RU2054797C1 - Pulse repetition rate selector - Google Patents

Abstract

FIELD: pulse technique. SUBSTANCE: device has delay line 1, first-pulse selecting unit 2, AND gates 3, 5, 10, flip-flops 4, 12, 13, OR gates 6, 11, delay element 7, strobe shaping unit 8, scaling unit 9, pulse shaper 14, input and output buses 15 and 16 with appropriate connections. EFFECT: improved design. 2 dwg

Description

 The invention relates to a pulse technique, in particular to selectors for the period following, and can be used in automation and computer technology to isolate signals against interference.

Known pulse selector containing a conversion device, a device for extracting the first pulse, an OR element, a delay element, a device for forming gates and an element And [1]
The disadvantage of this device is the large time allocation of the breeding sequence in the presence of periodic interference at the input.

Known pulse selector for the repetition period, comprising a device for extracting the first pulse, two triggers, an OR element, a delay device, a gate generator, an element And a recounting device [2]
This selector has insufficient speed and noise immunity under the influence of periodic interference.

Also known is a pulse selector comprising a first pulse extraction device, an OR element, a delay device, a strobe driver, an And element, a conversion device and two triggers [3]
However, this selector also has insufficient speed when exposed to periodic noise on its input.

The closest in technical essence to the invention is a pulse selector for the repetition period, comprising a conversion unit, a delay line, the first and second AND elements, a first trigger and a serially connected first pulse extraction unit, a first OR element, a delay element, a strobe block, and a third element And, the output of which is connected to the first input of the conversion block, the output of the selector and the second inputs of the block forming the gates and the first OR element, and the second input to the input of the selector, the first inputs of the block the creation of the first pulse, the delay line and the first element And, its second input connected to the output of the delay line, and the output with the first input of the second element And, the second input connected to the output of the first trigger, and the output connected to the first input of this trigger and the third input of the first element OR, by its fourth input of the delay element connected to the output, the second input of which is connected to the second inputs of the first pulse selection unit, the delay line and the first trigger, as well as the first output of the conversion unit, the swarm output of which is connected to the third input, and the second input to the output of the strobe block [4]
This selector has poor performance when there is a large number of periodic interference at the input.

 This is because the prototype selector is set up according to the very first pulse formed at the output of the additional selector restart channel.

 The aim of the invention is to reduce the time of selection of the selected sequence under the influence of a large number of periodic interference due to the setting of the selector on the selected sequence according to the pulse received in the strobe generated by the pulse from the output of the additional channel of the selector performing preliminary selection.

 To this end, in the pulse selector for the repetition period containing the conversion unit, the delay line, the first and second AND elements, the first trigger and the first pulse extraction unit, the first OR element, the delay element, the strobe generation unit and the third AND element, the output of which connected to the first input of the conversion block, the output bus and the second inputs of the block forming the gates and the first OR element, and the second input of the third element AND is connected to the input bus, the first inputs of the block selection of the first pulse, l the delay line and the first AND element, the second input of which is connected to the output of the delay line, and the output to the first input of the second AND element, the second input of which is connected to the output of the first trigger, and the output to the first input of the first trigger and the third input of the first OR element, the fourth input which is connected to the output of the delay element, the second input of which is connected to the second inputs of the block selection of the first pulse and the delay line, as well as to the first output of the conversion unit, the second output of which is connected to the third input of the block is formed gates, and the second input to the output of the strobe forming unit, a second OR element, a second and third triggers and a pulse shaper are additionally introduced, the first input of the second trigger connected to the output of the first pulse allocation unit, the second input to the output bus, and the third input to the output the second element And and the first input of the third trigger, the second input of which is connected to the output of the second trigger, the third input to the output of the strobe block, and the output is connected to the input of the pulse former, the output of which is connected to the first ode second OR gate, the second input of which is connected to first output sealer unit, and an output to a second input of the first flip-flop.

 In FIG. 1 shows the structural electrical circuit of the selector; figure 2 diagrams explaining the operation of the selector.

 The pulse selector for the repetition period contains a delay line 1, a first pulse allocation unit 2, AND elements 3,5, 10, triggers 4, 12, 13, OR elements 6, 11, a delay element 7, a gate formation unit 8, a conversion unit 9, pulse shaper 14.

 Input pulses are fed to input 15, output pulses are removed from output 16.

 The first pulse extraction unit 2, the OR element 6, the delay element 7, the strobe forming unit 8, and the And element 10 are connected in series.

 The output of the element And 10 is connected to the first input of the conversion unit 9, the output of the selector 16 and the second inputs of the OR element 6, the gate generator 8 and the trigger 12.

 The second input of the element And 10 is connected to the input of the selector 15 and the first inputs of the block selection of the first pulse, element And 3 and the delay line.

 The output of the delay line is connected to the second input of the And 3 element, the output of which is connected to the first input of the And 5 element.

 The second input of the And 5 element is connected to the output of the trigger 4, the first input of which is connected to the first input of the trigger 13, the third input of the trigger 12, the output of the And 5 element and the third input of the OR 6 element.

 The fourth input of the OR element 6 is connected to the output of the delay element 7, the second input connected to the second inputs of the delay line 1, the block selection of the first pulse, the element OR 11 and the first output of the conversion unit 9.

 The second output of the conversion unit 9 is connected to the third input of the gate generator 8, and the second input to the output of this driver, as well as the third input of the trigger 13, the second input of which is connected to the output of the trigger 12, and the output to the input of the pulse generator 14. The output of the latter is connected to the first input of the OR element 11, the output connected to the second input of trigger 4.

 The first input of the trigger 12 is connected to the output of the allocation unit of the first pulse.

 As the delay line 1, for example, a similar prototype delay line can be used. As a block selection of the first pulse 2 can be used, for example, a similar block of the prototype.

 The delay element 7 should not have a lock from restarting and at each start it should count the delay again.

 As a delay element 7, for example, counters can be used.

 The device forming the gates 8 may be, for example, similar to the corresponding device of the prototype.

 As a pulse shaper 14, for example, a single vibrator can be used.

 The remaining elements of the device are logical elements of a potential type.

 As the conversion unit 9 can be used, for example, a similar unit of the prototype.

 The time diagrams (figure 2) show: I, III pulses of periodic interference; II pulses of breeding sequence; IV pulses at the output of the element And 3; V pulses at the output of the first pulse allocation block; VI pulses at the output of the block forming gates; VII signal at the output of trigger 4; VIII signal at the output of trigger 12; IX signal at the output of trigger 13; X pulses at the output of the pulse shaper 14; XI pulses at the output of the 16 selector; XII pulses at the output of the element And 3 prototype; XIII pulses at the output of the block forming gates 8 of the prototype.

 Consider the operation of the proposed selector.

 Let at its input 15 is fed a pulse train consisting of a selectable sequence (FIG. 2 II) and periodic interference pulses (FIG. 2 I, III).

 The first pulse a (Fig. 2 I) of the input sequence that does not belong to the selectable sequence is allocated by block 2 (Fig. 2 V) and sets the trigger 12 to the zero state (Fig. 2 VIII), and also, passing through the OR element 6, starts the delay element 7, which delays this pulse by the value of Tt / 2, where T is the period of succession of the selected pulses; t strobe width.

 The pulse delayed by element 7, when starting the strobe forming unit, determines the start of the strobe generated by block 8 for the next pulse of the input sequence.

 In addition, this pulse passes through the element OR 6 and restarts the delay element 7, thereby determining the beginning of the next strobe relative to the leading edge of the previous one.

 When coinciding on the element And 10 of the formed strobe (FIG. 2 VI) with the input pulse b (FIG. 2 III) supplied to the other input of the element And 10, the output pulse with (FIG. 2 XI) is generated at the output of this element, which the leading edge confirms the zero state of trigger 12, resets the conversion unit 9 and the gate generator 8, breaking the gate, on the trailing edge of which the state of trigger 12 is overwritten into trigger 13 (in this case, overwriting the zero state).

 In addition, the output pulse with (figure 2 XI), passing through the element OR 6, restarts the delay element 7, thereby determining the new position of the next gate relative to the input pulse.

 The arrival of the output pulse on the OR element 6 coincides with the arrival of the pulse on this element from the output of the And 5 element, which is formed as a result of the coincidence of the pulse of the input sequence on the And 3 element with the input pulse delayed in delay line 1 for a time equal to the selected period T. Formed at the output of the And 3 element, the pulse passes to the output of the And 5 element and, with its trailing edge, resets trigger 4, prohibiting the passage of subsequent pulses from the output of And 3 element to the output of And 5 element, and also sets trigger 12 to single, and trigger 13 to the zero state.

 Due to the simultaneous arrival of the pulse from the output of And 5 and the output pulse to the element OR 6, as well as the fact that the trigger 4 is reset and the passage of pulses from the output of the And 3 element through the And 5 element, the pulse from the output of the And 5 element will not affect the operation of the selector.

 In the pulse formed by pulse b (FIG. 2 III), gate d (FIG. 2 VI) did not enter the input sequence pulse, since gate b does not belong to the selected sequence.

 On the trailing edge of strobe d (FIG. 2 VI), the single state of trigger 12 is rewritten to trigger 13 (FIG. 2 VIII, IX) and the state of the recalculation block 9 changes.

 The difference in the signal at the output of the trigger 13 triggers the pulse shaper 14. The pulse generated at the output of the shaper 14 (Fig. 2 X), passing through the element OR 11, sets the trigger 4 in a state that allows the passage of pulses through the element And 5 from the output of the element And 3 (FIG. 2 VIII).

 The pulse e (Fig. 2 IV), passed through the open element And 5, puts the trigger 4 in a state that closes the element And 5 (Fig.2 VII) and sets the trigger 12 to one, and the trigger 13 to zero (Fig.2 VIII IX).

 In addition, this pulse, passing through the element OR 6, restarts the delay element 7.

 Pulse j (FIG. 2 II), belonging to the selected sequence, gets into the gate f generated by the pulse e (FIG. 2 VI).

 The leading edge of the pulse j resets the recounting block 9, the block forming the gates 8, restarts the delay element 7, and also transfers the trigger 12 to the zero state (Fig. 2).

 Since the trigger 13 is in the zero state, then the state of the gate f does not change its state, a difference is not formed at its output, therefore, the pulse of setting the trigger 4 to a state that allows the passage of pulses through the And 5 element, at the output of the shaper 14 is not formed.

 In the future, the formation of gates in the selector is made from pulses that hit the gate on the element And 10.

 When the pulse is skipped, the output pulse is not formed and the strobe is fully formed.

 The trailing edge of the strobe confirms the zero state of the trigger 13 (trigger 12 is in the zero state) and the state of the counting unit 9 changes, which in turn changes the operation mode of the strobe forming unit 8, so that with each successive missed pulse, the width of the strobe generated by the strobe unit 8 increases by t. Since the delay element 7 is not restarted by the output pulse due to the absence of the latter, the leading edge of these gates with each consecutively missed pulse is shifted by t / 2 from the previous gate.

 The maximum permissible number of consecutively missed pulses can be any equal to m.

 This number determines the coefficient of the conversion block 9.

 Any output pulse generated at the output of the selector 16 before the number of missed pulses was m, resetting the recount unit 9, sets it to its initial state.

 If there occurs a consecutive skipping of m + 1 selectable pulses, the recounting unit 9 is overflowed.

 The overflow pulse of this block resets the first pulse allocation block 2, delay line 1, delay element 7, and also, through element OR 11, transfers trigger 4 to a state that allows the passage of the pulse from the output of element And 3 to the output of element And 5.

 The selector changes to the initial state.

 Note that the pulses of the additional channel for restarting the selector (pulses from the output of the And 5 element) do not interfere with the operation of the selector, if the pulses of the input sequence enter the strobe on the And 10 element.

 The diagrams of figure 2 XII and XIII presents the work of the prototype selector, working in similar conditions with the proposed device.

 For the case shown in figure 2, with the conversion factor of the prototype selector block equal to 1, the prototype selection time of the selectable sequence turned out to be two periods longer than the selection time of the selectable sequence by the proposed selector.

 Thus, the increase in performance under conditions of periodic interference in the proposed selector is ensured by the fact that the proposed selector is tuned according to the pulse received in the strobe generated from the pulse generated at the output of the additional channel for restarting the selector, which reduces the time of selection of the selected sequence.

 The greatest efficiency of the proposed selector is achieved when working with periodic interference having a period close to the selectable one, and with an increase in the number of interference acting on the input of the selector.

Claims (1)

 PULSE SELECTOR BY THE FOLLOW-UP PERIOD, containing a conversion unit, a delay line, a first, second AND element, a first trigger and a serially connected first pulse extraction unit, a first OR element, a delay element, a strobe forming unit and a third AND element, the output of which is connected to the first input the conversion unit, the output bus and the second inputs of the gate formation unit and the first OR element, and the second input of the third AND element is connected to the input bus, the first inputs of the first pulse allocation unit, the delay line and the first AND element, the second input of which is connected to the output of the delay line, and the output to the first input of the second And element, the second input of which is connected to the output of the first trigger, and the output - to the first input of the first trigger and the third input of the first OR, the fourth input of which connected to the output of the delay element, the second input of which is connected to the second inputs of the allocation unit of the first pulse and the delay line, as well as to the first output of the conversion unit, the second output of which is connected to the third input of the strobe forming unit, and in the second input is to the output of the strobe forming unit, characterized in that the second OR element, the second and third triggers and the pulse shaper are additionally introduced into it, the first input of the second trigger connected to the output of the first pulse allocation unit, the second input to the output bus, and the third input is to the output of the second And element and the first input of the third trigger, the second input of which is connected to the output of the second trigger, the third input is to the output of the strobe block, and the output is connected to the input of the pulse former, the output of which is connected to the first input of the second OR element, the second input of which is connected to the first output of the conversion unit, and the output to the second input of the first trigger.

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