RU2369418C1 - Method for detection of dumped bioobjects or their remains location and device for their realisation - Google Patents

Abstract

FIELD: mining.

SUBSTANCE: device that realises suggested method, comprises scanning and transceiving blocks. Scanning block comprises driving oscillator, power amplifier, circulator, horn transceiving antenna, high frequency amplifier, phase detector, computer, heterodyne, mixer, intermediate frequency amplifier, the first, second and third multipliers, the first and second band filters, generator of sawtooth voltage, frequency modulator, narrow band filter and frequency metre. Transceiving block comprises crystal, microstrip antenna, two comb systems of electrodes, bus bars and a set of reflectors.

EFFECT: higher validity of dumped bioobjects and their remains detection by means of automatic measurement of distance from scanning block to transceivers located on dumped bioobjects or their remains.

2 cl, 4 dwg

Description

The proposed method and device relates to the field of search and rescue operations and can be used to search for bombarded bioobjects or their remains in earthquake areas, as well as in tourism and mountaineering when searching for bioobjects bombarded with, for example, avalanches or mountain landslides.

Known methods and devices for detecting the location of living creatures that have fallen into rubble (RF patents No. 2116099, 2248235, 2306159; EP application No. 0075199; VK Vinokurov and others. Safety in mountaineering. - M .: 1983, p.136- 137; Dikarev V.I. Safety, protection and salvation of a person. - St. Petersburg: 2007, p. 61-78, etc.).

Of the known methods and devices closest to the proposed are "A method for detecting the location of buried biological objects or their remains and a device for its implementation" (RF patent No. 2306159, A62B 37/00, 2005), which are selected as prototypes.

The known method and device provide an increase in the sensitivity and dynamic range of the receiver of the scanning unit, as well as an increase in the reading range of information about the biological object by constructing the receiver of the scanning unit in a superheterodyne circuit.

However, the known method and device do not automatically determine the distance between the scanning unit and the transceivers located on the bombarded bioobjects or their remains, which reduces the reliability of finding the location of the bombarded bioobjects or their remains.

An object of the invention is to increase the reliability of detecting the location of bombarded biological objects or their remains by automatically determining the distance from the scanning unit to transceivers located on filled biological objects or their remains.

The problem is solved in that a method for detecting the location of buried biological objects or their remains, consisting, in accordance with the closest analogue, of preliminary placing on a biological object belonging to the risk group a low-power transceiver, which is used as a piezocrystal with an aluminum counter-deposited on its surface a pin transducer associated with a microstrip antenna and a set of reflectors, irradiation with a scanning unit of the filled area, above the surface of the cat A biological object or its remains can be located by a directed electromagnetic signal, receive it on a buried biological object or its remains, transform into an acoustic wave, ensure its propagation over the surface of the piezocrystal and back reflection, transform the reflected acoustic wave again into an electromagnetic signal, the internal structure of which corresponds to the structure interdigital transducer, re-emitting it to air, receiving by the scanning unit, amplification in amplitude, frequency conversion using the local oscillator voltage, isolating the intermediate frequency voltage, isolating the electromagnetic signal with phase shift keying at the local oscillator frequency, performing its synchronous detection using the local oscillator voltage as the reference voltage, registering the selected analog of the modulating code corresponding to the structure of the interdigital converter, analyzing it, and determining the ownership the filled biological object or its remains differs from the closest analogue in that they are directed before the irradiation, the electromagnetic signal is modulated in frequency according to a sawtooth law, the reflected acoustic wave is converted into an electromagnetic complex signal with combined linear frequency modulation and phase shift keying, the amplified electromagnetic complex signal with combined linear frequency modulation and phase shift keying is converted in frequency using the local oscillator voltage , multiply the voltage of the intermediate frequency with the voltage of the master oscillator, modulated by h On the basis of a sawtooth law, an amplified electromagnetic complex signal with a combined linear frequency modulation and phase shift keying with an isolated analogue of the modulating code is multiplied, an electromagnetic signal with a linear frequency modulation is isolated, it is multiplied with the voltage of the master oscillator, frequency-modulated according to a sawtooth law, the voltage is isolated beats, measure the frequency of the beats and determine the distance from the scanning unit to the transceiver located on the covered bi object or its remains.

The problem is solved in that a device for detecting buried bioobjects or their remains, containing, in accordance with the closest analogue, a transceiver associated with the antenna and located on a bioobject belonging to a risk group, a scanning unit consisting of a master oscillator and a power amplifier connected in series , a circulator, the input-output of which is connected to a horn transceiver antenna, a high-frequency amplifier, a mixer, the second input of which is connected to the output of the local oscillator, an amplifier the original frequency, the first multiplier, the first bandpass filter, the phase detector, the second input of which is connected to the output of the local oscillator, and the computer, while the transceiver unit is made in the form of a piezocrystal with an aluminum thin-film interdigital transducer deposited on its surface connected to a microstrip antenna, and a set of reflectors, the interdigital transducer contains two comb systems of electrodes, the electrodes of each of the combs are connected to each other by buses connected to a microstrip th antenna differs from the closest analogue in that it is equipped with a sawtooth voltage generator, a frequency modulator, a second and third multiplier, a second bandpass filter, a narrowband filter and a frequency meter, and a frequency modulator connected to the output of the master oscillator, the second input of which is connected to the output of the sawtooth generator voltage, and the output is connected to the input of the power amplifier, the second multiplier is connected in series to the output of the high-frequency amplifier, the second input of which is connected to the output house phase detector, a second bandpass filter, a third multiplier, a second input coupled to an output of the frequency modulator, a narrowband filter and a frequency counter, a second input of the first multiplier connected to the output of the frequency modulator.

A structural diagram of a device that implements the proposed method is shown in FIGS. 1 and 2. Frequency-time diagrams explaining the principle of operation of the method and device for detecting the location of buried biological objects or their remains are shown in FIGS. 3 and 4.

A device that implements the proposed method contains a scanning unit and a transceiver unit.

The scanning unit contains a serially connected master oscillator 1, a frequency modulator 20, the second input of which is connected to the output of a sawtooth voltage generator 19, a power amplifier 2, a circulator 3, the input-output of which is connected to a horn transceiver antenna 4, a high-frequency amplifier 5, a mixer 15, the second input of which is connected to the output of the local oscillator 14, the intermediate frequency amplifier 16, the first multiplier 17, the second input of which is connected to the output of the frequency modulator 20, the first bandpass filter 18, phase detector 6 the second input of which is connected to the output of the local oscillator 14, and the computer 7, connected in series to the output of the high-frequency amplifier 5, the second multiplier 21, the second input of which is connected to the output of the phase detector 6, the second bandpass filter 22, the third multiplier 23, the second input of which is connected to the output of the frequency modulator 20, a narrow-band filter 24 and a frequency counter 25.

The transceiver unit is made in the form of a piezocrystal 8 with an aluminum thin-film interdigital transducer deposited on its surface connected to a microstrip antenna 9 and a set of reflectors 13.

The interdigital transducer of surface acoustic waves (SAW) contains two comb systems of electrodes 10, buses 11 and 12, which connect the electrodes of each of the combs to each other. Tires 11 and 12, in turn, are connected to the microstrip antenna 9.

The proposed method is implemented as follows.

The master oscillator 1 forms a high-frequency oscillation

U _c (t) = ν _c Cos (ω _c t + φ _c ), 0≤t≤T _C ,

where ν _c , ω _c , φ _c ; T _c is the amplitude, carrier frequency, the initial phase and the duration of the high-frequency oscillation, which is supplied to the first input of the frequency modulator 20, the second input of which is supplied with the modulating voltage from the output of the sawtooth voltage generator 19. The output of the frequency modulator 20 produces a signal with linear frequency modulation (LFM)

U ₁ (t) = ν _s Cos (ω _c t + πγt ² + φ _c ), 0≤t≤T _M ,

where γ = Δω _d / T _M is the rate of change of the signal frequency;

Δω _d - frequency deviation;

T _M - period of modulation (figure 3),

which is amplified by power in a power amplifier 2

U ₂ (t) = ν ₂ Cos (ω _with t + πγt ² + φ _c ), 0≤t≤T _M ,

and through the circulator 3 enters the horn transceiver antenna 4 and is broadcast. With the help of a horn antenna 4, a bombarded area is sequentially irradiated, where the biological object or its remains are supposedly located.

An electromagnetic signal U ₂ (t) with linear frequency modulation is received by a microstrip antenna 9 of a transceiver located on a biological object or its remains. The latter is a piezocrystal 8 with an aluminum thin-film interdigital SAW transducer deposited on its surface, which consists of two comb systems of electrodes 10 deposited on the surface of the piezocrystal 8. The electrodes of each of the combs are connected to each other by buses 11 and 12. Tires 11 and 12 , in turn, are associated with a microstrip antenna 9.

The received signal U ₂ (t) with linear frequency modulation is converted by an interdigital transducer into an acoustic wave that propagates along the surface of the piezoelectric crystal 8, is reflected from the reflectors 13, and again converted into an electromagnetic complex signal with combined linear frequency modulation and phase shift keying (LFM-FMN )

U ₃ (t) = ν ₃ · Cos [ω _c t + πγt ² + φ _к (t) + φ _c ], 0≤t≤T _C ,

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) (Fig. 4, a), and φ _к (t) = const at k · τ _e <t <(k + 1) · τ _e and can change abruptly at t = k · τ _e , i.e. at the borders between elementary premises (k = 1, 2, ..., N-1);

τ _e , N - the duration and number of chips that make up the signal duration

T _C (T _C = N · τ _e ).

In this case, the internal structure of the generated LFM-QPSK signal of the modulating code M (t) is determined by the topology of the interdigital transducer, has an individual character and contains all the necessary unique information about the filled bioobject or its remains, for example, surname, name, middle name, year of birth, etc. .P.

The generated LFM-QPSK signal U ₃ (t) is radiated by the microstrip antenna 9, received by the antenna of the scanning unit 4, and fed through the circulator 3 and the high-frequency amplifier 5 to the first input of the mixer 15

₄ U (t) = ν _{4 · Cos [ω c (t-} τ ₃₎ + πγ (t-τ ₃₎ ² + φ _a (t-τ _3/2) + φ _c], 0≤t≤T _C ,

where τ ₃ = 2R / C is the delay time of the re-emitted signal of the relative probing (figure 3);

R is the distance from the scanning unit to the transceiver located on the bombarded biological object or its remains;

ω _N is the frequency of the radiated probe signal;

ω _p is the frequency of the re-emitted signal;

γ = Δω _d / T _M is the rate of change of the signal frequency;

Δω _d - frequency deviation;

T _M - period of modulation.

The voltage of the local oscillator 14 is supplied to the second input of the mixer 15 (Fig. 4, c)

U _Г (t) = ν _g Cos (ω _g t + φ _g ).

At the output of the mixer 15, voltages of combination frequencies are generated. The amplifier 16 is allocated voltage intermediate (differential) frequency

U _pr (t) = ν _pr · Cos [ω _ave (t-τ ₃₎ + πγ (t-τ ₃₎ ² + φ _a (t-τ _3/2) + φ _etc.] 0≤t≤T _C ,

where ν _pr = 1/2 · ν ₄ · ν _g ;

ω _CR = ω _s - ω _g - intermediate (difference) frequency;

φ _CR = φ _s - φ _g ,

which is fed to the first input of the multiplier 17, to the second input of which a signal U ₁ (t) is supplied from the output of the frequency modulator 20. A voltage is generated at the output of the multiplier 17 (Fig. 4, b)

₅ U (t) = ν ₅ · Cos [ω _r t + φ _a (t-τ _3/2) φ _r],

where ν ₅ = 1/2 · ν _c · ν _pr ,

which is a PSK signal at the frequency of the local oscillator 14 and is fed to the first (information) input of the phase detector 6. At the second (reference) input of the phase detector 6, the voltage U _Г (t) of the local oscillator 14 is supplied as a reference voltage (Fig. 4, ) As a result of synchronous detection at the output of the phase detector 6, a low-frequency voltage is generated (figure 4, g)

_H U (t) = ν _n · Cos φ _to (t-τ _3/2) 0≤tT _C

where ν _n = 1/2 · ν ₅ · ν _g ,

proportional to the modulating code M (t) (Fig. 4, a). This voltage is recorded and analyzed in computer 7.

The received LFM-QPSK signal U ₄ (t) from the output of the high-frequency amplifier 5 is simultaneously fed to the first input of the multiplier 21, the second input of which is supplied with a low-frequency voltage U _H (t) from the output of the phase detector 6. An LFM signal is generated at the output of the multiplier

U ₆ (t) = ν ₆ · Cos [ω _s (t-τ ₃ ) + πγ (t-τ ₃ ) ² + φ _s ], 0≤t≤T _С ,

where ν ₆ = 1/2 · ν _n · ν ₆ ,

which is allocated by a band-pass filter 22 and fed to the first input of the multiplier 23, the second input of which is supplied with a chirp signal U ₁ (t) from the output of the frequency modulator 20. A low-frequency harmonic voltage is generated at the output of the multiplier

U ₇ (t) = ν ₇ Cos (ω _δ t + φ _δ ), 0≤t≤T _С ,

where ω _δ = 2πγτ ₃ is the beat frequency;

ν ₇ = 1 / 2ν _c · ν ₆ ,

which is allocated by a narrow-band filter 24 and is fed to the input of the frequency meter 25 (frequency analyzer). Frequency meter 25 is calibrated directly in range units.

The maximum range that can be measured by the frequency method is determined from the condition

T _M / 2≤2R / C,

where from

R _max = C · T _M / 4,

where C is the propagation velocity of the electromagnetic wave.

The minimum frequency of the beat spectrum, which can be detected by a spectrum analyzer (frequency meter 25), is equal to the modulation frequency

F _M = 1 / T _M.

Consequently, the minimum distance from the scanning unit to the transceiver unit located on the bombarded biological object or its remains, as measured by the frequency method, is determined by the expression

R _min = C / 4Δω _d .

The resolution of the frequency range finder is determined by the minimum difference in the frequencies of the beats, which can be recorded by the spectrum analyzer. It, as already noted, is equal to F _M. This difference corresponds to the allowed distance

ΔR = C / 4Δω _d .

A method and apparatus for detecting the location of bombarded biological objects or their remains provide an increase in the sensitivity and dynamic range of the receiver of the scanning unit, as well as an increase in the reading range of information about the biological object. This is achieved by constructing the receiver of the scanning unit according to the superheterodyne circuit. In addition, synchronous detection of the received QPSK signal is carried out at a stable frequency ω _g local oscillator, which does not require additional phase synchronization. In this case, the transceiver operates without a power source and provides a detection range of at least 2000 m.

Thus, the proposed method and device for detecting the location of buried bioobjects or their remains in comparison with prototypes and other technical solutions of a similar purpose provide an increase in the reliability of detecting the location of buried bioobjects or their remains. This is achieved by automatically determining the distance from the scanning unit to the transceiver unit located on the bombarded biological object or its remains, using the frequency method using linear frequency modulation.

From the point of view of detection, complex signals with combined linear frequency modulation and phase shift keying (LFM-PSK) have 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 LFM-QPSK signal at the receiving point may be masked by noise and interference. Moreover, the energy of a complex LFM-QPSK signal is by no means small; it is simply distributed over the time-frequency domain so that at each point in this region the signal power is less than the noise and interference power.

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

Claims (2)

1. A method for detecting the location of bombarded bioobjects or their remains, which consists in preliminary placing on a bioobject belonging to a risk group a low-power transceiver, which is used as a piezocrystal with an aluminum interdigital transducer deposited on its surface connected to a microstrip antenna and a set of reflectors , irradiation with the help of a scanning unit of a covered area, under the surface of which there may be a biological object or its remains directed by an electromagnet the final signal, receiving it on a bombarded biological object or its remains, converting it into an acoustic wave, ensuring its propagation over the surface of the piezocrystal and back reflection, converting the reflected acoustic wave again into an electromagnetic signal, the internal structure of which corresponds to the structure of the interdigital transducer, reradiating it to air , reception by the scanning unit, amplification in amplitude, frequency conversion using the local oscillator voltage, intermediate voltage isolation frequency, isolating the electromagnetic signal with phase shift keying at the local oscillator frequency, performing its synchronous detection using the local oscillator voltage as a reference voltage, registering the selected analog of the modulating code corresponding to the structure of the interdigital transducer, analyzing it and determining the ownership of the filled bioobject or its remains, characterized in that the directional electromagnetic signal before irradiation is modulated in frequency according to a sawtooth law, pre the reflected acoustic wave is formed into an electromagnetic complex signal with combined linear frequency modulation and phase shift keying, an amplified electromagnetic complex signal with combined linear frequency modulation and phase shift keying is frequency-converted using the local oscillator voltage, the intermediate frequency voltage is multiplied with the voltage of the master oscillator, modulated by frequency according to a sawtooth law, multiply amplified by electromagnetic electromagnetic complex with a signal with combined linear frequency modulation and phase shift keying with a dedicated analog of the modulating code, an electromagnetic signal with linear frequency modulation is isolated, it is multiplied with the voltage of the master oscillator, modulated in frequency according to a sawtooth law, the beat voltage is measured, the beat frequency is measured and the distance from the scanning unit is determined to the transceiver located on the bombarded biological object or its remains. 2. A device for detecting the location of buried bioobjects or their remains, containing a transceiver associated with the antenna and placed on a bioobject belonging to a risk group, a scanning unit consisting of a master oscillator and series-connected power amplifier, a circulator, the input-output of which is connected to the horn transceiver antenna, high-frequency amplifier, mixer, the second input of which is connected to the output of the local oscillator, the intermediate frequency amplifier, the first multiplier, the first bandpass an filter, a phase detector, the second input of which is connected to the output of the local oscillator, and a computer, the transceiver unit is made in the form of a piezocrystal with an aluminum thin-film interdigital transducer deposited on its surface connected to a microstrip antenna and a set of reflectors, the interdigital transducer contains two comb systems of electrodes, the electrodes of each of the combs are connected to each other by buses connected to a microstrip antenna, characterized in that it is equipped with a generator sawtooth voltage, frequency modulator, second and third multipliers, second band-pass filter, narrow-band filter and frequency meter, and a frequency modulator is connected to the output of the master oscillator, the second input of which is connected to the output of the sawtooth voltage generator, and the output is connected to the input of the power amplifier, to the output of the amplifier a high frequency, a second multiplier is connected in series, the second input of which is connected to the output of the phase detector, a second bandpass filter, a third multiplier, a second the input of which is connected to the output of the frequency modulator, a narrow-band filter and a frequency meter, the second input of the first multiplier is connected to the output of the frequency modulator.

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