SU85190A1 - Range phase shifter - Google Patents

Description

The purpose of this device is to obtain from one voltage the two voltages applied to it, which are shifted by 90 ° relative to the other, while maintaining the amplitude of the voltages being relieved in a certain frequency range. It is a circuit that has a reduced reactive two-port circuit at the input, which is used to obtain a constant value of the input impedance in a certain frequency band.

The main difference of the proposed device from the existing ones is the use of the T-shaped bridge circuit used in it, not as a phase-equalizing phase, but as a phase-shifting circuit, thereby achieving a significant simplification of the device circuit. For this purpose, the inductance in the T-shaped circuit, connected in series with the capacitor, is replaced by a purely resistive resistance, from the terminals of which the voltage shifted by 90 ° is removed relative to the voltage removed from the voltage resonance circuit.

In the drawing is a schematic diagram of the proposed device.

The inductances LI and La of the capacitance Ci and Ca of the device form a semi-linear band-pass filter loaded on the resistance R and calculated for the passband much larger than the specified frequency range. In a given frequency range, this circuit has a purely active input impedance, almost not dependent on frequency, which ensures a constant current in the circuit under consideration.

The voltage Ui JR at constant current will also be constant.

Voltage Vol is the sum of the voltage on the capacitor and the voltage induced in the coil Ll, which, being out of phase by 180 ° relative to the voltage on the coil LI, will coincide in phase with the voltage on the capacitor. Thus, the device provides a phase shift of 90 ° between the voltages f7i n IJ-2.

As the frequency increases, a decrease in the voltage across the capacitor is compensated by an increase in the voltage across the coil. The largest non-uniformity in a given frequency range is determined by the formula

And l + fo

22 V FI F-i

where / i and / a - border frequency range.

Present Invention

A range phase shifter having a reduced reactive two-pole input to provide a constant input resistance in a certain frequency band is different because, in order to convert the phase-equalizing T-bridge bridge used in it into the phase-shifting, in the specified T-shaped loop the inductance, connected in series with the capacitor, is replaced by a purely active resistance, from the terminals of which the voltage is removed with a phase shift in relative voltage, lower aemogo with the resonance circuit voltage.