RU2010321C1 - Device for modelling prediction of condition and rejection of radio-electronic equipment - Google Patents

Abstract

FIELD: computer technology. SUBSTANCE: device has unit 1 for computing predicted value of average noise power, unit 2 for computing average power for predicted moment of time, unit 3 for modelling low-frequency noise which has noise generator 4, group of pulse amplitude regulators 5, the first, the second and the third lower frequency filters 6, the first and the second adders 7, pulse generator 8, starting pulse generator 9, linearization unit 10, saw-tooth voltage generator 11, two division units 12, two switches 13, two subtraction units 14, controlled voltage supply 15, root-mean square value of noise meter 16, digital-to-analog converter 17. Unit 3 has also delay line 18. EFFECT: widened operational capabilities. 3 dwg

Description

 The invention relates to computer technology and can be used as a technical training tool, as well as for the study of real blocks and elements of radio equipment by their noise characteristics.

 The purpose of the invention is the expansion of functionality by modeling the variation mode of the coefficient of evolution of the failure rate of electronic equipment (CEA).

 A functional diagram of the device is shown in FIG. 1; in FIG. 2 shows the signals at the outputs of the device blocks; in FIG. Figure 3 shows the simulation of the variation mode of the coefficient of evolution of the failure rate of the CEA element.

 The device comprises a unit 1 for calculating the predicted value of the average noise power, a unit 2 for calculating the average power at the predicted time, and a unit 3 for modeling a low-frequency noise, including a noise generator 4, a group of pulse amplitude controllers 5, a first low-pass filter 6-1, a first 7-1 and the second 7-2 adders, the second low-pass filter 6-2, an 8 pulse generator. The outputs of the regulators 5 of the pulse amplitude of the group are connected to the inputs of the first adder 7-1, the output of which is connected to the input of the second low-pass filter 6-2. The output of the latter is connected to the first input of the second adder 7-2, the second input of which is connected to the output of the first low-pass filter 6-1. The noise generator 4 is connected to the input of the first low-pass filter 6-1, the output of the second adder 7-2 is connected to the first input of the average power calculation unit 2 at a predicted time. The device also contains a trigger pulse generator 9, a linearization unit 10, a sawtooth voltage generator 11, two dividing units 12-1 and 12-2, two switches 13-1 and 13-2, two subtraction units 14-1 and 14-2, adjustable a voltage source 15, a rms noise meter 16, a digital-to-analog converter (DAC) 17. A delay line 18 is introduced into the low-frequency noise modeling unit 3. The output of the pulse generator 8 is connected to the input of the delay line 18, the group of outputs of which is connected to the inputs of the pulse amplitude controllers 5, respectively.

 The last output of the group of the delay line 18 is connected to the input of the trigger pulse shaper 9, the output of which is connected to the second input of the average power calculation unit 2 at a predicted time. The output of the sawtooth voltage generator 11 is connected to the input of the linearization unit 10, the output of which is connected to the input of the noise generator 4 of the low-frequency noise modeling unit 3. The outputs of the regulators 5 of the pulse amplitude of the group are connected respectively to the fixed contacts of the first switch 13-1, a movable contact of which is connected to the input of the third low-pass filter 6-3. The output of the latter is connected to the input of the dividend first division block 12-1, the input of the divider of which is connected to the output of the meter 16 of the rms noise value, the input of which is connected to the output of the first low-pass filter 6-1. The output of the first block 12-1 division is the first output of the device. The output of the second low-pass filter 6-2 is connected to the first fixed contact of the second switch 13-2, the second fixed contact of which is connected to the output of the second adder 7-2. The movable contact of the second switch 13-2 is connected to the input of the unit 1 for calculating the predicted average noise power, the output of which through the DAC 17 is connected to the input of the subtracted first subtraction unit 14-1. The output of block 14-1 is connected to the input of the divisible second division block 12-2, the output of which is the second output of the device. The output of the regulated voltage source 15 is connected to the input of the reduced first 14-1 and second 14-2 blocks of subtraction. The input of the subtracted second subtraction unit 14-2 is connected to the output of the average noise power calculation unit 2 at the predicted time. The output of the second subtraction unit 14-2 is connected to the input of the divider of the second division unit 12-2. The control input of the regulated voltage source 15 is the control input of the device, the control inputs of the regulators 5 of the pulse amplitude of the group are a group of control inputs of the device.

 The device operates as follows.

First, the operator establishes a given type of dependence of the average noise power, representing it in the form of a polynomial of the kth degree:
y (t) = β _o + β ₁ t + β ₂ t ² +. . . + β _k t ^k . (1)
For definiteness, we assume that k = 2. Then, dependence (1) is given by the expression
y (t) = β _o + β ₁ t + β ₂ t ² , (2) where β _o , β ₁ , β ₂ are parameters whose values are set or calculated by the operator at a given value of y (0) and the values of the coordinates of the extremum t _o , y (t _o ).

The operator, connecting the oscilloscope to the output of the first adder 7-1, using the regulators 5-1,. . . 5-P sets the calculated values in advance according to the formula (2) of the pulse amplitude at their outputs. These pulses, being summed in the first adder 7-1, form the step signal shown in FIG. 2a. This signal, after passing through the low-pass filter 6-2, is smoothed and takes on the form shown in FIG. 2b. Its values in the range from 0 to t _m are described by expression (2).

 The signal from the output of the second low-pass filter 6-2 is fed to the first fixed contact of the second switch 13-2 and simultaneously to the first input of the second adder 7-2. The second input of the adder 7-2 receives low-frequency noise from the output of the first low-pass filter 6-1, which has a given amplitude-frequency characteristic and bandwidth. As a result, a low-frequency noise model is generated at the output of the second adder 7-2 with a given change in average power, as shown in FIG. 2c, where the dotted line shows the change in average noise power. Noises of this type are characteristic of intrinsic low-frequency noise of REA elements.

 The intrinsic low-frequency noise of CEA elements is of the greatest interest from the point of view of predicting the quality of CEA, since the cause of low-frequency noise is various phenomena and defects both on the surface and in the volume of the materials of the elements. These include fluctuations in surface and space charges, changes in carrier recombination rates, current leakage, local overstresses, and rearrangement of individual sections of the structure of element materials during current flow through structural inhomogeneities, dislocations, and microcracks. Therefore, low-frequency noise with a given change in average power is the basis for creating an integrated method of non-destructive testing of CEA and its elements, in which the characteristics of low-frequency noise serve as predicted parameters of the state and reliability of CEA. As a predicted parameter of low-frequency noise, the average noise power in a given frequency band is modeled in the device.

 The noise signal at the input of the low-pass filter 6-1 comes from the output of the noise generator 4. The effective value of the noise at the output of the noise generator is set at each moment of time by the output signal of the linearization unit 10, the input of which receives a sawtooth voltage from the output of the sawtooth voltage generator 11. Moreover, the oscillation period of the generator 11 is several orders of magnitude longer than the oscillation period of the 8 pulse generator. The fulfillment of the last condition allows us to consider the noise voltage to be practically unchanged over the interval of variation of the average noise power described by expression (2). At the same time, the fulfillment of this condition makes it possible to observe a change in the ratio of the deterministic component of the amplitude of the average noise power to the rms noise value from period to period of the pulse generator 8.

 Let us consider how we evaluate the ratio of the deterministic component of the amplitude of the average noise power at a given time to the rms value of the noise.

The operator selects the deterministic component of the amplitude of the average noise power at a given time t _j , setting the movable contact of the first switch 13-1 in the jth position, where j = 1,2,. . . , P. The pulses from the output of the corresponding amplitude controller 5-j arrive through switch 13-1 to the input of the third low-pass filter 6-3. The output of the filter 6-3 receives a voltage proportional to the amplitude of the pulse at the output of the corresponding amplitude controller, which is fed to the input of the divisible first division block 12-1. At the input of the divider of the division unit 12-1, the effective noise voltage is supplied from the output of the meter 16 of the rms noise value measuring the output voltage of the first low-pass filter 6-1. Thus, at the output of the division block 12-1, the ratio of the deterministic component of the amplitude of the average noise power at a given point in time to the rms noise value is obtained.

,

, . . . ,

, . . . в моменты времени t₁, t₂, . . . , t_j, . . . .The simulated implementation of low-frequency noise with variable average power from the output of the second adder 7-2 goes to the first input of the average power calculation unit 2 at the predicted time in each clock cycle of the 8 pulse generator. In FIG. 2c shows one of such implementations and corresponding average power readings

,

,. . . ,

,. . . at times t ₁ , t ₂ ,. . . , t _j,. . . .

In block 2 of calculating the average power at a predicted time, the average noise power at a given time t _{n is} estimated for a given number of samples m.

=

(

+

+

+

)

;

= -

(

-

)-

(

-

)+

(

-

)+

(

-

); (3)

= -

(

-

)-

(

-

)+

(

-

), где Δt - интервал времени между соседними отсчетами.We give the calculation formulas for the parabola coefficients (2) with the number of samples m = 4

=

(

+

+

+

)

;

= -

(

-

) -

(

-

) +

(

-

) +

(

-

); (3)

= -

(

-

) -

(

-

) +

(

-

), where Δt is the time interval between adjacent samples.

,

,

используются в блоке 2 для вычисления средней мощности на предсказываемый момент времени t_n по формуле
y(t

)=

+

t

t $\genfrac{}{}{0ex}{}{\text{2}}{\text{n}}$ (4)
Оценка средней мощности (4) поступает на выход устройства и на вычитаемый вход второго блока 14-2 вычитания.The calculated values of the coefficients

,

,

are used in block 2 to calculate the average power at the predicted time t _n according to the formula
y (t

) =

+

t

t $\genfrac{}{}{0ex}{}{\text{2}}{\text{n}}$ (4)
The average power rating (4) is supplied to the output of the device and to the subtracted input of the second subtraction unit 14-2.

 In order to synchronize the operation of the sawtooth voltage generator of block 2 with the pulse generator 8, communication was introduced from the last tap of the delay line 18 through the former 9 to the second input of the average power calculation unit 2 at a predicted time.

The combined subtractive inputs of the subtraction units 14-1 and 14-2 receive the voltage of a predetermined threshold U _then from the output of the regulated voltage source 15. The threshold U _then is set by the operator at source 15.

 Consider the case where the second switch 13-2 is in the first position. Then the output of the low-pass filter 6-2 is connected to the input of the built-in analog-to-digital converter (ADC) of the unit 1 for calculating the predicted value of the average noise power. As block 1, a programmable microcomputer controlled by the operator is used.

,

,

при том же числе отсчетов значений средней мощности m = 4. При этом значения средней мощности не искажены действием низкочастотного шума, поскольку, как уже отмечалось, переключатель 13-2 подсоединяет к входу блока 1 выход фильтра 6-2.In block 1, according to formulas (3), the coefficients are calculated

,

,

with the same number of samples of the average power values m = 4. Moreover, the average power values are not distorted by low-frequency noise, since, as already noted, switch 13-2 connects the output of filter 6-2 to the input of unit 1.

,

,

и зафиксировав их в памяти блока 1, оператор рассчитывает предсказанное значение средней мощности по формуле (4). Полученное значение y₁(t_n) фиксируется в регистре памяти блока 1, поступая далее на ЦАП 17. Аналоговый сигнал на выходе ЦАП 17, отображающий расчетное значение средней мощности шума на предсказываемый момент времени, поступает на вычитаемый вход первого блока 14-1 вычитания.By calculating the coefficients

,

,

and fixing them in the memory of block 1, the operator calculates the predicted value of the average power according to the formula (4). The obtained value of y ₁ (t _n ) is recorded in the memory register of block 1, then fed to the DAC 17. An analog signal at the output of the DAC 17, which displays the calculated value of the average noise power at the predicted time, is fed to the subtracted input of the first subtraction block 14-1.

, (5) где y₁(t_n) - расчетное значение средней мощности шума на выходе ЦАП 17;

(t_n) - оценка средней мощности шума на предсказываемый момент времени на выходе блока 2.Thus, at the output of the second division unit 12-2, which is the second output of the device, a voltage is obtained that displays the magnitude in a given scale
K (σ) =

, (5) where y ₁ (t _n ) is the calculated value of the average noise power at the output of the DAC 17;

(t _n ) is an estimate of the average noise power at a predicted time at the output of block 2.

(t_n) зависит от величины среднеквадратичного значения шума σ на выходе фильтра 6-1.From the analysis of expression (5), it follows that for a given signal at the output of the low-pass filter 6-2 and a given threshold U _then in block 15, the numerator y ₁ (t _n ) -U _then is a constant value, and the denominator (t _n ) -U _then - a random variable, since the estimate

(t _n ) depends on the value of the rms noise value σ at the output of the filter 6-1.

 In turn, the voltage of the rms noise value at the output of the low-pass filter 6-1 is set at each time point by the output signal of the linearization unit 10, which controls the output voltage of the noise generator 4. Modeling of low-frequency noise, which varies with respect to the determinate component of the average noise power at the output of the first division block 12-1, allows us to predict the quality of CEA elements due to various kinds of phenomena and defects both on the surface and in the volume of the materials of the elements. In this case, the variation of the coefficient K (σ) or its range of values can move from the predicted positive values of uptime to the predicted values of the failure of the elements (negative values).

 These variations of the REA failure evolution coefficient can be modeled and demonstrated on a two-dimensional plane, the abscissa axis of which shows the voltage values at the first output of the device, i.e., the ratio of the deterministic component of the average noise power to the rms noise at the output of the first division block 12-1, and the corresponding values of the coefficient K (σ) are plotted along the ordinate axis.

 In FIG. Figure 3 shows the simulation of the variation mode of the evolution coefficient of the REA failures when an oscilloscope with voltage memory is supplied to input X from the output of block 12-1, and voltage Y from the output of division block 12-2 to input Y. The shift of the variation region K (σ) is shown depending on the effective value of the simulated low-frequency noise, referred to the deterministic component of the amplitude of the average noise power.

 A positive effect of this device is the demonstration in an automated mode of forecasting areas of failure-free operation of the CEA element (in Fig. 3, they correspond to areas A and B) and areas of possible failure of elements where the coefficient variations capture negative values.

 Note that in the second position of the second switch 13-2, the output of the adder 7-2 is connected to the input of the built-in ADC of the calculation unit 1 of the predicted value of the average noise power. In this case, the estimation of the predicted value of the average power at the output of block 1 will also be a random variable depending on the value of σ. Accordingly, at the output of the division block 12-2, variations of the coefficient K (σ) of two random estimates are observed. (56) Bykov M.F. et al. Diagnostics, forecasting, non-destructive testing and EA quality management. L.: SZPI, 1985, p. 64-70.

 The use of microprocessors and microcomputers in the designs and production technology of REA. Guidelines for the implementation of laboratory work. L.: SZPI, 1988, p. 43-51, fig. 8.

Claims (1)

 DEVICE FOR MODELING THE FORECAST OF THE STATE AND DISPLACEMENT OF RADIO ELECTRONIC EQUIPMENT, containing a block for calculating a predicted value of the average noise power, a block for calculating the average power for a predicted time and a low-frequency noise frequency modeling block including adders, a second low-pass filter, a pulse generator, moreover, in the low-frequency noise modeling block, the outputs of the pulse amplitude controllers of the group are connected are directed to the inputs of the first adder, the output of which is connected to the input of the second low-pass filter, the output of which is connected to the first input of the second adder, the second input of which is connected to the output of the first low-pass filter, the output of the noise generator to the input of the output of the noise filter connected to the first input of the average power calculation unit at a predicted time, characterized in that, in order to expand functionality by simulating the mode of variation of the evolution coefficient, the failure of radio-electronic equipment, it contains a third-pass low-pass filter, a trigger pulse shaper, a linearization block, a saw-shaped voltage generator, two division blocks, two switches, two subtraction blocks, an adjustable voltage source, a noise meter, a noise meter a delay line has been introduced; moreover, in the low-frequency noise modeling block, the output of the pulse generator is connected to the input of the delay line, the output group of which is connected to the input I will give the regulators the amplitudes of the group pulses, respectively, the last output of the delay line group is connected to the input of the trigger pulse shaper, the output of which is connected to the second input of the average power calculation unit at the predicted time, the output of the saw generator is connected to the noise of the low-frequency noise modeling block, the outputs of the regulators of the pulse amplitude of the group are connected respectively to the fixed contacts of the first switch a device with a movable contact connected to the input of the third low-pass filter, the output of which is connected to the input of the divisible first division block, the input of the divider of which is connected to the output of the meter of the rms noise value, the input of which is connected to the output of the first low-pass filter, the output of the first block the output of the device, the output of the second low-pass filter is connected to the first fixed contact of the second switch, the second fixed contact of which is connected to the output of the second adder, movable to the second switch cycle is connected to the input of the predicted average noise power calculation unit, the output of which is connected via the digital-to-analog converter to the input of the first subtracted subtraction unit, the output of which is connected to the input of the second divided division unit, the output of which is the output of the second the input of the reduced first and second subtraction blocks, the input of the subtracted second subtraction block is connected to the output of the average noise power calculation unit before the said moment of time, the output of the second subtraction unit is connected to the input of the divider of the second division unit, the input of the regulation of the regulated voltage source is the control input of the device, the inputs of the regulation of the regulators of the pulse amplitude of the group are the group of the control inputs of the device.

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