WO2008130272A1

WO2008130272A1 - Method for comparing time scales of stations

Info

Publication number: WO2008130272A1
Application number: PCT/RU2008/000124
Authority: WO
Inventors: Viktor Leonidovich Sorokin
Original assignee: Viktor Leonidovich Sorokin
Priority date: 2007-04-20
Filing date: 2008-03-06
Publication date: 2008-10-30
Also published as: RU2347255C1; RU2007114870A

Abstract

The inventive method for comparing time scales of stations consists in measuring time intervals between the time point t0 of a basic primary radio signal emission from a basic station and time points t1 and t2 of the reception of the basic and additional radio signals, respectively, at the basic station and time points t1 and t3 of the reception of the basic primary and final radio signals at the basic stations by means of a space vehicle and an additional station, in measuring Doppler drifts N1 and N2 of the f1 and f2 carrier frequencies of the primary and final radio signals, respectively, which are received at the basic station, with respect to the relative carrier frequency f0 of the basic primary radio signal emitted therefrom and in determining the drift between the time scales of the basic and additional stations according to formula (I).

Description

METHOD FOR COMPARISON OF TIME SCALES OF STATIONS

Technical field

The present invention relates to the field of organizing a single time service, and more particularly to methods for comparing station time scales and synchronizing station time scales.

The present invention can be used in measurements, scientific research and experiments requiring time synchronization, such as, for example, in the field of positioning, ultra-long base radio interferometry (VLBI), space navigation, geophysics, geodesy, and so on.

In addition, the present invention can be used for interlinking the time scales of spacecraft and stations used in the global positioning system of GLONASS objects (as well as GPS, Gallileo, etc.), with the aim of clarifying the orbits of the spacecraft included in the system, their mutual position and increase, thereby, the accuracy of positioning of defined objects. Also, the proposed method can be used for mutual synchronization and binding of various navigation systems (GPS, GPS, GLONASS, etc.) to each other in order to increase the accuracy of synchronization and determine the coordinates of objects using positioning systems.

State of the art

Currently, more and more attention is paid to improving the accuracy of measurements, scientific experiments and deepening scientific research. Moreover, one of the most important conditions is their coordinate-time support. This requires, in particular, the organization of a single time service, which provides a comparison of the time scales of stations participating in the single time service. In this regard, requirements for increasing the accuracy of comparing station time scales and efficiency by reducing the time required for this comparison are increasing.

A known method of comparing the time scales of the station, which consists in the fact that at one station, the selected reference, expose on the transported

1 SUBSTITUTE SHEET (RULE 26) standard time scale of this item and then in the on state this standard is transported to the second station, the time scale of which is set on the scale of the transported standard (see, for example, Time and frequency. Edited by J. Jesperson et al. Per. S English, Moscow , 1973, p. 46-47).

The main disadvantages of this method are the low efficiency of comparing time scales and reliability, which is associated with the need to transport the standard in the on state.

A known method of comparing the station’s time scales is (High Process Tim Time Compreter Va Satellite Apd Opservep Dis Apherap. Y. Yamototo, K. Narada. IEEE Trans. Instrument 4 477) by radiating the primary primary radio signal from the primary station at a point in time corresponding to a time signal from the time scale of the primary station towards the spacecraft, receiving the primary primary radio signal on the spacecraft, relaying the primary primary radio signal from the spacecraft in the direction and an additional station, receiving the primary primary radio signal at the secondary station, emitting the secondary primary radio signal from the secondary station at a point in time corresponding to a time signal from the secondary station’s time scale, towards the spacecraft, receiving the secondary primary radio signal on the spacecraft, relaying the secondary primary radio signal from the spacecraft towards the main station, receiving an additional primary radio signal to the main station, measuring the moment of emission of the main radio signal at the main station and the moment of receiving the additional primary radio signal at the main station and measuring the time intervals by which the shift between the time scales of the main and additional station is judged.

According to this method, after measuring the moment of emission of the primary radio signal at the base station and the moment of receiving the additional primary radio signal at the base station, the moments of emission of the additional primary radio signal and reception of the primary primary radio signal at the secondary station are measured, and the time intervals are measured by which the shift between time scales is judged

2 SUBSTITUTE SHEET (RULE 26) the primary and secondary stations, carry out the measurement of the time interval between the moments of radiation of the primary primary and receiving the primary primary radio signals at the secondary station and the time interval between the moments of radiation of the primary primary and receiving the secondary primary radio signals at the primary station.

However, according to this method, the separate measurement of time intervals at the corresponding primary and secondary stations, as a rule, does not correspond to the same position of the spacecraft in orbit when it moves relative to these stations, which, in turn, reduces the accuracy of determining the shift between the time scales of the main and additional stations.

SUMMARY OF THE INVENTION

The aim of the present invention is to develop a method of comparing the time scales of stations, which improves the accuracy of determining the shift between the time scales of stations and its efficiency.

This goal is achieved by the fact that in the method of comparing the time scales of stations, they emit a primary radio signal from the main station at a point in time corresponding to a time signal from the time scale of the main station in the direction of the spacecraft, the main primary radio signal is received on the spacecraft, the main primary radio signal is relayed with spacecraft in the direction of the primary and secondary stations, receive the primary primary radio signal at the primary and secondary stations, transform the basis the primary primary radio signal to the final radio signal by relaying to the spacecraft, receive the final radio signal on the spacecraft, relay the final radio signal from the spacecraft in the direction to the main station, receive the final radio signal at the main station, emit an additional primary radio signal from the additional station at a time corresponding to the time signal from the time scale of the additional station, in the direction of the spacecraft, take the additional first primary radio signal on the spacecraft, retransmit the additional primary radio signal from the comic apparatus towards the main station, receive the additional primary radio signal on the main station, measure the moment

3 SUBSTITUTE SHEET (RULE 26) radiation of the main radio signal at the main station, measure the moments of reception of the main and additional radio signals at the main station, measure the time intervals between the moment of radiation of the main primary radio signal and the moments of reception of the main and additional primary radio signals at the main station, the time interval between the moments of reception of the main primary and final radio signals at the main station, Doppler shifts are measured, respectively, of the carrier frequencies of the primary and final of the radio signals received at the base station relative to the carrier frequency of the primary primary radio signal emitted from the primary station, and they make a judgment about the shift between the time scales of the primary and secondary stations according to the measured time intervals and Doppler shifts of the frequencies of the primary and final primary radio signals received respectively the base station, relative to the carrier frequency of the primary primary radio signal emitted from the base station.

The problem that must be solved by means of the invention The invention was based on the task of developing from here a method of comparing time scales between stations having such additional operations, and measuring time intervals by which a shift between the time scales of the main and additional stations is judged would be carried out between such moments that the measurement of time intervals between the moments of emission and reception of radio signals from the primary and secondary stations would correspond to the same position orbit in orbit, or would allow to take into account its displacement in orbit during measurements.

Problem Solving Method

This is achieved by the fact that in the method of comparing the time scales of stations by emitting the primary radio signal from the main station at a point in time corresponding to a time signal from the time scale of the main station, in the direction of the spacecraft, receiving the primary primary radio signal on the spacecraft, relaying the primary primary radio signal with spacecraft in the direction of the additional station, receiving the primary primary radio signal at the additional

4 SUBSTITUTE SHEET (RULE 26) stations, radiation of an additional primary radio signal from an additional station at a point in time corresponding to a time signal from the time scale of an additional station, in the direction of the spacecraft, receiving an additional primary radio signal on the spacecraft, relaying the additional primary radio signal from the spacecraft in the direction of the main station, receiving additional primary radio signal, at the main station, measuring the moment of radiation of the main radio signal at the main station and the moment of receiving the additional primary radio signal at the main station and measuring the time intervals by which the shift between the time scales of the main and additional stations according to the invention is judged, simultaneously with the relay of the main primary radio signal from the spacecraft in the direction to the additional station, this main primary the radio signal in the direction of the main station and receive the main primary radio signal at the main station, simultaneously with the reception of of the new primary radio signal at an additional station, this primary primary radio signal is converted to the final radio signal by relaying to the spacecraft, the final radio signal is received on the spacecraft, the final radio signal is transmitted from the spacecraft towards the main station, and the final radio signal is received at the main station, after measuring the moment radiation of the primary primary radio signal at the base station measures the moments of reception of the primary primary and final ra of signals at the base station, measuring the time intervals by which the shift between the time scales of the primary and secondary stations is judged is carried out by measuring the time intervals between the moment of emission of the primary primary radio signal and the moments of reception of the primary and secondary primary radio signals at the primary station and the time interval between the reception primary primary and final radio signals at the primary station, and before judging a shift between the time scales of the primary and secondary of the base station additionally measure the Doppler shifts, respectively, of the carrier frequencies of the primary and final radio signals received at the primary station, relative to the carrier frequency of the primary primary radio signal emitted from the primary station,

5 SUBSTITUTE SHEET (RULE 26) and carry out a judgment on the shift between the time scales of the primary and secondary stations according to the measured time intervals and Doppler shifts, respectively, of the carrier frequencies of the primary and final radio signals received at the primary station, relative to the carrier frequency of the primary primary radio signal emitted from the primary station.

It is advisable that in the method of comparing the time scales of stations, a judgment on the shift between the time scales of the main and additional stations according to the measured time intervals and Doppler shifts, respectively, of the carrier frequencies of the primary and final radio signals received at the primary station, relative to the carrier frequency of the primary primary radio signal emitted from the primary stations would be carried out according to the following ratio:

_τ = [fe - tо) - (tз-t.) ^{b N2 + N} '- ^(t - ^t0) - (t-to) N ₂ - 2 (t ₂ - to) N, _{+ N2}

2 (1+ Ni) 2 (1 + Ni) 2 (1 + Ni) where τ is the shift of the time scale of the main station relative to the time scale of the secondary station; tо - the moment of radiation of the primary primary radio signal at the base station; ti is the moment of reception of the main primary radio signal at the main station; tg - the moment of reception of an additional primary radio signal at the main station; tz - the moment of reception of the final radio signal at the main station;

Ni is the Doppler frequency shift of the carrier of the primary primary radio signal received at the base station, relative to the frequency of the carrier of the primary primary radio signal emitted from the primary station;

Ng is the Doppler frequency shift of the carrier of the final radio signal received at the base station, relative to the frequency of the carrier of the primary primary radio signal emitted from the base station.

It is desirable that in the method of comparing the time scales of the stations, the Doppler shift of the carrier frequency of the primary primary radio signal received at the primary station relative to the carrier frequency of the primary

6 SUBSTITUTE SHEET (RULE 26) the primary radio signal emitted from the main station would be determined by the following relation;

N. ^ mfo - fO / gmfo, where Ni is the Doppler frequency shift; fi. the carrier frequency of the primary primary radio signal received at the primary station; m is the coefficient of frequency conversion of the carrier of the radio signal during its coherent relay on the spacecraft.

It is reasonable that in the method of comparing the time scales of stations, the Doppler frequency shift of the carrier of the final radio signal received at the main station relative to the carrier frequency of the primary primary radio signal emitted from the main station is determined by the following relation:

N ₂ = (mfo - f ₂ ) / 2mf ₀ , where N ₂ is the Doppler frequency shift; f ₂ . the carrier frequency of the final radio signal received at the base station; m is the coefficient of frequency conversion of the carrier of the radio signal during its coherent relay on the spacecraft.

The present invention allows to determine the shift between the time scales of stations according to the measurement results, which allow you to take into account changes in the position of the spacecraft in orbit, which increases the accuracy of determining the shift between the time scales of stations.

In addition, the present invention provides the reception and processing of all radio signals at one station), which makes it possible to determine the shift between the time scales of the stations at each current point in time.

Also, providing the present invention with the reception and processing of all radio signals at one station reduces the time required to compare the time scales of the stations.

7 SUBSTITUTE SHEET (RULE 26) DETAILED DESCRIPTION OF THE INVENTION

A method of comparing the time scales of stations is that they emit a primary radio signal from the main station at a point in time corresponding to a time signal from the time scale of the main station in the direction of the spacecraft and receive the main primary radio signal on the spacecraft "and then relay the main primary radio signal from the space apparatus in the direction of the primary and secondary stations, receive the primary primary radio signal at the primary and secondary stations and convert to secondary station main primary radio signal to the final radio signal relaying towards the spacecraft. Next, the final radio signal is received on the spacecraft, the final radio signal is relayed from the spacecraft in the direction to the main station, and the final radio signal is received on the main station. An additional primary radio signal is emitted from the additional station at a time corresponding to a time signal from the time scale of the additional station in the direction to the spacecraft, an additional primary radio signal is received on the spacecraft, an additional primary radio signal is transmitted from the spacecraft in the direction to the main station, and an additional primary radio signal at the main station.

Then measure the moment of radiation of the primary primary radio signal at the base station and the moments of reception of the primary and secondary primary and final radio signals at the primary station.

After that, the time intervals between the moments of emission of the primary primary radio signal and the moments of reception of the primary and secondary primary radio signals at the base station, the time interval between the moments of primary and final radio signal reception at the base station and the Doppler shifts of the carrier frequencies of the primary and final radio signals received at the base station, relative to the carrier frequency of the primary primary

8 SUBSTITUTE SHEET (RULE 26) radio signal emitted from the main station.

Based on the measured time intervals and Doppler shifts, respectively, of the carrier frequencies of the primary and final radio signals received at the main station, a shift is judged between the time scales of the primary and secondary stations relative to the carrier frequency of the primary primary radio signal emitted from the primary station.

According to the patented method of comparing the time scales of stations, the judgment on the shift between the time scales of the primary and secondary stations by intentional time intervals and Doppler shifts, respectively, of the carrier frequencies of the primary and final radio signals received at the primary station, relative to the carrier frequency of the primary primary radio signal emitted from the primary station, carried out in the following ratio:

g _{/ h / h} 1- N2 + Nl (tl-tо) (tl-tθ) N2 - 2 (t2 - tθ) Nl,,,, - _{t x t h} τ = [(t ₂ - tо) - (tз - ti) - - - - - L -] / (i + N ₂ - Ni),

2 (1+ Ni) 2 (1 + Ni) 2 (1 + Ni)

where τ is the shift of the time scale of the main station relative to the time scale of the additional station; t ₀ - the moment of radiation of the primary primary radio signal at the base station; ti- moment of reception of the primary primary radio signal at the primary station; t ₂ - time of receiving additional primary radio signal to the primary station; t ₃ - the moment of reception of the final radio signal at the main station; Ni is the Doppler frequency shift of the carrier of the primary primary radio signal received at the base station, relative to the frequency of the carrier of the primary primary radio signal emitted from the primary station;

N ₂ - Doppler frequency shift of the carrier of the final radio signal,

9 SUBSTITUTE SHEET (RULE 26) received at the base station, relative to the carrier frequency of the primary primary radio signal emitted from the base station. In addition, according to the patented method of comparing the time scales of stations, the Doppler frequency shift of the carrier of the primary primary radio signal received at the base station relative to the carrier frequency of the primary primary radio signal emitted from the primary station is determined by the following relation:

Where Ni is the Doppler frequency shift; f ₀ - carrier frequency of the primary primary radio signal emitted from the base station; fi. the carrier frequency of the primary primary radio signal received at the primary station; m is the coefficient of frequency conversion of the carrier of the radio signal during its coherent relay on the spacecraft.

Also, according to the patented method of comparing the time scales of stations, the Doppler frequency shift of the carrier of the final radio signal received at the main station relative to the carrier frequency of the main primary radio signal emitted from the main station is determined by the following ratio:

Brief Description of the Drawings

Other objectives and advantages of the present invention will be shown below when considering the description of an example of its specific implementation with reference to the accompanying drawings, in which:

10 SUBSTITUTE SHEET (RULE 26) FIG. l depicts a structural diagram of a known geodetic system that implements a patented method of comparing time scales of stations;

Figure 2 depicts schematically a time sequence of receiving and transmitting radio signals at stations and spacecraft when implementing the patented method of comparing the time scales of stations.

DETAILED DESCRIPTION OF THE INVENTION

The method is implemented on the well-known geodetic system (High process Tim Time Comprehensive upgrade Abservice Disrupt therapy of SupershopIt. Y. Yamotot, K. Narada. IEEE Transactions, Instrument 4. -477).

Known geodetic system contains the main 1 (Fig.l) and an additional 2 stations each of which has respectively an antenna 3.4. In orbit 5, conventionally shown by the dotted line, the movement of the spacecraft 6 through its points 7.8.9 is indicated. The drawing also shows conventionally designated radio signals. The primary primary radio signal 10 emitted from the primary station 1 in the direction of the spacecraft 6; the primary primary radio signal 11 relayed from the spacecraft 6 in the direction of the base station 1; the primary primary radio signal 12 relayed from the spacecraft 6 in the direction of the additional station 2; an additional primary radio signal 13 emitted from the additional station 2 in the direction of the spacecraft 6; an additional primary radio signal 14 relayed from the spacecraft 6 in the direction of the base station 1; the final radio signal 15 relayed from the additional station 2 in the direction of the spacecraft 6; the final radio signal 16, relayed from the spacecraft 6 in the direction of the main station 1. The main primary radio signals 10,1 1, 12 are determined when the spacecraft 6 is at point 7 (B)) of the orbit 5. Additional primary radio signals 13,14 are determined when located spacecraft 6 at point 8 (B ₂ ) of orbit 5. The final radio signals 15,16 are determined when the spacecraft 6 is at point 9 (B ₃ ) of orbit 5.

Figure 2 additionally schematically shows the time sequences of the reception and transmission of radio signals at station A (I), spacecraft B (6) and station D (2).

11 SUBSTITUTE SHEET (RULE 26) The known geodetic system that implements a method of comparing the time scales of stations 1 (Fig. 1) and 2, works as follows.

At the main station 1, the primary primary radio signal 10 is formed and radiated using an antenna 3 in the direction of the spacecraft 6 moving in orbit 5. This radio signal 10 is emitted at a time corresponding to the time signal to (Fig. 2) of the time scale of station 1. This radio signal 10 receive at time t on a spacecraft 6 located at point 7 of orbit 5, and relay in the direction of the primary 1 and additional 2 stations, respectively, with the primary primary radio signals 1 1 and 12. Then, the primary primary radio is received Igna 1 1 at station 1 (at the time ti), and the main primary radio 12 - an extra station 2 (t _<u). The radio signal 12 at station 2 is converted to the final radio signal 15 by coherent relaying to the spacecraft 6 and the final radio signal 15 is received on the spacecraft 6 (t ₃ ), which during this time will move from point 7 to point 9 of orbit 5. Relay the radio signal 15 s spacecraft 6 in the direction of the main station 1 with the final radio signal 16 and receive this radio signal 16 at the main station 1 (t ₃ ).

At an additional station 2, an additional primary radio signal 13 is generated and emitted by an antenna 4 in the direction of the spacecraft 6. This radio signal 13 is emitted at a time point (tоi) corresponding to the time signal from the time scale of station 2. The radio signal 13 is received on the spacecraft 6 ( t ₂₎ is located at a point 8 5 orbit and retransmitted coherently in the direction of the main station 1 additional primary radio signal 14. Then take additional first radio signal 14 at the main station 1 (t _2).

Next, measure the moment t _{0 of the} radiation of the primary primary radio signal 10 from the primary station 1 and the reception times t _b t ₂ , t _3, respectively, the primary primary 11, additional primary 14 and final 16 radio signals at the primary station 1. Then measure the time intervals (ti - t ₀ ), (t ₂ - t ₀ ), (t ₃ - t]) defined by these moments tо, t \, t ₂ , t ₃ . In addition, the Doppler shift Ni of the carrier frequency fi of the received primary primary radio signal 11 is measured with respect to the carrier frequency fo of the primary primary radio signal 10 emitted from the base station 1.

12 SUBSTITUTE SHEET (RULE 26) Next, measure the Doppler shift N ₂ frequency f ₂ carrier of the final radio signal 16 relative to the frequency f _{0 of the} carrier of the primary primary radio signal 10 emitted from the main station 1.

The measured intervals (ti - t ₀ ), (t ₂ - tо), (t ₃ - ti) time and Doppler shifts Ni, N ₂ determine the shift τ between the time scales of the main 1 and additional 2 stations from the following relation. hours . 1- Ng + Ni (ti- to) (tι-to) N> - 2 (t2-to) Nι ... ... _{t xt} . x = [(t ₂ - tо) - (tз-ti) - L 1 L Л L -] / (i + N ₂ _ N,)

2 (1+ Ni) 2 (1 + Ni) 2 (1 + Ni)

where Ni = (mfo - fi) / 2mf ₀ , and N ₂ = (mf ₀ - f ₂ ) / 2mf ₀ , and m is the carrier frequency conversion coefficient of the primary 10, 13 radio signals and the final radio signal 15 received on the spacecraft 6 in the carrier frequencies of the primary 1 1, 14 and the final radio signal 16, coherently relayed from the spacecraft 6.

Let us consider in more detail the relationships illustrating the implementation of the proposed method.

The distance ABi from the primary measurement station 1 to the spacecraft 6 and the distance BiDi from the secondary measurement station 2 to the space

apparatus 6 (figure 1) correspond to the moment (figure 2) you (where you =) receive and

relaying the radio signal 10 on the spacecraft 6 at point 8 (B]), while the additional measuring station 2 is located at point D.

. _ ti - tо ABi = - - - с, where (1)

C is the propagation speed of radio signals. Express the distance B ₂ A

B ₂ A = AB, + V _ab (fe - ty) = AB! + V _ab [t ₂ - - - ^ - ^ -] (2) with 2

Where V _a - - the average rate of change of distance between the spacecraft 6 and the main measuring station 1 in the time interval

(tbg - ty). We assume that the average speed V _a b in the time intervals (t b ₂ - t b) and (t _{b b} - t b ₂ ) does not change.

From (2)

B ₂ A (I + -) = AB, + V _ab [t ₂ - - ^ - ^] (3) with 2

13 SUBSTITUTE SHEET (RULE 26) Express the distance B ₂ D

B ₀ D is the distance between the spacecraft 6 and the auxiliary station 2 at the time of emission of the radio signal from the auxiliary station 2; V _bd - average rate of change of distance between the spacecraft 6 and additional measuring station 2 in the time interval (t ₂ - You are the). We assume that the average speed V _bd in the time intervals (t ₂ - t ₂ ) and (t ₃ - t ₂ ) does not change. tl + tθ

B ₀ D = B, D + V _bd [tо + τ - - - -], where t ₀ + τ = tоi, then from (4)

t ^{l + tϋ} B ₂ D

B ₂ D = B, D + Vbd [to + τ - ^~ ^ Г ^~ ] + V _bd or

Z s

B ^ D = (5)

(t ₃ -t ₀ ) c = ABi + BiD + DB ₃ + AB ₃ (6)

DB ₃ = BiD + - (BiD + DB ₃ ) or with

DB ₃ (I--) = B ₁ D (I + -) (7) s s

AB ₃ = AB, + - (B ₁ D + DB ₃ ) (8) s

(t ₃ - t _o ) c = AB, + B ₁ D + DB ₃ + AB ₁ + - (B | D + DB ₃ ) = s

= ABi + B ₁ D + DB ₃ + AB, + - B, D + DB ₃ (I + -) = s s

= 2 AB, + B ₁ D (I +) + DB ₃ (1 +) = s s

= 2 AB ₁ + (B ₁ D + DB ₃ ) (I +) = (tz-to) c (9) s

Given the fact that:

(tz - to - ti + to) c (tz - ti) c

(B ₁ D ₊ DB ₃ ) = V _аb =: VГ ^~ 0 °)

1 + 1 + s

We get

14 SUBSTITUTE SHEET (RULE 26) (tz-t _o ) c = 2AB, + 2B, D +> ^or

C C

2B ₁ D = C (t3 - t0 =

=

From here

Define the time relationship for the emission and reception of radio signals (figure 2) at time t ₂

B ₂ AB ₂ D HvA .... t ₂ = to + τ + t _b2 + = t _o + τ + + (13)

C C C

Express the speed V _a and V _bd through the Doppler frequency shifts of the carrier signals f] and f ₂ for the final radio signals 11 and 14, respectively, relative to the carrier frequency f _{0 of the} primary radio signal 10:

To simplify the expression for f], we will temporarily not take into account the component

equations; then you can write:

f, = fo (l-) (1-) .≡fo (l-2) (14)

C C C similarly

Vab Vbd Vbd Vab (Vab + Vbd)

I ₂ = fо (1-) (1-) (1-) (1-) ≡fo (l-2 ^ - ') (15)

C C C C C and then

Express the speeds V _ab and V _bd through the Doppler shifts Ni and N ₂

fifteen

SUBSTITUTE SHEET (RULE 26)

2fo with

^ - (fθ-fc) _ (Vab + Vbd) _(1?)

2fo with

From (12) we obtain, taking into account (16) and (17)

B ₁ D = - ^ ϊL [1- ^] = £ (^ t ₁ ) [I - -] (18)

2 c (l + -) ^{2 1 + Nl}

We transform (5) taking into account (12), (16), (17), (18)

From the expression for (3), taking into account (16) and (17), we find

with Transform (13) taking into account (16) and (17)

VgD VgA t ₂ = to + τ + + = t _o + τ + s

From (21) we obtain:

_{/ 1} ht ht _{h g} (tl-tо) (tl-tθ) ._ _t . _t τ ⁽ l ₊ ^N , - ^N , ⁾ - ^[ . ₂ - “o-

- y- V ^(N2 " ^Nl) "

(I + N.) Finally, from the last expression we get:

16 SUBSTITUTE SHEET (RULE 26) _τ / ₍ i _{+ N} 2 - N,) (22)

This expression can be simplified taking into account the fact that when expanding equation (22), the values of each of the terms (N ₂ ) ² , (Ni) ² , (N ₂ ) (N]) are less than 10 ^" , then

1-N ₂ + Ni (ti-to) (ti-ty) N2 - 2 (t2-tc) Ni

Taking into account the fact that the primary signal 10 emitted from the measuring station 1, when receiving and relaying on the spacecraft 6, is coherently relayed with a transform coefficient m (at station 2, signal 12 is coherently relay with a transform coefficient 1 / m), we finally express the relations used in the relations (22) and (23) expressions (16) and (17) as follows: Ni = (mf _o -f,) / 2mfo = WJc (24)

N ₂ = (mf ₀ -f ₂ ) / 2mfo = (V _ab + V _bd ) / c (25)

Thus, according to the proposed method, it is possible to determine the time shift τ between the time scale of the main measuring station 1 and the time scale of the additional measuring station 2, existing at time t ₀ , corresponding to the time of radiation of the radio signal 10 from the measuring station 1.

When implementing the method (including the formation, transmission, conversion, reception and processing of radio signals, correction of atmospheric and other components of measurements), well-known hardware and software solutions used in global positioning systems GPS, GLONASS, Galileo, etc. ... technical_en.htm).

Both stationary and mobile objects, spacecraft, ships, offshore platforms, etc. can be used as stations.

In determining the time shift τ, in addition to the Doppler frequency shift N, one can use other relationships containing information on the Doppler frequency shift of the emitted and received radio signals (i.e., the rate of change of distances between the spacecraft 6 and stations 1 and 2), for example, the Doppler account for a certain time interval, the ratio of instantaneous frequencies, the integral Doppler count, etc., converting

17 SUBSTITUTE SHEET (RULE 26) correspondingly, equations (14) - (25).

When a spacecraft flies in the radio visibility zone of stations and a series of successive measurements are made, the values of the time shift τ, these values determined using the proposed method can be refined taking into account the real parameters of the motion paths of the spacecraft 6, station 1 and station 2 determined from the data obtained.

In particular, when each determination τ may be adjusted, the average speed V ab, V d on the measurement of time intervals portion (t ₃ - t ₂₎ (t ₂ - You are the) parameters are included in the expression (2), (4) , (14) - (25), the values of the Doppler shift in expressions (14), (15) are refined, all the components in expression (22) are taken into account, and so on.

In addition, according to the results of each series of determining τ, it is advisable to correct the time shift τ between the time scale of the main measuring station 1 and the time scale of the additional measuring station 2 until the minimum values are reached.

The effectiveness of the invention

The present invention allows to determine the shift τ between the time scale of the main measuring station 1 and the time scale of the additional measuring station 2, and the number of additional measuring stations can be unlimited, which can be achieved by comparing and synchronizing the time scales of the network of measuring stations in real time. This provides increased accuracy and efficiency of synchronization of this network, since this does not require preliminary accurate knowledge of the orbits of the spacecraft participating in the synchronization process, and synchronization itself can be carried out immediately after receiving measurement data.

In addition, the present invention provides the reception and processing of all radio signals at one main measuring station, which makes it possible to determine the shift of the time scales τ at each current time without the need for collecting and transmitting additional data.

Also, the present invention allows the use of rather simple radio engineering devices — repeaters, that implements the patented method of the geodetic system, which increases the reliability and mobility of this geophysical system, and also allows you to automate its operation mode.

18 SUBSTITUTE SHEET (RULE 26) As spacecraft it is possible to use artificial Earth satellites (AES) with the most optimal (from the point of view of location geometry measuring stations - AES) orbit parameters. In this case, knowledge of the exact parameters of the orbits of these satellites is not required, and the determination of the shift parameters τ of the time scales can be made directly in the measurement process.

Repeaters can be installed on numerous satellites intended for monitoring the state of the Earth’s atmosphere and weather forecasting.

In addition, the present invention can be used for interlinking the time scales of spacecraft and stations used in the global positioning system of GLONASS objects (as well as GPS, Gallileo, etc.), with the aim of clarifying the orbits of the spacecraft included in the system, their mutual position and increase, and thereby, the accuracy of positioning of defined objects (see for example: http: //www.glonass-center.gu/; http://www.igeb.gov/; http: //www.gallileolonass-center .ru /).

At the same time, the aforementioned repeaters can be additionally installed on the satellite of navigation systems, the option of programmed reprogramming of the standard radio systems of these satellite to implement the proposed method can also be considered.

Also, the proposed method can be used for mutual time synchronization and linking various navigation systems (GPS, Gallileo, GLONASS, etc.) to each other in order to improve the accuracy of synchronization and determine the coordinates of objects using positioning systems and / or their joint systems.

The list of positions and letters used in the description of the invention

1 - main station

2 - additional station,

3 - antenna station 1;

4 - antenna station 2;

5 - the orbit of the spacecraft;

6 - spacecraft;

7, 8, 9, B ₀ - points of the orbit 5 (Bi), (B ₂ ), (B ₃ ), B ₀ ; 10, 1 1, 12 - main primary radio signals

19 SUBSTITUTE SHEET (RULE 26) 13 - additional primary radio signal,

14 - an additional primary radio signal;

15, 16 - final radio signals; τ is the shift of the time scales of stations 1 and 2;

Ni is the Doppler frequency shift fi of the carrier of the primary primary radio signal 11 received at the base station 1, relative to the frequency f _{0 of the} carrier of the primary primary radio signal 10 emitted from the base station;

Ng is the Doppler frequency shift f _{> of the} carrier of the final radio signal 16 received at the base station 1, relative to the frequency f _{0 of the} carrier of the primary primary radio signal 10 emitted from the base station; t ₀ - the moment of radiation of the radio signal 10 at station 1; ti is the moment of receiving the radio signal 1 1 at station 1. t ₂ is the moment of receiving the radio signal 14 at station 1; t ₃ - the moment of reception of the radio signal 16 at station 1; f ₀ - carrier frequency of the primary primary radio signal 10; fi is the carrier frequency of the primary primary radio signal 1 1; f ₂ - carrier frequency of the final radio signal 16; m is the frequency conversion coefficient of the carrier of the radio signal when it is coherently relayed on the spacecraft 6. toi is the moment of emission of the radio signal 13 at station 2; ty - the moment of receiving the radio signal 10 on the spacecraft 6 t ₂ - the moment of receiving the radio signal 13 on the spacecraft 6; t ₃ - - the moment of reception of the radio signal 15 on the spacecraft 6; tdi - receiving radio signal 12 at station 2; C is the propagation speed of radio signals.

20 SUBSTITUTE SHEET (RULE 26)

Claims

CLAIM

1. A method of comparing the time scales of stations by emitting a primary radio signal from the main station at a point in time corresponding to a time signal from the time scale of the main station in the direction to the spacecraft, receiving the main primary radio signal on the spacecraft, relaying the main primary radio signal from the spacecraft in the direction to an additional station, receiving a primary primary radio signal at an additional station, emitting an additional primary radio signal from an additional station at a point in time corresponding to a time signal from the time scale of the additional station, in the direction to the spacecraft, receiving the additional primary radio signal on the spacecraft, relaying the additional primary radio signal from the spacecraft in the direction to the main station, receiving the additional primary radio signal at the main station, measuring the moment of emission of the primary primary radio signal at the base station and the moment of reception of the additional primary radio signal at the main station and measuring the time intervals by which the shift between the time scales of the primary and secondary stations is judged, which is the same as simultaneously with the relay of the primary primary radio signal from the spacecraft in the direction of the secondary the station retransmits this primary primary radio signal in the direction to the primary station and receives the primary primary radio signal at the primary station, simultaneously with the reception of the primary primary radio signal at the secondary station convert this primary primary radio signal to the final radio signal by relaying to the spacecraft, receive the final radio signal to the spacecraft, relay the final radio signal from the spacecraft to the main station and receive the final radio signal at the main station, after measuring the moment of radiation of the primary primary radio signal to the main stations measure the moments of reception of the main primary and final radio signals at the main station, the measurement of time intervals not used to judge the shift between the time scales of the primary and secondary stations, measure the time intervals between the moment of emission of the primary primary radio signal and the moments of reception, respectively, of the primary and secondary primary radio signals at the primary station and the time interval between the moments of reception

21 SUBSTITUTE SHEET (RULE 26) of the primary and final radio signals at the base station, and before judging the shift between the time scales of the primary and secondary stations, Doppler shifts are additionally carried out, respectively, of the carrier frequencies of the primary and final radio signals received at the primary station, relative to the carrier frequency of the primary primary radio signal emitted from the primary stations, and carry out a judgment on the shift between the time scales of the primary and secondary stations according to the measured time intervals and Doppler frequency shifts, respectively carrying the main primary and end radio signals received at the main station with respect to the main carrier frequency of the primary radio signal emitted from the master station.

2. The method according to claim 1, with the conclusion that the judgment on the shift between the time scales of the primary and secondary stations according to the measured time intervals and the Doppler shift, respectively, of the carrier frequencies of the primary and final radio signals received at the base station, relative to the carrier frequency of the primary primary radio signal emitted from the base station is carried out according to the following ratio:

τ - [te- ..) - (tz- .θ '- ^{Ng + Nl} - <"-"> - <"-'°> ^Ng - ^{2 (h} - ^to > ^N '] / ₍₁ + N _; - N,) 2 (1+ Nr) 2 (1 + Ni) 2 (1 + NL)

where τ is the shift of the time scale of the main station relative to the time scale of the additional station; t ₀ - the moment of radiation of the primary primary radio signal at the base station; ti is the moment of reception of the main primary radio signal at the main station;

Xi is the moment of reception of the additional primary radio signal at the main station; tz - the moment of reception of the final radio signal at the main station;

N ₂ - Doppler frequency shift of the carrier of the final radio signal received at the base station, relative to the carrier frequency of the primary primary

22 SUBSTITUTE SHEET (RULE 26) radio signal emitted from the main station.

3. The method according to claim 2, characterized in that the Doppler frequency shift of the carrier of the primary primary radio signal received at the base station, relative to the carrier frequency of the primary primary radio signal emitted from the primary station, is determined by the following ratio:

where N ₁ - Doppler frequency shift fо - carrier frequency of the primary primary radio signal emitted at the base station; fi is the carrier frequency of the primary primary radio signal received at the base station; m is the coefficient of frequency conversion of the carrier of the radio signal during its coherent relay on the spacecraft.

4. The method according to claim 2, characterized in that the Doppler frequency shift of the carrier of the final radio signal received at the base station, relative to the frequency of the carrier of the primary primary radio signal emitted from the main station, is determined by the following ratio:

N ₂ = (mf ₀ -f ₂ ) / 2mf ₀ where N ₂ is the Doppler frequency shift f ₂ is the carrier frequency of the final radio signal received at the base station; m is the coefficient of frequency conversion of the carrier of the radio signal during its coherent relay on the spacecraft.

23 SUBSTITUTE SHEET (RULE 26)