SU1223293A1 - Method of magnetic recording of digital information - Google Patents

Abstract

This invention relates to methods for magnetic recording of digital information. The circuit of the invention is an increase in the amount of recorded information by increasing the recording density. Elements OR 10 - 12 form the first three auxiliary signals. The input information signal (IC) is inverted by block 13 and from its output goes to divider 14 by two, then paraphase control signals (PS) are fed to the combined second inputs of the And 15-20 elements, respectively, and to the first inputs - the first auxiliary signals (BC) . On elements 15-20, the first aircraft are multiplied with each PS and 6 second aircraft are formed. The outputs of the AND elements are connected to the adder-exchanger 21, the output of which receives a control signal, in which the time differences between different-field voltage drops correspond to the sum of two adjacent time intervals of the input IC. The block 21 is connected to a sawtooth voltage former 23, a recording amplifier 24 and a recording head 25. 2 Il. sl 25 to y soy with 100 f1 / g.2

Description

The invention relates to magnetic recordings, in particular to methods for magnetic recording of digital information.

The purpose of the invention is to increase the amount of recorded information by increasing the recording density.

The method of magnetic recording of digital information is carried out by converting the information signal into pulse sequences of rectangular voltage drops with the same amplitude and duration corresponding to the duration of the information signal, forming a summation-subtraction of the pulse sequence of rectangular voltage drops with alternating polarity, in which absolute the magnitudes of the voltage amplitude at each time interval are inversely proportional to the durations of these the intervals from which the recording signal is formed as a sequence of sawtooth voltage drops, alternating polarity and equal amplitude, this voltage vary linearly at each time interval, after which magnetic magnetic recording is made with magnetic biasing or constant In addition, in pairs, the pulse sequences of rectangular voltage drops with the same amplitude and with the same amplitude are summed in pairs; they form paraphase pulse values Measurements by dividing the information signal by its negative differences, each of which is multiplied with each result of the summation of the pulse sequences of the rectangular voltage drops, the results of the multiplication with each of the paraphase signals are summed up, and the results of the summation are subtracted from one another. recording signal is produced by changing the polarity of the summation-subtraction result, the polarity of the recording signal is alternated between changes of the field p the result of the summation is the reading of the positive differential of the information signal.

Figure 1 presents timing diagrams for explaining the operation of the proposed method for the case when

the input information signal is represented by a three-interval (p 3) pulse sequence of rectangular voltage drops of the IMF method, modified phase modulation (IMF); Fig. 2 is a block diagram of a device for implementing the proposed method.

To the input 1 of the device comes

an input signal (Fig. 1A) with durations of time intervals IT, 1.5 T and 2 tons, and to synchronization input 2 - a synchronous frequency with a period of 0.5 T, In block 3, the separation and distribution

time intervals, the input signal is divided into intervals of the same duration and polarity, which through outputs 4.5 (IT intervals), 6 and 7 (1.5 T intervals), 8 and 9

(2T intervals) are fed to the inputs of the elements OR 10-12, which form the first three auxiliary signals (Fig. 2, signals B, C and D) having the first (high) voltage level, when in the input information signal (Fig. 2A) the intervals have a predetermined duration (IT, 1.5T or 2T), and the second (low) voltage level, when the interval has other duration values.

The input information signal is inverted by the inverter 13 and, from its output (FIG. 2D), is supplied to frequency divider 14 by two, from the direct and inverse outputs of frequency divider 14 by two, paraphase control signals (FIG. 2E) are fed to combining 1st second inputs elements And 15, 17, .19 and 16, 18, 20, respectively, and the first auxiliary signals arrive at the pairwise combined first inputs of elements And 15 and 16, 17 and 18, 19 and 20.

On elements 15-20, the first auxiliary signals are multiplied (Fig. 2B, C and D) with each of the paraphase control signals (Fig. 2E, G), and 6 second auxiliary signals are formed at the outputs of these elements (Fig. 2, signals 3, I, K, M and H).

The outputs of the elements And 15 - 20 connected to the inputs of the adder-subtractor 21, made on the operational amplifier 22, which performs the summation-subtraction of the second auxiliary signals with scale

coefficients are inversely proportional to 1; O1 are the durations of the corresponding time intervals of the input information signal (the scale factors are determined by the appropriate choice of resistors R1, R2, R3 R4). At the output of the adder-subtractor 21, a control signal (Fig. 2 O) is obtained, in which the time differences between the different polarity voltage drops correspond to the sum of two adjacent time intervals of the input information signal, and the absolute magnitudes of the voltage amplitude are inversely proportional to the duration of each of intervals of the input signal, forming a given time interval control kntz signal. The control signal has a stepped form when its time intervals are formed by unequal duration by adjacent intervals of the input information signal.

The output of the adder-subtractor is connected to the sequentially connected driver (generator) of sawtooth 23, recording amplifier 24 and recording magnetic keyboard 25. The driver 23 generates a recording sawtooth signal (Fig. 2P), in which at the control signal boundaries between the different polarity switches ( Fig. 2 O), the amplitude has zero values, and the maximum values of the amplitude, the same in absolute value for opposite polarity of the sawtooth signal, correspond to the boundaries of the input information intervals signal, the formation of the time interval of the control signal.

Recording amplifier 24 provides for the recording current of the required value, which coincides in form with

with

using a sawtooth recording signal (FIG. 2P) which is used to record onto a carrier. Elements and magnetism signals in Figures 1 and 2 are conventionally not shown.

Reproduction of information recorded by the proposed method includes the operations of differentiation, amplification and correction, the formation of signals corresponding to the peaks (null intersections) of differentiated and, undifferentiated reproduction signals, the formation of them

sync signals and decoding information.

The recording sawtooth signal according to the proposed method, as can be seen from the plot of FIG. 2P, transfers 4 bits of information in a period, whereas the recording signal by a known method, shown for comparison in FIG. 2P, carries only two bits of information in the period of this signal.

The use of the invention allows to significantly increase the amount of recorded information due to the increased density recorded

Claims (1)

Invention Formula 25 thirty The method of magnetic recording of digital information by converting an information signal into pulse sequences of rectangular voltage drops with the same amplitude and duration, corresponding to the duration of the information signal, forming a summation-subtraction of a pulse sequence of rectangular voltage drops with alternating polarity, in which the absolute values of the voltage amplitude at each time interval are inversely proportional to the duration values of these intervals fishing, of which sequence is formed as a recording signal transferred pad 35 voltage sawtooth ,, alternating polarity and equal; amplitudes, and this voltage varies linearly at each time interval, after which recording onto magnetic recording media with high-frequency or direct current biasing, characterized in that, in order to increase the amount of recorded information by increasing the recording density, pairs are summed pulse sequences of rectangular voltage drops with the same amplitude and with the same duration, 50 form paraphase pulse sequences by dividing the information signal by its negative differences, each of which is multiplied with each result of summing the 55 pulse sequences of rectangular voltage drops, and the results of the multiplication with each of the paraphase signals are summed up, and 40 45 s the results of the summation subtract one from the other, and the direction of change in the signal of the recording is made according to the change in the polarity of the result of the summation – subtraction, 2232936 The polarity of the recording signal is carried out between changes in the polarity of the sum-subtraction result on the positive differences of the information signal. Compiled by V.Dobrovolsky Editor S.Patrusheva Tehred i.Popovich Proofreader E Roshko Order 1720/55 Circulation 543Subscription .VNIIPI State, USSR Committee on Inventions and Discoveries 113035, Moscow, Zh-35, Raushsk Ha6i. D. 4/5 Branch PPP Patent, Uzhgorod, st. Project, 4