SU1237997A1 - Device for measuring depth factor of amplitude modulation - Google Patents

Abstract

The invention relates to a measurement technique and can be used to measure the depth of amplitude modulation and the coefficient of amplitude modulation of measured signals extracted by means of a mobile electric power installation. The purpose of the invention is to increase the speed and accuracy of measurements - to achieve (L

Description

by reducing the digital processing time and converting the measured signal. For this purpose, a null organ 5, a pulse shaper 6, a delay element 11 and an OR 12 element are introduced into the device. In addition, the device contains a terminal 1 for connecting a source of the measured signal, an input unit 2, an analog-to-digital converter 3, a pulse generator 4, h is a dongle key 7, register

The invention relates to a measurement technique and can be used to measure the depth of amplitude modulation and its coefficient of amplitude modulation of measured signals produced by means of a mobile electric power plant.

The purpose of the invention is to increase the speed and accuracy of measurements by reducing the time of digital processing and conversion of the measured signal.

FIG. 1 shows page 5 of the device cturner circuit; 2 and 3 are examples of the implementation of the control unit and the minimum and / or maximum amplitude power units, respectively. The device contains a terminal 1 of the device for connecting the source of the measured signal, the input unit 2, the analog-digital converter 3, to the trigger input of which is connected pulse generator 4, zero-organ 5, pulse shaper 6, h-bit key 7, register 8, control unit, comparison unit 10, delay element 11 whose input is connected to the first input of the OR element 12, selection blocks minimum 13 and max 14 mal amplitudes. The computing unit 15, which includes the division unit 16, the difference unit 17 and the adder 18, the indicator 19 and the output terminals 20 of the device for connecting the indicator {the depth of amplitude modulation of the measured signal.

The control unit 9 is made in the form of a first delay line 21, a second P-paired single key 22, a second delay line 23, and a second register 24.

8, the control unit 9, the comparison unit 10, the allocation units of the minimum 13 and maximum 14 amplitudes, the computing unit 15, which includes the division unit 16, the difference unit 17 and the adder 18, the indicator 19 and the output terminals 20 of the device. Examples of the implementation of block 9 and blocks 13 and 14 are shown on. drawings in the specification. 3 3.p, f-ly, 3 ill.

five

0 5 o

five

Blocks in the division of the minimum 13 or / and maximum 14 amplitudes of the ripped signal are made in the form of a third AND-bit key 25, a reference element 26, a third delay line 27 and a third register 28.

The device works as follows.

The measured signal through terminal 1 and further through the input unit 2 is fed to the inputs of the zero-body 5 and analog-digital converter 3, which is triggered by a signal of a constant frequency from the output of the generator 4 pulses. Null-organ 5 converts the measured signal into pulses, the beginning and end of which are determined by the transition of the measured signal through zero. The shaper 6 of the pulse fronts generates the sync pulses arriving at the command input of the control unit 9. A / D converter 3 converts the amplitude of the measured signal into a binary parallel code. In the initial state, register 8 is in the zero state. Comparison unit 10 operates in such a way that, at its output, an AB signal appears only when the code supplied to its first input is greater than the code supplied to its second input. By this signal, the code of the analog-to-digital converter 3 is rewritten via the ti-bit key 7 to the register 8.

Suppose that the start of operation of the device coincided with the beginning of the positive half-wave of the measured signal. In this case, the signal A B is generated until the measured signal reaches the maximum amplitude in dan3

the period of the measured signal. With each occurrence of the A 5 V signal, the register 8 is zeroed out and the analog-digital programmer 3 code corresponding to the comparison moment is copied into it. After passing the maximum of the positive half-wave, the formation of the signal A B is stopped. Thus, at the time the clock 6 is generated by the shaper 6, the register 8 contains the code of the maximum value of the measured signal in the positive half-wave of the first period. The synchro pulser control unit 9 writes the code of the first envelope point of the measured signal to its register 24 using the –discharge key 2, and through the delay lines 21 and 23 and the OR element 12 resets the register 8. In the initial state, the register 28 in the selection blocks the minimum 13 and maximum 14 amplitudes are in the single (zero) state. Comparison element 26 in block 14 of the maximum amplitude laziness operates similarly to block 10 of comparison. In block 13 of the minimum amplitude, comparison element 26 generates a signal. Thus, in the first half-wave, element 26 in blocks 13 and 14 of the comparison performs a census into registers 28 of the code entered in register 24. At the end of the next half-wave of the measured signal in register 8, the code of the maximum amplitude of this half-wave is recorded. For the next sync pulse from the output of driver 6, this code is rewritten into register 24. Then register 8 is zeroed. Depending on the VC signals of the comparison element 26, the code from the register 24 is copied to the register 28 of the minimum 13 or / and maximum 14 amplitude blocks. If the codes in register 24 are equal in the successive half-waves of the measured signal, no change in the state of registers 28 occurs. Thus, at the end of the specified measurement time in the register 28 of the minimum amplitude extraction unit 13, a code corresponding to the minimum amplitudes of the measured signal in a given time interval is recorded, and in the register 29 of the maximum amplitude selection unit 14, the code corresponding to the maximum amplitude of the measured signal. Amount

to

f5

20

25 5

2379974

 during the whole measurement time, the registers of the registers 28 of blocks 13 and 14 of the minimum and maximum amplitudes, i.e. by the end of the specified time, at its output there is a code proportional to the sum of the maximum and minimum amplitudes of the envelope of the measured amplitude-modulated signal. The output of the difference block 17 is a code, pass through: the ionic difference of the maximum and minimum amplitudes of the envelope of the measured signal, which is proportional to the depth of the instant modulation of the measured signal. Through the terminals 20 of the device, it can be fed to an indicator measuring the depth of the amplitude modulus hgt, hiTo A (i d, „with it„ „, where imrx min is the maximum and minimum amplitude of the measured signal. At the output of the dividing unit 16, at the end of the measurement time, the calculating unit 15 generates a signal proportional to the coefficient m h amplitude modulation bluins determined by a mathematical expression of the form

m

max mic

with.. .,,,.- .

moks ming

25 5

five

0

five

0

The measurement results are recorded by indicator 18.

Claims (4)

Invention Formula 1, A device for measuring the depth ratio of an amplitude modulation comprising an input unit, the input of which is connected to the terminal of the device for connecting the source of the measured signal, and the output connected to the information input of the analog-digital converter, the outputs of the latter through the and -discharge key are connected to the corresponding the inputs of the register, the outputs of which bits are connected to the corresponding first inputs of the comparison unit, the outputs of the blocks of the minimum and maximum amplitudes are connected to the corresponding input am computing unit, the output connected to the input of the indicator, and a pulse generator, characterized in that, in order to increase the speed and accuracy of measurements, a null organ, a pulse shaper, delay elements and OR are introduced into it, the analog-to-digital converter input is connected via a serially connected zero-org and pulse shaper connected to the command input of the control unit, the information outputs of which are connected to the corresponding inputs of the minimum and maximum amplitude selection modules, and the information inputs with the corresponding outputs of the register bits the second information inputs of the comparison unit connected to the corresponding information outputs of the analog-digital converter, the output of the comparison unit through the delay element It is connected to the control input of the I-bit key and through the OR element to the triggering input of the register, the second input of the OR element is connected to the command output of the control unit, the trigger input of the analog-digital converter is connected to the output of the pulse generator. 2. The device according to claim 1, that the control unit is made in the form of two delay lines, the second n-bit key and the second register, while the input of the first delay line is connected to the code the second delay line and the control input of the second and -disable key, the information outputs of which are connected to the corresponding inputs of the second register. 3. The device according to claim 1, is cast It seems that the block is The minimum or maximum amplitudes are made as a third M-bit key, a third delay line, a comparison element and a third register, while the information inputs of the third n-bit key are connected to the corresponding first inputs of the comparison element, the second information inputs of which are connected to the corresponding 1 dim information outputs of the third register, the information inputs of which are connected to the corresponding information outputs of the third h-bit key, the control input of the last A third delay line is connected to the output of the reference | I element with the trigger input of the third register. 4. The device according to claim 1, characterized in that the computing unit is made in the form of a difference unit, a division unit and an adder, with the first and second information inputs of the adder being connected to the corresponding first and second informa- tion inputs of the difference unit , the information outputs of the adder and the difference block are connected to the corresponding first and second information inputs of the division unit, the output of the difference block is the output of the device for connecting the indicator of the amplitude modulation depth of the measured signal. On the element ,, ff / ftl From register 8 11-X 22 ( /four rm From form 4iro8o / gge / 7 d // cf S / rof iJ S and / 4ОЗаг. Г ffm лона 3 25 F Ff / Va 5 / JOH 15 Editor N.Gorvat Compiled by L. Muranov Tehred L.Oleynik Proofreader A. Obruchar Order 3285/46 Circulation 728 Subscription VNIIPI USSR State Committee for inventions and discoveries 113035, Moscow, Zh-35, Raushsk nab., d, 4/5 Production and printing company, Uzhgorod, Projecto st., 4 {I " 27 26 1 t Fig 5