RU2678109C2 - Method of control of construction state of building or engineering construction structure and device for its implementation - Google Patents

Abstract

FIELD: metrology.SUBSTANCE: invention relates to metrology. Device for monitoring the state of facilities contains radio frequency tags-transponders, signal pre-processing unit, including an analog-to-digital conversion board, communication line - digital bus, converter, computer, display, audio alarm device, indicator labels, reading device or reader. Reader contains a master oscillator, power amplifier, transmit-receive antenna, bandpass filters, multiplier, difference frequency filter, total frequency filter, a registration unit, phase doublers, narrowband filters, phase divider into two phase detector. Each RF tag (transponder) contains a piezoelectric crystal, microstrip transceiver antenna, electrodes, busbars, a membrane and a set of reflectors.EFFECT: technical result is an increase in efficiency and a reduction in energy consumption of the control of the state of the structure of a building or an engineering structure by using radio frequency tags on surface acoustic waves as sensors.2 cl, 3 dwg

Description

The proposed method and device relates to test equipment, namely, to automatic means for continuously monitoring the state of a building structure or an engineering construction structure during its operation, allowing timely detection of excess of permissible deformations of a structure and preventing its destruction.

Known methods and devices for remote monitoring and diagnostics of the state of building structures or civil engineering structures (ed. Certificate of the USSR No. 1.458.647, 1.695.161, 1.733.837, 1.781.555, 1.812.386; RF patents No. 2.037. 797, 2.046.311, 2.049.307, 1.100.866, 2.135.997, 2.230.978, 2.247.958, 2.272.993, 2.276.304, 2.327.105, 2.343.446, 2.369.205, 2.417.369, 2.471.162, 2.576.548; U.S. Patent Nos. 3,170.152, 3.851.521, 4.206402, 4.452.087, 5.894.092; UK Patent 2,260.434; French Patent 2,294.389; Rensky A. B. Guide on tensometric measurement of building structures and materials. - M., 1971. P. 133, 141-155; Kazachek BC and others. Inspection and testing of buildings and armament of -. M .: Higher School, 2006 S. 164 and others).

Of the known methods and devices closest to the proposed is the "Method of monitoring the state of the structure of a building or engineering construction and device for its implementation" (RF patent No. 2.327.105, G01B 7/16, 2006), which are selected as the base object .

Known technical solutions are based on a survey of sensors installed in the places of diagnosis of the structure, the conversion of information received from the sensors from and its transmission to the control point in the form of a computer. The results of the survey of sensors reflect in the form of a visual picture of the current state of the structure on the computer monitor screen.

The main indicators of the state of the building structure and civil engineering construction are the presence and magnitude of the deformation of its constituent elements. Therefore, as a rule, tensometric sensors are used as sensors for monitoring the state of the building structure or civil engineering structure, while the calculated value of the maximum allowable deformation of the structural element on which the sensor is mounted is used as a fixed value for comparing the information received from them.

The advantage of strain gauges are:

- high measurement accuracy (1% in the range of movements (± 0.2; ± 2.0; ± 5.0 mm) and in a wide temperature range - from -40 to + 0.5 ° C;

- high resolution (10 ^-3 mm).

The main disadvantages are:

- rapid aging of strain gauge elements;

- relatively high power consumption;

- low reliability;

- the presence of hysteresis.

High power consumption with the presence of power sources (batteries or accumulators) and the operation of sensors in continuous mode. Since the process, such as deformation of buildings or civil engineering structures, is very slow, and only in extreme situations requires a continuous flow of information, the algorithm of known technical solutions allows you to set the polling interval of the sensors from 5 seconds to 1 month. In most cases, 1-2 measurements per day are enough to monitor objects.

Low reliability of strain gauges is associated with low reliability of power sources and the need for their regular replacement. As a rule, the duration of any power supply does not exceed several days.

High energy consumption and low reliability of strain gauge sensors reduce the effectiveness of well-known technical solutions as elements of the integrated safety of urban infrastructure, especially when operating large, high-rise buildings, mainly office buildings, as well as civil engineering and civil engineering constructions, i.e. for those buildings and civil engineering constructions in which there is a mass congestion of people, since in these cases a timely response to an emergency and ensuring prompt evacuation is especially necessary.

An object of the invention is to increase efficiency and reduce energy consumption by monitoring the state of building structures or civil engineering structures by using radio frequency tags on surface acoustic waves as sensors.

The problem is solved in that the method of monitoring the state of the structure of a building or civil engineering structure, including, in accordance with the closest analogue, interrogating sensors installed in the places of diagnosis of the structure, converting the information received from the sensors and transmitting it to a control point made in the form of a computer with software, where they register and compare e received information with fixed values previously entered into the computer's memory, while forming the conditions the image of the monitored object, repeating its design, is placed on it in places corresponding to the actual location of the sensors, colored indicator labels display the mentioned image with indicator labels on the computer monitor screen, providing a constant connection of the said indicator labels with sensors, as a fixed value for each sensor, the maximum permissible value of the measured parameter obtained by preliminary calculations is used, and the results of a survey of sensors and the results of The data of the last information received from them is reflected in real time through the color of the indicator marks and its change in the conditional image of the object, which is used to judge the health of the sensors and the state of the structure, differs from the closest analogue in that radio frequency tags on surface acoustic waves are used as sensors, each of which has its own identification code, for remote reading of each radio-frequency tag, a probing harmonic oscillation is formed, amplify it by power, radiate in a nd take RFID tags are converted into each RFID tag in the acoustic wave, ensure its spread over the surface acoustic conductor and back reflection is converted reflected acoustic wave in the complex signal with phase shift keying, the internal structure of which is determined by the structure interdigital conversion frequency (ω _c ± Ω _d ) is determined by the carrier frequency ω _s and the frequency deviation ± Ω _d due to the load on the structure, and the phase shift Δϕ is determined by the degree of the formation of the structure on which the radio frequency tag is installed, a complex signal is emitted with phase manipulation into space, captured by a reader, signals with frequencies (ω _s + Ω _d ) and (ω _s -Ω _d ) are extracted, multiplied among themselves, the difference frequency voltage is isolated proportional to the doubled value of the Doppler frequency 2Ω _d , register it and send it to the signal preprocessing unit, and the voltage of the total frequency, double the frequency of the probe harmonic oscillation, isolate it and compare it by phase with the voltage of the total frequency, measure the double value of the phase shift 2Δϕ, register it and send it to the signal preprocessing unit, a complex signal with phase shift keying at the frequency (ω _s + Ω _d ) is multiplied and divided by phase into two, the harmonic oscillation at the frequency is isolated (ω + Ω _{c d),} use it as a reference voltage for the synchronous detection of the composite signal with a phase shift keying in the frequency (ω + Ω _{c d),} emit a low-frequency voltage proportional to the RF identification code IU ki, record it and send a signal preprocessing block.

The problem is solved in that the device for monitoring the state of the structure of the building or engineering construction, containing, in accordance with the closest analogue, a control point characterized by the use of a computer, measuring transducers located in the places of diagnosis of the structure, the associated signal preprocessing unit, including a board of an analog-to-digital converter, means of communication of the signal preprocessing unit with the said computer, made with possibly the method of interrogating measuring transducers, receiving and recording signals containing measuring information, and with the possibility of comparing said information with fixed values previously stored in its memory, and means of visual presentation of information, including a conditional image of a monitored design displayed on a computer monitor screen and colored indicator marks placed on said image in accordance with the placement of the measuring transducers and made with the possibility of reflection I in real time, through my color and its change in operability of the corresponding measuring transducer and the results of comparing the last information received from it, the computer is made with the possibility of simultaneous with changing the color of the label of the display indicator on the screen additional information about the type and design element on which is located the measuring transducer corresponding to the indicated label indicator differs from the closest analogue in that it is equipped with a reader, and in Radio frequency tags based on surface acoustic waves were used as measuring transducers, the reader comprising serially connected to the output of the signal preprocessing unit, a master oscillator, a power amplifier, a duplexer, the input-output of which is connected to a transceiver antenna, a first bandpass filter, a multiplier, and a second input of which through the second bandpass filter connected to the output of the duplexer, and a difference frequency filter, the output of which is connected to the first input of the block and registration and to the first input of the signal preprocessing unit, to the output of the multiplier, a total frequency filter and a phase meter are connected in series, the output of which is connected to the second input of the registration unit and to the second input of the signal preprocessing unit, the first phase doubler is connected in series to the second output of the master oscillator and the first narrow-band filter, the output of which is connected to the second input of the phase meter, the second phase doubler is connected in series to the output of the first band-pass filter, ne each phase divider into two, a second narrow-band filter and a phase detector, the second input of which is connected to the output of the first band-pass filter, and the output is connected to the third input of the registration unit and to the third input of the signal preprocessing unit, each RF tag has its own identification code and is made in in the form of a microstrip antenna, an interdigital transducer, a membrane and a set of reflectors sequentially placed on the surface of the piezocrystal, the interdigital transducer consists of comb electrodes of two systems interconnected buses which are connected to the microstrip transmission-reception antenna.

The structural diagram of a device that implements the proposed method is presented in FIG. 1. A block diagram of a reader (reader) is shown in FIG. 2. A functional diagram of a radio frequency tag (transponder) on surface acoustic waves (SAWs) is shown in FIG. 3.

The device for monitoring the state of the structure of a building or civil engineering structure contains a set of measuring transducers (transponders) 1 connected in series with a reader 11, a signal preprocessing unit 2, including an analog-to-digital converter board 3, a communication line - bus 4, a signal matching device - converter 5 , the control point, made in the form of a computer 6, and associated with the latter monitor 7, and the device 8 audible alarm. The conditional image 9 of the monitored design with the color marks-indicators 10 placed on it is displayed on the monitor screen 7.

The reader (reader) 11 contains a servo generator 12, a power amplifier 13, a duplexer 14, the input-output of which is connected to the transceiver antenna 15, the first band-pass filter 16, the multiplier 18, the second input of which is connected through the second a band-pass filter 17 is connected to the output of the duplexer 14, and a differential frequency filter 19, the output of which is connected to the first input of the registration unit 21 and to the first input of the signal preprocessing unit 2. The output of the multiplier 18 is connected in series to a filter 20 of the total frequency and a phase meter 24, the output of which is connected to the second input of the recording unit 21 and to the second input of the signal preprocessing unit 2. To the second output of the master oscillator 12, a first phase doubler 22 and a first narrow-band filter 23 are connected in series, the output of which is connected to the second input of the phase meter 24.

A second phase doubler 25, a first phase divider 26 into two, a second narrow-band filter 27 and a phase detector 28, the second input of which is connected to the output of the first band-pass filter 16 and the output is connected to the third input of the registration unit 21, are connected in series to the output of the first band-pass filter 16; to the third input of signal preprocessing unit 2.

Each RFID tag 1.i (i = 1, 2, ..., n) contains a microstrip transceiver antenna 30, an interdigital transducer (IDT), a membrane 34 and a set of 35 reflectors, sequentially placed on the surface of the piezocrystal 29. While IDT contains two comb systems of electrodes 31, interconnected by buses 32 and 33. Tires 32 and 33, in turn, are connected to a microstrip transceiver antenna 30.

The proposed control method is carried out by the proposed device as follows.

Carry out the installation of transponders 1.i (i = 1, 2, ..., n) in the most dangerous sections of the structure, subject to the greatest loads. Among them may be reinforced concrete and metal beams, various vertical supports, floor slabs, etc. The aforementioned places are usually determined by the designer of the building or civil engineering construction.

The memory of computer 6 contains the calculated values of the maximum permissible deformation for each controlled structural element of the building or civil engineering structure on which the transponder is installed, as well as information about the type of structure, its location, and other information necessary for making a decision.

For the building (structure) establish constant supervision throughout the entire period of operation. Systems are in constant self-diagnosis mode.

Computer 6, in accordance with a given program, sequentially polls transponders 1.i (i = 1, 2, ..., n). Why the master oscillator 12 generates a harmonic oscillation

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

where U _s , ω _s , ϕ _s , T _s - amplitude, carrier frequency, initial phase and duration of harmonic oscillation,

which, after amplification in the power amplifier 13 through the duplexer 14, enters the transceiver antenna 15, is radiated by it into space, is captured by the microstrip transceiver antenna 30 and converted by the interdigital transducer (IDT) into an acoustic wave that propagates along the surface of the piezoelectric crystal (sound duct) 29, reflected from a set of 35 reflectors and converted IDT into a complex signal with phase shift keying (PSK)

u ₁ (t) = U ₁ cos [(ω _c ± Ω _Д ) t + ϕ _k (t) + Δϕ], 0≤t≤T _s ,

where ± Ω _d is the frequency deviation due to deformation of the building structure or civil engineering structure;

ϕ _k (t) = {0, π} is the manipulated component of the phase, which displays the law of phase manipulation in accordance with the identification code of the radio frequency label;

Δϕ is the phase change caused by the deformation of the membrane 34, which is due to the degree of deformation of the structure.

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

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

- propagation of an acoustic wave over the surface of a piezocrystal (sound duct);

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

For direct and inverse surfactant conversion, an interdigital transducer (IDT) is used, the operation of which is based on the fact that the electric fields in space and time created in a piezoelectric crystal by the electrode system 31 cause elastic strains that propagate in the crystal due to the piezoelectric effect in the form of a surfactant. The resonant frequency of each transponder is determined by the distance between the electrodes. In this case, the transponder is in a free (unstressed) state. When exposed to a load P, the resonant frequency ω _s increases by the value of Ω, which is called the frequency deviation (ω _s + Ω _D ). This occurs due to the deformation of the piezocrystal and a decrease in the distance between the electrodes 31. If the building structure or the civil engineering structure is stretched, the resonant frequency of the transponder decreases (ω _s -Ω _D ). Therefore, the frequency deviation Ω _d can be judged on the loads and deformations of the building structure or civil engineering structure.

IDT is used by standard photolithography methods and by etching a thin metal film deposited on a piezoelectric crystal. The capabilities of modern photolithography make it possible to create IDTs operating at frequencies up to 3 GHz.

A pressure P is applied to the thin membrane 34, causing it to deform. The speed of the surfactant in the region of the membrane 34 changes and the phase of the acoustic wave reflected from the set of reflectors 35 also changes in accordance with the deformation of the membrane 34, which is reflected in the phase shift Δϕ.

The formed complex PSK signal u ₁ (t) is radiated by the microstrip transceiver antenna 30 into the ether, captured by the transmitter transceiver antenna 15 and supplied to the input of bandpass filters 16 and 17 through the duplexer 14. The latter emit complex PSK signals, respectively:

u ₂ (t) = U ₂ cos [(ω _c + Ω _Д ) t + ϕ _k (t) + Δϕ],

u ₃ (t) = U ₂ cos [(ω _c -Ω _Д ) t + ϕ _k (t) + Δϕ], 0≤t≤T _s ,

which are supplied to the inputs of the multiplier 18. At the output of the latter, the voltages of the difference and total frequencies are formed:

u _p (t) = U _p cos2Ω _Д t,

u _Σ (t) = U _r cos (2ω _c t + 2Δϕ), 0≤t≤T _c ,

Where

2ϕ _l (t) = {0.2π}.

The voltage of the differential frequency u _p (t) is allocated by the filter of the differential frequency 19 and is supplied to the first input of the registration unit 21 and to the first input of the signal preprocessing unit 2. The voltage of the total frequency u _Σ (t) is allocated by a narrow-band filter 20 and is supplied to the first input of the phase meter 24.

The harmonic oscillation u _c (t) from the second output of the master oscillator 12 is fed to the input of the first doubler of phase 22, at the output of which a harmonic oscillation is formed

u ₄ (t) = U ₄ cos (2ω _c t + 2ϕ _c ), 0≤t≤T _c ,

Where

which is allocated by a narrow-band filter 23 and enters the second input of the phasemeter 24. The output of the latter produces a voltage

u ₅ (t) = U ₅ cos2Δϕt, 0≤t≤T _c ,

Where

which is fed to the second input of the registration unit 21 and to the second input of the signal preprocessing unit 2.

Complex QPSK signal u ₂ (t) from the output of the band-pass filter 16 is simultaneously fed to the first (information) input of the phase detector 28 and to the input of the second phase doubler. At the output of the latter, a harmonic oscillation is formed

u ₆ (t) = U ₆ cos [2 (ω _c ± Ω _d ) t + 2Δϕ], 0≤t≤T _s ,

Where

2ϕ _k (t) = {0.2π},

which is fed to the input of the phase divider 26 into two. At the output of the latter, a harmonic oscillation is formed

u ₇ (t) = U ₇ cos [(ω _c ± Ω _Д ) t + Δϕ], 0≤t≤T _s ,

which is allocated by the narrow-band filter 27, is used as a reference voltage and is supplied to the second (reference) input of the phase detector 28. As a result of synchronous detection, a low-frequency voltage is generated at the output of the phase detector 28

u _n (t) = U _n cosϕ _k (t), 0≤t≤T _c ,

Where

proportional to the identification code of the radio frequency tag. This voltage is supplied to the third input of the registration unit 21 and to the third input of the signal preprocessing unit 2.

In block 2 of the preprocessing of the voltage signals u _p (t), u _Σ (t) and u _n (t) are converted into digital form using an analog-to-digital converter 3 and transferred to digital bus 4. Converter 5 converts the signals to suitable for processing in computer 6. Computer 6 registers the signals that carry the measurement information, and compares the received data with the limit values previously entered into the memory. Comparison can be carried out, for example, by finding the difference between the mentioned values.

The conditional image 9 of the monitored design with the colored indicator marks 10, corresponding to the transponders 1.i (i = 1, 2, ..., n), is displayed on the display screen 7. The operation of the transponders, the measurements of the frequency deviation Ω _D and the phase shift Δϕ which are within acceptable limits, is reflected in the green color of the indicator label 10. Idle state of the transponder - is displayed in yellow. To reflect transponder readings exceeding the maximum permissible values of frequency deviation Ω _D and phase shift Δϕ, a red indicator is provided.

The computer memory 6 stores the calculated values of the maximum permissible deformation for each specific structural element of the building or civil engineering structure on which the transponder is installed, as well as information about the type of structure, its location and other information necessary for making a decision.

If the information received from the transponder 1 exceeds the maximum permissible value, i.e. when there is a change in the sign of the difference, the computer 6 gives a signal to change the color of the corresponding label indicator 10 and to the audio device 8, which provides the sound signal. At the same time, access is made to the memory of computer 6 and extraction from it of all available information about that element of the building structure on which the excess occurred. The extracted information is displayed on the display screen 7.

The duty officer, in the working area of which display 7 is located, fixes an alarm. The operation of the building is suspended, people are being evacuated, and specialists inspect the structure with which the alarm signal came. After analysis, a decision is made on the further operation of the building.

The system allows you to prevent the occurrence of dangerous deformations in buildings and structures in the early stages and thereby prevent the destruction of the latter, to timely evacuate people of material values.

Constant control and supervision is especially important when operating large, high-rise buildings, mainly office buildings, as well as cultural and leisure facilities, i.e. for those buildings and constructions in which there is a mass congestion of people, since in this case, a quick response to an emergency and ensuring rapid evacuation is especially necessary.

The inventive computer system for monitoring building structures allows round-the-clock automatic monitoring of the state of the controlled structure and displays visual information on the desk of the duty officer, which can be located in the building’s security room, and can be displayed on the police station, the Ministry of Emergencies, or other relevant organization.

Thus, the proposed method and device in comparison with basic objects and other technical solutions of a similar purpose provide increased efficiency and reduced energy consumption for monitoring the state of a building structure or an engineering construction structure. This is achieved by reducing energy consumption and increasing the reliability of sensors, which are used passive transponders (radio frequency tags) on surface acoustic waves (SAWs) connected by a radio frequency channel with a rider (reader).

Surfactant transponders and a reader together with an information processing device (computer) form a radio frequency identification system, the main advantages of which are:

- small dimensions of transponders for surfactants and the absence of power sources (batteries, accumulators);

- long life of radio frequency tags (transponders);

- lack of physical contact between the transponders and the reader;

- high reliability and speed of determining the identification code of the radio frequency tag and its measured deformation parameters of the building structure;

- a large amount of information that passive transponders can carry;

- radio frequency tags (transponders) are almost impossible to fake;

- the radio frequency system can be used even in aggressive environments, and passive transponders can be read by the reader through dirt, paint, steam, water, plastic and wood.

The main characteristics of a radio frequency identification system include the following:

- Reader transmitter power average - not more than 100 MW;

- frequency range - 400 t - 420 MHz, (900-920 MHz);

- range of action - not less than 50 m;

- the number of code combinations - 2 ³² -2 ⁵⁰ ;

- dimensions of transponders 8 × 15 × 5 mm;

- transponder service life - at least 20 years;

- power consumed by the transponder - 0 W.

In addition, the proposed method and device provide an increase in sensitivity in determining deformations of a building structure or an engineering construction due to a 2-fold increase in frequency deviation 2Ω _D and a phase shift of 2Δϕ.

Claims (2)

1. A method for monitoring the state of a building structure or an engineering construction structure, including interrogating sensors installed in the places of diagnosis of the structure, converting the information received from the sensors and transmitting it to a control point, made in the form of a computer with software, where registration and comparison of the received information is carried out with fixed values previously entered into the computer’s memory, a conditional image of the controlled object is repeated, repeating its design, once color markers-indicators are placed on it in places corresponding to the actual location of the sensors, the aforementioned image with indicator marks is displayed on the computer display screen, providing a constant connection of the said indicator marks with sensors, obtained by preliminary calculations as a fixed value for each sensor and the real acceptable value of the measured parameter and the results of the survey of the sensors and the results of the comparison of the last information received from them are reflected in real time through There are indicator labels and its change on the conditional image of the object, which judges the health of the sensors and the state of the structure, characterized in that the sensors use radio-frequency tags on surface waves, each of which has its own identification code, for remote reading of each radio-frequency tag form an encoded harmonic oscillation, amplify it in power, radiate into space, receive radio frequency tags, convert each radio frequency label into acoustic olnu provide its spread over the surface acoustic conductor and back reflection is converted reflected acoustic wave in the complex signal with phase shift keying, the internal structure of which is determined by the structure interdigital conversion frequency (ω _c ± Ω _D) is determined by the carrier frequency ω _c and a frequency deviation of ± Ω _D caused magnitude of the load on the structure, and the phase shift Δφ is determined by the degree of deformation of the structure on which the RF tag is set to radiate a composite signal with a phase ma ipulyatsiey into the space is trapped by the reading device, emit signals with frequencies (ω + Ω _{c d)} and (ω _c -Ω _D) multiplied with each other, separated voltage difference frequency, which is proportional to twice the Doppler frequency 2Ω _D, it is recorded and sent to the signal preprocessing unit, and the voltage of the total frequency, double the frequency of the probe harmonic oscillations, isolate it and compare in phase with the voltage of the total frequency, measure the doubled value of the phase shift 2Δϕ, register it and apravlyayut unit pre-processing, the composite signal with a phase shift keying at a frequency (ω _c + Ω _e) is multiplied and divided in phase two, isolated harmonic oscillation at the frequency (ω _c + Ω _e), use it as a reference voltage for the synchronous detecting a complex signal with phase shift keying at a frequency (ω _s + Ω _D ), a low-frequency voltage proportional to the identification code of the RF tag is isolated, it is recorded and sent to the signal preprocessing unit. 2. The device for monitoring the state of the structure of a building or civil engineering construction contains a control point characterized by the use of a computer, measuring transducers located in the places of structural diagnostics, a signal pre-processing unit associated with them, including an analog-to-digital converter board, communication means of the signal pre-processing unit with said computer configured to interrogate the measuring transducers, receive and register signals, containing measurement information, and with the possibility of comparing said information with fixed values previously stored in its memory, and means of visual presentation of information, including a conditional image of a controllable design displayed on a computer screen and color markers placed on the image in accordance with the location of the measurement converters and made with the possibility of reflection in real time through its color and its change in operability the corresponding measuring transducer and the results of comparing the last information received from it, while the computer is configured to simultaneously display additional information about the type and design element on the screen with the color of the indicator mark, on which the measuring transducer corresponding to the indicator mark is indicated, characterized in that it is equipped with a reading device, and radio frequency tags on surface ac waves, moreover, the reader device contains a master oscillator, a power amplifier, a duplexer, the input-output of which is connected to a transceiver antenna, a first pass filter, a multiplier, the second input of which is connected to the output of the duplexer through a second pass filter, and a difference frequency filter, the output of which is connected to the first input of the registration unit and to the first input of the signal preprocessing unit, to the output of the multiplier the total frequency filter and phase meter are connected in series, the output of which is connected to the second input of the registration unit and to the second input of the signal preprocessing unit, the first phase doubler and the first narrow-band filter, the output of which is connected to the second input of the phase meter, are connected in series to the output the second bandpass filter, the first phase divider into two, the second narrow-band filter and the phase detector, the second input of which is connected inen with the output of the first band-pass filter, and the output is connected to the third input of the registration unit and to the third input of the signal pre-processing unit, each RF tag has its own identification code and is made in the form of a microstrip transceiver antenna, interdigital transducer, and membranes sequentially placed on the surface of the piezocrystal and a set of reflectors, while the interdigital transducer consists of two comb systems of electrodes interconnected by buses, which ineny with microstrip antenna transceiver.

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