RU2370792C2 - Method of location detection of burried bio-objects or their remains and device for its performance - Google Patents

Abstract

FIELD: mining.

SUBSTANCE: device comprises basic frequency generator 1, power amplifier 2, circulator 3, transceiving antenna 4, high frequency amplifier 5, phase detector 6, computer 7, heterodyne 8, first mixer 9, amplifier 10 of the first intermediate frequency, the second mixer 11, amplifier 12 of the second intermediate frequency, correlation device 19, multiplying device 20, filter 21 of low frequencies, optimising peak-holding controller 22, adjustable delay unit 23 and range indicator 24. Transceiving unit is made in the shape of piezocrystal 13 with interdigital transducer, applied on its surface and connected with microstrip antenna 14, and deflector set 18. Stress of heterodyne is kept for time τ, then it is multiplied by stress of the second intermediate frequency. Low frequency stress, proportional to the correlation function R (τ), is determined, then delay time τ is changed to equality access τ-τ₃, where τ₃=2R/c, R - distance to the burried bio-object or its remains. The specfied equality is maintained, that corresponds to maximum value of the correlation function R(τ). The distance R to the burried bio-object or its remains is determined. Pending stress of heterodyne is used for synchronous detection of the received signal with phase manipulation at the second intermediate frequency ω_int=ω_g.

EFFECT: enlargement of functional possibilities with determination of the distance to burried bio-objects or their remains.

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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 mountaineering when searching for bioobjects bombarded with, for example, avalanches or mountain landslides.

Known methods and devices for detecting the location of buried biological objects or their remains (RF patents No. 2085997, 2105432, 2116099, 2206902, 2248235, 2288486; US patents No. 4129868, 4673936; patent EP No. 0075199; V.K. Vinokurov and others. Mountain climbing safety - M .: 1983, p.136-137 and others).

Of the known methods and devices closest to the proposed are the "Method for detecting the location of buried biological objects or their remains and a device for its implementation" (RF patent No. 2288486, G01V 3/12, 2005), which are selected as the base objects.

The specified method and device provide an increase in sensitivity and an increase in the range of action.

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 isolated. Before radiation, the signal is converted in frequency using the local oscillator frequency and the voltage of the first intermediate frequency equal to the sum of the carrier frequency and the local oscillator frequency is isolated. The received signal with phase shift keying is re-converted in frequency. The voltage of the second intermediate frequency is isolated and synchronous detection is carried out at the frequency ω _{g of the} local oscillator.

The device comprises a scanning unit and a transceiver. The scanning unit contains a master oscillator, a circulator, a transceiver antenna, a phase detector, a computer, a local oscillator, the first and second mixers, amplifiers of the first and second intermediate frequencies and a piezocrystal, a microwave antenna, electrodes, a set of reflectors.

However, the known technical solutions do not provide the ability to determine the distance to the bombarded biological objects or their remains.

An object of the invention is to expand the functionality of the method and device by determining the distance to the bombarded biological objects or their remains.

The problem is solved in that a method for detecting the location of buried bioobjects or their remains, based on the closest analogue on what is previously placed on a bioobject belonging to a risk group, is a low-power transceiver, which is used as a piezocrystal with an aluminum counter-coated on its surface -shtyrevym converter connected to the microstrip antenna, and a set of reflectors, form a high-frequency oscillation with the carrier frequency ω _s, it is converted by ca Tote using frequency ω _r LO isolated voltage of the first intermediate frequency ω _pr1 equal to the sum frequency ω _pr1 = ω _r + ω _s, increase its power, is irradiated with a scanning unit bombarded portion below the surface which can be bioobject or its remains directed by an electromagnetic signal, they receive it on a bombarded biological object or its remains, convert it 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 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, receive by its scanning unit antenna, amplified by the amplitude, the received signal with phase shift keying at the first intermediate frequency ω _{CR1 is} repeatedly converted in frequency using the carrier frequency ω _s , the voltage of the second intermediate frequency ω _CR2 = ω _{CR1 -ω c} = ω _{g is isolated, reg} strip the selected modulating code corresponding to the structure of the interdigital transducer, analyze it and determine the affiliation of the buried biological object or its remains, differs from the closest analogue in that they delay the local oscillator voltage for a time τ, multiply it with the voltage of the second intermediate frequency, and emit a low-frequency voltage proportional of the correlation function R (τ), the delay time τ is changed until the equality τ = τ _{З occurs} , where τ _З = 2R / c, R is the distance to the filled bioobject or its remains s, maintain the indicated equality, which corresponds to the maximum value of the correlation function R (τ), determine the distance R to the bombarded biological object or its remains, and use the delayed local oscillator voltage to synchronously detect the received signal with phase shift keying at the second intermediate frequency ω _pr2 = ω _g .

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 piezoelectric crystal with an aluminum thin-film interdigital transducer deposited on its surface, associated with a microstrip antenna, and a set of reflectors, while the interdigital transducer contains two comb systems of electrodes, electrodes each one of the combs is 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, the amplifier of the first intermediate frequency, power amplifier, circulator, input-output which is connected to a horn transceiver antenna, high-frequency amplifier, second mixer, the second input of which is connected to the output of the master oscillator, amplifier of the second intermediate frequency, phase about the detector and the computer, differs from the closest analogue in that it is equipped with a multiplier, a low-pass filter, an extreme regulator, an adjustable delay unit and a range indicator, and an adjustable delay unit, a multiplier, the second input of which is connected to the second output, is connected in series to the second output of the local oscillator second intermediate frequency amplifier, low-pass filter, extreme regulator, adjustable delay unit and range indicator, the second input of the phase detector is connected to the first the output of the adjustable delay unit, the second input of the computer is connected to the second output of the adjustable delay unit.

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

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, a second mixer 11, the second input of which is connected to the output of the master oscillator 1, an amplifier 12 of the second intermediate frequency, a phase detector 6, the second input of which is connected to the W the local output of the local oscillator 8, and a computer 7, connected in series to the second output of the local oscillator 8, an adjustable delay unit 23, a multiplier 20, the second input of which is connected to the second output of the second intermediate frequency amplifier 12, a low-pass filter 21, an extreme regulator 22, and a range indicator 24 , a multiplier 20, a low-pass filter 21, an extreme controller 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 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 will connect the electrodes of each of the combs to each other. Tires 16 and 17 are in turn connected to the microstrip antenna 14.

The proposed method is implemented as follows.

The master oscillator 1 is formed of high-frequency oscillation (figure 4, a)

0≤t≤T_c,

0≤t≤T _c ,

where U _s , ω _s , φ _s , T _s is the amplitude, carrier frequency, initial phase and duration of the high-frequency oscillation, which is supplied to the first input of the first mixer 9, the second input of which supplies the voltage of the local oscillator 8 (Fig. 4, b)

The output of the mixer 9 is formed voltage of the Raman frequencies. The amplifier 10 is allocated the voltage of the first intermediate (total) frequency (figure 4, c)

0≤t≤T_c,

0≤t≤T _c ,

Where

K ₁ - gear ratio of the mixer;

ω _CR1 = ω _s + ω _G - the first intermediate (total) frequency;

φ _pr1 = φ _s + φ _G ,

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 latter 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. The tires, in turn, connected to the microwave 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;

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

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

The _received harmonic oscillation U _pr1 (t) 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 (FMN) (Fig. 4, e)

0≤t≤T_c,

0≤t≤T _c ,

where φ = _k {0, π} - manipulated component phase DPSK mapping law in accordance with a modulation code M (t) (4 g), _to which φ (t) = const at kτ _E <t <( k + 1) τ _Oe and can change abruptly at t = kτ _Oe , 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 = Nτ _E ).

In this case, the internal structure of the generated PSK signal is determined by the topology of the interdigital converter, 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 through the circulator 3 and the high-frequency amplifier 5 is supplied to the first input of the mixer 11, the second input of which is supplied with a high-frequency oscillation u _c (t) ( figure 4, a) from the output of the master oscillator 1 as the voltage of the second local oscillator. At the output of the mixer 11, voltages of combination frequencies are generated. The amplifier 12 is allocated the voltage of the second intermediate (differential) frequency (figure 4, e)

0≤t≤T_c,

0≤t≤T _c ,

Where

ω _pr2 = ω _{pr1 -ω c} = ω _g intermediate (difference) frequency;

φ _CR2 = φ _CR1 -φ _with = φ _G ;

τ ₃ = 2R / s is 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,

which is fed to the first input of the phase detector 6. The second input of the phase detector 6 is supplied with voltage u _g (t) from the second output of the local oscillator 8 through the adjustable delay unit 23. The output of the latter produces the following voltage

where τ is the delay time of the block 23 adjustable delay.

The voltage u _PR2 (t-τ) from the second output of the amplifier 12 of the second intermediate frequency is simultaneously supplied to the second input of the multiplier 20, the first input of which is supplied with the voltage u _g1 (t) from the output of 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 a correlation function R (τ) is formed.

The extreme controller 22 connected to the output of the low-pass filter 21 acts on the adjustable delay unit 23 and maintains the equality τ = τ _З , which corresponds to the maximum value of the correlation function R (τ).

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. In this case, the following voltage is supplied to the second input of the phase detector 6

which is used as a reference voltage for synchronously detecting a received signal with phase shift keying at a second intermediate frequency ω _pr2 u _pr2 (t-τ _З ).

The output of the phase detector 6 is formed of a low-frequency voltage (figure 4, g)

0≤t≤T_c,

0≤t≤T _c ,

Where

K ₂ - the transfer coefficient of the phase detector,

proportional to the modulating code M (t) (Fig. 4, d). This voltage, together with the measured range value R, is recorded and analyzed in computer 7.

The main characteristics of the device for detecting the location of biological objects or their remains include the following:

- transmitter power of the scanning unit - average not more than 100 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 _with T _c = 200 ... 1000, Δf _c - spectrum width);

- 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 events that could 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 life activity, but must bear necessary 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. The proposed method and device satisfy these requirements.

From the point of view of detection, 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, the broadband QPSK signal at the receiving point may be masked by noise and interference. Moreover, the energy of a broadband 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 power of noise and interference.

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

Broadband FMN 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.

Thus, the proposed method and device in comparison with prototypes and other technical solutions of a similar purpose provide a determination of the distance R to the bombarded biological objects or their remains. And 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 functionality of the known method and device is expanded.

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 belonging to a risk group, using a piezocrystal with an aluminum interdigital transducer deposited on its surface and connected to a microstrip antenna, and a set of reflectors, form a high-frequency oscillation with the carrier frequency ω _s, it is converted in frequency by using frequency ω _r LO isolated voltage of the first intermediate frequency ω _pr1 equal ω _pr1 = ω _r + ω _with the sum frequency, increase its power, is irradiated with a scanning unit the filled portion under the surface which can be bioobject or its remains, directional electromagnetic signal, taking it to strewn biooekte or its remains are converted into an acoustic wave, ensure its propagation over the surface of the piezocrystal and back reflection, convert the reflected acoustic wave again into an electromagnetic signal with phase shift keying, int nnyaya whose structure corresponds interdigital transducer formed by a signal with phase shift keying reemit microstrip antenna in ether, take its antenna scanning unit increase in amplitude, the received signal is phase shift keyed in the first intermediate frequency ω _pr1 re-converted in frequency with the carrier frequency ω _s , isolate the voltage of the second intermediate frequency ω _pr2 = ω _{pr1 -ω c} = ω _g , register the selected modulating code corresponding to the structure of the pin transducer, analyze it and determine the affiliation of the buried biological object or its remains, characterized in that they delay the local oscillator voltage for a time τ, multiply it with a voltage of the second intermediate frequency, isolate a low-frequency voltage proportional to the correlation function R (τ), change the delay time τ to the occurrence of the equality τ = τ _З , where τ _З = 2R / s, R is the distance to the bombarded bioobject or its remains, this equality is maintained, which corresponds to the maximum correlation value -th function R (τ), determine the distance R to the bombarded biological object or its remains and use the delayed local oscillator voltage to synchronously detect the received signal with phase shift keying at the second intermediate frequency ω _pr2 = ω _g . 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 output of the master oscillator, an amplifier of the second intermediate frequency, a phase detector and a computer, characterized in that it is equipped with a multiply a low-pass filter, an extremal regulator, an adjustable delay unit and a range indicator, and an adjustable delay unit, a multiplier, the second input of which is connected to the second output of the amplifier of the second intermediate frequency, a low-pass filter, an extreme controller, an adjustable unit, are connected in series to the second output of the local oscillator delay and range indicator, the second input of the phase detector is connected to the first output of the adjustable delay unit, the second input of the computer is connected to the second output Lok adjustable delay.

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