbitrarily selecting the number of head revolutions and the tape running speed, and reproduces the digital signal in the same manner as when recording. I couldn't do that.

The present invention has been made in view of the above points, and a digital signal recording / reproducing apparatus capable of recording a digital signal at an arbitrary data rate with one device and reproducing the digital signal in the same state as at the time of recording. And to provide a recording method .

[0009]

In order to achieve the above object, the present invention uses a rotary head provided on a rotary drum.
And diagonally wind it on the rotating drum over a specified angle range.
The digital signal is recorded on the tape-shaped recording medium
The information signal that has been
Racks are sequentially formed and recorded, and the same or different
Recorded on a tape-shaped recording medium using a rotary head
It reproduces the digital signal and outputs it through the reproduction signal processing circuit.
A digital signal recording / reproducing device for restoring a signal.
The rotational speed of the rotary head and the running speed of the tape-shaped recording medium.
Degree, recording data rate, and number of rotating heads used
The digital signal and the setting information.
/ (R · n) (where d is the recording data rate and r is the number of times
The number of rotations of the rotary head, n is the number of rotary heads used)
The same track on the tape recording medium so that it is almost constant
Recording means for recording at a substantially constant recording wavelength on a tape
When starting playback of the recording medium,
Running speed, recording data rate and usage
The number of rotary heads used is a condition expressed by d / (r · n)
Can reproduce a digital signal of almost constant recording wavelength
Playback device that sets and plays back one predetermined condition.
The setting information is detected from the reproduction signal of the loop-shaped recording medium, and by the control signal generated based on the detected setting information,
The number of rotations of the rotary head, the running speed of the tape-shaped recording medium, and
The number of rotary heads to be used is almost the same as that at the time of recording, and a control means for controlling the operation of the reproduction signal processing circuit is provided.

In order to achieve the above object,
Akira was recorded as a digital signal on a disc-shaped recording medium.
The information signal is sequentially tracked by multiple data blocks.
Next, form and record, and use the same or different head as when recording
A digital signal recorded on a disk-shaped recording medium.
Signal is reproduced and the information signal is restored through the reproduction signal processing circuit.
In a digital signal recording / reproducing device that
Relative speed, recording data rate and usage of disk-shaped recording medium
You can set the number of heads to be used and
Together with the digital signal, d / (r · n) (where d is the recorded data
Total rate, r is the relative speed between the head and the disk-shaped recording medium
, N is the number of rotary heads used) is almost constant
Almost constant on the same track of the disc-shaped recording medium
Recording means for recording at different recording wavelengths, and disk-shaped recording medium
When the playback of the
The speed, recording data rate and number of heads used are
Of the conditions expressed by (r · n), the
Set one predetermined condition that can reproduce the digital signal.
And a reproduction signal of a disc-shaped recording medium
Detect the setting information from the
Depending on the control signal generated, the head and disk recording medium
The relative speed of the body and the number of heads used are almost the same as when recording
And also controls the operation of the playback signal processing circuit.
It is configured to have steps.

According to the present invention, the number of rotations of the rotary head, the running speed of the tape-shaped recording medium, the recording data rate, and the number of rotary heads used can be arbitrarily set to record and reproduce digital signals. when the disc-shaped recording medium, the relative speed of the head and the disk-shaped recording medium, and arbitrarily set the number of heads for recording data rate and use it can be recorded and reproduced digital signal, also in one apparatus
More always reproduces digital signals under almost the same conditions as when recording
can do.

Here, the reproduction signal processing circuit has a waveform equalizer for equalizing the waveform of the reproduction signal based on the sampling clock, a detector for binarizing the reproduction signal output from the waveform equalizer, and this detection. A phase-locked loop circuit for regenerating a clock signal from the output signal of the detector, and a discriminator for discriminating the output signal of the detector by the output regenerated clock signal of the phase-locked loop circuit to obtain regenerated data, The control means detects the setting information from the output reproduction data of the discriminator, and controls the rotation of the rotary drum to which the rotary head is attached based on the detected value of the rotational speed of the rotary head, and the tape. Second control signal for controlling the number of revolutions of the capstan motor that drives the tape-shaped recording medium based on the detected value of the traveling speed of the recording medium, and the detected value of the recording data rate The frequency of the sampling clock supplied to the waveform equalizer is determined based on the third control signal for controlling the center frequency of the voltage controlled oscillator in the phase locked loop circuit, and the detected value of the number of rotary heads used. And a fourth control signal for controlling a switch circuit for selecting the reproduction signal of the rotary head, based on the above.

Further, according to the present invention, the above setting information is recorded in a subcode area in which a subcode as auxiliary information is recorded, which is different from a main data recording area as main information of a digital signal. Since the information in the subcode area can be reproduced even in a relatively poor reproduction state, the setting information can be reproduced even if the speed of the head or the recording medium is unknown.

Furthermore, in order to achieve the above-mentioned object, the recording method of the present invention uses a rotary drum provided with a rotary head.
A te that travels while being diagonally wound over a specified angle range.
On the loop-shaped recording medium by a rotary head or by a rotating disk.
With a digital signal by a head on the disk-shaped recording medium
The tracked information signal is a track consisting of multiple data blocks.
For recording on a recording medium that sequentially forms and records
The rotation speed of the rotary head or the rotation of the disk-shaped recording medium.
Number of turns, running speed of tape-shaped recording medium, recording data
And the number of rotating heads used or the number of heads is arbitrary
, And the setting information together with the digital signal is d /
(R · n) (where d is the recording data rate and r is the rotation
Rotational speed of head or phase of head and disk-shaped recording medium
Vs. speed, n is the number of rotating heads or the number of heads used)
So that the
The recording is performed at a substantially constant recording wavelength.

[0015]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is a block diagram showing an embodiment of a reproducing system of a digital signal recording / reproducing apparatus according to the present invention. In this embodiment, the first rotary head 1 having a first azimuth angle, which is provided to face a rotary drum, which is a rotary body, by 180 degrees.
a and a second rotary head 1b having a second azimuth angle,
A third rotary head 1c having a second azimuth angle, which is provided on the rotary drum in the vicinity of the first rotary head 1a and constitutes a pair head, and a third rotary head 1c facing the third rotary head 1c by 180 degrees Of the fourth rotary heads 1d having the first azimuth angle and forming the paired head with the second rotary head 1b, the first and second rotary heads 1a and 1b are used, or the first to the fourth rotary heads are used. Rotary heads 1a-1
A helical scan method in which a digital information signal is recorded / reproduced in data block units on a magnetic tape 2 which is obliquely wound around an outer peripheral side surface of a rotary drum over an angular range of about 180 degrees and runs at a constant speed by using d. VTR
Applied to.

The above digital information signal is composed of, for example, main data, which is main information, and auxiliary data called a pack (data). Here, the pack includes a cassette ID, a time code, a recording date and time, source information (for example, a channel and a program index number when a digital broadcast signal is recorded), text data (for example, a title for each program, an outline, etc.). It is fixed-length data containing auxiliary information and its identification information.

The above pack is recorded on the magnetic tape 2 along with main data and subcode data on each inclined track. Each tilted track is configured by arranging a plurality of fixed amount data areas called sync blocks corresponding to the data blocks in accordance with the scanning of the rotary heads 1a to 1d. FIG. 2 shows an example of the format of this sync block. As shown in the figure, the sync block stores a 2-byte synchronization signal (Sync) area 21 for reproducing the sync block, a 3-byte address information (ID) area 22, and various information 3 A byte header storage area 23, a 96-byte substantial data storage area 24, and an 8-byte parity area 25 for error correction of information of this sync block are time-sequentially combined 112 in total. It is composed of bytes.

FIG. 3 shows a track format of an example of a slanted track on the magnetic tape 2 reproduced according to the embodiment of the present invention. As shown in the figure, one track includes a margin area 31, a preamble area 32, a subcode area 33, a postamble area 34, an IBG area 35, a preamble area 36, a main data area 37,
The error correction code area 38, the postamble area 39, and the margin area 40 are formed, and are composed of 356 sync blocks in total.

Of the main data area 37 and the error correction code area 38, the main data area 37 is set to 306 sync blocks which is a multiple of 6 sync blocks, for example.
The error correction code area 38 is an area in which an outer code (C2 code) for error correction is recorded and is composed of 30 sync blocks. The sub-code area 33 is composed of 4 sync blocks (= 448 bytes), and each sync block is composed of four sub-code sync blocks 41 of 28 bytes (= 28 symbols).

As shown in FIG. 4, one sub-code sync block 41 has a two-symbol sync signal (Sync) area 43 and one-symbol address information (ID0, I0).
D1) areas 44 and 45 and address information ID0 and ID
An area 46 of 1 symbol of ID parity (IDP) for identifying an error of 1, an area 47 of 1 symbol of format ID, an area 48 of subcode data of 18 symbols, and error detection of this subcode sync block And a parity area 49 of 4 symbols. One symbol is one byte. The subcode data recorded in the area 48 is auxiliary information such as a title of recorded contents, recording date and time, time, and absolute address on the tape. In the embodiment of the present invention, information indicating the combination of (r, v, d, n) is recorded in the subcode sync block 41.

More specifically, in the area 47 of one symbol of the format ID in the subcode sync block 41, the block size of the error correction code (ECC) recorded in the area 38 of FIG. E per truck
The CC block number, the program number, and the rotation number of the rotary drum are recorded, and the area 4 of one symbol of the format ID in another subcode sync block 41 on the same track is recorded.
A recording mode and the like are recorded in 7.

Normally, the information on the number of revolutions of the rotary drum is recorded in 2 bits and the information in the recording mode is recorded in 4 bits. Here, by using these 6 bits in total, the above (r, v, d , N) is recorded. For example, "000000" is (r, v, d,
n) = (1800, 16.675, 14.1, 2), which means "010
000 "is (r, v, d, n) = (2250, 33.35, 35.2
Arrange in advance such as to mean 5, 4).

As another method, when the rotation speed of the 2-bit rotary drum is "11", the sub-code data area 48
(R, v, d, n) may be individually defined. As is clear from these, (r, v,
It is not necessary to record all the respective elements of d, n) as information. For example, a mechanism may be used in which only the rotation speed r of the rotating drum (rotating head) is recorded and the other elements v, d, and n are uniquely determined from r.

Besides, only (r, n) is recorded, and (v,
It is also possible to correspond to d). Information can be selected and recorded in an efficient manner, for example, by using all the previous 6 bits, 2 ⁶ modes can be set, and by using 3 bits out of 6 bits, 8 modes can be set. The point is that the combination of elements can be determined.

Further, in this embodiment, (r,
The wavelength of the digital signal recorded on the magnetic tape 2 is always recorded at a substantially constant value regardless of the value of the information indicating the combination of v, d, n). That is, here, recording is performed so as to satisfy the condition of the following equation.

[0027]

[Equation 1] As described above, in this embodiment, the rotational speed r of the rotary drum (rotary head), the tape traveling speed v, the recording rate d, and the number of rotary heads used n are arbitrarily set, and digital signals are shown in FIGS. In the format shown, and (1)
As shown in the formula, while recording at a predetermined wavelength, in the sub-code area 33 of the same track as the main data,
Information indicating the combination of (r, v, d, n) is recorded.

Next, the magnetic tape recorded as described above.
The operation of the reproducing system will be described with reference to FIG. Recorded
When playing the magnetic tape 2 for the first time,
(Rotation head) rpm r, tape running speed v, recording level
The information on the port d and the number of rotary heads used n is unknown.
And one combination that satisfies the formula (1)       (R, v, d, n) = (r₁, V₁, D₁, N ₁) (2) Play with. That is, at the start of tape reproduction,
The drum servo circuit 16 rotates the rotating drum.
Initial setting speed r₁Rotating with rotating head 1a ~
The rotation speed of 1d is r₁And the capstan servo circuit 17
Started the capstan motor that runs the magnetic tape 2.
Rotate the tape at the set speed and set the tape running speed to v₁And then
Initially installed the dead switching (HSW) pulse generation circuit 5.
Generates a fixed HSW pulse and supplies it to the switch circuit 4.
The number of rotating heads used is n₁And

As a result, the rotary heads 1a to 1d sequentially start scanning the recording tracks on the recorded magnetic tape 2. At this time, in some cases, even if the recording trace of the recording track and the scanning loci of the rotary heads 1a to 1d do not match and it is impossible to scan the entire recording track, the subcode sync block 41 is normally used. Is always recorded on one track, and it is designed so that data can be extracted even in a relatively bad reproduction state so that high-speed tape feed reproduction can be sufficiently performed. Therefore, the subcode area 3 which is a part of the track
The third recorded subcode sync block 41 can be reproduced relatively easily.

The reproduced signals of the rotary heads 1a, 1b, 1c and 1d are respectively pre-amplified by the preamplifiers 3a, 3b, 3c and 3d via a rotary transformer (not shown) and then supplied to the switch circuit 4. At HS
By the HSW pulse from the W pulse generation circuit 5, only n ₁ (n ₁ is 4 or less in this example) rotary head reproduction signals are selected, combined in time series and taken out, and A /
It is supplied to the D converter 6. The A / D converter 6 performs A / D conversion on the input reproduction signal based on the sampling clock output from the sampling clock generation circuit 8, and supplies the waveform-shaped reproduction digital signal to the waveform equalizer 7.

The waveform equalizer 7 equalizes the waveform of the input reproduced digital signal by a known method based on the sampling clock output from the sampling clock generation circuit 8. Here, the sampling clock output from the sampling clock generation circuit 8 to the A / D converter 6 and the waveform equalizer 7 is a clock having a frequency that satisfies the expression (2) and is at least twice the upper limit frequency of the recording signal. , In the initial state, the digital signal of the recording rate d ₁ is A / D converted,
In addition, the clock has a frequency that can equalize the waveform.

The reproduced digital signal output from the waveform equalizer 7 is compared in magnitude with a predetermined threshold value in the detector 9 to be converted into a binary signal, and then the discriminator 10 and the PLL.
Each is supplied to the circuit 11. The center oscillation frequency of the internal voltage controlled oscillator (VCO) of the PLL circuit 11 is controlled by the speed information voltage from the speed information voltage generation circuit 12, and in the initial state, the recording rate d ₁
The center oscillation frequency is controlled so that the clock signal in the digital signal can be extracted from the digital signal. The reproduced clock signal output from the PLL circuit 11 is supplied to the discriminator 10, where the reproduced signal from the detector 9 is latched to identify the data.

Identification data output from the discriminator 10 and P
The reproduction clock signal output from the LL circuit 11 is supplied to the synchronization signal detection circuit 13 to detect a synchronization signal having a known fixed pattern, and the error correction circuit 14 performs error correction using the error detection code in the reproduction data. Is restored to correct data, and the subsequent processing circuit (not shown) as valid data
While being output to, it is input to the mode detection decoder 15.

The mode detection decoder 15 detects the data value of the subcode sync block from the input data.
Therefore, when the subcode area 33 is reproduced shortly after the reproduction of the recorded magnetic tape 2 is started, information indicating the combination of (r, v, d, n) recorded by the mode detection decoder 15 is detected. To be done.

The mode detection decoder 15 generates a first control signal based on the detected drum (head) rotation speed r on the basis of this detection information and supplies it to the drum servo circuit 16 so that the drum motor inside the drum servo circuit 16 is supplied. Is the detected rotation speed r
Drive control is performed so as to be equal to
A second control signal based on the above is generated and supplied to the capstan servo circuit 17, and the rotational speed of the capstan motor inside the capstan servo circuit 17 is sandwiched between the capstan and the pulley (both not shown) to run. The traveling speed of the magnetic tape 2 is controlled to be equal to the detected tape traveling speed v.

Further, the mode detection decoder 15 has a detection register.
Recording rate d Generate a third control signal based on
Ring clock generation circuit 8 and speed information voltage generation circuit 1
Sampling clocks that are respectively supplied to and output to
Clock frequency and speed information voltage
Controlled to a value suitable for digital signal reproduction, and detection rotation
Generate a fourth control signal based on the number of heads used n
Supply to the HSW pulse generation circuit 5 to generate HSW pulse
Detection times are controlled by controlling the number and phase of the output HSW pulse of the circuit 5.
You can select the playback signals of the rotating heads with n rotating heads.
To do so.

The above-mentioned drum servo circuit 16 and capstan servo circuit 17 each have a known structure, and a feedback loop circuit for driving and controlling the drum motor and the capstan motor at a constant rotation speed and at a constant phase. In order to control the rotation speed of the drum motor or the capstan motor as described above, for example, the frequency of the FG pulse having the repeating frequency corresponding to the rotation speed of the motor is compared with the frequency of the reference signal, and the frequency difference is determined according to the frequency difference. The reference signal of the frequency detection circuit that outputs the speed error signal may be variably controlled by the first and second control signals.

FIG. 5 is a block diagram showing an example of the sampling clock generation circuit 8. As shown in the figure, the sampling clock generation circuit 8 has a clock oscillator 51 that oscillates and outputs a clock pulse having a constant repetition frequency, and a clock pulse from the clock oscillator 51 is 1/1.
Frequency divider 52 for dividing by 0, frequency divider 53 for dividing by 1/8, 1
/ 5 frequency divider 54, ¼ frequency divider 55,
It comprises a selector 56 which selects one of the output signals of the frequency dividers 52 to 55 by an external input control signal (the third control signal) and outputs it as a sampling clock.

Here, assuming that the repetition frequency of the output clock pulse of the clock oscillator 51 is, for example, 270 MHz, the output pulse frequency of the frequency divider 52 is 27 MHz, the output pulse frequency of the frequency divider 53 is 33.75 MHz, and the frequency divider 54. Has an output pulse frequency of 54 MHz, and the frequency divider 55 has an output pulse frequency of 67.5 MHz. r = 1800
When 27 MHz is the sampling clock at rpm, r is 2250 rpm, 3600 rpm, and 450 in order due to the output pulses of the frequency dividers 53, 54, and 55.
A signal having a data rate ratio at 0 rpm can be processed by the output sampling clock of the selector 56.

As described above, according to this embodiment, digital signals of various data rates can be reproduced in the same state as when recording. Therefore, one recording / reproducing apparatus can perform recording / reproducing for various purposes depending on which of the image quality and the recording / reproducing time is prioritized.

Next, a second embodiment of the present invention will be described. In this embodiment, a single digital VTR having three modes is assumed, and the block configuration itself is the same as in FIG. 1, but the information of (r, v, d, n) is shown in the table below. The feature is that it is set as 1.

[0042]

[Table 1] In addition, in Table 1, d is shown as a channel rate. For example, in mode 3, 300 tracks per second (= 45
00 ÷ 60 × 4) is formed, and one track is shown in FIG.
356 sync blocks (ie, 3
Since 56 × 112 × 8 bits are recorded, the recording rate d is 95.69280 (= 356 × 112 × 8 × 30).
0 ÷ 10 ⁶ ) Mbps.

If the sampling clock in mode 1 is set to 27 MHz, which is higher than the data rate of 19.13856 Mbps at that time, the number of rotary heads used in mode 2 is twice as large as that in mode 1, so that one channel is used. Since the data rate of 23.9232 (= 47.84640 / 2) Mbps is 1.25 times that of mode 1, 33.75 MHz, which is 1.25 times 27 MHz, is used as the sampling clock. In addition, since the number of rotary heads used in mode 3 is twice that in mode 1, the data rate per channel is 47.8464.
67.5MHz (5 which is higher than (= 95.69280 / 2) Mbps
4 MHz may be used) as the sampling clock.

In this embodiment, the digital signal is recorded so that d / (rn) is approximately 5316. 3 in any of modes 1 to 3 so that the equation (1) is satisfied, and r Since the relationship between v and v is fixedly determined, the two-bit rotary drum arranged in the area 47 of one symbol of the format ID in the subcode sync block 41 described in the first embodiment. Using the information on the rotation speed, (mode 1, mode 2, mode 3) =
It is recorded as (00, 01, 10). These are equivalent to recording the number of rotations of the rotating drum on the magnetic tape.

At the time of reproduction, first, reproduction of the digital signal recorded on the recorded magnetic tape in the state of mode 1 is started, and the information on the rotation speed of the 2-bit rotary drum reproduced from the sub-code area is, for example, If "10" is detected, the mode 3 shown in Table 1 at that time is shown.
, Drum rotation speed r to 4500 rpm, tape running speed v to 83.36 mm / s, rotation head number n to be used during playback to 4, and sampling clock 67.5 MH
The circuit is switched so as to operate in each z.

As a result, as described with reference to FIG.
The recording signal can be reproduced under the same conditions as when recording. Therefore, the second embodiment also has the same features as the first embodiment.

Next, a third embodiment of the present invention will be described. This embodiment is characterized in that the circuit unit including the A / D converter 6, the waveform equalizer 7, and the sampling clock generation circuit 8 shown in FIG. 1 has the block configuration shown in FIG. Have. That is, in FIG. 6, the reproduction signal output from the switch circuit 4 shown in FIG. 1 is directly supplied to the electronic filter type analog waveform equalizer 61, and at the same time, from the mode detection decoder 15 shown in FIG. A control signal is input, and a selector 62 that selects one of preset n different voltages V1 to Vn and supplies it to the electronic filter type analog waveform equalizer 61 as a control voltage is formed. .

In this embodiment, the control signal generated according to the information of the recording rate d detected by the mode detection decoder 15 shown in FIG. 1 is applied to the selector 62,
Of V1 to Vn, the most suitable voltage for the detected recording rate d is selected. As a result, the electronic filter type waveform equalizer 61 equalizes the waveform of the reproduced signal from the switch circuit 4 with the equalization characteristic according to the voltage selected by the selector 62. That is, the electronic filter type waveform equalizer 61 performs waveform equalization most suitable for the data rate of the reproduction signal.

In the above embodiments, the digital VTR is described as an example, but the present invention is not limited to this, and a digital signal is recorded / reproduced on / from a disc-shaped recording medium such as an optical disc or a magnetic disc. The present invention can also be applied to a recording / reproducing device that operates. in this case,
The rotational speed r of the rotary drum (rotary head) and the tape running speed v are represented by the relative speed between the head and the recording medium, and a plurality of modes in which the relative speeds are different from each other are set, and in which mode recording / reproduction is performed. Even in this case, the digital signal is recorded so that the recording wavelength becomes constant.

The sampling clock supplied to the A / D converter 6 and the waveform equalizer 7 is generated separately from the clock obtained by the PLL 11, but P
The data extraction bit clock obtained by the LL 11 can also be used as the sampling clock of the A / D converter 6 and the waveform equalizer 7. In this case, the sampling clock generating circuit 8 is not necessary, so that the circuit configuration can be made more inexpensive and simple.

[0051]

As described above, according to the present invention,
The speed of the head and recording medium, the recording data rate, and the number of heads to be used are set arbitrarily to record the digital signal on the recording medium at a substantially constant recording wavelength, and at the time of reproduction, the setting is that the signal is reproduced from the same track as the digital signal. Information is detected, and a control signal is generated based on the detected setting information. The speed of the head and the recording medium and the number of heads used are made almost the same as those at the time of recording by the control signal, and the operation of the reproduction signal processing circuit. The digital signal can be always reproduced by one device under almost the same conditions as when recording, so that the speeds of the head and recording medium, the number of heads used, and the recording data rate are different. A single recording / reproducing device can record / reproduce various modes and does not require a dedicated device for each. Can.

Further, according to the present invention, when recording a digital signal on a tape-shaped recording medium or a disk-shaped recording medium, the selection of which of the quality of the digital signal to be recorded / reproduced and the recording / reproduction time is prioritized is performed. Since the speeds of the heads and the recording medium, the number of heads used, and the recording data rate can be arbitrarily set, the recording can be performed more finely than in the past, and thus recording and reproduction corresponding to various uses can be performed as compared with the conventional.

[Brief description of drawings]

FIG. 1 is a configuration diagram of an embodiment of a reproducing system of a digital signal recording / reproducing apparatus according to the present invention.

FIG. 2 is a diagram showing an example of a sync block format of a digital signal recorded / reproduced in an embodiment of the present invention.

FIG. 3 is a diagram showing an example of a format of a track recorded / reproduced in the embodiment of the present invention.

FIG. 4 is a diagram showing an example of a format of a subcode sync block in a subcode area in FIG.

5 is a block diagram of an example of a sampling clock generation circuit in FIG.

FIG. 6 is a block diagram of another embodiment of the main part of the digital signal recording / reproducing apparatus according to the present invention.

[Explanation of symbols]

1a-1d rotating head 2 magnetic tape 4 switch circuit 5 Head switching (HSW) pulse generation circuit 6 A / D converter 7 Waveform equalizer 8 Sampling clock generator 10 discriminator 11 Phase locked loop (PLL) circuit 12 Speed information voltage generator 15 mode detection decoder 16 drum servo circuit 17 Capstan servo circuit 33 subcode area 41 Subcode sync block 51 clock oscillator 52-55 frequency divider 56,62 selector 61 Electronic filter type analog waveform equalizer

─────────────────────────────────────────────────── --- Continuation of the front page (56) References JP-A-7-115617 (JP, A) JP-A-6-60302 (JP, A) JP-A-5-227507 (JP, A) JP-A-8- 279129 (JP, A) JP-A-2-202789 (JP, A) (58) Fields investigated (Int.Cl. ⁷ , DB name) G11B 20/10 G11B 5/09

Claims (5)

(57) [Claims] 1. A plurality of information signals, which are digital signals, are recorded on a tape-shaped recording medium that runs while being obliquely wound on a rotary drum over a predetermined angle range by using a rotary head provided on the rotary drum. Tracks consisting of data blocks are sequentially formed and recorded, and the digital signal recorded on the tape-shaped recording medium is reproduced by using the same or different rotary head as at the time of recording, and the information is passed through a reproduction signal processing circuit. In a digital signal recording / reproducing apparatus for restoring a signal, the rotational speed of the rotary head, the traveling speed of the tape-shaped recording medium, the recording data rate, and the number of rotary heads to be used are arbitrarily set, and the setting information is set to the digital signal. Together with
D / (r · n) (where d is the recording data rate
Where r is the number of revolutions of the rotary head, and n is the number of revolutions to be used.
A recording unit that records at a substantially constant recording wavelength on the same track of the tape-shaped recording medium so that the number of transfer heads is substantially constant; The running speed of the tape-shaped recording medium, the recording data rate, and the number of rotary heads to be used are calculated as d / (r
-Reproducing means for reproducing the digital signal having a substantially constant recording wavelength among the conditions represented by (n) by setting the reproducing means to reproduce the setting signal from the reproduction signal of the tape-shaped recording medium. The control signal generated based on the detected setting information causes the number of rotations of the rotary head, the traveling speed of the tape-shaped recording medium, and the number of rotary heads to be used to be substantially the same as during recording, and the reproduction. And a control means for controlling the operation of the signal processing circuit. 2. The setting information is the digital signal.
Auxiliary information that is different from the main data recording area that is the main information
Information is recorded in the subcode area where the subcode is recorded.
The reproduced signal processing circuit includes a waveform equalizer that equalizes the reproduced signal based on a sampling clock, and a detector that binarizes the reproduced signal output from the waveform equalizer. A phase-locked loop circuit that regenerates a clock signal from the output signal of the detector, and a discriminator that discriminates the output signal of the detector by the output regenerated clock signal of the phase-locked loop circuit to obtain regenerated data. The control means detects the setting information from the output reproduction data of the discriminator, and controls the rotation of the rotary drum to which the rotary head is attached based on the detected value of the rotational speed of the rotary head. A second control signal for controlling the number of revolutions of a capstan motor that runs the tape-shaped recording medium based on a control signal and a detected value of the running speed of the tape-shaped recording medium. And the frequency of the sampling clock supplied to the waveform equalizer based on the detected signal of the recording data rate and the center frequency of the voltage controlled oscillator in the phase locked loop circuit. A control signal and a fourth control signal for controlling a switch circuit for selecting a reproduction signal of the rotary head based on a detected value of the number of rotary heads to be used are respectively generated and output. The digital signal recording / reproducing apparatus according to claim 1 . 3. A disc-shaped recording medium is recorded with an information signal, which is a digital signal, by sequentially forming tracks consisting of a plurality of data blocks, and using the same or different head as at the time of recording. In a digital signal recording / reproducing apparatus for reproducing the digital signal recorded on a recording medium and restoring the information signal through a reproduction signal processing circuit, a relative speed between the head and the disk-shaped recording medium, a recording data rate, and a head to be used. the number was arbitrarily set, both the setting information said digital signal, d / (r · n)
(However, d is the recording data rate, r is the head
And the relative speed of the disk-shaped recording medium, n is the number of times
In order to keep the number of
Recording at the same recording wavelength on the same track of the recording medium.
Recording means for recording, and at the start of reproduction of the disc-shaped recording medium, the relative speed between the head and the disc-shaped recording medium, the recording data rate, and the number of heads used are represented by d / (r · n).
Among the conditions, a reproducing means for setting and reproducing to one predetermined condition capable of reproducing the digital signal of the substantially constant recording wavelength, and the setting information is detected from the reproduction signal of the disc-shaped recording medium, and the detected information is detected. The control signal generated based on the setting information makes the relative speed between the head and the disk-shaped recording medium and the number of heads to be used substantially the same as at the time of recording, and has a control means for controlling the operation of the reproduction signal processing circuit. A digital signal recording / reproducing apparatus characterized by the above. 4. The setting information is of the digital signal.
Auxiliary information that is different from the main data recording area that is the main information
Information is recorded in the subcode area where the subcode is recorded.
The digitizer according to claim 3, which is recorded.
Signal recording / reproducing device. 5. A rotary drum provided with a rotary head.
A tape that travels while being wound diagonally over a constant angle range
On the recording medium, or by the rotating head
Digital signal from the head on the disk-shaped recording medium
The information signal is
Recording method for recording media that sequentially forms and records
The rotational speed of the rotary head or the disk-shaped recording medium.
Rotation speed, running speed of the tape-shaped recording medium, recording data
Rate and the number of rotary heads used or the head
Set the number of cards to any
Along with the signal, d / (r · n) (where d is the recorded data
Total rate, r is the rotational speed of the rotary head or the head
Relative speed between the disk and the disk-shaped recording medium, n is before use
The number of rotary heads or the number of heads is almost constant.
So that they are almost in the same track on the tape-shaped recording medium.
A recording method characterized by recording at a fixed recording wavelength .