RU2525343C1 - Method for simultaneous determination of six motion parameters of spacecraft when making trajectory measurements and system for realising said method - Google Patents

Abstract

FIELD: radio engineering, communication.

SUBSTANCE: group of inventions relates to methods and means of making spacecraft trajectory measurements using radio links. The method employs three spaced-apart measurement stations. The first measurement station operates in coherent query mode and measures relative range and velocity of the spacecraft and records the time of arrival of the response transmission of the range query from the spacecraft. The other two measurement stations operate in non-coherent non-query mode. Said stations receive a response (frequency-shifted) signal from the spacecraft generated from the query signal of the first measurement station. Based on the received signal, said two measurement stations determine the range and velocity of the spacecraft relative to said measurement stations, as well as the time of arrival of the response transmission of the query from the spacecraft. Information received from said three measurement stations is transmitted to a ballistic centre for processing.

EFFECT: more accurate determination of the trajectory of a spacecraft.

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Description

Technical field

The invention relates to the field of astronautics, and in particular to systems of trajectory measurements of spacecraft.

State of the art

It is known [1] that to determine the trajectory of the spacecraft (SC) and predict its further motion, the results of trajectory measurements performed by ground-based measuring stations (IS) (2, 3, 4) and the onboard transponder of the spacecraft (1) are used (see Fig. .one).

, угол места КА (β), скорость изменения этого угла $$\left(\dot{\beta }\right)$$

, азимутальный угол положения КА относительно ИС (α) и скорость изменения этого угла (α).In the general case, to determine the spacecraft motion path, it is necessary to measure six spacecraft motion parameters: the inclined range from the IS to the spacecraft (R), the radial component of the spacecraft’s speed relative to the IS $$\left(\dot{R}\right)$$

, spacecraft elevation angle (β), rate of change of this angle $$\left(\dot{\beta }\right)$$

, the azimuthal angle of the spacecraft relative to the IS (α) and the rate of change of this angle (α).

, которые последовательно измеряются несколькими ИС (2, 3, 4) территориально разнесенными в широтном и долготном направлениях. При такой схеме измерений в большинстве случаев погрешности определения траектории движения КА оказываются в пределах, достаточных для решения задач управления КА. При этом для расчета траектории используются шесть параметров движения, измеряемых последовательно несколькими ИС: R₁ $${\dot{R}}_1$$

- измеряемыми ИС1 (2, 8, 9, 10, 11, 12), R2, $${\dot{R}}_2$$

- измеряемыми ИС2 (3, 8, 9, 10, 11, 12) и R3, $${\dot{R}}_3$$

- измеряемыми ИС3 (4, 8, 9, 10, 11, 12). Измерения указанных параметров производятся в разное время, поэтому при расчете траектории движения КА все измерения приходится пересчитывать на одно и то же время, что приводит к увеличению погрешностей и, как следствие, к снижению точности определения траектории КА, что является основным недостатком указанного способа траекторных измерений КА.The IC, which can measure all six parameters of the spacecraft motion, is a very complex and expensive device. In practice, when conducting trajectory measurements, only two motion parameters of the KA- (R) and $$\left(\dot{R}\right)$$

, which are successively measured by several IS (2, 3, 4) geographically spaced in latitudinal and longitudinal directions. With this measurement scheme, in most cases, errors in determining the trajectory of the spacecraft are within the limits sufficient to solve the spacecraft control problems. In this case, six motion parameters are used to calculate the trajectory, measured successively by several IPs: R ₁ $${\dot{R}}_{\mathrm{one}}$$

- measured IP1 (2, 8, 9, 10, 11, 12), R2, $${\dot{R}}_2$$

- measured IP2 (3, 8, 9, 10, 11, 12) and R3, $${\dot{R}}_3$$

- measured IP3 (4, 8, 9, 10, 11, 12). The measurements of these parameters are made at different times, therefore, when calculating the trajectory of the spacecraft, all measurements have to be recounted at the same time, which leads to an increase in errors and, as a result, to a decrease in the accuracy of determining the trajectory of the spacecraft, which is the main disadvantage of this method of trajectory measurements KA.

The structural diagram of the method and system of sequential measurements of the motion parameters of the spacecraft (analogue) is presented in figure 1.

Disclosure of invention

The claimed method and system for the simultaneous determination of six parameters of the motion of the spacecraft during trajectory measurements are aimed at eliminating the disadvantage of the analogue.

The technical result of the claimed invention in comparison with analogues is to provide higher accuracy in determining the flight path of the spacecraft.

The technical result is achieved by the fact that a method for simultaneously determining six parameters of the motion of a spacecraft (SC) during trajectory measurements, which consists in generating a request signal from a ground-based interrogation measuring station, transmitting a signal to a signal receiver of the spacecraft, receiving, processing and generating from a request the signal in the coherent frequency converter of the spacecraft is a highly stable response signal, at the same time relay from the transmitter of the spacecraft highly stable the first response signal to the ground interrogation measuring station, as well as the first and second ground non-interrogation measuring stations, while the ground interrogation measuring station measures the distance from it to the spacecraft, the speed component of the spacecraft relative to the ground interrogation measuring station and the time it takes to receive a highly stable response signal from the spacecraft in interrogative coherent mode, and the first and second groundless interrogating measuring stations operating in non-interrogating incoherent mode determine radial the spacecraft velocity relative to the first and second groundless request-free measuring stations and the time of receiving a highly stable response signal from the spacecraft, using for measurements the received highly stable response signal from the spacecraft, formed from the request signal of the ground-based interrogation measuring station, according to the data of the time of receipt of the highly stable signal by three ground-based measurement the stations and the measured distance value by the ground interrogating measuring station to the spacecraft in the ballistic center determine the range from the first and second groundless request-free measuring stations to the spacecraft.

The system for the simultaneous determination of six parameters of the motion of the spacecraft during trajectory measurements includes a spacecraft (KA), in which the KA signal receiver, the coherent KA frequency converter, the KA transmitter, the KA transceiver antenna, the output of which is connected to the receiver input, are located spacecraft signals, and the input is connected to the output of the spacecraft transmitter, a ground-based interrogation measuring station, which includes the first ground-based signal receiver, the first trajectory system measurements, the first input of which is connected to the first output of the first ground-based signal receiver, the first exact frequency generator, the third output of which is connected to the second input of the first ground-based signal receiver, the first output with the second input of the first trajectory measurement system, a coherent frequency converter, the first input of which is connected to the second output of the first generator of exact frequencies, the second input is connected to the output of the first ground-based signal receiver, a ground-based transmitter, the first input of which is connected to the output of the first gene precision frequency converter, the second input is connected to the first output of the coherent frequency converter, the transceiver antenna, the input of which is connected to the output of the ground transmitter, and the output is connected to the first input of the first ground signal receiver, the first, second and third outputs of the first trajectory measurement system are the first and second outputs of the ground interrogation measuring station, the first ground non-interrogating measuring station, which includes the first receiving antenna, the second ground-based signal receiver, the first input to the second is connected to the output of the first receiving antenna, the second trajectory measurement system, the second input of which is connected to the output of the second ground-based signal receiver, the second exact frequency generator, the first output of which is connected to the first input of the second trajectory measurement system, and the second output is connected to the second input of the second ground receiver, the first and second outputs of the second trajectory measurement system are the first and second output of the first ground-free measuring station, the second ground-level measuring device station, which includes a second receiving antenna, a third ground-based signal receiver, the first input of which is connected to the output of the second receiving antenna, a third path measurement system, the second input of which is connected to the output of the third ground-based signal receiver, and a third exact frequency generator, the first output of which is connected with the first input of the third trajectory measurement system, and the second output connected to the second input of the third ground receiver, the first and second outputs of the third trajectory measurement system are the first and orym yield a second ground bezzaprosnoy measuring station.

Brief Description of the Drawings

The features and essence of the claimed invention are explained in the following detailed description, illustrated by the drawings, which show the following. Figure 1 is an analog of the claimed method and system, where:

1. Spacecraft KA;

2. The first ground measuring station IS1;

3. The second ground measuring station IS2;

4. Third ground measuring station IS3;

5. KA transmitter;

6. Coherent AC frequency converter;

7. The receiver of the spacecraft signals;

8. The first ground-based signal receiver;

9. The first system of trajectory measurements;

10. The first generator of exact frequencies;

11. The first coherent frequency converter;

12. The first ground transmitter;

13. The second ground-based signal receiver;

14. The second system of trajectory measurements;

15. The second generator of exact frequencies;

16. The second coherent frequency converter;

17. The second ground transmitter;

18. The third ground-based signal receiver;

19. The third system of trajectory measurements;

20. The third generator of exact frequencies;

21. The third coherent frequency converter;

22. Third ground transmitter;

23 KA transceiver antenna;

24. The first transceiver antenna;

25. The second transceiver antenna;

26. The third transceiver antenna;

27. Request signal IS1;

28. Request signal IS2;

29. Request signal IS3;

30. The response signal of the spacecraft to the signal IS1;

31. The response signal of the spacecraft to the signal IS2;

32. The response signal of the spacecraft to the signal IS3.

Figure 2 - the inventive method for the simultaneous determination of six parameters of the motion of the spacecraft during trajectory measurements and a system for implementing this method.

33. Spacecraft KA;

34. Ground interrogation measuring station IP;

35. The first land-based non-request measuring station IS1;

36. The second groundless request-free measuring station IS2;

37. Transmitter KA;

38. Coherent AC frequency converter;

39. The receiver of the spacecraft signals;

40. First ground-based signal receiver;

41. The first system of trajectory measurements;

42. The first generator of exact frequencies;

43. Coherent frequency converter;

44. Terrestrial transmitter;

45. The second ground-based signal receiver;

46. The second system of trajectory measurements;

47. The second generator of exact frequencies;

48. Third terrestrial signal receiver;

49. The third system of trajectory measurements;

50. The third generator of exact frequencies;

51. Transceiver antenna of the spacecraft;

52. Transceiver antenna;

53. The first receiving antenna;

54. The second receiving antenna;

55. Request signal IP;

56. The response signal of the spacecraft to the signal IP.

Figure 3 - calculation algorithm in the ballistic center.

The implementation of the invention

The inventive method for the simultaneous determination of six parameters of the motion of the spacecraft during trajectory measurements and the system for implementing this method, as well as analogues, involve the use of geographically dispersed ground-based ISs, but differ from the analogues in the following:

. Кроме того, наземная запросная ИС определяет и регистрирует время прихода ответной посылки запроса дальности с КА - T₁ (40, 41, 42, 43, 44);- of the three ICs (34, 35, 36), only one terrestrial (IS) (34) operates in the interrogation (coherent) mode and measures R ₁ and $${\dot{R}}_{\mathrm{one}}$$

. In addition, the ground-based interrogation IC determines and records the time of arrival of the response request of the range request from the spacecraft - T ₁ (40, 41, 42, 43, 44);

- surface bezzaprosnye IS1 and IS2 operate in bezzaprosnom (incoherent) mode, and receiving a response signal from the SC - ƒ _holes (56) formed from the interrogation signal ƒ _{lock the} terrestrial IP interrogation (55) and shifted relative thereto by frequency.

и $${\dot{R}}_3$$

соответственно, а так же время прихода с КА ответной посылки запроса дальности наземной беззапросной ИС1 - Т₂ (45, 46, 47) и наземной беззапросной ИС2 - Т₃.(48, 49, 50).Based on the received signal from the ground-based unquestioning IS1 and IS2, determine $${\dot{R}}_2$$

and $${\dot{R}}_3$$

respectively, as well as the time of the arrival from the spacecraft of the response request for the range of the ground unquestioning IS1 - T ₂ (45, 46, 47) and the ground unquestioning IS2 - T _3. (48, 49, 50).

The information received by ground-based ICs, IS1 and IS2 is transmitted to the ballistic center (BC) (see Fig. 3), where the difference in the delays of the transmission of the response range signal is determined - ΔT _1-2 and ΔT _1-3 , where ΔT _1-2 = T ₁ -T ₂ , ΔT _1-3 = T ₁ -T ₃ , and the difference in the values of the distance from the ground IS to the spacecraft is determined:

ΔR _1-2 = ΔT _1-2 · C,

ΔR _1-3 = ΔT _1-3 · C, where C is the speed of light.

The values of the inclined ranges from the ground-based unquestioning IS1 and IS2 to the spacecraft are defined as

R ₂ = R ₁ + ΔR _1-2 ,

R ₃ = R ₁ + ΔR _1-3 ,

where R _{1 the} value of the slant range between the ground interrogation IP and spacecraft, measured by the interrogation method.

; $${\dot{R}}_2$$

и $${\dot{R}}_3$$

, измеренные одновременно, что повышает точность определения траектории движения КА.Thus, in the BC all six spacecraft motion parameters - R ₁ , are known; R ₂ ; R ₃ ; $${\dot{R}}_{\mathrm{one}}$$

; $${\dot{R}}_2$$

and $${\dot{R}}_3$$

measured simultaneously, which increases the accuracy of determining the trajectory of the spacecraft.

The inventive system for the simultaneous determination of six parameters of the spacecraft motion during trajectory measurements provides for equipping all ground-based ICs with highly stable frequency generators (42, 47, 50).

The inventive method for the simultaneous measurement of all parameters of the motion of the spacecraft can most effectively be used for trajectory measurements of lunar spacecraft and interplanetary spacecraft in the surface flight section at ranges of 1-2 million km.

In the General case, the inventive method can be used for trajectory measurements of any spacecraft, the orbit (trajectory) of which allows you to simultaneously see at least three spaced ground IS, participating in the measurements of R _1, T ₁ , T ₂ and T ₃ , which are used to calculate the values of R ₂ and R ₃ . The six motion parameters obtained determine the trajectory of the spacecraft. Since the measurement of all the parameters of the motion of the spacecraft was carried out simultaneously, the determination of the trajectory of the motion of the spacecraft is made with high accuracy.

Literature

1. Molotov EP Terrestrial radio control systems for spacecraft. M .: FIZMATLIT, 2004.

Claims (2)

1. A method for simultaneously determining six parameters of the motion of a spacecraft (SC) during trajectory measurements, which consists in generating a request signal from a ground-based interrogation measuring station, transmitting a signal to a signal receiver of the spacecraft, receiving, processing and generating it from a request signal in a coherent converter frequencies of the spacecraft a highly stable response signal, at the same time relay a highly stable response signal from the spacecraft transmitter to the ground interrogation and measuring station, as well as on the first and second ground-free measuring stations, while the ground-based interrogation measuring station measures the distance from it to the spacecraft, which is the velocity of the spacecraft relative to the ground-based interrogation measuring station and the time it takes to receive a highly stable response signal from the spacecraft in interrogation coherent mode, and the first and second groundless request-free measuring stations operating in a request-free incoherent mode determine the radial components of the spacecraft velocity relative to howling and the second groundless requestless measuring stations and the time of reception of a highly stable response signal from the spacecraft, using the received highly stable response signal from the spacecraft, formed from the request signal of the ground interrogation measuring station, according to the time of reception of the highly stable signal by three ground measuring stations and the measured value the distance from the ground interrogation measuring station to the spacecraft in the ballistic center determine the distance from the first and second ground unquestioned x measuring stations to the spacecraft. 2. A system for the simultaneous determination of six parameters of the motion of a spacecraft during trajectory measurements, including a spacecraft (KA), in which there are serially connected KA signal receiver, a coherent KA frequency converter and a KA transmitter, a KA transceiver antenna, the output of which is connected with the input of the spacecraft signal receiver, and the input is connected to the output of the spacecraft transmitter, a ground-based interrogation measuring station, which includes a first ground-based signal receiver, a first trajectory system measurements, the first input of which is connected to the first output of the first ground-based signal receiver, the first exact frequency generator, the third output of which is connected to the second input of the first ground-based signal receiver, the first output with the second input of the first trajectory measurement system, a coherent frequency converter, the first input of which is connected with the second output of the first exact frequency generator, the second input is connected to the output of the first ground-based signal receiver, a ground-based transmitter, the first input of which is connected to the output of the first about the exact frequency generator, the second input is connected to the first output of the coherent frequency converter, the transceiver antenna, the input of which is connected to the output of the ground transmitter, and the output is connected to the first input of the first ground signal receiver, the first, second and third outputs of the first trajectory measurement system are the first and the second outputs of the ground interrogation measuring station, the first ground non-interrogating measuring station, which includes the first receiving antenna, the second ground-based signal receiver, the first the path of which is connected to the output of the first receiving antenna, the second trajectory measurement system, the second input of which is connected to the output of the second ground-based signal receiver, the second exact frequency generator, the first output of which is connected to the first input of the second trajectory measurement system, and the second output is connected to the second input of the second ground receiver, the first and second outputs of the second system of trajectory measurements are the first and second output of the first ground-free measurement station, the second ground-free measurement a station, which includes a second receiving antenna, a third ground-based signal receiver, the first input of which is connected to the output of the second receiving antenna, a third path measurement system, the second input of which is connected to the output of the third ground-based signal receiver, and a third exact frequency generator, the first output of which is connected with the first input of the third trajectory measurement system, and the second output connected to the second input of the third ground receiver, the first and second outputs of the third trajectory measurement system are the first and m second output of second ground bezzaprosnoy measuring station.

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