RU2357363C1 - Device for controlling operation of radio station with pseudorandom operational frequency readjustment - Google Patents

Abstract

FIELD: radio engineering.

SUBSTANCE: present invention relates to radio engineering and can be used for detecting broadcast of a radio station with pseudorandom operational frequency readjustment, their direction finding and determining the frequency spectrum used. The device for controlling operation of a radio station with pseudorandom operational frequency readjustment contains a first receiving antenna, second receiving antenna, made in form of a vibrator and frame antenna, a unit for controlling directional pattern, two memory blocks, frequency metre, three radio paths, four amplitude detectors, a heterodyne, a saw-tooth voltage generator, stopping pulse former, threshold block, dividing circuit, commutator, observation oscilloscope, three narrow-band filters, six phase inverters, nine adders, four band-pass filters, two 90° phase shifters, seven keys, time interval measuring device, comparator unit, input device, phase detector, unit for generating control voltage, motor, platform, reduction gear and an angle indicator.

EFFECT: more functional capabilities through controlling operation of mobile radio stations with pseudorandom operational frequency readjustment.

6 dwg

Description

The proposed device relates to the field of radio engineering and can be used to detect the broadcasting of radio stations with pseudo-random tuning of the operating frequency (PFRCH), their direction finding and determining the grid of used frequencies.

Known devices for monitoring the operation of radio stations with pseudo-random tuning of the operating frequency (ed. Certificate of the USSR No. 403084, 1742741, 1710471; RF patents No. 2161863, 2231926, 2275744; US patents No. 5379046, 6018651; patent WO No. 96/19877; Foreign Radio Electronics, Moscow: Sov. Radio, 1979, No. 3, P. 42-51, Fig. 5 and others).

Of the known devices, the closest to the proposed one is “A device for monitoring the operation of radio stations with pseudo-random tuning of the operating frequency” (RF patent No. 2275744, НВВ 17/00, 2004), which was chosen as a prototype.

The specified device provides for the detection of weak short-term signals in the loaded frequency ranges and the assessment of their frequency against the background of a large number of powerful masking interference.

In addition, the known device provides increased selectivity and noise immunity of the panoramic receiver-direction finder, and also eliminates the ambiguity in determining the grid of frequencies used. This is achieved by suppressing false signals (interference) received via mirror, Raman and intermodulation channels, using the phase-compensation method and the narrow-band filtering method.

An object of the invention is to expand the functionality of the device by monitoring the operation of mobile radios with pseudo-random tuning of the operating frequency.

The problem is solved in that a device for monitoring the operation of radio stations with pseudo-random tuning of the operating frequency, containing, in accordance with the closest analogue, a series-connected first receiving antenna, a first narrow-band filter, a first phase inverter, a first adder, the second input of which is connected to the output of the first receiving antenna , the first bandpass filter, the second phase inverter, the second adder, the second input of which is connected to the output of the first adder, the second bandpass filter, the second phase inverter, the second su a matrator, the second input of which is connected to the output of the first adder, a second bandpass filter, the third phase inverter, the third adder, the second input of which is connected to the output of the second adder, the first radio path, the second input of which is connected to the first output of the local oscillator, the fourth adder, the first multiplier, the second input which is connected to the output of the third adder, the second narrow-band filter, the third amplitude detector, the first key, the second input of which is connected to the output of the fourth adder, the first amplitude detector, the circuit is divided ia, the second input of which is connected to the output of the second amplitude detector, a threshold block, a stop pulse shaper, a sawtooth voltage generator, and horizontally-deflecting plates of an oscillographic indicator connected in series to the output of a sawtooth voltage generator local oscillator, the first phase shifter 90 °, the third radio path, the second the input of which is connected to the output of the third adder, and the second 90 ° phase shifter, the output of which is connected to the second input of the fourth adder, is sequentially turned on the third narrow-band filter, the fourth phase inverter, the fifth adder, the third bandpass filter, the fifth phase inverter, the sixth adder, the second input of which is connected to the output of the fifth adder, the fourth bandpass filter, the sixth phase inverter, the seventh adder, the second input of which is connected to the output of the sixth adder, the second radio path, the second input of which is connected to the first output of the local oscillator, the eighth adder, the second multiplier, the second input of which is connected to the output of the seventh adder, the fourth narrow-band filter, the fourth a a stove detector, a second key, the second input of which is connected to the output of the eighth adder, a second amplitude detector, a switch, the second, third and fourth inputs of which are connected to the outputs of the first amplitude detector, stop pulse former and division circuit, respectively, connected in series to the seventh adder fourth radio path, the second input of which is connected to the output of the first phase shifter by 90 °, and the third phase shifter by 90 °, the output of which is connected to the second input of the eighth adder, after A frequency meter is connected to the second output of the first radio path, the second input of which is connected to the output of the stop pulse generator, the fourth key, the second input of which is connected to the output of the comparison unit, and the first memory block, the second input of which is connected to the output of the stop pulse generator, connected in series to the output the first amplitude detector, the third key, the second input of which is connected to the output of the stop pulse shaper, a time interval meter, a second memory unit, the second input to of which is connected to the output of the input device, the comparison unit, the second and third inputs of which are connected to the outputs of the frequency meter and time meter, respectively, and the fifth key, the second input of which is connected to the output of the time interval meter, and the output is connected to the third input of the first memory unit, vertically - the deflecting plates of the oscillographic indicator through the sixth key are connected to the outputs of the switch and the comparison unit, the second receiving antenna and the radiation pattern control unit are different from bl the best analogue in that it is equipped with a ninth adder, a seventh key, a phase detector, an angle indicator, a platform and a gear, the second receiving antenna made in the form of an antenna system consisting of a vibrator and a loop antenna placed on the platform and connected through the ninth adder to the inputs the third narrow-band filter and the fifth adder, the radiation pattern control unit is made in the form of series-connected control voltage generation unit and a motor connected through a gearbox to the boards form. The reducer is equipped with an angle indicator, the seventh key is connected to the output of the first key, the second input of which is connected to the output of the stop pulse shaper, and the phase detector, the second input of which is connected to the output of the second key, and the output is connected to the input of the control voltage generating unit.

The structural diagram of the proposed device is presented in figure 1. A frequency diagram explaining the process of forming additional receiving channels is shown in FIG. Examples of intermodulation interference are shown in FIGS. 3 and 4. The radiation patterns of receiving antennas 1 and 2 are shown in FIG.

The relative position of the vibrator 2.1 and the loop antenna 2.2 is shown in Fig.6, a side view is Fig.6, and a bottom view of the cross section is Fig.6, b.

The device comprises series-connected the first receiving antenna 1, the first narrow-band filter 15.1, the first phase inverter 16.1, the first adder 17.1, the second input of which is connected to the output of the receiving antenna 1, the first bandpass filter 18.1, the second phase inverter 16.2, the second adder 17.2, the second input of which is connected to the output of the adder 17.1, the second bandpass filter 18.2, the third bass reflex 16.3, the third adder 17.3, the second input of which is connected to the output of the adder 17.2, the first radio path 6.1, the second input of which is connected to the first output of the local oscillator 8, even the fifth adder 17.4, the first multiplier 20.1, the second input of which is connected to the output of the adder 17.3, the second narrow-band filter 15.2, the third amplitude detector 7.3, the first key 21.1, the second input of which is connected to the output of the adder 17.4, the first amplitude detector 7.1, division circuit 12, the second the input of which is connected to the output of the second amplitude detector 7.2, the threshold block 11, the stop pulse generator 10 and the sawtooth voltage generator 9, the output of which is connected to the input of the local oscillator 8, connected in series to the second output of the gete homeland 8, the first phase shifter 19.1 by 90 °, the third radio path 6.3, the second input of which is connected to the output of the adder 17.3, and the second phase shifter 19.2 by 90 °, the output of which is connected to the second input of the adder 17.4, the third narrow-band filter 15.3 connected in series, the fourth phase inverter 16.4, the fifth adder 17.5, the third bandpass filter 18.3, the fifth phase inverter 16.5, the sixth adder 17.6, the second input of which is connected to the output of the adder 17.5, the fourth bandpass filter 18.4, the sixth phase inverter 16.6, the seventh adder 17.7, the second input of which is connected to the output m of the adder 17.6, the second radio path 6.2, the second input of which is connected to the first output of the local oscillator 8, the eighth adder 17.8, the second multiplier 20.2, the second input of which is connected to the output of the adder 17.7, the fourth narrow-band filter 15.4, the fourth amplitude detector 7.4, the second switch 21.2, the second the input of which is connected to the output of the adder 17.8, the second amplitude detector 7.2, the switch 13, the second, third and fourth inputs of which are connected to the outputs of the first amplitude detector 7.1, the phase shifter 10 of the stop pulse and the division circuit 12, respectively but, the sixth key 21.6, the second input of which is connected to the output of the comparison unit 23, and the vertically-deflecting plates of the oscilloscope indicator 14, the horizontally-deflecting plates of which are connected to the output of the sawtooth voltage generator 9.

A frequency counter 5 is connected in series to the second output of the first radio path 6.1, the second input of which is connected to the output of the stop pulse former 10, the fourth key 21.4, the second input of which is connected to the output of the comparison unit 23, and the first memory unit 4.1, the second input of which is connected to the output of the former 10 pulse stop. To the output of the first amplitude detector 7.1, a third key 21.3 is connected in series, the second input of which is connected to the output of the stop pulse generator 10, a time interval meter 22, a second memory unit 4.2, the second input of which is connected to the output of the input device 24, the comparison unit 23, the second and third the inputs of which are connected to the outputs of the frequency counter 5 and the meter 22 time intervals, respectively, and the fifth key 21.5, the second input of which is connected to the output of the meter 22 time intervals, and the output is connected to the third input the first- memory block 4.1. The second receiving antenna 2 is made in the form of an antenna system consisting of a vibrator 2.1 and a loop antenna 2.2 located on the platform 28 and connected through the ninth adder 17.9 to the inputs of the third narrow-band filter 15.3 and the fifth adder 17.5. The radiation pattern control unit 3 is made in the form of a series-connected unit 26 for generating the control voltage of the motor 27 connected through a gearbox 29 to the platform 28. The gearbox 29 is equipped with an angle indicator 30. The seventh key 21.7, the second input of which is connected to the output of the stop pulse former 10, and the phase detector 25, the second input of which is connected to the output of the second key 21.2 and the output is connected to the input of the control voltage generating unit 26, are connected in series to the output of the first key 21.1.

The device operates as follows.

The search for radio frequency signals with frequency hopping is carried out in a given frequency range D _f using a generator 9, which according to a sawtooth law changes the frequency of the local oscillator 8. At the same time, the generator 9 forms a horizontal scan of the oscilloscope indicator 14, which is used as the frequency axis.

The tuning frequency ω _{n1 of} narrow-band filters 15.1 and 15.3 is chosen equal to the intermediate frequency ω _{pr -ω n1} = ω _pr

The tuning frequency ω _{n2 of} narrow-band filters 15.2 and 15.4 is chosen equal to the local oscillator frequency ω _{g −ω n2} = ω _g .

The tuning frequency ω _n3 and the passband Δω _{n1 of the} bandpass filters 18.1 and 18.3 are selected as follows

ω _n3 = (ω ₁ -ω ₂ ) / 2, Δω _n1 = ω ₂ -ω ₁ ,

where ω ₁ and ω ₂ are the frequencies of two possible powerful signals, the appearance of which in the frequency band Δω _p1 , located "to the left" of the passband Δω _{p1 of the} panoramic direction finder, leads to the formation of intermodulation interference.

The tuning frequency ω _n4 and the passband Δω _{p1 of the} bandpass filters 18.2 and 18.4 are selected as follows:

ω _n4 = (ω ₃ -ω ₄ ) / 2, Δω _n2 = ω ₄ -ω ₃ ,

where ω ₃ and ω ₄ are the frequencies of two possible powerful signals, the appearance of which in the frequency band Δω _p2 , located "to the right" of the passband Δω _{p of the} panoramic direction finder, will lead to the formation of intermodulation interference.

The first receiving antenna 1 has a circular radiation pattern, and the second receiving antenna 2 has a cardioid radiation pattern (Fig. 5). Moreover, the second receiving antenna 2 is made in the form of an antenna system consisting of a vibrator 2.1 and a loop antenna 2.2, located on the platform 28 and connected through the ninth adder 17.9 to the inputs of the third narrow-band filter 15.3 and the fifth adder 17.5.

Received signals from a frequency hopping radio station:

u ₁ (t) = U ₁ cos (ω ₀ t + φ ₁ );

u ₂ (t) = U ₂ cos (ω ₀ t + φ ₁ ), 0≤t≤T ₀ ,

where U ₁ , U ₂ , ω ₀ , ω ₁ , ω ₂ , T ₀ are the amplitudes, carrier frequency, initial phases and the duration of the signals from the outputs of the receiving antennas 1 and 2 through the adders 17.1-17.7, 17.9, for which only one shoulder, are fed to the first inputs of the radio paths 6.1-6.4, to the second inputs of which the local oscillator voltage 8 is applied:

u _g1 (t) = U _g cos (ω _g t + πγt ² + φ _g ),

u _g2 (t) = U _g cos (ω _g t + πγt ² + φ _g + 90 °), 0≤t≤T _p ,

where U _g , ω _r , φ _g , T _p - amplitude, initial frequency, initial phase and the period of tuning of the local oscillator;

- скорость перестройки частоты гетеродина (скорость «просмотра» заданного диапазона частот D_f).

- the frequency tuning frequency of the local oscillator (speed "viewing" a given frequency range D _f )

Each radio path 6.1 (6.2-6.4) is a series-connected mixer, the second input of which is connected to the output of the local oscillator 8, and an intermediate frequency amplifier. At the outputs of the mixers, combinational frequency voltages are generated. Amplifiers of intermediate frequencies are allocated only the voltage of the intermediate (differential) frequency. Therefore, the following voltages are formed at the outputs of the radio paths 6.1, 6.2, 6.3, 6.4:

u _pr1 (t) = U _pr1 cos (ω _pr t-πγt ² + φ _pr1 ),

u _pr2 (t) = U _pr2 cos (ω _pr t-πγt ² + φ _pr2 ),

_PR3 u (t) = U _pr1 cos (ω _ave t-πγt ² + φ _pr1 -90 °),

_WP4 u (t) = U _np2 cos (ω _ave t-πγt _np2 ² + φ -90 °), 0≤t≤T ₀

Where

k ₁ - transmission coefficient of radio paths;

ω _CR = ω ₀ -ω _g intermediate frequencies;

φ _pr1 = φ ₁ -φ _g ; φ _CR2 = φ ₂ -φ _g ,

which in the passband of radio paths Δω _p (passband of a panoramic receiver-direction finder) acquire forced linear frequency modulation (LFM).

The _voltages u _pr3 (t) and u _pr4 (t) from the outputs of the radio _paths 6.3 and 6.4, respectively, are fed to the input of the phase shifters 19.2 and 19.3 by 90 °, at the output of which the voltages are formed:

u _pr5 (t) = U _pr1 cos (ω _pr t-πγt ² + φ _pr1 -90 ° + 90 °) = U _pr1 cos (ω _pr t-πγt ² + φ _pr1 )

u _pr6 (t) = U _pr2 cos (ω _pr t-πγt ² + φ _pr2 -90 ° + 90 °) = U _pr2 cos (ω _pr t-πγt ² + φ _pr2 ), 0≤t≤T ₀ .

Voltages U _CR3 (t) and U _CR5 (t), U _CR2 (t) and U _CR6 (t) are supplied to two inputs of voltage adders 17.4 and 17.8:

u _Σ1 (t) = U _Σ1 cos (ω _pr t-πγt ² + φ _pr1 );

u _Σ2 (t) = U _Σ2 cos (ω _pr t-πγt ² + φ _pr2 ), 0≤t≤T ₀ ,

Where

These voltages are applied to the first inputs of the multipliers 20.1 and 20.2. accordingly, the second inputs of which receive the received signals u ₁ (t) and u ₂ (t) from the outputs of the adders 17.3 and 17.7. The outputs of the multipliers 20.1 and 20.2 are formed voltage:

u ₃ (t) = U ₃ cos (ω _g t + πγt ² + φ _g );

u ₄ (t) = U ₄ cos (ω _g t + πγt ² + φ _g ), 0≤t≤T ₀ ,

;

;Where

;

;

k ₂ - transmission coefficient of the multipliers, which are allocated by narrow-band filters 15.2 and 15.4, respectively, are detected by amplitude detectors 7.3 and 7.4 and are fed to the control inputs of the keys 21.1 and 21.2, opening them. Keys 21.1 and 21.2 in the initial state are always closed. In this case, the total voltages u _Σ1 (t) and u _Σ2 (t) through the public keys 21.1 and 21.2, respectively, are supplied to the inputs of the amplitude detectors 7.1 and 7.2;

Therefore, at the outputs of the adders 17.4 and 17.8, the input signals from the corresponding frequency range are sequentially allocated in time. After amplitude detection in amplitude detectors 7.1 and 7.2, these signals are fed to the vertically-deflecting plates of the cathode ray tube (oscilloscope indicator) 14, to the horizontally-deflecting plates of which a sweep voltage is supplied from the output of the sawtooth voltage generator 9. As a result, a spectral density pattern in the corresponding frequency range is formed on the screen of the indicator 14. Due to the fact that the same LFM signal from the output of the local oscillator 8 is supplied to the reference inputs of the radio paths 6.1-6.4, the same input signal is observed at the outputs of the adders 17.4 and 17.8 at any time. The amplitude of the signal at the output of the adder 17.4 does not depend on the direction of arrival of the input signal due to the type of radiation pattern of the first receiving antenna 1 (Fig. 5). The second antenna 2 has a cardioid radiation pattern, the rotation of which is carried out by the motor 27. The envelope of the spectra of the input signals from the outputs of the amplitude detectors 7.1 and 7.2 are fed to the input of the division circuit 12 and switch 13. The switch 13 is used to connect one of the signals to the input of the indicator 14: from the outputs adders 17: 4 and 17.8 and the output of the division circuit 12.

To implement the selection of signals in the direction using the motor 27, the cardioid radiation pattern of the antenna system 2, consisting of a vibrator 2.1 and a loop antenna 2.2, is rotated until the zero dip is combined with the direction of arrival of the signals (Fig. 5). This mode is a search mode of radio signals with pseudo-random tuning of the operating frequency. The amplitudes of the signals from this direction at the output of the adder 17.8 are close to zero, therefore, at the output of the division circuit 12, dividing the amplitude of the signal from the output of the adder 17.4 (amplitude detector 7.1) by the amplitude of the signal from the output of the adder 17.8 (amplitude detector 7.2), at this point in time the signal will be maximum. The moment of maximizing the ratio is visually fixed on the screen of the oscilloscope indicator 14. The threshold value is set so that the threshold block 11 is triggered only by signals coming from the zero direction.

When the threshold block 11 is activated, the driver 10 generates a stop pulse, which stops the sawtooth voltage generator 9, starts the frequency counter 5, allows the signal to pass to the indicator 14, opens the keys 21.3 and 21.7. The keys 21.1,21.2 and 21.7 in the initial state are always closed, and the keys 21.4 and 21.5 are open.

The voltage U _Σ1 (t) from the output of the adder 17.4 through the public keys 21.1 and 21.7 is supplied to the first input of the phase detector 25, the second input of which is supplied with the voltage U _Σ2 (t) from the output of the adder 17.8 through the public key 21.2.

When the zero failure of the antenna system 2 coincides with the direction of arrival of the signals (Fig. 5), there is no voltage at the output of the phase detector 25.

If the detected frequency hopping radio station is mobile, then when it moves at the output of the phase detector 25 and the control voltage generating unit 26, a control voltage appears, the amplitude of which is determined by the degree of deviation of the zero dip of the antenna system 2 from the direction of arrival of the signals, and the polarity by the side of the deviation. This voltage acts on the motor 27, connected through a gear 29 to the platform 28, so that the resulting mismatch is eliminated.

A tracking system consisting of a phase detector 25, a control voltage generating unit 26, a motor 27, a gearbox 29, and a platform 28 on which an antenna system 2, consisting of a vibrator 2.1 and a loop antenna 2.2 is installed, is adjusted so that the zero dip of the antenna system 2 (cardioids) always coincides with the direction of arrival of the signals. Moreover, the angular movement of the direction-finding radio station with frequency hopping during operation is constantly compensated by the corresponding rotation of the platform 28.

Thus, masking signals coming from other directions are eliminated, and it becomes possible to detect weak short-term signals with frequency hopping, measure and record the values of their frequencies.

To eliminate signals that are not of interest for radio monitoring (for example, television broadcasting transmitters, beacons, means of own communication, etc.), a time-frequency mask is used, which is generated in the proposed device, recorded and stored in the memory unit 4.2.

In this case, pulses appear from the output of the amplitude detector 7.1 at the moment of triggering of the threshold block 11 from signals coming from the zero direction. In addition, in the block 4.2 of the memory can be entered using the device 24 input additional information from the operator. Using this information, a time-frequency mask of the signals prohibited for subsequent signal processing is generated and stored in the memory block 4.2.

In block 23, the comparison compares the values of the frequencies at which the signals of the transmitters are detected, the times of receiving signals at these frequencies and the duration with the time-frequency mask stored in block 4.2 of the memory. In case of coincidence of frequencies and the presence of a time inhibit mask, a signal is generated in the comparison block 23, which prohibits processing at these frequencies and time intervals, as well as recording in the memory block 4.1. This signal is supplied to the control inputs of the keys 21.4, 21.5, 21.6 and closes them. In the initial state, the specified keys are always open.

Therefore, in block 4.2 of the memory will be recorded frequencies, moments of reception and duration of only valuable signals and newly emerging radiation.

The operation of the device described above corresponds to the case of receiving useful signals with frequency hopping on the main channel at a frequency of ω ₀ (figure 2). If false signals (interference) are received on the mirror channel at a frequency of ω ₃

u _z1 (t) = U _z1 cos (ω _z t + φ _z1 );

u _z2 (t) = U _z2 cos (ω _z t + φ _z2 ), 0≤t≤T _z ,

then the following voltages are distinguished by radio paths 6.1-6.4:

u _pr7 (t) = U _pr7 · cos (ω _pr t + πγt ² + φ _pr7 ),

u _pr8 (t) = U _pr8 · cos (ω _pr t + πγt ² + φ _pr8 ),

u _pr9 (t) = U _pr7 · cos (ω _pr t + πγt ² + φ _pr7 + 90 °),

u _pr10 (t) = U _pr8 · cos (ω _pr + πγt ² + φ _pr8 + 90 °), 0≤t≤T _s ,

Where

U _p - the amplitude of the voltage at the output of the generator 9;

_straight ω = ω _r -ω _s - intermediate frequency;

φ _pr7 = φ _g -φ _z1 ; φ _pr8 = φ _g -φ _z2 .

Voltages u _pr9 (t) and u ₁₀ (t) from the outputs of the radio paths 6.3 and 6.4, respectively, are supplied to the inputs of the phase shifters 19.2 and 19.3 by 90 °, at the outputs of which the voltages are formed:

u _pr11 (t) = U _pr7 · (ω _pr t + πγt ² + φ _pr7 + 90 ° + 90 °) = - U _pr7 · cos (ω _pr t + πγt ² + φ _pr7 );

u _pr12 (t) = U _pr8 · (ω _pr t + πγt ² + φ _pr8 + 90 ° + 90 °) = - U _pr8 · cos (ω _pr t + πγt ² + φ _pr8 ), 0≤t≤T _s .

The _voltages U _CR7 (t) and U _CR11 (t) and U _CR8 (t) and U _CR12 (t) supplied to the two inputs of the adders 17.4 and 17.8 are compensated at the outputs.

Consequently, false signals (interference) received through the mirror channel at a frequency of ω ₃ are suppressed using external “rings”, each of which consists of radio paths 6.1 and 6.3 (6.2 and 6.4), a local oscillator 8, phase shifters 19.1 and 19.2 (19.3) , adder 17.4 (17.8) and which implement the phase compensation method.

For a similar reason, false signals (interference) received on the first combination channel at a frequency ω _{k2 are also suppressed} (FIG. 2),

u _k1 (t) = U _k1 cos (ω _k2 t + φ _k1 );

u _k2 (t) = U _k2 cos (ω _k2 t + φ _k2 ), 0≤t≤T _k2 ,

then the following voltages are distinguished by radio paths 6.1-6.4:

u _pr13 (t) = U _pr13 cos (ω _pr t-πγt ² + φ _pr13 ),

u _pr14 (t) = U _pr14 cos (ω _pr t-πγt ² + φ _pr14 ),

u _pr15 (t) = U _pr13 cos (ω _pr t + πγt ² + φ _pr13 -90 °),

u _pr16 (t) = U _pr14 cos (ω _pr t + πγt ² + φ _pr14 -90 °), 0≤t≤T _k2 ,

Where

_straight ω = ω _k2 -2ω _g - intermediate frequency;

φ _pr13 = φ _k1 -φ _g ; φ _pr14 = φ _k2 -φ _g2 .

The _voltages U _pr15 (t) and U _pr16 (t) from the outputs of the radio _paths 6.3 and 6.4, respectively, are supplied to the inputs of the phase shifters 19.2 and 19.3 by 90 °, at the outputs of which the voltages are formed:

u _pr17 (t) = U _pr13 cos (ω _pr t-πγt ² + φ _pr13 -90 ° + 90 °) = U _pr13 cos (ω _pr t-πγt ² + φ _pr13 );

u _pr18 (t) = U _pr14 cos (ω _pr t-πγt ² + φ _pr14 -90 ° + 90 °) = U _pr14 cos (ω _pr t-πγt ² + φ _pr14 ), 0≤t≤T _k2 .

Voltages U _CR13 (t) and U _CR8 (t) and U _CR14 (t) and U _CR18 (t) supplied to the two inputs of the adders 17.4 and 17.8, at the outputs of which total voltages are formed:

u _Σ3 (t) = U _Σ3 cos (ω _pr t-πγt ² + φ _pr13 );

u _Σ4 (t) = U _Σ4 cos (ω _pr t-πγt ² + φ _pr14 ), 0≤t≤T _k2 ,

where U _Σ3 = 2U _pr13 ; U _Σ4 = 2U _pr14 .

These voltages are applied to the first inputs of the multipliers 20.1 and 20.2, the second inputs of which receive the received signals u _k1 (t) and u _k2 (t) from the outputs of the adders 20.1 and 20.2, the voltages are formed:

u ₅ (t) = U ₅ cos (2ω _g t + 2πγt ² + φ _g );

u ₆ (t) = U ₆ cos (2ω _g t + 2πγt ² + φ _g ), 0≤t≤T _k2 ,

,Where

,

which do not apply to the passband of narrow-band filters 15.2 and 15.4. The keys 21.1 and 21.2 do not open and false signals (interference) received on the second combinational channel at a frequency ω _k2 are suppressed. In this case, two internal “rings” are used, each of which consists of a multiplier 20.1 (20.2), a narrow-band filter 15.2 (15.4), an amplitude detector 7.3 (7.4), a key 21.1 (21.2) and implements the method of narrow-band filtering.

If false signals (interference) are received on the direct channel at an intermediate frequency ω _CR :

u _p1 (t) = U _p1 cos (ω _pr t + φ _p1 );

_n2 u (t) = U _{n 2} cos (ω _ave t + φ _n2), 0≤t≤T ₁

then from the outputs of the receiving antennas 1 and 2, they arrive at the first inputs of the adders 17.1 and 17.5, are distinguished by narrow-band filters 15.1 and 15.3 tuned to the intermediate frequency ω _pr , are phase inverted by 180 ° in phase inverters 16.1 and 16.4:

u _p3 (t) = - U _p1 cos (ω _pr t + φ _p1 );

_n4 u (t) = - U _{n 2} cos (ω _ave t + φ _n2), 0≤t≤T _1.

The _voltages u _p1 (t) and u _p3 (1), u _p2 (t) and u _p4 (t) supplied to the two inputs of the adder 17.1 and 17.5 are compensated at their inputs.

Consequently, false signals (interference) received through the direct passage channel at an intermediate frequency are suppressed by two filter plugs, each of which consists of a narrow-band filter 15.1 (15.3), a phase inverter 16.1 (16.4), an adder 17.1 (17.5) and implements a phase compensation method .

If two powerful false signals (interference) at frequencies ω ₁ and ω ₂ or several powerful signals (interference) appear simultaneously in the frequency band Δω _p1 "to the left" of the passband Δω _{p of the} panoramic direction-finder receiver, which can generate intermodulation interference, then they stand out bandpass filters 18.1 and 18.3, are inverted in phase by 180 ° phase inverters 16.2 and 16.5 are compensated in the adders 17.2 and 17.6 (figure 3).

Consequently, false signals (interference) received in the frequency band Δω _p1 and generating intermodulation interference are suppressed by two filter plugs, each of which consists of a bandpass filter 18.1 (18.3), a phase inverter 16.2 (16.5), an adder 17.2 (17.6) and implements phase compensation method.

If two powerful false signals (interference) at frequencies ω ₃ and ω ₄ or several powerful signals (interference) appear simultaneously in the frequency band Δω _p2 "to the right" of the passband Δω _{n of the} panoramic direction finding receiver that can generate intermodulation interference, then they are highlighted bandpass filters 18.2 and 18.4, phase inverted 180 ° phase inverters 16.3 and 16.6, compensated in the adders 17.3 and 17.7 (figure 4).

Therefore, false signals (interference) received in the frequency band Δω _p2 and generating intermodulation interference are suppressed by two filter plugs, each of which consists of a bandpass filter 18.2 (18.4), a phase inverter 16.3 (16.6), an adder 17.3 (17.7) and implements phase compensation method.

Suppression of false signals (interference) received via additional channels provides increased selectivity and noise immunity of the panoramic receiver-indicator, as well as eliminates the ambiguity in determining the grid of frequencies used.

Thus, the proposed device in comparison with the prototype provides control over the operation of mobile radios with pseudo-random tuning of the operating frequency. This is achieved by the use of a follow-up consisting of a phase detector 25, a control voltage generating unit 26, a motor 27, a gearbox 29 and a platform 28 on which the antenna system 2, consisting of a vibrator 2.1 and a loop antenna 2.2, is placed. Thus, the functionality of the device is expanded.

Claims (1)

A device for monitoring the operation of radio stations with pseudo-random tuning of the operating frequency, comprising a first receiving antenna, a first narrow-band filter, a first phase inverter, a first adder, the second input of which is connected to the output of the first receiving antenna, a first bandpass filter, a second phase inverter, a second adder, and a second input which is connected to the output of the first adder, the second bandpass filter, the third phase inverter, the third adder, the second input of which is connected to the output of the second adder, the first a diotract, the second input of which is connected to the first output of the local oscillator, the fourth adder, the first multiplier, the second input of which is connected to the output of the third adder, the second narrow-band filter, the third amplitude detector, the first key, the second input of which is connected to the output of the fourth adder, the first amplitude detector, a division circuit, the second input of which is connected to the output of the second amplitude detector, a threshold block, a stop pulse shaper, a sawtooth voltage generator and horizontally deflecting plates oscilloscope indicator connected in series to the output of the sawtooth generator, a local oscillator, the first phase shifter 90 °, the third radio path, the second input of which is connected to the output of the third adder, and the second phase shifter 90 °, the output of which is connected to the second input of the fourth adder, connected in series third narrow-band filter, fourth phase inverter, fifth adder, third band-pass filter, fifth phase inverter, sixth adder, the second input of which is connected to the output of the fifth adder, even the fourth bandpass filter, the sixth phase inverter, the seventh adder, the second input of which is connected to the output of the sixth adder, the second radio path, the second input of which is connected to the first output of the local oscillator, the eighth adder, the second multiplier, the second input of which is connected to the output of the seventh adder, the fourth narrow-band filter, the fourth amplitude detector, the second key, the second input of which is connected to the output of the eighth adder, the second amplitude detector, the switch, the second, third and fourth inputs of which are connected to the outputs the first amplitude detector, the stop pulse generator and the dividing circuit, respectively, connected in series to the output of the seventh adder is a fourth radio path, the second input of which is connected to the output of the first phase shifter 90 °, and the third phase shifter 90 °, the output of which is connected to the second input of the eighth adder, in series a frequency meter connected to the second output of the first radio path, the second input of which is connected to the output of the stop pulse shaper, the fourth key, the second input of which is connected to the output of the comparison unit, and the first memory block, the second input of which is connected to the output of the stop pulse shaper, the third key is connected in series to the output of the first amplitude detector, the second input of which is connected to the output of the stop pulse shaper, a time interval meter, the second memory block, the second input of which connected to the output of the input device, a comparison unit, the second and third inputs of which are connected to the outputs of the frequency meter and time meter, respectively, and the fifth key, the second in One of which is connected to the output of the time interval meter, and the output is connected to the third input of the first memory block, vertically deflecting plates of the oscilloscope indicator through the sixth key are connected to the outputs of the switch and the comparison unit, the second receiving antenna and the radiation pattern control unit, characterized in that it is equipped the ninth adder, seventh key, phase detector, angle indicator, platform and gear, the second receiving antenna is made in the form of an antenna system consisting of vi of the horn and antenna mounted on the platform and connected through the ninth adder to the inputs of the third narrow-band filter and the fifth adder, the radiation pattern control unit is made in the form of series-connected control voltage generation unit and a motor connected through the gearbox to the platform, the gearbox is equipped with an angle indicator, to the seventh key, the second input of which is connected to the output of the stop pulse generator, and a phase detector, the second input of which th connected to the output of the second switch, and an output connected to the input unit generating a control voltage.

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