RU2389054C1 - Method for collation of time scales and device for its implementation - Google Patents

Abstract

FIELD: means of communication.

SUBSTANCE: board equipment of movable object comprises standard of frequency and time, synthesiser of the first heterodyne frequencies, synthesiser of the second heterodyne frequencies, generator of pseudonoise signal, switch, element, the first mixer, amplifier of the first intermediate frequency, the first power amplifier, duplexer, transceiving antenna, the second power amplifier, the second mixer, amplifier of the second intermediate frequency, the first and second clippers, the first and second buffer memorising devices, metre of delays and their derivatives, multiplier, band filter, phase detector, board controller, driving oscillator, phase manipulator, receiving antenna, power amplifier, mixer, amplifier of the second intermediate frequency, multiplier, band filter, phase detector, sensors and board register. Ground centre of management and control comprises standard of frequency and time, synthesiser of the third heterodyne frequencies, synthesiser of the fourth heterodyne frequencies, generator of pseudonoise signal, switch, element OR, two mixers, amplifier of the first intermediate frequency, two power amplifiers, duplexer, transceiving antenna, amplifier of the second intermediate frequency, two clippers, two buffer memorising devices, metre of delays and their derivatives, multiplier, band filter, phase detector, ground controller, reference synthesise of bearing frequency, phase manipulator, the second synchroniser, the second generator of pseudorandom code.

EFFECT: improved reliability and credibility of messages exchange between movable object and control centre, control in conditions of organiser and unintentional noise, multi-beam distribution of radio waves by means of pseudorandom tuning of working frequency.

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Description

The proposed method and device relates to the field of communications and signaling and can be used to compare time scales spaced over a long distance and placed on vehicles and ground control and monitoring center, and for remote monitoring of the technical condition of the vehicle and its location on ground management and control.

Known methods and devices for clock synchronization (ed. Certificate No. 591799, 614416, 970300, 1180835, 1244632, 1278800; RF patents No. 2001423, 2003157, 2040035, 2177167, 2301437; BC Gubanov, AM Finkelshtein, P.A. Fridman Introduction to radio astronomy. - M., 1983 and others).

Of the known methods and devices for clock synchronization, the closest to the proposed are the "Method of comparing time scales" (patent No. 2301437, G04C 11/02, 2005) and a device for its implementation, which are selected as the base objects.

These technical solutions provide a comparison of time scales spaced over long distances, and are based on the use of the duplex method of communication through a geostationary satellite repeater.

The main advantage of the duplex communication method is that it eliminates the length of the signal path. Therefore, its accuracy mainly depends on the parameters of the onboard transponder, the type of signal used, and the technique for measuring time intervals.

The known method and device allows you to remotely monitor from the control center and control the behavior of a moving object, the operation of its systems and the action of the crew, as well as remotely monitor the technical condition of a moving object and its location.

At the same time, space, air, water and land vehicles can be used as moving objects.

However, in the conditions of organized and unintentional interference, multipath propagation of radio waves, reliable messaging between mobile objects and the control and monitoring center causes certain difficulties.

To a certain extent, the problem of the exchange of messages between mobile objects and the control and monitoring center under the conditions of organized and unintentional interference, multipath propagation of radio waves can be solved by pseudo-random tuning of the operating frequency (MFC).

An object of the invention is to increase the reliability and reliability of the exchange of messages between moving objects and the control and monitoring center in the conditions of organized and unintentional interference, multipath propagation of radio waves by pseudo-random tuning of the operating frequency.

The problem is solved in that a method of comparing time scales, based, in accordance with the closest analogue, on the simultaneous reception by separated points of noise microwave signals from an artificial Earth satellite (AES), coherently converting them to a video frequency, digitally recording the received signals and determining the time delays in the arrival of the same signal to synchronization points by the method of correlation processing of registered signals, the magnitude of which compares time scales, while in the initial the first moment of time t _1, according to the clock of the first point, a microwave noise signal is generated using a code sequence, it is recorded at the same point, the generated signal is converted into a signal with a frequency of ω ₁ , it is amplified by power, the amplified signal is emitted in the direction to the satellite repeater , at the same time t _1, according to the clock of the second point, using the same code sequence form the same noise microwave signal, register it at the second point, receive the signal at the frequency ω ₁ onboard equipment of the satellite repeater, re-emission they transmit it to the first and second points at a frequency of ω ₂ while maintaining the phase relationships, at an arbitrary time t ₃ according to the clock of the second point, a noise microwave signal is generated and relayed similarly, the generated signal is converted into a signal at a frequency of ω ₁ , amplified by power, emit an amplified signal in the direction of the same satellite repeater, at the same time t ₃ according to the clock of the first point using the same code sequence form the same noise microwave signal, register it at the first point, take on-board device set up the satellite relay signal at a frequency of ω ₁ and re-emit it to the first and second points at a frequency of ω ₂ while maintaining phase relationships, the first point is placed on a moving object, which is used as a space, air, water or ground vehicle, and the second ground the point is used as a control and monitoring center, the coordinates of which are determined as a result of precision geodetic surveying, on a moving object, parameters are determined that determine its technical condition, they are recorded and form a in modulating code generating high frequency oscillation at frequency ω _s, manipulate its phase modulating code generated complex signal with the phase shift keying is converted in frequency using the first intermediate frequency voltage ω _pr1 = ω _c + ω _z1 where ω _r1 - frequency of the first LO, increase its power emit the amplified signal toward the satellite repeater re-emit it in the center of the control and monitoring at the frequency ω = ω ₁ = ω _{pr1 r2} where _r2 ω - frequency of the second local oscillator, while preserving phase relationships , Receiving a composite signal with a phase shift keying in the center of management and control, increase its power, frequency-converted using the first local oscillator is a voltage of the second intermediate frequency _np2 ω = ω ₁ = ω _r1 -ω _s, multiplies it with the voltage of the second oscillator, a complex signal with phase shift keying is emitted at a frequency ω _{g1 of the} first local oscillator, it is synchronously detected using the voltage of the first local oscillator as a reference voltage, a low-frequency voltage is proportional ally to the modulating code, and analyze it, similarly transmit discrete information from the control and monitoring center to a moving object, while on the moving object complex signals with phase shift keying emit at a frequency of ω ₂ , and in the center of control and control complex signals with phase shift keying emit at a frequency of ω ₂ and receive at a frequency of ω ₁ , at the same time on a moving object take a GPS signal at a frequency of ω ₂ , amplify it in power, convert in frequency using the voltage of the second local oscillator, output elyayut voltage of the second intermediate frequency _np2 ω = ω _z2 -ω _2, multiplies it with the voltage of the second local oscillator emit GPS-signal at the frequency ω _r1 of the first local oscillator, its synchronous detection is performed using a frequency ω _r1 of the first local oscillator emit low-frequency voltage, it is used to determine the location of the moving object and transmit information about the location of the moving object to the control and monitoring center, if all the measured parameters correspond to the normal operation condition object, and the location of the moving object - to the planned location, the transfer of discrete information from the board of the moving object to the ground control and monitoring center is carried out with a specified frequency, if at least one of the measured parameters exceeds the specified level or the location of the moving object deviates from the planned location the period between transmissions is reduced, and when an emergency is created, discrete information is continuously transmitted from the board of a moving object, when the parameters to acceptable values, as well as the correspondence of the location of the moving object to the planned location, the period between the transmission of discrete information is again increased, differs from the closest analogue in that the carrier frequency grids, the frequency grids of the first and second are formed on the moving object and in the control and monitoring center , of the third and fourth local oscillators, which consistently switch according to the law of the pseudo-random code, between successive switchings only one carrier frequency and the corresponding the corresponding frequencies of the frequency synthesizers of the first, second, third and fourth local oscillators and form a time interval t _c , which characterizes the operating time at one frequency and which contains n information symbols of duration τ _e

t _c = n · τ _e,

at each time interval t _c in the transmitter of the moving object, the high-frequency oscillations of the carrier frequency are manipulated in phase and frequency converted using the frequency grid of the first local oscillator, in the receiver of the moving object, the received signal is converted in frequency using the frequency grid of the second local oscillator and phase demodulated, and in the transmitter of the control and monitoring center they manipulate the high-frequency oscillations of the carrier frequency in phase and convert in frequency c and using the frequency grid of the fourth local oscillator, in the receiver of the control and monitoring center, the received signal is converted in frequency using the third local oscillator grid and phase demodulated.

The problem is solved in that the device for comparing time scales, containing, in accordance with the closest analogue, a geostationary satellite repeater, a moving object and a control and monitoring center, while the equipment of a moving object and a control and monitoring center contains a frequency and time standard connected in series , pseudo-noise signal generator, switch, OR element, first mixer, first intermediate frequency amplifier, first power amplifier, duplexer, the input-output of which is connected to the transceiver a second power amplifier, a second mixer, a second intermediate frequency amplifier, a second clipper, the second input of which is connected to the second output of the frequency and time standard, a second buffer storage device, a delay meter and their derivatives, a controller and a phase manipulator, the output of which is connected to the second input of the OR element, connected in series to the third output of the frequency and time standard, the first clipper, the second input of which is connected to the second output of the pseudo-noise signal generator, and the first a buffer memory device, the output of which is connected to the second input of the delay meter and their derivatives, connected in series to the output of the amplifier of the second intermediate frequency, a multiplier, a bandpass filter, and a phase detector, the output of which is connected to the second input of the controller, the equipment of the moving object is also equipped with sensors characterizing the technical condition of the moving object and connected to the on-board recorder and to the third input of the on-board controller, and a GPS signal receiver, consisting of a series-connected receiving antenna, power amplifier, mixer, second intermediate frequency amplifier, multiplier, band-pass filter and phase detector, the output of which is connected to the fourth input of the on-board controller, differs from the closest analogue in that it is equipped with two synchronizers, two pseudo-random code generators, two carrier frequency synthesizers, the first local oscillator frequency synthesizer, the second local oscillator frequency synthesizer, the third local oscillator frequency synthesizer and the synthesizer often t of the fourth local oscillator, and the first pseudorandom code generator and the first carrier frequency synthesizer, the output of which is connected to the second input of the first phase manipulator, are connected to the output of the first synchronizer of the moving object equipment, the second inputs of the first and second mixers are respectively connected to the frequency synthesizers of the first and second local oscillators the output of the first pseudo-random code generator, the second inputs of the frequency synthesizers of the first and second local oscillators are connected to the fourth output frequency and time standard, the second inputs of the phase detectors are connected to the output of the frequency synthesizer of the first local oscillator, the second inputs of the mixer and the multiplier of the GPS receiver are connected to the output of the frequency synthesizer of the second local oscillator, the second pseudo-random code generator is connected in series to the output of the second synchronizer of the control center equipment and the second carrier frequency synthesizer, the output of which is connected to the second input of the second phase manipulator, the second inputs of the third and fourth mixers through frequency synthesizers of the third and fourth local oscillators are respectively connected to the output of the second pseudo-random code generator, the second inputs of the multiplier and phase detector are connected to the outputs of the frequency synthesizers of the third and fourth local oscillators, respectively.

The geometric arrangement of the moving software object, the ground control and monitoring center of the CCM, the satellites of the GPS navigation system and the satellite repeater S is shown in figure 1, where the following notation is introduced: O is the center of mass of the Earth; d is the base of the interferometer; r is the radius vector of the satellite repeater placed in a geostationary orbit. A frequency diagram explaining signal conversion is depicted in FIG. 2. The block diagram of a moving software object is presented in figure 3. The structural diagram of the ground control center and control of the CMS is shown in Fig.4. Timing diagrams explaining the operation of a moving object, a ground control and monitoring center and a GPS receiver are shown in FIGS. 5, 6, 7. A timing diagram of the duplex clock comparison method is shown in FIG. 8, where the following notation is introduced: S, A, B is the time scale of the satellite repeater, the software mobile object, and the ground control and monitoring center of the CMS, respectively. A fragment of the time-frequency matrix of the used PSK signals with frequency hopping is shown in Fig.9.

The on-board equipment of a moving object contains a frequency and time standard 1.1 in series, a pseudo-noise signal generator 1.4, a switch 1.5, an OR element 1.6, a first mixer 1.7, the second input of which is connected to the output of the first frequency synthesizer 1.2 of the first local oscillator, amplifier 1.8 of the first intermediate frequency, first amplifier 1.9 power, duplexer 1.10, the input-output of which is connected to the transceiver antenna 1.11, the second power amplifier 1.12, the second frequency mixer 1.3 of the second local oscillator, the amplifier 1.14 of the second intermediate 1st frequency, clipper 1.16, second buffer memory 1.18, delay 1.19 meter and their derivatives, on-board controller 1.23 and phase manipulator 1.25, the output of which is connected to the second input of the 1.6 element OR, connected in series to the third output of the standard 1.1 frequency and time clipper 1.15, the second input of which is connected to the second output of the generator 1.4 of the pseudo-noise generator, and the first buffer memory 1.17, the output of which is connected to the second input of the meter 1.19, delays and their derivatives, is connected in series the output of the amplifier 1.14 of the second intermediate frequency, the multiplier 1.20, the second input of which is connected to the output of the synthesizer 1.3 of the frequencies of the second local oscillator, the bandpass filter 1.21 and the phase detector 1.22, the second input of which is connected to the output of the synthesizer 1.2 of the frequencies of the first local oscillator, and the output is connected to the second input the on-board controller 1.23, to the third input of which the output of the sensors 26 characterizing the technical condition of the moving object is connected, the on-board recorder 27 is connected to the output of the sensors 26, the first connected in series synchronizer 28, the first pseudo-random code generator 29, and the first carrier frequency synthesizer 1.24, the output of which is connected to the second input of the phase manipulator 1.25, the output of the pseudo-random code generator 29 is connected to the second input of the frequency synthesizers 1.2 and 1.3 of the first and second local oscillators, the second inputs of which are connected to the fourth output standard 1.1 frequency and time.

The GPS signal receiver contains a series-connected receiving antenna 1.28, a power amplifier 1.29, a mixer 1.30, the second input of which is connected to the output of the second frequency oscillator synthesizer 1.3, an second intermediate frequency amplifier 1.31, a multiplier 1.32, the second input of which is connected to the output of the second frequency oscillator synthesizer 1.3 , a band-pass filter 1.33 and a phase detector 1.34, the second input of which is connected to the output of the frequency synthesizer 1.2 of the first local oscillator, and the output is connected to the fourth input of the on-board controller 1.23.

The ground control and control center contains sequentially connected frequency and time standard 2.1, a pseudo noise signal generator 2.4, a switch 2.5, an OR element 2.6, a third mixer 2.7, the second input of which is connected to the fourth output of the frequency and time standard 2.1 through a 2.2 frequency synthesizer of the third local oscillator Amplifier 2.8 of the first intermediate frequency, third power amplifier 2.9, duplexer 2.10, the input-output of which is connected to the transceiver antenna 2.11, the fourth amplifier 2.12, the mixer 2.13, the second input of which synthesizer 2.3 frequencies of the fourth local oscillator connected to the fourth output of standard 2.2 frequency and time, amplifier 2.14 of the second intermediate frequency, clipper 2.16, the second input of which is connected to the second output of standard 2.1 frequency and time, buffer memory 2.18, meter 2.19 delays and their derivatives, ground 2.23 controller and 2.25 phase manipulator, the output of which is connected to the second input of the 2.6 element OR, connected in series to the third output of the frequency and time standard 2.1, clipper 2.15, the second input of which is connected to W a direct output of the pseudo-noise signal generator 2.4, and a buffer memory 2.17, the output of which is connected to the second input of the delay meter 2.19 and their derivatives, a multiplier 2.20, the second input of which is connected to the output of the third frequency oscillator synthesizer 2.2, sequentially connected to the output of the second intermediate frequency amplifier 2.14, a bandpass filter 2.21 and a phase detector 2.22, the second input of which is connected to the output of the frequency synthesizer 2.3 of the fourth local oscillator, and the output is connected to the second input of the ground controller 2.23, therefore, the second synchronizer 30, the second pseudo-random code generator 31 and the second carrier frequency synthesizer 2.24 are turned on, the output of which is connected to the second input of the phase manipulator 2.25, the second inputs of the third and fourth local oscillator synthesizers 2.2 and 2.3 are connected to the output of the second pseudo-random code generator 31.

As a moving object use a space, air, water or land vehicle.

The proposed method of comparing time scales is implemented as follows. In the first step of single measurements at a time t ₁ ^A by the clock of a moving software object, the pseudo-noise signal α ₁ (Fig. 8), created by the generator 1.4 using the frequency and time standard 1.1, is converted using a local oscillator 1.2, a mixer 1.7, and an amplifier 1.8 a first intermediate frequency signal with a frequency ω _1i, amplified by a power amplifier 1.9 and 1.10 radiate through the duplexer and a transceiver antenna in the direction 1.11 satellite repeater S. However, the same signal klippiruyut in Clipper 1.15 clocked at the same standard 1.1 and the frequency written in the buffer memory 1.17. Registration is synchronized with frequency and time standard 1.1.

At the same time t ₁ ^A = t ₁ ^B according to the clock of the ground-based control and monitoring center of the central control center, using the same code sequence, they generate the same noise microwave signal (signal β ₁ ), register, but do not send for registration (switch 2.5 open ) They take a signal at the frequency ω _1i (signal α ₁ ) onboard the satellite transmitter’s equipment, re-emit it to a moving object and a ground control and monitoring center at a frequency ω _2i while maintaining phase relationships, receive a relay signal at both points, convert it to a signal at a video frequency register at time t ₂ ^A and t ₂ ^B, respectively (signals α ₂ , β ₂ ).

In the second step (when transmitting a signal from the control and monitoring center), switch 1.5 must be open, switch 2.5 is closed, and signal α ₃ from generator 1.4 is transmitted through clipper 1.15 to the same memory device 1.17.

At an arbitrary point in time t ₃ ^B = t ₂ ^B + Θ, the noise of the microwave signal (β ₃ signal) is similarly generated and recorded by the hours of the second point. Onboard equipment of a satellite repeater receives a signal at a frequency of ω ₁ (signal α ₃ ), re-emits it to points A and B at a frequency of ω _2i while maintaining phase components, receives a relay signal at both points, converts it to signals at a video frequency, records at times time t ₄ ^A and t ₄ ⁸ respectively (signals α ₄ and β ₄ ).

The correlation processing of two pairs of registered signals in the interval between the measurement acts in meters 1.19 and 2.19 determines the following time delays and their derivatives:

where F _i is the frequency of interference (i = 1, 2, 3, 4);

a _j , b _j , (j> 1, 2, 3) - signal propagation time between the satellite and points A and B, respectively;

- задержки сигналов в излучающей аппаратуре обоих пунктов;

- signal delays in the radiating equipment of both points;

- задержки сигналов в приеморегистритующей аппаратуре;

- signal delays in the receiver-recording equipment;

ΔS - signal delay in the onboard equipment of the satellite repeater;

Δt = t _B -t _A is the desired difference in the clock readings at the same physical moment.

получим:Assuming a _j and b _j linear functions with derivatives

we get:

Where

- задержки сигналов в атмосфере на частоте f₁ и f₂ соответственно;

- delays of signals in the atmosphere at a frequency f ₁ and f _2, respectively;

ν - relativistic correction (Sagnac effect);

ω is the angular velocity of the Earth;

c is the speed of light;

D is the area of the quadrilateral O'A'S'B ', formed in the equatorial plane by the center of mass of the Earth, the projections of points A, B and

AES - repeater.

The correction γ for the mobility of the satellite repeater during a single measurement is most easily reduced to zero by the appropriate choice of the free parameter Θ:

which should be calculated at the beginning of measurements by approximate ephemeris data, and then clarified by the results of current measurements.

Regarding the correction δ, hardware delays. Then it can be found by calibration using the "zero base" method. The atmospheric correction ε is also taken into account.

In points A and B, the equipment works the same way, only the order of steps in them is the opposite. To calculate the difference of the clock readings Δt, it is enough to exchange the received digital data between the points, which can be done via ordinary telephone or telegraph communication channels. The results of the comparison are sent to the airborne 1.23 and ground-based 2.23 controllers.

In the process of moving a movable object, sensors 26 located in various places of the vehicle (engine compartment, housing, control system, fuel tanks, etc.) transmit information about the state of the monitored vehicle components to the on-board recorder 27, which can be made in the form tape recorders, optical media, paper, etc.

At the same time, this information is fed to the second input of the on-board controller 1.23, to the third input of which information on the location of the moving object received from the GPS signal receiver is supplied. The latter consists of a receiving antenna 1.18, a power amplifier 1.29, a mixer 1.30, the second input of which is connected to the output of the second intermediate frequency amplifier 1.31, a multiplier 1.32, the second input of which is connected to the output of the band-pass filter 1.33 and and phase detector 1.34, the second input of which is connected to the output a synthesizer 13 frequencies of the second local oscillator, and the output is connected to the third input of the on-board controller 1.23.

The Global Positioning System (GPS) includes a space segment consisting of 24 satellites, a network of ground-based monitoring stations for their operation, and a user segment — GPS receivers.

Each GPS satellite emits at a frequency of ω ₂ = 1575 MHz a special navigation signal in the form of a binary phase-manipulated (PSK) signal, phase-manipulated by a pseudorandom sequence of 1023 characters in length (Fig. 7a):

where φ _k (t) = {0, π} is the manipulated phase component that displays the law of phase manipulation in accordance with a pseudo-random sequence of duration N = 1023.

This signal is received by the antenna 1.28 and through the power amplifier 1.29 is fed to the first input of the mixer 1.30, the second input of which is supplied with the voltage of the frequency synthesizer

At the output of the mixer 1.30, voltages of combination frequencies are generated. Amplifier 1.31 distinguishes the voltage of the second intermediate frequency (Fig.7b)

Where

K ₁ - gear ratio of the mixer;

ω _pr2i = ω _{g2i -ω 2i} is the second intermediate frequency;

φ _pr2i = φ _2i -φ _g2i ,

which goes to the first input of the multiplier 1.32. The second input of the latter is supplied with voltage u _r2 (t) of the frequency synthesizer. At the output of the multiplier, a voltage is generated (Fig. 7c)

Where

K ₂ is the transmission coefficient of the multiplier;

which is an FMN signal at a frequency ω _{g1 of the} local oscillator 1.2 and is fed to the first (information) input of the phase detector 1.34. A frequency synthesizer voltage is applied to the second (reference) input of the phase detector 1.34 as a reference voltage

As a result of synchronous detection at the output of the phase detector 1.3, a low-frequency voltage is generated (Fig.7g)

Where

K ₃ - the transfer coefficient of the phase detector,

which goes to the third input of the on-board controller 1.23, where the location of the moving object (latitude and longitude) is determined. For this, the presence of three satellites in the radio visibility zone is sufficient. The accuracy of determining the location of a moving object is 50 ... 80 m.

One of the main methods for increasing the accuracy of determining the location of a moving object and eliminating errors associated with the introduction of selective access mode is based on the application of the principle of differential navigation measurements, known in radio navigation.

The differential mode allows you to set the coordinates of the vehicle with an accuracy of 5 m in a dynamic navigation environment and up to 2 m in static.

On-board controller 1.23, configured to program the time between radio sessions, depending on the magnitude of the parameters measured by the sensors 26. With a specified frequency (for example, 30 minutes), the received information (location, event protocol, technical condition, essence of the emergency situation, if it arose, as well as the full trajectory of the inter-session satellite) is transmitted through the onboard satellite communications segment, the satellite repeater and the terrestrial satellite communications segment gap) to the ground control and control center.

To this end, using the first synchronizer 28, the first pseudo-random code generator 29 is turned on, which, in turn, controls the operation of the first synthesizer 1.24 of the carrier frequencies, the synthesizer 1.2 of the frequencies of the first local oscillator and the synthesizer 1.3 of the frequencies of the second local oscillator.

At the output of the first synthesizer 1.24 carrier frequencies, a grid of high-frequency oscillations of various carrier frequencies is formed sequentially in time:

.....................

.....................

where U _i , ω _i , φ _i , T _c - amplitudes, carrier frequencies, initial phases and signal duration;

i = 1, 2, ..., M,

M is the number of carrier frequencies used (number of frequency channels);

Δω _c is the bandwidth of the spread spectrum with the signal used (Fig.9);

Δω ₁ is the bandwidth of one frequency channel;

t _c - the time interval between frequency switching, characterizes the operating time at one carrier frequency.

Depending on the ratio of the operating time at one frequency t _c and the duration of the information signals τ _{e, the} pseudo-random tuning of the working frequency (PFRCH) can be divided into: intersymbol, character and character.

When intersymbol frequency hopping n information symbols (n≥2) are transmitted at the same frequency, with t _c = n · τ _e .

As an example, Fig.9 shows a fragment of the time-frequency matrix of a complex signal with phase shift keying (PSK). In this case, n is chosen equal to 4 (t _c = 4τ _e ), squares with different oblique shading indicate different information symbols with different phases (0, π).

The generated high-frequency oscillations sequentially in time arrive at the first input of the phase manipulator 1.25, the second input of which is supplied from the output of the on-board controller 1.23, the manipulating code M ₁ (t) (Fig.5b) containing information about the technical condition of the moving object and its location. 5a shows i-oe high frequency oscillation. At the output of the phase manipulator 1.25, a complex QPSK signal is generated (Fig.5c)

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.5b), and φ _k1 (t) -const

for kτ _e <t <(k + 1) τ _e and can change stepwise at t = kτ _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 _c (T _c = Nτ _e ),

which through the element OR 1.6 enters the first input of the mixer 1.7. The second input of the mixer 1.7 from the output of the synthesizer 1.2 frequencies of the first local oscillator voltage is applied sequentially in time:

..........................

..........................

which are formed sequentially in time using the pseudo-random code generator 29.

At the output of mixer 1.7, voltages of combination frequencies are generated. Amplifier 1.8 is allocated voltage only the first intermediate (total) frequency (Fig.5g)

Where

ω _PR1i = ω _i + ω _Г1i - the first intermediate (total) frequency ( _figure 2);

φ _PR1i = φ _i + φ _Г1i ,

which, after amplification in the power amplifier 1.9, through the duplexer 1.10 enters the transceiver antenna 1.11, it is broadcasted in the direction of the satellite, relayed by it at the same frequency while maintaining the phase relationships, it is received by the antenna 2.11 of the ground control and control center and through the duplexer 2.10 and the power amplifier 2.12 is supplied to the first input of the mixer 2.13, the second input of which is supplied with the voltage u _Г1i (t) of the synthesizer 2.3 of the frequencies of the fourth local oscillator (i = 1, 2, ..., M). At the output of the mixer 2.13, voltages of combination frequencies are generated. Amplifier 2.14 allocated voltage of the second intermediate (differential) frequency (Fig.5d)

Where

ω _PR2i = ω _{PR1i -ω Г1i} is the second intermediate (difference) frequency;

φ _PR2i = φ _PR1i -φ _Г1i

which goes to the first input of the multiplier 2.20. The second input of the multiplier 2.20 is fed to the voltage of the synthesizer 22 frequencies of the third local oscillator:

...........................

...........................

At the output of the multiplier 2.20 a voltage is generated (Fig.5e)

Where

ω _G1i = ω _PRi = ω _{G2i -ω PR2i} is the intermediate frequency, which is allocated by the band-pass filter 2.21 and arrives at the first (information) input of the phase detector 2.22. At the second (reference) input of the phase detector 2.22, voltages u _Г1i (t) of the frequency synthesizer 23 of the fourth local oscillator are supplied as reference voltages, which are generated sequentially in time using a pseudorandom code generator 31 controlled by a synchronizer 30. As a result of synchronous detection at the output of the phase detector 2.22 low-frequency voltage is generated (FIG. 5g)

Where

which goes to the second input of the ground controller 2.23.

Based on the results of the analysis of the situation by the ground controller 2.23 at the ground control and control center, an appropriate decision is made, for example, to turn off the faulty engine, or recommendations are made to the crew on actions in case of emergencies.

To transmit these commands in the ground controller 2.23, a modulating code M ₂ (t) is generated (Fig.6b), which is fed to the second input of the phase manipulator 2.25. The first input of the latter is supplied with a high-frequency oscillation from the output of the synthesizer 2.24 carrier frequencies controlled by the generator 31 of the pseudo-random code, to the control input of which a synchronizer 30 is connected

At the output of the phase manipulator 2.25, a complex QPSK signal is generated (Fig.6c)

where φ _k2 (t) = {0, π} is the phase component being manipulated in accordance with the modulating code M ₂ (t) (Fig.6b), which, through the OR 2.6 element, enters the first input of mixer 2.7. The voltage u _Г2i (t) of the synthesizer 2.2 of the frequency of the third local oscillator is fed sequentially to the second input of the mixer 2.7. At the output of the mixer 2.7, voltages of combination frequencies are generated. The amplifier 28 is allocated the voltage of the intermediate frequency (Fig.6g)

Where

ω _PRi = ω _Г2 -ω _i = ω _2i - intermediate frequency;

φ _4i = φ _i -φ _Г2i ,

Which, after amplification in the power amplifier 2.9 through the duplexer 2.10, enters the transceiver antenna 2.11, is emitted by it in the direction of the satellite of the repeater at the frequency ω _2i , is reradiated by the botanical equipment of the satellite of the relay with preservation of phase relations, it is received by the antenna 1.11 of the moving object and through the duplexer 1.10 and the amplifier 1.12 power is supplied to the first input of the mixer 1.13, the second input of which is supplied sequentially in time to the voltage u _Г2i (t) of the frequency synthesizer 1.3 of the second local oscillator. At the output of the mixer 1.13, voltages of combination frequencies are formed. Amplifier 1.14 distinguishes the voltage of the second intermediate frequency (Fig.6d)

Where

ω _PR2i = ω _{Г2i -ω 2i} is the second intermediate frequency;

φ _6i = φ _4i -φ _Г2i ,

which goes to the first input of the multiplier 1.20. The second input of the latter is supplied with voltage u _Г2i (t) of the synthesizer 1.3 of the frequencies of the second local oscillator. At the output of the multiplier 1.20, a voltage is generated (Fig.6e)

Where

ω _PRi = ω _{Г2i -ω PR2i} - intermediate frequency;

φ _7i = φ _6i -φ _Г2i ,

which is allocated by the band-pass filter 1.21 and arrives at the first input of the phase detector 1.22. At the second (reference) input of the phase detector 1.22, voltages u _Г1i (t) of the frequency synthesizer 1.2 of the first local oscillator are supplied as reference voltages. As a result of synchronous detection at the output of the phase detector 1.22, a low-frequency voltage is generated (Fig.6zh)

Where

which goes to the fourth input of the on-board controller 1.23, where the commands and recommendations of the ground control and monitoring center are implemented.

If all the parameters measured by the sensors 26 correspond to the conditions of normal operation of the moving object, and the location of the moving object corresponds to the planned location, the transmission of discrete information from the board of the moving object to the ground control and monitoring center occurs at a predetermined frequency (for example, once every 30 minutes) .

If at least one of the measured parameters of a given level is exceeded or the location of the moving object deviates from the planned location, the period between transfers is reduced.

When creating an emergency, discrete information from the board of a moving object is transmitted continuously.

The mode of transmission of discrete information by the on-board controller 1.23 can also be changed by a decision of the command staff of a moving object or by a ground control and control center.

When the controlled parameters return to acceptable values, as well as the correspondence of the location of the moving object to the planned location, the period between the transmission of discrete information will again be increased.

Thus, the proposed method and device in comparison with prototypes and other technical solutions of a similar purpose provide increased reliability and reliability of the exchange of messages between a moving object and a control and monitoring center in the conditions of organized and unintentional interference, multipath propagation of radio waves. This is achieved by pseudo-random tuning of the operating frequency of the used complex signals with phase shift keying.

The operating frequency of the used PSK signals and the frequency of the local oscillators are tuned over a wide range in accordance with pseudorandom codes known at the moving object and at the control and monitoring center and unknown to the jammer.

The strategy to combat unintentional and organized interference in the proposed method and device consists in “avoiding” the signals of the duplex radio communication system from the effects of interference by pseudo-random tuning of the operating frequency and in “confronting” them by phase manipulating the carrier frequency with a pseudo-random sequence (PSP).

Therefore, when protecting against interference, an important characteristic is the actual operating time at one frequency t _c . The shorter this time, the higher the likelihood that the signals of a duplex radio communication system with frequency hopping will not be affected by organized interference.

The noise immunity of a duplex radio communication system depends not only on the operating time at one frequency, but also on the type of interference and their power, useful signal power, and receiver structure.

The complex PSK signals with frequency hopping used in terms of detection and reconnaissance have energy, structural, informational, temporal and spatial 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 PSK signal with frequency hopping 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 in this area the signal power is less than the power of noise and interference.

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

Information secrecy is determined by the ability to withstand measures of electronic intelligence aimed at revealing the meaning of messages exchanged between a moving object and a control and control center.

The temporary secrecy of a duplex radio communication system is determined by the possibility of radio reconnaissance of a likely adversary and the collection of necessary information about a duplex radio communication system (type and parameters of signals, the purpose of a duplex radio communication system, etc.) for a certain time and depends on the conditions in which a duplex radio communication system is used, its temporary modes of operation for radiation, the tactical and technical characteristics of a radio intelligence station and the nature of intelligence.

The spatial secrecy of a duplex radio communication system characterizes the ability to interfere with a radio intelligence station with the necessary accuracy to determine the direction of arrival of signals (or the location of a moving object). The spatial secrecy of a duplex radio communication system depends on a number of parameters of the duplex radio communication system, for example, signal strength, type and parameters of radiation patterns of transceiver antennas.

Complex QPSK signals with frequency hopping 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.

Among other problems, the solution of which to a large extent depends on the further progress of duplex radio communications, should include the problem of establishing reliable communication between a moving object and a control and monitoring center in the presence of a multipath nature of radio wave propagation. The presence of the multipath nature of the propagation of radio waves leads to a distortion of the received signals, which complicates the reception and reduces the reliability of the transmission of information.

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 the use of several carrier frequencies and its good correlation properties, a complex QPSK signal with frequency hopping frequency can be “folded” into a narrow pulse, the duration of which is inversely proportional to the used bandwidth. Choosing such a frequency band so that the duration of the “convoluted” pulse is less 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 receiving PSK signals with frequency hopping. Thus, the indicated problem gets a fundamental solution.

The proposed technical solutions can be used to control flight operations by air and sea vehicles, to control the exercises of long-range aviation and the navy, during the flight of manned spaceships and artificial Earth satellites, to ensure testing of aviation and marine equipment beyond the sight of the facilities of test bases, to control the work of inexperienced crews and worn equipment.

The use of a duplex radio communication system allows you to make a decision on actions in emergency situations at the time of their occurrence, to transmit recommendations on actions for the development of emergency situations, to give instructions to the rescue service in case of adverse development of emergency situations, to give accurate target designation to search for a vehicle that has crashed.

Claims (2)

1. A method of comparing time scales based on the simultaneous reception of separated microwave noise signals from an artificial Earth satellite, their coherent conversion to a video frequency, digital recording of received signals and determining the time delay of the arrival of the same signal to synchronization points by correlation processing of recorded signal, the magnitude of which produce a comparison of time scales, with the initial time t ₁ to the first clock item using the code posledovatelnos and generating noise microwave signal, record it on the same point, the conditioned signal is converted into a signal with a frequency ω _1, increase its power emit the amplified signal in the direction of the artificial satellite of the Earth - a repeater in the same time t ₁ hours of the second point using the same code sequence form the same noise microwave signal, register it at the second point, receive the signal at the frequency ω ₁ onboard equipment of the artificial Earth satellite-relay, re-emit it to the first and second points at a frequency of ω ₂ while maintaining phase relationships, at an arbitrary time t ₃ according to the clock of the second point, similarly generate and relay a noise microwave signal, the generated signal is converted into a signal at a frequency of ω ₁ , amplify it by power, emit an amplified signal in the direction the artificial satellite - repeater in the same time point t _3, the clock of the first item by using the same code sequence form the same noise microwave signal, retransmit it to the first item, taking sides appa Aturi artificial satellite - transponder signal at frequency ω ₁ and re-emit it at first and second points at the frequency ω ₂ while preserving phase relationships, the first point is placed on a movable object, which is used as space, air, water or land vehicle, and the second ground station is used as a control and monitoring center, the coordinates of which are determined as a result of precision geodetic surveying; parameters are measured on a moving object that determine its technical -being, register them, and converted to baseband code generating high frequency oscillation at frequency ω _s, manipulate its phase modulating code generated complex signal with the phase shift keying is converted in frequency using the voltage of the first local oscillator is isolated voltage of the first intermediate frequency ω _pr1 = ω _{c r1} + ω, where ω _r1 - first local oscillator frequency, increase its power emit the amplified signal toward the artificial satellite - repeater re-emit it to the control center and counter la at the frequency ω ₁ = ω _pr1 = ω _r2, where ω _z2 - frequency of the second local oscillator, while preserving phase relationships, receiving a composite signal with a phase shift keying in the center of management and control, increase its power, converted by frequency using a first local oscillator, isolate the voltage of the second intermediate frequency ω _p2 = ω ₁ -ω _g1 = ω _c - multiply it with the voltage of the second local oscillator, isolate a complex signal with phase shift keying at the frequency ω _{g1 of the} first local oscillator, perform its synchronous detection using the voltage ne of the local oscillator as a reference voltage, a low-frequency voltage proportional to the modulating code is isolated and analyzed, similarly, discrete information is transmitted from the control and monitoring center to a moving object, and complex signals with phase shift keying emit at a frequency ω ₁ on a moving object, and receiving at frequency ω _2, and the center control and monitoring of complex signals with a phase shift keying radiate at frequency ω _2, and receiving at the frequency ω _1, simultaneously on the mobile object receiving GPS- Igna at frequency ω _2, increase its power, frequency converted using the second voltage LO isolated voltage of the second intermediate frequency _np2 ω = ω _z2 -ω _2, multiplies it with the voltage of the second local oscillator emit GPS-signal at the frequency ω _z1 first local oscillator, carry out its synchronous detection using the frequency ω _{g1 of the} first local oscillator, select a low-frequency voltage, use it to determine the location of a moving object and transmit information about the location of the moving object to the control and monitoring center, if all the measured parameters correspond to the conditionally normal operation of the moving object, and the location of the moving object corresponds to the planned location, discrete information is transmitted from the mobile object to the ground control and control center at a specified frequency, if at least one from the measured parameters of a given level or deviation from the location of the moving object from the planned location, the period between transfers is reduced, and When creating an emergency, discrete information is continuously transmitted from the board of the moving object, when the controlled parameters return to acceptable values, as well as the correspondence of the location of the moving object to the planned location, the period between the transmission of discrete information is again increased, characterized in that on the moving object and in the control center and control form the grid of carrier frequencies, the frequency grid of the first, second, third and fourth local oscillators, which consistently switch according to the law of pseudo osluchaynogo code between successive switchings use only one carrier frequency and the corresponding frequency synthesizers of frequencies of the first, second, third and fourth oscillators and generating timeslot t _c, which characterizes the operating time on the same frequency and that contains n information symbols of duration τ _e t _{c e} = nτ, at each time interval t _c of the transmitter of the movable object manipulation is performed a high-frequency oscillations of the carrier frequency in phase and frequency conversion with Execu by calling the frequency grid of the first local oscillator, in the receiver of the moving object, the received signal is converted in frequency using the frequency grid of the second local oscillator and phase demodulated, and in the transmitter of the control and control center, the high-frequency carrier frequency oscillation in phase and frequency conversion using the frequency grid are manipulated of the fourth local oscillator, in the receiver of the control and monitoring center, the received signal is converted in frequency using the frequency grid the third local oscillator and a phase demodulation. 2. A device for comparing time scales containing a geostationary satellite repeater, a moving object and a control and monitoring center, while the equipment of a moving object and a control and monitoring center contains a frequency and time standard, a pseudo-random signal generator, a switch, an OR element, a mixer, an amplifier of the first intermediate frequency, a first power amplifier, a duplexer, the input-output of which is connected to a transceiver antenna, a second power amplifier, a second mixer, an amplifier a second intermediate frequency, a second clipper, the second input of which is connected to the second output of the frequency and time standard, a second buffer memory, a delay meter and their derivatives, a controller and a phase manipulator, an output of an OR element connected in series to the third output of the frequency and time standard, the first clipper , the second input of which is connected to the second output of the pseudo-random signal generator, and the first buffer storage device, the output of which is connected to the second input of the delay meter and their a multiplier, a bandpass filter and a phase detector, the output of which is connected to the second input of the controller, the equipment of the moving object is also equipped with sensors characterizing the technical condition of the moving object and connected to the on-board recorder and to the third input on-board controller, and a GPS signal receiver, consisting of a series-connected receiving antenna, power amplifier, mixer, second-gap amplifier full-time frequency, multiplier, band-pass filter and phase detector, the output of which is connected to the fourth input of the onboard controller, characterized in that it is equipped with two synthesizers of carrier frequencies, a frequency synthesizer of the first local oscillator, a frequency synthesizer of the second local oscillator, a frequency synthesizer of the third local oscillator and a frequency synthesizer of the fourth local oscillator moreover, the first pseudo-random code generator and the first carrier synthesizer are connected in series to the output of the first synchronizer of the equipment of the moving object x frequencies, the output of which is connected to the second input of the first phase manipulator, the second inputs of the first and second mixers through the frequency synthesizers of the first and second local oscillators are respectively connected to the output of the first pseudo-random code generator, the second inputs of the frequency synthesizers of the first and second local oscillators are connected to the fourth output of the frequency standard and time, the second outputs of the phase detectors are connected to the output of the frequency synthesizer of the first local oscillator, the second inputs of the multiplier and the mixer and multiplier of the GP receiver S-signals are connected to the output of the frequency synthesizer of the second local oscillator, the second pseudorandom code generator and the second carrier frequency synthesizer, the output of which is connected to the second input of the second phase manipulator, the second inputs of the third and fourth mixers through synthesizers are connected to the output of the second synchronizer of the equipment of the control and monitoring center equipment the frequencies of the third and fourth local oscillators are connected to the output of the second pseudo-random code generator, the second inputs of the multiplier and phase detector are connected Nena frequency synthesizers to the outputs of the third and fourth oscillators, respectively.

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