SU377704A1 - DEVICE FOR MEASUREMENT OF DISPERSION OF RANDOM - Google Patents

Description

one

It is known that devices based on the algorithm are used to measure the dispersion of stationary ergodic random orocesses.

Dlx

(Xk - Xf,

n - l

where n is the sample size of the measurement,

X is the mathematical expectation (or time average) of the sample.

Such devices include an input signal block, a device, a centering implementation of the process under study, a quad and an integrator (averaging device).

A disadvantage of the known devices is the occurrence of a significant measurement error due to the presence of a certain displacement of the average value (the nonstationarity of the mathematical expectation) in the measurement process, while the stationarity of the process variance is usually not affected.

The essence of the proposed invention is that instead of a device centering the implementation of the process under study, in order to increase accuracy, a subtraction unit and a delay unit for one cycle are installed between the input signal block and the quad. This allows one to free oneself from the error resulting from the nonstationarity of the mean value when measuring the dispersion of random processes.

The device performs measurement according to the algorithm.

one

 2 (p-1)

The drawing shows a block diagram of the proposed device.

The device contains an input signal control unit / block, a subtraction block 2 for obtaining a difference (Xfe +, t - ffe) between the present and a previous value, a delay block 5 for storing the previous value, a quad 4 for squaring the difference (xk +. - Xk), integrator 5-averaging device and display unit 6.

The investigated implementation is fed to the input device, the output of which is connected to one of the inputs of the subtraction unit, and to the other input through the delay unit for one cycle. At the output of the subtraction unit, the difference between the present and previous values of the measured process is obtained. This difference is squared and fed to a secondary device (integrator), the output of which is connected to the unit.

enclications.

Subject invention

A device for measuring the dispersion of random processes, containing an amplitude control unit for the input signal and a series-connected quadrant, integrator and display unit, characterized in that, in order to improve the accuracy of the device, it additionally contains a subtraction unit and a delay unit whose output is connected to one input the subtraction unit, and the input to the output of the input control unit and to another input of the subtraction unit, the output of which is connected to the quad input.

Hm