SU1345141A1 - Electric field intensity automatic meter - Google Patents

Abstract

The invention relates to a radio measuring technique. The purpose of the invention is to increase the speed. The measurer contains antenna 1, switches 2 and 5, radio receiver unit 3, amplitude detector 4, integrated circuits (IC) 6 and 7, comparator 8, gr 9, controlled attenuator (UA) 10 and control unit (CU) 11 The radio signal received by the antenna 1 and the voltage from the UA 10 are alternately switched. amplified and detected. Then, the detected voltages are synchronously switched by the switch 5: to the inputs of the comparator 8, at the first input of which the voltage is directly proportional to the voltage of the electromagnetic field received by the antenna 1, and at the second input to the voltage at the output of UA 10. At the comparator 8, the input the voltages are compared in amplitude, and the voltage is the reference voltage of g. 9. According to the results of the comparison, the VL 10 is adjusted, the values of which measure the intensity of the electromagnetic field by taking into account the efficiency of us 1 at the operating frequency. The goal is achieved by introducing switch 5 and IC 6 and 7, which convert the pulsed form of voltages from the outputs of switch 5 to analog to allow the use of a conventional analog comparator 8. Examples are given of G 9, UA 10 and BU 11. 1 sludge. s (L 00 4 SP

Description

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The invention relates to radio metering. technique and can be used to measure stress. electromagnetic field, radiation patterns of various antennas, etc.

The purpose of the invention is to increase speed.

The drawing shows the structural electrical circuit of the automatic meter of electromagnetic field intensity.

Automatic electromagnetic field meter contains antenna 1, first switch 2, radio receiving unit 3, amplitude detector 4, second switch 5, first 6 and second 7 integrating circuits, comparator 8, generator 9, controlled attenuator 10, control unit 11. The generator 9 consists of an intermediate frequency generator 12 and a mixer 13, the controlled attenuator 10 consists of a controlled limiter 14, a block 15 of constant attenuators. The control unit 11 consists of a 16 clock pulse generator, a frequency divider 17, an AND 18 block, a first pulse counter 19, a digital-to-analog converter 20, a single-oscillator 21, a second pulse counter 22, a decoder 23.

Automatic meter of electromagnetic field intensity works as follows.

The clock pulse generator 16 generates pulses, which at the first output of the control unit 11 are fed to the control inputs of the first .-. 2 and second 5 switches and a frequency divider 17, in which the pulses are divided by frequency and are fed to the first input of the block 18. As in the initial state at the output of the comparator 8, the unit voltage level is, the pulses from the output frequency divider 17 is passed to the first input of the first counter 19, which counts them. A binary code is generated at the output of the first counter 19, which is converted by the digital-to-analog converter 20 to the corresponding voltage, i.e. Each binary code at the output of the first counter 19 corresponds to a certain voltage at the output of the digital-to-analog converter 20, which at the second output of the control unit 11 is fed to the first input of the generator 9.

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The aperture with the frequency of the local oscillator from the second output of the radio receiving unit 3 is fed to the input of the generator 9, to the second input of the mixer 13, where it mixes with the voltage produced by the intermediate frequency generator 12, whose frequency is stabilized and equal to the intermediate frequency of the receiving radio 3, and at the output the mixer 13 receives the voltage with the frequency to which the radio receiver unit 3 is tuned. This voltage is limited in amplitude by the controlled limiter 14, to the control input of which by the first input of the generator 9 n It supplies the control voltage from the output of the digital-to-analog converter 20 of the control unit 11: neither, and its output produces a voltage with a frequency to which the radio receiver unit 3 is tuned with fixed and precisely known amplitude values specified by the control unit 11. The output voltage of the controlled limiter 14 is fed to the output of the controlled attenuator 10

An antenna 1 receives the radio signal and the voltage from the output of the controlled attenuator 10 is alternately switched at the input of the radio receiver unit 3 by the first switch 2. The radio receiver unit 3 amplifies alternately switched input voltages, which then flow to the detector 4, where. detected. From the detector output 4, the detected voltages are switched to the inputs of the comparator 8 by the second switch 5 synchronously with the first pulses fed to their control inputs from the first output of the control unit 11. At the same time, at the first input of the comparator 8, the voltage is directly proportional to ... the intensity of the electromagnetic field received by antenna 1, and at the second input is the voltage at the output of the controlled attenuator 10. In the comparator 8, the input voltages are compared the voltage from the output of the generator 9.

The first and second 6 and 7 integrating circuits convert the pulsed form of voltages from the outputs of the second switch 5 into an analog circuit for being able to use a conventional analog comparator as comparator 8.

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As the voltage at the output of the digital-to-analog converter 20 increases and, accordingly, the output of the controlled attenuator 10 in the comparator 8 compares the input voltages and, if the equality does not occur before the first counter 19 is completely filled, the pulse from its second output switches the second counter 22, which has changed the binary code at the output of which is decrypted by the decoder 23, and the third output of the control block 11 switches attenuators in the block 15 of fixed attenuators to an attenuator with a smaller attenuation coefficient, and - switching input attenuators radio receiving unit 3 on a larger attenuation coefficient due to its overload Bezhanov input voltages. In this case, the first counter 19 starts counting input pulses from a zero binary code state at its output. The process of switching permanent attenuators in the block 15 of permanent attenuators and in the radio receiver 3 and rebuilding the controlled attenuator 10 occurs until the inputs of the comparator 8 are matched by voltage amplitude directly proportional to the received antenna 1 voltage. The electromagnetic field and the output voltage of the generator 9. In this case, the comparator 8 changes its state at the output, which, entering the input of the control unit 11, blocks the passage through the AND 18 unit of pulses from the output of the frequency divider 17 to the first input of the first counter 19 and starts the one-shot 21.

The output voltage of the controlled attenuator 10, expressed and recorded in binary code in the first counter 19, is fed from its output on the output of the control unit 11 to the third input of the display and matching unit 24, the value of the measuring range expressed and recorded in two - the identical code in the second counter 22, is fed from its output on the fourth output of the control unit 1t to the second input of the display and matching unit 24. The resolution pulse, which is the output pulse of the one-shot 21, is fed through the sixth output of the control unit 11 to the fourth output of the device. Voltage with frequency hetero1

Dina radio receiving unit 3 is supplied from its second output to the first output of the device,

For information processing, a computer can be used, the inputs of which to the fourth are connected to the outputs of the device. In this case, the values of the output voltage of the controlled attenuator 10 and the measurement range received at its first and fourth inputs are processed to bring them to the value of the measured electromagnetic field strength by taking into account the antenna efficiency at the operating frequency (the local oscillator frequency is measured in control unit 24 and agreement). The measured intensity of the electromagnetic field is recorded in the computer memory and at the same time can be displayed on its display. In addition, if location sensors (apparatus) are connected to the computer's (additional) input, for example, radio navigation system equipment, which determines the distance and azimuth of the aircraft to the aircraft, the coordinates of which are known, then simultaneously with the measured value field strengths are recorded in the memory of the coordinate values where the measurements were taken. Thus, the accumulation of measurement results can be made and, when a printing device or a plotter device is connected to the output of the computer, the results can be printed or drawn (for example, in the form of radiation patterns).

At the end of the one-shot 21 pulse, its first front and second 22 counters are reset to zero, while the voltage from the output of the digital-to-analog converter 20 becomes such that the output voltage of the controlled limiter 14 becomes maximum, the attenuator 15 is switched on in the block 15 constant attenuator with maximum attenuation, and in the radio receiver unit 3, the input attenuators are turned off to provide maximum gain. The comparator 8 returns to the initial (single) state, thereby allowing the passage of pulses from the output of the frequency divider 17 to the first input of the first counter 19, thereby starting a new measurement cycle.

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Claims (1)

Claims of the invention An automatic meter, for example, of the electromagnetic field, comprising an antenna connected to the first input of the first switch, the output of which is connected to the first input; the radio receiver unit, the input of the radio receiver unit is connected to the first output of the control unit and the first controllable input of the controlled attenuator, the second output of the control unit is connected to the control input of the first switch, the first input of the control unit is connected to the outputs of the comparator, the first output of the radio receiver the unit is connected to the input of the amplitude detector, and the second output of the receiving unit is connected to the generator input, characterized in that, in order to improve speed, a second switch is introduced, the input The first and second integrating circuits connected respectively between the first and second outputs of the second switch and the first and second inputs of the comparator, the control input of the second switch are connected to the second output of the control unit, the controlled attenuator is made as serially connected controlled limiter and a block of constant attenuators, the control input of which is the first the control input of the controlled attenuator, and the output of the output of the controlled attenuator, the input and control , Q 5 0 5 o five sixteen the input of the controlled limiter is respectively the input and the second control input of the controlled attenuator, the control unit is made in the form of serially connected clock generator, frequency divider, AND block, first pulse counter, second pulse counter and decoder, single-oscillator and digital-analogue a converter, the input of which is connected to the output of the first pulse counter, and the output of the one-shot is connected to the reset inputs of the first and second pulse counters, while the decoder outputs, pulse generator and digital-analog converter are respectively the first, second and third outputs of the control unit, the inputs of the And block and the one-shot are combined and are the input of the control unit, the third output of the control unit is connected to the second control input of the controlled attenuator, the input of which is connected to the output of the generator , which is made in the form of series-connected intermediate frequency generator, equal to the intermediate frequency of the receiving unit, and the mixer, the second input of which is the input of the generator and the output of the generator, the second output of the receiving unit, the outputs of the first and second pulse counters and the output of the one-shot are respectively the first, second, third and fourth outputs of the device.