SU1682940A1 - Device for measuring phase shift of pulsed microwave signals - Google Patents

Abstract

The invention relates to a measuring microwave technique. The purpose of the invention is to improve accuracy. The device contains adjustable phase shifter 1. adder 2, detector section 4, low harmonic filter 5 pulse repetition rate and indicator 6. A variable dispersive phase shifter 3 is inserted into the device. A harmonic signal is fed to one of the inputs of the adder 2 and, changing the electrical length of the phase rotator 3, the indicator 6 is maximized; Then, without turning on the first signal, the reference signal is fed to the other input of the adder 2 and, by changing the electrical length of the phase shifter 1 by the value of fo, the minimum value is obtained Kazan indicator 6. Seeking phase shift measured between guided and reference signals is calculated by the formula 180 ° . - change in the electrical length of the adjustable phase shifter 1. When measuring in the frequency range, the above operations are repeated at each frequency point. 1 il. (L

Description

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The invention relates to a measuring microwave technique, is intended to measure the phase difference between the first harmonics of complex signals, such as signals of a powerful microwave amplifier device, and can be used in various radio measuring devices, in particular in the design of radio transmitting devices

The purpose of the invention is to increase accuracy.

The drawing shows the structural electrical circuit of the device for measuring the phase shift of pulsed microwave signals.

The device contains an adjustable phase shifter 1, an adder 2, a variable dispersive phase shifter 3, a detector section 4, a low-harmonic filter 5 of the pulse repetition rate, and an indicator 6.

The device works as follows.

First, a signal with harmonics is fed to one of the inputs of the adder 2 and, by changing the electrical length of the variable dispersive phase shifter 3, the maximum indication of the indicator 6 is obtained. Then, without turning off the first signal, the reference signal is changed to another input of the adder 2 phase shifter 1 by the value of / Op and achieve the minimum indication of indicator 6. The desired phase shift between the measured and reference signals is calculated by the formula

px-180 ° -pp.

where pp is the change in the electrical length of the adjustable phase shifter.

In measurements in the frequency range, the frequency-based operations are repeated at each frequency point.

In the case of a phase shift between the second and first harmonics of a signal equal to ± П / 2, a phase shift between the third and first harmonics of a signal equal to П, and a measured phase shift between the first harmonics of two signals equal to 0 or П, the measurement errors due to higher harmonics are zero. With this phasing, the maxima of the sinusoids of the first and higher harmonics coincide in time, which ensures the independence of the results of phase measurements using the above method from the presence of higher harmonics in the signal. Since the dispersive phase shifter is included in the total signal circuit, it does not introduce errors to the measurements due to the VSWR.

Claims (1)

Invention Formula A device for measuring the phase shift of pulsed microwave signals, comprising a series-connected adjustable phase shifter and an adder, a series-connected detector section, a low harmonic filter of the pulse repetition frequency and an indicator, the second input of the adder and the input of the adjustable phase shifter being the first and second inputs of the device, respectively the fact that, in order to increase the accuracy, the output of the adder is connected to the input of the detector section through a combined variable dispersion function spruce.