JP2778217B2 - Data recording device - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a data recording apparatus, and more particularly, to a data recording apparatus which can record information data at a variable speed.

B. Summary of the Invention The present invention provides a data recording apparatus in which a high frequency component of information data is emphasized with an emphasis amount corresponding to a data rate, so that the same magnetization pattern can be recorded on a magnetic recording medium even when the data rate is different. Can be formed.

C. Related Art There is a data recording apparatus that can record information data at a high density by using a digital video tape recorder based on a helical scan method.

That is, the recording system of such a data recording device 1 can be represented by an equivalent circuit shown in FIG. 3, in which information data DT _REC having a predetermined data rate is amplified by the recording amplifier circuit 2, and the resulting recording is performed. The signal S _REC is supplied to the head 4 through the rotary transformer 3, whereby information data DT _REC is recorded on the magnetic tape 5.

Here, L _S of the rotary transformer 3 is a loss due to the rotary transformer, and L _H of the head 4 is an inductance of the rotary transformer 3 and the head 4 together.

Further, the capacitance _CH represents the output capacitance of the recording amplifier circuit 2 and the capacitance including the distribution capacitance of the circuit, the lead wire, the rotary transformer 3 and the like.

In addition, the influence of the resonance characteristic generated in the resonance circuit by the capacitance C _H and the inductance L _H of the head 4 is determined by the damping resistance R _H
Thus, the correction can be made as much as possible.

In this way, in the data recording device 1, usually 88
Information data DT _REC comprising at data rates up to a frequency f _max is recorded as a recording signal S _REC consisting of 44 [MHz] to [Mbps], the magnetization pattern at recording wavelength of 0.9 [μm] on the recording track of the magnetic tape 5 To form

For example, as shown in FIG. 4 (A), when the information data DT _REC in which the short wavelength pattern PTN _S appears following the long wavelength pattern PTN _L is digitally recorded on the magnetic tape 5, FIG. As shown in ()), the amplitude of the short wavelength pattern PTN _S decreases and waveform interference HX occurs.

Therefore, when digitally recording the information data DT _REC , the edge before the recording signal S _REC may be emphasized or the recording signal S _REC may be emphasized.
_The pulse width modulation is performed by shortening the long wavelength component of the _REC within a range not _exceeding T / 2.

If practical data recording apparatus 1 uses the front edge emphasizing circuit in advance differentiating circuit configuration, as shown in FIG. 4 (C), a recording amplifier emphasizes the front edge E _G information data DT _REC The signal is input to the circuit 2.

By the way, in such a data recording device 1, the rotation speed of the head 4 and the running speed of the magnetic tape 5 are controlled,
The relative speed of the magnetic tape 5 and the head 4 in the recording track direction is controlled to 1/1, 1/2, 1/4, 1/8, 1/16, 1/24 times, etc., so that the data rate is 88. , 44, 22, 11, 5.50, 3.67 (Mb
ps) information data, i.e. the highest frequencies 44, 22, 11, 5.
Recording signals of 50, 2.25, and 1.84 [MHz] can be recorded and reproduced.

That is, for example, the relative speed of the magnetic tape 5 and the head 4 in the recording track direction is set to 1 for the information data DT _REC recorded with the recording signal S _REC having the data rate of 88 [Mbps], that is, the maximum frequency f _max of 44 [MHz]. If the variable speed control is performed at a speed of / 2, the data rate becomes 44 [Mbps] (that is, the maximum frequency f
_The data can be read out as information data DT _REC of which _max1 is 22 [MHz], thereby enabling reproduction at 1/2 times the low speed.

Conversely, information data DT _REC recorded with a recording signal S _REC having a data rate of 22 [Mbps], that is, a maximum frequency f _max3 of 11 [MHz] is _compared with the relative speed of the magnetic tape 5 and the head 4 in the recording track direction. If the variable speed control is performed at 1/1 times, the data rate is 88 [Mbps] (that is, the maximum frequency f _max1 is 4
4 [MHz]) of information data DT _REC , thereby enabling a four-fold high-speed reproduction.

Actually, in the case of this data recording device 1, 1/1
By being able to record and reproduce at variable speeds between ~ 1 / 24x speed, recording observation data that slowly changes like astronomical observation at a data rate of 3.67 (Mbps), 88 (Mbp)
s] so that analysis can be performed in a short time.

On the other hand, observation data and measurement data that change quickly are recorded at a data rate of 88 [Mbps] and 3.67 [Mbp]
s] and can be analyzed at a low speed and reliably, so that the information data DT _REC can be used as a buffer for frequency conversion.

D Problems to be Solved by the Invention However, in the data recording apparatus 1 having such a configuration, the differential coefficient of the front edge emphasizing circuit disposed in the preceding stage of the normal recording system and the recording amplifier circuit 2 is the information having a data rate of 88 [Mbps]. the data DT _REC as a recording signal S _REC the highest frequency f _max is 44 [MHz], is set so as to record, for example, the data rate for this is at 1/2 and 1/4 44
When the information data DT _REC of [Mbps] or 22 [Mbps] is recorded, there is a problem that a front edge of the information data DT _REC is excessively emphasized.

In practice, if the degree of emphasis on the front edge of the information data DT _REC differs depending on the data rate as described above, even if a magnetization pattern is formed on the recording track at a recording wavelength of 0.9 (μm) as short as possible, an equalizer for reproduction is used. There is a problem that a difference occurs due to characteristics and the like, and eventually, compatibility of information data between different data rates cannot be maintained.

The present invention has been made in consideration of the above points, and has as its object to propose a data recording apparatus that can form the same magnetization pattern on a magnetic recording medium even when the data rates are different.

E. Means for Solving the Problem In order to solve the problem, in the present invention, the information data DT _REC having an arbitrary data rate is transferred to the magnetic recording medium 5.
In the data recording device 10 to be recorded above, high-frequency emphasis means 11, 12, and 13 for emphasizing the high-frequency component of the information data DT _REC with an emphasis amount corresponding to the data rate are provided.

F function By emphasizing the high frequency components of the information data DT _REC with an emphasis amount corresponding to the data rate, the same magnetization pattern can be formed on the magnetic recording medium 5 even when the data rate is different.

G Example Hereinafter, an example of the present invention will be described in detail with reference to the drawings.

In FIG. 1, in which parts corresponding to those in FIG. 3 are assigned the same reference numerals, reference numeral 10 denotes a data recording device as a whole, and information data DT _REC is input to an input terminal of a switching circuit 11.

This switching circuit 11 has first, second and third output terminals a and b.
And c, the first to third output terminals a to c are switched and controlled by a rate signal _SRT corresponding to the data rate of the information data DT _REC , and the third output terminal c is selected. The information data DT _REC is directly input to the recording amplification circuit 2 as the second information data DT _REC1 .

Alternatively, when the first or second output terminal a or b is selected, the first or second front edge enhancement circuit 12 or
The front edge of the information data DT _REC is emphasized by a predetermined emphasis amount through 13 and input to the recording amplification circuit 2 as the second information data DT _REC1 .

The first pre-edge emphasizing circuit 12 is a differential circuit configuration as a whole, as well as connected in series with a resistor R ₁₀ and capacitor C ₁ connected in parallel a first output terminal a and between the recording amplifier circuit 2, one end which are connected to the other end of the grounding resistor R ₁₁ between the resistor R ₁₀ and the recording amplifier circuit 2.

The resistance R ₁₀ , the resistance R ₁₁ and the capacitor C ₁ are, for example, in a degree corresponding to recording information data DT _REC having a data rate of 88 [Mbps] (that is, the maximum frequency f _max is 44 [MHz]). The value is selected to be a derivative that can emphasize the previous edge.

Similarly, made of a differentiating circuit configuration as a whole a second front edge emphasizing circuit 13, while a resistor R ₂₀ and capacitor C ₂ connected in parallel to the series with the first output terminal b and between the recording amplifier circuit 2 one end is constituted by connecting the other end of the resistor R ₂₁ which is grounded between the resistance R ₂₀ and the recording amplifier circuit 2.

The resistor R _20, resistor R ₂₁ and capacitor C _2, for example information data DT _REC (i.e. maximum frequency f _max is 22 [MHz]) of the data rate is 44 [Mbps] at a degree corresponding to the time of recording The value is selected to be a derivative that can emphasize the previous edge.

According to the experiment, the information data DT _REC was
Waveform interference HX (4th
FIG. 4 relates to the magnetic permeability μ of the head 4 and the magnetic tape 5 as a recording medium. It was found that if the recording medium is the same, the higher the magnetic permeability μ of the head 4, the less the waveform interference occurs.

The magnetic permeability μ of the head 4 is 88, 44, 22, 11 [Mb
ps] according to the data rates RT ₈₈ , RT ₄₄ , RT ₂₂ , and RT ₁₁ as shown in FIG.

Therefore, when the same magnetic tape 5 and head 4 are used, the lower the frequency of the recording signal S _REC supplied to the head 4, the less waveform interference occurs, and thus the amount of emphasis on the front edge may be small.

Based on such a principle, the data recording device of this embodiment
In FIG. 10, first and second front edge emphasizing circuits 12 and 13 having emphasis amounts corresponding to data rates of 88 and 44 [Mbps] are provided as emphasis amounts of the front edge of the information data DT _REC. DT _REC data rate is 88 [Mbps] or 4
In the case of 4 [Mbps], the first or second front edge emphasizing circuit 12
Alternatively, the previous edge is emphasized through 13 and input to the recording amplification circuit 2.

When the data rate of the information data DT _REC is 22 [Mbps] or less, the information data DT _REC is directly input to the recording amplifier circuit 2 without emphasizing the previous edge.

In the above configuration, for example, a data rate of 88 [Mbp
When recording information data DT _REC of s], rate signal S _RT
Selects the first output terminal a of the switching circuit 11.

With this configuration, the first edge of the information data DT _REC is emphasized by the first front edge emphasis circuit, and the second information data DT _REC is emphasized.
_The recording signal S _REC amplified as the _{REC 1} by the recording amplifier circuit 2 and having a maximum frequency f _max of 44 [MHz] is supplied to the head 4 through the rotary transformer 3.

At this time, the relative speed of the magnetic tape 5 and the head 4 in the recording track direction is selected to be 1/1 times, whereby a magnetization pattern having the shortest recording wavelength of 0.9 [μm] is formed on the recording track of the magnetic tape 5.

Further alternatively, if the data rate for recording information data DT _REC of 44 [Mbps], selects the second output terminal b of the rate signal S _RT Niyotsu Te switching circuit 11.

In this way, the second edge of the information data DT _REC is emphasized by the second front edge emphasizing circuit 13 and the second information data D
A recording signal S _REC amplified as T _{REC1 by the} recording amplifier circuit 2 and having a maximum frequency f _max1 of 22 [MHz] is supplied to the head 4 through the rotary transformer 3.

At this time, the relative speed of the magnetic tape 5 and the head 4 in the recording track direction is selected to be 1/2 times, whereby a magnetization pattern having the shortest recording wavelength of 0.9 [μm] is formed on the recording track of the magnetic tape 5.

Further alternatively, if the data rate for recording information data DT _REC of 22 [Mbps], to select the third output terminal c of the rate signal S _RT Niyotsu Te switching circuit 11.

In this way, the information data DT _REC can be
Information data DT _REC1 is amplified by the recording amplifier circuit 2,
A recording signal S _REC whose maximum frequency f _max2 obtained as a result is 11 [MHz] is supplied to the head 4 through the rotary transformer 3.

At this time, the relative speed of the magnetic tape 5 and the head 4 in the recording track direction is selected to be 1/4 times, whereby a magnetization pattern having the shortest recording wavelength of 0.9 [μm] is formed on the recording track of the magnetic tape 5.

According to the above configuration, it has to be emphasized rate signal S _RT corresponding to the data rate Yotsute, with emphasis amount corresponding front edge to the data rate of the pre-edge emphasizing circuit selectively information data using Accordingly, it is possible to realize a data recording device capable of forming the same magnetization pattern on the magnetic tape even when the data rates are different.

In the above-described embodiment, the case has been described in which the front edge of the information data is emphasized by using the front edge emphasizing circuit having the differentiating circuit configuration to emphasize the high-frequency component of the information data. For example, a high frequency component of the information data may be emphasized by a circuit means such as a digital filter.In this case, if a circuit means such as a digital filter having different characteristics is selectively used according to the data rate. good.

Further, in the above-described embodiment, the front edge emphasizing circuit is provided when the data rate of the information data is 1/1, 1/2 times, but in addition to this, the data rate is 1/4, 1/8, 1 / 16,
For the case of 1/24 times, a front edge emphasizing circuit corresponding to each case may be provided, and in this case, in addition to the above, the data rate differs for 1/8, 1/16, 1/24 times In some cases, the same effects as those of the above embodiment can be realized.

In the case where information data having a plurality of data rates is selectively recorded as described above, instead of a configuration in which the front edge enhancement circuit having a fixed constant is controlled by switching, the resistance and the capacitor of the front edge enhancement circuit are used. Variable components may be used to control these values according to the data rate. In this case, the overall configuration can be further simplified.

Furthermore, in the above-described embodiment, the case where the present invention is applied to a data recording device that records, for example, observation data and measurement data has been described. However, the present invention is not limited to this, as long as information data can be recorded at a variable speed. It is suitable for wide application to a data recording device capable of recording video signals and audio signals.

H Effects of the Invention As described above, according to the present invention, by emphasizing the high frequency component of the information data with the emphasis amount corresponding to the data rate, even if the data rate is different, the same magnetization pattern can be formed on the magnetic tape. Can be realized.

[Brief description of the drawings]

FIG. 1 is a connection diagram showing an embodiment of a data recording device according to the present invention, FIG. 2 is a characteristic curve diagram showing frequency characteristics of magnetic permeability according to a data rate, and FIG. 3 shows a conventional data recording device. FIG. 4 is a signal waveform diagram for explaining the waveform interference caused by the information data recording pattern. 1, 10 ... data recording device, 2 ... recording amplifier circuit, 3 ...
... Rotary transformer, 4 ... Head, 5 ... Magnetic tape, 11 ... Switching circuit, 12, 13 ... Front edge enhancement circuit.

Claims (1)

(57) [Claims] 1. A data recording apparatus for recording information data having an arbitrary data rate on a magnetic recording medium, comprising: a high-frequency emphasizing means for enhancing a high-frequency component of the information data with an emphasis amount corresponding to the data rate. A data recording apparatus, wherein the same magnetic pattern is formed on the magnetic recording medium even when the information data has various data rates.