Method of determining distance between spacecraft and stations

FIELD: physics.

SUBSTANCE: method involves reception, emission and relay of a primary and terminal radio signals between a spacecraft, primary station and an alternate station. An additional primary radio signal and an additional terminal radio signal is further relayed from the spacecraft to the primary station where these signals are received. Distance between the spacecraft, primary and alternate stations is determined from the time interval between emission of the signal and reception of the primary and additional primary signals and reception of terminal, auxiliary terminal, additional terminal and auxiliary additional terminal radio signals at the primary station taking into account Doppler frequency shift.

EFFECT: more accurate determination of distance between spacecraft and stations.

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The present invention relates to the field of space navigation and geodesy, and more specifically to methods for measuring distances between spacecraft and stations.

The present invention can be used for navigation bind with high accuracy (taking into account the influence of the Earth's ionosphere on the measurement of the spacecraft relative to the tracking stations, which can be stationary, mobile, terrestrial, space, etc.

In addition, the present invention with the greatest success can be used to determine with high accuracy the location of the above-mentioned stations, including, as mentioned, ground stations, and the remote detection of parameters of the ionosphere in the areas of their location.

Also, the present invention can be used in systems for monitoring parameters of the Earth's ionosphere, including for later use in data systems global positioning objects (GPS, Gallileo, GLONASS and other), with the aim of taking into account the parameters of the ionosphere and increasing, thereby, the positioning accuracy of the defined objects.

Currently, much attention is paid to solving problems of geodesy and Geophysics, as, for example, the forecasting of earthquakes, the definition of "progress" lithospheric plates of the Earth, determining parameterfree rotation and so on. In this regard, the increasing application finds space technology, in particular spacecraft, used to locate stations at the current point in time by determining the distances from the stations to these satellites. While there are high requirements for limiting the time of determining the distance between the spacecraft and stations and to increase the accuracy of measurement of these distances, in particular by taking into account the influence of the ionosphere on the measurement results.

Prior art

The known method of determining the distance between the spacecraft and stations (patent RF №2323860), including the primary radiation of the radio signal from the base station in the direction of the spacecraft, the reception of the primary signal on the spacecraft, the primary relay the radio signal from the spacecraft in the direction of the main station, the reception of the primary signal at the base station, the measurement of the moments of emission and reception, respectively, of the primary signals at the base station, the radio communication end signal of the spacecraft with at least one additional station by relaying the primary radio signal from the spacecraft to a secondary station, the reception of the primary signal on the additional the first station, convert it to the target radio signal by the relay in the direction of the spacecraft and the reception of the end signal on the spacecraft, retransmission destination radio signal from the spacecraft in the direction of the main station and its reception at the base station, the measurement of the moment of reception of the end signal at the base station, the measurement of Doppler shifts of the carrier frequencies of the radio signals received at the base station, the measurement of time intervals, which are judged on the distance between the spacecraft and the primary and secondary stations.

In this method for obtaining high accuracy of determining the distance between the spacecraft and stations by considering the influence of the ionosphere may use mathematical models that assessed the changes that the group and phase velocities of propagation of radio signals in the ionosphere at locations of stations meteo data and ionospheric data obtained by independent methods (see, for example: ICD-GPS-200, Revision C, U.S.Government, October 10, 1993, p.120-125; http://www.navcen.uscg.gov/gps/geninfo/IS-GPS-200D.pdf).

This limits the accuracy of determining the distance between the spacecraft and stations and requires additional time to obtain these data and their processing.

In addition, in this method, an additional is the ability to remotely determine in real-time delays of radio signals in the ionosphere and the integral of electron density TES when determining distances between the spacecraft, the primary and secondary stations.

Brief description of the invention

The aim of the present invention is to develop a method of determining the distance between the spacecraft and stations, allowing to reduce the errors associated with the influence of the ionosphere on the results of determining the distances between the spacecraft and stations, that is, improving the accuracy of determining the distance between the spacecraft and stations.

In addition, the present invention is the provision of remote data acquisition about the ionosphere and the integral of electron density TES in the areas of the stations when determining distances between the spacecraft, the primary and secondary stations.

This is accomplished by the fact that extra primary relay the radio signal from the spacecraft in the form of at least one additional primary signal in the direction of the main station, take additional primary signal at the base station and measure the time of reception of this signal, the primary relay the radio signal from the spacecraft in the direction of additional stations in the form of at least one additional primary signal, take it to a secondary station and a relay in the form of fill in the preliminary final signal in the direction of the spacecraft, take it on the spacecraft and relay it with the spacecraft in the form of at least one additional target signal in the direction of the main station, take the target signal and additional target signal on the spacecraft and relay them to the form, respectively, an auxiliary end and/or additional auxiliary end signal in the direction of the main station, take these radio signals at the base station and measure the moments of reception of these signals, and the time intervals for which additional judge the distance between the spacecraft, the primary and secondary stations measure the time intervals between the moment of emission of the primary the radio signal from a base station, the moments of reception at the base station of the primary and additional primary signal and the moments of reception at the base station of the destination radio, additional end radio, auxiliary end signal and/or additional auxiliary end signal.

Tasks that should be solved by the inventions

The basis of the invention was based on the task of developing a method of determining the distance between the spacecraft and stations having such stage is leitlinie operations radio communication between a spacecraft and an additional station would be carried out by such signals, and the measurement of time intervals, which are judged on the distance between the spacecraft and the primary and secondary stations, would be carried out between these points is that the measurement of time intervals between the moments of the radiation of radio signals with the base station and reception of radio signals at the base station would take into account the effect of the ionosphere on the results of determining distances and would correspond to the location of the spacecraft in the same point of the orbit.

Method of solving problems

This is achieved by a method for determining the distance between the spacecraft and stations, including the primary radiation of the radio signal from the base station in the direction of the spacecraft, the reception of the primary signal on the spacecraft, the primary relay the radio signal from the spacecraft in the direction of the main station, the reception of the primary signal at the base station, the measurement of the moments of emission and reception, respectively, of the primary signals at the base station, the implementation of the radio communication end signal of the spacecraft with at least one additional station by relaying the primary radio signal from space so is the additional station, the reception of the primary signal on the docking station, its conversion into the final signal by the relay in the direction of the spacecraft and the reception of the end signal on the spacecraft, retransmission destination radio signal from the spacecraft in the direction of the main station and its reception at the base station, the measurement of the moment of reception of the end signal at the base station, the measurement of Doppler shifts of the carrier frequencies of the radio signals received at the base station, the measurement of time intervals, which are judged on the distance between the spacecraft and the primary and secondary stations,

advanced primary relay the radio signal from the spacecraft in the form of at least one additional primary signal in the direction of the main station, take additional primary signal at the base station and measure the time of reception of this signal, the primary relay the radio signal from the spacecraft in the direction of additional stations in the form of at least one additional primary signal, take it to a secondary station and a relay in the form of additional target signal in the direction of the spacecraft, take it on the spacecraft and relay it with KOs is practical apparatus in the form, at least one additional target signal in the direction of the main station, take the target signal and additional target signal on the spacecraft and relay them to the form, respectively, an auxiliary end and/or additional auxiliary end signal in the direction of the main station, take these radio signals at the base station and measure the moments of reception of these signals, and the time intervals for which additional judge the distance between the spacecraft, the primary and secondary stations measure the time intervals between the moment of emission of the primary radio signal from a base station, the moments of reception at the base station of the primary and secondary primary radio and moments of reception at the base station of the destination radio, additional end radio, auxiliary end signal and/or additional auxiliary end signal.

In addition, when receiving a primary, final, additional end of radio signals on the spacecraft and relay these signals from the satellite in the form of primary and secondary primary signals, end, additional finite auxiliary end and VSP is additional service end signals coherent conversion of radio signals when the relay is executed under the following conditions:

;

where- conversion of the carrier frequency of the radio signal when it is coherent relay on the spacecraft in the form of initial, final and additional end signals;

- conversion of the carrier frequency of the radio signal when it is coherent relay on the spacecraft in the form of additional primary, auxiliary end and supporting the additional end of the radio.

It is advisable that as the time intervals for which additional judge the distance between the spacecraft in each of its locations in orbit and additional station, measured the intervals between the moments of emission and reception of the primary signal, the moments of the radiation of the primary signal and receive additional primary signal and the moments of reception of the primary and additional primary signal at the base station, and the distance (l1between the satellite and main station is judged by value:

where C is the speed of radio wave propagation;

t11- the moment of reception of the primary signal at the base station;

t12- the additional the first is knogo signal at the base station;

t0the moment of radiation of the primary signal from the primary station.

It is desirable that the target signal, which was adopted on the spacecraft, retransmitted in the form of a finite and an auxiliary target signals in the direction of the main station, an additional final signal, which was adopted on the spacecraft, retransmitted in the form of additional target and auxiliary additional target signals in the direction of the main station, and the time intervals for which additional judge the distance between the spacecraft in each of its locations in orbit and additional stations, measured by the interval between the sum of the moments of reception of the primary and additional primary signal and accordingly the sum of the moments of the reception end and the auxiliary end of the radio signals and the sum of the moments receive an extra end and supporting additional target signals at the base station, and the distance (l2between a spacecraft and an additional station to be judged by the ratio:

where: N1and t211accordingly Doppler shift of the carrier frequency and the time of reception of the end signal, received at the base station;

N2and t212accordingly, the Doppler shift of the carrier frequency and the time of reception of the auxiliary end signal, received at the base station;

N3and t221accordingly Doppler shift of the carrier frequency and the time of reception of the additional end of the radio signal received at the base station;

N4and t222accordingly Doppler shift of the carrier frequency and the time of reception of the additional auxiliary end signal is received at the base station;

t11- the moment of reception of the primary signal, received at the base station;

t12- the date of the receipt of additional primary radio signal received at the base station.

It is reasonable that these Doppler shifts (N1N2N3N4) carrier frequency end of the radio signals was determined from the formula:

N1=(m1f0-f1-211)/(2m1f0);

N2=(m2f0-f2-212)/(2m2f0);

N3=(m1f0-f1-221)/(2m1f0);

N4=(m2f0-f2-222)/(2m2f0); where:

m1- conversion of the carrier frequency of the radio signal when it is coherent relay on the spacecraft in the form of initial, final and additional end signals;

m2- conversion of the carrier frequency of the radio signal when it is coherent relaying on to the economic apparatus in the form of additional primary, auxiliary end and supporting additional target radio signal;

f0the primary carrier frequency of the radio signal radiated from the primary station;

f1-211- carrier frequency end of the radio signal received at the base station;

f1-212- carrier frequency of the auxiliary end of the radio signal received at the base station;

f1-221- carrier frequency additional target radio signal received at the base station;

f2-222- carrier frequency auxiliary additional target radio signal received at the base station.

In addition, in the case of many additional stations the measurement of time intervals between the moment of emission of the primary radio signal from a base station, the moments of reception at the base station of the primary and additional primary signal and the moments of reception at the base station of the destination radio, additional end radio, auxiliary end signal and/or additional auxiliary end signal, which is judged on the distance between the spacecraft and each of the many additional stations carry the same primary signal radiated from the primary station.

Brief description of drawings

Other CE and and advantages of the present invention will be shown below when considering the description of examples of embodiment with reference to the accompanying drawings, on which:

Figure 1 depicts the block diagram of the known geodetic system that implements a patent-pending method of determining the distance between the spacecraft and stations;

Figure 2 schematically depicts the temporal sequence of transmission and reception of radio signals at the stations and the spacecraft when implementing a patentable method of determining the distance between the spacecraft and stations.

Detailed description of the invention

The method is implemented on a known geodetic system (Patent RF №2323860).

Known geodetic system contains the base 1 (Fig 1) and an additional 2 stations, each of which has respectively the antenna 3, 4. Orbit 5, conventionally shown by the dotted line shows the movement of the spacecraft 6 with the antenna 7, through her point 8 (1), 9 (C2) and 10 (C3). In figure 1 is also provided conditionally designated radio signals: a first signal 11, radiated from the base station 1, located at point a in the direction of the spacecraft 6, the primary signal 12, relayed from the spacecraft 6 in the direction of the main station 1, additional primary signal 13, relayed from the spacecraft 6 in the direction of the main station 1, the primary signal 14, relayed from the spacecraft 6 on the managing additional station 2, and additional primary signal 15, relayed from the spacecraft 6 in the direction of additional station 2, the end signal 16, relayed from the docking station 2 in the direction of the spacecraft 6, additional end signal 17, relayed from the docking station 2 in the direction of the spacecraft 6, the end signal 18, relayed from the spacecraft 6 in the direction of the main station 1, the auxiliary end signal 19, relayed from the spacecraft 6 in the direction of the main station 1, additional target signal 20, relayed from the spacecraft 6 in the direction of the main station 1 and support additional end signal 21, relayed from the spacecraft 6 in the direction of the main station 1.

Primary radio signals 11, 12, 14 defined when the spacecraft 6 point 8 (B1) orbit 5. Additional primary signals 13, 15 are defined when the spacecraft 6 point 8 (1) orbit 5.

The final radio signals 16, 18 and auxiliary end signal 19 are defined, respectively, when the spacecraft 6 point 9 (C2) orbit 5 and additional station 2 at point D.

Additional the target radio signal 17, 20 and support additional end signal 21 are defined, respectively, when the spacecraft 6 point 10 (3) orbit 5 and additional station 2 at point D.

Figure 2 schematically shows the timing sequence of transmission and reception of radio signals at the stations and the spacecraft when implementing a patentable method of determining the distance between the spacecraft and stations. The numbering of these signals corresponds to the numbering of the signals displayed in figure 1.

Schematically shown in figure 2: h1- conditional height at which begins to show the influence of the ionosphere in the area of the base station 1; h2- conditional height at which begins to show the influence of the ionosphere in the area of the docking station 2; r is a conditional thickness of the layer of the ionosphere.

The method is implemented as follows.

At the base station 1 (a) form and radiate from an antenna 3 in the direction of the orbiting 5 spacecraft 6 primary signal 11 with the carrier frequency f0. This signal 11 receive antenna 7 spacecraft 6, located at the point 8 (B1) orbit 5, and coherently (i.e. preserving phase relationships and conversion factor m1) relay in the direction of core 1 and an additional 2 stations according to the respectively the primary signal 12 and the primary signal 14. In addition, the signal 10 receive antenna 7 spacecraft 6, located at the point 8 (B1) orbit 5, and coherently (with a conversion factor of m2) relay in the direction of core 1 and an additional 2 stations respectively additional primary signals 13 and 15. Additional station 2 is located at the point D. Then take the primary signal 12 and additional primary signal 13 at the base station 1. Take the primary radio antenna 14 4 additional station 2, located at the point D, coherently convert it (with a conversion factor of 1/m1in the final signal 16 relay in the direction of the spacecraft 6 and accept the end signal 16 on the spacecraft 6, which during this time will be moved from point 8 (B1in point 9 (C2) orbit 5. Take additional primary signal antenna 15 4 additional station 2, located at the point D, coherently convert it (with a conversion factor of 1/m2in the end the radio signal 17 relay in the direction of the spacecraft 6 and take an additional final signal 17 on the spacecraft 6, which during this time will be moved from point 8 (1in point 10 (3) orbit 5.

Measure the time t0(2) radiation pervi the nogo signal 11 with the base station 1, time t11receiving a primary signal 12 at the base station 1, t12receiving additional primary signal 13 at the base station 1 and measure the intervals (t11-t0) and (t12-t0time, defined respectively by the points t0, t11and t12. Then on the measured time intervals (t11-t0) and (t12-t0determine the length l1between spacecraft 6, located at the point 8 (B1) orbit 5, and base station 1 from the following equation:

where C is the speed of propagation of radio waves.

Distance 11between spacecraft 6, located at the point 8 (B1) orbit 5, and the main station 1 corresponds to time T=tb1=[(t11+t0)/4+(t12+t0)/4].

To determine the range 12between spacecraft 6 and additional station 2 relay final signal 16 in the form of the final signal 18 (conversion factor m1and auxiliary end signal 19 (conversion factor m2with spacecraft 6, located at the point 9 (C2) orbit 5, in the direction of the main station 1. Relay additional end signal 17 in the form of additional end radish is Ala 20 (with a conversion factor of m 1) and additional auxiliary end signal 21 (conversion factor m2with spacecraft 6, located at the point 10 (3) orbit 5, in the direction of the main station 1. In the General case, the carrier frequency of all signals (except emitted from the base station radio 10, have a Doppler frequency shifts caused by the movement of the spacecraft 6 relative to stations 1 and 2.

Accept the end signal 18 and the auxiliary end signal 19 at the base station 1 and measure, respectively, the moments of t211and t212reception of these signals. Take an additional final signal 20 and the auxiliary additional end signal 21 at the base station 1 and measure, respectively, the moments of t221and t222reception of these signals. Then measure the time intervals: [(t211+t212)-(t12+t11)] and [(t221+t222)-(t12+t11)]. In addition, determine Doppler shifts (N1N2N3N4frequencies of the carrier signals from the formula:

N1=(m1f0-f1-211)/(2m1f0);

N2=(m2f0-f2-212)/(2m2f0);

N3=(m1f0-f1-221)/(2m1f0);

N4=(m2f0-f2-222)/(2m2f 0); where:

where- conversion of the carrier frequency of the radio signal when it is coherent relay on the spacecraft in the form of initial, final and additional end signals;

- conversion of the carrier frequency of the radio signal when it is coherent relay on the spacecraft in the form of additional primary, auxiliary end and supporting the additional end of the radio.

f0the primary carrier frequency of the radio signal radiated from the primary station;

f1-211- carrier frequency end of the radio signal received at the base station;

f1-212- carrier frequency of the auxiliary end of the radio signal received at the base station;

f1-221- carrier frequency additional target radio signal received at the base station;

f2-222- carrier frequency auxiliary additional target radio signal received at the base station;

choose the conversion factors m1and m2satisfying the following condition:

Finally, the distance (l2) between the spacecraft and the additional station is judged by value:

On the experimental values of the distances l 1and l2consistent with the finding of the spacecraft 6 point 8 (1) orbit 5, that is, the time T of reception of the primary signal 10 on the spacecraft 6, which is determined from the relationship:

T=[t0+(t1+t0)/4+(t12+t0)/4] when performing the above selection criteria conversion factors m1and m2.

Let us consider the ratio illustrating the implementation of the proposed method. For simplicity, consider the "dual" version of the method, then there is an option when the relay on the spacecraft one additional primary signal, one additional target signal and one additional auxiliary target radio signal. If on the spacecraft transmit two radio signal in the above set, it will be implemented "trehkostochny" variant of the proposed method.

The time interval passage signal 10 (figure 1 and figure 2) from station 1 (a) to spacecraft 6 (point B1) can be expressed as:

C is the speed of radio wave propagation;

τion1f0- additional delay signal 10 with the carrier frequency f0when passing through the ionosphere; τtrop1the delay in passing the signal in the troposphere; τapp1- delay apparatus is e; τerr1delays due to other factors.

For radio signals 11 and 12 can be written:

where τion1f1- additional delay signal 11 with the carrier frequency f1when passing through the ionosphere; τion1f2- additional delay signal 12 with the carrier frequency f2when passing through the ionosphere; τapp2τapp3- delays in the equipment.

Some components of equations (1), (2) and (3) can be identified and accounted for by the known methods:

τtrop1- meteo data modeling, τapp1τapp2τapp3- calibrations τerr1τerr2τerr3- taking into account relativistic and other effects, approximation and so on (see, for example, "Bernese GPS Software Version 5.0" Edited by Rolf Dach, Urs Hugentobler, Pierre Fridez, Michael Meindl, January 2007, Astronomical Institute, University of Bern).

For clarity and simplicity, the further consideration of temporarily assuming the above factors are known or can be determined at the first stage they are not taken into account when determining distances between the spacecraft and stations.

When implementing the proposed method, the original values of the measured points in time of the reception of radio signals at the base station and time intervals will be adjusted based on the known values of the above components./p>

Consider into account the ionospheric delay in the determination of the distances between spacecraft 6 and stations 1 and 2.

From equations (1), (2) and (3) we obtain:

It is known (for example [2])that the value of group and phase delay τionsignals due to the influence of the ionosphere, their value is directly linked to the integrated electron concentration (TEC) in the ionosphere along the path of the signals in the ionosphere (see, e.g., "Modeling The Ionosphere With Prare" Frank Flechtner, Bedrich Stefan, Andreas Teubel, GeoForschungsZentrum Potsdam, Germanyhttp://adsc.gfz-potsdam.de/prare/papers/ Florenz97/IonCalVal /florenz_ioncalval.htm1; "Determination of the ionospheric error in the pseudorange measurement of single frequency equipment systems GLONASS And GPS Moukarzel, Ullathai, Krasnoyarsk state technical University, 15 December 2002; http://jre.cplire.ru/jre/dec02/6/text.html):

where f is the carrier frequency [Hz] signal, C is the speed of light [m/s] and Ne - electron density [e/m3]. The sign of the correction is positive for signal range (group velocity <C) and, respectively, negative for Doppler measurements (phase velocity >); the ten - integrated electron concentration along the path S of the signal in the ionosphere [electrons/m2]; 1016electron/m2 defined as 1 unit TEC - (TECU).

Then (6) can be expressed as follows:

For exceptions in equation (8) delays associated with the ionosphere, we impose the condition:

i.e.

or

where- conversion of the carrier frequency of the radio signal when it is coherent relay on the spacecraft in the form of initial, final and additional end signals;

- conversion of the carrier frequency of the radio signal when it is coherent relay on the spacecraft in the form of additional primary, auxiliary end and supporting the additional end of the radio.

In other words, the carrier frequency of the radio signal, which is converted to the original carrier frequency of the received radio signal is chosen so that the sum of the delay time of passage in the ionosphere radio signal with a nominal frequency f1and f2was equal to the delay time of passage in the ionosphere signal at frequency f0for the same route. While the actual values of the carrier frequencies f0f1and f2may differ from the nominal due to the Doppler add the GOV, but these differences are so little effect on the signal delay in the ionosphere that they can be neglected.

When running (9) equation (8) can be converted as:

2tb1=[2t0+t11+t12]/2, or

Equation (10) determines the time tb1reception and retransmission of the signal 10 on the spacecraft 6. When choosing parameters for coherent conversion of the signals to the spacecraft 6 in accordance with equation (9) the definition of this time will not depend on the values of the electron concentration electron TES.

Further, by defining tb1and knowing the measured values of t0, t11and t12you can determine the values of the integral e concentration (TEC1along the path of radio signals in the ionosphere along AB1:

Determine the value of the group delay τion1f0radio 10 with carrier frequency f0on the track AB1due to the influence of the ionosphere.

Finally, the distance l1(AB1from main station 1 to spacecraft 6 (corresponding to time tb1reception and retransmission of the signal 10 on the spacecraft 6 point 8 (B1)) determined by the equation:

where - storestrandstraede radio waves;

t0the moment of radiation of the primary signal 11 with the base station;

t11- the moment of reception of the primary signal 12 at the base station 1;

t12- the date of the receipt of additional primary signal 13 at the base station 1.

Consider the passage of signals along the B1D2. The signal 10 is received and coherently is relayed to the spacecraft 6 and in the form of radio signals 13 and 14. their take on additional station 2, which, at the time of reception is at point D.

where Vdb- the rate of change of the distance between a spacecraft and an additional station 2.

Given that the error in the measurement range due to the delay of radio signals in the ionosphere may amount to about 100 meters, it can be shown that:

meters.

Due to the smallness of this difference (B3D-B2D) for simplicity, upon further consideration, it can be neglected (that does not prevent, if necessary, subsequently to consider this value in the final calculations) and we can assume that

B3D=B2D and then (17) is reduced to;

For radio(17), (18), (19), (20) fair following the respective ratios:

As mentioned above, then consider known and does not take into account the components τtropiτappiand τerri.

Consider the difference between expressions (19) and (21) taking into account (14) and (15):

Taking into account expressions (7), we can determine the value of the integral e concentration (TEC21along the path of radio signals in the ionosphere along the B1D:

Similarly, consider the difference between expressions (20) and (22) subject to (14) and (15):

Taking into account expression (7) from equation (25), we can determine the value of the integral of the electron concentration (TEC22along the path of radio signals in the ionosphere along the B1D:

Let us further consider the difference between expressions (19) and (20):

and

and the difference between the expressions (21) and (22):

t221-t222ion4f1ion4f2

and

Determine the value of the group delay τion4f0radio signals 18, 19, converted to carrier frequency f0on the track In2And, due to the influence of the ionosphere.

Determine the value of the group is Ameriki τ ion2f0radio signals 14, 15, converted to carrier frequency f0on the track B1D, due to the influence of the ionosphere.

Thus, according to measurements of the moments of the radiation and reception of radio signals at the base station determine the components values of the group delay of the radio signals τion3f011, 14, 15, 18, 19, 20, 21, refer to the carrier frequency f0the pistes AB1, B2D and b2A.

Similarly, considering the impact of the ionosphere on the phase velocity of radio signals, it is fair to conclude that under condition (9)) the sum of the Doppler shift on the carrier frequencies f1and f2equal to the Doppler shift on the carrier frequency f0for signals propagating along the same route from the space vehicle to the docking station.

Next, using the approach detailed in the prototype (patent RF №2323860), determine the distance of 12(B1D) from the space vehicle 6 to the docking station 2:

When implementing the method (including the formation, encoding, transmission, conversion, reception and processing of radio signals, the tropospheric correction, hardware and other components of the measurement) can be used known hardware and software solutions, such applied in PRARE (http:/geodaf.mt.asi.it/html_old/prare/prare.html) - the system accurately determine range, increments of the range and parameters of the ionosphere, and is also used in global positioning systems GPS, GLONASS, Galileo, WAAS, and others (see, for example, http://www.colorado.edu/geography/gcraft/notes/gps/gps/_ftoc.html, http://europa.eu.int/comm/dgs/energy_transport/galileo/documents/technical_en.htm, http://glonass-gps.blogspot.com/).

When determining distances in addition to the Doppler frequency shift N can be used and other relations, containing information about the Doppler frequency shift of the emitted and received signals, such as Doppler account for a certain period of time, the ratio of the instantaneous values of the frequency integral of the Doppler account etc. by converting the corresponding equations.

In addition, as new models and algorithms, linking the magnitude of group and phase delays of radio signals (7) with the parameters of the ionosphere, can be appropriately adjusted by the above equations (8) and (9)that determine the choice of transformation coefficients of frequency for coherent retransmissions of radio signals. Also to improve the accuracy of the proposed method can be used multi-frequency measurements.

The effectiveness of inventions

The present invention allows simultaneous measurements of distances between the spacecraft, the primary and secondary stations (the number of ignoreme the but additional stations are not limited to), with high accuracy (taking into account the influence of the Earth's ionosphere on the measurement results in real time. This provides increased accuracy and efficiency measure distances between spacecraft and stations, as their definition is made immediately after receiving the measurement data. Does not require knowledge of the exact parameters of the orbits of these satellites, because the definition of these parameters can be made directly in the measurement process.

In addition, the present invention provides the radiation, reception, processing all of the signals to one station that gives you the ability to remotely and simultaneously to determine the values of the integral e concentration (TEC) on the propagation paths of the radio signals from the spacecraft to stations without the need for collection and transmission of additional data.

Also, the present invention makes it possible to establish more Autonomous stations in earthquake-prone-to-reach areas to determine their coordinates and values of the integral of the electron concentration (TEC) in the ionosphere in the area of installation of these stations.

In addition, the present invention can be used in conjunction with space systems sensing of the Earth's atmosphere, and positioning systems for the co the Noi navigation bindings spacecraft used in the global positioning system objects (GPS, Gallileo, GLONASS, WAAS, EGNOS and others), with the purpose of refining the orbits of spacecraft that are in the system, their relative position and the positions of the tracking stations, data for ionospheric correction and increase thereby the precision of the positioning of the designated objects (see, for example, http://www.glonass-center.ru/; ; http://www.gallileolonass-center.ru/).

In addition, the proposed method can be used for mutual synchronization and binding of different navigation systems (GPS, Gallileo, GLONASS and other) to each other with the aim of creating a global system for correcting ionospheric errors in positioning and thereby increasing the accuracy of determining the coordinates of the objects using any of these systems or any combination thereof.

The creation of an integrated network of Autonomous stations in earthquake-prone areas of the planet can afford to conduct ongoing monitoring of the ionosphere and the displacement of local points on the surface of the Earth with reference to the common coordinate system and the identification of local dynamics and General laws, considering the Earth as a whole as the physical body is exposed to various types of disturbances of different nature.

The list of positions and letter symbols used in the description.

1 - the main station; 2 - additional station; 3 - station antenna 1; 4 - antennas is and station 2; 5 - orbit of the spacecraft; 6 - spacecraft; 7 antenna of the spacecraft; 8 - point (1) orbit 5 spacecraft; 9 - point (2) orbit 5 spacecraft; 10 - point (3) orbit 5 spacecraft; 11 - primary radio; 12 - primary signal; 13 - additional primary signal; 14 - primary signal; 15 - additional primary signal; a 16 - end signal; 17 - additional target radio signal; an 18 - end signal; 19 - auxiliary destination radio; 20 - additional target radio signal; 21 - additional auxiliary target radio signal;

l1- the distance between the spacecraft 6 and the main station 1; t0the moment of radiation of the primary signal 10 with the base station 1;

l2- the distance between the spacecraft 6 at the time of its location in point 8 (1) orbit 5 and additional station 2; C is the speed of propagation of radio waves;

t11- the moment of reception of the primary signal at the base station;

t12- the date of the receipt of additional primary signal at the base station;

t0the moment of radiation of the primary signal from the primary station;

N1and t211accordingly Doppler shift of the carrier frequency and the time of reception of a horse the nogo signal, received at the base station;

N2and t212accordingly Doppler shift of the carrier frequency and the time of reception of the auxiliary end signal at the base station;

N3and t221accordingly Doppler shift of the carrier frequency and the time of reception of the additional end signal at the base station;

N4and t222accordingly Doppler shift of the carrier frequency and the time of reception of the additional auxiliary end signal at the base station;

t11- the moment of reception of the primary signal at the base station; t12- the date of the receipt of additional primary signal at the base station;

m1- conversion of the carrier frequency of the radio signal when it is coherent relay on the spacecraft in the form of initial, final and additional target radio signal; m2- conversion of the carrier frequency of the radio signal when it is coherent relay on the spacecraft in the form of additional primary, auxiliary end and supporting additional target radio signal;

f0the primary carrier frequency of the radio signal radiated from the primary station; f1-211- carrier frequency end of the radio signal received at the base station; f1-212 - carrier frequency of the auxiliary end of the radio signal received at the base station; f1-221- carrier frequency additional target radio signal received at the base station; f2-222- carrier frequency auxiliary additional target radio signal received at the base station;

h1- conditional height at which begins to show the influence of the ionosphere in the area of the base station 1; r is a conditional thickness of the layer of the ionosphere; h2- conditional height at which begins to show the influence of the ionosphere in the area of the docking station 2.

1. The method of determining the distance between the spacecraft and stations, including the primary radiation of the radio signal from the base station in the direction of the spacecraft, the reception of the primary signal on the spacecraft, the primary relay the radio signal from the spacecraft in the direction of the main station, the reception of the primary signal at the base station, the measurement of the moments of emission and reception, respectively, of the primary signals at the base station, the implementation of the radio communication end signal of the spacecraft with at least one additional station by relaying the primary radio signal from the spacecraft to a secondary station, the reception of the primary signal on the play station, convert it to the target radio signal by the relay in the direction of the spacecraft and the reception of the end signal on the spacecraft, retransmission destination radio signal from the spacecraft in the direction of the main station and its reception at the base station, the measurement of the moment of reception of the end signal at the base station, the measurement of Doppler shifts of the carrier frequencies of the radio signals received at the base station, the measurement of time intervals by which to judge the distance between the spacecraft and the primary and secondary stations, characterized in that it further primary relay the radio signal from the spacecraft in the form of at least one additional primary signal in the direction at the main station, take additional primary signal at the base station and measure the time of reception of this signal, the primary relay the radio signal from the spacecraft in the direction of additional stations in the form of at least one additional primary signal, take it to a secondary station and a relay in the form of additional target signal in the direction of the spacecraft, take it on the spacecraft and relay it with the spacecraft in the form of, at least, about the nogo additional target signal in the direction of the main station, accept the end signal and an additional final signal on the spacecraft and relay them to the form, respectively, an auxiliary end and/or additional auxiliary end signal in the direction of the main station, take these radio signals at the base station and measure the moments of reception of these signals, and as time intervals, which further define the distance between the spacecraft, the primary and secondary stations measure the time intervals between the moment of emission of the primary radio signal from a base station, the moments of reception at the base station of the primary and additional primary signal and the moments of reception at the base station of the destination radio, additional end radio, auxiliary end signal and/or additional auxiliary end signal.

2. The method according to claim 1, characterized in that when receiving a primary, final, additional end of radio signals on the spacecraft and relay these signals from the satellite in the form of primary, additional primary signal end, additional finite auxiliary end and supporting additional end signals the transformation is the use of these signals operate coherently with the following conditions:
,
where m1- conversion of the carrier frequency of the radio signal when it is coherent relay on the spacecraft in the form of initial, final and additional end signals;
m2- conversion of the carrier frequency of the radio signal when it is coherent relay on the spacecraft in the form of additional primary, auxiliary end and supporting additional target signals.

3. The method according to claim 2, characterized in that as time intervals, which define the distance between the spacecraft in each of its locations in orbit and additional station, measure the intervals between the moments of emission and reception of the primary signal, the moments of the radiation of the primary signal and receive additional primary signal and the moments of reception of the primary and additional primary signal at the base station, and the distance (l1between the satellite and main station is determined by the ratio
,
where C is the speed of radio wave propagation;
t11- the moment of reception of the primary signal at the base station;
t12- the date of the receipt of additional primary signal at the base station;
t0/sub> the moment of radiation of the primary signal from the primary station.

4. The method according to claim 1 or 2, characterized in that as time intervals, which define the distance between the spacecraft in each of its locations in orbit and additional stations measure the intervals between the sum of the moments of reception of the primary and additional primary signal and accordingly the sum of the moments of the reception end and the auxiliary end of the radio signals and the sum of the moments of reception of the additional target and auxiliary additional target signals at the base station, and the distance (l2) between the spacecraft and the additional station is determined by the ratio

where N1and t211accordingly Doppler shift of the carrier frequency and the time of reception of the end signal, received at the base station;
N2and t212accordingly Doppler shift of the carrier frequency and the time of reception of the auxiliary end of the radio signal received at the base station;
N3and t221accordingly Doppler shift of the carrier frequency and the time of reception of the additional end of the radio signal received at the base station;
N4and t222accordingly Doppler shift of the carrier frequency and momenteraly additional auxiliary end signal, received at the base station;
t11- the moment of reception of the primary signal at the base station;
t12- the date of the receipt of additional primary signal at the base station;

5. The method according to claim 4, characterized in that the said Doppler shifts (N1N2N3N4) carrier frequency end of the radio signal determined from the ratios of the
N1=(m1f0-f1-211)/(2m1f0);
N2=(m2f0-f2-212)/(2m2f0);
N3=(m1f0-f1-221)/(2m1f0);
N4=(m2f0-f2-222)/(2m2f0),
where m1- conversion of the carrier frequency of the radio signal when it is coherent relay on the spacecraft in the form of initial, final and additional end signals;
m2- conversion of the carrier frequency of the radio signal when it is coherent relay on the spacecraft in the form of additional primary, auxiliary end and supporting additional end signals;
f0the primary carrier frequency of the radio signal radiated from the primary station;
f1-211- carrier frequency end of the radio signal received at the base station;
f1-212- carrier frequency auxiliary end radios the persecuted, received at the base station;
f1-221- carrier frequency additional target radio signal received at the base station;
f2-222- carrier frequency auxiliary additional target radio signal received at the base station.

6. The method according to claim 1, characterized in that in the case of many additional stations the measurement of time intervals between the moment of emission of the primary radio signal from a base station, the moments of reception at the base station of the primary and additional primary signal and the moments of reception at the base station of the destination radio, additional end radio, auxiliary end signal and/or additional auxiliary end signal, which determines the distance between the spacecraft and each of the many additional stations carry the same primary signal radiated from the primary station.



 

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