RU82881U1 - COMPLEX FORM PULSE DURATION METER - Google Patents

Abstract

An irregular pulse meter with a normalizing driver and a serially connected RS-trigger and a time-code converter whose output is the output bus of the device, the first input of the normalizing driver is connected to the input bus, characterized in that, in order to improve performance, they are introduced inverter, comparator, first coincidence cascade, second coincidence cascade, reversible counter, code-voltage converter, voltage amplifier and pulse shaper, with the input bus connected to the first input of the comparator, the direct output of which is connected to the first input of the first coincidence stage, the second input of which is the inverter input, the second input of the second coincidence stage and connected to the target strobe bus, and the output of the first coincidence stage is connected to the counting (summing) input of the reversible counter , the subtracting input of which is connected to the output of the second coincidence stage, the first input of which is connected to the inverse output of the comparator, and the third input is combined with the third input of the first stage with drops and is connected to the reference frequency bus, the output of the code-voltage converter is combined with the second input of the comparator and connected to the input of the voltage amplifier, the output of the voltage amplifier is connected to the second input of the normalizing driver, the output of which is combined with the S-input of the RS-trigger and connected to the input of the driver pulses, the output of which is combined with the R-input of the RS-trigger and the R-input of a reversible counter, the output of which is connected to the input of the code-voltage converter, the first input of the normalizing driver is connected to the first

Description

The utility model relates to radio metering and pulsed technology and can be used in devices for accurate measurement of pulse duration of complex shape, for example, in the analysis of radar video pulses and electrocardiograms.

A known pulse width meter containing a normalizing driver, executed on a Schmitt trigger, and a time-code converter (see. Pulse duration meter. Accent. UK application No. 1274402, 05.17.1972, G04F 11/08). Due to the large threshold of the Schmitt trigger (about 1.4 V), this meter does not allow measuring the duration of pulses with a small amplitude at the level of 0.5U _m . It has low accuracy in measuring pulses of complex shape - each pulse surge exceeding the threshold of the Schmitt trigger is measured as a separate pulse. There is also known a device for measuring the duration of pulses, containing a shaper of start-stop pulses, a trigger, a time-code converter and a pulse selection circuit with a minimum duration (see Device for measuring pulse duration. USSR author's certificate No. 516187, Bull. No. 20, 1976, H03K 5/20). This device does not provide the formation of start-stop pulses at a level of 0.5 U _m , which leads to large measurement errors. In addition, when applying pulses of complex shape to its input, only emissions with a minimum duration will be evaluated.

The closest in technical essence to the proposed one is a pulse duration meter of complex shape (see Device for measuring pulse duration. USSR Author's Certificate No. 1174898, Bull. No. 31, 1985), which is adopted as a prototype.

The functional diagram of the prototype device is shown in figure 1, where the following notation is introduced:

1 - delay line;

2 - normalizing shaper;

3 - shaper start pulses;

4, 14 and 20, the first, second and third RS-trigger;

5 - shaper of stop pulses;

6 - time-code converter;

7 - adaptive shaper;

8 - a comparator;

9 and 21 - the first and second element of coincidence;

10, 16 and 22 first, second and third counter;

11 - code-voltage converter;

12 - voltage divider;

13 and 19 - the first and second digital shaper;

15 and 17, the first and second coincidence element;

18 - a logical element 2 AND-OR-NOT.

The elements of the device are connected as follows. A delay line is connected to the input bus of the meter, the output of which is connected to one of the inputs of the normalizing driver 2, the other input of which is connected to the output of the adaptive driver 7, the input of which is one of the inputs of the comparator 8 is also connected to the input bus of the meter, the output of the comparator 8 is connected to one input of the coincidence element 9, the other input of which is connected to the bus reference frequency f _e, and the output to the counting input of the counter 10, which is connected to the output of code converter 11, the voltage output of which is connected to the other Rin the comparator house 8 and with the input of the voltage divider 12, the output of which is the output of the adaptive driver 7, and connected to another input of the normalizing driver 2, the direct output of the normalizing driver 2 is connected to the input of the first digital driver 13, with the S-input of the RS-flip-flop 14 and the first input of the logic element 2 AND-OR-NOT 18, and the inverse output is with one of the inputs of the match element 17, the output of the RS-trigger 14 is connected to one of the inputs of the match element 15, the other input of which is connected to the reference frequency bus f _e , and the output with counting counter 16. The direct output of counter 16 of the first digital driver 13 is connected to the input of the driver 3 start pulses, and the inverse output is connected to the R-input of the RS-trigger 14, with the other input of the matching element 17 and with the first input of the logical element 2I-OR- NOT 18, the output of which is connected to the R-inputs of the RS-flip-flop 20 and the installation input of the counter 22 of the second digital driver 19. The counting input of the counter 22 is connected to the output of the match element 21, one of the inputs of which is connected to the reference frequency bus f _e ; and the other with the output of the RS-flip-flop 20. The remaining inputs of the logic element 2I-OR-NOT 18 are connected to the output of the stop-pulse shaper 5, the input of which is connected to the output of the counter 22 of the second digital shaper 19, with the R-inputs of the counter 10 of the adaptive shaper 7, counter 16 of the first digital driver 13 and RS-trigger 4, the input S of which is connected to the output of the driver 3 start pulses, and the output to the input of the Converter 6 time-code.

A disadvantage of the known device is that it has low speed.

The purpose of the proposed technical solution is to increase performance.

This goal is achieved by the fact that in the pulse duration meter of complex shape, containing a normalizing driver and a RS-trigger and a converter connected in time, a code whose output is the output bus of the device, the first input of the normalizing driver is connected to the input bus, an inverter, a comparator, and the first matching stage are introduced , a second coincidence stage, a reversible counter, a code-voltage converter, a voltage amplifier, and a pulse shaper, the input bus being connected to the first input th comparator, a direct output of which is connected to the first input of the first stage

coincidence, the second input of which is the inverter input, the second input of the second coincidence stage and is connected to the target strobe line, and the output of the first coincidence stage is connected to the counting (summing) input of the reverse counter, the subtracting input of which is connected to the output of the second coincidence stage, the first input of which is connected with the inverted output of the comparator, and the third input is combined with the third input of the first coincidence stage and connected to the reference frequency bus, the output of the code-voltage converter is combined with the second by the comparator and connected to the input of the voltage amplifier, the output of the voltage amplifier is connected to the second input of the normalizing driver, the output of which is combined with the S-input of the RS-trigger and connected to the input of the pulse shaper, the output of which is combined with the R-input of the RS-trigger and R-input a reverse counter, the output of which is connected to the input of the code-voltage converter, the first input of the normalizing driver is connected to the first input of the comparator, the inverter output is connected to the third input of the normalizing driver. Figure 2 presents a functional diagram of a meter of pulse duration of complex shape. Figure 3 shows the timing diagrams. Figure 2 introduced the following notation:

1 - Inverter;

2 - Normalizing shaper;

3 - RS-trigger;

4 - Time-code converter;

5 - Pulse former;

6 - Comparator;

7 - The first cascade of coincidence;

8 - The second cascade of coincidence;

9 - Reversible counter;

10 - Code-voltage converter;

11 - voltage amplifier.

An irregular pulse meter, comprising a normalizing driver 2 and serially connected RS-flip-flop 3 and a time-code converter 4, the output of which is the output bus of the device, the first input of the normalizing driver 2 is connected to the input bus in order to increase the speed inverter 1, comparator 6, first coincidence cascade 7, second coincidence cascade 8, reversible counter 9, converter 10 code-voltage voltage amplifier 11 and pulse shaper 5, and the input bus with it is single with the first input of the comparator 6, the direct output of which is connected to the first input of the first coincidence stage 7, the second input of which is the input of the inverter 1, the second input of the second coincidence stage 8 and is connected to the target strobe line, and the output of the first coincidence stage 7 is connected to the counting one ( summing) the input of the reverse counter 9, the subtracting input of which is connected to the output of the second cascade of matches 8, the first input of which is connected to the inverse output of the comparator 6, and the third

the input is combined with the third input of the first coincidence stage 7 and connected to the reference frequency bus, the output of the code-voltage converter 10 is combined with the second input of the comparator 6 and connected to the input of the voltage amplifier 11, the output of the voltage amplifier 11 is connected to the second input of the normalizing driver 2, the output of which combined with the S-input of the RS-trigger 3 and connected to the input of the pulse shaper 5, the output of which is combined with the R-input of the RS-trigger 3 and the R-input of the counter 9, the output of which is connected to the input of the converter 10 code-nap tension, the first input of the normalizing driver 2 is connected to the first input of the comparator 6, the output of the inverter 1 is connected to the third input of the normalizing driver 2.

The duration meter of complex shape works as follows. The noise voltage of amplitude U _x from the input bus is fed to the first input of the normalizing driver 6 (comparator), the second input of which is supplied with the reference voltage of the _DAC from the output of the code-voltage converter 10. At the initial moment of time, the value of the noise voltage U _x from the input bus exceeds the voltage U of the _DAC coming to the second input of the comparator 6 from the output of the code-voltage converter 10, as a result of which the comparator 6 switches to a single state. The signal of the level of the logical unit from the first output of the comparator 6 is fed to the first input of the first cascade of matches 7, thereby ensuring the passage of pulses from the bus of the reference frequency to the summing input of the reversing counter 9. Reversing counter 9 during the duration of the target strobe (τ _ЦУ ) (Fig.3a ) changes its state, namely, increasing the code at the outputs until the voltage difference U of the _DAC -U _x becomes less than the quantization step of the code-voltage converter 10 (Δ _DAC ). If the voltage U _x becomes less than the U _DAC , then the comparator 6 will switch to the zero state. A single signal at the second (inverse) output of the comparator 6 allows the passage of pulses from the bus of the reference frequency through the second cascade of matches 8 to the subtracting input of the reversing counter 9. In this case, the contents of the reversing counter 9 are reduced until the voltage difference U of the _DAC -U _x less than Δ _DAC . Thus the voltage U _DAC continuously throughout the duration τ _MC monitors the magnitude of the input voltage U _x. As a result, at the end of the time τ the _CPU at the output of the code-voltage converter 10, a voltage corresponding to the average value with an accuracy not exceeding the quantization step Δ _{DAC of the} converter 10 code-voltage. The voltage from the output of the converter 10 code-voltage through the voltage amplifier 11 is supplied to the normalizing driver 2 as a threshold (reference) (figb), where the value of k is the gain of the voltage amplifier 11, determined on the basis of the probability of exceeding the random process (noise) of the threshold level of measurement, the value of which can be changed by adjusting the parameters of the amplifier. At the first input of the normalizing shaper 2, a measured pulse with a duration of τ _And (Fig.3c) is supplied, and at the second

the input at the end of the target designation strobe is fed a signal from the output of the inverter 1, as a result of which a pulse with a normalized amplitude is generated at the output of the normalizing driver 2, during which the pulse exceeds the threshold (reference) voltage level (Fig. 3d). The output pulse from the output of the normalizing driver 2 is fed to the S-input of the RS-trigger 3, under the influence of the leading edge of which the RS-trigger 3 is set to a single state, and the pulse former 5 is triggered on the trailing edge, under which the RS-trigger 3 is set to zero state. Thus, at the output of the RS-trigger 3, a voltage pulse normalized in amplitude and duration of the fronts is generated, the duration of which is equal to the duration of the measured pulse of complex shape at the level (Fig. 3d). This pulse is supplied to the time-code converter 4.

In the prototype, the measurement result is output to the output bus after a time t _И = t _ФП + τ _И , here t _tf is the time to form a threshold (reference) voltage, τ _and is the duration of the measured pulse.

In the proposed device, the output of the measurement result to the output bus occurs after a while . Consequently, the gain in speed is .

The proof of the feasibility of the proposed complex pulse-width meter is that the main input units are built on serial microcircuits: the comparator on the MC521CA2 chip, the matching stages on the 133LA4 chip, the inverter on the MC133LA chip, the reversible counter on the 133 IE7 chip, -voltage - on the microcircuit 594PA1, the normalizing driver on the microcircuit 521CA1.

Thus, the application of the proposed device can improve performance (issuing a signal to the output bus) by 2 times.

Claims (1)

An irregular pulse meter with a normalizing driver and a serially connected RS-trigger and a time-code converter whose output is the output bus of the device, the first input of the normalizing driver is connected to the input bus, characterized in that, in order to improve performance, they are introduced inverter, comparator, first coincidence cascade, second coincidence cascade, reversible counter, code-voltage converter, voltage amplifier and pulse shaper, with the input bus connected to the first input of the comparator, the direct output of which is connected to the first input of the first coincidence stage, the second input of which is the inverter input, the second input of the second coincidence stage and connected to the target strobe bus, and the output of the first coincidence stage is connected to the counting (summing) input of the reversible counter , the subtracting input of which is connected to the output of the second coincidence stage, the first input of which is connected to the inverse output of the comparator, and the third input is combined with the third input of the first stage with drops and is connected to the reference frequency bus, the output of the code-voltage converter is combined with the second input of the comparator and connected to the input of the voltage amplifier, the output of the voltage amplifier is connected to the second input of the normalizing driver, the output of which is combined with the S-input of the RS-trigger and connected to the input of the driver pulses, the output of which is combined with the R-input of the RS-trigger and the R-input of a reversible counter, the output of which is connected to the input of the code-voltage converter, the first input of the normalizing driver is connected to the first the input of the comparator, the inverter output is connected to the third input of the normalizing driver.