SU642716A1 - Device for determining mean frequency of randomly-distributed pulses - Google Patents

Description

keys to the zero input of the fourth trigger, the unit output of which is connected to the first input of the third element AND, the second input of which is the fourth input of the device, the output of the first element OR is connected to the input of setting the meter to zero, and the single output of the third trigger is connected to the first input of the fourth element And, the second input of which is connected to the output of the third delay line, the output of the fourth element I is connected to the summing input of the second reversible counter.

A significant disadvantage of the known devices is that they have a low accuracy of determining the average frequency of the pulses in the presence of interference.

The purpose of the invention is to increase the accuracy of the device.

For this purpose, in the device for determining the average frequency of randomly distributed pulses, the output of the fourth element I is connected to the input of the third delay line and to the single input of the first trigger.

The block diagram of the device shown in the drawing.

The device contains: the first element AND 1, the first trigger 2, the counter 3, the first reverse 1 counter 4, the second element AND 5, the first element OR 6, the first delay line 7, the second reversible counter 8, the third element And 9, the third delay line W, the fourth element And P, the second delay line 12, the second trigger 13, the third trigger 14, the second element OR 15, the decoder 16, the fourth trigger 17.

The operation of the device occurs in different ways, depending on the size of the interval between adjacent pulses of the sequence under investigation.

Consider the operation of the device in the following cases.

t. The time interval between the first and second pulses of the sequence under study is so small that it contains less than K scale fi lds of filling (O1Kis K corresponds to the lower limit value equal to / GGD). This case occurs when a pulse is generated from interference. In this case, the second (interfering) pulse of the measured sequence in the counter 8 does not pass due to the fact that the element II II is closed by the trigger 14. The element 11 11 will be closed until after the first pulse the counter 3 does not arrive arriving at the first input of the device. After the arrival of K pulses, the deciphertor 16 starts up and, via element I.PI 15, translates trigger 14 into a single one. condition. The first signal after this, which appears at the fourth input of the device after a delay in element 10, passes through AND 11 to

the summing input of the reversible counter 8 and through the element OR 6 to the input of the installation of the zero of the counter 3. The latter is set to the initial state and starts counting again the number of large-scale filling pulses, but already after the second signal.

Thus, with a small interval between the first row of subsequent impulses-interferences (a scale scaling pulse between each of them and the first pulses is less than / O, the device does not take into account these pulses, but takes into account the first signal that is more distant from the initial pulse TO.

Passing through the element 11 and lingering in the delay element 12 for an insignificant time, the second (regular) impulse takes the trigger 14 to the zero position and locks the input of the counter 8 to the interval in K periods fo large scale impulses of the ground.

2. The time interval between the first (previous) and second (subsequent) pulse M51 of the measured sequence is such that it fits in from the KdM of large-scale pulses (A / time interval corresponding to the upper limit value nnttar, shaft between adjacent pulses).

In this case, when the counter is filled with 3 large-scale pulses up to the number K on the code of the decoder 16, a pulse is generated which sets trigger 14 to one state, opening element 11 to pass the second (subsequent) pulse of the measured sequence to summing input of the reversing counter 8. This the pulse of the measured sequence after the delay element 10 and the element 11 is recorded in the counter 8 and sets to zero the state of the counter 3, which begins the analysis of the next interval between the pulses pulses of the measured sequence;

Thus, in the reversing counter 8, each pulse of the measured sequence will be recorded, and in the reverse counter 4, the number of 1 × 1 pulses corresponding to the sum of the durations of all the intervals between the recorded pulses will accumulate.

3. The time interval between the preceding and subsequent pulses of the investigated sequence is such that it contains more than M large-scale filling pulses (i.e., a case where the time interval is longer than the upper limit of the interval between the pulses under study).

This corresponds either to the case when the disturbance led to the disappearance of the pulse in this area of the measured sequence, or to the case when the measured sequence is already law. 64, and the measurement end signal has not yet arrived at the third input of the device. The number of mass-impulse pulses corresponding to the duration of this interval should be excluded from the measurement (removed from the reversing card 4). The impulse of the sign of such a disturbance is removed {by a binary binary counter 3 in the case when the most significant () bit of this counter goes to the single state. So the number of large-scale pulses, after which the counter 5 produces a pulse of the sign of interference, is L / 2. In this case, the previous pulse of the measured sequence is fed to the summing input of the reversing account "0 {ka 8" and is fixed in it. Simultaneously, parallel filling of large-scale pulses of counters 3 and 4 begins. At the moment when M large-scale pulses accumulate in counter 3, counter 3 at the output produces an impulse sign of interference, which passes through the open element 5 to the zero input of trigger 2 and sets it to zero state. Element AND 1 is closed, and the flow of large-scale pulses from the first input of the device to the summing inputs of counters 3 and 4 is stopped. In addition, the impulse of the disturbance feature sets to zero consisting of counter 3 and is fed to the subtracting input of the reversible counter 8, subtracted from the written number in it there is one. The same impulse of the disturbance feature after delays in the delay element 7 for the duration of the transients in the triggers of the counter 4 goes to the subtracting input of the reversible counter 4 and reduces the current in it by the value of L /. Before the next pulse of the measured sequence arrives, all the counters of the device will be in the disconnected state, since elements 1 and 11 are closed.

Thus, the essh time interval between pulses of the measured sequence is greater than M Gy. then the number in the reversible counter 8 does not increase (first, the unit is added, and then the sign of the disturbance is subtracted). In the reversible counter 4, the scale pulses for this period also do not accumulate, since the M scale pulses counted in it before the appearance of the sign of the disturbance sign are then subtracted. Therefore, the resulting interference is excluded from consideration.

4. The time interval between the previous and the subsequent pulses of the measured sequence exactly corresponds to the M scale pulses (i.e. exactly corresponds to the upper limit value of the interval between the pulses under study).

In this case, uncertainty may arise, when the normal interval between the correspondents is And after the end signal of the measurement, and the large-scale filling pulses continue to flow to counters 3 and 4, Only after this, And5 The 1 mpulse interference jam, which closes the AND element and performs the information removed from the counters 4 and 8, respectively, about M 1 mpuls and about the final pulse of the measured sequence.

In this case, the number of intervals between pulses of the measured sequence without interference is recorded in the reverse} counter 8, and the number of scale pulses corresponding to the sum of the intervals of the measured sequence in the counter 8 {ke 4).

Frequency generator scale and pulses

Claims (2)

The initial accuracy of the measured scientific research institute is taken, or from the known upper boundary value between the input pulses. It cannot be distinguished by the gray pulses of the measured sequence from the interval resulting from the interference. In this case, the impulse of the sign of interference from counter 3 through the element 5 could arrive at the zero input of trigger 2 simultaneously with the posting on the unit a1 input of the same trigger of the measured sequence from the output of element 11. But this does not occur because 5 is closed by trigger 13, to the zero input of which an unused pulse of the measured sequence arrives. Therefore, the pulse of the sign of interference from the output of counter 3 does not drive through element 5 to the zero input of trigger 2. After the passage of delay element 12, the pulse of the measured sequence will set trigger 13 again to unity state, but counter 3 will already be in zero state P1I thanks the effect of the non-delay of the pulse of the pulse from the output of the element of AND P. The considered cases fully characterize the operation of the device in all its modes. At the time of the measurement o1, the signal of the end of the measurement arrives at the device’s heated input, which sets the trigger 17 to the zero state. As a result, the And 9 element is closed, stopping the access of the pulses of the measured sequence. If the interval between the last pulses and the signal of the measurement is shorter than the MG, then (as described in cnyiiae 3) this interval will be considered an interference and will be withdrawn from consideration even before the signal of the end of measurements. If the interval between the last pulse of the measured continuity and the network end of measurements is less than MCO, then the And 1 element continues to remain. Thus, the proposed device allows to increase the accuracy of determining the frequency of randomly distributed pulses in the presence of interference. Formula of the Invention A device for determining the average frequency of randomly distributed pulses, containing the first AND element, the first input of which is the first input of the device, the second input connected to the single output of the first trigger, and the output of the first AND element connected to the summing input of the first reversible counter and the counting input of the counter, the first output of which is connected to the input of the decoder, and the second output is connected to the first input of the second element I, the output of which is connected to the zero input of the first trigger, with ne By the first input of the first element OR, with the output input of the second reversible counter n with the input of the first LIRSHI zadfzhkn, whose input is connected to the subtractive input of the first reversible counter, the second input of the second element I is connected to the single output of the second trigger, zero, and a single outlet and a single outlet, and a single connection of a single outlet, and a single connection of the second circuit AND, to the second output of the second trigger; delay and connected to the output of the third element And the ed-out input is combined with the zero input of the third trigger and connected to the output of the second delay line, the OUTPUT of the decoder is connected to the first input of the second element Ta I, the second input of which is combined with the installation input of the first and second reversible meters to zero, with the single input of the fourth trigger and is connected to the second input of the device, the third input of which is connected to the zero input of the fourth trigger, the single output of which is connected to the first input of the third element And, the second input of which is the fourth input of the device, the output of the first element OR is allocated to the set zero meter, and the single output of the third trigger is connected to the first input of the fourth element The second input of which is connected to the third delay line, the output of the fourth element I is connected to the summing input of the second reversible counter, characterized in that, in order to increase the point, the output of the fourth element I is connected to the input of the third delay line n to the first input of the first trigger . Sources of information taken into account at the first examination. 1. USSR author's certificate No. 328396, cl. G 01 R 23/10. 1971. 2. USSR author's certificate No. 311281 of a club. 07/07/52, 1970.