SU1617388A1 - Apparatus for measuring directional pattern of aerial - Google Patents

Abstract

The invention relates to an antenna measurement technique and can be used to measure a radiation pattern / antenna / antenna mounted on a rotator. The purpose of the invention is to increase accuracy while simultaneously expanding the dynamic range of measurements. A device for measuring the antenna pattern includes a signal generator 1, the output of which is connected to the input of auxiliary antenna 2, the antenna under investigation / IA / 3, mounted on the rotary stand 4, serially connected mixer 5, the first input of which is connected to the output of IA 3, intermediate frequency amplifier 6 / UPCH /, peak detector 7, block 8 sample storage / BVH / and indicator 9. The oscillator 10 oscillating frequency / GKCH / connected by the first output to the second input of the mixer 5, and the second output - to the input "Reset" of the peak detector 7 and the input "Sampling" BVH 8. Is olzovanie sweep oscillator 10 as eliminates the effects of frequency offset signal generator 1 on the measurement accuracy and also broaden the dynamic range by allowing despreading the IF amplifier strip 6 and, therefore, reduce the noise level. 2 Il.

Description

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ABOUT)

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1

The invention relates to the technique of antenna measurements and can be used to measure the radiation pattern (NF) of an antenna mounted on a rotating stand.

The purpose of the invention is to improve the accuracy with a simultaneous expansion of the dynamic range of measurements: In FIG. 1 shows the structural I electrical circuit of the device for measuring I and antenna; FIG. 2 - dependence of voltages on time. ; Device For measuring the antenna antenna (FIG. 1) includes a generator of 1 signal, connected to auxiliary antenna 2, the antenna 3 under study is mounted on a rotary stand 4 and connected in series to the transmitter 5, intermediate amplifier 6; , peak detector 7, sampling-storage unit ji8 (BVH) and indicator I 9, Perv output of the 10 oscillating frequency generator (HKCH) is connected to the second; mixer input 5. The output of the HKCH 10 is connected to the second input of the mixer Reset peak detector 7 and input sample BVH B.

A device for measuring the antenna DN works as follows

Signal generator 1 is connected to auxiliary antenna 2, which emits a signal received by the research; Antenna antenna 3 mounted on the swivel stand 4

The signal from the output of the investigated antenna 3, proportional to the DN, is supplied to: mixer 5, to the second input of which a signal is output from the output of the GKCH 10, which is a harmonic oscillation with a tunable linearly in the operating frequency range with a period T frequency. The signal from the output of the mixer 5 is fed to the amplifier 6 intermediate frequency. Thus, at that moment of the change in the frequency of the GCCH 1-0, when it differs from the frequency of the signal generator 1 by the intermediate frequency, the signal appears at the output of the intermediate frequency amplifier 6. This is illustrated by the moment t in FIG. 2a The rest of the time there is no signal.

This signal arrives at the peak detector 7, at the output of which a signal is formed that is equal to the maximum signal received at the input into the flow of time T (i.e. at the instant

o 5 0 5

0

0 5 0

five

five

tj, see fig. 26). At the end of each review period (at times t |, tg ..), a synchronization signal is received from the second output of the GKCH 10 to the input of the SEM 8 sample, it is stored here and then recorded in the indicator. 9. At the same time, the synchronization signal is input to the Reset Peak Detector 7 and resets the output voltage to zero. The signal at the peak detector output is shown in FIG. 26

An increase in the dynamic range is achieved by the fact that in the proposed device it is possible to make the pro- band, starting the intermediate frequency amplifier very small, which leads to a decrease in the noise dispersion and, therefore, to an expansion of the lower limit Limiting the dynamic range.

The mutual instability of the frequency-generating units in this case does not lead to a failure of the device’s operability, since it does not matter where t is exactly. You only need to provide itg. This is equivalent to choosing a frequency span more than mutual instability.

Determining the advantage when using the invention as the reduction of the square root of the noise variance relative to the prototype, it is easy to obtain the following expression for it;

P - .

 15h

 where F is mutual frequency instability; . bandwidth signal.

Obviously, the benefit of applying the invention here is at least (J 3, i.e. about 10 dB,

In addition, when using the invention, operation in the frequency band of the intermediate frequency amplifier is always ensured regardless of the frequency departures of the signal generator 1, which is significant. Significantly increases the measurement accuracy.

Claims (1)

Invention Formula A device for measuring the antenna radiation pattern, including a signal generator, connected to the input of the auxiliary antenna, a serially connected mixer, whose input is connected to the output-antenna under study, mounted on 5.6 A rotary bench, and an intermediate frequency amplifier, an indicator characterized in that in order to increase accuracy with a simultaneous expansion of the dynamic range of measurements, a series-connected peak detector is inputted, the input of which is connected to the output amplify S ..z 7388-6 l intermediate frequency, and the sample-storage unit, the output of which is connected to the input of the indicator, the generator of the oscillating frequency, the first output which is connected to the second input, the mixer, and the second output - to the input. Reset the peak detector and to the input of the sample block selection-storage. h