SU752170A1 - Digital meter of signal effective value - Google Patents

Description

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The invention relates to a measurement technique, in particular to digital devices for measuring the actual value of deterministic and random signals, and can be used in communication technology, in the production and testing of various radioelectronic devices and systems, as well as in scientific research.

A digital correlometer is used, which is used as a meter of a valid signal and operates in the mode of measuring the autocorrelation function of a signal at zero time delay, followed by extracting the square root of the result, containing an input amplifier, a pseudo-random number generator with a switch, two digital-to-analog converters, two comparators, a generator clock pulses, multiplier, integrator, reading circuit and register. i device i.

However, such a meter has a two-channel structure, contains many analog nodes, is relatively unstable, has a large error of measurement results and a low speed.

Also known is a correlometric digital meter of the effective value of the signal, which contains an input device, the output of which is connected to the first inputs of the comparators, a clock generator, the first output of which is connected to the digital analogue converter through the first pseudo-random number generator and to the first information input of the arithmetic device connected in series with recording device

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The disadvantage of this meter is a relatively large measurement time, which is limited by the comparators gating frequency and the 3-time setting of the digital-to-analog converter. The purpose of the invention is to increase the fast action of the digital meter of the actual value. This goal is achieved by the fact that a digital meter of a current signal value containing an input device whose output is connected to the first inputs of 2 I comparators, a clock generator, the first output of which is connected to a digital-analog converter and the first information input of an arithmetic device through the first pseudorandom number generator Two current sources are connected in series with the registering device, two dividers from P -1 in series connected resistors in each oh, two switches, a second pseudo-random number generator and an OR element, the output of the first current source and the direct output of the digital-to-analog converter, as well as the output of the second current source and the inverse output of the digital-analog converter, are connected to the corresponding pins of the first and second dividers, one of the terminals of each the resistors of both dividers are connected to the second input of the corresponding comparator, the gates of the comparators are connected to the second output of the clock generator connected to the pseudo-random number generator, whose output is connected to the second information input of the arithmetic unit and to the control inputs of both switches, whose information inputs are connected to the comparators, the first output of the first switch and the inverse output of the second are respectively connected to the inputs of the OR element, the output of which is connected to the control The input of an arithmetic unit allows you to increase the frequency of the comparators, without increasing the switching frequency of the digital-analog converter. azovatel and thus juice ratit measuring time. The degree of increase in speed depends on the number of parallel-running comparators, as well as on their speed. The measurement error in the proposed meter remains the same as in the known device. 04 The drawing shows a block diagram of the proposed digital meter of the effective value of the signal. The meter contains a current source 1, the output of which through a divider from (n-l) series-connected resistors 2, is connected to the direct output of the digital-to-analog converter 3, the output of current source 4 through a divider from (n-1). series-connected resistors 5 are connected to the inverse output of the digital-to-analog converter 3. The output of the input device 6 is connected to the first inputs of all the comparators of two groups 7 and 8 of the P comparators in each. The second output of each comparator 7 is connected to the corresponding output of the corresponding resistor 5. The outputs of the comparators 7 are connected to the information inputs of the switch 9, and the outputs of the comparators 8 are connected to the information inputs of the switch 10. The first output of the clock generator 11 is connected to the inputs of the gates of the comparators 7 and 8 and with the generator input 12 pseudo-random numbers. The output of the pseudo-random number generator 12 is connected to the control inputs of the switches 9 and 1O and to the same information input of the arithmetic unit 13. The second generator output 11 of the clock pulses is connected to the input of the pseudo-random number generator 14, and the output of the generator 14 is connected to the input of the digital-analog converter 3 and to another information input of the arithmetic unit 13. The forward output of the switch 9 and the inverse output of the switch 10 are connected respectively to the input of the element 15 OR, the output of which is connected to the control The input of the arithmetic unit 13. The output of the latter is connected to the recording device 16. The device operates as follows. The measured signal x (1) C-o, (} is centered, is adjusted to the required scale in the input device 6, and is fed to the first strokes of all comparators 7 and 8. Each comparator 7 and 8 work with their own, different from the neighboring level Such a scale of porous levels is created by connecting current sources 1 and 4 through a circuit of series-connected resistors 2 and 5 to the corresponding outputs of transducer 3. The direction of the current in the sources

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T and 4 are selected so that a group of comparators pto numbers, which in definiteparaparatory 7 works with reference voofr-, measured measurement cycle, are connected to terminals that cover the range by changing the paths of switches 9 and 10, corresponding to the signal from O to –q q, and the group is the code at the control input of the commocomparators 8 - with levels in the range of $ tators - pseudo-random number 2k

from O to -c, the scales of the reference levels are MO-Thus, the code of the number that

duliruyutsa pseudo-random output characterizes the reference level in this

the digital-to-analog voltage measurement transform is made up of codes

pad 3. Modulation of the reference levels for d by y numbers, and rk :. At the same time

The group of comparators 7 occurs by direct 0р. It occupies the highest bits in the code with a positive voltage converter, and the number E. The lower bits of the current vary from 0 to + code.

the modulation of the reference levels of the com-E yjjj group by any method of measurement at

Parators 8 are produced by inverting the output - the poisoning code of the arithmetic unit with the voltage of the converter 3, which is 5 logical, ari4n.

the second varies from 0 to –q., the magic device sums the pseudo-voltage at the output of the digital-analogue-random number g, which is present on both

converter 3 is proportional to the pseudo-informational inputs from the already accumulated

random number i, whose code is with you-sum of numbers -After the end of the whole

the pseudo-random number 14 of the measurement of the consisting of n is thus applied to the input of the transducer 3. the accumulation arithmetic unit 13 After each switch, the generated amount multiplies by a constant coefficient of 14 random numbers 14, at the output of each 2 K, extracts the square root

For comparator 7 and 8, the effective signal value estimation code appears.

Tat comparing the measured signal with the supports 25 transmits the registration device 16. The highest level of the comparator. The frequency of the generator clock 14

In each measurement cycle to calculate the pseudo-random numbers is selected n times

No estimate of the average signal power is lower than the oscillator frequency

Only one output of 2 pseudo-random numbers and sampling is used.

comparator from kakdoy group. For the compiler 30 and 7 and 8. Thus, this signal outputs all comparators max use speed

of each group are connected to the inputs of the respective comparators and thus the significantly commuting switches 9 and 10. Reduce the measurement time of the device at the switch 9 output output and inverted digital-analog converter

sny output switch 10 output 35 medium speed. Besides, in

signal of one comparator of each group of the proposed device output signal

7 and 8 through the element OR 15 enters the digital analog converter to change the control input of the arithmetic system within 1 / n of the range

13. changes ± cz of the measured signal, as well as to realize the pseudo-randomness of the digital-to-analogue conversion of information from the compiler 7 users to the number of code less

and 8 to the control inputs of the switches in comparison with the known device,

9 and 10, a pseudo-random code is supplied that contributes to an increase in the speed of 2 k from the pseudo-random generator and the most digital-to-analog conversion of numbers 12, which is clocked by the frequency of the bodies.

Claims (1)

 2 from the second output of the generator. H-akto-When using the proposed impulse pulses 11. The same frequency of the merigele with 8 comparators in each gate 1 computes all the comparators 7 and 8. In the group and the digital-analogue converter & each measurement cycle per arithmetic with the time of order 1 microsecond, device 13 receives the pseudo-slave code with the same accuracy as the prototype, the time & tea number corresponding to the reference quantity of the measurement of this device almost at the level with which in this cycle the comparison is less than that of the prototype ep detectable signal. In turn, the reference level at the second input of the comparators 7 and S depends on the pseudo-random formula of the invention of the number t. and from the point where the comparator is connected to the resistor divider, i.e. from. The digital measurement of the current number of the comparator in each group 7 and 8. The value of the signal containing the input