RU2452985C2 - Automated system for emergency and environmental monitoring of region - Google Patents

Abstract

FIELD: physics.

SUBSTANCE: system has stationary and mobile monitor stations, direct and feedback links and a central control station. Each of the stationary and mobile stations includes an information pre-processing unit, an encryption unit, a noiseless coding unit, an analogue message unit, a receiver, a control unit and direct and feedback channels. Each mobile station further includes a position finding unit. Each transceiver has a driving generator (20), a phase-shift keying device (21), an amplitude modulator (22), first and second heterodynes (23, 30), first, second and third mixers (24, 31, 57), a first intermediate frequency amplifier (25), first and second power amplifiers (26, 29), a duplexer (27), a transmit/receive antenna (28), first and second second-intermediate frequency amplifiers (32, 58), an amplitude limiter (33), a synchronous detector (34), first and second multipliers (35, 61), a band-pass filter (36), a phase detector (37), a -90° phase changer (56), a +90° phase changer (59), an adder (69), a narrow-band filter (62), an amplitude detector (63) and a switch (64).

EFFECT: high reliability of monitoring results.

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Description

The proposed system relates to the field of control and measuring systems and can be used in the design of emergency and environmental monitoring systems of the environment of the region.

The systems of emergency and ecological monitoring of the environment of the region are known (RF patents Nos. 2.079.891, 2.138.126, 2.145.120, 2.150.126, 2.210.095, 2.257.598, 2.310.895; US patent No. 3,819.862; Micah E. et al. “The System of Radiation Monitoring of the Environment”, Journal of Atomic Engineering Abroad, M., 1998, No. 11, pp. 21-25 and others).

Of the known systems, the closest to the proposed is the "Automated system for emergency and ecological monitoring of the environment of the region" (RF patent No. 2.310.895, G01W 1/06, 2006), which is selected as a prototype.

The specified system provides the exchange of discrete and analog information between control posts and a control center.

However, in transceivers located at control posts, the same value of the second intermediate frequency ω _{pr2 is} formed when signals are received at two frequencies: ω ₁ and ω _s1 , i.e.

_np2 ω = ω ₁ -ω _r1 and _np2 ω = ω -ω _{r1 P1,}

and in the transceiver located at the control room, the same value of the second intermediate frequency ω _{pr2 is} formed when signals are received at two frequencies: ω ₂ and ω _z2 , i.e.

_np2 ω = ω _z2 -ω and ω ₂ = ω _{s2 np2 z2} -ω,

where ω _g1 and ω _g2 are the frequencies of the local oscillators,

spaced by the value of the second intermediate frequency:

w _{r1 r2} -ω = ω _WP2.

Therefore, if the tuning frequencies ω ₁ and ω _{2 are} taken as the main receiving channels, then along with them there will be mirror receiving channels, the frequencies ω _s1 and ω _{z2 of} which are separated from the frequencies ω ₁ and ω _{2 of the} main receiving channels by twice the value of the second intermediate frequency 2ω _pr2 and are located symmetrically (mirror) relative to the frequencies ω _g1 and ω _g2 local oscillators (Fig.6).

The conversion through the mirror channels of reception occurs with the same conversion coefficient Kpr as the main channels of reception, so they most significantly affect the noise immunity and selectivity of the receivers.

In addition to mirrored, there are other additional (combination) reception channels. In general terms, any combination receive channel takes place when the following conditions are met:

ω _pr2 = | ± m * ω _ki ± n * ω _g |,

where ω _ki is the frequency of the i-th Raman reception channel;

m, n, i are positive integers.

The most harmful combinational reception channels are those that form when the first harmonic of the signal frequency interacts with the harmonics of the frequencies of small order oscillators (second, third), since the sensitivity of the receiver through these channels is close to the sensitivity of the main channel. So, four combination channels with m = 1 and n = 2 correspond to frequencies:

ω _k1 = 2ω _{g1 -ω pr2} ,

ω _k2 = 2ω _g1 + ω _pr2 ,

ω _k3 = 2ω _r2 -ω _WP2,

ω _k4 = 2ω + ω _{r2 WP2.}

The presence of false signals (interference) received via mirror and Raman channels leads to a decrease in the selectivity and noise immunity of receivers installed at control posts and control room.

An object of the invention is to increase the selectivity and noise immunity of receivers located at control posts and a control room by suppressing false signals (interference) received via mirror and Raman channels.

The problem is solved in that an automated system for emergency and ecological monitoring of the environment of the region, including, in accordance with the closest analogue, stationary control posts with detectors for measuring environmental parameters and characteristics, mobile control posts with detectors, each of which includes a location unit , central control point, control units and transceivers of direct and feedback control posts with a central control point, pr and each of the stationary and mobile control posts additionally contains an information pre-processing unit, to which data of measurements of parameters and environmental characteristics are transmitted from the sensors of stationary and mobile control posts, and information from the preliminary processing unit enters the control unit of the corresponding control post, then encryption block from unauthorized access and then through the noise-resistant coding block to the transceiver, the information from which is received to the central control point, each transceiver is made in the form of a serially connected master oscillator, a phase manipulator, the second input of which is connected to the output of the noise-resistant coding unit, an amplitude modulator, the second input of which is connected to the output of the analog message block, the first mixer, the second input of which is connected to the output the first local oscillator, the amplifier of the first intermediate frequency, the first power amplifier, the duplexer, the input-output of which is connected to the transceiver antenna, a second power amplifier, a second mixer, the second input of which is connected to the output of the second local oscillator, and a second intermediate frequency amplifier, a series-connected amplitude limiter and a synchronous detector, the output of which is the first output of the transceiver, connected in series to the output of the first local oscillator of the first multiplier, the second input of which is connected with an output of an amplitude limiter, a band-pass filter, and a phase detector, the second input of which is connected to the output of the second local oscillator, and the output a second output of transceiver frequency oscillators spaced apart by the value of the second intermediate frequency

w _{r1 r2} -ω = ω _WP2,

each of the stationary and mobile control posts emits complex signals with combined phase shift keying and amplitude modulation on one carrier frequency

ω = ω ₁ = ω _{z2 pr1,}

but takes on a different frequency

ω ₂ = ω _CR = ω _g1 ,

where ω _CR - the intermediate frequency;

ω _CR1 - the first intermediate frequency;

ω _g1 , ω _g2 are the frequencies of the first and second local oscillators,

and the central control point, on the contrary, emits complex signals with combined phase shift keying and amplitude modulation at one carrier frequency ω ₂ , and receives at another frequency ω ₁ , differs from the closest analogue in that each transceiver is equipped with two phase shifters of + 90 ° and - 90 °, a third mixer, a second amplifier of a second intermediate frequency, an adder, a second multiplier, a narrow-band filter, an amplitude detector and a key, with the first connected to the second output of the second local oscillator the first phase shifter -90 °, the third mixer, the second input of which is connected to the output of the second power amplifier, the second amplifier of the second intermediate frequency, the second phase shifter of + 90 °, the adder, the second input of which is connected to the output of the first amplifier of the second intermediate frequency, the second multiplier, the second input of which is connected to the output of the second power amplifier, a narrow-band filter, an amplitude detector and a key, the second input of which is connected to the output of the adder, and the output is connected to the input of the amplitude limiter and to the second input dy synchronous detector to the second output of the second heterodyne transceiver checkpoint each phase shifter is connected to -90 °.

The structural diagram of the system is presented in figure 1. The structural diagram of a stationary control post is depicted in figure 2. The structural diagram of the mobile control post is shown in Fig.3. The structural diagram of the transceiver located at each stationary and mobile control post is depicted in figure 4. The structural diagram of the transceiver located at the Central control point, shown in Fig.5. A frequency diagram explaining the process of converting signals by frequency is shown in FIG. 6. Timing diagrams explaining the principle of operation of the transceiver are shown in Fig.7.

The system contains stationary control posts 1 (C ₁ , ..., C _n ), mobile control posts 2 (M ₁ , ..., M _m ), direct and feedback 3, Central control point 4.

Each stationary control station contains detectors D ₁ ÷ D _k , preprocessing unit 5.i, encryption unit 6.i, error-correcting encoding unit 7.i, analog message unit 8.i, transceiver 9.i, control unit 10.i, channel 11.i direct and feedback (i = 1, 2, ..., n).

Each mobile control post contains detectors D ₁ ÷ D _L , information preprocessing unit 12.j, encryption unit 13.j, error-correcting encoding unit 14.j, analog message unit 15.j, transceiver 16.j, control unit 17.j , direct and feedback channel 18.j, position determining block 19.j (j = 1, 2, ..., m).

Each transceiver is made in the form of series-connected master oscillator 20 (38), phase manipulator 21 (39), the second input of which is connected to the output of the noise-resistant coding unit 7 (14), amplitude modulator 22 (40), the second input of which is connected to the output of block 8 (15) analog messages, the first mixer 24 (42), the second input of which is connected to the output of the first local oscillator 23 (41), the amplifier 25 (43) of the first intermediate frequency, the first power amplifier 26 (44), the duplexer 27 (45), the input - the output of which is associated with the transceiver antennas th 28 (46), the second power amplifier 29 (47), the second mixer 31 (49), the second input of which is connected to the first output of the second local oscillator 30 (48), the first amplifier 32 (50) of the second intermediate frequency, adder 60 (69) , a second multiplier 61 (70), the second input of which is connected to the output of the second power amplifier 29 (47), a narrow-band filter 62 (71), an amplitude detector 63 (72), a key 64 (73), the second input of which is connected to the output of the adder 60 (69), an amplitude limiter 33 (51) and a synchronous detector 34 (52), the second input of which is connected to the output of the key 64 (73), and the output One is the first I output of the transceiver 9 (16), connected in series to the output of the first local oscillator 23 (41) of the first multiplier 35, the second input of which is connected to the output of the amplitude limiter 33 (51), the bandpass filter 36 (54) and the phase detector 37 (55 ), the second input of which is connected to the output of the second local oscillator 30 (48), and the output is the second II output of the transceiver 9 (16), connected in series to the second output of the second local oscillator 30 (48) of the first phase shifter 56 (65), third mixer 57 (66) ), the second input of which is connected to the output the house of the second power amplifier 29 (47), the second amplifier 58 (67) of the second intermediate frequency and the second phase shifter 59 (68) + 90 °, the output of which is connected to the second input of the adder 60 (69).

The system operates as follows.

Each stationary and mobile control post consists of detectors D ₁ ÷ D _k , D ₁ ÷ D _L measuring the state of the environment (gamma radiation level, temperature, etc.), from the outputs of which data are fed to the inputs of blocks 5.1 and 12. j (i = 1, 2, ..., n, j = 1, 2, ..., m) of preliminary information processing, respectively, about this state of the medium. In these blocks, according to the program recorded in the control blocks 10.j and 17.j, the integral parameters of the medium are determined (average values for a given period of measurements, trend, etc.), the amount of information transmitted to the communication channel is reduced, and the pre-emergency or emergency situation is determined , accumulation and storage of data from previous measurements, etc. For example, a gamma-ray spectrometric detector measures the number and energy of gamma rays that have fallen into its sensor during the measurement, for example, in 1 hour. These data from the output of the detectors are fed to the input of the preliminary information processing blocks 5.i and 12.j, where the obtained energy “spectrum” of the distribution determines, for example, the excess of the radiation level of various radionuclides in the medium over a threshold level, for example, an emergency level.

If such an excess of the level has occurred, then the control units 10.i and 17.j according to the internal program go into pre-emergency or emergency operation, make emergency contact with the central control point 4 and (if necessary) notify the personnel. If the communication channel is busy or faulty, then information is stored in the storage device and re-contacted.

The pre-processed - compressed (due to the reduction of redundancy or low information content) information is transmitted to the communication channels 11.i and 18.j. For example, you can significantly reduce the amount of information transmitted over the communication channel using the fast Fourier transform of the resulting spectrum. Accordingly, almost the same number of times it becomes possible to increase the number of control posts working in this channel. In a number of cases, it is sufficient to transmit integral (averaged over many measurements) values of the monitored environmental parameter, for example, the background radiation level or exceeding the emergency level threshold. The performance of this function by blocks 5.i and 12.j of preliminary processing of information also leads to a significant reduction in the amount of information transmitted. The outputs of these blocks are connected to the inputs of the encryption blocks 6.i and 13.j, providing, for example, cryptographic encryption of information from unauthorized access. In this case, the system is protected from terrorists, hackers or anyone who does not have the right to receive, convert or enter distorted information if the secret keys have not been compromised.

The outputs of the encryption blocks 6.i and 13.j are connected to the inputs of the error-correcting coding blocks 7.i and 14.j, which ensure the detection and correction of reception errors in the central control point 4. Errors can occur due to interference and noise in the communication channel and / or in receiving equipment. The outputs of the error-correcting coding blocks 7.i and 14.j through the analog message blocks 8.i and 15.j are connected to the inputs of the transceivers 9.i and 16.j, the outputs of which are connected to the inputs of the communication channels 11.i and 18.j, respectively. The control inputs of all these blocks are connected to the outputs of the control blocks 10.i and 17.j, which determine the mode of their operation according to internal programs or commands transmitted from the central control point (dispatch center) 4.

When you turn on the master oscillator 20, the latter generates harmonic oscillation (Fig.7, a)

U _c1 (t) = υ _c1 * Cos (ω _c t + φ _c1 ), 0≤t≤T _c1 ,

where υ _c1 , ω _c , φ _c1 , T _c1 is the amplitude, carrier frequency, initial phase and duration of the oscillation, which is supplied to the first input of the phase manipulator 21, the second input of which is supplied with the modulating code M ₁ (t) (Fig. 7, b) from the output of block 7 noise-resistant coding. At the output of the phase manipulator 21, a complex signal with phase shift keying (QPSK) is generated (Fig. 7, c)

U _{1 (t) = υ c1 * Cos} [ω c t + φ k1 (t) + φ _c1], 0≤t≤T _c1,

where φ _k1 (t) = {0, π} is the manipulated phase component that displays the phase manipulation law in accordance with the modulating code M ₁ (t) (Fig. 7, b), while φ _k1 (t) = const for k * τ _e <t <(k + 1) * τ _e and can change stepwise at t = k * τ _e , i.e. at the borders between elementary premises (k = 1, 2, ..., N-1);

τ _e , N is the duration and number of chips that make up the signal of duration T _c1 , (T _c1 = N * τ _e ),

which is fed to the first input of the amplitude modulator 22. The modulating function m ₁ (t) (Fig. 7, d) from the output of the analogue message block 8 is received at the second input of the amplitude modulator 22. At the output of the amplitude modulator 22, a complex signal is generated with combined phase shift keying and amplitude modulation (QPSK-AM) at one carrier frequency (Fig. 7, d)

U ₂ (t) = υ _c1 [1 + m ₁ (t)] * Cos [ω c t + φ k1 (t) + φ _c1], 0≤t≤T _c1,

where m ₁ (t) is the modulating function that displays the law of amplitude modulation.

The generated signal U ₂ (t) is fed to the first input of the first mixer 24, the second input of which is supplied with the voltage of the first local oscillator 23

U _g1 (t) = υ _g1 * Cos (ω _g1 t + φ _g1 ).

At the output of the mixer 24, voltages of combination frequencies are generated. The amplifier 25 is allocated the voltage of the first intermediate (total) frequency (Fig.7, e)

U _pr1 (t) = υ _pr1 [1 + m ₁ (t)] * Cos [ω _pr1 t + φ _k1 (t) + φ _pr1 ], 0≤t≤T _c1 ,

where υ _pr1 = 1/2 * υ _c1 * υ _g1 ;

ω _pr1 = ω _s1 + ω _g1 - the first intermediate frequency (Fig.6);

φ _pr1 = φ _c1 + φ _g1 .

This voltage, after amplification in the power amplifier 25, enters through the duplexer 27 to the transceiver antenna 28, is radiated by it at a frequency ω ₁ = ω _pr1 , is picked up by the transceiver antenna 46 of the central control point (control center), and through the power amplifier 47 is supplied to the first inputs of the mixers 49 and 66, to the second inputs of which the voltage of the local oscillator 48 is supplied.

U _g1 (t) = υ _g1 * Cos (ω _g1 t + φ _g1 ),

U _g1 ′ (t) = υ _g1 * Cos (ω _g1 t + φ _g1 + 90 °).

At the output of the mixers 49 and 66, voltages of combination frequencies are generated. Amplifiers 50 and 67 are allocated voltage of the second intermediate (differential) frequency

U _CR2 (t) = υ _CR2 [1 + m ₁ (t)] * Cos [ω _CR2 t + φ _k1 (t) + φ _CR2 ],

U _CR3 (t) = υ _CR2 [1 + m ₁ (t)] * Cos [ω _CR2 t + φ _k1 (t) + φ _CR2 -90 °], 0≤t≤T _c1 ,

where υ _pr2 = l / 2 * υ _pr1 * υ _g1 ;

ω _CR2 = ω _CR1- ω _g1 - the second intermediate frequency;

φ _pr2 = φ _pr1 -φ _g1 .

The voltage U _pr3 (t) from the output of the amplifier 67 of the second intermediate frequency is supplied to the input of the phase shifter 68 by 90 °, at the output of which a voltage is generated

U _CR4 (t) = υ _CR2 [1 + m ₁ (t)] * Cos [ω _CR2 t + φ _k1 (t) + φ _CR2 -90 ° + 90 °] =

= υ _CR2 [1 + m ₁ (t)] * Cos [ω _CR2 t + φ _k1 (t) + φ _CR2 ], 0≤t≤T _c1 .

Voltages U _CR2 (t) and U _CR4 (t) are supplied to two inputs of the adder 69, the output of which is formed by the total voltage (Fig.7, g)

U _Σ1 (t) = υ _Σ1 [1 + m ₁ (t)] * Cos [ω _pr2 t + φ _k1 (t) + φ _pr2 ], 0≤t≤T _c1 ,

where υ _Σ1 = 2υ _pr2 ,

which is fed to the second input of the multiplier 70. At the first input of the last receives the received PSK signal U _pr1 (t) from the output of the power amplifier 47. At the output of the multiplier 70, a voltage is generated (Fig. 7, h)

U ₃ (t) = υ ₃ [1 + m ₁ (t)] ² * Cos (ω _g1 t + φ _g1 ), 0≤t≤T _C1 ,

where υ ₃ = 1/2 * υ _pr1 * υ _Σ1 ,

which is allocated by a narrow-band filter 71, the tuning frequency ω _{n1 of} which is chosen equal to the frequency ω _{g1 of the} local oscillator 48 (ω _n1 = ω _g1 ), is detected by the amplitude detector 72 and fed to the control input of the key 73, opening it. In the initial state, keys 64 and 73 are always closed.

In this case, the total voltage U _Σ1 (t) from the output of the adder 69 through the public key 73 is fed to the first (information) input of the synchronous detector 52 and to the input of the amplitude limiter 51. The voltage is generated at the output of the latter

U ₄ (t) = υ ₀ * Cos [ω _CR2 t + φ _k1 (t) + φ _CR2 ], 0≤t≤T _C1 ,

where υ ₀ is the limit threshold,

which is a complex signal with phase shift keying at the second intermediate frequency, is used as a reference voltage and is supplied to the second (reference) input of the synchronous detector 52. As a result of synchronous detection, a low-frequency voltage is generated at the output of the synchronous detector 52 (Fig. 7, and)

U _H1 (t) = υ _H1 [1 + m ₁ (t)], 0≤t≤T _C1 ,

where υ _Н1 = 1/2 * υ _Σ1 * υ ₀ ,

proportional to the modulating function m ₁ (t) (Fig.7, g). This voltage from the first I output of the transceiver 16 is supplied to the recording and analysis unit.

The voltage U ₄ (t) from the output of the amplitude limiter 51 is supplied to the first input of the multiplier 53, the second input of which is the voltage of the local oscillator 41

U _g2 (t) = υ _g2 * Cos (ω _g2 t + φ _g2 ).

The output of the multiplier 53 produces a voltage (Fig.7, k)

U ₅ (t) = υ ₅ * Cos [ω _g1 t-φ _k1 (t) + φ _g1 ], 0≤t≤T _C1 ,

where υ ₅ = 1/2 * υ ₀ * υ _g2 ,

which is allocated by a band-pass filter 54 and fed to the first (information) input of the phase detector 55. The voltage U _g1 (t) of the local oscillator 48 is applied to the second (reference) input of the phase detector 55. As a result of phase detection, a low-frequency voltage is generated at the output of the phase detector 55 (Fig. .7, l)

U _H2 (t) = υ _H2 * Cosφ _k1 (t), 0≤t≤T _C1 ,

where U _H2 = 1/2 * υ ₅ * υ _g1 ,

proportional to the modulating code M ₁ (t) (Fig.7, b). This voltage from the second II output of the transceiver 16 is supplied to the recording and analysis unit.

At the central control point (control center) using the master oscillator 38, a harmonic oscillation is generated

_{U c2 (t) = υ c2} * Cos (ω c t + φ _c2), 0≤t≤T _C2,

which is supplied to the first input of the phase manipulator 39, to the second input of which a modulating code M ₂ (t) is supplied from the output of the noise-resistant coding unit 14. The modulating code M ₂ (t) may contain request signals, commands to turn control posts on and off, etc. At the output of the phase manipulator 39, a complex QPSK signal is formed

U ₆ (t) = υ _c2 * Cos [ω _c t + φ _k2 (t) + φ _c2 ], 0≤t≤T _C2 ,

which is fed to the first input of the amplitude modulator 40. The modulating function m ₂ (t) is supplied to the second input of the amplitude modulator 40 from the output of the block 15 of analog messages. At the output of the amplitude modulator 40, a complex signal is generated with combined phase shift keying and amplitude modulation (QPSK-AM) at one carrier frequency

₇ U (t) = υ _c2 [1 + m ₂ (t)] * Cos [ω c t + φ k2 (t) + φ _s2], 0≤t≤T _C2.

The generated signal U ₇ (t) is supplied to the first input of the mixer 42, the second input of which is supplied with the voltage U _g2 (t) of the local oscillator 41. At the output of the mixer 42, voltage of combination frequencies is generated. The amplifier 43 allocates an intermediate frequency voltage

U _pr5 (t) = υ _pr5 [1 + m ₂ (t)] * Cos [ω _pr t-φ _k2 (t) + φ _pr5 ], 0≤t≤T _C2 ,

where υ _pr5 = 1/2 * υ _c2 * υ _g2 ;

ω _CR = ω _g2 -ω _c is the intermediate frequency;

_np5 cp = φ -φ _{r2 s2.}

This voltage after amplification in the power amplifier 44 through the duplexer 45 enters the transceiver antenna 46, is radiated by it at a frequency ω ₂ = ω _pr , is captured by the transceiver antenna 28 and through the duplexer 27 and the power amplifier 29 is fed to the first inputs of the mixers 31 and 57, the second inputs of which the voltage of the local oscillator 30 is applied:

U _g2 (t) = υ _g2 * Cos (ω _g2 t + φ _g2 ),

U _g2 ′ (t) = υ _g2 * Cos (ω _g2 t + φ _g2 -90 °).

At the output of the mixers 31 and 57, voltages of combination frequencies are generated. Amplifiers 32 and 58 are allocated voltage of the second intermediate (differential) frequency

U _CR6 (t) = υ _CR6 [1 + m ₂ (t)] * Cos [ω _CR2 t + φ _k2 (t) + φ _CR6 ],

U _pr7 (t) = υ _pr6 [1 + m ₂ (t)] * Cos [ω _pr2 t + φ _k2 (t) + φ _pr6 -90 °], 0≤t≤T _C2 ,

_pr6 where υ = 1/2 * υ * υ _{np2, r2;}

_np2 ω = ω _z2 -ω _etc. - intermediate frequency;

φ _pr6 = φ _r2 -φ _pr5.

The voltage U _pr7 (t) from the output of the amplifier 58 of the second intermediate frequency is supplied to the input of the phase shifter 59 by + 90 °, at the output of which a voltage is generated

U _pr8 (t) = υ _pr6 [1 + m ₂ (t)] * Cos [ω _pr2 t + φ _k2 (t) + φ _pr6 -90 ° + 90 °] =

= υ _CR6 [1 + m ₂ (t)] * Cos [ω _CR2 t + φ _k2 (t) + φ _CR6 ], 0≤t≤T _C2 .

Voltages U ₆ (t) and U _CR8 (t) are fed to two inputs of the adder 60, the output of which is formed by the total voltage

U _Σ2 (t) = υ _Σ2 [1 + m ₂ (t)] * Cos [ω _pr2 t + φ _k2 (t) + φ _pr6 ], 0≤t≤T _C2 ,

where υ _Σ2 = 2υ _pr6 ,

which is fed to the second input of the multiplier 61. The received _QPSK signal U _pr5 (t) from the output of the power amplifier 29 is received at the first input of the last. At the output of the multiplier 61, a voltage is generated

₈ U (t) = υ ₈ [1 + m ₂ (t)] * Cos (ω t + φ _{r2 r2)} 0≤t≤T _C2

where υ ₈ = 1/2 * υ _pr5 * υ _Σ2 ,

is allocated narrowband filter 62, the tuning frequency ω _2n is chosen equal to the frequency ω LO 30 _r2 (ω _2n = ω _z2) is detected by an amplitude detector 63 and applied to the control input of the switch 64, opening it.

In this case, the total voltage U _Σ2 (t) from the output of the adder 60 through the public key 64 is supplied to the first (information) input of the synchronous detector 34 and to the input of the amplitude limiter 33. The voltage is generated at the output of the latter

U ₉ (t) = υ ₀ * Cos [ω _CR2 t + φ _k2 (t) + φ _CR6 ], 0≤t≤T _C2 ,

where υ ₀ is the limit threshold,

which is a complex signal with phase shift keying at the second intermediate frequency, is used as a reference voltage and is fed to the second (reference) input of the synchronous detector 34. As a result of the synchronous detector 34, a low-frequency voltage is generated

U _n3 (t) = υ _n3 [1 + m ₂ (t)], 0≤t≤T _C2 ,

where υ _н3 = 1/2 * υ _Σ2 * υ ₀ ,

proportional to the modulating function m ₂ (t). This voltage from the first I output of the transceiver 9 enters the registration and analysis unit.

The voltage U ₉ (t) from the output of the amplitude limiter 33 is supplied to the first input of the multiplier 35, the second input of which is supplied with the voltage U _g1 (t) of the local oscillator 23. A voltage is generated at the output of the multiplier 35

₁₀ U (t) = υ ₁₀ * Cos [ω _{z2 t-φ k2 (t) +} φ _r2] 0≤t≤T _C2

where υ ₁₀ = 1/2 * υ ₀ * υ _g1 ,

which is allocated by a band-pass filter 36 and supplied to the first (information) input of the phase detector 37. The second (reference) input of the latter is supplied with the voltage U _g2 (t) of the local oscillator 30. A low-frequency voltage is generated at the output of the phase detector 37

U _n4 (t) = υ _n4 * _{Cosφ k2} (t), 0≤t≤T _C2 ,

where υ _н4 = 1/2 * υ ₁₀ * υ _g2 ,

proportional to the modulating code M ₂ (t). This voltage from the second II output of the transceiver 9 enters the registration and analysis unit.

In this case, the frequencies ω _g1 and ω _{g2 of the} local oscillators 23 (48) and 30 (41) are spaced apart by a second intermediate frequency

w _{r1 r2} -ω = ω _WP2.

Each stationary and mobile control post emits complex signals with combined phase shift keying and amplitude modulation (FMN-AM) at a frequency

ω ₁ = ω _CR 1 = ω ₂ ,

but takes on the frequency

ω ₂ = ω _ol = ω _g1 .

The central control point (control center), on the contrary, emits complex signals with combined phase shift keying and amplitude modulation (FMN-AM) at a frequency of ω ₂ , and receives at a frequency of ω ₁ .

The specified system provides increased noise immunity and reliability of the exchange of confidential information between control posts and a control center. This is achieved by using two frequencies ω ₁ , ω ₂ and complex signals with combined phase shift keying and amplitude modulation (PSK-AM). At the same time, the protection of confidential information has three levels: cryptographic, energy, and structural.

The cryptographic level is provided by special methods of encrypting, encoding and converting confidential information, as a result of which its content becomes inaccessible without presenting the cryptogram key and reverse transformation.

The energy and structural levels are provided by the use of complex signals with combined phase shift keying and amplitude modulation (FMN-AM), which have high energy and structural secrecy.

The energy secrecy of these signals is due to their high compressibility in time or in the spectrum with optimal processing, which reduces the instantaneous radiated power. As a result, the complex signal used 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 evenly 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 QPSK-AM signals is caused by a wide variety of their shapes and significant ranges of parameter changes, which makes it difficult to optimize or at least quasi-optimal processing of complex QPSK-AM signals of an a priori unknown structure in order to increase the sensitivity of the receiver.

Complex FMN-AM signals open up new possibilities in the technique of transmitting confidential messages and protecting them from unauthorized access. These signals allow the use of a new type of selection - structural selection. This means that there is a new opportunity to distinguish complex FMN-AM signals from other signals and interference operating in the same frequency band and at the same time intervals. This feature is realized by convolution of the spectrum of complex FMN-AM signals.

The system operation described above corresponds to the case of receiving useful complex signals with combined phase shift keying and amplitude modulation (PSK-AM) through the main channels at frequencies ω ₁ and ω ₂ .

If a false signal (interference) is received on the first mirror channel at a frequency ω _s1 (Fig.6)

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

the amplifiers 50 and 67 of the second intermediate frequency are allocated the following voltages:

U _pr9 (t) = υ _pr9 * Cos (ω _pr2 t + φ _pr9 ),

_Pr10 U (t) = υ _pr9 * Cos (ω t + φ _{np2 pr9} + 90 °), 0≤t≤T _P1,

where υ _pr9 = 1/2 * υ _z1 * υ _g1 ;

_np2 ω = ω -ω _{r1 P1} - second intermediate frequency;

φ _pr9 = φ _g1 -φ _z1 .

The voltage U _pr10 (t) from the output of the amplifier 67 of the second intermediate frequency is supplied to the input of the phase shifter 68 by 90 °, at the output of which a voltage is generated

U _pr11 (t) = υ _pr9 * Cos (ω _pr2 t + φ _pr9 + 90 ° + 90 °) =

= υ _pr9 * Cos (ω t + φ _{np2 pr9),} 0≤t≤T _P1.

Voltages U _CR9 (t) and U _CR11 (t), supplied to the two inputs of the adder 69, are compensated at its output.

Therefore, a false signal (interference) received through the first mirror channel at a frequency of ω _s1 is suppressed with the help of an “outer ring” consisting of a local oscillator 48, mixers 49 and 66, amplifiers 50 and 67 of the second intermediate frequency, phase shifters 65 and 68 to 90 °, adder 69 and implements phase-compensation method.

For a similar reason, the false signal (interference) received on the first combinational channel at a frequency ω _{k1 is also} suppressed (Fig. 6).

If a false signal (interference) is received on the second Raman channel at a frequency ω _k2

U _k2 (t) = υ _k2 * Cos (ω _k2 t + φ _k2 ), 0≤t≤T _k2 ,

the amplifiers 50 and 67 of the second intermediate frequency are allocated the following voltages:

U _pr12 (t) = υ _pr12 * Cos (ω _pr2 t + φ _pr12 ),

U _CR13 (t) = υ _CR12 * Cos (ω _CR2 t + φ _CR12 -90 °), 0≤t≤T _k2 ,

where υ _pr12 = 1/2 * υ _k2 * υ _g1 ;

ω _CR2 = ω _k2 -2ω _g1 - the second intermediate frequency;

φ _pr12 = φ _k2 -φ _g1 .

The voltage U _pr13 (t) from the output of the amplifier 67 of the second intermediate frequency is supplied to the input of the phase shifter 68 by 90 °, at the output of which a voltage is generated

U _pr14 (t) = υ _pr12 * Cos (ω _pr2 t + φ _pr12 -90 ° + 90 °) =

= υ _CR12 * Cos (ω _CR2 t + φ _CR12 ), 0≤t≤T _k2 .

Voltages U _pr12 (t) and U _pr14 (t) are supplied to two inputs of the adder 69, at the output of which the total voltage is formed

U _Σ3 (t) = υ _Σ3 * Cos (ω _CR2 t + φ _CR12 ), 0≤t≤T _k2 ,

where υ _Σ3 = 2υ _pr12 ,

which is supplied to the second input of the multiplier 70. The received false signal (interference) U _k2 (t) from the output of the power amplifier 47 is received at the first input of the last. At the output of the multiplier 70, a voltage is generated

U ₁₁ (t) = υ ₁₁ * Cos (2ω _g1 t + φ _g1 ), 0≤t≤T _k2 ,

where υ ₁₁ = 1/2 * υ _k2 * υ _Σ3 ,

which does not fall into the passband of narrowband 71, the key 73 does not open.

Consequently, a false signal (interference) received via the second combination channel at a frequency υ _k2 is suppressed with the help of an “inner ring” consisting of a multiplier 70, a narrow-band filter 71, an amplitude detector 72, a key 73, and implementing the narrow-band filtering method.

If a false signal (interference) is received on the second mirror channel at a frequency υ _З2 (Fig.6)

U _s2 (t) = υ _s2 * Cos (ω t + φ _{s2 s2)} 0≤t≤T _s2,

the amplifiers 32 and 58 of the second intermediate frequency are allocated the following voltages:

U _pr15 (t) = υ _pr15 * Cos (ω _pr2 t + φ _pr15 ),

_Pr16 U (t) = υ _pr15 * Cos (ω t + φ _{np2 pr15} + 90 °), 0≤t≤T _s2,

where υ _pr15 = 1/2 * υ _z2 * υ _g2 ;

_np2 ω = ω _z2 -ω _r2 - second intermediate frequency;

φ _pr15 = φ _s2 -φ _g2 .

The voltage U _pr16 (t) from the output of the amplifier 58 of the second intermediate frequency is supplied to the input of the phase shifter 59 by 90 °, at the output of which a voltage is generated

U _pr17 (t) = υ _pr15 * Cos (ω _pr2 t + φ _pr15 + 90 ° + 90 °) =

= -υ _pr15 * Cos (ω t + φ _{np2 pr15),} 0≤t≤T _s2.

The voltage U _pr15 (t) and U _pr17 (t) supplied to the two inputs of the adder 60 are compensated at its output.

Therefore, a false signal (interference) received through the second mirror channel at a frequency of ω _s2 is suppressed using an “outer ring” consisting of a local oscillator 30, mixers 31 and 57, a phase shifter 56 by -90 °, a phase shifter 59 by + 90 °, amplifiers 32 and 58 of the second intermediate frequency, the adder 60 and implements phase-compensation method.

For a similar reason, the false signal (interference) received on the fourth Raman channel at a frequency ω _{k4 is also suppressed} (Fig. 6).

If a false signal (interference) is received on the third combinational channel at a frequency ω _k3

U _k3 (t) = υ _k3 * Cos (ω _k3 t + φ _k3 ), 0≤t≤T _k3 ,

the amplifiers 32 and 58 of the second intermediate frequency are allocated the following voltages:

U _pr18 (t) = υ _pr18 * Cos (ω _pr2 t + φ _pr18 ),

U _pr19 (t) = υ _pr18 * Cos (ω _pr2 t + φ _pr18 -90 °), 0≤t≤T _k3 ,

where υ _pr18 = 1/2 * υ _k3 * υ _g2 ;

_np2 = 2ω ω _z2 -ω _k3 - second intermediate frequency;

_AP18 cp = φ _r2 -φ _k3.

The voltage U _pr19 (t) from the output of the amplifier 58 of the second intermediate frequency is supplied to the input of the phase shifter 59 by + 90 °, at the output of which a voltage is generated

U _pr20 (t) = υ _pr18 * Cos (ω _pr2 t + φ _pr18 -90 ° + 90 °) =

= υ _prl8 * Cos (ω _CR2 t + φ _CR18 ), 0≤t≤T _k3 .

Voltages U _pr18 (t) and U _pr20 (t) are supplied to two inputs of the adder 60, the output of which produces a total voltage

U _Σ4 (t) = υ _Σ4 * Cos (ω _CR2 t + φ _CR18 ), 0≤t≤T _k3 ,

where υ _Σ4 = 2υ _pr18 ,

which is fed to the second input of the multiplier 61. The received false signal (interference) U _k3 (t) from the output of the power amplifier 29 is received at the first input of the last. At the output of the multiplier 61, a voltage is generated

₁₂ U (t) = υ ₁₂ * Cos (2ω t + φ _{r2 r2),} 0≤t≤T _k3,

where υ ₁₂ = 1/2 * υ _k3 * υ _Σ4 ,

which does not fall into the passband of the narrow-band filter 62, the key 64 does not open.

Therefore, a false signal (interference) received via the third combination channel at a frequency ω _k3 is suppressed with the help of an “inner ring” consisting of a multiplier 61, a narrow-band filter 62, an amplitude detector 63, a key 64, and implementing the narrow-band filtering method.

Thus, the proposed system in comparison with the prototype and other technical solutions for a similar purpose provides increased selectivity and noise immunity of receivers located at control posts and control room. This is achieved by suppressing false signals (interference) received on the first and second mirror channels, on the first, second, third and fourth combinational channels.

Claims (1)

An automated system for emergency and ecological monitoring of the environment of the region, including stationary control posts with detectors for measuring environmental parameters and characteristics, mobile control posts with detectors, each of which includes a positioning unit, a central control point, control units and transceivers for direct and feedback control posts with a central control point, with each of the stationary and mobile control posts additionally contains a preliminary information processing unit, into which data of measurements of parameters and environmental characteristics are transmitted from sensors of stationary and mobile control posts, and information from the preliminary processing unit is sent to the control unit of the corresponding control post, then to the encryption block from unauthorized access and then through the noise-resistant block encoding to the block of analog messages, and then to the transceiver, the information from which comes to the central control point, each the second transceiver is made in the form of a serially connected master oscillator, a phase manipulator, the second input of which is connected to the output of the noise-resistant coding unit, an amplitude modulator, the second input of which is connected to the output of the analog message block, the first mixer, the second input of which is connected to the output of the first local oscillator, amplifier of the first intermediate frequency, the first power amplifier, duplexer, the input-output of which is connected to the transceiver antenna, the second power amplifier, the second mixes A, the second input of which is connected to the output of the second local oscillator, and the first amplifier of the second intermediate frequency, a series-connected amplitude limiter and a synchronous detector, the output of which is the first output of the transceiver, sequentially connected to the output of the first local oscillator of the first multiplier, the second input of which is connected to the output of the amplitude limiter , a band-pass filter and a phase detector, the second input of which is connected to the output of the second local oscillator, and the output is the second output at the transmitter, the local oscillator frequencies are spaced by the value of the second intermediate frequency
w _{r1 r2} -ω = ω _WP2,
each of the stationary and mobile control posts emits complex signals with combined phase shift keying and amplitude modulation on one carrier frequency
ω = ω ₁ = ω _{z2 pr1,}
but takes on a different frequency
ω ₂ = ω _CR = ω _g1 ,
where ω _CR - the intermediate frequency;
ω _CR1 - the first intermediate frequency;
ω _g1 , ω _g2 are the frequencies of the first and second local oscillators,
and the central control point, on the contrary, emits complex signals with combined phase shift keying and amplitude modulation at one carrier frequency ω ₂ , and receives at another frequency ω ₁ , characterized in that each transceiver is equipped with phase shifters of + 90 ° and -90 °, the third a mixer, a second amplifier of the second intermediate frequency, an adder, a second multiplier, a narrow-band filter, an amplitude detector and a key, and the first phase shifter -90 °, tr the second mixer, the second input of which is connected to the output of the second power amplifier, the second amplifier of the second intermediate frequency, the second phase shifter by + 90 °, the adder, the second input of which is connected to the output of the first amplifier of the second intermediate frequency, the second multiplier, the second input of which is connected to the output of the second a power amplifier, a narrow-band filter, an amplitude detector and a key, the second input of which is connected to the output of the adder, and the output is connected to the input of the amplitude limiter and to the second input of the synchronous detector, -90 ° phase shifter is connected to the second output of the second transceiver local oscillator of each control station, while the first phase transceiver of each control station provides a phase rotation of -90 °, and the second phase transceiver of the central control station provides a phase rotation of + 90 °.

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