RU2260816C2 - Method for detection of living objects and device for its realization - Google Patents

Abstract

FIELD: radio detection and finding, applicable for detection of alive people in slide rocks, shelters, under snow, as well as for remote contactless determination of the respiration rate and sylesoles in medical offices.

SUBSTANCE: the device realizing the offered method has a radio-frequency oscillator, directional coupler, pulse modulator, antenna unit, quadrature demodulator, two preamplifiers, two band-pass-filters, two multiplexers, two demodulators, two short-circuiting electronic switches, two low-frequency amplifiers, analog-to-digital converter multiplexer control unit, demultiplexer control unit, digital processing unit display unit, polarizer, transmitting antenna, two receiving antennas, two RF amplifiers, three keys, multiplier, narrow-band filter, frequency shifter, mixer, intermediate-frequency amplifier, amplitude limiter, phase detector and a comparison unit.

EFFECT: expanded functional potentialities and improved operating characteristics.

2 cl, 2 dwg

Description

The proposed method and device relate to radar and can be used to detect living people and their remains in the rubble, shelters, under the snow, as well as for remote non-contact determination of respiratory rate and heart rate in medical institutions.

Known methods and devices for the remote detection of people behind radiolucent barriers, as well as remote measurement of respiratory rate and heart rate using a monochromatic radio frequency sounding signal [1]. However, they do not select signals in range, which does not allow excluding interference from objects located at other than the desired ranges, for example, the influence of the operator, the influence of remote moving objects, etc. In the method and device described in [2], a linear frequency modulation of the probe signal is used, which allows for spatial resolution and increased noise immunity. However, this method does not allow to eliminate the signals caused by reflections of the probe radiation from stationary objects. These signals can be many times superior to those caused by breathing and heartbeat, and make detection difficult. A known method of processing broadband signals [3], based on gating the signal at successive times, storing the signal values on an electric capacitance, analog-to-digital conversion and subsequent parallel digital processing using relatively low-frequency digital devices. However, this method does not provide the proper dynamic range when processing signals in real time.

A known method and device [4], in which to implement spatial resolution, pulse modulation of the probe signal is used, and to reduce the level of signals caused by reflections from stationary objects, beat signals are generated with respect to several reference signals that differ in phase, and the beat signal with the smallest constant component. However, complete compensation of the constant component caused by reflections from stationary objects does not occur; sensitivity to small movements of the object as a function of distance has an oscillating character. In addition, the method requires a separate measurement cycle for each given range, which reduces its speed.

There is also a method of searching for people who have been bombarded with the help of specially trained dogs [5], which is subjective in nature and has a dependence on the quality of the dogs, their training, weather and climatic conditions, which impairs the accuracy and operational capabilities of the method.

Closest to the proposed method and device are the "Method for detecting living objects and a device for its implementation" [6], which are selected as prototypes.

According to this method, the broadband probe signal is emitted into the search zone, the reflected signal is received, the signals from the stationary objects are suppressed by multiplexing and filtering the quadrature components of the received signal at the intermediate frequency, spatial resolution is carried out, changes in the amplitude and phase of the reflected signal caused by movements of the body surface are recorded.

The device contains a microwave generator, a directional coupler, a pulse modulator, an antenna block, a quadrature demodulator, preamplifiers, bandpass filters, multiplexers, multi-channel differentiating-integrating filters, demultiplexers, short-circuit electronic keys, low-frequency amplifiers, a gate pulse generator, a control unit for demultiplexers, modulating pulse generator, ADC, processing and display units.

The disadvantages of the known method and device include low functionality and operational characteristics due to the inability to use for searching living objects and their remains, covered with various types of soil, including increased heterogeneity, such as ruins of buildings, land, snow, etc.

An object of the invention is to expand the functionality and improve operational characteristics by making it possible to search and detect biological objects and their remains, covered with various types of soil, including increased heterogeneity, such as ruins of buildings, land, snow, etc.

The problem is solved in that according to the method of detecting living objects, which consists in emitting a modulated probe signal into the search area, a reflected signal is received, changes in the amplitude and phase of which carry information about the movements, breathing and heartbeat of the desired object, multiply it with two quadrature reference signals, the resulting quadrature signals of the differential frequency at successive times are sent to the inputs of two sets of filters that suppress the constant component caused by by friction from stationary objects, they poll the outputs of the filters, process the generated signals corresponding to the modulation of the probe signal and implement spatial resolution, form the first and second signals that carry information about changes in the amplitude and phase of the reflected signal corresponding to a certain range, extract information about movements, respiration and heartbeat by analyzing these signals, carry out electromagnetic sounding of the soil in the search area of the bombarded biological objects oscilloscopic parallel modulated signal and the reception of signals with right and left circular polarization, reflected from biological objects, while the reflected signal with right circular polarization is gated in time proportional to the depth of the biological object, and the reflected signal with left circular polarization is converted in frequency using the local oscillator voltage, into the quality of which a high-frequency signal shifted in frequency is used, the voltage of the intermediate frequency is isolated, it is multiplied with the reflected signal by the right circle new polarization, emit the harmonic voltage at a stable local oscillator frequency, limit it in amplitude, measure the phase shift between the reflected signals with the right and left circular polarization at a stable local oscillator frequency, compare the measured phase shift with a reference value and decide on the presence of a bioobject based on the results of the comparison in the search and detailed analysis of the signal reflected from it.

The problem is solved in that a device for detecting living objects, including a series-connected high-frequency generator, a directional coupler and a pulse modulator, the second input of which is connected to the first output of the modulating pulse generator, an antenna unit, a quadrature detector, the heterodyne input of which is connected to the second output of the directional coupler , the first and second pre-amplifiers, the input of one of which is connected to the first output of the quadrature demodulator, the first and second floor ow filters, the inputs of which are connected to the outputs of the preliminary amplifiers, the first and second multiplexers, the inputs of which are connected to the outputs of the bandpass filters, and the control inputs through the multiplexer control unit to the second output of the modulating pulse generator, the first and second multichannel bandpass filters, the inputs of which are connected to the outputs of the multiplexers, the first and second demultiplexers, the inputs of which are connected to the outputs of the multi-channel bandpass filters, and the control inputs through the control unit of the demultiplex Rami - with the third output of the modulating pulse generator, the first and second short-circuit electronic keys, the inputs of which are connected to the outputs of the demultiplexers, and the control inputs - with the first output of the digital processing unit, the first and second low-frequency amplifiers, the inputs of which are connected to the outputs of the electronic short-circuit keys, and outputs - with inputs of an analog-to-digital converter, an indication unit connected through a digital processing unit to the output of an analog-to-digital converter is equipped with a polarizer, two amplifiers high frequency drivers, three keys, a frequency shifter, a multiplier, a mixer, an intermediate frequency amplifier, a narrow-band filter, an amplitude limiter, a phase detector and a comparison unit, the antenna unit being made in the form of one transmitting antenna and two receiving antennas, to the output of the pulse modulator in series a polarizer and a transmitting antenna are connected, the output of the first receiving antenna through the first high-frequency amplifier is connected to the radio frequency input of the quadrature demodulator, to the output a second receiving antenna is connected in series with a second high-frequency amplifier, a first key, the second input of which is connected to the first output of the multiplexer control unit, a multiplier, a narrow-band filter, an amplitude limiter, a phase detector, the second input of which is connected to the output of the frequency shifter, a comparison unit, and a third key , the second input of which is connected to the output of the phase detector, and the output is connected to the second input of the display unit, the input of the second pre-amplifier is connected to by the output of the quadrature demodulator and the output of the comparison unit, a frequency shifter, a mixer, the second input of which is connected to the output of the first high-frequency amplifier, and an intermediate-frequency amplifier, the output of which is connected to the second input of the multiplier, are transmitted to the second output of the directional coupler, the transmitting antenna emits a modulated probing signal with linear polarization, the first receiving antenna is susceptible to the reflected signal with right circular polarization, the second receiving antenna sensitive to reflected signals with left-hand circular polarization.

Figure 1 presents the structural diagram of a device that implements the proposed method for detecting living objects. Figure 2 shows a timing diagram explaining the principle of operation of the device.

The device comprises a series-connected high-frequency generator 1, a directional coupler 2, a pulse modulator 3, the second input of which is connected to the first output of the modulating pulse generator 16, a polarizer 19 and a transmitting antenna 20, a series-connected first receiving antenna 21, a first high-frequency amplifier 23 and a quadrature demodulator 5, the heterodyne input of which is connected to the second output of the directional coupler 2, and the first 6.1 and the second 6.2 preliminary connected to the two outputs of it amplifiers directly and through a second switch 28, the second input of which is connected to the output of the comparison unit 34, the first 7.1 and second 7.2 band filters, the first 8.1 and second 8.2 multiplexers, the control inputs of which are connected to the control unit 14, the first 9.1 and second 9.2 multi-channel band filters , the first 10.1 and second 10.2 demultiplexers, the control inputs of which are connected to the control unit 15, the first 11.1 and second 11.2 short-circuit electronic keys, the control inputs of which are connected to the digital processing unit 17, the first 12.1 and second 12.2 bottom frequency amplifiers, analog-to-digital converter 13, digital processing unit 17 and display unit 18, a second receiving antenna 22 connected in series, a second high-frequency amplifier 24, a first key 25, the second input of which is connected to the first output of the multiplexer control unit 14, the multiplier 26, a narrow-band filter 27, an amplitude limiter 32, a phase detector 33, the second input of which is connected to the output of the frequency shifter 29, a comparison unit 34, a third key 35, the second input of which is connected to the output of the phase detector 33 and an indication unit 18 connected in series to the second output of the directional coupler 2 of the frequency shifter 29, a mixer 30, the second input of which is connected to the output of the first high-frequency amplifier 23, and an intermediate-frequency amplifier 31, the output of which is connected to the second input of the multiplier 26. Transmitting antenna 20, the first 21 and second 22 receiving antennas form an antenna unit 4. The transmitting antenna 20 emits a linearly polarized probe signal.

The first receiving antenna 21 is susceptible to reflected signals with a right circular polarization, and the second receiving antenna 22 is susceptible to reflected signals with a left circular polarization.

The device operates as follows.

High-frequency generator 1 generates a probe signal (figure 2, a)

u _s (t) = U _c cos (ω _C t + φ _С ), 0≤t≤T _C ,

where U _C , ω _C , φ _C , T _C - amplitude, carrier frequency and duration of the probe signal; which through a directional coupler 2 enters the first input of the pulse modulator 3, the second input of which from the first output of the modulating pulse generator 16 is supplied with a modulating code M (t) (Fig. 2, b).

At the output of the pulse modulator 3, a phase-shift (QPSK) signal is generated (Fig. 2, c)

u ₁ (t) = U _C cos [ω _C t + φ _K (t) + φ _C ], 0≤t≤T _C ,

where φ _K (t) = {0, π} - manipulated component phase mapping law phase shift keying in accordance with a modulation code M (t), wherein φ _K (t) = const at kτ _E <t <(k + 1) τ _E and can change abruptly at t = kτ _E , i.e. at the boundaries between elementary premises (k = 1, 2, ..., N-1);

τ _E , N - the duration and number of chips that make up the signal duration T _C (T _C = Nτ _E );

which is fed to the input of the polarizer 19, where it acquires plane polarization. The specified signal through the transmitting antenna 20 is emitted in the direction of the earth's surface, under which there may be buried biological objects or their remains.

Detection of the bombarded bioobjects or their remains is carried out by the operator by moving the antenna unit 4 mounted on the rod in front of him left and right and moving forward in a predetermined direction. In this case, it is necessary to ensure that the antenna unit 4 moves parallel to the surface being examined at a fixed distance H (H = 5 ... 10 cm). The speed of movement of the antenna unit 4 is selected depending on the search conditions and should be within 0.1 ... 1.0 m / s. In the search process, it is necessary to alternate the transverse and longitudinal movements of the antenna unit 4 so that after each swing from right to left or left to right, the antenna unit 4 moves forward by a distance of 20 cm (by the size of its linear size). In this case, it is necessary to ensure that the entire checked area is examined, under the surface of which it is possible to find biological objects or their remains. In this case, an electromagnetic field is created in the soil by means of its electromagnetic sounding. When the probing signal reaches a biological object or its remains, it partially reflects to the earth's surface. The reflected signal is picked up by the receiving antennas 21 and 22. In this case, the receiving antenna 21 is susceptible only to the reflected signal with the right circular polarization, and the receiving antenna 22 is only sensitive to the reflected signal with the left circular polarization (counter-clockwise rotation of the electromagnetic field vector). The outputs of the high-frequency amplifiers 23 and 24 produce the following signals:

u _Л (t) = U _Л cos [ω _С ± Δω) t + φ _К (t) + φ ₁ ],

u _P (t) = U _P cos [ω _С ± Δω) t + φ _К (t) + φ ₂ ], 0≤t≤T _С ,

where the indices "P" and "L" refer respectively to signals with right and left circular polarization;

U _L (t), U _P (t) - envelopes of signals with right and left circular polarization;

± Δω - carrier frequency instability caused by incoherent reflection and other destabilizing factors.

The signal u _p (t) from the output of the high-frequency amplifier 24 through the key 25 is fed to the first input of the multiplier 26. In order for the measured phase difference to correspond to the depth h of the bioobject, the multiplier 26 is time-gated using the key 25, to the control input of which the gating pulses arrive formed by the block 14 control multiplexers. The time delay of the pulses is determined by the depth h of the occurrence of biological objects in the ground. When the depth changes, the delay time also changes. The reflected signal u _l (t) from the output of the high-frequency amplifier 23 is fed to the first input of the mixer 30, the second input of which is supplied with the voltage from the output of the frequency shift device 29, used as a local oscillator voltage (Fig.2, g)

u _Г (t) = U _Г cos (ω _Г t + φ _Г ),

where ω _Г = ω _С -ω _пр

At the output of the mixer 30, voltages of combination frequencies are generated. The amplifier 31 is allocated the voltage of the intermediate (differential) frequency (figure 2, d)

u _ave (t) = U _pr (t) cos [(ω _{ave ± Δω) t + φ K (} t) + φ _etc.], 0≤t≤T _C

Where

K ₁ - gear ratio of the mixer;

ω _CR = ω _C -ω _G is the intermediate frequency;

ω _CR = φ _C -φ _G ,

which is fed to the second input of the multiplier 26. At the output of the latter, a harmonic voltage is generated (figure 2, e)

u ₂ (t) = U ₂ (t) cos (ω _Г t + φ _Г + Δφ), 0≤t≤T _C ,

Where

K ₂ - transfer coefficient of the multiplier;

Δφ = φ ₂ -φ ₁ is the phase difference between the reflected signals on the right

and left circular polarization;

which is allocated by the narrow-band filter 27 and is fed to the input of the amplitude limiter 32. A voltage is generated at the output of the latter

u ₃ (t) = U _O cos (ω _Г t + φ _Г + Δφ), 0≤t≤T _C ,

where U _O is the limit threshold;

which is fed to the first input of the phase detector 33, to the second input of which the local oscillator voltage u _g (t) is applied. At the output of the latter, a constant voltage is formed

u _H (t) = U _H cosΔφ,

Where

K ₃ is the transfer coefficient of the phase detector;

proportional to the measured phase shift Δφ. This voltage is compared in block 34 comparison with the reference voltage

u _e (Δφ) = U _e cosΔφ

where Δφ _E is the unchanged phase shift obtained by probing the soil in the absence of biological objects.

The phase shift Δφ is determined by the frequency of the probing signal and the electrical parameters of the soil. This phase shift remains unchanged when probing the soil in the absence of biological objects, since all the quantities determining it remain constant. Therefore, in block 34 of the comparison is stored the reference voltage corresponding to the phase shift Δφ _E when probing the soil in the absence of biological objects.

If u _H (Δφ) ≈u _E (Δφ), then the comparator 34 does not form a constant voltage.

When probing filled bioobjects, signals with right and left circular polarization partially pass through bioobjects having electrical parameters that are different from the ground (high conductivity and permittivity). When an electric wave passes through a bioobject, the phase velocity of the wave propagates. When a plane-polarized electromagnetic wave is reflected from biological objects that are affected by the external magnetic field of the earth, it is divided into two independent components, which in the general case have elliptical polarization with opposite directions of rotation of the electromagnetic field vector. At frequencies of the decimeter range, both components have circular polarization. Both waves propagate and are reflected from bioobjects at different speeds, as a result of which the phase relations between these waves change. This phenomenon is usually called the Faraday effect, due to which the reflected signal experiences the rotation of the plane of polarization. The angle of rotation of the plane of polarization, which is determined by different speeds of propagation and reflection of signals with right and left circular polarization from biological objects, is found from the ratio:

where φ ₁ , φ ₂ are the phase delays of the reflected signals from the right

(rotation of the plane of polarization clockwise) and left

(rotation of the plane of polarization counterclockwise)

circular polarization respectively.

All this leads to a change in the phase shift and the value of the output voltage u _n (Δφ) of the phase detector 33. When u _H (Δφ)> u _Δ (Δφ), a constant voltage is generated in the comparison unit 34, which is supplied to the control input of the key 35, opening it . In the initial state, keys 25, 28 and 35 are always closed. In this case, the output voltage u _n (Δφ) of the phase detector 33 through the public key 35 is supplied to the second input of the display unit 18. Moreover, the fact of registration of the output voltage u _n (Δφ) of the phase measurement indicates the presence of a biological object on this site of soil.

This concludes the process of locating bombarded biological objects or their remains.

At the second stage, the detection of living objects is ensured using the respiratory rate and heart rate, the values of which are from units to tens of hertz. To this end, a constant voltage from the output of the comparison unit 34 is supplied to the control input of the key 28, opening it.

The principle of detecting living objects is that they emit a modulated sounding signal, receive a signal reflected from a biological object, multiply the received and reference signals, extract the difference frequency signal, perform distance selection, select the spectral components of the difference frequency signal caused by respiration and cardiac activity, the signal is multiplied by two quadrature reference signals to extract information about its amplitude and phase, two generated quadrature signals of the difference hour at successive times, they are sent using multiplexers to the inputs of two multichannel band-pass filters to eliminate the constant signal caused by reflections from stationary objects and to accumulate a useful signal, the outputs of the multichannel band-pass filters are polled using demultiplexers with a frequency that ensures the processing of the generated signals in real scale time, they process the signals acting on the outputs of the demultiplexers, corresponding to the type of modulation of the probe signal and realizing spatial resolution (in the case of linearly-frequency-modulated probing signals, this can be a fast Fourier transform), the first and second signals are generated that carry information about changes in the amplitude and phase of the reflected signal corresponding to a certain range, extract information about movements, respiration, and palpitations by analyzing these signals.

The principle of detection of living objects allows the use of various types of modulation of the probe signal, including a pulsed frequency phase-code.

As an example, a sounding signal with phase-code modulation (manipulation) is described.

In addition, to highlight the characteristic spectral components of the received signal and to eliminate information loss, the amplitude spectra of the first and second signals for each specific range are summed.

To improve spatial selection, one subtracts the amplitude spectra of low-frequency signals corresponding to different ranges, for which the spectra are multiplied by weighting factors, which depend on the range, the spectrum with the maximum value is selected, this spectrum is multiplied by the normalizing coefficient and subtracted from the others, the normalizing coefficient is determined for each the operation of subtracting from the condition that the spectral component of the resulting spectrum corresponding to the maximum guide to the subtrahend spectrum.

The reflected signal u _l (t) from the output of the receiving antenna 21 through the high-frequency amplifier 23 is supplied to the quadrature demodulator 5. As a heterodyne signal to this demodulator, a part of the power of the high-frequency generator 1 is supplied through the directional coupler 2. The differential-frequency quadrature signals acting on the outputs of the demodulator 5, enter directly and through the public key 28 to the inputs of the preamplifiers 6.1 and 6.2, respectively, where they are amplified, and then enter the inputs of the bandpass filters 7.1 and 7.2. The lower frequency bandpass bandpass filters is determined by the repetition rate of the probe pulses, and the upper frequency is determined by the spectral width of the probe signal. The signals from the outputs of the bandpass filters 7.1 and 7.2 are fed to the inputs of the multiplexers 8.1 and 8.2. Multiplexers 8.1 and 8.2 provide a sequential time supply of quadrature differential frequency signals to the inputs of multi-channel bandpass filters 9.1 and 9.2. The multiplexer control unit 14 generates a gating pulse, delayed relative to the probing one for a while, which determines the beginning of the range reference, the duration of the gating pulse is equal to or less than the duration of the probing pulse.

Multichannel bandpass filters 9.1 and 9.2 suppress the component of the quadrature signals of the difference frequency caused by reflections from immovable objects and the remains of bioobjects, and a variable component caused by movements, breathing, and heartbeat is isolated. The lower frequency bandwidth of each cell of a multichannel filter, which is determined by the parameters of the filter elements and the input impedance of the low-frequency amplifier, is selected on the order of 0.1 Hz to pass the spectral components caused by respiration.

The signals from the outputs of the multi-channel filters 9.1 and 9.2 are fed to the inputs of the demultiplexers 10.1 and 10.2, performed on standard analog microcircuits, with the help of which the outputs of the cells of the multi-channel bandpass filters 9.1 and 9.2 are polled with the frequency specified by the demultiplexer control unit 15. The sampling frequency of the channels of multichannel bandpass filters 9.1 and 9.2 is chosen so as to provide the possibility of digital processing of the signals acting on the outputs of demultiplexers 10.1 and 10.2 in real time. The signals acting at the outputs of demultiplexers 10.1 and 10.2 are time-stretched copies of the variable components of quadrature signals fed to the inputs of multiplexers 8.1 and 8.2. The outputs of the demultiplexers 10.1 and 10.2 are connected to the inputs of short-circuit elementary switches 11.1 and 11.2, which carry out program-controlled discharge of the cells of multi-channel bandpass filters 9.1 and 9.2 to eliminate transients associated with the action of strong short-term signals arising from the movement of objects in the irradiated zone. The signals from the outputs of short-circuit electronic keys 11.1 and 11.2 are fed to low-frequency amplifiers 12.1 and 12.2 and then to the inputs of the analog-to-digital converter 13, the operation of which is synchronized with the operation of demultiplexers 10.1 and 10.2.

The signal from the output of the analog-to-digital Converter 13 is supplied to the digital processing unit 17. In block 17 of the digital processing, a spectral analysis of quadrature signals corresponding to a given range in a time interval of the order of 10 ... 100 s is performed. The amplitude spectra of the quadrature signals corresponding to each specific range are summed up and the spectral components corresponding to respiration and heartbeats are selected, the amplitude of the selected spectral components is compared with threshold values and a decision is made that the biological object detected in the irradiated zone is a living object that must be quickly removed from soil or debris of a destroyed building. From the output of the digital processing unit 17, the signals enter the display unit 18.

Thus, the proposed method and device in comparison with prototypes and other technical solutions of a similar purpose provide the search and detection of biological objects and their remains, covered with various types of soil, including increased heterogeneity, such as ruins of buildings, land, snow, etc., and also the identification among them of living objects that are subject to rapid salvation.

Moreover, the proposed method and device provide an increase in the reliability of search and detection and resolution in depth when determining the location of biological objects and their remains under a layer of soil. This is achieved through the use of polarization selection and the elimination of the ambiguity of phase measurements, which is ensured by the fact that phase measurements are carried out between the reflected signals with right and left circular polarization, and not between the probing and reflected signals. In this case, the phase shift between the reflected signals with right and left circular polarization is measured at a stable frequency ω _{g of the} local oscillator, which is used as a high-frequency generator after the corresponding frequency shift. Therefore, the process of measuring the phase shift is invariant to the form of modulation (manipulation) of the probe signal. The instability of the amplitude and carrier frequency of the reflected signal arising from incoherent reflection of the signal from biological objects and their remains and other destabilizing factors, which makes it possible to increase the accuracy of measuring the phase shift Δφ and, consequently, the accuracy of determining the location of biological objects and their remains. Thereby expanded functionality and improved operational characteristics of the known method for detecting living objects and devices for its implementation.

Sources of information

1. Kun-Mu Chen, Mirsa D., Chuang H. - R. An.X band microwave Life-Detection System. IEEE Transachions on BME, v. 33, 7, July, 1986.

2. US Patent No. 4958638, A 61 B 5/02.

3. US patent No. 5479120, H 03 K 5/06.

4. RF patent No. 2076336, G 01 S 13/52.

5. Vinokurov V.K. and others. Safety in mountaineering. - M., 1983, p.136-137.

6. RF patent No. 2111119, G 01 S 13/02.

Claims (2)

1. A method for detecting living objects, which consists in emitting a modulated probe signal into the search area, receiving a reflected signal, the amplitude and phase changes of which carry information about the movement, breathing and heartbeat of the desired object, multiplying it with two quadrature reference signals, the resulting quadrature differential frequency signals at sequential times are sent to the inputs of two sets of filters that suppress the constant component caused by reflections from stationary objects, produced filter outputs are polled, the generated signals are processed corresponding to the modulation type of the probing signal and realizing spatial resolution, the first and second signals are generated that carry information about changes in the amplitude and phase of the reflected signal corresponding to a certain range, information about movements, respiration, and heartbeat is extracted by analysis of these signals, characterized in that the electromagnetic sounding of the soil is carried out in the search area of the bombarded biological objects with plane-polarized modulated signal and receiving signals with right and left circular polarization, reflected from the biological object, while the reflected signal with right circular polarization is gated in time proportional to the depth of the biological object, and the reflected signal with left circular polarization is converted in frequency using the local oscillator voltage, as which use a high-frequency signal shifted in frequency by a value equal to the intermediate frequency, isolate the voltage of the intermediate frequency, multiply it from the reflected signal of the right circular polarization, select the harmonic voltage at a stable frequency of the local oscillator, limit it in amplitude, measure the phase shift between the reflected signals with the right and left circular polarization at a stable frequency of the local oscillator, compare the measured value of the phase shift with a reference value and make a decision based on the results of comparison about the presence of a biological object in the search zone and a detailed analysis of the signal reflected from it. 2. A device for detecting living objects, including a series-connected high-frequency generator, a directional coupler and a pulse modulator, the second input of which is connected to the first output of the modulating pulse generator, an antenna unit, a quadrature demodulator, the local oscillator input of which is connected to the second output of the directional coupler, the first and second preamplifiers, the input of one of which is connected to the first output of the quadrature demodulator, the first and second bandpass filters, the inputs of which are the first and second multiplexers, the inputs of which are connected to the outputs of the bandpass filters, and the control inputs through the multiplexer control unit to the second output of the modulating pulse generator, the first and second multichannel bandpass filters, the inputs of which are connected to the outputs of the multiplexers, the first and the second demultiplexers, the inputs of which are connected to the outputs of the multi-channel bandpass filters, and the control inputs through the control unit of the demultiplexers - with the third output of the generator torus of modulating pulses, the first and second short-circuit electronic keys, the inputs of which are connected to the outputs of the demultiplexers, and the control inputs are the first output of the digital processing unit, the first and second low-frequency amplifiers, the inputs of which are connected to the outputs of the short-circuit electronic keys, and the outputs are with the inputs of the analog -digital converter, an indication unit connected through a digital processing unit to the output of an analog-to-digital converter, characterized in that it is equipped with a polarizer, two amplifiers high frequency, three keys, a frequency shifter, a multiplier, a mixer, an intermediate frequency amplifier, a narrow-band filter, an amplitude limiter, a phase detector and a comparison unit, the antenna unit being made as one transmitting antenna and two receiving antennas, to the output of the pulse modulator in series a polarizer and a transmitting antenna are connected, the output of the first receiving antenna through the first high-frequency amplifier is connected to the radio frequency input of the quadrature demodulator, to the output of the second the second receiving antenna, the second high-frequency amplifier is connected in series, the first key, the second input of which is connected to the first output of the multiplexer control unit, a multiplier, a narrow-band filter, an amplitude limiter, a phase detector, the second input of which is connected to the output of the frequency shift device, the comparison unit, and the third key , the second input of which is connected to the output of the phase detector, and the output is connected to the second input of the display unit, the input of the second pre-amplifier is connected through the second key to the second the output of the quadrature demodulator and the output of the comparison unit, a frequency shifter, a mixer, the second input of which is connected to the output of the first high-frequency amplifier, and an intermediate-frequency amplifier, the output of which is connected to the second input of the multiplier, the transmitting antenna emits a modulated probe linear polarized signal.

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