SU404097A1 - Sha., *> & - ^^^ - ^^ p:; e- - Google Patents

Description

one

The proposed digital-analog slice-line approximator relates to the field of automation and computing. It can be used for piecewise linear approximation of arbitrary functions defined by codes of equal-spaced ordinates.

A device for piecewise linear approximation of functions is known, comprising two serially connected registers, the outputs of which are connected to the inputs of the first and second D / A converters, and a delay line connected by the output and input respectively to the inputs of setting the first and second registers to zero.

However, the low accuracy of this device is due to the fact that in it the approximation is carried out according to a stepwise linear law.

The proposed device is characterized in that it contains an analog integrator, the input of which is connected respectively to the direct and inverse outputs of the first and second digital-to-analog converters, and the output is connected to the output terminal of the device.

This improves the accuracy of the device.

FIG. 1 is a block diagram of the proposed device consisting of registers 1, 2, digital-analog converters 3, 4, analog integrator 5 and a delay line

2

6. Positions 7–9 — respectively, the input of the signals of setting the register 1 to the zero state, the input of the ordinate codes of the approximated function, and the output of the device, on which the result of the approximation is obtained in the form of analog voltage.

FIG. 2 shows timing diagrams for explaining the operation of the device, where a is the stepwise linear voltage produced by the digital-analog converter 3; b - step-linear voltage produced by the digital-analog converter 4; (c) graph of the sum of the stresses mentioned (at the input of integrator 5); g - approximated function at output 9.

Register 1 is designed to receive the ordinate code of the function being approximated, transmitting the previous ordinate of the function to be approximated to register 2 at the time the register is set to zero with a pulse from the output of delay line 6 and controlled by the digital-to-analog converter 3. The input of register 1 is connected with input 8 devices, and output

connected to inputs of digital-analog converter 3 and register 2. Register 2 is assigned to receive codes from register 1 and control digital-to-analog converter 4. Register its output

2 is connected to the input of a digital-to-analog converter 4. Register 2 is set to the zero state by the input 7 of the device and the input of the delay line 6, the output of which is connected to the input of the set to the zero state of register 1. The delay line 6 is for setting impulse delays to the zero state of register 2 for the time determined by the duration of the transient processes in the latter. The digital-to-analog converter 3 (4) is designed to convert the code contained in register 1 (2) to analog voltage. Digital to analog converter 3 has a direct (in-phase) output, and digital-to-analog converter 4 has an inverse (anti-phase) output. The outputs of the converters 3 and 4 are connected and connected to the input of the integrator 5. The integrator 5 is designed to integrate the voltages supplied to its input from the outputs of the digital-to-analog converters 3 and 4. The digital-analogue piecewise-linear approximator works as follows. In the initial position, registers 1 and 2 are set to the zero state. The outputs of the digital-to-analog converters 3 and 4 and the input of the integrator 5 voltage is zero. At output 9, the voltage is also zero. When the first ordinate of the approximated function arrives at the input 8 of register 1 of the digital-to-analog converter 3, the voltage f / i proportional to this code is generated. This voltage is summed with the output voltage of the D / A converter 4. The summation is performed on the internal resistances of the D / A converters 3 and 4. With equal internal resistances, the total voltage at the input of the integrator 5 is t / BX.- | -f /.+0.if/ ,, and at the output 9 of the device U ,, kl (U, + Q} dt MJ, t where k is the proportionality coefficient. Before arriving at the input 8 of the device of the second ordinate by setting the pulse to the zero state, to input 2, the zero state of the register 2 triggers is confirmed, and the release the time determined by the delay line 6 is set to the zero state by register 1. In this case, the code of the first ordinate of the approximated function is transferred from register 1 to register 2, and the inverse voltage f / i is generated at the output of the D / A converter 4. Then from the input 8, the code of the second ordinate of the approximated function enters the first register, and the output of the digital-analog converter 3 forms a voltage U- proportional to the code of the second ordinate. It is summed with the voltage - f / i at the integrator input and the resulting sum (t / 2-Hi) is integrated by the integrator 5 during the time of the second approximation interval. In this case, the voltage at the output 9 of the section from ti to t of the change in the argument can be written out. kU, t + k IVz - U,} dt kU, t, + + k (U, -U,) t At time t, the next reset pulse t / comes to input 7, first to register 2, and then from the line output delay 6, register 1 is set to zero. The code of the second ordinate of the approximated function from register 1 goes to register 2. Then the next, third ordinate code is fed to the input of register I. In the steady state, the output of the digital-to-analog converter 3 has a voltage. t / 3, corresponding to the code of the third ordinate, at the output of the digital-analog converter 4 there is a voltage - U, and at the input of the integrator 5 - their sum is equal to U .., (U, -U,) At the output 9 of the device at an interval from 2 to / 3 the approximate function of the output is obtained: GL + k {U, - U,) (t, + + k jVa - U,) dt kU, t, + k (U, - U,} (t, -t,) + + k (U, -U,) i Thus, the operation of a digital-analogous piecewise linear approximator on the 1st, 2nd and 3rd sections of the approximation is considered. In the subsequent sections of the approximation, the operation of the device is similar.The equation of the approximated function for 1- go u The approximation can be written in the following form: you. (, -.- 1X where, 2, 3, ..., item.) Subject of the Invention A device for piecewise-linear approximation of functions containing two serially connected registers whose outputs are connected to inputs the first and second digital-to-analog converters, and the delay line connected by the output and input respectively to the inputs of the installation in the zero state of the first and second registers, characterized in that, in order to increase 56

Accuracy, it contains analog integrated-second digital-analog converters, a torus, the input of which is connected respectively to the output and is connected to the output terminal with the adjustable and inverse outputs of the first and three devices.

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