RU2624634C1 - Method of determining speed of distribution and direction of ionospheric perturbation - Google Patents

Abstract

FIELD: physics.

SUBSTANCE: invention can be used to control solar, geomagnetic and seismic activity, earthquake precursors, volcanic eruptions, tsunamis, thunderstorm activity, the dynamics of powerful storm cyclones, as well as to detect nuclear and other large explosions and fires, large accidental discharges to Nuclear power stations, launches of comic devices and rockets, radiations of powerful radio transmitting complexes of radar and communication purpose, special impact on the ionosphere with the target to control its parameters. The method is realized by satellite radio navigation systems GLONASS/GPS and an extended grating of two-frequency receivers that provide reception and processing of signals.

EFFECT: increasing the detection sensitivity and accuracy of determining the propagation velocity and direction of arrival of the ionospheric disturbance detected by the two-frequency receivers of the satellite radio navigation system GLONASS by suppressing false signals received via additional channels and eliminating the phenomenon of reverse operation.

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Description

The proposed method relates to the field of radiophysics and can be used to monitor solar, geomagnetic and seismic activity, the precursors of earthquakes, volcanic eruptions, tsunamis, thunderstorm processes, the dynamics of powerful storm cyclones, as well as to detect nuclear and other major explosions and fires, large accidental emissions at nuclear power plants, launches of comic devices and rockets, emissions of powerful radio-transmitting complexes of radar and communication purposes, special equipment Nogo influence on the ionosphere to control its parameters etc.

Known methods for determining the direction of arrival and speed of movement of ionospheric disturbances of a natural and technogenic nature (ed. Certificate of the USSR No. 1,451.688, 1.709.263; RF patents No. 2.003.136, 2.085.965, 2.189.051 2.189.052, 2.193.495 , 2.267.139, 2.379.709, 2.560.094; U.S. Patent Nos. 4,761,650, 6,061.013; EP Patents Nos. 6,622,639; WO Nos. 1,045,195; Afraimovich EL, Kosogorov Ε.Α., Perevalova Ν.Ν The use of GPS arrays in defecting shoch-acoustic waves generated during rocket launchings. J. Atmos. Solar-Terr. Phys., V63, 1941-1957, 2001 and others).

Of the known methods closest to the proposed one is the "Method for determining the propagation velocity and direction of arrival of the ionospheric disturbance" (RF patent No. 2.560.094, G01S 13/95, 2013), which is selected as a prototype.

The known method provides an increase in the detection sensitivity and the accuracy of determining the propagation velocity and direction of arrival of the ionospheric disturbance by the grating of the receiving stations of the GLONASS / GPS satellite radio navigation systems, by restoring the spatial distribution of the total electronic content of the ionosphere according to atmospheric radio transillumination by GLONASS / GPS signals. To this end, the method is implemented by GLONASS / GPS satellite radio navigation systems and an extended array of dual-frequency receivers that provide reception and processing of signals.

Each two-frequency receiver contains a serially connected receiving path 1, a frequency converter 2, a QPSK demodulator 3, and a recording and analysis unit 4.

The receiving path 1 contains a receiving antenna 5 connected in series, an input feeder 6, a broadband filter — a preselector 7, a low-noise amplifier 8, and two bandpass filters 9.1 and 9.2.

The frequency converter 2 contains a mixer 11.1 (11.2) connected in series to the output of the bandpass filter 9.1 (9.2), the second input of which is connected to the output of the local oscillator 10.1 (10.2), and an intermediate frequency amplifier 12.1 (12.2).

The FMN demodulator contains in series with the output of the amplifier 12.1 (12.2) an intermediate frequency doubler 13.1 (13.2) phases, a divider 14.1 (14.2) phases in two, a narrow-band filter 15.1 (15.2) and a phase detector 16.1 (16.2), the second input of which is connected to the output amplifier 12.1 (12.2) of intermediate frequency, and the output is connected to block 4 registration and analysis.

Frequency converter 2 is constructed according to a superheterodyne circuit in which the same value of the intermediate frequency ω _CR1 (ω _CR2 ) is formed when signals are received at frequencies ω ₁ , ω _Z1 , ω ₂ and ω _Z2 , i.e.

_pr1 ω = ω ₁ -ω _{r1, pr1} ω = ω -ω _{r1 P1,}

_np2 ω = ω ₂ -ω _z2, ω _np2 = ω _z2 -ω _s2.

Therefore, if the tuning frequencies ω ₁ and ω _{2 are} taken as the main reception channels, then along with them there will also be mirror receiving channels, the frequencies ω _З1 and ω _{З2 of} which differ from the frequencies ω ₁ and ω ₂ by 2ω _pr1 , 2ω _pr2 and are located symmetrically (mirror) with respect to frequencies ω _g1 , ω _g2 local oscillators (Fig. 4). The conversion of the mirror channels of reception occurs with the same conversion coefficient k _PR as the main channels of reception. Therefore, they most significantly affect the selectivity and noise immunity of receivers.

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

where ω _ki , ω _kj are the frequencies of the i-th and j-th Raman reception channels; m, n, i, j are positive integers.

The most harmful combinational receiving channels are those generated by the interaction of the first harmonic of the signal frequency with the harmonic of the frequencies of small local oscillators (second, third, etc.), since the sensitivity of the receivers on these channels is close to the sensitivity of the receivers on the main channels. So, four combinational reception channels with m = 1 and n = 2 correspond to frequencies:

ω _k1 = 2ω _{g1 -ω pr1} , ω _k2 = 2ω _g1 + ω _pr1 ,

_k2 = 2ω ω _z2 -ω _np2, ω _{z2 k4} = 2ω + ω _np2,

where 2ω _g1 , 2ω _g2 are the second harmonics of the frequencies of the first and second local oscillators.

The presence of false signals (interference) received via mirror and Raman channels leads to a decrease in the selectivity and noise immunity of the receivers, to a decrease in the detection sensitivity and the accuracy of determining the propagation velocity and direction of arrival of the ionospheric disturbance recorded by the receivers.

The demodulator of 3 QPSK signals is constructed according to the Pistolkors Α scheme. Α., In which the reference voltage necessary for the operation of the phase detector 16.1 (16.2) is extracted directly from the received PSK signal using the reference voltage generating path, consisting of a phase doubler 13.1 (13.2) sequentially connected, a phase divider 14.1 (14.2) into two and a narrow-band filter 16.1 (16.2).

However, the phenomenon of “reverse operation” is inherent in this demodulator, which also leads to a decrease in the detection sensitivity and the accuracy of determining the propagation velocity and direction of arrival of the ionospheric disturbance recorded by the receivers.

An object of the invention is to increase the detection sensitivity and accuracy of determining the propagation velocity and direction of arrival of the ionospheric disturbance recorded by the two-frequency receivers of the GLONASS / GPS satellite radio navigation system by suppressing spurious signals (interference) received via additional channels and eliminating the “reverse operation” phenomenon.

The problem is solved in that the method of determining the propagation velocity and direction of arrival of the ionospheric disturbance, based in accordance with the closest analogue, on the analysis of data on the total electronic content in the Earth’s ionosphere, which are obtained as a result of processing signals received by two-frequency receivers of the GLONASS / GPS satellite navigation system, with the subsequent formation of time series of the full electronic content and their filtration in the range of oscillation periods corresponding to the ion response the spheres on the influence of the ionospheric excitation source, while using an extended receiving grating and sequentially testing the hypothesis about the values of the direction of arrival and the propagation velocity of the plane front of the ionospheric disturbance by forming the radiation pattern of the receiving grating and scanning it in a given sector of the space review "direction of arrival - velocity of propagation of the ionospheric disturbance »Due to the synthesis of the output signal of the receiving grating during the in-phase summation of the series of variations the electronic content of individual elements of the lattice with time shifts calculated on the basis of the verified values of the arrival direction and propagation velocity of the ionospheric disturbance and the distances traveled by the front of the ionospheric disturbance between the elements of the receiving lattice in the checked direction inside the spherical layer of the Earth’s ionosphere, the decision on the correctness of the hypothesis being tested and the detection of the ionospheric disturbances are accepted when the total signal exceeds a predetermined threshold level, the corresponding values The directions of the arrival direction and the phase velocity of propagation of the ionospheric disturbance are considered as estimated values, while to determine the total electronic content of the ionosphere, code measurements of pseudorange and phase measurements are taken together, group corrections associated with the multipath propagation of the signal and with vertical ionospheric and tropospheric delays are taken into account and the differential mode is used GLONASS / GPS satellite radio navigation systems, differs from the closest analogue in that о receive GLONASS / GPS signals at the carrier frequencies ω ₁ and ω ₂ , convert them in frequency using the frequencies ω _g1 and ω _{g2 of the} first second local oscillators, which are chosen equal to the carrier frequencies ω _g1 = ω ₁ and ω _g2 = ω ₂ , select low-frequency voltages proportional to the modulating codes M ₁ (t) and M ₂ (t), respectively, register and analyze them, and also multiply them with the voltages of the first and second local oscillators, previously phase shifted by 90 °, form control voltages, act on them at the control inputs 2 local oscillators and support vayut equality _r1 ω = ω ₁ and ω ₂ = ω _z2.

The geometry of determining the coordinates of a remote point source of ionospheric disturbance is shown in FIG. 1. An atmospheric radiolocation pattern is shown in FIG. 2. A block diagram of a classical two-frequency GLONASS / GPS signal receiver is shown in FIG. 3. Frequency diagrams illustrating the formation of additional receive channels are shown in FIG. 4. The block diagram of the proposed dual-frequency receiver of GLONASS / GPS signals is presented in FIG. 5.

To implement the proposed method, a GLONASS / GPS satellite radio navigation system is used, which consists of three parts: space, ground and user equipment.

The space part consists of 24 satellites orbiting in 6 orbits. The inclination of the orbits to the earth's equator is 55 degrees, the angle between the planes of the orbits is 60 degrees. The altitude of the orbits is 20180 km, the period of revolution is 12 hours. The power of the satellite transmitter is 50 W. GPS satellites are capable of moving, filling in gaps in the system if one of them is out of order. An important element of the satellite is the atomic clock, rubidium and cesium, four on each. Satellites are identified by a PRN (Pseudo Random Number), which is displayed on the GPS receiver.

Satellites are carefully monitored using the ground-based control segment - the control and tracking station. The latter's tasks include maintenance of the orbital system, determination of system time, pre-calculation of satellite orbit elements (ephemeris), modeling of the satellite’s clock behavior, transmission of satellite navigation data and its loading into the satellite’s memory.

As user equipment, two-frequency receivers of the GLONASS / GPS satellite radio navigation system are used.

и

специальный навигационный сигнал в виде бинарного фазоманипулированного сигнала. В сигнале зашифровываются два вида кода. Один из них код С/А - доступен широкому кругу потребителей. Он позволяет получать лишь приблизительную оценку местоположения, поэтому называется "грубым" кодом. Передача кода С/А осуществляется на частоте

и использованием фазовой манипуляции псевдослучайной последовательностью длиной 1023 символа. Защита от ошибок обеспечивается с помощью кода Гоулда. Период повторения С/А - кода - 1 мс, тактовая частота 1.023 МГц.All frequencies in the system are multiples of the fundamental frequency of the satellite clock, 10.23 MHz. Satellite transmits at two frequencies

and

special navigation signal in the form of a binary phase-shifted signal. Two types of code are encrypted in the signal. One of them is C / A code - available to a wide range of consumers. It allows you to get only a rough estimate of the location, so it is called a "rough" code. C / A code is transmitted at a frequency

and using phase manipulation with a pseudo-random sequence of 1023 characters in length. Error protection is provided using the Gould code. The repetition period of the C / A code is 1 ms, the clock frequency is 1.023 MHz.

с применением сверхдлинной псевдослучайной последовательности с периодом повторения 267 дней. Тактовая частота -10.23 МГц.Another code - Ρ provides a more accurate calculation of coordinates, but not everyone is able to use it, access to it is limited by the GPS service provider. This code is transmitted on frequency

using an extra-long pseudo-random sequence with a repetition period of 267 days. Clock frequency -10.23 MHz.

Radio transillumination of the atmosphere using the signals of satellite radio navigation systems and seven ground stations is an easily accessible and low-cost way to monitor its parameters in real time.

Transmission of the atmosphere with two-frequency GLONASS / GPS radio signals is based on the existence of the microwave dispersion phenomenon in the Earth’s atmosphere.

The total microphysical content along the line of sight from the phase center of the receiver antenna to the transmitter antenna is proportional to the difference in phase incursions at two frequencies. Considering that the phase velocity is equal in sign and opposite in magnitude to the group velocity, the microphysical content is proportional to the pseudorange difference determined from the navigation signals at two frequencies. However, for phase measurements, the microphysical content can only be determined accurate to a constant (within one session) constant. It is also worth noting that phase shift measurements are several orders of magnitude more accurate than pseudorange code measurements; therefore, it is advisable to use code and phase measurements together to determine the absolute microphysical content.

Multipath occurs as a result of secondary reflections of a satellite signal from large obstacles located in the immediate vicinity of the receiver. In this case, the phenomenon of interference arises and it is quite difficult to measure the distance, and the best way to deal with it is the rational placement of the receiver relative to obstacles. As a result of this factor, the errors in determining the pseudorange can increase by 2 m.

The ionosphere is an ionized atmospheric layer in the altitude range of 50-500 km, which contains free electrons. The presence of these electrons causes a delay in the propagation of the satellite signal, which is directly proportional to the electron concentration and inversely proportional to the square of the frequency of the radio signal.

To calculate the ionospheric correction, the measurement of pseudorange on the P-code at two frequencies is used:

Where

и

- частоты сигналов GPS.Where

and

- GPS signal frequencies.

и

соответственно.D _p1 , D _p2 - measurement of pseudorange on the P-code at frequencies

and

respectively.

The ionospheric correction of the pseudorange eliminates a systematic error of the order of 5 meters in determining the position vector of the observer at rest.

The troposphere is the lowest layer of the atmosphere (up to an altitude of 8-13 km). It also causes a delay in the propagation of the radio signal from the satellite. Signal delay in the troposphere is also caused by refraction effects. Unlike the ionospheric delay, the tropospheric delay does not depend on the signal frequency, it depends on meteorological parameters (pressure, temperature, humidity), as well as on the satellite height above the horizon. To calculate the tropospheric correction, measurements of pseudorange use measurements of temperature, air pressure, and partial pressure of water vapor. These measurements are available on the Internet for each base GPS station.

The ratio for calculating the tropospheric correction of the pseudorange of the ground observer has the form:

where T is the temperature in K;

P is the air pressure [mb];

In - partial pressure of water vapor [mb];

Θ - zenith angle of direction to the NCA.

Tropospheric delays cause 1 m pseudorange measurement errors.

The most effective means of eliminating errors is the differential method of observation. Its essence consists in performing measurements by two receivers: one is installed at a defined point, and the other at a point with known coordinates - the base (control) station. In differential mode, it is not the absolute coordinates of the first receiver that are measured, but its position relative to the base (base vector). Using the differential mode allows you to bring the accuracy of code measurements to tens of centimeters, and phase - to units of millimeters.

The determination of the value of the total electronic content (TEC) of the ionosphere is carried out by two-frequency measurements of the distance between the navigation satellite and the ground receiver

λ₁, λ₂ - частоты и длины волн навигационных сигналов:Where

λ ₁ , λ ₂ - frequency and wavelength of navigation signals:

L ₁ , λ ₁ , L ₂ , λ ₂ is the phase path of the transionospheric radio signals (L ₁ , L ₂ is the number of full rotations of the phase);

Θ - zenith angle of the beam "receiver - navigation satellite".

The set of receiver-navigation satellite beams in a given region forms a receiving array, each i-th element of which at time t is characterized by a change in the TEC value Y _i (t) and the position of the corresponding ionospheric point X _i (t) Y _i (t) and Z _i (t). The time series of TECs reflect both regular changes in TECs at the registration point and variations in TECs caused by ionospheric disturbances of a different nature.

To distinguish characteristic ionospheric disturbances, the TEC series undergo a special filtering procedure in the range of periods corresponding to the scale of the disturbance.

The detection and determination of the spatio-temporal parameters of the ionospheric disturbance is carried out by sequentially testing hypotheses about the values of the direction of arrival and propagation velocity of the ionospheric disturbance.

For each pair of checked values (α, v), the radiation pattern of the receiver array is formed and is accordingly oriented in the phase space [α, v] due to the in-phase summation of the individual rows ΔY _i (t) of the receiver array to a certain neutral row ΔY ₀ (t), selected as a reference, with time shifts τ and the formation of the output signal of the receiving array:

where p is the number of elements of the receiving grid.

The time shift τ _i is defined as the difference between the time t _{j of the} j-th count of the i-th total number of TEC and the time t _{0 of} recording the ionospheric disturbance by the central element of the receiving array τ _i = t _j -t ₀ and is selected based on minimizing the expression describing the dynamics of propagation of the disturbance :

where Δp _i is the distance traveled by the wave front between the ith and the central element of the receiving array.

For extended receiving gratings, the distance is calculated taking into account the curvature of the Earth. To this end, in a given direction α of the arrival of the ionospheric disturbance wave at a height h _max, a remote point source (indicated by point E in Fig. 1) is set, which will be the pole of the orthodromic coordinate system whose equator (strong bold line in Fig. 1) passes through the central element of the receiving grate (point A in Fig. 1). Then the wave front propagating from a remote point source and arriving through the ith element of the receiving array (point B in Fig. 1) will be a latitudinal circle (a thick broken line) parallel to the equator of the resulting orthodromic system. Such a model corresponds to a plane wave of ionospheric disturbance propagating over the Earth's sphere.

The geocentric coordinates (X _e , Y _e , Z _e ) of a remote source of ionospheric disturbance are determined using the rules of spherical trigonometry. In this case, we consider a spherical triangle, the vertex A of which is the central element of the receiving grating with known coordinates (X ₀ , Y ₀ , Z ₀ ). The vertex C of this triangle is the north pole of the geocentric coordinate system (0, 0, R + h _max ), where R is the radius of the Earth. It is necessary to determine the coordinates of the third vertex E, which will be the remote source. So that the remote source E is the pole of the orthodromic coordinate system, the angular size of the side AE of the spherical triangle is set to π / 2. In the obtained spherical triangle, two sides AC and AE are known, as well as the angle between them <LCAE = α, which is a typical problem for solving a spherical triangle. Using the cosine theorem of the sides of a spherical triangle, the third side and the coordinates (X _e , Y _e , Z _e ) of the remote source E.

The distance traveled by the wave front between the ith and the central element of the receiving array is determined as the difference between the distances AE and BE (Fig. 1) and is written in the form:

where (X _i , Y _i , Z _i ) are the coordinates of the i-th element of the receiver array at time t _j .

The decision on the correctness of the tested hypothesis is made when the total signal exceeds a predetermined threshold level. In this case, it is believed that an ionospheric disturbance is detected, and the corresponding values of α and V, for which the total signal of the receiving grating exceeded the threshold value, are considered as estimates of the direction of arrival and the phase propagation velocity of the detected ionospheric disturbance.

Each proposed dual-frequency receiver operates as follows.

The input of the receiving antenna 5 simultaneously receives signals from the spacecraft of two satellite radio navigation systems GLONASS and GPS:

where U ₁ , U ₂ , ω ₁ , ω ₂ , ϕ ₁ , ϕ ₂ , T ₁ , T ₂ are the amplitudes, carrier frequencies and durations of GLONASS / GPS signals:

- доплеровские смещения частоты:

- Doppler frequency shifts:

- манипулируемые составляющие фазы, отображающие законы фазовой манипуляции в соответствии с модулирующими кодами M₁(t) и M₂(t) соответственно, причем ϕ_к1(t)=const и ϕ_к2(t)=const при kτ_э<t<(k+1)τ_э и могут изменяться скачком при t=kτ_э, т.е. на границах между элементарными посылками (k=1,2,…, N-1);

- manipulated phase components that display the laws of phase manipulation in accordance with the modulating codes M ₁ (t) and M ₂ (t), respectively, with ϕ _k1 (t) = const and ϕ _k2 (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 a signal of duration T ₁ (T ₁ = N ₁ ⋅ τ _e ) and T ₂ (T ₂ = N ₂ ⋅ τ _e ).

The frequency response of the receiving path 1 is determined by the frequency spectrum of the received signals. The spectrum of signals of the navigation spacecraft (NSC) of the GPS system when working with the C / A code is (1574, 42-1594.24) MHz, the spectrum of the signals of the GLONASS system with the C / A code is (1602-1620) MHz .

This means that the total frequency band of the received signals is equal to 1574.24≤Δω≤1620 MHz, that is, the occupied frequency band is 50 MHz.

Received PSK signals from antenna 5 enter the input feeder 6, which is a quarter-wave segment of a coaxial line closed on one side and serves to coordinate the parameters of the antenna and the input circuits of the receiver. From the output of the feeder 5 QPSK signals are fed to the input of a broadband filter preselector 7, which serves to limit the frequency band of the received signals in the range of 1574.42-1621 MHz. The specified filter, made on microwave lines, implements a 5th order elliptical Cower bandpass filter. The broadband filter preselector 7 has an important advantage, namely, an almost linear phase response in the passband of the filter, which is a great advantage when working with complex phase-shift keyed signals transmitted from satellites. This leads, for example, to the fact that the filter preselector 7 has the same linear group delay time τ in the passband equal to about 2.5 ns. Such an implementation leads to the fact that there is no need to use a calibrator to ensure the same group delay time τ for all signals received from the satellite.

From the output of the filter preselector, the signals are fed to the input of a low-noise amplifier 8, which provides the main gain of the receiving path 1 and is based on gallium arsenide transistors with a Schottky barrier.

Bandpass filters 9.1 and 9.2 distinguish the PSK signals u ₁ (t) and u ₂ (t), which are fed to the first inputs of the mixers 11.1 and 11.2, the second inputs of which are supplied with the local oscillator voltages 10.1 and 10.2, respectively.

u _g1 (t) -U _g1 ⋅cos (ω _g1 t + ϕ _g1 )

u _z2 (t) = U _r2 ⋅cos (ω t + φ _{r2 r2)}

At the output of the mixers 11.1 and 11.2, voltages of combination frequencies are generated. Since the frequencies ω _g1 and ω _{g2 of the} local oscillators 10.1 and 10.2 are chosen equal to the frequencies of the received signals (ω _g1 = ω ₁ and ω _g2 = ω ₂ ), low-frequency voltages (zero-frequency voltages) are allocated by low-pass filters 12.1 and 12.2:

u _н1 (t) = U _н1 ⋅cosϕ _k1 (t),

u _n2 (t) = U _n2 ⋅cosϕ _k2 (t),

Where

proportional to the modulating codes M ₁ (t) and M ₂ (t), respectively. These voltages are fed to the inputs of block 4 registration and analysis.

It should be noted that the choice of frequencies ω _g1 and ω _{g2 of} local oscillators 10.1 and 10.2, equal to the frequency ω ₁ and ω _{2 of the} received PSK signals (ω _g1 = ω ₁ and ω _g2 = ω ₂ ), provides a combination of two procedures:

the conversion of the received PSK signals to zero frequencies and the allocation of low-frequency voltages u _н1 (t) and u _н2 (t) proportional to the modulating codes M ₁ (t) and M ₂ (t), i.e. synchronous detection of received PSK signals using a mixer 11.1 (11.2), a local oscillator 10.1 (10.2) and a low-pass filter 12.1 (12.2). Such circuit designs can get rid of additional receiving channels (mirror channels at frequencies ω _z1 , ω _z2 , combination channels at frequencies ω _k1 , ω _k2 , ω _k3 and ω _k4 ) ·

Since the frequencies ω ₁ and ω _{2 of the} received FMN can change under the influence of various destabilizing factors, including the Doppler effect, then to fulfill and maintain the equality ω _g1 = ω ₁ and ω _g2 = ω ₂ , the PLL 16.1 is used (16.2), consisting of a multiplier 14.1 (14.2), a phase shifter 13.1 (13.2) by 90 ° and a phase detector 15.1 (15.2).

Thus, the proposed method compared to the prototype and other technical solutions of a similar purpose provides an increase in the detection sensitivity and the accuracy of determining the propagation velocity and direction of arrival of the ionospheric disturbance recorded by the two-frequency receivers of the GLONASS / GPS satellite radio navigation system. This is achieved by suppressing false signals (interference) received via additional channels and eliminating the phenomenon of “reverse operation”.

Technical implementation of these procedures is provided by local oscillators, mixers, low-pass filters and FAPU systems. Moreover, these circuit designs simultaneously serve as frequency converters and synchronous demodulators of received PSK signals, free of additional reception channels and the phenomenon of “reverse operation”, are simple, novel, original and can be widely used.

Claims (1)

A method for determining the propagation velocity and direction of arrival of the ionospheric disturbance, based on the analysis of data on the total electronic content in the Earth’s ionosphere, which are obtained as a result of processing signals received by two-frequency receivers of the GLONASS / GPS satellite navigation system, followed by the formation of time series of the full electronic content and their filtering in the range of oscillation periods corresponding to the response of the ionosphere to the action of a source of ionospheric disturbance, using cosiness is an extended receiving antenna and the hypothesis about the values of the direction of arrival and the propagation velocity of the plane front of the ionospheric disturbance is checked by forming the radiation pattern of the receiving array and scanning it in a given sector of the space overview "arrival direction - propagation velocity of the ionospheric disturbance" due to the synthesis of the output signal of the receiving array at in-phase summation of series of variations in the total electronic content of individual lattice elements with time shift calculated on the basis of the verified values of the direction of the ionospheric perturbation and the distances traveled by the front of the ionospheric perturbation between the elements of the receiving lattice in the checked direction inside the spherical layer of the Earth’s ionosphere, the decision about the correctness of the hypothesis being tested and the detection of the ionospheric perturbation is made when the total signal exceeds a predetermined threshold level, the corresponding values the directions of arrival and the phase velocity of propagation of the ionospheric disturbance are considered In order to determine the total electronic content of the ionosphere, they carry out joint code measurements by encoding two-frequency signals transmitted by the GLONASS / GPS satellite radio navigation system and received by their two-frequency receivers of the GLONASS / GPS satellite radio navigation system, and phase measurements take into account group corrections associated with multipath propagation signal with vertical ionospheric and tropospheric delays and use the differential mode of satellite radios GLONASS / GPS navigation systems through two receivers, one of which has known coordinates, characterized in that they receive GLONASS / GPS signals at carrier frequencies ω ₁ and ω ₂ , convert them in frequency using frequencies ω _g1 and ω _{g2 of the} first and second local oscillators which are chosen equal to the carrier frequencies ω _g1 = ω ₁ and ω _g2 = ω ₂ , low-frequency voltages are proportional to the modulating codes M ₁ (t) and M ₂ (t), respectively, they are recorded and analyzed, and they are also multiplied with the voltages of the first and second local oscillators, precedes flax shifted in phase by 90 °, form the control voltages, to affect their control inputs of the oscillators and maintained equality _r1 ω = ω ₁ and ω ₂ = ω _z2.

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