SU1226610A1 - Adaptive ripple filter - Google Patents

Abstract

The invention relates to radio engineering and can be used in automatic control systems. The purpose of the invention is to improve the dynamic characteristics. The input signal is fed to the first subtraction unit (BV) 1, in which the output signal from the adaptive 1C is subtracted from it: o:

Description

it has a smoothing filter. The difference signal from BV 1 is fed to the first sign detector (DZ) 2 and through the multiplier I7 to the second integrating amplifier (IC) 8. The smoothed signal from IC 8 goes to the output of the adaptive smoothing filter w. The signal with DZ 2 in the form of + or -1 is fed to the multiplier 4, which receives the same signal through delay element 3. If the factors are of the same sign, then the signal +3 from the multiplier 4 enters the second BV 5. PS 6 smooths the signal of the second BV 5, which through the scale amplifier 7 goes on the fifth BV 21 The output signal of the second PS 8 is subtracted in the third BV 10 from the delayed second delay element 9. This difference signal processes 1

The invention relates to radio engineering and can be used in automatic control systems,

The purpose of the invention is to improve the dynamic characteristics,

Fig. 1 shows a structural electrical circuit of an adaptive smoothing filter; FIGS. 2 and 3 show its transient functions and amplitude-frequency characteristics (AFC), respectively.

- The adaptive smoothing filter contains the first subtraction unit 1, the first detector 2 characters, the first delay element 3, the first transceiver 4, the second subtraction unit 5, the first integrating amplifier 6, the first large-scale amplifier 7, the second integrating amplifier 8, the second element 9 delays, the third block 10 of the subtraction of the second detector AND sign, the third element 12 of the delay, the second transceiver 13, the fourth block 14 of the subtraction, the third integrating amplifier 15, the second large-scale amplifier 16, the third I7 and the fourth 18 multipliers, the fourth 19 and the fifth 20, inte gc is similar to the signal from the output of the first BV 1 using the second. The DZ 11, the second multiplier 13, the third delay element 12, the fourth BV 14, the third PS 15 and the second scaled amplifier 16 arrive at the other input of the second BW 21. The signal of the second BV 21 corresponding to the statistical time constant of the adaptive smoothing filter is compared in the fifth PS 20 from the current time constant, which is obtained at the output of the fourth remote control 19. The fourth remote control input 19 receives signals from the third and fourth multipliers 17 and 18. -Control signal to eliminate the difference between the current and specified values PICs time constant of the fifth to the DUT 20 is fed to a third multiplier 17. 3 yl.

five

0

output amplifiers and fifth subtraction unit 21.

Adaptive smoothing filter works as follows.

The input signal is fed to the input of the first subtraction unit 1, in which the output signal of the adaptive smoothing filter is subtracted from it, and the resulting difference is fed to the input of the third multiplier 17 and to the input of the first detector 2 characters. At the output of the second integrating amplifier 8, a smoothed signal is obtained, which is fed to the output of the adaptive smoothing filter. The difference signal from the output of the first reading block 1 is fed to the input of the first detector 2 characters, the output of which is a signal of either +1 or -I, which is fed to the input of the first delay element 3 and the second input of the first multiplier 4, whose output is equal to factors of one sign, and, if they are of a different sign. At the output of the first integrating amplifier 6, a smoothed signal of the second subtraction unit 5 is obtained. Which through the first large-scale amplifier 7 is fed to

31226610

input n of that block 21 subtract

determine the rate of change

st but

and

the smoothed signal the output signal of the second integrating amplifier 8h is stored in the second delay element 9, and then the delayed signal

is subtracted in the third subtraction unit 10 from the output of the adaptive smoothing filter.

The obtained difference signal is processed similarly to the output signal of the first subtraction unit 1.

The output of the third integrating amplifier 15 through the second large-scale amplifier 16 is fed to the second input of the fifth subtracting unit 21.

The gain stabilization circuit of the M5y adaptive smoothing filter circuit consisting of the third 17 and fourth 18 multipliers, the fourth 19 and fifth 20 integrating amplifiers determines the current time constant of the adaptive smoothing filter T obtained from the fourth integrating amplifier 19 on the input and output signals of the adaptive smoothing filter, compares it with the time constant obtained from the statistical characteristics of the output of the fifth subtraction unit 21, taking into account the adjustable level T supplied to the third input of the fifth integrating amplifier 20.

The stabilization of the dynamic characteristics of the filter is provided by measuring the current value of its constant time, comparing this value with a predetermined value of a given time at the fifth integrating amplifier 20 and away from its control signal output to eliminate the difference between the current and the fixed values of for the third multiplier 17.

The predetermined time constant value is formed by summing the adjustment signal T with the output signal of the fifth block 21 of the subtraction of the constant time correction circuit.

The current constant-time value of the adaptive smoothing filter is measured by an identification circuit consisting of a fourth multiplier 18 and a fourth integrating amplifier 19. The operation of the identification device is described by the relations

and

(9

 --- (U ,, - and and ,,);

"H

and and.

t

 where

K,; u.

- (T

t

go

and

20

- and,

).

and

20

and,

(7

and to

17

Ed 19 (1) output signals of the integrating amplifiers 19 and-20, respectively; the output of the first subtractor 1, the output of the third multiplier 17, and its transmission coefficient, respectively.

For the stable operation of the device identification scheme, the following conditions must be met:

and, (0) 4 and, (O) or in general

Sign and ,, (О) sign and, (О).

Then, for fixed values

thirty

t- (and „

- and; and ..) Oh,

from where

Have

and,

Substitute in

and"

this expression is value

and., from expression (1) we obtain

and

nineteen

-

The integration process ends

in the case when

W

Substituting in the expression (1) U T, we find the Expression for

and

° K, j

The equivalent value of the transmission coefficient of the third multiplier 17 is equal to

K ya - and - eq and 1

T + Uo

K.

 3 "A

 iciA - о J21 where U is the output signal of the nth block

21 subtraction.

Therefore, in the proposed device, the value of a given time given by the signal TO + U is stabilized by influencing the transmission coefficient of the multiplier 17.

S12

The proposed device makes it possible to reduce the number of blocks and adjustments. The scheme of the known device provides for one adjustment in each channel by adding to a variable signal passing through each of them a certain constant value selected during adjustment (PO and TO) In addition, each of the control channels contains two small amplifiers and one setter each, the coefficients of which are also selected experimentally.

If it is necessary to change the statistical characteristics of the out-of-turn signal, then it is necessary to reconfigure all adjustable parameters (scale factors and settable signals | 3о and TQ). The total number of adjustments in the scheme of the known device is 8.

The proposed device contains two times smaller scale amplifiers, has no knobs and has only one adjustment signal T j fed to the third input of the fifth integrating amplifier 20. In addition, in the proposed device the number of adjustments is 3,

Claims (1)

Invention Formula An adaptive smoothing filter containing the first subtraction unit connected in series, the input of which is the input of the adaptive smoothing filter, the first sign detector, the first delay element, the first multiplier, the second input of which is connected to the output of the first sign detector, the second power unit and the first integrator : nd amplifier, whose output is connected to the 4 second input of the second unit, subtract 610fe Neither 5 are connected in series to the second integrating amplifier, the output of which is connected to the second input of the first subtraction unit and is the output of the adaptive smoothing filter, the second delay element, the tertiary subtraction unit, the second input of which is connected to the output of the second integrating amplifier, the second sign detector 5 third element delays, E; the second multiplier, the second input of which is connected to the output of the second sign detector, the fourth subtraction unit and the third integrating accelerator} whose output is connected to the second the input of the fourth subtraction unit, as well as the first and second large-scale amplifiers and the fifth subtraction unit S characterized in that, in order to improve the dynamic characteristics, a third multiplier is inserted in it, connected between the output of the first subtraction unit and the input of the second integrating amplifier, serially connected and included between the output of the first subtraction unit and the second input of the third multiplier — the fourth multiplier, the fourth integrator of the Ruyundai amplifier, and the fifth integrating amplifier, with the third output The first multiplier is connected to the second input of the fourth integrating amplifier, the output of which is connected to the second input of the fourth multiplier, the first and second large-scale amplifiers are connected between the outputs of the first and third integrating amplifiers and the first and second inputs of the fifth subtractor, respectively, the second input of the fifth integrating the amplifier is connected to the output of the fifth subtraction unit, and the third input is the fifth. the integrator amplifier is the input of the adaptive anti-aliasing filter control. Gd Zj. / 0.1THS0.60.8 Fmg.2 ly;, 5