RU2410729C1 - Method of detecting location of filled bio-objects or remains thereof and device for realising said method - Google Patents

Abstract

FIELD: physics; geophysics.

SUBSTANCE: invention relates to search and rescue operations. The device which realises the disclosed method has a scanning unit and a transceiver. The scanning unit has a master generator 1, a power amplifier 2, a circulator 3, a transceiving horn antenna 4, a high frequency amplifier 5, a phase detector 6, a computer 7, a heterodyne 8, a first mixer 9, a first intermediate frequency amplifier 10, a second amplifier 11, a second intermediate frequency first amplifier 12, a correlator 19, a first multiplier 20, a low-pass filter 21, an amplifier 22, a controlled delay unit 23, a range indicator 24, a first 25 and a second 28 90°-degree phase changer, a third amplifier 26, a second intermediate frequency second amplifier 27, an adder 29, an amplitude detector 32, a switch 33 and a differentiator 34. The transceiver has a piezocrystal 13, a microstrip antenna 14, electrodes 15, buses 16 and 17, a set of reflectors 18.

EFFECT: high noise immunity and accuracy of determining distance to filled bio-objects or their remains by suppressing spurious signals (noise), received over a mirror and a composite channel, and using a derived correlation function.

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Description

The invention relates to the field of search and rescue operations and can be used to search for living people or their remains in areas of earthquakes and explosions of residential buildings as a result of leakage of domestic gas, in rubble and shelters, as well as in mountaineering when searching for people covered with, for example, snow avalanches and rockfalls.

Known methods and devices for detecting the location of buried bioobjects or their remains (RF patents Nos. 2076336, 2085997, 2105432, 2116099, 2141119, 2206902, 2245733, 2248235, 2288486, 2313108, 2370792; US patents Nos. 4129868, 4673936, 491 588, 4673936, 4958638, 4958638, 4958638, 4958638 EP patent No. 0075119; Vinokurov VK and others. Safety in mountaineering. - M .: 1983, p. 136-137 and others).

Of the known methods and devices closest to the proposed one is the "Method for detecting the location of buried bioobjects or their remains and a device for its implementation" (RF patent No. 2370792, G01V 3/12, 2007), which are selected as the base objects.

The specified method and device provide a determination of the distance to the bombarded bioobjects or their remains.

For this, a low-power transceiver, which is used as a transducer based on surface acoustic waves (SAWs), is preliminarily placed on a bioobject belonging to a risk group. An area is irradiated, under the surface of which a biological object or its remains can be located, directed by an electromagnetic signal. A re-emitted signal is received, a modulating code is selected that displays the identification number of the biological object or its remains. Before radiation, the probe signal is converted in frequency using the local oscillator frequency and the voltage of the first intermediate frequency w _pr1 is equal to the sum of the carrier frequency w _s and the frequency w _{g of the} local oscillator:

w _pr1 = w _g + w _s .

The re-emitted signal with phase shift keying is repeatedly converted in frequency, the voltage of the second intermediate frequency is isolated:

w _pr2 = w _pr1 -w _c = w _g .

and carry out synchronous detection at a frequency w _g local oscillator.

The device that implements the method, the same value of the second intermediate frequency w _np2 may be obtained by receiving signals at two frequencies w and w _{pr1 s,} i.e.

w _pr2 = w _pr1 -w _s and w _pr2 = w _s -w _s .

Therefore, if the frequency channel w _pr1 adopts the configuration reception, then along with it will take place mirror reception channel frequency w which is _of a different frequency w _pr1 on 2w _np2 and located symmetrically (mirror) relative to the carrier frequency w _c (FIG. 2). Conversion on the mirror channel of reception occurs with the same conversion coefficient K _pr as on the main channel, therefore it most significantly affects the selectivity, noise immunity and accuracy of determining the distance to the bombarded biological objects or their remains.

In addition to the mirror, there are other additional (combinational) reception channels. In general terms, any Raman receive channel takes place under the conditions

w _pr2 = [± mw _ki ± nw _s ],

where w _кi is the frequency of the i-th Raman reception channel;

m, n, i are positive integers, including n = 0.

The most harmful combinational reception channels are those generated by the interaction of the first harmonic of the second intermediate frequency with the harmonics of the carrier frequency w _{from a} small order (second, third, etc.), since the sensitivity of the device through these channels is close to the sensitivity of the main channel. So, two combination channels with m = 1 and n = 2 correspond to frequencies:

W _k1 = 2w _s -w _pr2 and w _k2 = 2w _s + w _pr2 .

The presence of false signals (interference) received via additional channels leads to a decrease in noise immunity and accuracy in determining the distance to bombarded bioobjects or their remains.

In addition, to accurately determine the distance to the bombarded biological objects or their remains, it is necessary to more accurately determine the value of the adjustable delay τ _s corresponding to the maximum of the correlation function R (τ) (Fig. 4).

. В точке τ=τ_з производная имеет значительную крутизну и, кроме того, меняет знак в зависимости от положения относительно точки τ=0.However, in the region of the maximum, the correlation function R (τ) has a very small slope and changes insignificantly with changes in τ. Much more favorable for finding the maximum is the form of the derivative of the correlation function

. At the point τ = τ _{s, the} derivative has a significant steepness and, in addition, changes sign depending on the position relative to the point τ = 0.

An object of the invention is to increase the noise immunity and accuracy of determining the distance to the bombarded biological objects or their remains by suppressing false signals (interference) received through the mirror and Raman channels, and using the derivative of the correlation function.

, изменяют время задержки τ до момента прохождения производной корреляционной функции

через нуль, определяют время задержки τ_з=2R/C, где R - расстояние до засыпанного биообъекта или его останков, C - скорость распространения радиоволн, поддерживают производную корреляционной функции на нулевом уровне.The problem is solved in that a method for detecting the location of buried bioobjects or their remains, based, in accordance with the closest analogue, on that a low-power transceiver is used, which is used as a piezocrystal with aluminum deposited on its surface, on a bioobject belonging to a risk group an interdigital transducer associated with a microstrip antenna and a set of reflectors form a high-frequency oscillation with a carrier frequency w _s , transform it by the hour using the frequency w _{g of the} local oscillator, isolate the voltage of the first intermediate frequency w _pr1 , equal to the sum of the frequencies w _pr1 = w _g + w _s , amplify it in power, irradiate with the help of a scanning unit a covered area, under the surface of which there may be a biological object or its remains directed by an electromagnetic signal, it is received on a bombarded bioobject or on its remains, converted into an acoustic wave, ensure its propagation over the surface of the piezocrystal and back reflection, transform the reflected acoustic the wave again into an electromagnetic signal with phase shift keying, the internal structure of which corresponds to the structure of the interdigital transducer, the generated signal with phase shift keying is re-emitted by the microstrip antenna into the ether, it is received by the antenna of the scanning unit, amplified in amplitude, the received signal with phase shift keying at the first intermediate frequency w _CR1 re-convert in frequency using harmonic oscillations of the carrier frequency w _s , emit the first voltage of the second intermediate h The frequency w _pr2 = w _pr1 -w _c = w _g , register the selected modulating code corresponding to the structure of the interdigital transducer, analyze it and determine the affiliation of the filled bioobject or its remains and delay the local oscillator voltage for a time τ, differs from the closest analogue in that the received signal with phase shift keying at the first intermediate frequency w _{pr1 is reconverted} in frequency using harmonic oscillations of the carrier frequency w _s phase-shifted by 90 °, a second voltage of the second daily frequency w _CR2 = w _CR1 -w _c = w _g , phase shifted by 90 °, summed with the first voltage of the second intermediate frequency, multiply the total voltage of the second intermediate frequency w _CR2 with the received signal with phase shift at the first intermediate frequency w _CR1 , emit harmonic oscillation at the carrier frequency w _s , detect it by amplitude and use the detected voltage as a control voltage to open the key, through which the total voltage of the second intermediate frequency w _{pr2 is passed} , It is synchronously detected using the delayed local oscillator voltage as a reference voltage, while the total voltage of the second intermediate frequency is differentiated by time, multiplied by the local oscillator voltage delayed by time τ, a low-frequency voltage proportional to the derivative of the correlation function is isolated

change the delay time τ until the derivative of the correlation function passes

through zero, determine the delay time τ _s = 2R / C, where R is the distance to the bombarded biological object or its remains, C is the propagation velocity of radio waves, they support the derivative of the correlation function at zero level.

The problem is solved in that a device for detecting the location of buried bioobjects or their remains, containing, in accordance with the closest analogue, a transceiver located on a bioobject belonging to a risk group and made in the form of a piezocrystal with an aluminum thin-film interdigital applied to its surface a transducer associated with a microstrip antenna and a set of reflectors, while the interdigital transducer contains two comb systems of electrodes, electrodes of each the dies of the combs are connected to each other by buses connected to the microstrip antenna, and a scanning unit consisting of a serially connected master oscillator, a first mixer, the second input of which is connected to the first output of the local oscillator, the amplifier of the first intermediate frequency, the power amplifier, the circulator, input-output which is connected to a horn transceiver antenna, a high-frequency amplifier, a second mixer, the second input of which is connected to the first output of the master oscillator, and the first amplifier, the second intermediate frequency, sequentially connected phase detector, the second input of which is connected to the first output of the adjustable delay unit, and a computer, the second input of which is connected to the second output of the adjustable delay unit, connected in series to the second output of the local oscillator of the adjustable delay unit, the first multiplier and low-pass filter, at the same time, a range indicator is connected to the second output of the adjustable delay unit, differs from the closest analogue in that it is equipped with two 90 ° phase shifters, a third mixture an amplifier, a second amplifier of a second intermediate frequency, an adder, a second multiplier, a narrow-band filter, an amplitude detector, an amplifier, a key, and a differentiator, and the first 90 ° phase shifter, the third mixer, the second input of which is connected to the output of the high amplifier, are serially connected to the second output of the master oscillator frequency, the second amplifier of the second intermediate frequency, the second phase shifter 90 °, an adder, the second input of which is connected to the output of the first amplifier of the second intermediate frequency, second swarm multiplier, the second input of which is connected to the output of the high-frequency amplifier, a narrow-band filter, an amplitude detector and a key, the second input of which is connected to the output of the adder, and the output is connected to the first input of the phase detector and through the differentiator to the second input of the first multiplier, the second input of the adjustable unit delays through an amplifier connected to the output of a low-pass filter.

показан на фиг.4. Временные диаграммы, поясняющие работу устройства, представлены на фиг.5.A block diagram of a device that implements the proposed method is presented in figures 1 and 3. A frequency diagram illustrating the process of converting signals by frequency is shown in figure 2. The form of the correlation function R (τ) and its derivative

shown in figure 4. Timing diagrams explaining the operation of the device are presented in figure 5.

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

The scanning unit contains a serially connected master oscillator 1, a first mixer 9, the second input of which is connected to the first output of the local oscillator 8, an amplifier 10 of the first intermediate frequency, a power amplifier 2, a circulator 3, the input-output of which is connected to a horn transceiver antenna 4, an amplifier 5 high frequency, the second mixer 11, the second input of which is connected to the first output of the master oscillator 1, and the first amplifier 12 of the second intermediate frequency, connected in series to the second output of the master oscillator 1 first the first phase shifter 25 by 90 °, the third mixer 26, the second input of which is connected to the output of the high-frequency amplifier 5, the second amplifier 27 of the second intermediate frequency, the second phase shifter 28 by 90 °, the adder 29, the second input of which is connected to the output of the first amplifier 12 of the second intermediate frequency, a second multiplier 30, the second input of which is connected to the output of the high-frequency amplifier 5, a narrow-band filter 31, an amplitude detector 32, a key 33, the second input of which is connected to the output of the adder 29, a phase detector 6, the second input of which is connected to the first output of the adjustable delay unit 23, and a computer 7, the second input of which is connected to the second output of the adjustable delay unit 23, connected in series to the second output of the local oscillator 8, the adjustable delay unit 23, the first multiplier 20, the second input of which is connected through the differentiator 34 to the output of the key 33 , a low-pass filter 21 and an amplifier 22, the output of which is connected to the second input of the adjustable delay unit 23, to the second output of which a range indicator 24 is connected.

The second multiplier 20, a low-pass filter 21, an amplifier 22 and an adjustable delay unit 23 form a correlator 19.

The transceiver unit is made in the form of a piezocrystal 13 with an aluminum thin-film interdigital transducer (IDT) deposited on its surface connected to a microstrip antenna 14 and a set of reflectors 18.

The interdigital transducer of surface acoustic waves (SAW) contains two comb systems of electrodes 15, buses 16 and 17, which connect the electrodes of each of the combs to each other. Tires 16 and 17, in turn, are connected to the microstrip antenna 14.

The proposed method is implemented as follows.

The master oscillator 1 is formed of high-frequency oscillation (Fig.5, a)

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

where U _c , w _c , φ _c , T _c - amplitude, carrier frequency, initial phase and duration of high-frequency oscillations;

which is fed to the first input of the first mixer 9, the second input of which is the voltage of the local oscillator 8 (Fig.5, b)

u _g (t) = U _g Cos (w _g t + φ _g ).

At the output of the mixer, combinational frequency voltages are generated. The amplifier 10 is allocated the voltage of the first intermediate (total) frequency (figure 5, c)

u _CR1 (t) = U _CR1 · Cos (w _CR1 t + φ _CR1 ), 0≤t≤T _s ,

where U _pr1 = ЅU _with · U _g ;

w _pr1 = w _g + w _s - the first intermediate (total) frequency;

φ _CR1 = φ _g + φ _s ,

which, after amplification in the power amplifier 2, 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.

The electromagnetic signal u _pr1 (t) is received by the microstrip antenna 14 of the transceiver located on the biological object or its remains. The transceiver is a piezocrystal 13 with an aluminum thin-film interdigital SAW transducer deposited on its surface, which consists of two comb systems of electrodes 15 deposited on the surface of the piezocrystal 13. The electrodes of each of the combs are connected to each other by buses 16 and 17. Tires turn associated with microstrip antenna 14.

The principle of operation of the interdigital transducer of a surfactant is based on the fact that the electric fields in space and time created in a piezoelectric crystal by a system of electrodes cause elastic strains due to the piezoelectric effect, which propagate in the crystal as a surfactant.

Surface acoustic waves are waves propagating along the surface of solids in a relatively thin surface layer. The propagation velocity of surfactants in crystals is approximately five orders of magnitude lower than the propagation velocity of electromagnetic waves. This means that on the centimeter of the crystal, you can place information that will fill a kilometer-long cable.

The high information capacity of instruments based on surface acoustic waves was first used in delay lines, which make it possible to store, transform, channel, divert and reflect the signals propagating in them.

The basis of the operation of devices on surfactants are three physical processes:

- conversion of the input electrical signal into an acoustic wave;

- propagation of an acoustic wave along the surface of the sound duct;

- reflection and inverse transformation of the surfactant into an electrical signal.

For direct and inverse transformations of surfactants, transducers of surface acoustic waves are used. The most common among them are interdigital converters.

The _received harmonic oscillation u _pr1 (t) (Fig. 5, c) is converted by an interdigital transducer into an acoustic wave that propagates along the surface of the piezoelectric crystal 13, is reflected from a set of 18 reflectors, and is again converted into an electromagnetic signal with phase shift keying (QPS) (Fig. .5, d)

u ₂ (t) = U ₂ · Cos [w _{pr1 to} t + φ (t) + φ _pr1] 0≤t≤T _s,

where φ _к (t) = {0, π} is the manipulated component of the phase, which displays the law of phase manipulation in accordance with the modulating code M (t) (Fig. 5, e), and φ _к (t) = const at Кτ _э < t <(k + 1) τ _e and can change abruptly at t = Kτ _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 a signal of duration T _s (T _s = N · τ _e ).

In this case, the internal structure of the generated PSK signal is determined by the topology of the interdigital transducer, has an individual character and contains all the necessary unique information about the owner, for example, last name, first name, middle name, year of birth, etc.

The generated QPSK signal u ₂ (t) is radiated by the microstrip antenna 14, received by the antenna of the scanning unit 4, and fed through the circulator 3 and the high-frequency amplifier 5 to the first inputs of the mixers 11 and 26, the second inputs of which are supplied with the voltage of the master oscillator 1:

U _c (t) = U _c Cos (w _c t + φ _s ),

u _c ¹ (t) = U _c Cos (w _c t + φ _s + 90 °), 0≤t≤T _s .

At the input of the mixers 11 and 26, voltages of combination frequencies are generated. Amplifiers 12 and 27 are allocated voltage of the second intermediate (differential) frequency:

u _pr2 (t-τ _e ) = U _pr2 · Cos [w _pr2 (t-τ _z ) + φ _k (t-τ _z ) + φ _pr2 ],

u _pr3 (t-τ _e ) = U _pr2 · Cos [w _pr2 (t-τ _z ) + φ _k (t-τ _z ) + φ _pr2 -90 °],

where U _pr2 = ЅU ₂ · U _c ;

w _CR2 = w _CR1 -w _c = w _g - the second intermediate (difference) frequency;

φ _CR2 = φ _CR1 -φ _with = φ _g ;

- время запаздывания переизлученного сигнала;

- the delay time of the re-emitted signal;

R is the distance to the bombarded bioobject or its remains;

C is the propagation velocity of radio waves.

The voltage u _CR3 (t-τ _s ) from the output of the amplifier 27 of the second intermediate frequency is supplied to the input of the phase shifter 28 by 90 °, at the output of which the following voltage is generated:

u _pr4 (t-τ _z ) = U _pr2 · Cos [w _pr2 (t-τ _z ) + φ _k (t-τ _z ) + φ _pr2 -90 ° + 90 °] =

U _pr2 · Cos [w _pr2 (t-τ _z ) + φ _k (t-τ _z ) + φ _pr2 ].

The voltage u _CR2 (t-τ _e ) and u _CR4 (t-τ _e ) are supplied to the two inputs of the adder 29, the output of which is formed by the total voltage (Fig.5, e)

u _Σ (t-τ _z ) = U _Σ · Cos [w _pr2 (t-τ _z ) + φ _k (t-τ _z ) + φ _pr2 ], 0≤t≤T _s ,

where U _Σ = 2U _pr2 ,

which is fed to the second input of the multiplier 30, the first input of which receives the received QPSK signal

u ₂ (t-τ _s ) = U ₂ · Cos [w _pr1 (t-τ _s ) + φ _to (t-τ _s ) + φ _pr1 ],

from the output of the high frequency amplifier 5.

The output of the multiplier 30 produces a harmonic voltage

U ₃ (t) = U ₃ · Cos (w _c t + φ _s ), 0≤t≤T _s ,

where U ₃ = ЅU ₂ · U _Σ ,

which is allocated by the narrow-band filter 31, is detected by the amplitude detector 32 and is fed to the control input of the key 33, opening it. The key 33 in the initial state is always closed. The tuning frequency w _{n of the} narrow _- band filter 31 is selected equal to the carrier frequency w _{c of the} master oscillator 1 (w _n = w _c ).

In this case, the total voltage u _Σ (t-τ _s ) (Fig. 5, e) from the output of the adder 29 through the public key 33 is supplied to the input of the differentiator 34 and to the first (information) input of the phase detector 6, to the second (reference) input of which the voltage of the local oscillator 8 through the block 23 adjustable delay

u _g (t-τ _s ) = U _g Cos (w _g (t-τ _s ) + φ _g )

This voltage is used as a reference voltage. As a result of synchronous detection at the output of the phase detector 6, a low-frequency voltage is generated (figure 5, g)

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

Where

proportional to the modulating code M (t) (Fig. 5, d). This voltage is recorded and analyzed in computer 7.

(фиг.4). Блоком 23 регулируемой задержки изменяют время задержки τ до момента прохождения производной корреляционной функции

через нуль. Индикатор 24 дальности, связанный с блоком 23 регулируемой задержки, позволяет непосредственно считывать измеренное значение дальности R до засыпанного биообъекта или его останков. Измеренное значение дальности R регистрируется и анализируется в компьютере 7.The voltage u _Σ (t-τ _s ) from the output of the adder 29 through the public key 33 and the differentiator 34 is supplied to the second input of the multiplier 20, the first input of which is supplied to the voltage u _g (t) of the local oscillator 8 through the adjustable delay unit 23. The voltage obtained at the output of the multiplier 20 is passed through a low-pass filter 21, at the output of which an arbitrary correlation function is formed

(figure 4). The adjustable delay unit 23 changes the delay time τ until the derivative of the correlation function passes

through zero. The range indicator 24, associated with the adjustable delay unit 23, allows you to directly read the measured value of the range R to the bombarded bioobject or its remains. The measured value of the range R is recorded and analyzed in the computer 7.

The operation of the scanning unit described above corresponds to the case of receiving useful PSK signals along the main channel at a frequency w _pr1 (Fig. 2).

If a false signal (interference) is received on the mirror channel at a frequency w _s

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

the amplifiers 12 and 27 of the second intermediate frequency are allocated the following voltage

u _pr5 (t) = U _pr5 Cos (w _pr2 t + φ _pr5 ),

u _CR6 (t) = U _CR5 · Cos (w _CR2 t + φ _CR5 + 90 °), 0≤t≤T _s ,

where U _pr5 = ЅU ₃ · U _s ;

_np2 w = w _r + w _h - first intermediate (cumulative) frequency;

φ _pr5 = φ _s + φ _s .

The voltage u _pr6 (t) from the output of the amplifier 27 of the second intermediate frequency is supplied to the input of the phase shifter 28 by 90 °, at the output of which a voltage is generated

u _pr7 (t) = U _pr5 · Cos (w _pr2 t + φ _pr5 + 90 ° + 90 °) = - U _pr5 · Cos (w _pr2 t + φ _pr2 ), 0≤t≤T _s .

The _voltages u _CR5 (t) and u _CR7 (t) _applied to the two outputs of the adder 29 are compensated at its output.

Therefore, a false signal (interference) received on the mirror channel at a frequency w _s is suppressed by the phase compensation moment.

For a similar reason, a false signal (interference) received on the first combination channel at a frequency w _{k1 is also} suppressed.

If a false signal (interference) receives on the second combination channel at a frequency w _k2

u _k2 (t) = U _k2 · Cos (w _k2 t + φ _k5 ), 0≤t≤T _k2 ,

the amplifiers 12 and 27 of the second intermediate frequency are allocated the following voltages:

u _pr8 (t) = U _pr8 · Cos (w _pr2 t + φ _pr8 ),

u _pr9 (t) = U _pr9 · Cos (w _pr2 t + φ _pr8 -90 °), 0≤t≤T _k2 ,

where U = _{pr8 ^half} U _k2 · U _s;

w _pr2 = w _k2 + w _s - the first intermediate (total) frequency;

φ _pr8 = φ _k2 + φ _s .

The voltage u _pr9 (t) from the output of the amplifier 27 of the second intermediate frequency is supplied to the input of the phase shifter 28 by 90 °, at the output of which a voltage is generated

U _pr8 (t) = U _pr8 · Cos (w _pr2 t + φ _pr8 -90 ° + 90 °) = U _pr8 · Cos (w _pr2 t + φ _pr 8), 0≤t≤T _k2

The voltage u _pr8 (t) and u _pr10 (t) are supplied to the two inputs of the adder 29, at the input of which the total voltage is formed

u _Σ1 (t) = U _Σ1 · Cos (w _CR2 t + φ _CR8 ), 0≤t≤T _k2 ,

where U _Σ1 = 2U _pr8 ,

which is fed to the second input of the multiplier 30, the first input of which receives the received false signal (interference) u _k2 (t) from the output of the high-frequency amplifier 5.

The output of the multiplier 30 produces a harmonic voltage

u ₄ (t) = U ₄ · Cos (2w _c t + φ _s ), 0≤t≤T _k2 ,

wherein U ₄ = _^1/2 U _k2 · U _Σ1,

which does not fall into the passband of the narrow-band filter 31. The key 33 does not open and the false signal (interference) received on the second combined channel at a frequency w _k2 is suppressed by the narrow-band filtering method.

The main characteristics of the device for detecting the location of a biological object or its remains may include the following:

- transmitter power of the scanning unit - average no more than 10 mW;

- frequency range - 900 ... 920 MHz;

- detection range - not less than 2000 m;

- the number of code combinations - 2 ³² ... 2 ¹²⁸ ;

- type of emitted signal - harmonic oscillation;

- type of reflected (re-emitted) signal — broadband signal with phase shift keying (signal base B = Δf _s · T _c = 200 ... 1000, where Δf _c is the width of the spectrum);

- dimensions of the transceiver located on the biological object or its remains 8 × 15 × 5 mm;

- the service life of the transceiver is not less than 20 years;

- power consumed by the transceiver - 0 W.

Each prospective participant in activities that may make this participant potentially affected is a risk group and should be equipped with a fairly simple, reliable and miniature device (such as a keychain, ring or small medallion) that should not impede the owner’s normal activities, but should bear You need unique information about this owner.

The second important requirement for this device is the ability to remotely read the information that it carries, an unlimited number of times, without any involvement of the owner and after a long time, for example, after an earthquake. These requirements are met by a SAW transceiver.

From the point of view, complex QPSK signals have energetic and structural secrecy.

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

The structural secrecy of complex QPSK signals is 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 complex QPSK signals of an a priori unknown structure in order to increase the sensitivity of the receiving device.

Complex QPSK signals allow the use of a new type of selection - structural selection. This means that there is a new opportunity to distinguish these signals from other signals and interference operating in the same frequency band and at the same time intervals.

Using the directional properties of the horn antenna of the scanning unit and the measured distance R, it is possible to determine the location of the bombarded biological objects or their remains.

Thus, the proposed method and device in comparison with basic objects and other technical solutions of a similar purpose provide increased noise immunity and accuracy of determining the distance to the bombarded biological objects or their remains. This is achieved by suppressing false signals (interference) received through the mirror and Raman channels, and using the derivative of the correlation function. At the point τ = 0, the derivative has a significant steepness and, in addition, changes sign depending on the position relative to the point τ = 0.

The method of measuring the distance to the bombarded biological objects or their remains to the minimum derivative of the correlation function (passing through zero), along with high accuracy and sensitivity, has another very significant advantage of the zero method, namely, the amplitude of the input signals and its fluctuations do not affect the measurement result .

Claims (2)

1. A method for detecting the location of buried bioobjects or their remains, based on the fact that a low-power transceiver is used as a pre-transmitter on a bioobject, 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, form a high-frequency oscillation with a carrier frequency W _c , convert it in frequency using the frequency w _{g of the} local oscillator, isolate the voltage first th intermediate frequency w _pr1 , equal to the sum of frequencies w _pr1 = w _g + w _s , amplify it by power, irradiate with the help of a scanning unit a filled area, under whose surface there may be a biological object or its remains directed by an electromagnetic signal, receive it on a filled biological object or its remains, they are converted into an acoustic wave, ensure its propagation over the surface of the piezocrystal and back reflection, they transform the reflected acoustic wave again into an electromagnetic signal with phase shift keying, inside NJ whose structure corresponds interdigital transducer formed by a signal with phase shift keying reradiated microstrip antenna in ether, take its antenna scanning unit increase in amplitude, the received signal is phase shift keyed in the first intermediate frequency w _pr1 re-converted in frequency with the harmonic oscillations carrier frequency w _s, emit a first voltage of the second intermediate frequency w = w _{pr1 np2 with} -w = w _g, registering the selected modulating code soot etstvuyuschy structure interdigital transducer, analyze it and determine the status of the filled biological object or its remains and delay oscillator voltage at time τ, characterized in that the receiving signal is phase shift keyed in the first intermediate frequency w _pr1 re-converted in frequency with the harmonic oscillations carrier frequency w _s phase-shifted by 90 °, the second voltage of the second intermediate frequency is _allocated w _pr2 = w _pr1 -w _c = w _g , phase-shifted by 90 °, summed with the first voltage the second intermediate frequency, multiply the total voltage of the second intermediate frequency w _CR2 with the received signal with phase manipulation at the first intermediate frequency w _CR1 , emit harmonic oscillation at the carrier frequency w _c , detect it by amplitude and use the detected voltage as the control voltage to open the key, through which a total voltage of the second intermediate frequency w _np2, it is carried out synchronous detection using the delayed voltage hetero ina as the reference voltage while the total voltage of the second intermediate frequency is differentiated with respect to time, it is multiplied with the local oscillator voltage delayed by time τ, emit a low-frequency voltage proportional to the derivative of the correlation function

change the delay time τ until the derivative of the correlation function passes

through zero, determine the delay time τ ₃ = 2R / C, where R is the distance to the bombarded biological object or its remains, C is the propagation velocity of radio waves, the derivative of the correlation function is maintained at a zero level. 2. A device for detecting the location of bombarded bioobjects or their remains, containing a transceiver located on a bioobject belonging to a risk group and 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, wherein 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, and a scanning unit, consisting of a serially connected master oscillator, a first mixer, the second input of which is connected to the first output of the local oscillator, an amplifier of the first intermediate frequency, power amplifier, circulator, the input-output of which is connected to a horn transceiver antenna, high-frequency amplifier, the second mixer, the second input of which is connected to the first output of the master oscillator, and the first amplifier of the second intermediate frequency, a phase detector connected in series, the second input to It is connected to the first output of the adjustable delay unit, and a computer, the second input of which is connected to the second output of the adjustable delay unit, connected in series to the second output of the local oscillator of the adjustable delay unit, the first multiplier and a low-pass filter, while an indicator is connected to the second output of the adjustable delay unit range, characterized in that it is equipped with two phase shifters 90 °, the third mixers, the second amplifier of the second intermediate frequency, the adder, the second multiplier, narrow a filter, an amplitude detector, an amplifier, a key and a differentiator, and the first phase shifter 90 °, the third mixer, the second input of which is connected to the output of the high-frequency amplifier, the second amplifier of the second intermediate frequency, the second phase shifter 90 ° are connected to the second output of the master oscillator , an adder, the second input of which is connected to the output of the first amplifier of the second intermediate frequency, the second multiplier, the second input of which is connected to the output of the high-frequency amplifier, narrowband filter, amplitude detector and key, the second input of which is connected to the output of the adder, and the output is connected to the first input of the phase detector and through the differentiator to the second input of the first multiplier, the second input of the adjustable delay unit is connected through the amplifier to the output of the low-pass filter.

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