SU705469A1 - Device for determining correlation function - Google Patents

Description

I

The invention relates to special analog devices for measuring the correlation function of centri ovsnestine stationary random processes.

A device for determining the correlation function of centered random processes is known that implements a compensation method for minimizing the dnsperse of error l.

In the correlation devices of the compensation type, the errors of individual nodes of the correlating meter have a bearing on the measurement accuracy of the correlation function, especially when using analog equipment.

The accuracy of obtaining the values of the correlation function in analog devices of the compensation type is mainly determined by the zero drift of the correlator nodes and the errors introduced. block lag and quadratic transformation (quad).

The closest to the invention to the technical essence is the device

to determine the correlation function, which contains the delay unit whose input is the first input of the Device, and the output is connected to the first input of the squaring block of the signal difference, the voltage divider whose input is the second input of the device, and the averaging zero is an indicator. The CroMe prototype contains a second quad.

The device has the following disadvantages:

- to implement a device, two quadrs are required, which makes the device cumbersome;

-quality errors introduced by quadrants. may have different signs, therefore

total maximum error. devices due to the lack of quality of quartzors are equal to twice the error of the quad;

-the requirement of identity is characterized by fm. Both quadratures make it difficult to manufacture and tune the device as a whole, and failure to comply with this requirement leads to a decrease in the accuracy of the device. The purpose of the present invention is to improve the accuracy of the device. This goal is achieved by the fact that a source of switching signals and an electronic key are inputted into the device, the inputs of which are connected respectively to the zero potential bus, to the output of a voltage divider, to the forward and inverse outputs of the erection unit and the square of the signal difference signals, the first output of the electronic key is connected to the second input of the squaring unit of the difference of signals, and the second and third outputs are connected respectively to the first tf second inputs of the zero averaging indicator. The drawing shows a block diagram of the device. , The device contains a lag unit 1, a voltage divider 2 (reohord with a grounded midpoint), a squaring block of a signal difference difference 3, an electronic switch 4, a source of switching signals 5 and the zero averaging indicator 6. The output of the lag unit 1 is connected to the first input of the unit squaring the difference of the signals 3, the slider 2 is connected to the first input of the electronic key 4, the second input of the electronic key is grounded, the first output of the electronic key is connected to the second input of the squaring unit, the difference of the signals 3 The first output of the unit 3 is connected to the third input of the electronic key 4, and the second output of the unit 3 is connected to the fourth input of the electronic key. The second output of the electronic key is connected to the first input of the averaging zero indicator, and the third output of the electronic key is connected to the second input of the averaging zero indicator. The control input of the electronic key is connected to the output of the source of the switching signals. The device works as follows. At the terminals of the device, the input signal U (t) is supplied, which is compensating. The output signal of the reochord 2 is equal: and - v. R R where R is the impedance of the reichord; R. is a part of resistance between the reoword engine and the midpoint. The Up signal will be reset in the initial state via the electronic key 4 to the first | input of block 3, the second input of which receives the second signal V (f-5) from the output of the delay unit 1. In block 3, the signal V (iD) is read from the Up signal The resulting difference is squared. As a result, at the output of the squaring block, the differences of signals 3, as well as at the second output of the electronic key 4 at the output of the averaging zero indicator 6, a signal is generated: (ir) - and p-2UpV (i --C) -tV Vx :). The electronic switch 4, controlled by the source of switching signals, connects the first input of the squaring unit to the difference of signals 3 alternately, then to the rheochord engine, then to the grounded point, therefore, at the first output of unit 3 relative to the second output, signals A2- V {-fc-t). The second and third outputs of the electronic key are connected respectively to the third and fourth inputs synchronously with the connection of its first output to the first input. Synchronously with the connection of the first output of the electronic key to the second input, its second output is connected to the fourth input, and the third output to the third input. In one key position, the first input of the averaging zero indicator b is connected to the first output of block 3, and the second input of the averaging zero indicator is connected to the second output of block 3; in a different key position, the first input zero is connected to the second input of block 3, and the second zero input - the indicator is connected to the first output of block 3. Thus, the AJ and - Aj- signals alternately arrive at the null indicator. Taking into account that the indicator b is proportional to the average value of the signals received on it, at the same time neither the electronic key 4 in each of its two states, the indicator readings, is determined by the following expression: AG .l AgT; .0.5-The position of the slide bar changes until the reading, zero — of the indicator becomes zero that corresponds to A - A. Substituting the values of A and A into this equality, we have: Uj-2UpV (t-r) zO.

Taking into account that Up-L-c, we get:

eleven.

Utb Vtt-t) 2T1

Since U (t) is the value of centering, the value of U (t) is the variance of this value, and the value is its correlation function.

The implementation of the device is simple, the newly introduced elements can be easily implemented on field-effect transistors.

The described device for determining the correlation function is rather simple in its technical design, it allows to increase the accuracy of the determination of the correlation function and simplify the manufacture and commissioning of the device as a whole.

Claims (1)

Invention Formula A device for determining the correlation function, comprising a lag unit whose input is the first input of the device and the output connected to the first input of the block construction in quad-,. The signal difference difference, the voltage divider, whose input is the second input of the device, and the averaging null indicator, is characterized in that, in order to be accurate, the device is supplied with a source of wired signals and an electronic key, whose inputs are connected respectively to the bus of zero Potential , with the output of the voltage divider, with the direct line and inverse outputs of the squaring block of the difference of signals and with the switching signal trigger, the first output of the electronic key is connected to the second input of the elevator neither the squared difference of signals, and the second and third outputs are connected -. respectively, to the first and second inputs of the averaging zero indicator. Sources of information taken into account in the examination1. USSR author's certificate number 206190, cl. G 06 Q 7/19, 1967. 2 USSR author's certificate N 4O5113, cl. 6 06 Q 7/19, 1972 (prototype).