RU2458815C1 - System for detecting and locating person in distress - Google Patents

Abstract

FIELD: transport.

SUBSTANCE: invention relates to rescue equipment. Proposed system comprises life vest with light sources (1) and (2), power supply (3), cables (4) and (5), cartridges (6) and (7), membranes (8) and (9), levers (10) and (11), contacts (12) and (13), tight air line (14), air chambers (15) and (16), seal rings (17) and (18), transmitters (19) and (20) with transmitting antennas (21) and (22), receiving antennas (23), (24) and (25), mixers (26), (27), (29), (40), (61), (74), (76), (88), (93) and (95), first intermediate frequency amplifiers (30), (31), (34), (62), (75) and (94), multipliers (32), (33), (37), (65), (70), (72), (79), (84), (90), (92) and (100), narrow-band filters (35), (36), (44), (51), (66), (71), (77), (80), (85), (91), (97) and (101), delay line (38), phase detector (45), phase meters (46) and (47), motor (48), reference generator (49), frequency meters (50), (78), (81), (98) and (102), phase inverters (52), (55) and (58), adders (53), (56), (59), (64), (83), local oscillators (28) and (39), +90°-phasers (60) and (63), -90°-phaser (82), band filters (54) and (57), switchers (68) and (87), second intermediate frequency amplifiers(41) and (89), low-frequency filters (42) and (99), registrator (43) and (103), reference frequency units (73) and (96), and logical element OR (104). Proposed system differs from known designs in that it features twofold increase in operating frequency range and limit-type search range without expanding local oscillator frequency tuning range. This results from use of complex frequency-modulated signals received in image channel at w₃ frequency. Note here that said signals are converted at conversion factor used in primary reception channel.

EFFECT: higher efficiency and reliability.

9 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 personal data, location and traffic parameters.

Rescue systems and devices are known (author's certificate of the USSR No. 385819, 431063, 637298, 765113, 988655, 1348256, 1505840, 1588636, 1615054, 1643325, 1664653; RF patents No. 20000005, 2009956, 2038259, 2051838, 2177797, 229437, 229437, 229437, , 2254262; US patents No. 3621501, 4889511; UK patent No. 1145951; Dikarev V.I. Safety, protection and salvation of a person. St. Petersburg, 2007, p.113-156 and others).

Of the known systems and devices closest to the proposed one is the "System for detecting and determining the location of a person in distress on the water" (RF patent No. 2254262, B63C 9/20, 2004), which is selected as a prototype.

The specified system uses a radio sensor, which is equipped with a person in distress on the water, and a helicopter, on board which is installed equipment for direction finding and determining its location. It allows you to determine the personal data of a person in distress on the water, and the parameters of his movement. The following can be attributed to personal data: country, ship, last name, first name, patronymic, year of birth and other information. The movement of a person in distress on water is due to the course, movement of a person by swimming, water and other improvised means.

The known system provides the suppression of false signals (interference) received via additional channels.

However, in some cases, the suppression of false signals (interference) received via additional channels is impractical.

To double the range of the frequency search for signals, the range of operating frequencies without expanding the frequency range of the local oscillator, it is advisable to use false signals (interference) received on the mirror channel at frequency w ₃ , but use them. The conversion of signals in frequency received through the mirror channel at a frequency w ₃ occurs with the same conversion coefficient K _pr as in the main channel at a frequency w _c (Fig. 7). Therefore, the main and mirror channels are equivalent.

An object of the invention is to double the range of operating frequencies, the range of frequency search for signals without expanding the range of frequency tuning of the local oscillator by using signals received on the mirror channel at a frequency w ₃ .

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, two miniature transmitters with transmitting antennas, one of which is located in the chest area of the life jacket, and the other in its back area, a current source, two electronic switches ctric circuit, two communicating sealed containers, each of which is separated from the environment by a membrane, while one of the sealed containers is located in the chest area of the life jacket, and the other in its back region, the membrane of each container is connected to the circuit breaker of the corresponding light source by means of a lever, and both light sources and transmitters through switches are connected in parallel with the current source, and the equipment installed on board the helicopter and consisting of one measuring and two direction finding channels, wherein the measuring channel consists of a series-connected receiving antenna, a fourth narrow-band filter, a first phase inverter, a first adder, the second input of which is connected to the output of a receiving antenna, a first band-pass filter, a second phase inverter, a second adder, the second input of 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 mixer, the second input One of which is connected to the first output of the first local oscillator, first amplifier of the first intermediate frequency, fourth adder, fourth multiplier, the second input of which is connected to the output of the third adder, fifth narrow-band filter, first amplitude detector, first key, the second input of which is connected to the output of the fourth adder, the fourth mixer, the second input of which is connected to the output of the second local oscillator, and the first amplifier of the second intermediate frequency, while to the second output of the first local oscillator the first phase shifter 90 °, the fifth mixer, the second input of which is connected to the output of the third adder, the fourth amplifier of the first intermediate frequency and the second phase shifter 90 °, the output of which is connected to the second input of the fourth adder, each direction finding channel consists of a receiving antenna connected in series , a mixer, the second input of which is connected to the first 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 first amplifier For the second intermediate frequency and the narrow-band filter, the third 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 third narrow-band filter and the first phase meter, the delay line, phase detector are connected in series to the output of the second narrow-band filter , the second input of which is connected to the output of the second narrow-band filter, and the second phase meter, the second inputs of the phase meters are connected to the output of the reference generator, to the output of the first narrow-band filter, the first frequency meter, the arithmetic unit and the first recording unit are connected in series, the receiving antenna of the measuring channel is located above the rotor hub of the helicopter, 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 to the output the first amplifier of the second intermediate frequency is connected in series to the fifth multiplier, the second input of which is connected to the output of the first filter and a lowpass filter, a sixth narrow-band filter, a sixth multiplier, the second input of which is connected to the output of the first amplifier of the second intermediate frequency, and a first low-pass filter, the output of which is connected to the second input of the first recording unit, a sixth mixer is connected in series to the output of the receiving antenna of the measuring channel, the second input of which is connected to the first output of the first block of reference frequencies, the fifth amplifier of the first intermediate frequency, the seventh mixer, the second input of which is connected to the second output the first block of reference frequencies, the seventh narrow-band filter and the second frequency meter, the output of which is connected to the third input of the first recording unit, to the output of the amplifier of the first intermediate frequency of the first direction-finding channel, the seventh multiplier is connected in series, the second input of which is connected to the output of the amplifier of the first intermediate frequency of the measuring channel, the eighth narrow-band filter and the third frequency meter, the output of which is connected to the fourth input of the first registration unit, each transmitter, tanned in a life jacket, contains a serially connected master oscillator, a phase manipulator, the second input of which is connected to the output of the modulating code generator, and a power amplifier, differs from the closest analogue in that it is equipped with a -90 ° phase shifter, fifth adder, eighth, ninth, tenth and eleventh multipliers, ninth, tenth, eleventh and twelfth narrow-band filters, second amplitude detector, second key, eighth, ninth and tenth mixers, second amplifier second intermediate frequency, a second low-pass filter, a fourth and fifth frequency meter, a second reference frequency unit, a second recording unit and an OR logic element, with a -90 ° phase shifter, a fifth adder, the second input of which is connected to the output of the fourth amplifier of the first intermediate frequency with the output of the first amplifier of the first intermediate frequency, the eighth multiplier, the second input of which is connected to the output of the third adder, the ninth narrow-band filter, the second amplitude detector , the second key, the second input of which is connected to the output of the fifth adder, the eighth mixer, the second input of which is connected to the output of the second local oscillator, the second amplifier of the second intermediate frequency, the ninth multiplier, the second input of which is connected to the output of the second low-pass filter, the tenth narrow-band filter, tenth a multiplier, the second input of which is connected to the output of the second amplifier of the second intermediate frequency, the second low-pass filter and the second registration unit, the second input of which is connected to the output of arithmetic nth unit, the ninth mixer is connected in series to the output of the receiving antenna of the measuring channel, the second input of which is connected to the first output of the second block of reference frequencies, the sixth amplifier of the first intermediate frequency, the tenth mixer, the second input of which is connected to the second output of the second block of reference frequencies, the eleventh narrow-band filter and a fourth frequency meter, the output of which is connected to the third input of the second recording unit, to the output of the first amplifier of the first intermediate frequency of the measuring channel The eleventh multiplier is connected in series, the second input of which is connected to the output of the second amplifier of the first intermediate frequency of the first direction-finding channel, the twelfth narrow-band filter and the fifth frequency meter, the output of which is connected to the fourth input of the second recording unit.

Figure 1 schematically shows a life jacket with light sources 1, 2, transmitters 19, 20 with transmitting antennas 21, 22, worn on a person; figure 2 is the same section. The structural diagram of the equipment installed on board the helicopter is presented in figure 3. The structural diagram of the transmitter is presented in figure 4. Timing diagrams explaining the operation of the system are depicted in figure 5. The geometric arrangement of the receiving antennas on the helicopter is shown in Fig.6. The frequency diagram explaining the process of formation of additional (mirror and Raman) reception channels is shown in Fig.7. Examples of intermodulation interference are shown in FIGS. 8 and 9.

The life jacket also contains an energy source 3, cables 4 and 5 for supplying energy to light sources 1, 2 and transmitters 19, 20, cartridges 6, 7, membranes 8, 9 and associated levers 10, 11 with contacts 12, 13, as well as a sealed pneumatic line 14 connecting the sealed air cavities 15, 16. The entry points for cables 4 and 5 from the energy source 3 in the cavities 15 and 16 are sealed with o-rings 17 and 18. The light source 1 and the transmitter 19, the light source 2 and the transmitter 20 are connected in parallel to the power source 3.

The equipment placed on board the helicopter contains one measuring and two direction finding channels.

The measuring channel consists of a series-connected receiving antenna 23, a fourth narrow-band filter 51, a first phase inverter 52, a first adder 53, the second input of which is connected to the output of a receiving antenna 23, a first band-pass filter 54, a second phase inverter 55, a second adder 56, the second input of which is connected with the output of the adder 53, the second bandpass filter 57, the third phase inverter 58, the third adder 59, the second input is connected to the output of the adder 56, the first mixer 29, the second input of which is connected to the first output of the first the local oscillator 28, the first amplifier 34 of the first intermediate frequency, the fourth adder 64, the fourth multiplier 65, the second input of which is connected to the output of the adder 59, the fifth narrow-band filter 66, the amplitude detector 67, the key 68, the second input of which is connected to the output of the adder 64, the fourth mixer 40, the second input of which is connected to the output of the second local oscillator 39, the amplifier 41 of the second intermediate frequency, the fifth multiplier 70, the second input of which is connected to the output of the low-pass filter 42, the sixth narrow-band filter 71, a simple multiplier 72, the second input of which is connected to the output of the amplifier 41 of the second intermediate frequency, and a low-pass filter 42, the output of which is connected to the second input of the registration unit 43. The sixth mixer 74, the second input of which is connected to the first output of the reference frequency block 73, the fifth amplifier 75 of the first intermediate frequency, the seventh mixer 76, the second input of which is connected to the second output of the reference frequency block 73, and the seventh narrow-band filter 77 are serially connected to the output of the receiving antenna 23 and a second frequency meter 78, the output of which is connected to the third input of the registration unit 43. The seventh multiplier 79, the second input of which is connected to the output of the amplifier 34 of the first intermediate frequency, the eighth narrow-band filter 80 and the third frequency meter 81, the output of which is connected to the fourth input of the registration unit 43, is connected in series to the output of the amplifier 30 of the first intermediate frequency.

To the output of the fourth amplifier 62 of the first intermediate frequency, a phase shifter 82 is connected by -90 °, a fifth adder 83, the second input of which is connected to the output of the first amplifier 34 of the first intermediate frequency, the eighth multiplier 84, the second input of which is connected to the output of the third adder 59, the ninth narrowband a filter, a second amplitude detector 86, a second key 87, the second input of which is connected to the output of the fifth adder 83, the eighth mixer 88, the second input of which is connected to the output of the second local oscillator 39, the second amplifier 89 the second intermediate frequency, the ninth multiplier 90, the second input of which is connected to the output of the second low-pass filter 99, the tenth narrow-band filter, the tenth multiplier 92, the second input of which is connected to the output of the second intermediate-frequency amplifier 89, the second low-pass filter 99 and the second block 103 registration. The ninth mixer 93, the second input of which is connected to the first output of the second block of 96 reference frequencies, the sixth amplifier 94 of the first intermediate frequency, the tenth mixer 95, the second input of which is connected to the second output of the second block of 96 reference frequencies, the eleventh narrowband, is serially connected to the output of the receiving antenna 23 a filter 97 and a fourth frequency meter 98, the output of which is connected to the second input of the second registration unit 103. The eleventh multiplier 100, the second input of which is connected to the output of the intermediate frequency amplifier 30, the twelfth narrow-band filter 101 and the fifth frequency meter 102, the output of which is connected to the third input of the second recording unit 103, the fourth input of which is connected to the output of the first intermediate frequency amplifier 34 the output of the arithmetic unit 69. The outputs of the first 41 and second 89 amplifiers of the second intermediate frequency through a logical element OR 104 are connected to the second inputs of the multipliers 32 and 33.

Each direction finding channel consists of a series-connected receiving antenna 24 (25), a mixer 26 (27), the second input of which is connected to the first output of the first local oscillator 28, an amplifier 30 (31) of the first intermediate frequency, a multiplier 32 (33), the second input of which is connected with the output of the amplifier 41 of the second intermediate frequency, and a narrow-band filter 35 (36). To the output of the first narrow-band filter 35, a third multiplier 37 is connected in series, the second input of which is connected to the output of the second narrow-band filter 36, the third narrow-band filter 44 and the first phase meter 46, the second input of which is connected to the output of the reference generator 49. To the output of the second narrow-band filter 36 are connected in series a delay line 38, a phase detector 45, the second input of which is connected to the output of the narrow-band filter 36, and a second phase meter 47, the second input of which is connected to the output of the reference generator 49. To the output zkopolosnogo filter 44 sequentially connected first frequency meter 50 and the arithmetic unit 69 and register unit 43.

A receiving antenna 23 of the measuring channel is located above the rotor hub of the helicopter, receiving antennas 24 and 25 of direction finding channels are located at the ends of the rotor blades of the helicopter. The engine 48 is kinematically connected with the helicopter propeller and the reference generator 49.

Each transmitter 19 (20) installed in the life jacket contains serially connected master oscillator 82.1, phase manipulator 83.1, the second input of which is connected to the output of modulating code generator 84.1 and power amplifier 85.1.

The system operates as follows.

In the position shown in FIG. 2, 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 depresses the contact 13 from the light source 2 and the transmitter 20, and the lever 10 pushes 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.

In this case, the master oscillator 82 generates a harmonic oscillation (Fig.5, a)

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

where U _c , w _c , φ _c , T _c is the amplitude, carrier frequency, initial phase, and duration of harmonic oscillation, which is supplied to the first input of the phase manipulator 83.

At the second input of the phase manipulator 83, a modulating code M (t) is supplied (Fig. 5, b), which contains the following personal data of a person in distress on water: country, ship, last name, first name, middle name, year of birth and other information. At the output of the phase manipulator 83, a complex signal with phase shift keying (QPSK) is generated (Fig. 5, c)

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

where φ _к (t) = {0, π} is the manipulated component of the phase that displays the law of phase manipulation in accordance with the modulating code M (t), and φ _к (t) = const for кτ _э <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 - the duration and number of chips that make up a signal of duration T _s (T _s = N · τ _e ),

which, after amplification in the power amplifier 85, is emitted by the transmitting antenna 21 as a distress signal.

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 appear at the top. The environmental pressure on the membrane 8 becomes greater than on the membrane 9, the membrane 8 pushes the lever 10, opens the contact 12 s the light source 1 and the transmitter 19. 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. 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 _n and duration T _c 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 rotor of the helicopter can be used to determine the direction of the distress signal to the radiation source (RD radio sensor) using a device whose antennas are located at the ends of the rotor blades.

Received FMN distress signals:

u ₁ (t) = U _c · Cos [(w _c ± Δw) t + φ _к (t) + φ _c ]

where ± Δw is the instability of the carrier frequency of the signal due to various destabilizing factors;

R is the radius of the circle on which the receiving antennas 24 and 25 are located;

Ω = 2πR is the rotation speed of the receiving antennas 24 and 25 around the receiving antenna 23 (rotational speed of the rotor of the helicopter);

α - bearing (azimuth) to the source of the distress signal,

from the outputs of the receiving antennas 23-25 are fed to the first inputs of the mixers 29, 61, 26 and 27, the second inputs of which are the voltage of the local oscillator 28:

u _g1 (t) = U _g1 · Cos (w _g1 t + φ _g1 ),

u ' _g1 (t) = U _g1 · Cos (w _g1 t + φ _g1 + 90 °).

Moreover, the first signal of the mixers 29 and 61 receives the received signal through the adders 53, 56 and 59, in which only one shoulder works. At the output of the mixers, voltages of combination frequencies are formed. Amplifiers 34, 62, 30 and 31 are allocated the voltage of the first intermediate frequency:

u _CR1 (t) = U _CR1 · Cos [(w _CR1 ± Δw) t + φ _k (t) + φ _CR1 ]

u _CR2 (t) = U _CR2 · Cos [(w _CR1 ± Δw) t + φ _к (t) + φ _CR1 -90 °)]

;Where

;

To ₁ - gear ratio of the mixers;

w _p1 = w _c -w _g1 is the first intermediate frequency;

φ _pr1 = φ _s -φ _g1 .

The voltage u _p2 (t) from the output of the amplifier 62 of the first intermediate frequency is supplied to the input of the phase shifter 63 by 90 °, at the output of which a voltage is generated

u _p5 (t) = U _p1 · Cos [(w _p1 ± Δw) t + φ _к (t) + φ _p1 -90 ° + 90 °] =

= U _pp1 · Cos [(w _pp1 ± Δw) t + φ _k (t) + φ _pp1 ].

Voltages u _p1 (t) and u _p5 (t) are supplied to the two inputs of the adder 64, at the output of which the total voltage

u _Σ1 (t) = U _Σ1 · Cos [(w _p1 ± Δw) t + φ _k (t) + φ _p1 ], 0≤t≤T _c ,

where U _Σ1 = 2U _pp1 .

This voltage is supplied to the first input of the multiplier 65, the second input of which receives the received signal U ₁ (t) from the output of the adder 59. A harmonic voltage is generated at the output of the multiplier 65:

u ₄ (t) = U ₄ Cos (w _g1 t + φ _g1 ),

;Where

;

K ₂ is the transmission coefficient of the multiplier.

The tuning frequency w _{n1 of the} narrow-band filter 51 is chosen equal to the first intermediate frequency w _p1

w _n1 = w _np1 .

The tuning frequency w _{n2 of the} narrow-band filter 66 is chosen equal to the frequency of the first local oscillator 28 (Fig.7)

w _H2 = w _g1 .

The tuning frequency w _n3 and the passband Δw _{p1 of the} bandpass filter 54 are chosen equal (Fig. 8)

Δw _p1 = w ₂ -w ₁ ,

where w ₁ , w ₂ are the frequencies of two possible powerful signals, the appearance of which in the frequency band Δw _p1 , located "to the left" of the passband Δw _{p of the} receiver, will lead to the formation of intermodulation interference.

The tuning frequency w _n4 and the passband Δw _{p2 of the} bandpass filter 57 are chosen equal (Fig.9)

Δw _n2 = w ₄ -w ₃ ,

where w ₃ , w ₄ are the frequencies of two possible powerful signals, the appearance of which in the frequency band Δw _p2 , located "to the right" of the passband Δw _{p of the} receiver, will lead to the formation of intermodulation interference.

Since the tuning frequency w _{n2 of the} narrow-band filter 66 is chosen equal to the frequency w _{g1 of the} first local oscillator 28 (w _h2 = w _g1 ), the voltage u ₄ (t) is extracted by the narrow-band filter 66, is detected by the amplitude detector 67 and is supplied to the control input of the key 68, opening him. The key 68 in the initial state is always closed. In this case, the total voltage u _Σ1 (t) through the public key 68 from the output of the adder 64 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 ).

At the output of the mixer 40, a voltage of combination frequencies is generated.

The amplifier 41 is allocated the voltage of the second intermediate frequency (figure 5, g)

u _pr6 (t) = U _pr6 · Cos [(w _p2 ± Δw) t + φ _к (t) + φ _p6 ], 0≤t≤T _c ,

Where

w = w _{pp1 pp2} -w _r2 - second intermediate frequency;

cp = φ _{pr6 pr1} -φ _r2.

which is supplied to the first inputs of the multipliers 70 and 72. The second input of the multiplier 72 is supplied with a reference voltage from the output of the narrow-band filter 71 (Fig. 5, d)

u ₀ (t) = U ₀ · Cos [(w _p2 ± Δw) t + φ _pr6 ], 0≤t≤T _s ,

At the output of the multiplier 72, a voltage is generated

u ₅ (t) = U _n · Cosφ _k (t) + U _n · Cos [2 (w _p2 ± Δw) t + φ _k (t) + φ _pr6 ],

Where

The low-pass filter 42 emits a low-frequency voltage (Fig. 5, e)

u _n (t) = U _n Cosφ _k (t),

which is an analog of the modulating code M (t), is fixed by the registration unit 43 and is supplied to the second input of the multiplier 70. A voltage is generated at the input of the multiplier 70

u ₀ (t) = U ₅ · Cos [(w _p2 ± Δw) t + φ _pr6 ] + U ₅ · Cos [(w _p2 ± Δw) t + 2φ _to (t) + φ _pr6 ] =

= 2U ₅ · Cos [(w _np2 ± Δw) t + φ _np6 ] = U ₀ · Cos [(w _np2 ± Δw) t + φ _np6 ],

where U ₀ = 2U ₅ ,

which is allocated by the narrow-band filter 71 and enters the second input of the multiplier 72.

Multipliers 70, 72, a narrow-band filter 71, and a low-pass filter 42 form a QPSK demodulator that extracts the reference voltage necessary for synchronously detecting the received QPSK signal directly from the received QPSK signal. Moreover, it is free from the phenomenon of “reverse work” inherent in the known devices for forming the reference voltage directly from the received PSK signal (Pistolkors A.A., Kostos D.F., Siforov V.I., Travina G.A. etc. .).

The voltage u _p6 (t) from the output of the amplifier 41 of the second intermediate frequency is simultaneously supplied to the second inputs of the multipliers 32 and 33, the first inputs of which receive the voltage u _pr3 (t) and u _p4 (t) from the outputs of the amplifiers 30 and 31 of the first intermediate frequency, respectively . At the output of multipliers 32 and 33, phase-modulated (FM) voltages are formed:

Where

are allocated narrowband filters 35 and 36 with the tuning frequency w = w _{H5 r2.}

Signs "+" and "-" before the value

correspond to diametrically opposite locations of the antennas 24 and 25 at the ends of the rotor blades of the helicopter relative to the receiving antenna 23 located above the rotor hub of the helicopter.

Consequently, useful information about the bearing α is transferred to the stable frequency w _{g2 of the} second local oscillator 39. Therefore, the instability ± Δw of the carrier frequency of the received FMN 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

which is part of these oscillations and is called the phase modulation index, characterizes the maximum value of the phase deviation of the signals received by the rotating antennas 24 and 25 relative to the phase of the signal received by the fixed antenna 23. The direction finder is more sensitive to the change in angle α, the larger the relative size of the measuring base R / λ . However, with increasing R / λ, the value of the angular coordinate α decreases at which the phase difference exceeds 2π, i.e. ambiguity of reading the angle α occurs.

Therefore, for R / λ> 1/2, the ambiguity of the reference angle α occurs.

The elimination of this ambiguity by reducing the ratio usually does not justify itself, because at the same time, the main advantage of the 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) plane, receiving antennas 24 and 25 are located at the ends of the rotor blades of the helicopter. The mixing of signals from two diametrically opposite receiving antennas 24 and 25 located at the same distance R from the rotor axis of the rotor causes phase modulation, which is identical to the phase modulation obtained using one receiving antenna rotating in a circle whose radius R ₁ is two times more (R ₁ = 2R).

Indeed, the output of the multiplier 37 produces a harmonic voltage

u ₈ (t) = U ₈ · Cos (Ω-α), 0≤t≤T _c ,

Where

with phase modulation index

R ₁ = 2R

which is allocated by a narrow-band filter 44 and fed to the first input of the phasemeter 46, the second input of which is supplied with the voltage of the reference oscillator 50

u _on (t) = U _on CosΩt /

The phasometer 46 provides an accurate but ambiguous measurement of the angular coordinate α.

To eliminate the ambiguity in reading the angle α, it is necessary to reduce the phase modulation index without decreasing the R / λ ratio. This is achieved by using an autocorrelator consisting of a delay line 38 and a phase detector 45, which is equivalent to reducing the phase modulation index to a value

where d ₁ = 2R.

A voltage is generated at the output of the autocorrelator

U ₉ (t) = U ₈ · Cos (Ω-α), 0≤t≤T _s ,

with phase modulation index Δφ _m2 . which is supplied to the first input of the phasemeter 47, the second input of which is supplied with the voltage u _on (t) of the reference generator 50. The phase meter 47 provides a rough but unambiguous measurement of the angle α.

The value of the Doppler frequency shift allows you to determine the radial speed and location of the RD radio sensor.

The minimum distance R ₀ from the radio sensor RD to the helicopter rotor can be determined from the expression

where F _g (t) is the Doppler frequency shift,

U = ΩR,

λ is the wavelength.

The Doppler frequency shift is measured using a frequency meter 50, and the desired range R ₀ is determined in the arithmetic unit 69 and fixed in block 43 registration.

The location of the RD radio sensor (a person in distress on water) is determined by the measured values of α and R ₀ .

The Doppler effect is used to measure the radial velocity of the mutual displacement of a person in distress on water and a helicopter. Its essence lies in the fact that the frequency f _{c of the} received oscillations differs from the frequency f _{0 of the} emitted oscillations if the emitter and the receiver move relative to each other. To this end, the received QPSK signal u ₁ (t) from the output of the receiving antenna 23 is supplied to the first input of the mixer 74, the second input of which is supplied with the voltage of the first reference frequency f ₁ from the first output of the block 73 of the reference frequencies. At the output of the mixer 74, voltages of combination frequencies are generated. The amplifier 75 is allocated the voltage of the first intermediate frequency

f _p1 = f _c -f ₁ = f ₀ + F _g -f ₁ ,

where F _g - Doppler frequency shift due to the mutual movement of the radiation source and the receiver, which is fed to the first input of the mixer 76.

At the second input of the mixer 76, a reference signal is supplied, the frequency of which is determined by the expression

f ₂ = f ₀ -f ₁ + F ₀ ,

where F ₀ is the frequency of the stand, which is introduced to determine the sign of the Doppler shift F _g .

At the output of the mixer 76, oscillations of the following frequency are formed:

f _n = f _np1 -f ₂ = f ₀ + F _g -f ₁ -f ₀ + f ₁ + F ₀ = F _g + F ₀ ,

which are allocated by the narrow-band filter 77. Their frequency is measured by a frequency meter 78 and is fixed by the registration unit 43. The magnitude and sign of the Doppler shift evaluate the magnitude and direction of the radial velocity of the radiation source of the signal. Depending on whether f _n > F ₀ or f _n <F ₀ , the sign of the Doppler shift, and therefore the direction of the radial velocity, is determined.

To measure the criminal velocity of the emitter in azimuth ° α, the voltages u _pp1 (t) and u _p3 (t) from the outputs of amplifiers 34 and 30 of the first frequency are fed to two inputs of the multiplier 79. In this case, the narrow-band filter 80 emits harmonic oscillation at a frequency equal to the difference of the Doppler frequencies in the azimuthal plane

ΔF _g = F _g1 -F _g ± F _g (t).

To measure the angular velocity of the signal source, in addition to the difference in Doppler frequencies, it is necessary to measure the cosine guide in the azimuthal plane:

The indicated Doppler frequency difference is measured by the frequency meter 81 and is recorded by the registration unit 43.

In block 43 registration can be determined by the tangential component of the velocity vector

,

,

and module of the radiator velocity vector

,

,

.which is found as a result of measuring four radio navigation parameters: two coordinates α, R ₀ and two speeds

.

If the FMN distress signal is received on the mirror channel at a frequency w ₃ (Fig. 7), then the amplifiers 34, 62, 30, and 31 distinguish the following voltages of the first intermediate frequency:

u _up7 (t) = U _pr7 · Cos [(w _up1 ± Δw) t + φ _к1 (t) + φ _up7 ]

u _up8 (t) = U _pr8 · Cos [(w _up1 ± Δw) t + φ _к1 (t) + φ _up7 + 90 °]

Where

w _up1 = w _g1 -w ₃ - the first intermediate frequency;

w = φ _{r1 ur7} -φ _3.

The voltage u _up8 (t) from the output of the amplifier 62 of the first intermediate frequency is supplied to the inputs of the phase shifter 63 by + 90 ° and the phase shifter 82 by -90 °, the outputs of which generate voltages:

u _up14 (t) = U _pp8 · Cos [(w _up1 ± Δw) t + φ _к1 (t) + φ _up7 + 90 ° + 90 °] =

= -U for _p8 · Cos [(w _up1 ± Δw) t + φ _к1 (t) + φ _up7 ],

u _up15 (t) = U _pp8 · Cos [(w _up1 ± Δw) t + φ _к1 (t) + φ _up7 + 90 ° -90 °] =

= U _pp8 · Cos [(w _up1 ± Δw) t + φ _к1 (t) + φ _up7 ].

Voltages u _up7 (t) and u _up14 (t) are supplied to two inputs of the adder 83, at the output of which the total voltage is formed

u _Σ3 (t) = U _Σ3 · Cos [(w _up1 ± Δw) t + φ _к1 (t) + φ _up7 ], 0≤t≤T ₃ ,

where U _Σ3 = 2U _pp8 .

This voltage is supplied to the first input of the multiplier 84, to the second input of which the PSK signal is received, received via the mirror channel at a frequency w ₃

u ₃ (t) = U ₃ · Cos [(w ₃ ± Δw) t + φ _к1 (t) + φ ₃ ], 0≤t≤T ₃ .

The output of the multiplier 84 produces a harmonic voltage

u ₁₁ (t) = U ₁₁ Cos (w _g1 t + φ _g1 ),

which is allocated by a narrow-band filter 85 with the tuning frequency w _H2 = w _g1 , is detected by the amplitude filter 86 and is fed to the control input of the key 87, opening it. The key 87 in the initial state is always closed. In this case, the total voltage u _Σ3 (t) from the output of the adder 83 through the public key 87 is supplied to the first input of the mixer 88, the second input of which supplies the voltage of the second local oscillator 39

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

The output of the mixer 88 is formed voltage Raman frequencies. The amplifier 89 is allocated the voltage of the second intermediate frequency

u _up16 (t) = U _p16 · Cos [(w _up2 ± Δw) t + φ _к (t) + φ _up16 ], 0≤t≤T ₃ ,

Where

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

cp = φ _{ur16 ur7} -φ _r2,

which is supplied to the first inputs of the multipliers 90 and 92. The second input of the multiplier 92 is supplied with a reference voltage from the output of the narrow-band filter 91

u ₀₁ (t) = U ₀₁ · Cos [(w _up2 ± Δw) t + φ _up16 ], 0≤t≤T ₃ ,

The output of the multiplier 92 is formed voltage

u ₁₂ (t) = U _н1 · _{Cosφ к1} (t) + U _н1 · Cos [2 (w _up2 ± Δw) t + φ _к1 (t) + φ _up16 ],

Low-pass filter 99 provides low-frequency voltage

U _н1 (t) = U _н1 · _{Cosφ к1} (t),

which is an analog of the modulating code M ₁ (t), is fixed by the registration unit 103 and is supplied to the second input of the multiplier 90. A voltage is generated at the output of the multiplier 90

u ₀₁ (t) = U ₁₂ · Cos [(w _up2 ± Δw) t + φ _up16 ] + U ₁₂ · Cos [(w _up2 ± Δw) t + 2φ _к1 (t) + φ _up16 ] =

= 2U ₁₂ · Cos [(w _up2 ± Δw) t + φ _up16 ] = U ₀₁ · Cos [(w _up2 ± Δw) t + φ _up16 ],

Where

U ₀₁ = 2U ₁₂ ,

which is allocated by the narrow-band filter 91 and enters the second input of the multiplier 92.

The multipliers 90, 92, the narrow-band filter 91 and the low-pass filter 99 form a demodulator of FMN signals received on the mirror channel at a frequency w ₃ , which extracts the reference voltage necessary for synchronous detection of the received FMN signal directly from the received FMN signal itself.

The voltage u _up16 (t) from the output of the amplifier 89 of the second intermediate frequency through the logic element OR 104 is simultaneously supplied to the second inputs of the multipliers 32 and 33, the first inputs of which receive the voltage u _up9 (t) and u _up13 (t) from the outputs of the amplifiers 30 and 31 of the first intermediate frequency, respectively. At the output of multipliers 32 and 33, phase-modulated (FM) voltages are formed:

Where

are allocated narrowband filters 35 and 36 with the tuning frequency w = w _{H5 r2.}

In this case, a harmonic voltage is generated at the output of the multiplier 37

u ₁₅ (t) = U ₁₅ Cos (Ω-α ₁ ), 0≤t≤T ₃ ,

Where

with phase modulation index

which is allocated by a narrow-band filter 44 and fed to the first input of the phasemeter 46, the second input of which is supplied with the voltage of the reference oscillator 50

u _on (t) = U _on CosΩt

The phasometer 46 provides an accurate but ambiguous measurement of the angular coordinate α ₁ .

To eliminate the ambiguity in reading the angle α _1, it is necessary to reduce the phase modulation index without decreasing the R / λ ratio. This is achieved by using an autocorrelator consisting of a delay line 38 and a phase detector 45, which is equivalent to reducing the phase modulation index to a value

where d ₁ = 2R.

A voltage is generated at the output of the autocorrelator

u ₁₆ (t) = U ₁₅ Cos (Ω-α ₁ ), 0≤t≤T ₃ ,

with the phase modulation index Δφ _m3 , which is fed to the first input of the phasemeter 47, the second input of which is supplied with the voltage U _on (t) of the reference oscillator 50. The phase meter 47 provides a rough but unambiguous measurement of the angle α ₁ .

Measuring the radial velocity of the mutual displacement of a person in distress on water and a helicopter uses mixers 93 and 95, an amplifier 94 of the first intermediate frequency, a block 96 of the reference frequencies, a narrow-band filter 97 and a frequency meter 98.

используются перемножитель 100, узкополосный фильтр 101 и измеритель 102 частоты.To measure the angular velocity of the emitter in azimuth

a multiplier 100, a narrow-band filter 101, and a frequency meter 102 are used.

If a false signal (interference) is received on the second combinational channel at a frequency w _k2

u _k2 (t) = U _k2 · Cos (w _k2 t + φ _k2 ), 0≤t≤T _k2 ,

the amplifiers 34 and 62 of the first intermediate frequency are allocated voltage:

u _pp10 (t) = U _pp10 Cos (w _pp1 t + φ _pr10 ),

u _pp11 (t) = U _pp11 Cos (w _pp1 t + φ _pp10 -90 °),

Where

w _p1 = w _k2 -2w _g1 - intermediate frequency;

φ _pr10 = φ _k2 -φ _g1 .

The voltage u _p11 (t) from the output of the amplifier 62 of the first intermediate frequency is supplied to the input of the phase shifter 63 by 90 °, at the output of which a voltage is generated

u _pp12 (t) = U _pp10 · Cos (w _pp t + φ _pr10 -90 ° + 90 °) = U _pp10 · Cos (w _np t + φ _pp10 ).

Voltages u _p10 (t) and u _pp12 (t) are supplied to two inputs of the adder 64, at the output of which a total voltage is generated

u _Σ2 (t) = U _Σ2 · Cos (w _pp1 t + φ _pp1 ), 0≤t≤T _k2 ,

where U _Σ2 = 2U _pp10 .

This voltage is supplied to the first input of the multiplier 65, the second input of which receives the received signal u _k2 (t). The output of the multiplier 65 produces a voltage

u ₁₀ (t) = U ₁₀ · Cos (w _g1 t + φ _g1 ), 0≤t≤T _k2 ,

Where

which does not fall into the passband of the narrow-band filter 66. The key 68 does not open and the false signal (interference) received on the second combinational channel at a frequency w _k2 is suppressed. In this case, an “inner ring” is used, consisting of a multiplier 65, a narrow-band filter 66, an amplitude detector 67 and a key 68, and implementing the narrow-band filtering method.

If a false signal (interference) is received on the direct channel at the first intermediate frequency

_prosp u (t) = U _prosp · Cos (w t + φ _{pp1 etc.), etc.} 0≤t≤T,

then from the output of the receiving antenna 23, it enters the first input of the adder 53, is allocated by a narrow-band filter 51 tuned to the first intermediate frequency w _pr1 , and is inverted in phase by 180 ° in the phase inverter 52

u ' _pp (t) = - U _pp · Cos (w _pp1 t + φ _pr ), 0≤t≤T _pr .

The _voltages u _pp (t) and u ' _pp (t) supplied to the two inputs of the adder 53 are compensated at its output.

Therefore, a false signal (interference) received through the direct channel at a frequency w _pr1 is suppressed by a filter plug consisting of a narrow-band filter 51, a phase inverter 52 and an adder 53 and implementing a phase compensation method.

If two powerful signals (interference) at frequencies w ₁ and w ₂ or several powerful signals (interference) appear simultaneously in the frequency band Δw _p1 "to the left" of the passband Δw _{p of the} receiver, capable of generating intermodulation interference, then they are fed to the first input of the adder 56, are distinguished by a band-pass filter 54, phase inverted by 180 ° by the phase inverter 55 and compensated in the adder 56 (Fig. 8.).

Therefore, false signals (interference) received in the frequency band Δw _p1 and generating intermodulation interference are suppressed by a filter plug consisting of a bandpass filter 54, a phase inverter 55 and an adder 56 and implementing a phase compensation method.

If two powerful false signals (interference) at frequencies w ₃ and w ₄ or several powerful signals (interference) appear simultaneously in the frequency band Δw _p2 "to the right" of the passband Δw _{p of the} receiver, capable of generating intermodulation interference, then they are fed to the first input the adder 59, are allocated by the band-pass filter 57, are inverted by 180 ° phase in phase inverter 58 and compensated in the adder 59 (Fig. 9.).

Consequently, false signals (interference) received in the frequency band Δw _p2 and generating intermodulation interference are suppressed by a filter plug consisting of a bandpass filter 57, a phase inverter 58 and an adder 59 and implementing a phase compensation method.

The on-board equipment installed on board the helicopter is invariant to the type of modulation and instability of the carrier frequency ± Δw of the received radio signals, since direction finding of the distress signal radiation source is carried out at a stable frequency w _{g2 of the} second local oscillator 39.

Thus, the proposed system in comparison with the prototype and other technical solutions for a similar purpose provides a doubled range of operating frequencies, the frequency range of the signal search without expanding the frequency range of the local oscillator. This is achieved through the use of complex QPSK signals received on the mirror channel at a frequency of w ₃ . Moreover, the conversion of complex QPSK signals received on the mirror channel at a frequency w ₃ occurs with the same conversion coefficient K _pr as on the main reception channel at a frequency w _c .

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 its back area, two miniature transmitters with transmitting antennas , 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 interconnected sealed containers, each of which is divided from the environment by a membrane, while one of the sealed containers is located in the chest area of the life jacket, and the other in its back area, the membrane of each container is connected to the circuit breaker of the corresponding light source by a lever, and both light sources and transmitters through the breakers connected to a current source in parallel, and equipment installed on board the helicopter and consisting of one measuring and two direction finding channels, while the measuring channel consists of consistently included receiving antenna, fourth narrow-band filter, first phase inverter, first adder, the second input of which is connected to the output of the receiving antenna, first bandpass filter, second phase inverter, second adder, the second input of which is connected to the output of the first adder, second bandpass filter, third phase inverter, the third adder, the second input of which is connected to the output of the second adder, the first mixer, the second input of which is connected to the first output of the first local oscillator, the first amplifier the first intermediate frequency, the fourth adder, the fourth multiplier, the second input of which is connected to the output of the third adder, the fifth narrow-band filter, the first amplitude detector, the first key, the second input of which is connected to the output of the fourth adder, the fourth mixer, the second input of which is connected to the output of the second local oscillator , and the first amplifier of the second intermediate frequency, while the first phase shifter 90 °, the fifth mixer, the second input are serially connected to the second output of the first local oscillator which is connected to the output of the third adder, the fourth amplifier of the first intermediate frequency and the second phase shifter 90 °, the output of which is connected to the second input of the fourth adder, each direction finding channel consists of a series-connected receiving antenna, a mixer, the second input of which is connected to the first output of the first local oscillator , an amplifier of the first intermediate frequency, a multiplier and a narrow-band filter, while the third multiplier, the second is connected in series to the output of the first narrow-band filter the path of which is connected to the output of the second narrow-band filter, the third narrow-band filter and the first phase meter, a delay line, a phase detector, the second input of which is connected to the output of the second narrow-band filter, and the second phase meter, the second inputs of the phase meters are connected to the output of the reference one, to the output of the second narrow-band filter generator, the first frequency meter, the arithmetic unit and the first registration unit, the receiving antenna of the measuring antenna are connected in series to the output of the third narrow-band filter the channel is located above the rotor hub of the helicopter, 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, the fifth multiplier is connected to the output of the first amplifier of the second intermediate frequency, the second input of which is connected to the output of the first lower filter frequencies, the sixth narrow-band filter, the sixth multiplier, the second input of which is connected to the output of the first amplifier of the second intermediate frequency, and the first a low-pass filter, the output of which is connected to the second input of the first recording unit, the sixth mixer is connected in series to the output of the receiving antenna of the measuring channel, the second input of which is connected to the first output of the first block of reference frequencies, the fifth amplifier of the first intermediate frequency, the seventh mixer, the second input of which is connected with the second output of the first block of reference frequencies, the seventh narrow-band filter and a second frequency meter, the output of which is connected to the third input of the first block of registration, to the output a seventh multiplier is connected in series to the amplifier of the first intermediate frequency of the first direction-finding channel, the second input of which is connected to the output of the amplifier of the first intermediate frequency of the measuring channel, the eighth narrow-band filter and the third frequency meter, the output of which is connected to the fourth input of the first recording unit, each transmitter installed in the rescue the vest, contains a serially connected master oscillator, a phase manipulator, the second input of which is connected to the generator output and a modulating code, and a power amplifier, characterized in that it is equipped with a -90 ° phase shifter, fifth adder, eighth, ninth, tenth and eleventh multipliers, ninth, tenth, eleventh and twelfth narrow-band filters, second amplitude detector, second key, eighth , the ninth and tenth mixers, the second amplifier of the second intermediate frequency, the second low-pass filter, the fourth and fifth frequency meters, the second reference frequency unit, the second recording unit and the OR logic element, when than the phase shifter -90 °, the fifth adder, the second input of which is connected to the output of the first amplifier of the first intermediate frequency, the eighth multiplier, the second input of which is connected to the output of the third adder, the ninth narrow-band filter, the second amplitude detector , the second key, the second input of which is connected to the output of the fifth adder, the eighth mixer, the second input of which is connected to the output of the second local oscillator, the second amplifier is the second intermediate full-time frequency, the ninth multiplier, the second input of which is connected to the output of the second low-pass filter, the tenth narrow-band filter, the tenth multiplier, the second input of which is connected to the output of the second amplifier of the second intermediate frequency, the second low-pass filter and the second recording unit, the second input of which is connected to the output of the arithmetic unit, the ninth mixer is connected in series to the output of the receiving antenna of the measuring channel, the second input of which is connected to the first output of the second reference unit often t, the sixth amplifier of the first intermediate frequency, the tenth mixer, the second input of which is connected to the second output of the second block of reference frequencies, the eleventh narrow-band filter and the fourth frequency meter, the output of which is connected to the third input of the second recording unit, to the output of the first amplifier of the first intermediate frequency of the measuring channel the eleventh multiplier is connected in series, the second input of which is connected to the output of the second amplifier of the first intermediate frequency of the first direction-finding channel, d the twelfth narrow-band filter and the fifth frequency meter, the output of which is connected to the fourth input of the second recording unit, the outputs of the first and second amplifiers of the second intermediate frequency are connected via the OR logic element to the second inputs of direction finding multipliers.

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