SU1725163A1 - Standing-wave and attenuation panoramic meter - Google Patents

Abstract

The meter belongs to the radio measuring technique and can be used to automatically measure the frequency III characteristics of quadrupoles with a large attenuation range and PIC. The meter contains a series-connected oscillating frequency generator 1, a directional coupler 2 of the incident wave, a directional coupler 3 of the reflected wave, a quadrupole 4 under investigation, and a three-digit power divider 5, as well as the first 6 and second 7 detectors connected in series with the microwave amplifier 8 and the fourth detector 9, the third detector 10, the input of which is connected to the second output of the divider 5, the switch 11, the inputs of which are connected to the outputs of the detectors 10, 9, 7, as well as the amplifier 12, the meter 13 of relations and panoramas Ny indicator 14. 2 Il. sl C

Description

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The invention relates to the field of radio metering technology and can be used to automatically measure the frequency characteristics of quadrupoles with a large attenuation range and CWS.

A panoramic CWS and attenuation meter is known, comprising a sweeping frequency generator, a directional incident wave coupler, to the output of the secondary channel of which a first detector is connected, a directional reflector of the reflected wave, to the output of the secondary channel of which the second detector is connected, and the output of the main channel is an input for connecting the test quadripole, the third detector, whose input is the input for connecting the output of the test quadrupole, is a ratio meter, the output of which connected to the input of the panoramic indicator, and the first input to the output of the first detector, the second input to the output of the switch, the inputs of which are connected respectively to the outputs of the second and third detectors and the amplifier whose output is connected to the control input of the oscillating frequency generator, and the input to the output of the first detector .

However, the known meter does not have a high accuracy of measuring large attenuations.

The closest to the technical essence of the present invention is a panoramic meter of CWS and attenuation, comprising a series-connected oscillating frequency generator, a directional incident wave coupler, to the output of the secondary channel of which a first detector is connected, a directional reflector coupler, to the output of the secondary channel which is connected to a second detector and the output of the main channel is the input for the studied quadrupole, the ratio meter, the output of which is connected to the input panoramic indicator, the first input is with the output of the first detector, the second input is with the output of a switch, the inputs of which are connected respectively to the outputs of the second and third detectors, and the amplifier whose output is connected to the control input of the sweeping frequency generator, the amplifier input is connected to the second input of the meter ratios.

However, the meter in question has insufficient accuracy in measuring large attenuations.

The purpose of the invention is to improve the accuracy of measuring large attenuations.

The goal is achieved by connecting in series microwave amplifier and fourth detector, a three decibel power divider, whose input is an input for connecting the output of a four-pole network, the first output is connected to the input of the input microwave amplifier, the second output is connected to a panoramic meter of SWR and attenuation. with

0 input of the third detector, and the output of the fourth detector is connected to the second input of the switch.

When comparing the known device with the invention, we see that the meter in question exhibits new technical properties, expressed in increasing the measurement accuracy of large attenuations, due to the introduction of a fourth amplifier and

0 three-divider power splitter. These properties of the proposed meter are significant, since the measurement of large attenuations with the aid of a known device is accompanied by large measurement errors.

FIG. 1 shows a structural electrical circuit diagram of a panoramic meter of the CWS and attenuations; in fig. 2 - plots of measurement error of large attenuation

0 depending on the attenuation of the studied quadrupole.

The meter contains connected in series oscillator 1 oscillating frequency, directional coupler 2

5 incident wave, directional coupler 3 of the reflected wave, investigated quadrupole 4 and three-digit power divider 5, the first detector 6, the input connected to the secondary output

0 channel tap 2, a second detector 7, an input connected to the output of the secondary channel of the coupling 3, connected in series, a microwave amplifier 8 and a fourth detector 9, a third detector 10, input 5 connected to the second output of the divider 5, switch 11, inputs connected to the outputs detectors 10.9 and 7, respectively, amplifier 12, the output connected to the control input of the generator 1, and the input connected to the output of switch 11, the meter 13 ratios, the first input connected to the output of switch 11, the second input connected output of the first detector 6, panoramic yndika5 torus 14, an input coupled to an output meter 13 relationship.

Switch 11 has three positions.

The meter works as follows.

The attenuation measurement mode is preceded by two calibration modes,

In the first calibration mode, which measures the small and medium attenuation, the output of the coupler 3 is connected to the input of the divider 5. The switch 11 is set to the first position. The DIO signal from the output of the detector 10 is fed through a switch 11 to the first input of the ratio meter 13 and to the input of the amplifier 12. The signal Ue from the output of the detector 6 is fed to the second input of the ratio meter 13. The signal Uis

Ui3 Ki3KioUio / U6

from the output, the relationship meter 13 is applied to a panoramic indicator 14, where Kis is a scale factor having a voltage uniformity; Kyu - channel gain factor divisible meter 13 relations.

The operator, by adjusting Kyu, achieves on a scale of the indicator 14 for setting a single voltage level LHa at the output of the meter 13 ratios. Moreover, Kyu is UtcrUe and, therefore,.

Coefficient value

Kio U6 / Uio

remains unchanged for the measurement period of small and medium attenuation.

In the second calibration mode, providing a measurement of large attenuations, between the output of the main channel of the coupler 3 and the input of the divider 5, a quadrupole is turned on with a known value of the AE transfer coefficient module. The switch 11 is set to the second position. The signal Ug from the output of the detector 9 is fed through a switch 11 to the first input of the ratio meter 13 and to the input of the amplifier 12. The signal Ue from the output of the detector 6 is fed to the second output of the ratio meter 13. 1Нз signal

Ul3 Kl3K9U9 / Ue Kl3K9UloA3T./Ue

from the output of the meter 13 relations goes to the panoramic indicator 14, where Kg is the gain of the channel of the divisible meter 13 relations.

The operator, by adjusting Kg, achieves on the scale of the indicator 14 for setting a single voltage level 1 M3 at the output of the meter 13 ratios. With this and, therefore,. Coefficient value

Kg U6 / U9 U6 / (UioA3T)

(2)

remains unchanged for the period of measurement of large attenuations.

The CWS measurement mode is preceded by

Calibration mode, when a shorting connector is connected to the output of the main channel of the coupler 3. The switch 11 is set to the third position. The signal U from the output of the detector 7 is fed to the first input of the meter 13 ratios. The signal Ue from the output of the detector 6 is fed to the second input of the ratio meter 13. The signal Ui3 KisK7U7 / U6 from the output of the meter 13 ratios is supplied to the indicator 14, where the gain of the channel of the dividend meter 13 ratios.

The operator, by adjusting K, achieves on the scale of the indicator 14 for setting a single voltage level 1 M3 at the output of the meter 13 ratios. At the same time KyU7 Ue and, therefore,. Coefficient value

25

K7 U6 / U7

remains unchanged for the CWS measurement period. This completes the calibration.

30 In the mode of measuring small and medium attenuation between the output of the main channel of the coupler 3 and the input of the power divider 5, the quadrupole under study 4 is switched on. The switch 11 is set to the first position.

With the weakening of the investigated quadrupole 4, equal to the minimum, the working point of the third detector 10 is located on the upper boundary of the quadratic segment,

40a is the operating point of the first detector 6 at the lower boundary of the quadratic region.

With increasing attenuation, the operating point of the detector 10 moves to the lower boundary of the quadratic portion. With average

45 the weakening of the quadrupole 4 working point of the detector 10 reaches the lower limit. The signal from the output of amplifier 12 at the output of generator 1 establishes a signal at which the operating points of the detectors

50 3 and 10 are set to the upper boundary of the quadratic region.

The output signal Uioc of the detector 10 is supplied via switch 11 to the first input of the meter 13 ratios. Signal ue with

55 of the output of the detector 6 is supplied to the second input of the meter 13 ratios. The 1Нз signal, taking into account the calibration condition (1), has the form

,

(3)

where Ah - the module of the transfer ratio of the quadrupole 4.

The value of Ax is measured on a scale of indicator 14.

In the mode of measuring large attenuations, the quadrupole 4 remains in its place, and the switch 11 is set to the second position.

With increasing attenuation of the quadrupole 4, the operating point of the detector 9 moves to the lower boundary of the quadratic region and reaches it with maximum attenuation.

The signal Ug from the output of the detector 9 is supplied through a switch 11 to the first input of the meter 13 ratios. The signal Ue from the output of the detector 6 is fed to the second input of the meter 13 ratios. Taking into account the calibration conditions (2), the signal at its output is

Ui3 Ui3 Ax / A3T.

The value of Ax is measured on a scale of indicator 14.

In the measurement mode, the SWR switch 11 is set to the third position and the meter operates as described above. The signal U from the output of the detector 7 through the switch 11 is fed to the first input of the ratio meter 13, the signal Ue is fed to its second input. Taking into account the calibration conditions (3), the signal at the output of the meter 13 relations is

,

where Гх is the modulus of the reflection coefficient from the input of the investigated quadrupole 4.

The value of the CWS is measured on the scale of the indicator 14.

From formula (4), are found for Ax

 Olg (U 13 / U 13) +1 01 dAet. (five)

Analysis of expression (5) shows that with the introduction of new elements and connections into the meter, the range of measured attenuations increases by the amount of attenuation of the reference quadrupole.

In order to reveal the effect of increasing the accuracy in the proposed meter, it is compared with the known one.

Gauges of group P2 (see technical description, for example, on meter P2-65) measure attenuation up to 30 dB with an error determined by the formula

d 0.05 AH + 0.35.

(6)

The measurement of attenuation above 30 dB is impossible, since the measured signal is commensurate with the noise level of the microwave detector and the measurement error becomes unacceptable.

Taking into account the expression (5) for the error of the proposed meter can be written

d, 05 (Ah-Aet) + 0.35.

()

The graphs of the dependences of the error 15 5d on the magnitude of the measured attenuation, calculated by formulas (6) and (7), are shown in FIG. 2, from which it follows that the introduction of new elements and connections into the meter makes it possible to increase the accuracy of measurements of large attenuations, and this achieves the goal.

From formulas (6) and (7), it follows that with the same measurement error 5d (for example, (5d 1.85 dB), the known meter measures attenuation Ax 30 dB, and the proposed Ax 55 dB. This increases the efficiency instrumentation.

Claims (1)

30 Formula of Invention A panoramic meter of the standing wave and attenuation coefficient, which contains a series of oscillating frequency generator connected in series, a directional response of the incident wave, to the output of the secondary channel of which a first detector is connected, a directional coupler of the reflected wave, to the output of the secondary channel of which the second detector is connected 40, the output of the main channel is an input for connecting the input of a quadrupole under study, as well as a third detector, a switch, inputs connected to the outputs of the second and third detector, 45 of the ratio meter, the first input connected to the output of the switch, and the second input to the output of the first detector connected to the first input of the ratio meter, and the output connected to the control input of the oscillating frequency generator, a panoramic indicator connected to the output of the ratio meter, from that then, in order to increase the measuring accuracy of large 55 attenuations, a microwave amplifier and a fourth detector connected in series are introduced into it, as well as a power divider whose input is an input for connecting the output of a quadrupole under study, the first output is connected to the input Microwave amplifier, the second output is connected to the input of the third detector, and the output the fourth detector is connected to the second input of the switch. 20 21 22 23 24 25 26 27 28 29 30 Adb FIG. 2