SU728090A1 - Discrete phase calibrator - Google Patents

Description

(54) DISCRETE PHASE CALIBRATOR

The invention relates to a phase-measuring technique — and can be used to create an exemplary phase-measuring apparatus. A two-phase generator with graduated phase shifters is known, which contains a generator and a phase shifter composed of several phase shifters 1. A two-phase generator with a single-channel phase-measuring device is known, which contains a generator whose output is connected to the input of a frequency divider and a vertical deflecting plates electron-type the oscilloscope beam tube, and a voltage C is applied to the horizontal deflection plates; the output of the phase shifter, the input of which is connected to the output of the frequency divider 2. This device, as the pre-propagating one, is characterized by insufficient accuracy in the reproduction of discrete phase-shift angles in a wide range of working frequencies. The aim of the invention is to improve the accuracy and expansion of the frequency range. This is achieved by the fact that a discrete phase calibrator containing a generator, the output of which is connected to the input of a frequency divider, and a phase shifter, is equipped with a frequency multiplier, a multiplier unit, a shaper of short pulses, a selective voltmeter and a resonant amplifier, and the output of the frequency divider through serially connected frequency multiplier, phase shifter and the short pulse shaper is connected to one of the inputs of the multiplication unit, the second input of which is connected to the generator and the output through the resonance A second amplifier is connected to the input of a selective voltmeter. The drawing shows a block diagram of a discrete phase calibrator. The discrete phase calibrator contains a generator 1, a frequency selector 2, a phase shifter 3, a frequency multiplier 4, a multiplication unit 5 ,. shaper short pulse b, selective voltmeter 7 and the resonant amplifier 8. Discrete calibrator, the phase works as follows.

The sinusoidal voltage from the generator 1 with the oscillation frequency f (K + 0.5) is applied to the series-connected frequency divider 2 with the division factor (2K + 1) and frequency multiplier 4 with the multiplication factor 2, as well as to the input of the multiplying unit 5. The low-frequency signal from the output of frequency multiplier 4, whose frequency is equal to f, is fed to the input of the phase shifter 3 and the output terminal. At the output of the phase shifter we have a signal

Ugy Uwsin (2irH + 4)

where H is the phase that changes within O-ZBO C.

The signal from the output of the phase shifter 3 is fed to a pulse shaper 6. A periodic sequence of short pulses with a following frequency f is fed to the input of multiplier 5. At the output of multiplier 5, we will have a periodic output of 0.5 n pulses. When the phase of a periodic sequence of short pulses changes, the temporal position of which is rigidly connected with the sinusoidal signal at the output of the phase shifter 3, the amplitude of the alternating pulses changes and reaches a minimum.

The dp determinations with high accuracy of the minimum amplitude of opposite-polarity pulses at the output of multiplier 5 are used in series with the connected resonant amplifier 8 and the selective voltmeter 7 tuned to the frequency 0.5. The fixture has the minimum readings of a sepa- rate voltmeter 7, it is possible to reproduce with high accuracy the increment of the phase angle of the output signals of the calibrator with a resolution of 360 (2K + 1). The discrete phase calibrator makes it possible to increase the accuracy of reproduction of discrete increments of the phase angle to 0.02 ° in the operating range: frequency to 10 MHz.

Claims (1)

1.Koltik ED, Measuring two-phase alternating current generators. M., Publishing House of Standards Committee, 1968, p. 89-96J 2, Koltik E.D. Measuring two-phase alternators. M., Publishing Committee. standards, 1968, p. 96-107.