RU2565492C1 - Fire protection system of container basic bearing structure - Google Patents

Abstract

FIELD: fire safety.

SUBSTANCE: invention can be used for fire protection of various objects, including the container basic bearing structures (CBBS) installed in hard-to-reach regions and in the Far North regions, and simultaneous transmission of alarm signals to the remote check point. The system contains the independent alarm and starting fire extinguishing system installed in CBBS, the receiver installed in a check point, the satellite repeaters installed on the spacecrafts (SC) of the satellite communication system and the radio communication channel operating in the simplex mode.

EFFECT: improvement of noise stability and reliability of transmission of alarm signals from CBBS to the check point located at the considerable distance by means of repeaters installed on spacecrafts of the satellite communication system, and increase of dynamic range of input signals and the ratio signal/noise of the receiver of the check control.

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Description

The invention relates to fire fighting equipment, and more particularly to automatic fire alarm systems and controlling fire fighting equipment, and can be used for fire protection of various objects, including container base load-bearing structures (CBNC) installed in hard-to-reach places and in areas Far North, and the simultaneous transmission of alarms to a remote control point.

Known fire protection systems and devices of various objects (ed. St. USSR No. 1261676, 1277159; RF patents No. 2022250, 2024064, 2115451, 2138856, 2170951, 2175779, 2234735, 2242921, 2254614, 2275688, 2344859, 2355037, 2434297 2520429; US patents No. 3786461, 4661320; UK patent No. 2323298; EP patent No. 0360126, 0657728 and others).

Of the known systems and devices closest to the proposed one is the "Autonomous signal-starting fire extinguishing system" (RF patent No. 2520429, G08 17/00, 2013), which is selected as a prototype.

The known system provides increased noise immunity and selectivity of the receiver installed at the control point by suppressing false signals (interference) received via mirror and Raman channels.

However, the known system has limited functionality and does not provide reliable transmission of alarms from the CBSC to the control point, remote over a considerable distance.

In addition, the receiver of the control point contains an autocorrelation demodulator of phase-shift keyed (PSK) signals, consisting of a phase detector and a delay line.

As is known, a phase detector consists of a series-connected multiplier and a low-pass filter, has a small dynamic range of input signals, a limited bandwidth and low slope, which degrade the signal-to-noise ratio at signal levels comparable to the level of the receiver's own noise, which is typical for large the distance between the CBNK and the control point.

In this case, the presence of multiplication products (combinational components) in the phase detector reduces the efficiency of the receiver and requires the installation of appropriate filters that highlight useful information.

All of the above ultimately leads to a decrease in noise immunity and the reliability of the transmission of alarms from the CBNK to the control point, remote at a considerable distance.

An object of the invention is to increase the noise immunity and reliability of the transmission of alarms from the CBSC to a control point remote over a considerable distance by using repeaters located on the spacecraft of the satellite communication system and increasing the dynamic range of the input signals and signal-to-noise ratio of the control point receiver.

The problem is solved in that the fire protection system of the container base bearing structure, containing, in accordance with the closest analogue, an autonomous signal-starting fire extinguishing system located on the container base bearing structure, a receiver located at a remote control point, and a radio channel installed between them and working in simplex mode, while the autonomous signal-starting fire extinguishing system contains a registration unit, a heat starter connected in series, a current nickname with a pyrotechnic activator and a time relay, which is connected to the signal device through a normally closed contact and is additionally connected to the actuator through a normally open contact, while the thermal starter and the current source with the pyrotechnic activator are structurally combined and enclosed in a housing, the thermal starter is made in a spring-loaded rod installed with the possibility of translational movement and interaction with the pyrotechnic activator of the current source, and from the end sections of the spring-loaded stem is located with the possibility of protruding from the housing and is equipped with a latch made of material with a thermomechanical shape memory, the current source includes a shell with a solid-state block made of a solid-salt non-separate electrochemical composition based on a lithium alloy and disulfide iron, the signal device is made in the form of a signal transmitter to a remote receiver, while the signal transmitter is made in the form serially connected master oscillator, n-tap delay line, phase inverters included in the m-taps of the n-tap delay line, adder, (n + 1) -th input of which is connected to the output of the master oscillator, power amplifier and transmitting antenna, and the receiver is made in the form of series-connected receiving antenna, high-frequency amplifier, first mixer, the second input of which is connected through the first local oscillator to the output of a sawtooth voltage generator, the first intermediate frequency amplifier, correlator, and second of the second block, the second key, the second input of which is connected to the output of the first intermediate frequency amplifier, the phase doubler, the second spectrum analyzer, the comparison unit, the second input of which is connected through the first spectrum analyzer to the output of the second key, the first threshold block, the second input of which is through the first line the delay is connected to its output, the first key, the second input of which is connected to the output of the second key, and the second delay line, connected in series to the output of the sawtooth voltage generator of the second hetero on the second mixer, the second input of which is connected to the output of the high-frequency amplifier, and the second intermediate-frequency amplifier, the output of which is connected to the second input of the correlator, the control input of the sawtooth voltage generator is connected to the output of the first threshold block, the frequencies ω _r1 and ω _{r2 of the} first and second local oscillators spaced at twice the intermediate frequency

ω _r2- ω _r1 = ₂ ω _up

selected symmetrical with respect to the carrier frequency ω _{from the} received signal

ω _c -ω _r1 = ω _r2 -ω _c = ω _up

and are tuned synchronously, differs from the closest analogue in that it is equipped with repeaters located on the spacecraft of the satellite communication system, the receiver located at the control point is equipped with a phase inverter, three adders and two envelope detectors, and the first adder is connected in series to the output of the second delay line , the second input of which is connected to the output of the first key, the first envelope detector and the third adder, the output of which is connected to the input of the registration unit, to the output of the second line behind erzhki phase inverter connected in series, a second adder, a second input coupled to an output of the first switch and a second envelope detector, whose output is connected to a second input of the third adder.

In FIG. 1 is a structural diagram of an autonomous fire extinguishing signal-starting system. In FIG. 2 shows a graph of the voltage across the output contacts of the current source. In FIG. 3 shows a power source structurally integrated in a single housing with a pyrotechnic activator and a thermal actuator of electrical action. In FIG. 4 shows a power source structurally integrated in a single housing with a pyrotechnic activator and thermal shock actuator. In FIG. 5 is a structural diagram of a transmitter. In FIG. 6 is a block diagram of a receiver. In FIG. 7 is a frequency diagram illustrating the formation of additional receive channels. In FIG. Figure 8 shows the relative position of the CBNK, a satellite repeater of a control point (PC).

The autonomous fire alarm system includes a heat starter 1 connected in series, a current source 2 with a pyrotechnic activator 3, and a time relay 4, which is connected to the signal device 5 via a normally closed contact and is additionally connected to the actuator 6 through a normally open contact.

The thermal starter 1 and the current source 2 with the pyrotechnic activator 3 are structurally combined and enclosed in a single housing 7 made of an insulating material. As an insulating (non-conductive) and non-magnetic material in the manufacture of system elements, plastic materials, materials based on glass or organ fiber can be used. The thermal starter 1 is made in the form of a cylindrical rod 8 installed in the housing 7. The rod 8 is equipped with a translational displacement drive, which is a compression spring 9 mounted coaxially on the rod 8 in its middle part. The end portion 10 of the spring-loaded stem 8 is arranged to protrude from the housing 7 and has a figured groove for interacting with a heat-sensitive latch 11, made in the form of a staple with a diameter of about 20 mm from a material with a thermomechanical shape memory, for example titanium nickelide.

The thermal starter 1 has the ability to interact with the pyrotechnic activator of the current source 2 in two different ways, differing in their structural embodiments.

The thermal actuator 1 of the electrical action shown in FIG. 3, is equipped with a solenoid 12 with a central axial channel 13, the terminals 14 of which are electrically connected to the pyrotechnic activator 3. In this case, the pyrotechnic activator 3 is made in the form of an incandescent bridge 15, electrically connected to the terminals 14, and an initiating substance 16 weighed on it. In addition, , the second end section 17 of the spring-loaded rod 8 is magnetized (in the drawings, the corresponding poles of the permanent magnet are denoted by the letters S and N) and mounted to move inside the central axial channel 13 of the solenoid 12.

The thermal impact starter 1 shown in FIG. 4, characterized in that the second end portion 17 of its spring-loaded rod 8, facing the pyrotechnic activator 3, is equipped with a conical striker 18. In this case, the pyrotechnic activator 3 is made in the form of an igniter and a weight of the initiating substance 16 and the capsule 19. The current source 2 is a device constant-readiness power based on a thermal chemical current source of backup type, which is a structure in a sealed shell 20 with a solid state checker 21 made of a solid-salt, non-detachable electrochem a lithium alloy and iron disulfide based composition. In this case, the solid-state checker 21 is in direct contact with the weighed portion of the initiating substance 16 of the pyrotechnic activator 3, which is also mainly located in a sealed shell 20. The current source 2 has electrical leads 22, which are normally connected to the input contacts of the time relay 4.

The time relay 4 is an electronic on-off time switch, which is electrically connected through a normally closed output contact to a signal device 5 and simultaneously electrically connected to an actuator 6 through a normally open output contact.

The actuator 6 is mainly a fire extinguishing aerosol generator with an electric trigger, for example a squib, which, in fact, is connected to a normally open contact of the time relay 4.

The signal device 5 is mainly a transmitter of a radio signal to a remote receiver.

The transmitter contains serially connected master oscillator 23, an n-tap delay line 24.i (i = 1, 2, ..., n), phase inverters 25.j (j = 1, 2, ..., m) included in m taps n- a delay branch line 24.i, an adder 26, a power amplifier 27, and a transmitting antenna 28.

The receiver includes a receiving antenna in series, a high-frequency amplifier 30, a first mixer 31, the second input of which is connected through the first local oscillator 33 to the output of the sawtooth voltage generator 32, and the first intermediate frequency amplifier 34 connected in series to the output of the sawtooth voltage generator 32 of the second local oscillator 46, a second mixer 47, the second input of which is connected to the output of the high-frequency amplifier 30, a second intermediate-frequency amplifier 48, a correlator 49, the second input of which is connected to the output a first intermediate frequency amplifier 34, a second threshold unit 50, a second key 51, the second input of which is connected to the output of the first intermediate frequency amplifier 34, a phase doubler 37, a second spectrum analyzer 38, a comparison unit 39, the second input of which is connected to the first spectrum analyzer 36 the output of the second key 51, the first threshold block 40, the second input of which through the first delay line 41 is connected to its output, the first key 42, the second input of which is connected to the output of the second key 51, the second delay line 44, the first adder 53, the second input d is connected to the output of the first key 42, the first envelope detector 55, a third adder 57 and register unit 45. The phase inverter 52, the second adder 54, the second input of which is connected to the output of the first key 42, and the second envelope detector 56, the output of which is connected to the second input of the third adder 57, are serially connected to the output of the second delay line 44. The control input of the sawtooth generator 32 is connected to the output the first threshold block 40.

Spectrum analyzers 36 and 38, a phase doubler 37, a comparison unit 39, a first threshold block 40, and a first delay line 41 form a detector (selector) 35 of the phase-shift (PSK) signals.

The second delay line 44, the bass reflex 52, the adders 53, 54 and 57, the envelope detectors 55 and 56 form the demodulator 43 of the PSK signals.

The fire protection system of the container base bearing structure operates as follows.

The specified system contains an autonomous signal-starting fire extinguishing system installed on the CBNK, a receiver installed on the control point, satellite transmitters placed on the spacecraft (SC) of the satellite communication system, and a radio communication channel operating in simplex mode (Fig. 8).

Uninhabited CBNCs are installed mainly in remote, inaccessible and rarely visited places, for example, in the Far North. They should provide the possibility of operating especially important electronic equipment of various functional purposes, located inside them, in emergency situations of natural and man-made nature.

To transmit information to a remote control point, satellite transmitters are used, which are located on the satellite of a satellite communications system, for example, Gonets-D1 m.

The main elements of an autonomous fire extinguishing alarm and start-up system are delivered to the CBNK in assembled form and in cocked position, are installed stationary at the place of the most likely fire occurrence. After installing the fire extinguishing system, all fuses are removed, including from the rod 8 (not shown in the drawing), and it is put into standby mode.

When a fire occurs and the temperature rises in the area of the heat-sensitive latch 11 to the activation threshold (72 ° C), a martensitic transformation occurs in its material, accompanied by the restoration of the predefined shape of the staple, the latter unclenches, restoring its shape, and releases the end portion 10 of the rod 8. Stock 8 under the influence of the spring 9 of the drive (its translational motion) begins to move down. Together with the rod 8, its second end section 17 also moves. Further, a pyrotechnic activator 3 with a thermal actuator 1 of electric action or a pyrotechnic activator 3 with a thermal actuator 1 of shock action can be implemented.

In the first case, the spring-loaded rod 8 interacts with the pyrotechnic activator 3 by means of a magnetized second end portion 17, which moves inside the central axial channel 13 of the solenoid 12 and generates a current pulse transmitted through electric to the water 14 to the glow bridge 15 of the pyrotechnic activator 3. The required value of the electric pulse is 0.5-1.0 A, duration 1-10 ms.

In the second case, the spring-loaded rod 8 interacts with the pyrotechnic activator 3 by means of a conical striker 18, which strikes the capsule 19. In both cases, the ignition portion of the initiating substance 16 ignites, which in a short time melts the solid-salt electrochemical composition of the solid-state checker and puts the current source 2 into the generating state current of a given value. As the graph shows (Fig. 2), a short activation time (t _o ≤1c) allows the use of current source 2 in tools and devices with a short time to bring into working condition. During the time period t ₁ , the signaling device 5 is turned on and functioning. The duration of the time period t _{1 is} provided by the time relay 4, is set during the installation of the fire extinguishing system and depends on the schedule and emergency plan for the guarded object. During the specified period of time, the normally closed electrical contact of the output of the time relay 4 with the signal device 5 is necessarily maintained, which ensures the transmission of the radio signal to the remote receiver.

For this, the master pulse 23 generates a radio pulse

u _c (t) = U _c Cos (ω _c t + φ _c ), 0≤t≤τ _e ,

where U _c , ω _c , φ _c , τ _e is the amplitude, carrier frequency, initial phase, and duration of the radio pulse.

The generated radio pulse from the output of the master oscillator 23 is fed to the input of the multi-tap delay line 24.i (i = 1, 2, ..., n) and to the (n + 1) -th input of the adder 26. In the multi-tap delay line 24.i the delay time between the nearest adjacent taps is equal to the duration of the radio pulse τ _e (τ _zi = τ _e , i = 1, 2, ..., n). In some taps of the delay line, phase inverters 25.j are included (j = 1, 2, ..., m), which provide 180 ° phase rotation at their outputs (in accordance with the identification code M (t) of the fire safety object). At the output of adder 26, a complex signal with phase shift keying (QPSK) is generated in the form of the algebraic sum of radio pulses from all taps of the delay line 24.i (i = 1, 2, ..., n) and from the output of the master oscillator 23

u ₁ (t) = U _c · Cos [ω _c t + φ _к (t) + φ _с ], 0≤t≤T _c ,

where φ _к (t) = {0, π} is the manipulated phase component that displays the phase manipulation law in accordance with the modeling code M (t), and φ _к (t) = const for Кτ _э <t <(К + 1) τ _e and can change abruptly at t = Kτ _e , i.e. at the boundaries between elementary premises (radio pulses) (K = 1, 2, ..., n);

τ _e , n is the duration and number of elementary packages (radio pulses) of which a signal of duration T _s is composed (T _c = τ _e · n).

This signal, after amplification in the power amplifier 27, enters the transmitting antenna 28, is radiated by it, is captured by the satellite repeater of the nearest spacecraft of the Gonets-D1M satellite communication system. The orbit of the spacecraft is circular, altitude 1,500 km, inclination 82.5 degrees. Ballistic construction of the orbital grouping - 12 spacecraft in 4 planes. Frequency range 200-300 MHz. The number of channels on one spacecraft: “Up - 14”, “Down - 2”. The relay signal with preserving the phase relationships is captured by the receiving antenna 29 installed at the control point, and through the high-frequency amplifier 30 it is supplied to the first inputs of the first 31 and second 47 mixers, the second inputs of which are supplied with voltages of the first 33 and second 46 local oscillators of linearly varying frequency, respectively :

u _r1 (t) = U _r1 Cos (ω _r1 t + πγt ² + φ _r1 ),

u _r2 (t) = U _r2 Cos (ω _r2 t + πγt ² + φ _r2 ),

- скорость изменения частот гетеродинов 33 и 36 в заданном диапазоне частот Df;Where

- the rate of change of the frequencies of the local oscillators 33 and 36 in a given frequency range Df;

Tp is the period of perestroika.

The frequencies ω _r1 and ω _{r2 of the} local oscillators 33 and 46 are spaced apart by a double value of the intermediate frequency 2 ω _up (Fig. 7)

ω _r2 -ω _r1 = 2ω _up ,

selected symmetrical with respect to the carrier frequency ω _{from the} received signal

ω _c -ω _r1 = ω _r2 -ω _c = ω _up

and rebuild synchronously.

This circumstance leads to a doubling of the number of additional receiving channels, but creates favorable conditions for their suppression due to the correlation processing of channel voltages.

It should be noted that the search for complex QPSK signals in a given frequency range Df is performed using a sawtooth voltage generator 32, which linearly changes the frequencies ω _r1 and ω _{r2 of the} local oscillators 33 and 46.

At the output of the mixers 31 and 47, voltages of combination frequencies are generated.

Amplifiers 34 and 48 are allocated voltage intermediate frequency:

u _up1 (t) = U _up1 · Cos [ω _up t + φ _к (t) -πγt ² + φ _up1 ],

u _up2 (t) = U _up2 · Cos [ω _up t-φ _к (t) + πγt ² + φ _up2 ], 0≤t≤T _c.

;Where

;

ω _up = ω _c -ω _r1 = ω _r2 -ω _c is the intermediate frequency;

ω _up1 = φ _s -φ _r1 , φ _up2 = φ _r2 -φ _s ,

which are complex signals with combined phase shift keying and linear frequency modulation (FMN-LFM).

These voltages are supplied to two inputs of the correlator 49, at the output of which a voltage U is generated proportional to the correlation function R (τ), which is compared with the threshold voltage U _pore1 in the threshold block 50.

The threshold level U _{pore is} exceeded only at the maximum output voltage Umax of the correlator 49 (U _max > U _pore1 ).

Since the channel voltages u _up1 (t) and u _up2 (t) are formed by the same useful QPSK signal received by the main signal at a frequency ω _s (Fig. 7), there is a strong correlation between channel voltages. The output voltage of the correlator reaches the maximum value of U _max and exceeds the threshold level of U _por1 in the threshold block 50 (U _max > U _por1 ).

It should also be noted that the correlation function R (τ) of complex QPSK signals has a remarkable property: it has a pronounced main lobe and a low level of side lobes.

When the threshold level U _pore1 is exceeded, a constant voltage is generated in the threshold block 50, which is supplied to the control input of the key 51 and opens it. In the initial state, the key 51 is always closed. In this case, the voltage U _up1 (t) from the output of the first intermediate frequency amplifier 34 through the public key 51 is fed to the input of the detector (selector) 35 QPSK signal, consisting of a phase doubler 37, spectrum analyzers 36 and 38, comparison unit 39, and threshold block 40 and the first delay line 41.

A voltage is generated at the output of the phase doubler 37

u ₂ (t) = U ₂ · Cos [2ω _up t-2πγt ² + 2φ _up ], 0≤t≤T _c ,

,Where

,

in which phase manipulation is already absent.

, тогда как ширина спектра входного ФМн-сигнала определяется длительностью τ_э его элементарных посылок

, т.е. ширина спектра второй гармоники сигнала в n раз меньше ширины спектра входного сигнала

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

, while the width of the spectrum of the input QPSK signal is determined by the duration τ _{e of} its elementary premises

, i.e. the width of the spectrum of the second harmonic of the signal is n times smaller than the width of the spectrum of the input signal

.

Therefore, when the phase of the QPSK signal is doubled, its spectral width “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 width of the spectrum Δf _{c of the} input QPSK signal is measured by the spectrum analyzer 36, and the spectrum width Δf _{2 of the} second harmonic of the signal is measured using the spectrum analyzer 38. The voltage U ₁ and U ₁₁ proportional to Δf _c and Δf _2, respectively, from the outputs of the spectrum analyzers 36 and 38 are supplied to the two inputs of the comparison unit 39. Since U ₁ >> U ₂ , a positive voltage is generated at the output of the comparison unit 39, which exceeds the threshold level U _por2 in the threshold block 40. The threshold level U _por2 is selected so that it is not exceeded by random noise. When the threshold voltage U _pore2 is exceeded, a constant voltage is generated in the threshold block 40, which is supplied to the control input of the switch 42, opening it, to the input of the delay line 41 and to the control input of the sawtooth voltage generator 32, turning it off. The key 42 in the initial state is always closed.

When the frequency tuning of the sawtooth generator 32 is stopped, the following voltages are allocated by the amplifiers 34 and 48 of the intermediate frequency:

u _up3 (t) = U _pr1 · Cos [ω _up t + φ _к (t) + φ _up1 ],

u _up4 (t) = U _pr2 · Cos [ω _up t-φ _к (t) + φ _up2 ], 0≤t≤T _C

At the output of the phase doubler 37, in this case, a harmonic voltage

u ₃ (t) = U ₂ Cos (2ω _up t + 2φ _up1 ), 0≤t≤T _c

The voltage U _up3 (t) from the output of the first intermediate frequency amplifier 34 through the public keys 51 and 42 is simultaneously fed to the input of the second delay line 44 and to the first input of the first 53 and second 54 adders, to the second inputs of which the same _QPSK signal U _up3 (t) at an intermediate frequency from the output of the delay line 44, delayed by a time of τ _s , equal to the duration τ _{e of the} chips (τ _s = τ _e ), and to the second input of the second adder 54 a complex PSK signal of intermediate frequency U _up3 (t) is received 180 ° phase-shifted in the bass reflex 52.

Consequently, the first 53 and second 54 adders receive unstoppable and delayed by the duration τ _{e of} elementary packages PSK signals of intermediate frequency. In these adders, the unstopped and delayed QPSK signals of the intermediate frequency are summed in phase and out of phase, i.e. On one of the adders, the PSK signals are added, and on the other, they are subtracted. If the amplitudes of the delayed and uncontrolled QPSK signals are equal, at the output of the first 53 and second 54 voltage combiners, they either double or become equal to zero, i.e. the phase relations between the symbols (elementary premises) of the modeling code M (t) are replaced by amplitude ones. From the outputs of the first 53 and second 54 adders voltage supplied to the inputs of the detectors 55 and 56 of the envelope of opposite polarity, respectively. The detected signals are fed to two inputs of the third adder 57.

Due to the fact that the signals are separated in time and have different polarities, a differential video signal is generated at the output of the third adder 57. A positive video signal corresponds to a phase difference of delayed and uncontrolled chips equal to zero, and a negative signal corresponds to a phase difference of 180 °.

The circuit, consisting of envelope detectors 55, 56 and the third adder 57, operates as a maximum selection circuit. This does not degrade the signal-to-noise ratio at the output of the third adder 57, since one of the envelope detectors, for example, 55, turns out to be a “locked” signal from the other envelope detector 56.

Video signal

u _n (t) = U _n Cosφ _k (t), 0≤t≤T _c

proportional to the modulating code M (t), from the output of the third adder 57 is fixed by the registration unit 45.

The carrier frequency ω _s and the modulating code M (t) are identification signs of the fire safety object, a fire has occurred. Based on these signs, a control point decides on the place of the fire and measures to eliminate it.

The delay time τ _{1 of} the delay line 41 is selected so that it is possible to fix and analyze the low-frequency voltage u _n (t). A 15-second pulse (t ₁ ≤15 s) is sufficient for reliable alarm transmission. During a period of time t ₂ , the actuator 6 fire extinguishing aerosol generator is connected and started. The specified connection is provided by a time relay 4, by the command of which, at the end of the time period t ₁ , the normally open output contact of the time relay 4 is closed with an electric trigger, for example a generator squib extinguishing aerosol. After triggering the squib of the fire extinguishing aerosol generator, the latter operates autonomously and does not need power supply from current source 2. For a reliable start of the fire extinguishing aerosol generator of the actuator 6, a 5-second pulse is sufficient (t ₂ = 2-5 s).

After the time τ _{1, the} voltage from the output of the threshold block 40 through the delay line 41 is supplied to the reset input of the threshold block 40 and resets its contents to zero. In this case, the key 42 is closed, and the sawtooth voltage generator is turned on, i.e. they are transferred to their original state.

When the next QPSK signal is detected at a different carrier frequency and with a different modeling code, the receiver operates in a similar way.

These signals have high noise immunity, energy and structural secrecy.

The energy secrecy of complex QPSK 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 QPSK signal at the receiving point may be masked by noise and interference. Moreover, the energy of a complex QPSK signal is by no means small; it is simply distributed over the time-frequency domain so that at each point of this region the signal power is less than the power of noise and interference.

The structural secrecy of complex QPSK signals is due to the wide variety of their shapes and significant ranges of parameter changes, which makes it difficult to optimize or at least quasi-optimal processing of QPSK signals of an a priori unknown structure in order to increase the sensitivity of the receiver.

The operation of the receiver described above corresponds to the case of receiving useful PSK signals along the main channel at a frequency of ω _s (Fig. 7).

If a false signal (interference) is received on the first mirror channel at a frequency ω _s1

_Z1 u (t) = U _P1 · Cos (ω t + φ _{P1 P1),} 0≤t≤T _P1,

then at the output of the mixers 31 and 47 the following voltages are generated, respectively:

u _up5 (t) = U _pr5 Cos (ω _up t-πγt ² + φ _up5 ),

u _up6 (t) = U _pr6 · Cos (3ω _up t + πγt ² + φ _up6), 0≤t≤T _P1,

;Where

;

;

;

ω _up = ω _r1 -ω _z1 - intermediate frequency;

3ω _up = ω _r2 -ω _z1 is the triple value of the intermediate frequency;

φ _up5 = φ _r1 -φ _P1, φ _up6 = φ _r2 -φ _P1.

However, only the voltage u _up5 (t) falls into the passband of the first intermediate frequency amplifier 34 and to the first input of the correlator 49. The output voltage of the correlator 49 is zero, the key 51 does not open, and a false signal (interference) received via the first mirror channel at the frequency ω _s1 is suppressed.

If a false signal (interference) is received on the second mirror channel at a frequency ω _z2

u _z2 (t) = U _z2 · Cos (ω _z2 t + φ _z2 ), 0≤t≤T _z ,

then at the output of the mixers 31 and 47 the following voltages are generated, respectively:

u _up7 (t) = U _pr7 Cos (3ω _up t-πγt ² + φ _up7 ),

u _up8 (t) = U _pr8 · Cos (3ω _up t-πγt ² + φ _up8), 0≤t≤T _s2

;

;

;

;

3ω _up = ω _З2 -ω _r1 is the triple value of the intermediate frequency;

φ _up = ω _З2 -ω _r2 - intermediate frequency;

φ _up7 = φ _z2 -φ _r1 , φ _up8 = φ _z2 -φ _r2 .

However, only the voltage u _up8 (t) falls into the passband of the second intermediate-frequency amplifier 48 and to the second input of the correlator 49. The output voltage of the correlator 49 is also zero, the key 51 does not open, and a false signal (interference) received via the first mirror channel at the frequency ω _z2 is suppressed.

For a similar reason, false (interference) received on the first Raman channel at a frequency ω _k1 , or on a second Raman channel at a frequency ω _k2 , or through any other Raman channel, is also suppressed.

If false signals (interference) are simultaneously received through the first ω _z1 and second ω _z2 mirror channels, then voltages are generated at the output of the mixers 34 and 47:

u _up5 (t) = U _pr5 Cos (ω _up t-πγt ² + φ _up5 ),

u _up8 (t) = U _pr8 Cos (ω _up t-πγt ² + φ _up8 ),

which fall into the passband of the amplifiers 34 and 48 of the intermediate frequency, respectively, and the two inputs of the correlator 49. But the key 51 in this case does not open. This is due to the fact that two false signal u _P1 (t) and u _s2 (t) takes on different frequencies ω _P1 and ω _P2, between the educated channel voltages u _UP5 (t) and u _UP8 (t) there is a weak correlation between the output the voltage of the correlator 49 does not reach the maximum value and does not exceed the threshold level U _pore1 in the threshold block 50. The key 51 does not open and false signals (interference) received simultaneously on the first ω _z1 and ω _z2 mirror channels are suppressed.

For a similar reason, false signals (interference) are simultaneously suppressed via the first ω _k1 and second ω _k2 combinational or two other combinational channels.

The proposed system provides increased noise immunity and selectivity of the receiver. This is achieved by suppressing false signals (interference) received via mirror and Raman channels due to the correlation processing of channel voltages. The remarkable property of the correlation function of complex signals with phase shift keying is used.

Thus, the proposed system, in comparison with the prototype and other technical solutions of a similar purpose, provides increased noise immunity and reliability of the transmission of alarms from the container base bearing structure to the control point, remote at a considerable distance. This is achieved through the use of repeaters located on the spacecraft of the satellite communication system, and by increasing the dynamic range of the input signals and the signal-to-noise ratio of the receiver of the control point.

Adders made, for example, on resistors are practically inertialess, the time constant of the envelope detectors can be made very small. In addition, the absence of combinational components of higher orders, which are formed during multiplication in the phase detector, can improve the technical characteristics of the proposed system.

Claims (1)

A fire protection system for a container base supporting structure, comprising an autonomous fire alarm system placed on a container base bearing, a receiver located at the control point, and a radio channel installed between them and operating in simplex mode, while an autonomous fire alarm system contains a registration unit and a series-connected thermal actuator, a current source with a pyrotechnic activator and a time relay that is connected to the signal the device through a normally closed contact and is additionally connected to the actuator through a normally open contact, while the thermal starter and the current source with the pyrotechnic activator are structurally combined and enclosed in a housing, the thermal starter is made in the form of a spring-loaded rod installed with the possibility of translational movement and interaction with pyrotechnic activator of the current source, and one of the end sections of the spring-loaded rod is located from the housing and is equipped with a latch made of a material with a thermochemical shape memory, the current source includes a shell with a solid state block placed in it with the possibility of contact with a pyrotechnic activator made of a solid salt, non-detachable electrochemical composition based on lithium alloy and iron disulfide, the signal device is made in the form of a signal transmitter to a remote receiver, while the signal transmitter is made in the form of serially connected master oscillator, n-tap delay line, phase the rotors included in the m-taps of the n-tap delay line, the adder, the (n + 1) -th input of which is connected to the output of the master oscillator, power amplifier and transmitting antenna, and the receiver is made in the form of series-connected receiving antenna, high-frequency amplifier, the first mixer, the second input of which is connected through the first local oscillator to the output of the sawtooth generator, the first intermediate frequency amplifier, the correlator, the second threshold block, the second key, the second input of which is connected to the output of the first amplifier intermediate frequency, phase doubler, second spectrum analyzer, comparison unit, the second input of which through the first spectrum analyzer is connected to the output of the second key, the first threshold block, the second input of which is connected to its output through the first delay line, the first key, the second input of which is connected to the output of the second key, and the second delay line, connected in series to the output of the sawtooth voltage generator of the second local oscillator, the second mixer, the second input of which is connected to the output of the high hour amplifier Ota, and the second intermediate frequency amplifier, whose output is connected to a second input of the correlator, the control input of the sawtooth generator is connected to the output of the first threshold block frequency ω _r1 and ω _r2 of the first and second local oscillators are separated by twice the value of the intermediate frequency
ω _r2 -ω _r1 = 2ω _up ,
selected symmetrical with respect to the carrier frequency ω _{from the} received signal
ω _c -ω _r1 = ω _r2 -ω _c = ω _up
and are tuned synchronously, characterized in that it is equipped with repeaters located on the spacecraft of the satellite communication system, the receiver located at the control point is equipped with a phase inverter, three adders and two envelope detectors, and the first adder, the second input, are connected in series to the output of the second delay line which is connected to the output of the first key, the first envelope detector and the third adder, the output of which is connected to the input of the registration unit, to the output of the second delay line a phase inverter are connected, a second adder, a second input coupled to an output of the first switch and a second envelope detector, whose output is connected to a second input of the third adder.

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