SU1026158A1 - Method of magnetic recording and reproducing of digital data - Google Patents

Abstract

THE METHOD OF MAGNETIC RECORDING AND DIGITAL INFORMATION HARDWARE, based on the recording of each binary input information unit by the magnetization difference of one direction, and each binary zero by the opposite direction difference, playing the recorded signal and forming a pulse sequence according to the extreme values of the reproducible signal, followed by a beat of the second section, and then the beat of the second section, each time, the response of the binary signal will be recorded. information that, in order to increase the efficiency of use of magnetic The carrier and fidelity of reproduction of recorded information, when recording alternating tsihs Binary zeros and units of magnetization between adjacent differences, establish a constant at the level of the previous differential, and when recording consecutive zeros or units, the magnetization between differences varies linearly, while recognizing binary zeros and units. during SL reproduction, it is produced by determining the polarity of each isocproduced pulse.

Description

The invention relates to TexHHife computing, in particular to digital data recording equipment.

There is a known method of recording with group coding, in which groups from and from tvols are recoded into groups of fri + AND characters in such a way that in the recorded sequence the number of repeated binary zeros does not exceed a certain miniG / oval number G 3This allows reducing the width of the spectrum of the recorded signal However, the disadvantages of the method are; The number of characters to be written is increased by; compared with the output sequence, which reduces the efficiency of use of the carrier; to implement the method, complex encoding and decoding operations and corresponding equipment are necessary, which reduces the reliability of the recording.

There is a method of recording with phase coding, in which the recording of O the first half of the bit interval is magnetized positively, the second is negative, and during recording the I phase changes by 180 °. When writing a sequence of binary zeros or, units of magnetization drops are 5 times as in the middle of the bit interval and at its borders. When playing, the pulses corresponding to the midpoints of the bit intervals are selected for recognition, and then the I-DC polarity 23 is determined.

The disadvantages of this method are the duration of the intervals between the magnetization differences in the structure of the recording signal is changed twice, which makes the spectrum of the signal sufficiently large and limits the increase in recording density; the shift of the reproduced pulse by a quarter of the bit interval, as a result of distortions in the end-to-end channel or inaccuracy of signal processing in the recording and playback equipment, leads to errors and a decrease in the reliability of recording,

The purpose of the invention is to increase the efficiency of use of magnetic media and the reliability of reproduction of recorded information.

The goal is achieved by the fact that in the method of magnetic recording and reproduction of diffractive information based on the recording of each binary unit of input information by the differential of one direction, and each binary zero: by the difference of the opposite direction, reproduction of the recorded signal and the formation of an extreme sequence values of the reproduced signal with

the subsequent recovery from this sequence of binary information, when recording alternating binary zeros and ones on the ia axis between neighboring differences, is set constant, at the level of the previous differential, and when the records of consecutive zeros and ones, the magnetization between the differences changes linearly, while recognizing binary zeros and units during reproduction are produced by determining the polarity of each reproduced pulse.

The method provides a uniform recording signal structure, because regardless of the input information, the time interval between adjacent magnetization ratios is always equal to the bit interval duration. As a result, the recording signal spectrum is narrow and agrees well with the passband of the through channel, which increases the recording density. One bit of magnetization fell on each bit of input information, and in the method of the prototype - from one of two drops, which also increases the density.

The absence of restrictions on the temporal distortions of the reproduced signal, caused by character recognition by determining the polarity of each reproduced pulse, makes it possible to increase the reliability of reproduction of the recorded information.

FIG. 1 is a block diagram; FIG. 2 is a time diagram; FIG. 3 is a functional diagram of the modulator of the recording device.

The proposed method is most effective with a linear change in the magnetization between adjacent ratios when recording consecutive O or 1.

To implement the proposed method, modulator 1, the functional diagram of which is shown in FIG. 3, is supplied with an uninterrupted digital sequence in the form of a binary code of FIG. 2a), accompanied by a sync pulse (FIG. 2), ia output of the modulator 1 when recording alternate O and 1 form rectangular voltage drops, and when recording consecutive O or 1, sawtooth. Next, the signal is fed through the recording amplifier 2. To the recording head 3, recording is made on a moving medium with magnetic media. The reproduction signal in FIG. 2d) is removed from the reproducing head 4. The reproduced signal is fed to the playback amplifier 5 and then to the modulator b, which determines the polarity of each reproduced pulse and demodulates the corresponding code symbol. In the modulator (Fig. 3)) the delay element 7 delays the information signal for a time equal to the period of the clock pulses, the controlled generator 8 forms a sawtooth signal) the decoder 9, depending on the input two-digit binary combination, generates a sawtooth signal . The outputs of the resolution signal, the elements OR 10 and ZI-OR 11, are used to switch signals. Each is in demand: the input pulse is information, and therefore no additional synchronization is required. The time intervals between replicable pulses are constant, so when one or several pulses fall out, the error is easily detected. The method is especially effective at low speeds of movement of the magnetic carrier.

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Claims (1)

METHOD FOR MAGNETIC RECORDING AND PLAYBACK OF DIGITAL INFORMATION, based on the recording of each binary. Unit of input information by the difference of the magnetization of one direction, and each binary zero by the difference of the opposite direction, playback of the recorded signal and the formation of a pulse sequence from the extreme values of the reproduced signal with subsequent restoration from this sequence * information about the fact that, in order to increase the efficiency of using magnetic the media and the accuracy of reproducing the recorded information, when recording alternating Binary zeros and units of magnetization between adjacent drops, they are set constant at the level of the previous difference, and when recording successive zeros or ones, the magnetization between drops is linearly changed, while binary zeros are recognized and Units during reproduction are produced by determining the polarity of each reproduced impulse. output figure 1 sl 1026153