RU2444461C1 - System for detecting and locating person in distress on water - Google Patents

Abstract

FIELD: physics. ^ SUBSTANCE: invention relates to rescue equipment. The system for detecting and locating a person in distress on water has lifejacket worn by a person and apparatus mounted on a helicopter. The lifejacket has light sources (1) and (2), a power source (3), cables (4) and (5), cartridges (6) and (7), membranes (8) and (9), levers (10) and (11), contacts (12) and (13), an air-tight pneumatic pipeline (14), cavities (15) and (16), sealing rings (17) and (18), transmitters (19) and (20), and transmitting antennae (21) and (22). Each transmitter has a drive oscillator (66), a pseudorandom sequence generator (67), a phase-shift modulator (68) and a power amplifier (69). The apparatus, which is mounted on a helicopter, has receiving antennae (23-27), heterodynes (28) and (39), mixers (22-33, 40), first intermediate frequency amplifiers (34-38), a second intermediate frequency amplifier (41), an amplitude detector (42), a recording unit (43), multipliers (44-47, 52, 53), narrow-band filters (48-51, 54, 55, 78), delay lines (56, 57), phase detectors (58, 59, 79), phasemeters (60-63), a motor (64), a reference oscillator (65), a phase-shift keyed signal detector (selector) (70), spectrum analysers (71, 73), a phase doubler (72), a comparator unit (74), a threshold unit (75), a switch (76), and a phase halver (77). ^ EFFECT: high reliability of detecting and locating a person in distress on water by using phase-shift keyed signals. ^ 5 dwg

Description

The proposed system relates to rescue equipment and can be used to detect a person in distress on the water, and determine his location.

Rescue systems and devices are known (ed. Certificate of the USSR No. 385.819, 431.063, 637.298, 765.113, 988.655, 1.348.256, 1.505.840, 1.505.841, 1.588.636, 1.615.054, 1.643.325, 1.664.653 ; RF patents Nos. 2.000.995, 2.009.956, 2.038.259, 2.043.259, 2.051.838, 2.177.437, 2.193.990, 2.276.038, 2.363.614; US patents Nos. 3.621.501, 4.889 .511; UK patent No. 1,145.051 and others).

Of the known systems and devices closest to the proposed one is a system for detecting and determining the location of a person in distress on water (RF patent No. 2.177.437, B63C 9/20, 2000), which is selected as a prototype.

The specified system provides increased reliability of detecting a person in distress on the water, and determining its location by using a radio emitter and a helicopter. For direction finding of the distress signal radiation source, the differential-phase method is used, which is implemented on board the helicopter. In this case, the receiving antennas are located at the ends of four opposing rotor blades of the helicopter and rotating around the receiving antenna located above the rotor hub of the helicopter. To increase the accuracy of direction finding of the radio emitter (radio sensor), the receiving antennas are located at the diametrically opposite ends of the rotor blades of the helicopter. The resulting ambiguity in direction finding is eliminated by autocorrelation processing of the received signals.

The location of the distress signal source (radio sensor) is carried out using the measured azimuth values α, elevation angle β and helicopter flight altitude h.

However, the known system does not provide the ability to determine the identity of a person in distress on the water.

An object of the invention is to increase the reliability of detection and location of a person in distress on water by using complex signals with phase shift keying.

The problem is solved in that a system for detecting and determining the location of a person in distress on the water, including, in accordance with the closest analogue, a life jacket worn by a person and containing two light sources, one of which is located in the chest area of the life jacket, and the other in its back area, a current source, two circuit breakers, two communicating sealed containers, each of which is separated from the environment by a membrane, one of the sealed containers is located in the chest area of the life jacket, and the other in the back area of it, two miniature transmitters with transmitting antennas, one of which is located in the chest area of the life jacket and the other in the back area of it, the membrane of each tank is connected to the circuit breaker of the corresponding source light by means of a lever, and both light sources and a transmitter through switches are connected to a current source in parallel, and equipment installed on board the helicopter and consisting of one measuring and four x direction finding channels, wherein the measuring channel consists of a series-connected receiving antenna, a first mixer, the second input of which is connected to the output of the first local oscillator, and an amplifier of the first intermediate frequency, series-connected second oscillator, the sixth mixer, the second intermediate frequency amplifier, amplitude detector and unit registration, each direction finding channel consists of a series-connected receiving antenna, a mixer, the second input of which is connected to the output of the first local oscillator, an amplifier of the first intermediate frequency, a multiplier, the second input of which is connected to the output of the amplifier of the second intermediate frequency, and a narrow-band filter, while the fifth multiplier is connected in series to the output of the first narrow-band filter, the second input of which is connected to the output of the second narrow-band filter, the fifth narrow-band filter and the first phase meter , the first delay line, the first phase detector, the second input of which is connected to the output of the second node, is connected in series to the output of the second narrow-band filter the second filter, and the second phase meter, the sixth multiplier is connected in series to the output of the third narrow-band filter, the second input of which is connected to the output of the fourth narrow-band filter, the sixth narrow-band filter and the third phase meter, the second delay line, the second phase detector, and the second are connected in series to the output of the fourth narrow-band filter the input of which is connected to the output of the fourth narrow-band filter, and the fourth phase meter, the second inputs of the phase meters are connected to the output of the reference generator, the receiving the antenna of the measuring channel is located above the helicopter rotor hub, the receiving antennas of direction finding channels are located at the ends of the rotor blades of the helicopter, the engine is kinematically connected to the helicopter rotor and the reference generator, differs from the closest analogue in that it is equipped with two spectrum analyzers, a phase doubler, a phase divider by two, a comparison unit, a threshold unit, a key, a seventh narrow-band filter and a third phase detector, each transmitter being made in the form of series-connected its generator, phase manipulator, the second input of which is connected to the output of the pseudo-random sequence generator, and the power amplifier, a phase doubler, a second spectrum analyzer, a comparison unit, the second input of which is connected to the output through the first spectrum analyzer, are connected to the output of the amplifier of the first intermediate frequency of the measuring channel the amplifier of the first intermediate frequency, a threshold block and a key, the second input of which is connected to the output of the amplifier of the first intermediate frequency, and the output is connected a second divider, a seventh narrow-band filter and a third phase detector, the second input of which is connected to the key output and the output is connected to the second input of the registration unit, are connected to the second input of the sixth mixer, to the output of the phase doubler.

Figure 1 schematically shows a life jacket with light sources 1, 2 and transmitters 19, 20 with transmitting antennas 21, 22, worn on a person; figure 2 is the same section. The structural diagram of the transmitter 19 (20) is presented in figure 3. The structural diagram of the equipment installed on board the helicopter is presented in figure 4. A geometric arrangement of receiving antennas on a helicopter and an RD radio sensor located on a person in distress on water is shown in FIG. 5.

The life jacket consists of light sources 1 and 2, energy source 3, cables 4 and 5 for supplying energy to light sources 1, 2 and transmitters 19, 20 with transmitting antennas 21, 22, cartridges 6 and 7, membranes 8, 9 and associated by them of levers 10 and 11 with contacts 12 and 13, as well as of a sealed pneumatic line 14, connecting sealed air cavities 15 and 16. The places of entry of cables 4 and 5 from energy source 3 in cavities 15 and 16 are sealed with sealing rings 17 and 18. Light source 1 and the transmitter 19, the light source 2 and the transmitter 20 are connected in parallel to the source 3 energy.

Each transmitter 19 (20) contains a serially connected master oscillator 66, a phase manipulator 68, the second input of which is connected to the output of a pseudo-random sequence generator (PSP) 67, and a power amplifier 69, the output of which is connected to the transmitting antenna 21 (22).

The equipment placed on board the helicopter contains a measuring channel and four direction finding channels. The measuring channel consists of a series-connected receiving antenna 23, a mixer 29, the second input of which is connected to the output of the first local oscillator 28, an amplifier 34 of the first intermediate frequency, a phase doubler 72, a second spectrum analyzer 73, a comparison unit 74, the second input of which through the first spectrum analyzer 71 connected to the output of the amplifier 34 of the first intermediate frequency, the threshold block 75, the key 76, the second input of which is connected to the output of the amplifier 34 of the first intermediate frequency, the sixth mixer 40, the second input of which is connected to Exit second local oscillator 39, the amplifier 41 of the second intermediate frequency, amplitude detector 42 and the register unit 43. A phase divider 77 into two, a seventh narrow-band filter 78 and a third phase detector 79, the second input of which is connected to the output of the key 76 and the output is connected to the second input of the registration unit 43, are connected in series to the output of the phase doubler 72. Spectrum analyzers 71 and 73, a phase doubler 72, a comparison unit 74, a threshold unit 75, and a key 76 form a detector (selector) 70 of complex phase-shift (PSK) signals.

Each direction finding channel consists of a series-connected receiving antenna 24 (25, 26, 27), a mixer 30 (31, 32, 33), the second input of which is connected to the output of the first local oscillator 28, amplifier 35 (36, 37, 38) of the first intermediate frequency , a multiplier 44 (45, 46, 47), the second input of which is connected to the output of the amplifier 41 of the second intermediate frequency, and a narrow-band filter 48 (49, 50, 51). The fifth multiplier 52, the second input of which is connected to the output of the second narrow-band filter 49, the fifth narrow-band filter 54 and the first phase meter 60, are connected in series to the output of the first narrow-band filter 48. The first delay line 56, the first phase detector 58, are connected in series to the output of the second narrow-band filter 49. the second input of which is connected to the output of the second narrow-band filter 49, and the second phase meter 61. To the output of the third narrow-band filter 50 are connected in series: the sixth multiplier 53, the second input of which connected to the output of the fourth narrow-band filter 51, the sixth narrow-band filter 55 and the third phase meter 62. The second delay line 57, the second phase detector 59, the second input of which is connected to the output of the fourth narrow-band filter 51, and the fourth phase meter 63 are connected to the output of the fourth narrow-band filter 51. The second inputs of the phase meters 60-63 are connected to the output of the reference generator 65. A receiving antenna 23 of the measuring channel is located above the hub of the helicopter rotor, receiving antennas 24-27 of direction finding channels are placed at the end ah blades of the rotor of the helicopter, the engine 64 is kinematically connected with the rotor of the helicopter and the reference generator 65.

The system operates as follows.

In the position shown in FIG. 1, the ambient pressure P ₂ on the membrane 9 is greater than the atmospheric pressure P ₁ on the membrane 8. The membrane 9 is in a preloaded position and the membrane 8 is in a depressed state. Accordingly, the lever 11 presses the contact 13 from the light source 2 and the transmitter 22, and the lever 10 presses the contact 12 to the light source 1 and the transmitter 19. The light source 1 is on, the transmitter 19 is emitting a distress signal, the light source 2 is off, the transmitter 20 is not working.

If a person makes a 180 ° rotation about the horizontal axis, then the light source 2 and the transmitter 20 with the transmitting antenna 22 are at the top.

The pressure of the medium on the membrane 8 becomes greater than on the membrane 9, the membrane 8 is pressed, the lever 10 opens the contact 12 with the light source 1 and the transmitter 19 with the transmitting antenna 21. The circuit is open, the light source 1 goes out, the transmitter 19 is turned off. At the same time, air from the cavity 15 flows through the line 14 into the cavity 16, the membrane 9 is squeezed out, the lever 11 closes the contact 13 with the light source 2 and the transmitter 20 with the transmitting antenna 22. The light source 2 lights up, and the transmitter 20 emits a distress signal.

At night and in good weather, the light source can be detected visually at a considerable distance. However, in daylight and in bad weather, it is difficult to detect a light source.

Radio emission is weatherproof and provides distress signal transmission over long distances. In this case, the distress signal (SOS) is emitted periodically with a certain period T _{p of} duration T _s at a certain frequency w _c , which is allocated specifically for transmitting a distress signal and is not involved in transmitting other information.

Receiving equipment is placed on board the helicopter.

The presence of a rotary rotor of the helicopter can be used to determine the direction of the distress signal to the radiation source (RD sensor) using a device whose antennas are located at the ends of the rotor blades.

By measuring the direction angles to the distress signal source α, β and knowing the flight altitude h, it is possible to determine the location of the indicated source (a person in distress on water).

When the transmitter 19 (20) is turned on, the master oscillator 66 generates a high-frequency oscillation

U _c (t) = U _c Cos (w _c t + φ _s ), 0≤t≤T _s ,

which is fed to the first input of the phase manipulator 68, to the second input of which a modulating code M (t) is supplied from the output of the pseudo-random sequence generator (PSP) 67. At the output of the phase manipulator 68, a complex signal with phase shift keying (PSK) is formed

u ' _c (t) = U _c · Cos [w _c t + φ _k (t) + φ _s ], 0≤t≤T _s ,

where φ _к (t) = {0, π} is the manipulated phase component that displays the phase manipulation law in accordance with the modulating code M (t), and φ _к (t) = const for кτ ₃ <t <(к + 1) τ _e and can change abruptly at t = kτ _e , i.e. at the boundaries between elementary premises (k = 1, 2, ..., N-1);

τ _e , N is the duration and number of chips that make up the signal with a duration of T _s (T _s = N · τ _e ),

which, after amplification in the power amplifier 69, enters the transmitting antenna 21 (22) and is radiated by it into the air. At the same time, the modulating code M (t) is the identification number of a person in distress on the water, and contains brief information about him, for example, last name, first name, middle name, year of birth, country, company, etc. The receiving antennas 23-27 pick up the following PSK signals:

,

,

,

,

where ± Δw is the instability of the carrier frequency of the signals due to various destabilizing factors, including the Doppler effect;

R is the radius of the circle on which the receiving antennas 24-27 are located;

Ω = 2πR - rotation speed of the receiving antenna 23 (rotational speed of the rotor of the helicopter);

α, β - bearing and elevation angle of the distress signal source;

λ is the wavelength

which enter the first inputs of the mixers 29-33, the second inputs of which the voltage of the first local oscillator 28

The signs “+” and “-” in front of the values 2πR / λcos (Ω-α) and 2πR / λcos (Ω-β) correspond to diametrically opposite locations of the antennas 24 and 25, 26 and 27 at the ends of the rotor blades of the helicopter relative to the receiving antenna 23, located above the helicopter rotor hub.

At the outputs of the mixers 29-33, voltages of combination frequencies are generated. Amplifiers 34-38 distinguish the voltage of the first intermediate frequency:

,

,

,

,

;Where

;

w _up1 = w _c -w _g1 is the first intermediate frequency;

φ _up1 = φ _c -φ _g1 ,

To ₁ - gear ratio of the mixers.

The voltage u _up1 (t) from the output of the amplifier 34 of the first intermediate frequency is fed to the input of the detector (selector) 70 QPSK signals, consisting of spectrum analyzers 71 and 73, a phase doubler 72, a comparison unit 74, a threshold unit 75, and a key 76. harmonic oscillation is formed at the output of the phase doubler 72

u _up6 (t) = U _up6 · Cos [2 (w _up1 ± Δw) t + 2φ _up1 ], 0≤t≤T _s ,

;Where

;

K ₂ is the transmission coefficient of the multiplier.

As a phase doubler 72, a multiplier can be used, on the two inputs of which the same voltage u _up1 (t) is supplied. Since 2φ _K (t) = {0, 2π}, phase-shift keying is already absent in harmonic oscillation.

The width of the spectrum Δf ₂ harmonic oscillations (second harmonic signal) is determined by the duration of the signal

Δf ₂ = 1 / T _c ,

and the width _c Δf spectrum PSK signal determined by the duration τ _e chips

Δf _c = 1 / τ _e .

Therefore, when the phase of a complex QPSK signal is doubled, its spectral width collapses N times

Δf _c / Δf ₂ = N.

This circumstance makes it possible to detect a complex QPSK signal among other signals and interference even when the signal-to-noise ratio at the receiver input is less than unity.

Voltages U ₁ and U ₂ proportional to Δf _c and Δf _2, respectively, from the outputs of the spectrum analyzers 71 and 73, are supplied to the two inputs of the comparison unit 74. Since U ₁ >> U ₂ , a constant voltage is generated at the output of the comparison unit 74, which exceeds the threshold level U of the _pores in the threshold block 75. The threshold level U _pop is selected so that it does not exceed random interference.

When the threshold level U _pores is exceeded, a constant voltage is generated in the threshold block 75, which is supplied to the control input of the key 76, opening it. In the initial state, the key 76 is always closed. The voltage u _up1 (t) from the output of the amplifier 34 of the first intermediate frequency through the public key 76 is supplied to the first input of the mixer 40, the second input of which is supplied with the voltage of the second local oscillator 39

u _g2 (t) = U _g2 Cos (w _g2 t + φ _g2 ).

The output of the mixer 40 is formed voltage Raman frequencies. The amplifier 41 is allocated the voltage of the second intermediate frequency

;Where

;

w _up2 = w _up1 -w _r2 - second intermediate frequency;

φ _up7 = φ _up1 -φ _r2,

which, after detection in the amplitude detector 42, enters the first input of the registration unit 43 and thereby captures the fact of detecting a source of radio emission (a person in distress on water).

The voltage u _up1 (t) from the output of the amplifier 34 of the first intermediate frequency through the public key 74 is simultaneously supplied to the first (information) input of the phase detector 79.

The voltage u _up6 (t) from the output of the phase doubler 72 is fed to the input of the phase divider 77 into two, at the output of which a harmonic oscillation is formed

which is allocated by the narrow-band filter 78, is used as a reference voltage and is supplied to the second (reference) input of the phase detector 79. As a result of synchronous detection, a low-frequency voltage is generated at the output of the phase detector 79

u _n (t) = U _n · Cos · φ _k (t), 0≤t≤T _c ,

;Where

;

K ₃ - the transfer coefficient of the phase detector,

proportional to the modulating code M (t), which is fixed by the registration unit 43.

The voltage u _up7 (t) of the second intermediate frequency from the output of the amplifier 41 of the second intermediate frequency is supplied simultaneously to the second inputs of the multipliers 44-47, the first inputs of which are supplied with the voltage u _up2 (t) -u _up5 (t). The outputs of the multipliers 44-47 form the following voltages:

,

,

,

,

,

;Where

;

K ₂ - transmission coefficient of the multipliers,

which are allocated by narrow-band filters 48-51.

Therefore, useful information about the angles α and β is transferred to the stable frequency w _{g2 of the} second local oscillator 39. Therefore, instability of the carrier frequency of received distress signals caused by various destabilizing factors does not affect the direction finding result, thereby increasing the accuracy of determining the location of the radio emission source.

Moreover, the value Δφ _m = 2πR / λ, which is part of these oscillations and is called the phase modulation index, characterizes the maximum value of the phase deviation of the rotating antennas 24-27 relative to the phase of the antenna 23. The direction finder is more sensitive to changes in the angles α and β, the larger the relative size of the bases R / λ. However, with increasing R / λ, the values of the angular coordinates α and β decrease at which the phase difference exceeds 2π, i.e. ambiguity of counting occurs.

Consequently, for R / λ <1/2, ambiguity of the reference angles α and β occurs. The elimination of this ambiguity by reducing the R / λ ratio usually does not justify itself, since the main advantage of a wide-base system is lost. In addition, in the range of meter and especially decimeter waves, it is often not possible to take small values of R / λ due to design considerations.

To increase the accuracy of direction finding of the RD radio sensor in the horizontal (azimuthal) and vertical (elevation) planes, the receiving antennas 24 and 25, 26 and 27 are located at the ends of four opposite rotor blades of the helicopter. The displacement of signals from four diametrically opposite receiving antennas 24 and 25, 26 and 27 located at the same distance R from the rotor axis of the rotor causes phase modulation, which is identical to the phase modulation obtained with two receiving antennas rotating in a circle, radius R ₁ which are twice as many (R ₁ = 2R).

Indeed, at the output of multipliers 52 and 53, harmonic voltages are formed:

u ₁₀ (t) = U ₁₀ Cos (Ω-α),

u ₁₁ (t) = U ₁₀ Cos (Ω-β), 0≤t≤T _c ,

;Where

;

with the phase modulation index Δφ _m1 = 2πR ₁ / λ (R ₁ = 2R), which are allocated by narrow-band filters 54 and 55, respectively, and fed to the first input of the phase meters 60 and 62, the second input of which is supplied with the voltage of the reference oscillator 65

u ₀ (t) = U ₀ CosΩt.

Phasometers 60 and 62 provide accurate measurement of the angular coordinates α and β.

To eliminate the ambiguity in reading the angles α and β, it is necessary to reduce the phase modulation index without decreasing the R / λ ratio.

This is achieved using two autocorrelators, each of which consists of a delay line 56 (57) and a phase detector 58 (59), which is equivalent to a decrease in the phase index to Δφ _m2 = 2πd ₁ / λ, where d ₁ <R.

At the output of the autocorrelators, voltages are formed:

u ₁₂ (t) = U ₁₂ Cos (Ω-α),

u ₁₃ (t) = U ₁₂ Cos (Ω-β), 0≤t≤T _c

;Where

;

K ₃ - the transfer coefficient of the phase detectors,

with the phase modulation index Δφ _m2 = 2πd ₁ / λ, which are fed to the first input of the phase meters 61 and 63, the second input of which is supplied with voltage U ₀ (t) from the output of the reference oscillator 65. Phase meters 61 and 63 provide an unambiguous measurement of the angular coordinates α and β. Essentially phase meters are two measurement scales. Phasometers 60 and 62 are accurate but ambiguous scales for measuring the angular coordinates α and β, and phase meters 61 and 63 are rough but unambiguous scales for measuring the angular coordinates α and β.

Knowing the height h of the helicopter flight and measuring the angular coordinates α and β, it is possible to accurately and unambiguously determine the location of the source of the distress signal (a person in distress on water).

The on-board equipment mounted on a helicopter is invariant to instability of the carrier frequency of the received signals, since the direction finding of the distress signal source is carried out at a stable frequency w _{g2 of the} second local oscillator 39. The on-board equipment is also invariant to the type of modulation of the received signals if the distress signals have modulation (manipulation) one of the parameters.

For direction finding of the distress signal radiation source, the differential-phase method is used, which is implemented on board the helicopter. In this case, the receiving antennas 24-27 are located at the ends of four opposite rotor blades of the helicopter and rotating around the receiving antenna 23 located above the hub of the helicopter rotor. To increase the accuracy of direction finding of the radio emitter (radio sensor), the receiving antennas are located at the diametrically opposite ends of the helicopter rotor blades. The resulting ambiguity in direction finding is eliminated by autocorrelation processing of the received signals. The angular coordinates α and β are measured using four phase meters 60-63. In this case, the phaseometers 60 and 62 form accurate, but ambiguous scales for measuring the angular coordinates α and β, respectively, and the phaseometers 61 and 63 form rough, but unambiguous scales for measuring the angular coordinates α and β, respectively.

The location of the distress signal source (radio sensor) is carried out using the measured values of azimuth α, angle six β and height h of the flight of the helicopter.

Thus, the proposed system in comparison with the prototype and other technical solutions for a similar purpose provides increased reliability of detection and location of a person in distress on the water. This is achieved by using complex phase shift keyed signals.

These signals allow the use of a new type of selection - structural selection. This means that there is a new opportunity to separate signals operating in the same frequency band and at the same time intervals.

Complex QPSK signals have high energy and structural secrecy.

The energy secrecy of these signals is due to their high compressibility in time or in the spectrum with optimal processing, which reduces the instantaneous radiated power. As a result, a complex QPSK signal at the receiving point may be masked by noise and interference. Moreover, the energy of a complex QPSK signal is by no means small; it is simply distributed over the time-frequency domain so that at each point of this region the signal power is less than the power of noise and interference.

The structural secrecy of complex QPSK signals is due to the wide variety of their shapes and significant ranges of parameter changes, which makes it difficult to optimize or at least quasi-optimal processing of complex QPSK signals of an a priori unknown structure in order to increase the sensitivity of the receiver.

The reference voltage required for the synchronous detection of complex PSK signals is extracted directly from the received PSK signal itself, and it is possible to obtain complete information about a person in distress on water.

On-board equipment mounted on a helicopter is not only invariant to the instability of the carrier frequency of the received FMN signals, but also to phase manipulation, which increases the accuracy of the phase direction finding of a person in distress on water.

Claims (1)

A system for detecting and determining the location of a person in distress on water, including a life jacket worn by a person and containing two light sources, one of which is located in the chest area of the life jacket, and the other in the back area, a current source, two electrical switches chains, two connected tight containers, each of which is separated from the environment by a membrane, one of the tight containers is located in the chest area of the life jacket, and the other in its back area, of miniature transmitters with transmitting antennas, one of which is located in the chest region of the life jacket and the other in its back region, the membrane of each tank is connected to the circuit breaker of the corresponding light source by a lever, and both light sources and transmitters are connected via disconnectors to a current source in parallel, and equipment installed on board the helicopter and consisting of one measuring and four direction finding channels, while the measuring channel consists of In particular, the receiving antenna, the first mixer, the second input of which is connected to the output of the first local oscillator, and the first intermediate frequency amplifier, the second local oscillator in series, the sixth mixer, the second intermediate frequency amplifier, amplitude detector, and the recording unit, each direction finding channel consists of the receiving antenna, mixer, the second input of which is connected to the output of the first local oscillator, an amplifier of the first intermediate frequency, a multiplier, the second input of which o connected to the output of the amplifier of the second intermediate frequency, and a narrow-band filter, while the fifth multiplier is connected in series to the output of the first narrow-band filter, the second input of which is connected to the output of the second narrow-band filter, the fifth narrow-band filter and the first phase meter, the first is connected in series to the output of the second narrow-band filter a delay line, a first phase detector, the second input of which is connected to the output of the second narrow-band filter, and a second phase meter, to the output of the third narrow-band filter The sixth multiplier is connected in series, the second input of which is connected to the output of the fourth narrow-band filter, the sixth narrow-band filter and the third phase meter; the second delay line, the second phase detector, the second input of which is connected to the output of the fourth narrow-band filter, and the fourth are connected to the output of the fourth narrow-band filter phase meter, the second inputs of the phase meters are connected to the output of the reference generator, the receiving antenna of the measuring channel is located above the hub of the helicopter rotor, reception direction finding channel antennas are located at the ends of the rotor blades of the helicopter, the engine is kinematically connected to the helicopter rotor and the reference generator, characterized in that it is equipped with two spectrum analyzers, a phase doubler, a phase divider in two, a comparison unit, a threshold block, a key, and a seventh narrow-band a filter and a third phase detector, each transmitter being made in the form of a serially connected master oscillator, a phase manipulator, the second input of which is connected to the output of the pseudo-generator pre-random sequence, and a power amplifier, a phase doubler, a second spectrum analyzer, a comparison unit, the second input of which is connected through the first spectrum analyzer to the output of the first intermediate frequency amplifier, a threshold block and a key, the second input of which is connected to the output of the amplifier of the first intermediate frequency of the measuring channel connected to the output of the amplifier of the first intermediate frequency, and the output is connected to the second input of the sixth mixer, to the output of the phase doubler are connected in series s on two phases, the seventh narrowband filter and a third phase detector, a second input coupled to an output key, and an output connected to the second input of the recording unit.

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