SU1188761A1 - Square-law function generator - Google Patents

Abstract

A SQUARE containing a frequency-width-pulse modulator, made in the form of a first adder, a first integrator and a first relay element connected in series, the output of which is the output of a frequency-pulse-width modulator and connected to the first input of the first adder, the second input of which is the input of the frequency-pulse-modulator and the input of the quad, connected in series the second adder, the second integrator, the amplitude modulator and the second relay element, the output of which is connected En to the first input of the second adder, an element of equivalence and a pulse shaper, whose input is connected to the output of the first relay element and to the first input of an equivalence element, to the second input of which is connected the output of the second relay element, the output of the pulse shaper is connected to the control input of the amplitude modulator, the output of the element of equivalence is a quad output, characterized in that, in order to increase the operation accuracy I, the output of the first relay element is connected to the second input (L of the second ummatora.

Description

The invention relates to electrical computing devices and can be used in analog computers.

The purpose of the invention is to improve the accuracy of work.

FIG. 1 shows a functional diagram of the proposed quad; in fig. 2 - amplitude characteristic; in fig. 3 and 4 timing charts of signals.

FIG. 1 denotes first and second adders 1 and 2, first and second integrators 3 and 4, first and second relay elements 5 and 6, amplitude modulator 7, pulse shaper 8, equivalence element 9, input 10, output 11, frequency-1iro- pulse modulator 12.

Quad works as follows.

The first and second relay elements 5 and 6 are made with symmetric threshold switching ±, Bi and ± B2, respectively, and a non-inverting hysteresis loop.

The pulse shaper 8 is designed to generate a pulse of short duration synchronously with the time of the end of the sampling interval (period) of the pulses at the output of the first relay element 5.

The amplitude modulator 7 generates pulses at the output, the duration of which corresponds to the duration of the signal at the output of the pulse shaper 8, and the amplitude is proportional to the signal level at the output of the second integrator 4.

The sign of the output pulses of an element equal to 9 corresponds to the sign of the product of the signals at the outputs of the first and second relay elements 5 and 6.

The quadrator is designed to implement the functional dependence of the form (Fig. 2).

(-K, -), (1)

where ho is the quad input;

K; is the resulting quadrant transfer coefficient.

The first adder 1, the first integrator 3 and the first relay element 5 are a frequency-width-pulse modulator 12. In the absence of a signal at input 10, the output signal Ouse (1) of the first integrator 3 has the form of a symmetrical saw (Fig. 3, a) the amplitude of which is limited by switching thresholds ± Bi of the first relay element 5. In this case, at the output of the first relay element 5, a "square wave" signal Y5 (t) is formed with a zero value during the period of self-oscillations (Fig. 3a).

The cascade including the second adder, the second integrator 4, the amplitude modulator 7 and the second relay element 6 also belongs to the class of self-oscillating frequency-lattice-pulse systems and is designed to convert the output pulses of the first relay element 5 into the second frequency-pulse-width carrier .

The switching times of the second relay element 6 are synchronized with the time points of the end (beginning) of the next sampling interval of the signal at the output of the first relay element 5. This is realized with the help of pulse generator 8 and amplitude modulator 7.

The output signal of the pulse shaper 8 (ftig. 3.6) is subjected in the amplitude modulator 7 to modulation at the level of the sweep signal (Fig. 3, c) generated at the output of the second integrator 4.

In the time intervals ti, {3 ... (Fig. 3, c), the rate of change of the output signal of the second integrator 4 is determined by the sum of the signals (Fig. 3, a) and (Fig. 3, c) at the outputs of the first and second relay elements 5 and 6, and in the intervals t2, t4, ... depends on the difference of these signals. As a result, the sweep signal 0 is a broken saw where the break points correspond to the instants of time for changing the sign of the signal at the output of the first relay element 5.

The change in the sign of the pulses at the output of the second relay element 6 (Fig. 3, c) occurs at the moments when the output signal of the amplitude modulator 7 exceeds the thresholds B2 (Fig. 3, c) and has the form of a lattice function with an amplitude normalized by the output signal of the second integrator 4 ( scrap on the line of Fig. 3, c).

The element of equivalence 9 generates at output 11 a signal with an average zero value (Fig. 3, d).

The presence of an informative signal at the input 10 (Fig. 4, a) entails a change in the derivative of the sweep at the output of the first integrator 3.

In one of the intervals of the scanning converter, the rate of change of the signal at the output of the first integrator 3 (Fig. 3, a) 0 is determined by the difference of the input and feedback signals, and in the other interval is determined by the sum of these signals.

As a result, the duty cycle and the pulse period at the output of the first 5 relay element 5 change. During the period of self-oscillations, the constant component of this signal is proportional to the level of the signal at input 10.

The presence of a constant component of the signal at the output of the first relay element 5 entails a change in the period and duty cycle of the pulses (Fig. 4, c) at the output of the second relay element 6. At the same time, the constant component of this signal also reaches a level proportional to the signal at input 10 (for a time equal to several pulse sampling intervals). As a result, the constant component (Fig. 4) of the pulses at the output of And corresponds to 311188761.

J4

the square of the informative signal relay element 5 of its own

at the entrance 10. frequency of self-oscillations should be chosen

To exclude the mode of the forced frequency-width-modulated quadrature synchronization module by the signal from the first 12.

equal or lower frequency of self-oscillations

five,

and oh,

P P P P O P O

S,

at,

tj

tlf

(,

FIG. 3

Vb, o

z

-Si

z

X7 LDP n

G / 7 - /

ug

Claims (1)

SQUARE containing a pulse-frequency-pulse-frequency modulator, made in the form of a series-connected first adder, a first integrator and a first relay element, the output of which is the output of a pulse-frequency-pulse-width modulator and connected to the first input of the first adder, the second FIG. 1 input of which is an input of a pulse-frequency-pulse-width modulator and a quadrator input, a second adder, a second integrator, an amplitude modulator and a second relay element connected in series to the first input of the second adder, an equivalence element and a pulse shaper whose input is connected to the output of the first relay element and with the first input of the equivalence element, to the second input of which the output of the second relay element is connected, the output of the pulse shaper is connected to the control input of the amplitude modulator, the output is the output of the equivalence element squarer, characterized in that, in order to increase the accuracy of the work output of the first reley- § Nogo element connected to the second input of the second adder.