RU2254245C1 - Vehicle antitheft device - Google Patents

Abstract

FIELD: transport engineering.

SUBSTANCE: invention relates to facilities designed for preventing unauthorized use and hi-jacking of vehicles. Transmitter is installed on check station, and receiver, actuating unit and passive receiver-responder are mounted on vehicle. Transmitter contains master oscillator, modulating code generator, phase keyer, power amplifier, receive-transmit antenna, high-frequency amplifier, duplexer, phase detector and computer. Receiver contains receiving antenna, high-frequency amplified, two spectrum width meters, frequency doubler, comparator unit, two threshold units, key, ratio-of-two frequency divider, narrow-band filter, phase detector, single-pole valve and store. Actuating unit contains key, ignition coil, two relays, switch, ignition switch, storage battery, side lamps, sound alarm, control switch, three capacitors, thyristor, two resistors, voltage stabilizing diode. Receiver-responder contains piezocrystal, microstrip antenna, electrodes, buses and reflecting plates.

EFFECT: enlarged functional capabilities, possibility of finding hi-jacked vehicle in static deenergized state at parking place, in garage or street.

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Description

The proposed device relates to transport equipment, in particular to devices for preventing unauthorized use or theft of vehicles using radio channels.

Known anti-theft devices for vehicles using radio channels (for example, RF patents Nos. 2006394, 2011574, 2011575, 2021927, 2033352, 2033353, 2033354, 2042548, 2058906, 2061320, 2061321, 2061323, 2180293 and others).

Of the known devices, the closest to the proposed one is "Anti-theft device for a vehicle" (RF patent No. 2058906, 60 R 25/04, 1992), which is selected as the base device.

The specified device provides remote search and detection of a stolen vehicle located in the common traffic stream, and its delay, i.e. when a stolen vehicle is in motion and energized on-board battery.

However, a stolen vehicle cannot be detected if it is in a static state and completely de-energized.

An object of the invention is to expand the functionality of the device by detecting a stolen vehicle when it is in a static de-energized state in a parking lot, in a garage or just outside.

The problem is solved in that the anti-theft device for a vehicle containing a transmitter installed at the control post and consisting of an antenna and a serially connected master oscillator, a phase manipulator, the second input of which is connected to the output of the modulating code generator, and a power amplifier, a receiver mounted on vehicle and consisting of a series-connected receiving antenna, a first high-frequency amplifier, a frequency doubler, a first spectral width meter, b In comparison, the second input, through the second spectral width meter, is connected to the output of the first high-frequency amplifier, the first threshold block, the second key, the second input of which is connected to the output of the first high-frequency amplifier, the first phase detector, the second input of which is connected through a frequency divider on two and a narrow-band filter connected to the output of the frequency doubler, a unipolar valve, a drive and a second threshold block, the first and second relays mounted on the vehicle The first is connected to the closing and opening, and the second to the closing contacts, and the winding of the first of which is connected to the vehicle battery through the ignition switch, and one of the contacts is connected to the ignition coil power supply circuit, time delay unit, thyristor included in the sound power supply circuit signaling device parallel to the switch of the audio signaling device and connected by a control electrode to the output of the time delay unit, the first key connected in series with the winding of the first relay a switch and signal lamps, wherein the first relay is made with an additional make contact, which is included in the control circuit of the time delay unit, the first mentioned contact of the specified relay is made open, and its first make contact is connected between the buzzer and the ignition switch, the control switch is connected between the first the key and the vehicle body, and the winding of the second relay and the make-contact of the second relay connected in series with each other and connected in parallel with the signal The lamps are connected to the battery through the first make contact of the first relay, equipped with a duplexer, a second high-frequency amplifier, a second phase detector and a computer at the control point; moreover, a duplexer is connected to the output of the power amplifier, the input-output of which is connected to the antenna, the second amplifier is high frequency, a second phase detector, the second input of which is connected to the output of the master oscillator, and a computer, and on the vehicle, a passive transponder made on piezo a tall with an aluminum thin-film transducer deposited on its surface and a set of reflectors, the transducer being made in the form of an interdigital structure, plays the role of a delay line on surface acoustic waves and contains two comb electrode systems connected to each other by buses that are connected to a microstrip antenna, also made on the surface of a piezocrystal.

The structural diagram of the transmitter is presented in figure 1. The block diagram of the receiver and the Executive unit is presented in figure 2. The transponder circuit is shown in FIG. Timing diagrams explaining the operation of the device shown in figure 4.

The device comprises a transmitter 1, a receiver 7, an executive unit 27, and a passive transponder 50.

The transmitter 1 consists of a serially connected master oscillator 2, a phase manipulator 4, the second input of which is connected to the output of the modulating code generator 3, power amplifier 5, duplexer 46, the input-output of which is connected to the antenna 6, the second high-frequency amplifier 47, and the second phase detector 48, the second input of which is connected to the output of the master oscillator 2, and the computer 49.

The receiver 7 includes a receiving antenna 8 connected in series, a first high-frequency amplifier 9, a frequency doubler 12, a first spectral width meter 13, a comparison unit 14, the second input of which is connected to the output of a high-frequency amplifier 9 through a second spectral width meter 11, a first threshold block 15 , the second key 16, the second input of which is connected to the output of the high-frequency amplifier 9, the first phase detector 19, the second input of which is connected through two-way frequency divider 17 and the narrow-band filter 18 to the output frequency doubler 12, unipolar valve 20, drive 21 and second threshold block 22. Frequency doubler 12, spectral width meters 11 and 13, comparison unit 14, threshold blocks 15 and 22, key 16, phase detector 19, frequency divider 17, a narrow-band filter 18, a unipolar valve 20, and a drive 21 form a detector 10.

The executive unit 27 consists of an ignition switch 28, a contact 25.1 and a first winding of the ignition coil 24 connected in series to the positive bus of the battery 29. In parallel with the battery 29, the ignition switch 28, the relay coil 25, the first key 23 and the switch 26, the contacts 25.2, 30.1 in series and the signal lamps 31-34 connected in parallel and the relay coil 30 are connected in series. To the positive bus of the battery 29, a terminal 25.2, an audible warning device 35 and a time delay unit 40 are connected in series. A transistor 41 shunted by thyristor 38 and a capacitor 39 are connected to the output of the audible alarm 35. A zener diode 44 is connected to the base circuit of the transistor 41. A resistor 42, a resistor 43, a terminal 25.3, and a capacitor 45 are connected in series to the audible alarm 35.

The transponder 50 is a piezocrystal 51 with an aluminum thin-film transducer deposited on its surface and a set of reflectors 56. Moreover, the transducer is made in the form of an interdigital structure, plays the role of a delay line on surface acoustic waves (SAWs) and contains two comb systems of electrodes 53 connected to each other with another bus 54 and 55, which are connected to a microstrip antenna 52, also made on the surface of the piezocrystal 51.

The principle of remote search and detection in the general transport stream of a stolen vehicle is based on the use of a complex phase-shift (PSK) signal, which is emitted by the transmitter, received and selected by the receiver, detected, accumulated and used to turn on marker lamps, an audible warning device and turn off the engine. Moreover, the included lamps 31-34 and the audible warning device 35 are a sign of detection of a stolen vehicle, and the turned off engine provides a delay of the vehicle and the hijacker. In this case, the transmitter 1 is installed at the control posts or the traffic police cars, and the receiver 7 and the executive unit 27 - on vehicles.

The use of a complex FMN signal makes it possible to apply a new type of selection - structural selection, which provides higher noise immunity and reliability of distinguishing the specified signal from other signals and interference operating in the same frequency band and at the same time intervals.

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

The device operates as follows.

After turning on the transmitter 1 high-frequency oscillation (figure 4, a)

U ₁ (t) = υ _c Cos (ω _c t + φ _c ), 0≤t≤T _s ,

where υ _c , ω _s , φ _s , T _s is the amplitude, carrier frequency, initial phase, and duration of the high-frequency oscillation from the output of the master oscillator 2 to the first input of the phase manipulator 4, to the second input of which the modulating code M ₁ (t) is supplied ( figure 4, b) from the output of the generator 3 of the modulating code. As a result of phase manipulation, the output of the phase manipulator 4 produces an FMN signal (Fig. 4, c)

U ₂ (t) = υ _c · Cos [ω _c t + φ _k (t) + φ _c ), 0≤t≤T _s ,

where φ _k (t) = {O, π} is the manipulated component of the phase that displays the law of phase manipulation in accordance with the modulating code M ₁ (t), and

φ _к (t) = const at К · τ _u <t <(К + 1) · τ _u

and can change abruptly at t = Кτ _u , i.e. on the boundaries between elementary premises (K = 0,1,2, ..., N-1).

τ _u , N is the duration and number of chips that make up the signal of duration T _c (T _c · τ _u ). This signal after amplification in the power amplifier 5 is radiated by the antenna 6 into the air. In this case, the transceiver antenna 6 can be directional, for example parabolic, which ensures irradiation of only the transport stream passing by the control point. The FMN signal U ₂ (t) is captured by the receiving antenna 8 of the vehicle and, through the high-frequency amplifier 9, is fed to the input of the detector 10, consisting of meters 11 and 13 of the spectrum width, frequency doubler 12, comparison unit 14, threshold block 15, key 16, a frequency divider 17 into two, a narrow-band filter 18, a phase detector 19, a unipolar valve 20, a drive 21 and a threshold unit 22. A harmonic voltage is generated at the output of the frequency doubler 12 (Fig. 4, d)

U ₃ (t) = υ _s Cos (2ω _c t + 2φ _s ), 0≤t≤T _c .

Since 2φ _k (t) = {0, 2π}, phase manipulation is already absent in the indicated voltage.

The width of the spectrum Δf _{2 of the} second harmonic is determined by the duration T _{c of the} signal (Δf2 = 1 / Тс), while the width of the spectrum Δf _{c of the} FMN signal is determined by the duration τ _{u of} its elementary premises (Δf _c = 1 / τ _u ), i.e. the width of the spectrum Δf _{2 of the} second harmonic of the signal is N times smaller than the width of the spectrum Δf _{c of the} input signal Δf _c / Δf ₂ = N.

Therefore, when the frequency of the FMN signal is doubled, its spectrum collapses N times. This makes it possible to detect the FMN signal among other signals, noise, and interference even when its power at the receiver input is less than the power of noise and interference.

The width of the spectrum Δf _{c of the} input FMN signal is measured using meter 11, and the spectrum width Δf _{2 of the} second harmonic of the signal is measured using meter 13. Voltage υ ₁ and υ ₂ proportional to Δf _c and Δf _2, respectively, from the outputs of meters 11 and 13 of width spectrum are fed to two inputs of the comparison unit 14. Since υ ₁ >> υ ₂ , a positive voltage is generated at the output of the comparison unit 14, which exceeds the threshold level υ _opop1 in the threshold unit 15. The threshold level υ _opop1 is chosen so that it is not exceeded by random noise. If the threshold level υ _pore1 is exceeded, a constant voltage is generated in the threshold block 15, which is supplied to the control input of the key 16, opening it. Keys 16 and 23 in the initial state are always closed. In this case, the FMN signal U ₂ (t) (Fig. 4, c) from the output of the high-frequency amplifier 9 through the public key 16 is fed to the information input of the phase detector 19. The harmonic voltage U ₃ (t) (Fig. 4, d) the output of the frequency doubler 12 is simultaneously fed to the input of the frequency divider 17 into two, the output of which is generated voltage (figure 4, d)

U ₄ (t) = υ _c Cos (ω _c t + φ _c ), 0≤t≤T _c .

This voltage is allocated by a narrow-band filter 18 and is supplied to the reference input of the phase detector 19. At the output of the latter, a low-frequency voltage is generated (Fig. 4, e)

U _H1 (t) = υ _H1 · Cos ω _k (t), 0≤t≤T _c ,

where U _H1 = _^1/2 K ₁ · υ _c ^2;

K ₁ is the transfer coefficient of the phase detector, corresponding in form to the modulating code M ₁ (t) (Fig. 4,6). The specified voltage is supplied to the input of a unipolar valve 20, the output of which only positive impulses are generated (figure 4, g). These pulses after accumulation in the drive 21 exceed the threshold level υ _pop2 in the threshold block 22. When this level is exceeded, a constant voltage is generated in the threshold block 22, which is supplied to the control input of the key 23, opening it. In this case, the constant voltage of the battery 29 through the closed ignition switch 28, the open key 23 and the closed device switch 26 is supplied to the relay coil 25. The device switch 26 is installed on the vehicle in a place known only to the owner. When the relay 25 is activated, contact 25.1 opens and contacts 25.2 and 25.3 close. Open contacts 25.1 turn off the engine, which causes the vehicle to stop.

The constant voltage of the battery 29 through a closed contact 25.2 is fed to the coil of the relay 30, which is activated and closes the contact 30.1. In this case, the signal lamps 31-34 are installed, installed on the front and rear panels of the vehicle body. At the same time, the voltage of the battery 29 through a closed contact 25.2 is supplied to the audible warning device 35. The operation of the warning lamps 31-34 and the audible warning device is a sign of detection of a stolen vehicle.

In the anti-theft device circuit, the sound alarm and parking lamps already on the vehicle are used.

When the contacts 25.2 and 25.3 are closed, the supply voltage is also supplied to the time delay unit 40, consisting of a transistor 41, resistors 42 and 43, a zener diode 44, and a capacitor 45. The capacitor 45 starts to charge after a certain time interval (5-7 s), which is regulated by a variable resistor 43, the voltage across the capacitor 45 reaches the opening voltage of the zener diode 44, the thyristor 38 is unlocked and the buzzer 35 is activated. To maintain the thyristor 38 in the open state, the charge of the capacitor 37 is used. The buzzer p 35 and marker lamps 31-34 are still working to the detention of the vehicle and the car thief. If the audible alarm 35 is activated, it cannot be turned off only by turning off the ignition switch 28. To turn off the audible alarm 35, it is necessary to turn off the ignition and briefly press the switch 36. This is achieved by locking the thyristor 38 and excludes its re-opening.

At the same time, the probing PSK signal U ₂ (t) irradiates a passive transponder 50, which can be mounted in one or more elements of the vehicle, camouflaged for a specific object, or can be made in the form of a separate miniature device that is placed in a secret place of the vehicle.

The principle of operation of the passive transponder 50 is based on the acoustic processing of the received FMN radio pulse using a delay line on surface acoustic waves (SAWs).

Surface acoustic waves are waves propagating along the surface of solids in a relatively thin surface layer. The propagation velocity of surfactants in crystals is approximately five orders of magnitude lower than the propagation velocity of electromagnetic waves. This means that on a centimeter of the crystal you can fit information that will fill a kilometer-long cable. The high information capacity of SAW devices was first used in delay lines, which allow storing, converting, channeling, diverting and reflecting the signals propagating in them.

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

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

- the propagation of an acoustic wave over the surface of a sound duct and its reflection;

- the inverse transformation of the surfactant into an electrical signal with parameters determined by the internal structure of the interdigital transducer.

For forward and reverse conversion, an interdigital converter is used, the passband of which is much larger than the spectrum width Δf _{c of the} received signal.

An acoustic wave obtained in the transducer propagates along the surface of the piezocrystal 51 and after a while reaches the reflecting plates 56, which reflect the acoustic wave back with a phase determined by the position of the reflecting plates 56 and the amplitude proportional to the reflection coefficient. The surfactant converter converts the reflected acoustic wave back into a radio pulse with phase shift keying (figure 4, and)

U ₅ (t) = υ ₅ · Cos [ω _c t + φ _к2 (t) + φ ₂ ], 0≤t≤T _c ,

where φ _к (t) = {0, π} - is determined by the internal structure of the interdigital transducer (modulating code M ₂ (t)) (Fig. 4, h). As an example, FIG. 4, h shows the interdigital structure for code 101001011. The generated radio pulse U ₅ (t) is radiated by the microstrip antenna 52, received by the antenna 6, and fed through the duplexer 46 and high-frequency amplifier 47 to the information input of the phase detector 48, to the reference input of which a high-frequency oscillation U ₁ (t) is supplied (Fig. 4 a) from the output of the master oscillator 2. A low-frequency voltage is generated at the output of the phase detector 48 (Fig. 4, k)

U _H2 (t) = υ _Н2 · Cosφ _k2 (t), 0≤t≤T _s ,

where U _H2 = _^1/2 K ₁ · υ ₅ · υ _c;

proportional to the modulating code M ₂ (t) (figure 4, h). This voltage from the output of the phase detector 48 is sent to the database of the computer 49 for identification. It is an individual marking of the inspected vehicle, for example, its identification number.

Previously, individual numbers of stolen vehicles are registered by entering them into the computer database 49.

Based on the results of identification, a decision is made and the characteristics of the stolen vehicle are determined.

The main characteristics of the device include the following:

- average transmitter power - not more than 100 mW;

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

- range - not less than 200 m;

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

- type of emitted signal and the signal of the responder - broadband FMN signals (signal base B = 20-100);

- dimensions of the transponder - 8 · 15 · 5 mm;

- transponder service life - at least 20 years;

- power consumed by the transponder - 0 W.

If the stolen vehicle is in a static de-energized state, then transmitter 1 and passive transponder 50 are involved in the operation.

Thus, the proposed device in comparison with the prototype provides not only remote search and detection of a stolen vehicle located in the general traffic stream, and its detention, but also transmission to the control point of alarm information containing information about the stolen vehicle.

In addition, alarm information is transmitted to the control point via radio channel when the stolen vehicle is in a static de-energized state in the parking lot, in the garage or simply on the street with its corresponding exposure to the scanning device.

The main advantage of the automatic teleindication system of a stolen vehicle located in dynamics or statics is the ability to use passive, i.e. small-sized transponder that does not require power sources.

Another advantage is the possibility of combining the functions of re-emission of energy, coding of individual information about a stolen vehicle and the functions of a sensor of any physical quantity in one device with a simple design.

In some cases, the positive property of a passive surfactant transponder for surfactants can be considered low costs for long-term operation (lack of battery and long MTBF).

In addition, in special cases, the reading of individual markings from stolen vehicles can be done covertly, without visible signs of their exposure. Thus, the functionality of the anti-theft device is expanded.

Claims (1)

An anti-theft device for a vehicle, containing a transmitter installed at the control station and consisting of an antenna and a serially connected master oscillator, a phase manipulator, the second input of which is connected to the output of the modulating code generator, and a power amplifier, a receiver mounted on the vehicle and consisting of in series included a receiving antenna, a first high-frequency amplifier, a frequency doubler, a first spectral width meter, a comparison unit, the second input of which is a second spectral width meter is connected to the output of the first high-frequency amplifier, the first threshold block, the second key, the second input of which is connected to the output of the first high-frequency amplifier, the first phase detector, the second input of which is connected through a frequency divider into two and a narrow-band filter with the output of the frequency doubler, unipolar valve, drive and the second threshold block mounted on the vehicle, the first and second relays, made the first with a closing and opening ground, and the second with make contacts, the winding of the first of which is connected to the vehicle’s battery through the ignition switch, and the disconnect is connected to the ignition coil power supply circuit, time delay unit, thyristor connected to the sound signal supply circuit parallel to the sound signal switch and connected by the control an electrode with the output of the time delay assembly, the first key connected in series with the winding of the first relay, a control switch and signal lights, while The second relay is made with an additional make contact, which is included in the control circuit of the time delay unit, and its first make contact is connected between the buzzer and the ignition switch, a control switch is connected between the first key and the vehicle body, and the winding of the second relay and connected in series with each other the make contact of the second relay and the signal lamps connected in parallel are connected to the battery through the first make contact of the first relay, which differs in m, that it is equipped with a duplexer, a second high-frequency amplifier, a second phase detector and a computer at the control station, and a duplexer is connected to the output of the power amplifier, the input-output of which is connected to the antenna, the second high-frequency amplifier, the second phase detector, the second input of which connected to the output of the master oscillator, and a computer, and on the vehicle, a passive transponder made on a piezocrystal with an aluminum thin-film converter deposited on its surface and a set of reflectors, and the transducer is made in the form of an interdigital structure, plays the role of a delay line on surface acoustic waves and contains two comb systems of electrodes connected to each other by buses that are connected to a microstrip antenna, also made on the surface of a piezocrystal.

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