SU1246021A1 - Calibrator of phase shifts of amplitude-modulated voltages - Google Patents

Abstract

The invention is intended to form amplitude modulated voltages with an adjustable phase shift jB over a wide frequency range. The purpose of the invention is to expand the functionality due to the fact that in a torus containing a wide-range generator 1, a block 2 of phase shift installations, dividers 3 and 4 frequencies, functional digital-to-analog converters 5 - 6, counters 7 and 8, elements 9 and 10 trigger 11, block 12 set the volume of the counters and shaper 13 modulated signals. 2 IL, (L N9 4 a o y Figure 1

Description

The invention relates to a phase-measuring technique, designed to form amplitude-modulated voltages with a regular G G IM phase shift in a wide frequency range and can be used to create precision measures of phase shifts with amplitude-modulated voltages intended for adjustment and calibration of specialized phase-measuring devices, radio pulse phase meters, as well as in various phase communication systems, automation, radio engineering and

etc.

The purpose of the invention is to expand the functionality, namely the formation of amplitude-modulated voltages.

Figure 1 shows the structural diagram of the device; figure 2 - timing diagrams.

 Amplitude-modulated voltage phase shift calibrator contains a wide-range generator 1, a block 2 of phase shift sets, dividers 3 and 4 frequencies, functional digital-analog converters 5 and 6, counters 7 and 8, elements 9 and 10, trigger P, block 12 setting the volume of the counters and the former (modulator 13 modulating, voltage

The calibrator works as follows.

The signal with frequency f from the output of the wide-range generator T is fed to the inputs of the dividers of frequency 3 and 4, the output stages of which are performed on wave dividers. The division factor of the dividers 3 and 4 is chosen differently 36-10 (p O, 1, 2 ...).

At the initial cascade of dividers 3 and 4 frequencies, sequences of rectangular frequency pulses F are formed.

in time, by an integer number of periods of the oscillator signal 1. These pulse sequences in both channels of the calibrator go to the inputs of functionally search and analogue converters 5 and 6, the weight of each bit of which corresponds to the determined value of the sinusoidal function. If from the output of the imaging unit 13 of modulating voltage to a functional digital-analogue converter 5, a constant voltage is applied, i.e. there is no amplitude modulation, quasi-sinusoidal voltages are generated at the outputs of the transducers 5 and 6, the first harmonics of which are determined by the expressions

and and, sinut;

(one)

360

P U ,, sin (Mt -f K), (2)

where w 21

2ffr

To K, - k.

36-10

- circular frequency of the calibrator output signals, equal to the frequency of the output voltages of dividers, 3 and 4 ;,

-difference of divider codes 3 and 4 frequencies (Kj and K is the current code value, respectively

 dividers 3 and 4.

frequencies).

From the simulations (1) and (2), it follows that the phase shift f between the output voltages U and U2 of the calibrator corresponds to the difference of the K codes and is determined by the expression

360 °

3640- (3)

If you change the value of the difference code K, you can adjust the phase shift f in interruptions; 0-360 ° with discretization

360 °

l1

36 th

(four)

The value of K, which corresponds to the phase: / shift H, is set by unit 2 of phase shift usgnins, which splits the frequency divider 4 into the value of the K code at the time of the zero state of the divider 3. (with K, O and K cr.

The reference voltage of the functional digital-to-analog converter 5 is the output voltage of the shaper 13 of the modulating voltage 11.

At output 1 of the calibrator, a voltage is formed.

55

and U (t) sinut,

(five)

where U, (t) is the modulating voltage of the driver 13,

The shape of the modulating voltage is determined by the shaper 13. The period of this voltage is a multiple of the period of the calibrator output signals and is determined by the volume of the counters 7 and 8. The overflow pulses of the divider. 3 with a frequency F - come through one of the open elements And 9

and 10, for example 9, to the input of the pulse counter 7 (the element And 10 is closed at the same time). Counter 7 through N, periods of signal divider 3 (N is the volume of counter 7) overflows and changes the state of flip-flop 11. The latter closes And 9, opens And 10, and pulses from the output of divider 3 are fed to the input When the counter 8 overflows (after N periods of the divider 3 signal), the trigger 11 is reset and the element 9 is opened, and the element 10 is closed, and the formation voltage of the control voltage Uy (figure 2) entering the driver 13, repeats. Voltage Uj is formed at the output of trigger 11. The volumes of counters 7 and 8, respectively, N, are set by the meter volume setting unit 12 and the pulse duration tj and pause t (figure 2) of the control voltage are determined. Modulating voltage T received at the output of the transformer body 13 is equal to the period of the control voltage Uy and is determined by the expression:

Tm. ty tn T (N, + N. (6)

The former 13 converts the polarization of the rectangular shape Uy into a voltage of the required shape, which modulates the output voltage U of the calibrator.

 Fig. 2 shows the output voltages of the calibrator U,., And U.j when modulated with signals of respectively rectangular or sawtooth shape and an amplitude modulation factor of 100%.

five

to

15

-

0

five

Similarly, the output voltage U in the second channel of the calibrator can be modulated.

Claims (1)

Invention Formula Phase shift calibrator of amplitude-modulated voltages, containing a wide-range generator, phase shift unit and two channels for the formation of phase-shifted sinusoidal signals,. each of which contains a functional digital-to-serial connection to the outputs of the calibrator. A inverter and a frequency divider, wherein the inputs of the frequency dividers are connected to the output of the wide-gap generator, the outputs and inputs of the controls of the phase shift setting unit are connected respectively to the installation inputs and outputs of the second frequency splitter, characterized in that due to obtaining amplitude-modulated voltages, it is equipped with two meters, two AND elements, a trigger, a block for setting the volume of meters, and a modulating -former aprons, the second output of the frequency divider of the first channel through the serially connected first element I and the first counter connected to the first trigger input, and through the serially connected second element I and the second counter to the second trigger input, the first trigger output connected to the control input of the first element And through the modulating voltage driver - with the control input of the first functional digital-analog converter; the second output of the trigger is connected to the control input of the second element AND , and the first and second outputs of the meter volume setting unit are connected respectively to the control inputs of the first and second meters, the second output of the first frequency divider is connected to the control input of the phase shift unit. Editor N. Yatsola Compiled by N “Ageeva Tehred O. Sopko Order 3995/38, Circulation 728 VNIISH State KON JHTeTa USSR for inventions and discoveries 113035, Moscow, Z-ZZ, Raushsk nab., 4/5 Production and printing company, Uzhgorod, st. Project, 4 Proofreader E. Sirohman