SU1734217A2 - Device for automatic check of radio stations - Google Patents

Abstract

This invention relates to a radio technique. The purpose of the invention is to increase the reliability of the control. The device contains a signal source 1, a receiver 2, a graft antenna 3, a control unit 4, a display unit 5, a differential amplifier 8, a divider 9, three comparators 10, 11, 12, a source 13 of the reference voltage, element 14, element 15, the first and second detectors 16, 17, capacitor 18, low pass filter 19. The radio station is monitored by a device along a coaxial path and a radio path. This makes it possible to increase the reliability of the control. 1 hp f-ly, 3 ill.

Description

The invention relates to a radio communication technique and can be used to automatically control the operability of transmitters of associated radio stations in the course of their operation and is an improvement of the device according to the author.

St. № 1626408.

The purpose of the invention is to increase the reliability of the control.

This goal is achieved by introducing a serially connected receiving antenna, a monitoring receiver and a control unit, the output of which is connected to the second input of the display unit, and the second input is connected to the output of the signal source.

FIG. Figure 1 shows the structural electrical circuit of the device for the automatic control of radio stations; in fig. 2 - block diagram of the control unit; in fig. 3 - logical processing unit, an embodiment.

The device contains a signal source 1, receiver 2, receiving antenna 3, control unit 4, display unit consisting of logic processing unit 6 and display unit 7, differential amplifier 8, divider 9, first, second and third comparators 10, 11,12 , the source 13 of the reference voltage, the element 14, the element OR 15, the first and second detectors 16, 17, the capacitor 18, the low-pass filter 19. In addition, a monitored radio station 20 is shown, consisting of a transmitter 21 and a communication element 22, as well as an antenna 23.

Control unit 4 contains (see Fig. 2) the first and second detectors 24, 25, low-pass filter 26, capacitor 27, differential amplifier 28, resistor 29, three comparators 30, 31, 32, reference voltage source 33, And 34 and the element OR 35.

Block 6 logical processing contains (see Fig. 3) elements HE 36, 37, elements 38-41 and

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The device works as follows

In the initial state, the receiver 2 (see Fig. 1) tunes to the frequency of the monitored radio station 21, while the frequency of tuning the receiver 2 must be no worse than that of the monitored radio station 20, and its high-frequency amplifying path must not have the property of compression in the range of values corresponding to the tolerance zone emitted by the power transmitter 21.

The modulating signal is fed from the output of the source 1 of the signal to the input of the transmitter 21 of the monitored radio station 20. At the same time, the specified signal is fed to the first input of the control unit 4 and the first detector 16. From the output of the transmitter 21, a high-frequency signal is emitted by the antenna 23, and at the same time part of the high-frequency energy zi is fed to the first input of the second comparator 10 and the comparator 30.

The high-frequency signal emitted by the transmitter 21 is received by the receiver 2, from the output of the intermediate frequency amplifier of which is fed to the second input of the control unit 4.

Unit 4 and part of the control device circuit operate as follows (see Fig. 1 and 2).

The signal from the output of the signal source 1 is fed to the first input A of the control unit 4 and the output of the first detector 16 and then to one of the inputs of the comparator 10 and 30, at the other input of which a constant voltage signal is applied from the output of the source 13 (33) reference voltage . By varying the level of this signal, a nominal modulating signal threshold is established at which the given characteristics of the radio station should be ensured in terms of the amplitude modulation coefficient. If the level of the modulating signal at the output of source 1 is higher than the set threshold value, then the inverse output of the comparator 10 (30) contains a logical signal 1; if the level of the modulating signal is below the threshold value, the level of logical O.

A controlled amplitude-modulated signal from the output of the communication element 22 of the monitored radio station 20 for a part of the device circuit or from the output of the intermediate frequency amplifier of the control receiver 2 for the control unit 11 is fed to the input of the envelope detector 16 (24). The envelope detector 16 (24) and the low-frequency filter 19 (26) extract the envelope of this signal. When passing through the capacitor 18 (27), the constant component of the envelope is eliminated. The variable component of the modeling signal is fed to the second 17 (25) detector, the output of which is a constant voltage proportional to the amplitude of the variable component of the modulating signal.

Two signals act on the inputs of the differential amplifier 8 (28): the sum of the constant and variable components of the signal envelope from the output of filter 19 (26) and the variable component of the same signal obtained after passing through the capacitor 18 (27). By applying the first of the signals to the non-inverting input, and the second signal to the inverting input of the differential amplifier 8 (28) at its output, we obtain the difference of these signals, which is proportional to the constant component Vo of the amplitude modulated signal.

From the divider divider 9 (29), the voltage mVo is removed, where m is the proportionality coefficient depending on the position of the slider. This voltage is applied to one of the inputs of the comparator 11 (31), to the other input of which the voltage Vm is supplied from the output of the second detector 17 (25).

At the time when the voltages are equal at the inputs of the comparator 11 (31), the condition mVo Vm or m Vm / Vo is satisfied, which corresponds to the automatic expression for determining the amplitude modulation coefficient. Thus, the gain ratio of divider 9 (29) determines the allowable level of variation of the amplitude modulation coefficient. By changing the coefficient of transfer from 0 to 1 with the help of the resistor slider, it is possible to change the permissible level of change of the amplitude modulation coefficient within 0 ... 100% accordingly.

By reducing the amplitude modulation factor below the set level, a logic 1 signal appears at the output of the second comparator 11 (31), which is fed to one of the inputs of AND 14 (34). If the level of the modulating signal from the output of the source 1 signal is higher than the nominal level, the logical output 1 signal also acts on the inverse output of the first comparator 10 (30). At the inputs of the element And 14 (34) the same The input also contains a signal which, via the OR 15 (35) element, is output to the control unit 4.

If the decrease in the amplitude modulation coefficient is fixed at the moment when the signal level from the output of source 1 is less than the minimum level (for example, in speech pauses), the inverse output of the first comparator 10 (30) will have a logical O signal that blocks the passage of the second comparator signal 11 (31) at the output of the control unit 4, which eliminates the indication of a false failure.

At the same time, the constant-frequency signal Vo of the amplitude-modulated signal, proportional to the carrier level from the output of the differential amplifier 8 (28), is fed to one of the inputs of the third comparator 12 (32), to the other input of which the reference voltage is supplied 13 (33) reference stresses. Setting the level of the specified reference voltage in accordance with the maximum permissible value of the carrier level, it is carried out a tolerance control. When the carrier level drops below the set tolerance, a signal of logical 1 appears at the output of the third comparator 12 (32), which through the OR 15 (35) element arrives at the output of control unit 3.

Thus, the control unit 4 and a part of the device circuit control the carrier level and modulation depth of the high-frequency signal generated by the transmitter 21: a part of the device circuit directly at the transmitter output, and the control unit 4 via the radiated signal.

The signals from the outputs of a part of the device circuit of the control unit 4 are fed to the inputs of the display unit 5, where they undergo logical processing in block 6, the results of which are indicated by the display unit 7.

The b block of logical processing (see FIG. 3), depending on the results of the analysis of monitored signals by the control unit 4, forms at its output one of the signals characterizing possible events observed from the results of the control. In this case, a complete failure of the monitored radio station 20 is recorded only in the presence of signals at their both outputs. The presence of a failure signal only at the output of control unit 4 in the absence of it at the output of a part of the device circuit indicates a deterioration in the quality of the radio channel due to disturbance, propagation conditions, or other similar factors due to

with the propagation medium or caused by the failure of the antenna-feeder path of the monitored radio station 20. Moreover, the absence of signals at the outputs of both parts of the device circuit in control unit 4 indicates a fully operational state of the monitored radio station 20.

The logical processing unit 6 can be implemented in various versions, one of which is shown in FIG. 3, and implements the logical state analysis described above. In the simplest case, the display unit 7 can be implemented as a mnemonic board on which the above-mentioned possible events are displayed according to the results of the control.

Claims (2)

1. Device for automatic control of radio stations by author. St. No. 1626408, characterized in that, in order to increase the reliability of the control, the output of the signal source is connected to the second input of the display unit via the input control unit, in addition, serially connected receiving antenna and receiver, the output of which is connected to the second input of the control unit, are entered into it. 2. Device pop. 1, characterized in that the control unit is made in the form of a series-connected first detector, whose input is the second input of the control unit, a low-pass filter, a capacitor, a second detector, a second comparator, an AND element and an OR element, the output of which is control unit, differential amplifier, the first and second inputs of which are connected to the output of the low-pass filter and the input of the second detector, the first comparator, the first input of which is the first input of the control unit, the output of the first comp The rator is connected to the second input of the And element, the third comparator, the first input and output of which are connected respectively to the output of the differential amplifier and the second input of the OR element, the divider, the corresponding terminals of which are connected respectively to the output of the differential amplifier and the second input of the second comparator, the source of the reference voltage, the first and second outputs of which are connected respectively with the second inputs of the first and third comparators. feJ