SU1177922A1 - Device for measuring blocking band of radio receiver - Google Patents

Abstract

A DEVICE FOR MEASURING THE BLOCKS OF RADIO RECEIVERS, containing a serially connected useful signal generator, a matching unit and a radio receiver under study, an interfering signal generator, the first output of which is connected to the second input of the matching unit, a serially connected reference source and amplitude comparator, as well as a bend detector and a detector. block, characterized in that, in order to improve device speed and accuracy of measurement of the blocking band of the radio receiver key, servo drive, standby multivibrator, first, second and third elements OR, first and second inverters, first and second differentiation units, RS flip-flop, frequency meter, calculator and starting pulse shaper, with a radio receiver connected to the input the envelope detector, the first and second inputs of the key are connected respectively to the outputs of the radio receiver and the envelope detector, and the output is connected to the second input of the amplitude comparator, the first differentiation unit is connected in series, the input The first inverter, the first element OR, the second input of which is connected to the output of the first inverter, the waiting multivibrator, the second differentiation unit and the second inverter, are connected in series to the output of the amplitude comparator, the first and second inputs of which are connected respectively to the outputs of the interfering signal generator and standby multivibrator, and the calculator, the first and second control inputs of which are connected respectively to the output of the first OR element and the second (L output of the noise generator the second signal, the first, second and third inputs of which are connected respectively to the outputs of the first differentiation unit, the first inverter and the second output of the interfering generator, the RS trigger and servo drive, whose output mechanically connected to the tuning mechanism of the generator of the interfering signal, and also sequentially connected to the driver N5 of the start pulse and the third element OR, the second input of which is connected to the output second inverter, and an output coupled to the S-input of RS-latch.

Description

The invention relates to a radio metering technique and can be used to automatically measure and record the blocking band of radio receivers.

The purpose of the invention is to improve the device speed and accuracy of measurement of the blocking band of radio receivers by automatically measuring the lower and upper frequencies of the blocking band of radio receivers.

FIG. Figure 1 shows the structural electrical circuit of the device proposed; in fig. 2 - timing diagrams for the operation of the device.

The device for measuring the blocking band of the radio receivers includes a signal generator 1, a matching unit 2, a radio receiver 3 under study, an envelope detector 4, a key 5, an amplitude comparator 6, a reference voltage source 7, a servo drive 8, an interfering signal generator 9, a standby multivibrator 10, the first 11.1 , the second 11.2 and the third 11.3 elements OR, the first G2.1 and the second 12.2 inverters, the first

13.1 and second 13.2 differentiation units, RS flip-flop 14, frequency meter 15, calculator 16, start pulse generator 17, recorder 18, while calculator 16 contains serially connected switch 19, whose input and control input are respectively input and first control the input of the calculator 16, the first storage unit 20.1, the second storage unit 20.2, the input of which is connected to the second output of the switch 19, and the output connected to the second input of the digital subtraction unit 21, the delay line 22, the output of which is connected to the control mi inputs of the first 20.1 and second

20.2 memory blocks, and a digital frequency code generator 23 of the useful signal, the output of which is connected to the second input of the digital dividing device 24, whose control input combined with the input of the delay line 22 is the second control input of the calculator 16, while the generator 1 outputs signal and generator 9 of the interfering signal through the matching unit 2 are connected to the input of the studied radio receiver 3, the output of which is connected to the inputs of the key 5 and the envelope detector 4, the output of the latter is connected to the control input to Key 5, the source 7 of the reference signal, the amplitude comparator 6, the output of the key 5 is connected to another input, the first differentiation unit 13.1, the output of which is also connected to the input of the first inverter 12.1, the first element OR 11.1 to the second input of which the output of the first inverter is connected 12.1, the waiting multivibrator 10, the second differentiation unit 13.2 and the second inverter 12.2,

Frequency meter 15 is connected in series, the input and control input of which are connected respectively to the outputs of the generator 9 of the interfering signal and the standby multivibrator 10, and the calculator 16, the first and second control inputs of which are connected respectively to the output of the first element OR 11.1 and the second output of the interfering signal generator 9 and the output is connected to the input of the recorder 18, the second element OR 11.2 is connected in series, the first, second and third inputs of which are connected respectively to the outputs of the first block 13.1 of differentiation neither the first inverter 12.1 and the second output of the generator 9 of the interfering signal, the RS flip-flop 14 and the servo drive 8, the output of which is mechanically connected to the tuning mechanism of the generator 9 of the interfering signal in frequency, as well as the starting pulse driver 17 and the third element

OR 11.3, the second input of which is connected to the output of the second inverter 12.2, and the output is connected to the S-input of the RS flip-flop 14.

The proposed device operates as follows.

A useful unmodulated signal from the output of the generator 1 and an interfering amplitude-modulated signal from the output of the generator 9 through the matching unit 2 is fed to the input of the studied radio receiver 3. The frequency of the generator 9 is set to the bottom

SRI limit of measurement range f with the output signal level X ,, y, .. permissible for the input circuits of the radio receiver 3. The frequency of the generator 1 signal is set to the frequency of the main reception channel fo. With the output signal level .., .. equal to the sensitivity of the radio receiver 3 which generates at its output a signal YQ. (Fig. 2a), which is further compared in amplitude comparator 6 with a predetermined constant voltage y0 (Fig. 2a) corresponding to the output voltage of the studied radio receiver 3 with an acceptable value of its blocking factor vani.

At the initial time moment t О RS, the trigger 14 is in the initial state "O. In this case, at its output, the voltage U corresponds to a logical "O (Fig. 26). The starting pulse generator 17, via the third element OR 11.3, supplies the S input of the RS flip-flop 14, the voltage Uj, which sets it to position 1, which by means of the servo drive 8 performs a smooth change of the frequency of the interfering generator 9 in the measured frequency range ff.

Decreasing the output voltage YO,. the radio receiver 3 to the value Y (Fig. 2a, ti ti) at the output of the amplitude comparator 6 results in a voltage jump Uj (Fig. 20, .t ta), which is differentiated by the first differentiation unit 13.1. At the output of block 13.1, a positive pulse Y is produced (Fig. 2d, t - 1-d) which, through the second element OR 11.2, goes to the R input of the RS flip-flop 14 and transfers it to the initial state "O." At the output of the RS flip-flop 14, the voltage C becomes the corresponding 1, the logical "O" (Fig. 26, t t,) and the frequency tuning of the signal of the generator 9 by the servo-drive 8 stops. At the same time, the pulse U through the first element OR 11.1 starts the waiting multivibrator 10 (Fig. 2d, tt) and using the switch 19 the calculator 16 connects the output of the frequency meter 15 to the input of the first storage unit 20.1 of the calculator 16. The voltage Uj of the pulse of the waiting multivibrator 10 turns on the frequency meter 15 ( through the built-in relay in the diagram (not shown), measuring the value of the lower frequency 1 - the blocking band of the radio receiver 3, which is stored in the digital code by the block 20.1 of the calculator 16.

The duration f of the pulse of the waiting multivibrator 10 is selected on the basis of the time required to measure and memorize the frequency n. At the moment of termination of the pulse of the waiting multivibrator 10, the frequency meter 15 is turned off. The falling edge of the pulse Ug of the standby multivibrator 10 is differentiated by the second differentiation unit 13.2. At the output of the latter, a negative pulse U (Fig. 2e, 1 1z) is produced, which is inverted by the second inverter 12.2. The output of the inverter 12.2 produces a positive pulse UT (Fig. 2g, t tj), which through the third element OR 11.3 goes to the S input of the RS flip-flop 14. The output of the latter produces a voltage Ui corresponding to the logical "1" (Fig. 26, t tj), which with the help of servo drive 8 performs a further frequency tuning of the generator 9 signal.

When the frequency of the generator 9 of the interfering signal enters the bandwidth of the side or main reception channels of the radio receiver 3 at the output of the envelope detector 4, the voltage U is generated, the envelope of the modulated signal of the generator 9, which closes the electronic switch 5, and the voltage from the output of the amplitude comparator 6 does not arrive. When the upper frequency f of the blocking band by the generator 9 of the interfering signal, at which the amplitude of the output signal of the radio receiver 3 increases up to YO (FIG. 2a, t tj.), The output of the amplitude comparator 6 again produces a voltage jump Uj (FIG. 26, t 14), which differentiates with the first differentiation unit 13.1. At the output of block 13.1, a negative pulse is generated and (fig. 2d, 1t).

which is inverted by the first inverter 2.1. At the output of the latter, a positive pulse LJg is produced (fig. 2z, 1 14-), which through the second element OR 11.2 enters the R input of the RS flip-flop 14. The RS flip-flop 14 returns to its initial state "O," (Fig. 26, tt) and the frequency tuning of the interference signal generator 9 by the servo drive 8 is stopped. Simultaneously, the pulse of ultrasound through the first element OR

11.1 starts the waiting multivibrator 10 (Fig. 2d. T 1) NS using the switch 19 calculator 16 connects the output of the frequency meter 15 to the input of the second storage unit 20.2 of the calculator 16. The voltage Uj of the pulse of the waiting multivibrator 10 turns on the frequency meter 15, measuring the upper frequency f of the blocking band radio receiver 3, which is stored in the digital code by block 20.2 of the calculator 16. At the time of termination of the pulse of the waiting multivibrator 10, the frequency meter 15 is turned off. The falling edge of the pulse of the waiting multivibrator 10 is differentiated by the second differentiation unit 13.2. At the output of block 13.2, a negative pulse Ug is produced (Fig. 2e, t 15), which is inverted by a second inverter

12.2 (Fig. 2g, t ts) through the third element OR 11.3 goes to the S input of the Trigger 14. The output of the latter produces a voltage U, (Fig. 26, 1 j tj): which with the help of a servo drive 8 performs a further adjustment the frequency of the signal generator 9. At the same time, at the output of the digital subtractor 21, the calculator 16 produces a digital code corresponding to the frequency difference fg-1, which is fed to the first input of the digital dividing device 24 of the transmitter 16, to the second input of which is fed from the generator 23 of the digital frequency code useful si drove a digital code corresponding to the frequency settings of the generator 1.

When the tuning frequency of the generator 9 reaches the upper frequency f of the measurement range from the second output (limit switch) of the interference signal generator 9 to the third input of the second element OR 11.2 and the second control input of the calculator 16, a voltage is applied. In this case, the RS flip-flop 14 returns to the initial state "O (Fig. 26 t tj.)" And the frequency tuning of the signal of the generator 9 by the servo-drive 8 stops. At the same time, the voltage Tso arrives at the control input of the digital dividing device 24 of the calculator 16, making it turn on. The digital dividing device 24 is triggered and the result

dividing recorded

tch.m device. The pulse delay 1 by the element 22 of the calculator 16 is selected on the basis of the time required for registering the obtained value of the result of the division. After this time expires, the delayed impulse Uio enters the control inputs of the first 20.1 and second 20.2 storage blocks of the calculator 16, returning

they are in the initial state; those, and in this process the measurement of the blocking band of the radio receiver 3 is stopped.

The proposed device, in comparison with the known, allows to improve the speed and accuracy of measurement, as well as the accuracy of recording the value of the blocking band of radio receivers.

3

Fig. / NofovHb / a (primary) receiving channels

to

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t ,. t.

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one

FIG. 2 and ts

Claims (1)

A DEVICE FOR MEASURING A RADIO LOCKING BAND, containing a useful signal generator, a matching unit and a studied radio receiver, an interfering signal generator, the first output of which is connected to a second input of a matching unit, a reference voltage source and an amplitude comparator, as well as an envelope detector and a recording unit , characterized in that, in order to improve the speed of the device and the accuracy of the measurement of the blocking band of the radios, in a key, a servo drive, a waiting multivibrator, the first, second and third elements of OR, the first and second inverters, the first and second differentiation units, the RS-trigger, the frequency meter, the calculator and the driver of the start pulse are introduced, while the output of the radio receiver is connected to the input of the envelope detector, the first and second inputs of the key are connected respectively to the outputs of the radio receiver and envelope detector, and the output is connected to the second input of the amplitude comparator, the first differentiation unit is connected in series, the input of which is connected n to the output of the amplitude comparator, the first inverter, the first OR element, the second input of which is connected to the output of the first inverter, the waiting multivibrator, the second differentiation unit and the second inverter, a frequency meter is connected in series, the first and second inputs of which are connected respectively to the outputs of the interfering signal generator and the standby multivibrator, and a calculator, the first and second control inputs of which are connected respectively § with the output of the first OR element and the second output of the interfering signal generator, and in the output is connected to the input of the recording unit, the second OR element is connected in series, the first, second and third inputs of which are connected respectively to the outputs of the first differentiation unit, the first inverter and to the second output of the jamming signal generator, RS-trigger and servo drive, the output of which is mechanically connected to the mechanism adjustment of the interfering signal generator, as well as a trigger pulse shaper and a third OR element, the second input of which is connected to the output of the second inverter, and the output are connected in series connected to the S-bhodom of the RS-trigger. SU. „, 1177922