SU813448A1 - Device for determining correlation function discrete step - Google Patents

Description

(54) DEVICE FOR DETERMINING THE STEP OF THE DISCRETENESS OF CORRELATION FUNCTION

The invention relates to determining the likelihood characteristics of random processes in radio devices and is intended for experimental studies of random processes, in particular for measuring the discreteness step of the mutual correlation function (ICF) with its subsequent use in correlators,

A device for determining the discreteness step of a correlation function is known, which contains a pulse shaper and a counter 1,

The main disadvantage of this device is the impossibility of determining the discrete step of the CCF.

Most conclusively to the proposed device is a device containing a high-pass filter, which is connected via a pulse generator, a coincidence circuit, and a switch to a counting one. by a circuit or with a counter, the output of the high-pass filter is also connected via a rectifier, with an analog-to-digital converter, the second input of which, after coincidence, with a clock generator, is connected with an analog-digital converter with a pulse counter. In addition, the output of the scaling circuit is connected to a single trigger input, and the zero trigger input, via the trigger button, is connected to a polling pulse generator, and the trigger output is connected to a matching circuit. The device allows determining the discrete step for the autocorrelation function of a normal random process, which is based on multiplying a given approximation error by the average number of zeros of the centered process {21,

However, this device is fundamentally impossible to measure the discrete step of the CCF.

The purpose of the invention is to expand the functionality by determining the discrete step of the mutual correlation function of stationary normal random processes with a given approximation error.

The goal is achieved by the addition of a high-pass filter, a pulse driver, three coincidence circuits, two analog-to-digital converters of an analog arithmetic unit consisting of

two logarithmic amplifiers, a summing amplifier, a subtractor amplifier and an anti-log amplifier, a registering device, the high-pass filters through the pulse shapers connected to the coincidence circuits, allowing

the input of which is connected to the forward input of the trigger, the outputs of the matching circuits are connected to pulse counters, the outputs of the pulse counters through the matching circuits, digital-to-analog converters, logarithmic amplifiers are connected to the outputs of the summing amplifier, and the enabling inputs of the matching circuits are connected to the inverse trigger input, the output of the summing amplifier through. the amplifier subtractor, anti-log amplifier and analog-to-digital converter are connected to the input of the registering device, in addition, the zero input of the trigger is connected via a timer to the unit of time and through the coincidence circuit with the clock generator, the output of which through the trigger button is connected to the single input of the trigger.

The drawing shows a functional diagram of the proposed device.

The device consists of filters 1 and 2 of the upper frequencies, which are connected to a generator of 3 and 4 pulses and through elements 5 and 6 with counters 7 and 8 pulses, blocks 9 and 10 elements And with digital-analog converters 11 and 12 and with an analog arithmetic unit consisting of logarithmic amplifiers 13 and 14, connected to summing amplifier 15 and amplifier-subtractor 16, connected to anti-log amplifier 17, the arithmetic unit through analog-to-digital converter 18 is connected to recording; A third device. The third input of the analog arithmetic unit 20 is connected to a constant voltage source 21. The operation of the device is controlled by the analysis time setting unit 22.

The proposed device works as follows.

On the signal from the first output of block 22, the task of analysis time is opened, elements 5 and 6 are opened. Thus, the circuit is transferred to the measurement mode. Filters 1 and 2 cut off the constant components of the studied processes, thereby bringing them to zero level. The formers of 3 and 4 pulses form pulses when each process crosses the zero level. These pulses accumulate in counters 7 and 8. At the end of the analysis time, a signal is formed that opens the blocks AND 9 and 10 elements, through which the codes from counters 7 and 8 are converted into a constant voltage by means of digital-analog converters 11 and 12. The analog arithmetic unit 20 consists of logapif / Iicheckix amplifiers 13 and 14, summing amplifier 15 with the gain of the two-input amplifier 5 -vychitatel 16 antilogarifmeticheskogo amplifier 17.Rabota analog arithmetic unit based on perevoQ de linear measurements in a logarithmic scale, whereby the dividing step , multiply, extract the root is replaced by the summation and subtraction operations with the corresponding linear coefficients. The second input of the subtractor amplifier is supplied with the voltage Uon .., which corresponds to the value of the approximation error. Transformed

- the arithmetic unit signal through

Analog-to-digital converter 18 is fed to a registration device 19, where the value of the discreteness step of the mutual correlation function with a given approximation error is recorded.

The proposed device for estimating the CCF allows one to determine the discreteness step of the CCF without the need for a large amount of a priori information about the processes under investigation, which shortens the period of time usually spent on obtaining primary information about random processes. The implementation of the device on high-speed integrated circuits allows it to be used in conjunction with a computer operating in real time in automated control systems.

Claims (2)

Invention Formula A device for determining the step of discreteness of the correlation function, containing an analog-to-digital converter, the output of which is connected to the input of the recording unit, a high-pass filter, the input of which is the first input of the device, 1 output is connected via a pulse former to the first input of the first element I, the second input of which is connected to the first output of the analysis time block, the output of the first element I is connected to the input counter, characterized in that, in order to extend the functionality by defining the step of discreteness of the mutual correlation function, The device introduced the second element And, two blocks of elements And, the second high-pass filter, the second pulse shaper, the second counter, two digital-to-analog converters, a source of constant voltage and an analog arithmetic unit whose inputs are connected respectively to the outputs of digital-analog converters and to a constant source voltage, and VYLOT is connected to the input of an analog-digital converter, the input of the second high-pass filter is the second input of the device, and the output is connected to the input of a second photo tors, pulses, whose output is connected to the first input of the second AND gate, the second input of which is connected to the first output of the analysis time specifying unit, an output of the second AND element is connected to the input of the second counter, the outputs of the first and second counters connected, respectively, to the first inputs of the first and second blocks of the And elements, the second inputs, which are connected to the second output of the analysis time block, the outputs of the And blocks of the elements, are connected respectively to the inputs of digital converters “ Sources of information taken into account during the examination 1. G. Y. Iyirsky Hardware characterization of random I r processes. M., Energie, 1972, p.209, 2. USSR author's certificate 279211, cl. H 03 K 21/10, 1969 (prototype).