SU1325530A2 - Device for determining distribution of probabilities of random process parameters - Google Patents

Abstract

The invention relates to specialized computer aids for measuring the statistical characteristics of random processes, and is in addition to the author. St. No. 968826. The purpose of the invention is to improve accuracy. For this purpose, the device contains an additional threshold element 19, a clock pulse generator 18, a key 17, a counter 16, and an additional one-oscillator 15. This makes it possible to further increase the selectivity of the device when measuring the probability distributions of amplitudes of electromagnetic signals generated by ground lightning. These signals, in an unguarded form, contain information on the distribution of electric charges and their spatial and temporal variation during the development of lightning discharges. In this connection, the distributions of their amplitudes reflect the corresponding distributions of lightning currents, C, 1, the proposed device makes it possible to obtain also the probability distributions of the amplitudes of lightning currents, which are necessary for calculating lightning resistance. 1 sludge. about (l sob ate sl

Description

The invention relates to specialized computational tools for measuring the statistical characteristics of random processes, can be used in the study of disturbances of the Earth's electromagnetic field caused by lightning discharges, and is an improvement to the invention in the author. St. No. 968826.

The purpose of the invention is to improve accuracy.

The drawing shows a block diagram of the proposed device.

A device for determining the probability distributions of the parameters of a random process contains a signal sensor 1 connected in series, a single vibrator 2, an AND 3 element, a pulse shaper 4, a pulse amplitude modulator 5, and a multichannel amplitude analyzer 6, as well as a series-connected filter 7, a peak detector 8, the subtraction unit 9 and the threshold element 10, the filter 11 and the peak detector 12 are connected in series; in addition, the device contains a single vibrator 13, a peak detector 14, an additional single vibrator 15, snip 16, the key 17, a generator 18, a clock 19 and an additional monostable multivibrator.

Filter 11 is tuned to the maximum spectral density of electromagnetic signals generated by ground lightning, and filter 7 to the maximum spectral density of signals generated by cloud lightning. The signal at the output of counter 16 appears only if the number of pulses at its counting input exceeds a predetermined value corresponding to the pulse duration at the control key input, equal to 100 µs.

The device relates lightning to ground-based and registers the corresponding signal while simultaneously fulfilling three conditions: the signal value at the output of the filter 11 exceeds the preselected threshold level; the magnitude of the signal at the output of the filter 11 is larger than the magnitude of the signal at the output of the filter 7 by a preselected value; the pulse duration at the output of the additional threshold element 19 exceeds 100 ISS.

In some cases, when measuring the probability distribution of the parameters of a random process, for example, the amplitude of electromagnetic signals generated by lightning, signals generated by lightning of the wrong type, but large in amplitude, are recorded. When ground lightning is registered, close cloud lightning can be partially recorded. Therefore, the task is to exclude the registration of signals with a duration of less than 100 ISS.

The device works as follows.

The analyzed signal from the output of the sensor 1 signal is supplied simultaneously to

the input filters 7 and 11, the one-shot 2, the peak detector 14 and the threshold device 19. When the signal exceeds the single-shot threshold

2 a rectangular pulse appears at the output of the latter, the duration of which is equal to the maximum duration of the signals under study and can be set to 1.5 s. Frontline of this

Pulse peak detectors 8, 12, and 14 are brought to a working state (in the initial state, the peak detectors are clamped).

If the magnitude of the signal at the output of the filter 11, which is tuned to the maximum spectral density of electromagnetic signals generated by ground-based fields, exceeds the response threshold of the single-oscillator 13, the latter gives an enabling pulse to one of the control inputs of the element 3. The duration of this pulse

0 can be chosen equal to the pulse duration at the output of the one-shot 2. The signals from the outputs of the filters 7 and 11 are fed to the inputs of the peak detectors 8 and 12, respectively, by means of which the highest amplitudes of these signals are remembered until the end time of the signals . The signals from the outputs of the peak detectors 8 and 12 are fed to the corresponding inputs of the subtracting unit 9. The difference signal from the last output is fed to the input of the threshold element 10, which can be used as a Schmitt trigger. If the magnitude of the signal, the output of the peak detector 12 is greater than the magnitude of the signal at the output of the peak detector 8 by an amount greater than the threshold of triggering of the threshold element 10, the latter gives a permit pulse to the second control input of element 3. When the signal from the output of sensor 1 signals exceeds threshold level, also triggered device 19 is triggered, for which the Schmitt trigger can be used. At its output, a rectangular pulse appears, the duration of which is equal to the duration of the signal

5 at the output of the sensor I signals. This pulse arrives at the control input of the key 17 and the zeroing input of the counter 16. The clock pulse generator 18 generates a sequence of short pulses with a predetermined following period, for example

0 5 ISS. For a time equal to the pulse duration at the output of the threshold element 19, these pulses pass through the public key 17 and are counted by the counter 16. When their number exceeds a predetermined value (for example, 20 when the period

5 of the following 5 µs), at the output of the counter 16, a rectangular pulse appears, the leading edge of which is the one-shot 15, which gives an enabling pulse to the third control input of the And 3 element.

In this case, the back of the pulse from the output of the vibration damper 2 starts the pulse shaper 4, which produces a normalizing pulse to the control input of the pulse amplitude modulator 5. In this case, the information input of the modulator 5 is supplied with a quasi-constant voltage from the output of the peak detector 14 whose value is equal to the maximum amplitude of the signal at the input of the peak detector 14. Thus, at the output of the modulator 5, a pulse with normalized parameters appears, whose amplitude hydrochloric amplitude of the signal. Depending on its amplitude, this pulse is recorded in the corresponding channel of the amplitude analyzer 6. After the one-shot 2 returns to its original state (the pulse at its output ends), the voltage at the output of the peak detector 14 begins to decrease and when it reaches a certain level peak detectors 8, 12, and 14 are reset. The falling edge of the pulses from the outputs of the threshold element 19 and the driver of the 4 pulses returns to the initial state the counter 16 and the additional one-shot 15, respectively.

The device does not register electromagnetic signals if at least one of the following situations takes place: the signal size at the output of the filter 11 does not exceed the threshold level chosen in advance; the magnitude of the signal at the output of the filter 11 does not exceed the magnitude of the signal at the output

filter 7 at a pre-selected value; the pulse duration at the output of the additional threshold element is less than 100 µs. In all cases, the pulse former 4 is not triggered and, therefore, the signal generated by such a lightning is not recorded by the analyzer 6.

When examining electromagnetic signals generated by ground lightning, the passband of filter 11 can be (chosen 5-10 kHz, and the filter 7 - 25-50 kHz.

Claims (1)

Invention Formula 15 A device for determining the probability distributions of the parameters of a random process according to ed. St. No. 968826, characterized in that, in order to improve accuracy, it contains an additional one-shot, counter, clock generator, a key, and an additional threshold element, the input of which is connected to the output of the signal sensor, and the output is connected to the reset input of the counter and control key input, the information input of which is connected to the output of the clock pulse generator, and the output of the key is connected to the counter input of the counter, the overflow output of which is connected to the information input of the additional one-vibrator, the input Novki initial state which soedi30 nen with an additional output of the pulse shaper, and an additional monostable output is connected to the auxiliary input element I. 20