SU1018019A1 - Method of stroboscopic conversion of periodic electrical signals - Google Patents

Abstract

A METHOD OF STROBOSCOPIC TRANSFORMATION OF PERIBDIC ELECTRICAL CAMS OF PICTURE SIGNALS / consisting of asynchronous with the input signal the pulse conversion of this signal, at which the discrete values of the signal are read at the moments of gating (sampling), are formed at the times of gating (sampling), are formed at the same time as the sampling (sampling), are formed by the sampled signal at the time of gating (samples), they are formed using the same pattern at the time of gating (samples), and they are formed using the same pattern at the time of gating (samples), they are formed using the same pattern at the same time as the gating (samples), they are formed by using the same software at the time of gating (samples), they are formed using the same pattern at the same time as gating (sampling}; each sample number i in the order of arrival,, 2, ..., replace the number -) of each sample taken with the calculated number and reproduce the transformed signal according to Rams in the order of natural increase of numbers A, i.e. over a 1, 2, ..., and a / a, so that, in order to reduce the time for receiving the converted signal, the process of storing the samples from the first and second to the next two subgroups of samples belonging to one front of the first extended signal , determine the integer number Z of the periods of the strobe sequence in one extended signal, determine the proportion U. | p, in which 0 is the amplitude U of the third sample, belonging to the same C as the first C extended signal, the front of the second extended signal and entered into the interval between u slabs (J and IJ, the first and second samples, divides this interval, and calculate the numbers А i equal to.-ip (mod Cpz., where mod is the operation take modulo — LY. for the first and X) of the second sample the leading edge of the extended signal, & A: and the process of storing the samples ends on the sample with the number i pZ-fX Ф

Description

The invention relates to electrical measuring instruments and can be: used for the study of nepijtodic electrical signals cb for an unknown period in: automatic digital measuring systems.,;

A known method of stroboscopic oscillography, based on random coincidence of strobe pulses with a repetitive test signal, in which the next | the registration of the match was carried out only when the strobe pulse | ca coincides with the next interval to be investigated. my signal, which is separated from the previous one at a given time interval;

Cl. . ;.

The disadvantage of this method is that: a large time of the stroboscopic conversion is due to the fact that the samples of instantaneous values are not carried out for every page pulse. . .i

The closest to the 13b; the technical essence is:; the method of stroboscopic conversion, which consists in asynchronous, but with the input signal pulsed: the transformation of this signal, at which the discrete values are read at no time of gating | sampling, form a sampled sequence of paired signals, form a reference sequence of short pulses with a frequency equal to the frequency of the expanded signals, form a transformation interval, the edges of which are used for the coincidence pulses of strobe pulses with pulses of the reference-: sequence, remember in the conversion interval all the samples with the assignment of the number | a 1 in the order of arrival, il, 2, j .. | Ng is the number of samples and; NV is the number of extended signals in: the conversion interval; each sample is assigned to g by the number i and the number is Ai, calculated by the formulas {i e AV iNh (TOBYV), where -) 1,2, ... j, HB moflu, reproduced the transformed signal from samples taken in the interval of the transformation, in the order of the natural increase of numbers

ks ,, Ai 1,2, ... NbCZZ. i.

The disadvantage of this method | is a long lead time | the converted signal - the time interval; the moment of the beginning of the trans | before the moment of termination i of the reproduction of the transformed | signal. This is due to the fact that | sequence of operations method | a

is carried out in time in four main successive stages: phase 1 of waiting for the initial limit of the transformation interval, c. the quality of which is the first coincidence pulse of a strobe pulse with a short pulse of the reference sequence; the stage 2 of storing the samples in the conversion interval; the stage 3 of determining the Ai 1 stage 4 of reproducing the transformed signal. Since the start of the conversion is independent with respect to the period of the input signal, the duration of stage 1 can vary from 0 to the value of Ny, T, where Tu, 1 / Pu} Pn is the follow frequency of the expanded signals, and on average is NnT, / 2, i.e. half the duration of step 2 (conversion interval). The long duration of stage 1, as well as the impossibility of parallel stages 2 and 3, 4, increases the time

receiving a transformed signal.

i

The purpose of the invention is to reduce the time to receive the converted signal ..,

The goal is achieved by the fact that according to the stroboscopic conversion method, periodic electric signals, consisting in asynchronous with the input signal, pulse conversions of this signal, at which discrete values of the signal are read at the moments of gating (samples, form a sequence of enhanced signals, take samples from assigning each number 1 in the order of arrival, 1 1,2, ..., 3, replacing the number i of each taken sample with the calculated number A and reproduces The signal from the samples in the order of the natural increase of the numbers A, -, i.e. according to A. - 1,2, ..., begin to memorize the samples from the first and second - the next two additional samples belonging to one the edge of the first extended signal, determine the integer number Z of the gating sequence periods in one extended signal, determine the proportion X | p in which the amplitude of the ultrasound of the third sample, belonging to the same as the first extended signal, the front of the second extended signal and the incoming signal the interval between the amplitudes of U and Ui p The first and second samples, divides this interval, and calculate the numbers Ai, equal to Ai 1P (App Cr + XII, where the operation is modulo, and

X Ui-U-i 1

5 - yy-nl first and second lig Ua.

borks belonging to the leading edge of the extended signal, and the process of storing the samples ends at. sample number i pz + х. The method is implemented as follows. First and second samples are selected: two samples of the sample at the front or rear front of the first, after the start of the stroboscopic transformation, the extended signal. At the same time, all samples are memorized, starting with the first one, taken separately from the strobe pulses, asynchronous with the signal under study. From the following after the first and second samples, the third sample is selected. The third sample is determined from the condition that it is taken on the same front of the second extended signal on which the first and second samples were taken in the first expanded signal, and that its ultrasonic amplitude falls within the interval between the amplitudes U and the first and second samples. The integer Z is determined from the period of the strobe sequence in the interval between the second and third selections, i.e. The number of samples in one extended signal, for example, is calculated by counting the number of strobe pulses in the interval of the second and third samples, including one of them (the second or the third). Determine the proportion L / p in which the amplitude of the third sample divides the interval between the amplitudes of the first and second samples. The proportion determined by the formula, for example, for samples taken at the leading edge. X Oi-Me R Og-O /. J-y. -. l Know the values of Z, X and p, determine the number of samples NI / -which need to be remembered, equal to: V Знг1 values, р and NV, make the arrangement of samples / i.e. for samples that are naturally numbered in the order of their receipt, the initial collection is assigned number 1, follow number 2, etc., - “- that - number 4, A 1,2, ..., N-,) assign numbers; A-, 1p (), (.b), where ririod is the operation of the module: If, after the arrangement, reproduction: lead the converted signal across the samples in the order of the natural increase of nsDver,. from the sampling A 1 to the sampling A A pz -I-X t, then a converted signal is received, displaying the form of the signal under study. The diagram shows the structural electrical circuit of the device, actually the proposed method. The device consists of stroboscoic mixer 1, amplifier expander 2, analog-to-digital converter (ADC 3, generator 4. Strobe pulses, first block 5 of code comparison, shift register b, first counter 7 pulses, alchea slit 8, second counter 9 pulses, The second block compares the codes, the first and second memory blocks 11, 12. The device operates as follows: In the initial state, the shift register 6, counters 7 and 9, the hardware of the calculator 8, blocks 11 and 12. memory are set to O. The operation of the ADC 3 ,,. Counters 7 and 9. is prohibited. Shift and The {{information in shift register 6 is resolved, but since these operations are performed after a new sampling code from ADC 3 arrives, they are not implemented. The strobe-impliol from generator 4 is fed to the second input of strobe-pulse 1, to the first input of which the researched signal. At the output of amplifier-distributor 2, there is an amplified expanded signal. 3 The initial time a start signal is applied to the first control input of the A / D converter 3 and enables its operation. In this case, the digital codes of the samples are received in turn at the inputs of the deregistration of the second register b, which records at the trailing edge, and shifts at the leading edge of the received code pulses. Block 5 of code comparison in the case of p, the codes of two successively taken samples U and Ujt are not equal to each other, i.e. in the case when they lie on the front of the widened signal, a signal is selected, according to which: the first sample is copied to the memory cell with the number l I of the second memory block 12 (code U); the second sample (code Uj.) is copied to the memory location with the number i .2 of the second memory unit 12; the entry into the spacing cells of the second memory block 12 is broken) counters 7 and 9 are working | the counter 9 is set to the state in the calculator 8 readings KOjpM Uts and U, j,} the control input of the calculator 8 is blocked (. After this, blocks 1-6 continue to work as written. The calculator 8 calculates the diffraction of the DL) it ruins its sign, counters 7 and 9 count the number of entries to their gate inputs. In addition, after the arrival of the code of each subsequent sample of the first information inputs, the calculator 8 checks whether its amplitude falls into the interval between the amplitudes of the first and second samples. In the case where the specified interval is sampled, the calculator 8 reads from the shift register 6 codes and Ua f calculates the difference dO Uj - Uf and compares the signs of di and li. If the signs do and are different, i.e. Since the sample Ujj is not taken on the same front as the first and second samples, the process of recording samples into the second memory block 12 and strobe pulses with counters 7 and 9 continues. If the signs of CiU and whether are the same, i.e. sampling with am. by taking a second and second samples on the same front as the first and second samples, the calculator 8 remembers U as - UZ / reads the number Z recorded in it from the first counter 7 and the received data Z, Uj. , From, and U calculates according to the formula (I) the value in the form, for example, of an irreducible fraction, calculates according to the form le (2) the value N and according to the formula (3) 1 number А. The value (pz. +%) From the information outputs of the calculator 8 is fed to the first inputs of block 10 of code comparison. At the moment when strobe pulses are counted in the second counter 9, block 10 generates a signal that prohibits the operation of the ADC 3 and memory 2 Samples are ordered. At the same time, as the calculation of the noro. In A | and receiving samples, the calculation of 8 Produces the sampling, i.e. the addresses (numbers) (at which the samples were recorded in the second memory block 12 in the order of memory), sets the address (number) A, calculated according to the formula (3), Address Ai goes to the address inputs of the first memory block 11, and A cell from the cell with the address l of the second memory block 12 is copied into the cell with the address A-, of the latter. After the census of the sample number (pZ- + X), from block 12. memory to memory block 11, the cycle the strobe conversion is terminated. The converted signal, read from the first memory block 11 by the samples in the order, is The increase in addresses A-, displays the form of the signal under investigation. The operations of the proposed method are carried out in four main phases: phase 1, waiting for the initial boundary, the conversion interval, which is used for the first of two samples that lie on the front of the extended signal} phase 2 Memorization (pZ + X) - samples {conversion interval)} step .3 of calculating A 1g after which step 4 of reproducing the converted signal can be performed. The duration of stage 1 in the implementation of the proposed method of stroboscopic conversion cannot exceed the values of T — the period of the follow-up of extended signals — and on average is Ti / 2. In addition, the sequence of operations of the proposed method allows to start step 3. before the end of step 2, since the values of Z, U, Ua and U-, necessary for carrying out step 3, are obtained during the time Tu | from the beginning of stage 2, including in general a few extended signals (). Reducing the duration of stage 1 from the start of the conversion to the beginning of the conversion interval, as well as the possibility of performing steps 2 and 3.4 in parallel, reduce the time to receive the converted signal.

Claims (1)

METHOD FOR STROBOSCOPIC CONVERSION OF PERIBIDIC ELECTRICAL SIGNALS / consisting in. pulsed conversion of this signal asynchronous with the input signal, in which the discrete values of the signal are read at the moments of gating (sampling), a sequence of extended signals is formed from consecutive samples, the samples are stored with each number assigned to it in the order of arrival, i = l, 2, ..., replace the number -I of each sample taken with the calculated number A ^ · and reproduce the converted signal from the samples in the order of natural increase of numbers A ;, i.e. by A; = 1, 2, ..., on the basis of the fact that, in order to reduce the time of receiving the converted signal, the process of storing samples from the first and second or two consecutive samples belonging to one edge of the first extended signal, define an integer! periods of the gating sequence in one extended signal, determine the proportion 7 | p, in which the amplitude 1C of the third sample, at. corresponding to the same as that of the first extended signal, the edge of the second extended signal and falling between the amplitudes (J * and <0 ^ of the first and second samples, divides this interval, and numbers A; equal to A; - tp ( mod Cpz + xl), where mod is the operation to take modulo -4- = m *. for the first and r are the second samples belonging to the leading edge of the extended signal, and the process of storing samples is completed on the sample with the number i = pX + X SU .... 1018019