SU1506527A1 - Level-integral shaper - Google Patents

Abstract

The invention relates to a pulse technique and can be used in magnetic recording and reproducing devices, where it is necessary to recognize bell-shaped or sinusoidal pulses under conditions of a strong interference field when the power interference power is close to the power of the useful signal. The purpose of the invention is to improve noise immunity by eliminating time shifts and loss of information signals (ICs). The driver contains a limiter 2 on the level of positive half-waves of the input signal, a limiter 3 on the level of negative half-waves of the input signal, elements AND 4, 6, 13, 14, pulse generator 7, counters (C) 8, 10-12, elements OR 15-17, The RS-trigger 18, a decoder 19. The capacitance C 10, 11 is of the same order and constitutes 20-50 of the capacitance C 8. The frequency of the generator 7 is 100-1000 times higher than the frequency of the IC. When the shaper is operating in the IC area, it is advantageous to fill C 8 and 10, dialing the required number of pulses required to form the IC. After dialing a certain number due to pulsed noise at the output of C 11, pulses appear that periodically reset C 10 and 8 to their original state, preventing the accumulation of spurious signals in them. The additional reset C 11 forms a small protection zone, preventing a possible reset of the already practically formed output signal at C 8. As a result, possible temporary distortions in the position of the IC fronts are eliminated. 2 Il.

Description

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fur, when the power of interference is close to the power of the useful signal. The purpose of the invention is to improve noise immunity by eliminating time shifts and sending information signals (ICs). The shaper contains a limiter 2 on the level of positive half-waves of the input signal, a limiter 3 on the level of negative half-waves of the input signal, elements AND 4,6, 13,14, generator 7 pulses, counters (C) 8,10-12, elements OR 15-17, RS-flip ger 18, decoder 19. Capacity C 10, 11 is of the same order and is 20-50 parts of capacity C 8. Generator frequency 7 is 100-1000 times higher than frequency

follow IC. When the shaper is operating in the IC area, it is advantageous to fill C 8 and 10, dialing the required number of pulses required to form the IC. After dialing a certain number due to pulsed noise at the output of C 11, pulses appear that periodically reset C 10 and 8 to their original state, preventing the accumulation of spurious signals in them. The additional reset C 11 forms a small protective zone, preventing a possible reset of the already practically formed signal at C 8. As a result, possible temporary distortions of the position of the fronts of IC 2 are eliminated

The invention relates to a pulse technique and can be used mainly in magnetic recording and reproducing devices, where it is necessary to recognize pulses of a bell-shaped or synusrial shape under conditions of a strong interference field when the power interference power is close to the power of the useful signal.

The purpose of the invention is to increase noise immunity by eliminating time shifts and loss of temporal signals.

FIG. 1 shows a functional diagram of the imager; in fig. 2 - time diagrams that show his work.

The driver contains an input terminal 1, a limiter 2 for the level of the adjective half-waves of the input signal, a limiter 3 for the level of negative half-waves of the input signal

voltage, element 4, inverter 5, element 6, pulse generator 7, counter 8, output terminal 9, counters 10-12, elements 13 and 14, elements OR 15-17, RS flip-flop 18, decoder 19, diodes 20 and 21.

The inputs of the limiters 2 and 3 are connected to the input terminal 1, the outputs through the diodes 20 and 21 are connected to the input of the inverter 5 and one input of the element 4, the other input of which is connected to the output of the element 13 and one input of the element 6, the other input of which is connected to inverter output 5, you

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the pulse generator 7 is connected to one input of the elements 13 and 14, the other inputs of which are connected to the corresponding outputs of the RS flip-flop 18, the outputs of the elements 4 and 6 are connected to the inputs of the corresponding counters 10 and 11, the installation inputs of which are connected to the outputs of the corresponding elements OR 15 and 17, the output of the counter 11 is connected to one input of the elements OR 15 and 16, the other inputs of which are combined with the first input of the element OR 17, one input of the RS flip-flop 18, the output terminal 9 and connected to the output of the last digit of the counter 8, the setting the second input of which is combined with the output of the element OR 16, another input of the RS flip-flop is connected to the output of the counter P12, the output of the element AND 14 is connected to the input of the counter 12, the output of the counter 10 is connected to the second input of the element OR 17 and the input of the counter 8, the outputs of the first bits which is connected to the inputs of the decoder 19, the output of which is connected to the third input of the element OR 17.

The shaper works as follows.

The input signals 22 of sinusoidal or bell-shaped form, together with noise, are fed to the inputs of limiters 2 and 3, one of which has an inverse output. Limiters 2 and 3 delay interference with an amplitude not exceeding the limit levels.

The pulses from the generator 7, whose pulse frequency is 100-1000 times higher than the frequency of the information signals, depending on the state of the RS flip-flop 18 are passed to the input of the counter 12, or the inputs of the counters 8,10,11. In the case of the arrival of pulses to the counter 12, by filling it, a signal is generated at the output that switches the RS flip-flop 18, and the latter, through element 13, supplies generator 7 pulses to the inputs of elements 4 and 6, after which counters 10 , 8, 11. The capacity of the counters 10 and 11 is of the same order and is approximately 20-50 parts of the capacity of the counter 8.

When the driver is operating in the area of the information signal 23, counters 10 and 8 are predominantly filled, dialing the necessary number of pulses required to generate information signals 2A. The shaper is designed to operate in this zone with a relatively coarse t and negative interference pulses that change the amplitude of the useful signal 25 to a level below the limit level. The capacity of the counter 11 is selected on the basis that a few negative interference pulses do not lead to its full filling and the appearance of a signal at its output.

Since, due to the effect of the useful signal, the number of pulses coming from element 1A is much larger than the number of pulses coming from element 6 and the counters 10 and 11 of the same order, the output of counter 10 periodically appears the pulses 26 and 27, which, through the OR element 17, flush the contents of the counter I into O. Therefore, short interfering pulses, although recorded by the counter 11, do not affect the operation of the former as a whole.

When the shaper operates in the zone between the useful signals, where the probability of errors due to interference in the form of psx pulses 22 is greatest, the number of generator pulses arriving at counter 11 exceeds the number of pulses, since counters 10 and 8 the signal is at zero level (absent). After dialing a certain number due to the den

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target levels at the output of counter 11, pulses appear that, through the elements OR 15 and 16, periodics 1, reset counters 10 and 8 to their original position, preventing the accumulation of spurious signals 28, 29 in them.

To increase the noise immunity, when a certain number of pulses are dialed by a counter 8, close to the number at which the information signal appears, a decoder 30 is generated on the decoder 19, reset-ju (counter 11) generates a small response signal. the zone, preventing a possible reset of the practically formed output signal on the counter 8, if at this moment a negative disturbance passes, is sufficient to trigger the counter 11.

The information signal at terminal 9 of the driver generates through the elements OR 15-17 the reset of all counters and at the same time sets the RS flip-flop 18 to the position of the protective gap 12 by the counter, simultaneously through the element 13 and blocking the arrival of pulses 31 and 32 of the generator 7 to the counters 8, 10 11. This blocking of counters is based on the position that the next information signal cannot reach a predetermined time and prevents a possible distortion of the time position of the next information signal or even left not a false one, since it is in this zone that the ratio of the residuals of the useful signal and interference is most uncertain.

The proposed level-integrated driver, despite the presence of a continuously operating obstacle field, both in the zone of useful signals and in the areas of their action ensures reliable allocation of information signals.

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Claims (1)

Invention Formula Level-integral driver, content limiter on the level of positive half-waves of the input signal, limiter on the level of negative half-waves of the input signal, the inputs of which are combined and connected to the input terminal of the imager, pulse generator, the output of which is connected to the first inputs of the first and second elements, And the output of the second element And connected to the input of the first counter, the output of which is connected to the first input of the trigger, the outputs of which are connected to the second inputs of the corresponding first and second elements And, characterized in that, in order to improve noise immunity by eliminating time shifts and loss of information signals, an inverter, the first and second diodes, the third and fourth elements AND, the first, second and third elements OR, the second, the third and fourth counters, the trigger is made with an RS-type trigger, the first input of which is the setup input, the outputs of the limiter by the level of positive half-waves of the input signal and the limiter by the level of negative half-waves of the input signal through the corresponding ue diodes are connected to the input of the inverter and the first input of the third I .. i And ill i jy ii iil: nn Compiled by V. Butin Editor S. Latrusheva Tehred M. Khodanych Order 5445/54 Circulation 884 VNIIPI State Committee for Inventions and Discoveries at the State Committee on Science and Technology of the USSR 113035, Moscow, Zh-35, Raushsk nab. 4/5 element And, the second input of which is connected to the output of the first element And and to the first input of the fourth element And, the output of the inverter is connected to the second input of the fourth element And, the outputs of the third and fourth elements And are connected to the counting inputs of the corresponding second and third counters, the installation inputs of which are connected to the outputs of the corresponding first and second elements OR, the output of the last digit of the fourth counter is connected to the reset input the trigger, the first inputs of the first, second and third elements OR and the output terminal of the driver, the output of the second counter is connected to the input of the fourth counter and the second the input of the second element OR, the output of the third counter is connected to the second inputs of the first and third elements OR, the output of the third element OR is connected to the installation input of the fourth counter, the outputs of which are connected to the inputs of the decoder, the output of which is connected to the third input of the second element FlTDi. niniiiiffliih ii m M : i I MM n Proofreader T. Paly Subscription