RU2625212C1 - Method of control and registration of movement of vehicles - Google Patents

Abstract

FIELD: radio engineering, communication.

SUBSTANCE: method is implemented by radio frequency tags installed on vehicles, and equipment installed at control and dispatching points. The radio frequency tag comprises a piezoelectric crystal 5, a microstrip antenna 6, electrodes 7, bus bars 8 and 9, a set of reflectors 10. The equipment installed at the control points comprises a high-frequency pulse generator 1, a first 2 and a second 26 power amplifiers, a duplexer 3, a transmit-receive antenna 4, a PMK demodulator 11, multipliers 12 and 13, a narrowband filter 14, a low-pass filter 15, a generator 16 of the pseudo-random sequence, the first 17 and second 19 delay lines, the single time system 18, the adder 20, the registration and analysis unit 21, the first local oscillator 22, the first mixer 23, the first intermediate frequency amplifier 24, the lamp 25. The equipment at the control room comprises a receiving antenna 27, a high frequency amplifier 28, a second local oscillator 29, a second mixer 30, a second intermediate frequency amplifier 31, a complex FMN signal detector 32, a phase doubler 33, a first 34 and second 35 spectrum analyzers, a comparator 36, a threshold block 37, a third delay line 38, a switch 39, a phase divider 40 into two, a narrowband filter 41, a phase detector 42, a recording and analysis unit 43.

EFFECT: reliability of remote control of vehicles increases.

3 dwg

Description

The proposed method relates to the field of management and control of the movement of vehicles, mainly to measuring the time and frequency of movement of objects along constant routes.

Known methods of monitoring and recording the movement of vehicles (ed. Certificate of the USSR No. 746.680; RF patents No. 2.042.211, 2.108.627, 2.130.416, 2.132.042, 2.204.497, 2.267.158, 2.285.933, 2.305 .057, 2.338.263, 2.396.176; US patents Nos. 3,898.984, 4.857.716, 6.148.291, 6.901.331, 7.075.457; French patent No. 2.731.190 and others).

Of the known methods closest to the proposed one is the "Method of monitoring and recording the movement of vehicles" (RF patent No. 2.042.211, G08G 1/123, 1994), which is selected as a prototype.

The known method is based on the formation at the checkpoints along the vehicle's path of high-frequency pulse sequences, converting them into low-frequency pulse sequences that are synchronized with the frequency of the single-time system, and from the resulting pulse sequence form a numerical sequence that reflects the real-time value, which is then converted to in accordance with the specified coding law, indicate, read the received information at the moment t passing vehicles past checkpoints, register the information received and transfer it to the control center, where they analyze the information received.

The disadvantages of this method are the inability to measure time and frequency of movement in the event that the vehicle moves along a route without a schedule or schedule, i.e. belongs to the category of stolen and especially important, as well as the lack of remote control and registration of its movement.

An object of the invention is to increase the reliability of remote monitoring and registration of stolen and especially important vehicles.

The problem is solved in that the method of monitoring and recording the movement of vehicles, consisting, in accordance with the closest analogue, in the formation at the checkpoints along the route of the vehicle high-frequency pulse sequences at the carrier frequency ω _c , reading the received information at the time of passing vehicles by check points, registering the information received and transmitting it to the control room, where it is analyzed, differs from the nearest th analog that is irradiated with high-frequency pulse sequences at the carrier frequency ω _c craft equipped with RFID tags, at the time of their passage past the control points, catch their RF tag is converted high-frequency pulse train to the acoustic wave, allow for distribution of the piezoelectric crystal surface, back reflection, conversion into a complex signal with phase shift keying, the internal structure of which corresponds to the identity the vehicle’s number, and the radiation, receive a complex signal with phase shift keying at the frequency ω _s at the control point, multiply it with a low-frequency voltage proportional to the vehicle identification number M ₁ (t), emit harmonic oscillation at the frequency ω _s , multiply it with the received complex signal with phase shift keying, low frequency emit a voltage proportional to the vehicle identification number M ₁ (t), the modulating code form M ₂ (t), Correspondingly uyuschy number of control points, delaying it for a time τ ₁ equal to the duration Τ ₁ modulating code M ₁ (t), τ ₁ = Τ ₁ form a modulation code M ₃ (t), corresponding to the current time, delaying it for a time τ _2, equal to the duration Τ ₁ and T _{2 of the} modulating codes M ₁ (t) and M ₂ (t), respectively, τ ₂ = Τ ₁ + T ₂ , the modulating codes Μ ₁ (t) + Μ ₂ (t) + Μ ₃ (t ) = Μ _∑ (t), high-frequency pulse sequences are converted in frequency using the frequency ω _{g1 of the} first local oscillator, the voltage of the first intermediate frequency ω _pr1 = ω _s + ω _{g1 is isolated} , manipulator comfort its total phase modulating code M _Σ (t), for amplify power emit ether, to take the control station is converted in frequency by using frequency ω _r2 of the second local oscillator is isolated voltage of the second intermediate frequency _np2 ω = ω _z2 -ω _pr1 , its dual phase voltage is measured the width of the spectrum of the second intermediate frequency and its second harmonic, and if they differ permit further processing of the composite signal with the phase manipulation on the second intermediate frequency ω _np2, divide the phase of the second harmonic of the voltage Ia second intermediate frequency 2ω _np2 into two isolated harmonic oscillation of the second intermediate frequency ω _np2, use it as a reference voltage for the synchronous detection of the composite signal with the phase manipulation on the second intermediate frequency ω _np2, emit a low-frequency voltage proportional to the total modulating code M ₃ (t), record and analyze it.

Structural diagrams of devices implementing the proposed method are presented in FIG. 1, 2 and 3.

The radio frequency tag located on the vehicle contains a piezocrystal 5, on the surface of which an interdigital transducer (IDT) of surface waves (SAW) and a set of 10 reflectors are made. IDT contains two comb systems of electrodes 7, which are connected to each other by buses 8 and 9, connected to a microstrip transceiver antenna 6, also made on the surface of the piezoelectric crystal 5.

The equipment located at the control point contains a series-connected generator 1 of high-frequency pulse sequences, a first power amplifier 2, a duplexer 3, the input-output of which is connected to the transceiver antenna 4, the second multiplier 13, the second input of which is connected to the output of the low-pass filter 15, is narrow-band a filter 14, a first multiplier 12, the second input of which is connected to the output of the duplexer 3, a low-pass filter 15 adder 20, a phase manipulator 25 and a second power amplifier 26, the output of which is connected the second input of the duplexer 3. The first mixer 23, the second input of which is connected to the output of the first local oscillator 22, and the amplifier 24 of the first intermediate frequency, the output of which is connected to the second input of the phase manipulator 25, are connected to the output of the generator 1 of the high-frequency pulse sequences 25. The output of the adder 20 is connected to the input of the first block 21 registration and analysis. The output of the pseudorandom sequence generator 16 through the first delay line 17 is connected to the second input of the adder 20. The output of the single time system 18 through the second delay line 19 is connected to the third input of the adder 20. Multipliers 12 and 13, a narrow-band filter 14 and a low-pass filter 15 form a demodulator 11 complex QPSK signals.

The equipment, located at the control room, contains in series a receiving antenna 27, a high-frequency amplifier 28, a second mixer 30, the second input of which is connected to the output of the second local oscillator 29, a second intermediate frequency amplifier 31, a phase doubler 33, a second spectrum analyzer 35, block 36 comparison, the second input of which through the first analyzer 34 of the spectrum is connected to the output of the amplifier 31 of the second intermediate frequency, the threshold unit 37, the second input of which through the third delay line 38 is connected to its output, key 39, sec second input coupled to an output of the amplifier 31 of the second intermediate frequency phase detector 42 and the second recording unit 43 and analysis. A phase divider 40 into two and a narrow-band filter 41, the output of which is connected to the second input of the phase detector 42, are connected to the output of the phase doubler 33. The phase doubler 33, spectrum analyzers 34 and 35, comparison unit 36, threshold block 37, and the third delay line 38 form Detector of 32 complex QPSK signals.

The proposed method of monitoring and recording the movement of vehicles is implemented as follows.

At the checkpoint, the high-frequency pulse train generator 1 generates high-frequency pulse train

U _c (t) = υ _c * Cos (ω _c t + ϕ _c ), 0≤t≤T _С ,

which, after amplification in the first power amplifier 2 through the duplexer 3, enter the transceiver antenna 4, are emitted by it on the air, irradiate vehicles at the moment they pass the control point, are captured by the microstrip antenna 6 with an RF mark installed on the vehicle, and the IDT is converted into acoustic the wave. The latter propagates over the surface of the piezocrystal, is reflected by a set of reflectors 10, and again is converted by the interdigital system into a complex signal with phase shift keying (PSK)

0≤t≤T_C,

0≤t≤T _C ,

where ϕ _k1 (t) = {0, π} is the manipulated phase component that displays the phase manipulation law in accordance with the modulating code M ₁ (t).

Moreover, the internal structure of the formed complex QPSK signal is determined by the topology of the interdigital transducer, has an individual character and contains all the necessary unique information about the vehicle, for example, identification number, year of manufacture, manufacturer, etc.

As an example in FIG. 1 shows the structure of the modulating code M ₁ (t): 1011010010.

The principle of operation of the RFID tag is based on the fact that the electric fields in space and time created in the piezoelectric crystal 5 by the system of electrodes 7 cause elastic strains that propagate in the crystal in the form of surfactants due to the piezoelectric effect.

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

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

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

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

For direct and inverse conversion of surfactants, various converters are used, the most common among which are interdigital converters (IDT).

An RFID tag is mounted on the vehicle in a place known only to the owner, and serves as a means to detect stolen and especially important vehicles as they pass by checkpoints.

The generated complex QPSK signal U ₁ (t) is emitted by the microstrip transceiver antenna 6 into the ether, received by the transceiver antenna 4 of the control point, and through the duplexer 3 is fed to the first inputs of the first 12 and second 13 multipliers. The second input of the first multiplier 12 is supplied with a reference voltage from the output of the narrow-band filter 14

U _O (t) = υ _o * Cos (ω _c t + ϕ _s ).

The output of the multiplier 12 is formed voltage

where υ _н1 = 1/2 * υ ₁ * υ _о ,

from which the low-pass voltage is allocated by the low-pass filter 15

U _H1 (t) = υ _н1 * _{Cosϕ k1} (t).

This voltage is supplied to the second input of the second multiplier 13. At the output of the latter, voltage is generated

where υ ₂ = 1/2 * υ ₁ * υ _n1 ;

υ _about = 2υ ₂ .

Thus, the reference voltage U _О (t) is formed, which is necessary for the synchronous detection of the received PSK signal U ₁ (t), directly from the received PSK signal U ₁ (t).

This is done using a demodulator 11, consisting of multipliers 12 and 13, a narrow-band filter 14 and a low-pass filter 15. Moreover, this demodulator is free from the phenomenon of "reverse work" inherent in the well-known demodulator of FMN signals (Pistolkors A. A., Sidorov V. I., Kostas D. F. and Travin G. A.).

The low-frequency voltage U _Н1 (t) from the output of the low-pass filter 15 is supplied to the first input of the adder 20.

The pseudo-random sequence generator (PSP) 16 generates a modulating code M ₂ (t) corresponding to the checkpoint number. This code passes through the first delay line 17 to the second input of the adder 20. Moreover, the delay time τ _{1 of} the delay line 17 is selected equal to the duration T _{1 of the} modulating code M ₁ (t) (τ ₁ = T ₁ ). The single time system 18 generates a code M ₃ (t) corresponding to the current time, which, through the second delay line 19, is supplied to the third input of the adder 20. Moreover, the delay time τ _{2 of the} second delay line 19 is selected approximately equal to the duration T ₁ and T _{2 of the} modulating codes M ₁ (t) and M ₂ (t), respectively (τ ₂ = T ₁ + T ₂ ).

The output of the adder 20 is formed by the total modulating code

M _∑ (t) = M ₁ (t) + M ₂ (t) + M ₃ (t),

duration τ _∑ = τ ₁ + τ ₂ .

The voltage U _C (t) from the output of the generator 1 of the high-frequency pulse sequences is simultaneously supplied to the input of the first mixer 23, the second input of which supplies the voltage of the first local oscillator 22

U _Г1 (t) = υ _г1 * Cos (ω _г1 t + ϕ _г1 ).

At the output of the mixer 23, voltages of combination frequencies are generated. The amplifier 24 is allocated the voltage of the first intermediate (total) frequency

where υ _pr1 = 1/2 * υ _c * υ _g1 ;

ω _pr1 = ω _s + ω _g1 - the first intermediate (total) frequency;

ϕ _pr1 = ϕ _s + ϕ _g1 ,

which is supplied to the first input of the phase manipulator 25, to the second input of which a total modulating code M _∑ (t) is supplied from the output of the adder 20. The specified modulating code M _∑ (t) is simultaneously fixed by the registration unit 21.

At the output of the phase manipulator 25, a complex QPSK signal is formed

0≤t≤T_С,

0≤t≤T _C ,

where ϕ _k2 (t) = {0, π} is the manipulated component of the phase, which displays the law of phase manipulation in accordance with the total modulating code M _∑ (t),

which, after amplification in the second power amplifier 26 through the duplexer 3, enters the transceiver antenna 4, is radiated by it, is captured by the receiving antenna 27 of the control room, and through the high-frequency amplifier 28 is fed to the first input of the second mixer 30, the second input of which supplies the voltage of the second local oscillator 29th

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

0≤t≤T_C,

0≤t≤T _C ,

_np2 where υ = 1/2 * υ * υ _{pr1 r2;}

_np2 ω = ω _z2 -ω _pr1 - second intermediate (difference) frequency;

_WP2 cp = φ _pr1 -φ _r2,

which is input to the detector 32 of the complex QPSK signal, consisting of a phase doubler 33, spectrum analyzers 34 and 35, a comparison unit 36, a threshold unit 37, and a third delay line 38. In this case, the output of the doubler 33, which can be used as a multiplier, the two inputs of which the same signal U _PR2 (t) is supplied, produces a harmonic voltage

0≤t≤T_С,

0≤t≤T _C ,

where υ ₄ = 1/2 * υ ² _pr2 ,

in which phase manipulation is already absent, since 2ϕ _k2 (t) = {0, 2π}.

The width of the spectrum Δω _{2 of the} second harmonic of the signal is determined by the duration T _{C of the} signal (Δω ₂ = 1 / T _C ), while the width of the spectrum Δω _{from the} QPSK signal is determined by the duration τ _{e of} its elementary premises (Δω _c = 1 / τ _e ).

It should be noted that the duration T _C QPSK signal is determined as follows:

T _C = N * τ _e ,

where τ _e - the duration of the elementary premises;

N is the number of elementary premises.

The width of the spectrum Δω _{2 of the} second harmonic of the signal is N times smaller than the width of the spectrum Δω _s FMN signal (Δω _s / Δω ₂ = N).

Therefore, when the phase of the QPSK signal is doubled, its spectrum “folds” N times. This circumstance makes it possible to detect and select the QPSK signal even when its power at the receiver input is less than the power of noise and interference.

The spectral width Δω _{from the} FMN signal is measured using a spectrum analyzer 34, and the spectral width Δω _{2 of the} second harmonic of the signal is measured using a spectrum analyzer 35. The voltages U _I and U _II are proportional to Δω _c and Δω _2, respectively, from the outputs of the spectrum analyzers 34 and 35 are fed to two inputs of the comparison unit 36. Since U _I >> U _II , a positive voltage is generated at the output of the comparison unit 36, which exceeds the threshold level U _then in the threshold block 37. The threshold voltage U _then is selected so that it is not exceeded by random noise and simple signals. Upon exceeding the threshold U _pores in the threshold block 37 is formed by a constant voltage which is supplied to the control input 39, opening its key and to the input of the third delay line 38, the delay time τ _e is selected such that it was possible to fix the detected QPSK signal. After this time, the voltage from the output of the delay line is supplied to the second input of the threshold unit 37 and resets its contents to zero. When this key 39 is closed, and the detector 32 is ready to receive the next PSK signal. The voltage U _PR2 (t) from the output of the amplifier 31 of the second intermediate frequency through the public key 39 is supplied to the first (information) input of the phase detector 42.

The harmonic voltage U ₄ (t) from the output of the phase doubler 33 is fed to the input of the phase divider 40 into two, at the output of which a harmonic voltage is generated

0≤t≤T_С,

0≤t≤T _C ,

which is allocated by the narrow-band filter 41, is used as a reference voltage and is supplied to the second (reference) input of the phase detector 42. At the output of which a low-frequency voltage is generated

where υ _Н2 = 1/2 * υ _pr2 * υ ₅ ,

proportional to the total modulating code M _∑ (t). This voltage is fed to the input of block 43 registration and analysis.

Thus, the proposed method in comparison with the prototype provides increased reliability of remote control and registration of stolen and especially important vehicles. This is achieved by using radio frequency tags mounted on vehicles and simplex radio communication between checkpoints and a control room using complex signals with phase shift keying.

The main characteristics of radio frequency tags include the following:

- the power of the generator of high-frequency pulse sequences is not more than 10 mW;

- frequency range - 400-420 MHz;

- range - not less than 50 m .;

- type of emitted signal - harmonic oscillation;

- type of reflected (re-emitted) signal - a complex signal with phase shift keying;

- dimensions of the radio frequency tag - 8 × 15 × 5 mm .;

The main feature of RFID tags are their small size and lack of power supplies.

A big advantage of the proposed method is the use of complex signals with phase manipulation, which have high energy and structural secrecy.

Claims (1)

A method of monitoring and recording the movement of vehicles, which consists in generating at the checkpoints along the route of the vehicle high-frequency pulse sequences at the carrier frequency ω _c , reading the information received at the time the vehicles passed the checkpoints, registering the received information and transmitting it to the control room where it is analyzed, characterized in that it is irradiated with high-frequency pulse sequences on the carrier often those ω _c vehicles equipped with RF tags, when they pass by the control points, pick them up with an RF tag, convert high-frequency pulse sequences into an acoustic wave, provide the opportunity for its propagation over the surface of the piezocrystal, back reflection, conversion into a complex signal with phase shift keying , the internal structure of which corresponds to the identification number of the vehicle, and radiation into the air, receive a complex signal with phase manipulation at a frequency of ω _s at the control point, multiply it with a low-frequency voltage proportional to the identification number M ₁ (t) of the vehicle, isolate harmonic oscillation at a frequency of ω _c , multiply it with a received complex signal with phase shift keying, and isolate a low-frequency voltage proportional to The vehicle identification number M ₁ (t), the modulating code form M ₂ (t), corresponding to the number of control points, delaying it for a time τ ₁ equal to the duration t ₁ modulating present code M ₁ (t), τ ₁ = T _1, is formed modulating code M ₃ (t), corresponding to the current time, delaying it for a time τ _2, equal to the duration T ₁ and T ₂ modulating codes M ₁ (t) and M ₂ (t), respectively, τ ₁ = T ₁ + T ₂ , summarize the modeling codes M ₁ (t) + M ₂ (t) + M ₃ (t) = M _Σ (t), convert high-frequency pulse sequences in frequency using frequency ω _r1 of the first local oscillator is isolated voltage of the first intermediate frequency ω = ω _{c np2} + ω _r1, manipulate it by the total phase modulating code M _Σ (t), for amplify power emit ether, taking and the control station is converted in frequency by using frequency ω _r2 of the second local oscillator and isolated voltage of the second intermediate frequency ω = ω _{np2 pr1} -ω _r2, its dual phase voltage measured spectrum width of the second intermediate frequency and its second harmony and in case of differences allow further processing of the complex signal with phase shift keying at the second intermediate frequency ω _CR2 , divide the phase of the second harmony of the voltage of the second intermediate frequency 2ω _CR2 into two, distinguish harmonic oscillation at the second intermediate th frequency ω _CR2 , use it as a reference voltage for synchronously detecting a complex signal with phase shift keying at the second intermediate frequency ω _CR2 , isolate a low-frequency voltage proportional to the total modulating code M ₃ (t), fix and analyze it.

Images