RU2363614C1 - System to detect person in marine disaster - Google Patents

Abstract

FIELD: instrument making.

SUBSTANCE: invention relates to rescue means and can be used for detection of person in marine disaster and locating him. The system comprises life-saving jacket and receiver installed at the control station. Life-saving jacket comprises light sources (1) and (2), power source (3), cables (4) and (5), cartridges (6) and (7), membranes (8) and (9), levers (10) and (11), terminals (12) and (13), pneumatic line (14), air spaces (15) and (16), seal rings (17) and (18), transmitters (19) and (20) with transmitting antennas (21) and (22). Transmitter comprises measuring and four direction-finding channels that include receiving antennas, HF amplifiers, local oscillators, mixer, IF amplifier, amplitude detector, delay line, three computation units, integration unit, division unit, reference voltage shaping unit, comparator unit, computation unit, switch, multiplication units, narrow-band filters, phase meters, registration units and adders.

EFFECT: increased range of unambiguous measurement of alarm signal source angular coordinates at minor length of rough measurement bases.

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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.

Known systems for detecting a person in distress on water (ed. Certificate of the USSR No. 431.063, 637.298, 765.113, 988.655, 1.348.819, 1.505.840, 1.588.636, 1.615.054, 1.643.325, 1.664.653; RF patents No. 2.000.995, 2.009.956, 2.038.259, 2.043.259, 2.051.838, 2.193.990; US patents No. 3.621.501, 4.889.511; UK patent No. 1.145.051; Danish patent No. 1.103.118; Dikarev V.I. Safety, protection and salvation of a person.St. Petersburg: Nauka i Tekhnika, 2007. - 574 p. And others).

Of the known systems closest to the proposed is the "System for the detection of a person in distress on the water" (RF patent No. 2.193.990, B63C 9/20, 2000), which is selected as a prototype.

The specified system contains a life vest, worn per person and equipped with two light sources and two miniature transmitters that provide detection of a person in distress on water in daylight and in bad weather over long distances. In this case, to determine the source of distress signal radiation, the phase method is used using five isotropic receiving antennas arranged in the form of a geometric right angle. Two report scales are used in each plane: large - accurate, but ambiguous and small - rough, but unambiguous.

However, in some cases, with large ranges of measuring the angular coordinates of the distress signal source, the rough measuring bases d can be so small that it is physically impossible to place two receiving antennas on them. In such cases, the formation of rough scales is possible by an indirect method. To do this, in each plane two measuring unequal bases d ₁ and d ₂ , d ₅ and d ₆ are selected (Fig. 4), and phase shifts Δφ ₁ , and Δφ ₂ , Δφ ₃ and Δφ ₄ are measured on each of them. Measuring the difference of phase differences.

Δφ _p1 = Δφ ₁ -Δφ ₂ and Δφ _p2 = Δφ ₃ -Δφ ₄

equivalent to measuring phase shifts at bases whose length

d ₃ = d ₁ -d ₂ , d ₇ = d ₅ -d ₆ .

Thus, choosing the differences of the bases d ₃ and d ₇ small enough, it is possible to ensure the formation of the corresponding rough measuring bases.

It should be noted that the total phase shifts

Δφ _∑1 = Δφ ₁ + Δφ ₂ and Δφ _∑2 = Δφ ₃ + Δφ ₄

can be used to form measurements equivalent to measuring the phase difference on the measuring bases d ₄ and d ₈ , the length of which is equal to the sum of the two source bases:

d ₄ = d ₁ + d ₂ and d ₈ = d ₅ + d ₆ .

An object of the invention is to increase the range of unambiguous measurement of the angular coordinates of the distress signal source with a small length of rough measuring bases.

The problem is solved in that a system for detecting a person in distress on water, including, in accordance with the closest analogue, a life jacket, dressed on 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 spinal region, a current source, two circuit breakers, 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 thoracic region of the spa body vest, and the other in its back area, the membrane of each tank is connected to the circuit breaker of the corresponding light source by a lever, and both light sources are connected through parallel circuit breakers to the current source, 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, and the receiver installed at the control point and containing a measuring channel, consisting of a receiver connected in series an antenna, a high-frequency amplifier, a mixer, the second input of which is connected to the output of the local oscillator, an intermediate-frequency amplifier, an amplitude detector, a delay line, the first subtraction unit, the second input of which is connected to the output of the amplitude detector, integration unit, division unit, the second input of which is connected to the output of the first subtraction unit, the comparison unit, the second input of which is connected to the output of the unit for generating the reference voltage, the computing unit and the registration unit, and four direction finding channels, one of which consists of a series-connected receiving antenna, a high-frequency amplifier, a multiplier, the second input of which is connected via a key to the outputs of an intermediate-frequency amplifier and a comparison unit, a narrow-band filter and a phase meter, the second input of which is connected to the local oscillator output, differs from the closest analogue in that that it is equipped with a second and third subtraction units and two adders, and the second subtraction unit is connected to the output of the first phase meter, the second input of which is connected to the output of the second phase meter, and the output is connected to the second input of the registration unit, the first adder is connected to the output of the first phase meter, the second input of which is connected to the output of the second phase meter, and the output is connected to the third input of the registration unit, the third subtraction unit is connected to the output of the third phase meter, the second input of which is connected to the output the fourth phase meter, and the output is connected to the fourth input of the recording unit, the second adder is connected to the output of the third phase meter, the second input of which is connected to the output of the fourth phase meter, and the output is connected to the fifth entry registration unit, the receiving antennas are arranged in the form of an asymmetric geometrical cross, the intersection of which is placed a receiving antenna of the measuring channel which is common to the reception antennas direction finding channels disposed in the azimuth and elevation planes, thereby forming two measurement bases in each plane d ₃ and d ₄ , d ₇ and d ₈ equal to d ₃ = d ₁ -d ₂ , d ₄ = d ₁ + d ₂ , d ₇ = d ₅ -d ₆ , where d ₁ , d ₂ are measuring unequal bases in the azimuthal plane, d ₅ , d ₆ - measuring unequal bases in the elevation plane, with smaller bases d ₃ and d ₇ formed rough, but unequivocal scales of reference angles, and large bases of d ₄ and d ₈ formed accurate, but ambiguous scales of reference angles.

The essence of the invention lies in the fact that a life jacket dressed in a person in distress on the water is equipped with a radio emitter, and at the control point, at least two consecutive measurements of the intensity of the received signal are periodically determined, the difference signal of two consecutive measurements is determined, the difference signal is integrated, the difference signal is divided signal to the integrated differential signal, and the obtained value is compared with a predetermined threshold value. This allows you to compensate for natural interference (thunderstorm activity, disturbance in the ionosphere, etc.) and artificial (industrial installations, radio communications, etc.) origin and to detect a radio emitter signal at a certain frequency.

To determine the coordinates of the radiator, the phase direction finding method is used, which is characterized by a contradiction between the accuracy and uniqueness of determining the coordinates of the distress signal source. In order to eliminate this contradiction, two reference scales are used in each plane: large - accurate, but ambiguous and small - rough, but unequivocal.

Figure 1 schematically shows a life jacket with light sources 1, 2 and transmitters 19, 20 with transmitting antennas 21, 22, dressed in person; figure 2 is the same section. The structural diagram of the receiver, placed at the control point, is shown in Fig.3. The relative position of the receiving antennas is shown in Fig.4.

The system contains a life vest with light sources 1 and 2, transmitters 19 and 20 with transmitting antennas 21 and 22, respectively, and a receiver installed at the control point.

The life jacket, in addition, consists of an energy source 3, cables 4 and 5 for supplying energy to light sources 1, 2 and transmitters 19, 20, cartridges 6 and 7, membranes 8, 9 and associated levers 1 and 11 with contacts 12 and 13, as well as a sealed pneumatic line 14 connecting the sealed air cavities 15 and 16. The entry points of 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 is connected in parallel to the power source 3.

The receiver installed at the control point contains a measuring channel and four direction finding channels. The measuring channel consists of a series-connected receiving antenna 23, a high-frequency amplifier 28, a mixer 34, the second input of which is connected to the output of the local oscillator 33, an intermediate frequency amplifier 35, an amplitude detector 36, a delay line 37, and a subtraction unit 38, the second input of which is connected to the output amplitude detector 36, integration unit 39, division unit 40, the second input of which is connected to the output of the subtraction unit 38, comparison unit 42, the second input of which is connected to the output of the reference voltage generating unit 41, digital block 43 and block 57 registration.

Each direction finding channel consists of a series-connected receiving antenna 24 (25, 26, 27), a high-frequency amplifier 29 (30, 31, 32), a multiplier 45 (46, 47, 48), the second input of which is connected through the key 44 to the outputs of the amplifier 35 of the intermediate frequency, and a comparison unit 42, a narrow-band filter 49 (50, 51, 52) and a phase meter 53 (54, 55, 56), the second input of which is connected to the output of the local oscillator 33, and the output is connected to the corresponding input of the registration unit 57 through the corresponding a subtraction block 58 (60) or an adder 59 (61).

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 depressed state. Accordingly, the lever 11 depresses the contact 13 from the light source 2 and the transmitter 22, 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 .

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 _n and a duration T _c at a certain frequency f _c , which is allocated specifically for transmitting a distress signal and is not involved in transmitting other information.

The receiver is located at a control point that can be placed on land, on ships of various purposes, including search and rescue ships in distress on water, as well as on aircraft (helicopters, airplanes and spacecraft).

Receiving antennas 23-27, raised above the surface of the water, for example, using an aircraft and located in the form of an asymmetric geometric cross (figure 4), receive a distress signal:

where V _c , w _c T _c , φ ₁ -φ ₅ is the amplitude, frequency, duration and initial phases of distress signals received by antennas 23-27;

± Δw is the instability of the carrier frequency of the distress signal due to various destabilizing factors.

The distress signal is recorded by receiving antennas 23-27. The registered receiving signal U ₁ (t) from the output of the receiving antenna 23 through the high-frequency amplifier 28 is supplied to the first input of the mixer 34, the second input of which supplies the voltage of the local oscillator 33, the frequency w _{g of} which is stabilized, for example, by quartz

U _g (t) = V _g cos (w _g t + φ _g ).

At the output of the mixer 34, an intermediate (differential) frequency voltage is generated

Where

To ₁ - gear ratio of the mixer;

w _CR = w _with -w _g - intermediate frequency;

φ _CR = φ _s -φ _g .

The distress signal intensity is measured by an electromagnetic field strength meter, which uses an amplitude detector 36. At each observation point, at least two consecutive measurements of the electromagnetic field strength are made. Then, the operation of subtracting two consecutive measurements is performed. For this, the signal corresponding to the previous measurement is delayed by the delay line 37 until it is compared with the subsequent signal in block 38 by subtraction. The operations of integrating the difference signal and dividing the difference signal by the integrated difference signal are performed in blocks 39 and 40, respectively. In block 42, the normalized signal is compared with the threshold value of the signal set by block 41. In the computing block 43, the measurement results are processed.

The above operations allow you to compensate for natural (lightning activity, disturbance in the ionosphere, etc.) and artificial (industrial installations, radio communications, etc.) origin and detect a distress signal at a specific frequency w _s .

The signal from the output of the comparison unit 42 simultaneously enters the control input of the key 44, opening it. In the initial state, the key 44 is always closed.

In this case, the signals U ₂ (t) -U ₅ (t) received by the antennas 24-27 through high-frequency amplifiers 29-32 are fed to the first inputs of the multipliers 45-48, respectively, the second inputs of which are supplied with voltage U _pr (t) s the output of the intermediate frequency amplifier 35 through the public key 44.

The outputs of the multipliers 45-48 form the following harmonic oscillations:

;

;

Where

K ₂ - transmission coefficient of the multipliers;

α, β - angular coordinates (azimuth and elevation) of the distress signal source;

λ is the wavelength;

d ₁ , d ₂ , d ₅ , d ₆ - measuring bases formed by antennas 24 and 23, 23 and 25, 26 and 23, 23 and 27, respectively,

which are allocated by narrow-band filters 49-52 and fed to the first inputs of the phase meters 53-56, respectively.

The second inputs of the phase meters 53-56 are supplied with the voltage U _g (t) of the local oscillator 33. Phasometers 53-56 measure the phase shifts Δφ ₁ -Δφ ₄ , which are fed to the inputs of the subtraction units 58 and 60 and the adders 59 and 61.

Measurement of the difference of the phase differences at the output of the subtraction blocks 58 and 60:

Δφ _p1 = Δφ ₁ -Δφ ₂ and Δφ _p2 = Δφ ₃ -Δφ ₄

equivalent to measuring phase shifts on measuring bases, the length of which is determined by the difference:

d ₃ = d ₁ -d ₂ , d ₇ = d ₅ -d ₆ .

Thus, choosing the differences of the bases d ₃ and d ₇ small enough, it is possible to ensure the formation of the corresponding measuring bases.

Total phase shifts

Δφ _∑1 = Δφ ₁ + Δφ ₂ and Δφ _∑2 = Δφ ₃ + Δφ ₄ ,

obtained at the output of the adders 59 and 61, are used to form measurements equivalent to measuring the phase difference on the measuring bases d ₄ and d ₈ , the length of which is equal to the sum of the source bases:

d ₄ = d ₁ + d ₂ , d ₈ = d ₅ + d ₆ .

In this case, the following inequalities are fulfilled between the formed measuring bases:

The phase shifts Δφ _p1 , Δφ _p2 , Δφ _∑1 , Δφ _∑2 are recorded by the registration unit 57.

Knowing the flight altitude h of the aircraft and measuring the angular coordinates, it is possible to accurately and unambiguously determine the coordinates of the radiation source of the exposure signal (a person in distress on water).

The receiver is invariant to the instability of the carrier frequency of the received signals, since the direction finding of the distress signal source is carried out at a stable oscillator frequency w _g 33. The receiver is also invariant to the form of modulation of the received signals if the distress signals have modulation (manipulation) of one of the parameters.

In addition, through the use of fixed isotropic receiving antennas, the technical implementation of the receiver on board aircraft and objects is greatly simplified.

Thus, the proposed system in comparison with the prototype provides an increase in the range of unambiguous measurement of the angular coordinates of the source of the distress signal (a person in distress on water) with a small length of rough measuring bases. This is achieved by forming coarse scales by the indirect method and by positioning the receiving antennas in the form of an asymmetric geometric cross, at the intersection of which there is a receiving antenna of the measuring channel common to receiving antennas located in the azimuthal and elevation planes.

Claims (1)

A system for detecting a person in distress on the water, including a life jacket dressed on 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 interconnected 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 area, the membrane of each container connected to the circuit breaker of the corresponding light source by means of a lever, and two light sources through the switches are connected in parallel with the current source, 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, and a receiver installed at the control point and containing a measuring channel, consisting of a series-connected receiving antenna, a high-frequency amplifier, a mixer, the second input of which is connected with the output of the local oscillator, the intermediate frequency amplifier, the amplitude detector, the delay line, the first subtraction unit, the second input of which is connected to the output of the amplitude detector, the integration unit, the division unit, the second input of which is connected to the output of the first subtraction unit, the comparison unit, the second input of which is connected with the output of the unit for generating the reference voltage, the computing unit and the registration unit, and four direction finding channels, each of which consists of a series-connected receiving antenna, an amplifier a high frequency amplifier, a multiplier, the second input of which is connected via a key to the output of the intermediate frequency amplifier and the comparison unit, a narrow-band filter and a phase meter, the second input of which is connected to the local oscillator output, characterized in that it is equipped with a second and third subtraction units and two adders, the second subtraction unit is connected to the output of the first phase meter, the second input of which is connected to the output of the second phase meter, and the output is connected to the second input of the registration unit, the first is connected to the output of the first phase meter umator, the second input of which is connected to the output of the second phase meter, and the output to the third input of the registration unit, the third subtraction unit is connected to the output of the third phase meter, the second input of which is connected to the output of the fourth phase meter, and the output is connected to the fourth input of the registration unit, to the output of the third a second adder is connected to the phase meter, the second input of which is connected to the output of the fourth phase meter, and the output is connected to the fifth input of the recording unit, the receiving antennas are placed in the form of an asymmetric geometric cross, in section of which is placed a receiving antenna of the measuring channel which is common to the reception antennas direction finding channels disposed in the azimuth and elevation planes, thereby forming in each plane two measuring bases d ₃ and d _4, d ₇ and d ₈ equal to d ₃ = d ₁ - d ₂ , d ₄ = d ₁ + d ₂ , d ₇ = d ₅ -d ₆ , d ₈ = d ₅ + d ₆ , where d ₁ , d ₂ are measuring unequal bases in the azimuthal plane, d ₅ , d ₆ - measuring unequal base elevation plane while the smaller bases d ₃ and d ₇ are formed rough but unambiguous reference angle scale and large bases d ₄ and d ₈ are formed accurate But ambiguous scale the angles.

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