SU471602A1 - Method of recording and reproducing digital information - Google Patents

Description

one

The invention relates to instrumentation and can be used in magnetic recording equipment, where a wire or a tape is used as a magnetic carrier.

Methods are known for recording digital information that is an alternation of clock and information pulses, where the latter are represented as symbols. The location of the pulses between each other at a fixed equal distance is also known, which makes it possible to have an idea of the quantitative state of the service and auxiliary information signals at each particular time instant. But all such technical solutions are designed for a magnetic carrier moving quite uniformly in the path of the magnetic recording apparatus. In the case of a non-uniformity in the movement of the carrier, the reliability decreases.

The purpose of the invention is to increase the reliability of reproducible information with an unevenly moving magnetic carrier.

For this, according to the proposed method, when recording, symbols are used to divide and fix into two unequal parts the time interval between adjacent clock pulses, after which the sign of this symbol is determined. And when playing a similar definition of the sign

the symbol is produced by comparing the values of unequal time intervals, and the clock pulses and symbols are recorded by the opposite of the polarity of the carrier magnetization.

The drawing shows a diagram explaining the proposed method. When recording information from the clock signals, which are represented by clock pulses, and

from the information symbols they form a sequence of signals (diagram a), in which symbol 1 corresponds to two of the three parts between clock pulses, the first of which is denoted by Gj of the second TZ, and the actual

symbol O corresponds to sections T and 7.}, where TI T and the Pulse sequence shown in diagram a are recorded as magnetization differences (diagram b, where the pulse of the clock frequency corresponds to a difference of negative polarity and the symbol is positive. The sum is and the sum is the clock interval. The magnetization differences are converted when the pulses are reproduced into signals (Figure 8), from which the pulses corresponding to the polarity of the signal (diagrams r and (3) represented by in diagram 8. Next, compare the pulses of diagrams g and

d, for example, by subtracting and depending on the sign (diagram e) of the value obtained after subtracting the second interval from the first (or vice versa), form pulses corresponding to symbols 1 and О (diagrams and Е к) of the recorded binary code. At the same time form a sequence of pulses of the clock frequency (chart m). As a result of recording and reproducing digital information, its reliability is quite high and with an uneven speed of movement of the magnetic carrier. The method of recording and reproducing digital information on magnetic media, based on the formation of a sequence of clock and information pulses, the latter of which are represented as symbols, followed by a change in the current of 5 10 15 20 recordings and the magnetization of the carrier upon receipt of pulses of the specified sequence, as well as the character of a symbol by determining in the process of reproduction the intervals between the corresponding signals, characterized in that, in order to increase, To reproduce information from an unevenly moving magnetic carrier, when recording by a symbol, the time interval between adjacent clock pulses is divided and recorded into two unequal parts and the sign of the same symbol is determined, and during playback, a similar definition of the sign is made time, while the clock pulses and symbols are recorded opposite to them in polarity by the differences in the magnetization of the carrier.

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