RU2434299C1 - Sos-system for highways - Google Patents

Abstract

FIELD: information technology.

SUBSTANCE: system has a radio transmitter, a medical and technical support station, and transponders installed on vehicles carrying material valuables, environmentally hazardous and important goods; the radio transmitter is fitted with master generators and a modulation code generator; the medical and technical support station has a selector for a composite signal with composite amplitude modulation and phase keying, spectrum analysers, amplitude limiters, synchronous and phase detectors; and each vehicle transponder has a piezoelectric crystal, a microstrip antenna and a set of reflectors.

EFFECT: high reliability of radio communication with vehicles and medical and technical support stations on highways.

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Description

The proposed system relates to the means of ensuring safety, protection and rescue of people in conditions of heavy traffic on major highways.

Recently, on major highways of Western countries (USA, Germany, South Korea), in order to quickly report a traffic accident on both sides of the highway, systems are installed every kilometer through: SOS telephones of direct radio communication with the nearest medical and technical assistance centers. These systems have autonomous power supplies and are constantly tuned to the wave of the corresponding item.

Most often, there are autonomous systems with solar energy sources (Fig. 1) and sometimes with a system of their orientation to the Sun. The system is installed in the immediate vicinity of the highway on a concrete pillar with a height of 12-15 meters, in the upper part of which there is a permanently fixed KB silicon battery with an area of 0.12 m ² and a maximum electric power of about 10 W at noon, a three-pin radio antenna of the RA and an airtight box GK with a microphone and a call button, inside of which there is a buffer alkaline battery, recharged from the solar battery for night time operation, and a radio transmitter. The solar battery is constantly directed to the South at an angle of 30º to the horizon.

The disadvantages of such a system are:

- the high cost associated with the use of high concrete poles to prevent theft of the solar battery;

- lack of efficiency on cloudy days and low efficiency in the sun-oriented position of the solar battery.

Also known are SOS systems for highways (RF patents Nos. 2,090.777, 2.183.351, 2.242.382, 2.282.897; US patents Nos. 4.753.895, 4.816.893 and others).

Of the known systems, the closest to the proposed one is the "SOS-system for highways" (RF patent No. 2.282.897, G08B 25/12, 2005), which is chosen as the base system.

In the known system, radio communication with the nearest points of medical and technical assistance is carried out using complex signals with combined amplitude modulation and phase shift keying.

However, the potential capabilities of the known system are not fully utilized.

It should be noted that on large highways, a very large traffic flow passes by the SOS system, among which there may be stolen vehicles, collection vehicles, special vehicles carrying material assets, environmentally hazardous and important cargoes. These vehicles require constant monitoring, ensuring the detection and determination of their location and route. This task can be successfully solved by the well-known SOS-system.

An object of the invention is to expand the functionality of the known system by detecting, determining the location and route of movement of stolen vehicles and special vehicles carrying material assets, environmentally hazardous and important goods.

The problem is solved in that the SOS system of radiotelephone communications in emergency situations on large highways, using, in accordance with the closest analogue, solar energy to power the radio transmitter in the daytime and at night and consisting of a multi-cell panel of solar paraboloid concentrators with arsenide in their foci -gallium photodetectors having the ability to convert concentrated solar energy with an efficiency of up to 20% and with a specific power of 200 W / m ² , on the sides of the solar battery photodiodes in cylindrical reflectors are installed, which have the ability to orient the battery in the sun using selsyn with an accuracy of ± 2 °, and the battery itself is placed in a sealed transparent hemisphere, on top of which there is a whip antenna connected to a box in which an alkaline buffer battery, a radio transmitter are placed, a microphone and call buttons, while the boxes are attached to the dividing barrier of the highway at a distance of 0.8 ... 1 km from each other, along the highway in settlements there are m medical and technical assistance, each of which contains a receiving antenna in series, a first high-frequency amplifier, a phase doubler, a second spectrum analyzer, a comparison unit, the second input of which is connected to the high-frequency amplifier output through a first spectrum analyzer, a threshold block, a key, a second input which is connected to the output of the first high-frequency amplifier, a threshold block, a key, the second input of which is connected to the output of the first high-frequency amplifier, the first amplitude limiter and synchronous a torus, the second input of which is connected to the key output, and the output is connected to an audible annunciator and a recording unit, a second amplitude limiter, a phase divider by two, a narrow-band filter and a first phase detector, the second input of which is connected to the output of the first amplitude limiter, and the output is connected to the second input of the registration unit, the radio transmitter is made in the form of series-connected first master oscillator, amplitude modulator, the second input of which is connected Inen with the output of a microphone, a phase manipulator and a first power amplifier, as well as a modulating code generator and a pin antenna, differs from the closest analogue in that it is equipped with a second master oscillator, a second power amplifier, an antenna switch, a second high-frequency amplifier, a second phase detector, two delay lines, a timer, an analog-to-code converter, an adder, an OR logic element and transponders installed on stolen vehicles and special vehicles goods carrying environmental values, environmentally hazardous and important goods, and the second power amplifier, an antenna switch, the input-output of which is connected to the transceiver pin antenna, a second high-frequency amplifier, a second phase detector, the second input of which is connected to the output of the second master oscillator with the output of the master oscillator, the first delay line, an adder, the second input of which is connected to the output of the modulating code generator, and an OR logic element, the second input of which о is connected to the output of the modulating code generator, and the output is connected to the second input of the phase manipulator, an analog-code converter and a second delay line are connected to the timer output, the output of which is connected to the third input of the adder, each transponder is made in the form of a piezocrystal deposited on its surface an aluminum thin-film interdigital transducer associated with a microstrip antenna and a set of reflectors, an interdigital transducer contains two comb systems ctrodes, the electrodes of each of the combs are connected to each other by buses connected to a microstrip antenna.

The structural diagram of the proposed SOS system for highways is presented in figure 2. The structural diagram of the radio transmitter is shown in figure 3. Functional diagram of the transponder shown in figure 4. The structural diagram of the point of medical and technical assistance is presented in figure 5. Timing diagrams explaining the principle of the system are shown in Fig.6 and 7.

The solar battery 1 is a set of solar paraboloidal optical concentrators 2 focused on the arsenide-galium converters located on the rear side of the strips 3. For azimuthal-zenith orientation, photodiodes 4 with reflectors 5 are installed on the sides of the battery 1, controlling selsyn 6.

The battery 1 is installed in a sealed transparent hemispherical cap 7 on a sealed box 8, inside of which there is a buffer alkaline battery 1 and a radio transmitter, and a microphone 9 and call buttons 10 are located on the opposite walls of the box. The pin antenna 11 is installed in the upper part of the hemisphere, and the whole system is fixed on the dividing barrier 12 of the motorway.

The radio transmitter is made in the form of a series-connected first master oscillator 13, an amplitude modulator 14, the second input of which is connected to the output of a microphone 9, a phase manipulator 16 and a second power amplifier 17, serially connected to a second master oscillator 35, a second power amplifier 36, an antenna switch 37, an input - the output of which is connected to the antenna 11, the second high-frequency amplifier 38, the second phase detector 39, the second input of which is connected to the output of the second master oscillator 35, the first back-end line 40 rzhki, an adder 44, a second input coupled to an output of the modulating code generator 15, and a logic element "OR" 45, a second input coupled to an output of the modulating code generator 15, and an output connected to the second input 16 of the phase manipulator.

An analog code converter 42 and a second delay line 43, the output of which is connected to the third input of the adder 44, are serially connected to the output of the timer 41.

The transponder is made in the form of a piezoelectric crystal 46 with an aluminum thin-film interdigital transducer (IDT) deposited on its surface connected to a microstrip antenna 47 and a set of reflectors 51. The interdigital transducer of surface acoustic waves (SAW) contains two comb systems of electrodes 48, bus 49 and 50, which connect the electrodes of each of the combs with each other. Tires 49 and 50, in turn, associated with microstrip antenna 47.

The medical and technical assistance station contains a receiving antenna 18 connected in series, a first high-frequency amplifier 19, a phase doubler 21, a second spectrum analyzer 23, a comparison unit 24, the second input of which is connected to the output of a high-frequency amplifier 19 through a first spectrum analyzer 22, a threshold block 25, a key 26, the second input of which is connected to the output of the first high-frequency amplifier 19, the first amplitude limiter 27 and a synchronous detector 28, the second input of which is connected to the output of the key 26, and the output is connected to the sound CB annunciator 29 and register unit 30. A second amplitude limiter 31, a phase divider 32, a narrow-band filter 33, and a first phase detector 34, the second input of which is connected to the output of the first amplitude limiter 27, and the output is connected to the second input of the recording unit 30, are connected in series to the output of the phase doubler 21.

Phase doubler 21, spectrum analyzers 22 and 23, comparison unit 24, threshold block 25, and key 26 form a detector (selector) 20 of a complex signal with combined amplitude modulation and phase shift keying (AM-FMN).

The system operates in two modes: in a traffic accident mode and in a traffic flow control mode as follows.

When a traffic accident occurs, its participants press button 10 and thereby turn on the power to the radio transmitter. In this case, the first master oscillator 13 generates a high-frequency oscillation (Fig.7 a)

,

,

,

,

where U ₁ , w ₁ , φ ₁ , T ₁ - amplitude, carrier frequency, initial phase and duration of high-frequency oscillations;

which is supplied to the first input of the amplitude modulator 14. The second input of the last modulating function m (t) (Fig.7 b) is output from the microphone 9, which displays the voice message of the victim, which contains information about the details of what happened. At the output of the amplitude modulator 14, a signal with amplitude modulation (AM) is generated (Fig. 7 c)

,

,

,

,

where m (t) is the modulating function that displays the law of amplitude modulation;

which is fed to the first input of the phase manipulator 16. The modulating code M ₁ (t) (Fig. 7 g), which contains an alarm signal (SOS), is supplied to the second input of the latter through the OR gate 45 from the output of the generator 15 of the modulating code 15 , the name of the highway, the number of the separation barrier, which is applied in black on the white surface of the separation barrier, the number of kilometers on which the separation barrier is installed, and other necessary identification data.

At the output of the phase manipulator 16, a complex signal is formed with combined amplitude modulation and phase manipulation (AM-PSK) (Fig. 7 d)

,

,

,

,

where φ _k (t) = {0, π} is the manipulated component of the phase that displays the law of phase manipulation in accordance with the modulating code M ₁ (t) (Fig. 7 g), and φ _к (t) = const at Кτ _э < t <(k + 1) τ _e , and can change abruptly at t = Кτ _e , i.e. at the borders between elementary premises (K = 1, 2, ..., N-1);

τ _e , N - the duration and number of chips that make up the signal of duration T ₁ (T ₁ = N · τ _e ).

This signal after amplification in the power amplifier 17 through the antenna switch 37 enters the transceiver pin antenna 11, is radiated by it at a frequency w ₁ , is picked up by the receiving antenna 18 and through the high-frequency amplifier 19 is fed to the input of the detector (selector) 20, consisting of a doubler 21 phases, spectrum analyzers 22 and 23, comparison block 24, threshold block 25 and key 26. A voltage is generated at the output of the phase doubler 21

,

,

,

,

where U ₄ = ^l / ₂ U ₃ ² ,

As a phase doubler 21, a multiplier can be used, the two signal of which receives the same signal u ₃ (t).

Since 2φ _к (t) = {0.2π}, then in the voltage u ₄ (t) phase manipulation is already absent.

The spectrum width Δf _{2 of the} second harmonic of the signal is determined by the duration T _{1 of the} signal

while the width of the spectrum of the received AM-QPSK signal is determined by the duration τ _{e of} its elementary premises

,

,

those. spectrum width Δf _{2 of the} second harmonic of the signal is N times smaller than the spectrum width Δf _{c of the} input signal

.

.

Therefore, when the phase of the AM-QPSK signal is multiplied by two, its spectrum “folds” N times. This circumstance makes it possible to detect an AM-QPSK signal 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 signal is measured using the spectrum analyzer 22, and the spectrum width Δf _{2 of the} second harmonic of the signal is measured using the spectrum analyzer 23. Voltages U _I and U _II , proportional to Δf _c and Δf _2, respectively, from the outputs of the spectrum analyzers 22 and 23 are supplied to the two inputs of the comparison unit 24.

Since U _I >> U _II , a positive pulse is generated at the output of the comparison unit 24, which is compared with the threshold voltage U _pop in the threshold block 25. The threshold voltage U _{pop is} exceeded only when an AM-FMN signal is detected. When the threshold level U _pores is exceeded, a constant voltage is generated in the threshold block 25, which is supplied to the control input of the key 26, opening it. In the initial state, the key 26 is always closed.

In this case, the received AM-QPSK signal u ₃ (t) from the output of the high-frequency amplifier 19 through the public key 26 is fed to the first input of the synchronous detector 28 and to the input of the first amplitude limiter 27.

At the output of the latter, an QPSK signal is generated (Fig. 7 e)

,

,

,

,

where U ₀ is the limit threshold;

which is fed to the second (reference) input of the synchronous detector 28. As a result of synchronous detection, a low-frequency voltage is generated at the output of the synchronous detector 28 (Fig. 7 g)

,

,

where u _H1 = _^1/2 · U _3, U _0;

proportional to the original modulating function m (t) (Fig.7 b). This voltage is supplied to the first input of the registration unit 30, where it is fixed, and to the input of the audible alarm 29, where an alarm message is played.

The PSK signal u ₅ (t) (Fig. 7 e) from the output of the first amplitude limiter 27 is supplied to the first (information) input of the phase detector 34.

The voltage u ₄ (t) from the output of the phase doubler 21 is simultaneously fed to the input of the second amplitude limiter 31, the output of which is voltage (Fig. 7 h)

,

.

,

.

This voltage is fed to the input of the phase divider 32 into two, the output of which is formed voltage (Fig.7)

,

,

,

,

which is allocated by a narrow-band filter 33 and fed to the second (reference) input of the phase detector 34.

At the output of the phase detector 34, a low-frequency voltage is generated (Fig. 7 k)

,

,

where U _H2 = _^1/2 U ₀ -U _7;

proportional to the modulating code M ₁ (t) (Fig.7 g). This voltage is supplied to the second input of the registration unit 30, where it is fixed.

Therefore, the reference voltage necessary for synchronous detection of the PSK signal is extracted directly from the received AM-PSK signal.

In the control mode of the transport stream, a second master oscillator 35 is turned on, which generates a high-frequency oscillation (Fig. 6 a)

,

,

,

,

where U ₈ , w ₂ , φ ₂ , T ₂ - amplitude, carrier frequency, initial phase and duration of high-frequency oscillations;

which, after amplification in the power amplifier 36, through the antenna switch 37 enters the antenna 11 and is radiated by it at a frequency w ₂ . To exclude harmonic coupling, the ratio of the frequencies w ₁ and w ₂ is chosen fractionally rational.

High-frequency oscillation u ₈ (t) (Fig.6 a) irradiated vehicles passing by the radio transmitter.

In order to prevent theft of the vehicle, the owner, in addition to the anti-theft system, installs a transponder in a place known only to him. The hijacker who has taken possession of the vehicle does not know about the installation of the transponder.

As for special vehicles carrying material assets, environmentally hazardous and important goods, they are a priori supplied with transponders.

A high-frequency oscillation u ₈ (t) at a frequency w _{1 is} captured by a microstrip antenna 47 of a transponder mounted on a vehicle that approaches a radio transmitter and is converted by an interdigital transducer (IDT) into an acoustic wave. The latter propagates along the surface of the piezocrystal 46, is reflected from the reflectors 51 and is again converted into a complex signal with phase shift keying (PSK) (Fig.6 c)

,

,

,

,

where φ _к2 (t) = {0, π} is the manipulated component of the phase that displays the law of phase manipulation in accordance with the modulating code M ₂ (t) (Fig.6 b).

Moreover, the internal structure of the formed complex QPSK signal is determined by the IDT topology, has an individual character and contains information about the vehicle identification number.

The generated complex QPSK signal u ₉ (t) is radiated by the microstrip antenna 47, captured by the antenna 11, and fed through the antenna switch 37 and high-frequency amplifier 38 to the first (information) input of the phase detector 39. At the second (reference) input of the latter, the reference voltage is supplied with a high-frequency oscillation u ₈ (t) (Fig. 6 a) from the output of the master oscillator 35. At the output of the phase detector 39, a low-frequency voltage is generated (Fig. 6 g)

,

,

where U _H3 = _^1/2 · U U _{9 8;}

proportional to the modulating code M ₂ (t) (Fig.6 b). This voltage is supplied to the input of the delay lines 40, where it is delayed by a time τ ₃ equal to the duration τ _{2 of the} modulating code M ₂ (t), and supplied to the second input of the adder 44, to the first input of which a modulating code M ₁ (t) is supplied from the output generator 15 modulating code, duration τ ₁ .

The current time from the output of the timer 41 is fed to the input of an analog-to-digital converter 42, where it is converted to a code that is input to the delay line 43. The delay time τ _{s2 of} the delay line 43 is chosen equal to

τ _s2 = τ ₂ + τ ₃ ,

where τ _s - the duration of the modulating code M ₃ (t).

The delayed code M ₃ (t) is supplied to the third input of the adder 44. At the output of the adder 44, a total modulating code is generated

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

τ _∑ = τ ₁ + τ ₂ + τ ₃ .

The modulating code M _Σ (t) from the output of the adder 44 through the logic element "OR" 45 is fed to the second input of the phase manipulator 16, the first input of which is fed a high-frequency oscillation u ₁ (t) (Fig. 7 a) from the output of the master oscillator 13 through amplitude modulator 14.

At the output of the phase manipulator 16, a complex QPSK signal is formed

,

,

,

,

where φ _к3 (t) = {0, π} is the manipulated component of the phase, which displays the law of phase manipulation in accordance with the modulating code M ₃ (t).

This signal after amplification in the power amplifier 17 through the antenna switch 37 enters the transceiver antenna 11, is radiated by it at a frequency w ₁ , is picked up by the receiving antenna 18 and through the high-frequency amplifier 19 is fed to the input of the detector (selector) 20, and after detection is received the first (information) input of the phase detector 34, the second (reference) input is supplied with a reference voltage

u ₁₁ (t) = U ₁₁ Cos (w ₁ t + φ),

from the output of the narrow-band filter 33.

The output of the phase detector 34 produces a low-frequency voltage

_H3 u (t) = U · cos _{H3 K3} (t),

proportional to the modulating code M ₃ (t). This voltage is detected by the registration unit 30. This voltage determines where, when and which, for example, a stolen vehicle has followed or is currently following this highway in the general traffic stream.

The system provides increased reliability of radio communications with the nearest points of medical and technical assistance. This is achieved by using complex signals with combined amplitude modulation and phase shift keying (AM-PSK) at one carrier frequency w ₁ .

These signals open up new possibilities in the technology of messaging. They allow you to apply a new type of selection - structural selection. This means that there is a new opportunity to separate signals operating in the same frequency band and at the same time intervals. In principle, one can abandon the traditional method of dividing the operating frequencies of the used range between operating SOS systems and selecting them on the receiving side using frequency filters. It can be replaced by a new method based on the simultaneous operation of each SOS system in a given frequency range by means of its structural selection.

Due to the frequency redundancy of broadband radio communication systems, they can successfully operate if there are several narrow-band radio stations in the frequency band of the received AM-FMN signal.

Among other problems, the solution of which largely determines the further progress of radio communications, should include the problem of establishing reliable communication in channels in the presence of a multipath nature of the propagation of radio waves. The presence of multipath propagation of radio waves leads to a distortion of the received signals, which complicates the reception and reduces the reliability of information transmission. Attempts to overcome the harmful effects of multipath have been made for a long time. These include: diversity reception, signal selection by time and angle of arrival, corrective coding, and some other methods. However, all of them do not provide a fundamental solution to the problem.

Due to its good correlation properties, a signal with a complex structure can be “folded” into a narrow pulse, the duration of which is inversely proportional to the used bandwidth. Choosing a frequency band so that the duration of the “convoluted” pulse is shorter than the delay time, it is possible to separately receive pulses arriving at the receiving point in various ways, and by summing their energy, it is also possible to increase the noise immunity of complex AM-FMN signals. Thus, this problem gets a fundamental solution.

From the point of view of detection, complex AM-FMN signals have high energy and structural secrecy.

The energy secrecy of these signals is due to their high compressibility in time and spectrum with optimal processing, which reduces the instantaneous radiated power. As a result, a complex AM-QPSK signal at the receiving point may be masked by noise and interference. Moreover, the energy of a complex signal is by no means small, it is simply distributed over the time-frequency domain so that at each point in this region the signal power is less than the power of noise and interference.

The structural secrecy of complex AM-QPSK signals is caused by a wide variety of their forms and significant ranges of parameter changes, which makes it difficult to optimally or at least quasi-optimally process complex signals of an a priori unknown structure in order to increase the sensitivity of the receiver.

The SOS system provides duplication of the transmission of an alarm message.

If the button 10 is pressed and the microphone 9 is used, then a voice analog message and an automatic digital message containing information about the location of the traffic accident are transmitted.

If only button 10 is pressed, this situation is possible during a traffic accident, then only an automatic digital message is transmitted, and the audible warning device 29 does not work in this case.

Thus, the proposed SOS system for highways, in comparison with the base system and other similar technical solutions for similar purposes, provides for the detection, location and route of the stolen vehicles and special vehicles carrying material assets, environmentally hazardous and important cargoes. This is achieved by using the second mode of operation of the system at a frequency of w ₂ and transponders that are installed on these vehicles.

The main feature of transponders based on surface acoustic waves is their small size, long service life and lack of power sources.

Thus, the functionality of the known system is expanded.

Claims (1)

SOS-system for radiotelephone communications in emergencies on major highways, using solar energy to power the radio transmitter in the daytime and at night, and consisting of a multi-cell panel of solar paraboloid concentrators, the focuses of which are gallium arsenide photodetectors that can convert concentrated solar energy from efficiency to 20% and with a specific power of 200 W / m ² at each side of the solar battery installed in the photodiodes cylindrical reflectors having the possibility ori mount the battery in the sun using selsyn with an accuracy of ± 2 °, and the battery itself is placed in a sealed transparent hemisphere, on top of which there is a whip antenna connected to a box that houses a buffer alkaline battery, radio transmitter, microphone and call buttons, while the boxes are attached to the dividing barrier of the highway at a distance of 0.8 ... 1 km from each other, along the highway in the settlements there are medical and technical assistance points, each of which contains a receiving antenna, a first high-frequency amplifier, a phase doubler, a second spectrum analyzer, a comparison unit, the second input of which is connected through the first spectrum analyzer to the output of the first high-frequency amplifier, a threshold block, a key, the second input of which is connected to the output of the first high-frequency amplifier, the first amplitude limiter and a synchronous detector, the second input of which is connected to the key output, and the output is connected to an audible annunciator and a recording unit, sequentially connect the phase doubler output the second amplitude limiter, a phase divider into two, a narrow-band filter and a phase detector, the second input of which is connected to the output of the first amplitude limiter, and the output is connected to the second input of the recording unit, the radio transmitter is made in the form of series-connected first master oscillator, amplitude modulator, second input which is connected to the output of the microphone, phase manipulator and the first power amplifier, as well as a modulating code generator and a whip antenna, characterized in that it is equipped a second master oscillator, a second power amplifier, an antenna switch, a second high-frequency amplifier, a second phase detector, two delay lines, a timer, an analog-code converter, an adder, an OR logic element and transponders mounted on stolen vehicles and special vehicles carrying material assets, environmentally hazardous and important goods, and the second power amplifier, antenna antenna, is connected in series to the output of the second master oscillator a switch, the input-output of which is connected to the transceiver pin antenna, a second high-frequency amplifier, a second phase detector, the second input of which is connected to the output of the second master oscillator, the first delay line, an adder, the second input of which is connected to the output of the modulating code generator, and a logic element "OR", the second input of which is connected to the output of the modulating code generator, and the output is connected to the second input of the phase manipulator, an analog-to-code converter is connected to the timer output and a second delay line, the output of which is connected to the third input of the adder, each transponder is made in the form of a piezocrystal with an aluminum thin-film interdigital transducer deposited on its surface connected to a microstrip antenna, and a set of reflectors, the interdigital transducer contains two comb electrode systems, the electrodes of each of the combs are connected to each other by buses connected to a microstrip antenna.

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