A method for detecting orbital maneuvers of GEO satellites based on interferometric data

Abstract

The present invention discloses a GEO satellite orbit maneuver detection method based on interferometric measurement data, which relates to the field of space situation monitoring technology, and mainly solves the problem of real-time detection of non-cooperative GEO satellite orbit maneuvers. The implementation process is: deploy three ground interferometric measurement stations, including a main station and two sub-stations, and simultaneously receive downlink signals from non-cooperative GEO satellites; perform relevant processing on the signals received by the measurement stations to obtain interferometric measurement data of space targets on two baselines, including distance difference and distance difference change rate; establish a data model based on the interferometric measurement data during normal orbit operation and update and correct it in real time, and realize real-time detection of non-cooperative GEO satellite orbit maneuvers by detecting changes in the deviation of the measurement data from the model prediction value. The present invention avoids the establishment of a complex dynamic model, does not require target positioning, has simple calculations, and has good real-time performance.

Description

Technical Field

[0001] The present invention relates to the technical field of space situation monitoring, and in particular to a GEO satellite orbit maneuver detection method based on interferometric measurement data. Background Art

[0002] Compared with low-orbit or medium-orbit spacecraft, the intelligence collection capability of GEO spacecraft's space perception project is more than 600 times that of the former. The competition for resources in this orbit has become obvious, and the GEO orbit is bound to become the main battlefield for space attack and defense. At present, the Earth's GEO orbit includes communication and observation satellites of many countries, the most representative of which is the Geosynchronous Satellite Perception Project (GSSAP).

[0003] Since August 2016, the "Geosynchronous Orbit Space Situational Awareness Program" has been implemented. So far, multiple (GSSAP) satellites have been launched into space to form a satellite constellation, jointly performing patrol and reconnaissance missions on targets in geosynchronous orbit. GSSAP has high-precision orbital maneuvering capabilities. Through relative drift with geosynchronous orbit targets, it can achieve full-orbit patrol detection. The shortest revisit period is about 15 days, which can support the expansion of high-orbit situational awareness capabilities to multiple fields such as target technical reconnaissance and action intention judgment. In addition, GSSAP satellites also have the potential to attack geosynchronous orbit targets. my country's dependence on GEO space resources will deepen. In the face of GSSAP's targeted reconnaissance and potential attacks, in order to meet my country's high-orbit situational awareness needs and maintain the security of GEO satellite resources, we should actively develop space and counter-space capabilities, improve the surveillance capabilities of high-orbit non-cooperative targets in a targeted manner, monitor the location and operating status of non-cooperative GEO satellites, quickly discover abnormal orbital maneuvers, and provide support for optical or radar guided monitoring, continuous key monitoring, enemy behavior identification, anti-close reconnaissance, and counterattack.

[0004] The existing situational awareness systems are mainly based on active radar and optical detection systems, but active radar faces the problem of power-limited detection range and limited detection of GEO space; although the optical detection system can easily overcome the problem of monitoring distance, it is greatly affected by light and meteorological conditions and cannot work all day. For the orbital maneuver detection of non-cooperative GEO satellites, one method is to use radar angle measurement and distance measurement information to obtain the position and speed of the target, and identify the orbital maneuver by analyzing the abnormality of the target position and speed, but the measurement noise will introduce large position and speed errors, resulting in a high recognition misjudgment rate; there is also a SACM method, which judges orbital maneuvers based on the change of the semi-major axis of the spacecraft orbit, and a comprehensive judgment method based on two-row roots. Most of these methods are post-analysis and cannot meet the needs of real-time situation monitoring. Summary of the invention

[0005] The purpose of the present invention is to avoid the shortcomings of the above-mentioned background technology and provide a GEO satellite orbit maneuver detection method based on interferometric measurement data. The present invention adopts a passive detection system, does not actively transmit signals, uses three interferometric measurement stations to receive GEO satellite downlink signals, and performs correlation processing on the main and secondary station signals to obtain high-precision interferometric measurement data. By monitoring abnormal changes in interferometric measurement data, real-time detection of non-cooperative GEO satellite orbit maneuvers is achieved.

[0006] The technical solution adopted by the present invention is:

[0007] A GEO satellite orbit maneuver detection method based on interferometric measurement data comprises the following steps:

[0008] ① Deploy three ground interferometric measurement stations, including one main station and two secondary stations. The baselines formed by the main station and the two secondary stations are perpendicular to each other. The three stations have the same time and frequency source and receive the downlink signals of non-cooperative GEO satellites in real time.

[0009] ②Perform correlation processing on the signals received in real time by the main station and the two secondary stations to obtain the interferometric measurement data from the non-cooperative GEO satellite to the two baselines, including the range difference and the rate of change of the range difference;

[0010] ③ According to the variation law of interferometric measurement data, a data model is established using interferometric measurement data of more than one cycle of normal orbit operation. The data model includes constant parameters, linear offset parameters and cosine oscillation parameters;

[0011] ④ Based on the data model, continuously predict the distance difference and distance difference change rate from the non-cooperative GEO satellite to the two baselines at the next observation time, and calculate the deviation between the actual measurement value from the non-cooperative GEO satellite to the two baselines and the model prediction value;

[0012] ⑤ Set the time window T, perform sliding integration on the two deviation values ​​at the observation time, and take k times the average value of the integral value within an operation cycle as the empirical threshold TH for judging whether the GEO satellite orbit maneuver occurs DOR and TH DOD , where k ≥ 5, set according to actual application conditions;

[0013] ⑥ If there is Vs at the current detection time DOR >TH DOR Or Vs DOD >TH DOD , it is determined that the monitored non-cooperative GEO satellite has undergone orbital maneuvers, otherwise, it is determined that the monitored non-cooperative GEO satellite has not undergone orbital maneuvers, and the interferometric measurement data at the current detection time is used to update and correct the data model; where Vs DOR Vs DODIt is the integral value of the deviation between the actual measurement value of the non-cooperative GEO satellite to the two baselines and the model prediction value at the current detection moment.

[0014] Among them, the deviation value V in step ④ DOR and V DOD The calculation method is:

[0015]

[0016]

[0017] In the formula, DOR 12 、DOR 13 are the actual measured distance differences between the non-cooperative GEO satellite and the two baselines, DOD 12 、DOD 13 are the actual measured distance difference change rates from the non-cooperative GEO satellite to the two baselines, are the distance differences between the non-cooperative GEO satellite and the two baselines predicted by the model, are the changing rates of the distance differences between the non-cooperative GEO satellites and the two baselines predicted by the model.

[0018] Compared with the background technology, the present invention has the following advantages:

[0019] The present invention is based on an interference measurement system and does not actively transmit signals. It is a passive electromagnetic sensing system and has the advantages of long monitoring distance, strong concealment, and all-weather operation. It can quickly detect orbital maneuvers by monitoring abnormalities in high-precision interference measurement data without the need for target positioning or orbit determination, thus avoiding the amplification of measurement errors caused by positioning or orbit determination and having high detection performance. It does not require the establishment of a complex dynamic model, and the calculation is simple with good real-time performance. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is a flow chart of the GEO satellite orbit maneuver detection method based on interferometric measurement data of the present invention.

[0021] Figure 2 It is a schematic diagram of the ground interferometric measurement station of the present invention receiving satellite downlink signals. DETAILED DESCRIPTION

[0022] Reference Figure 1 The specific implementation steps of a GEO satellite orbit maneuver detection method based on interferometric measurement data in this embodiment are as follows:

[0023] Step 1: deploy three ground interferometric measurement stations, including a main station and two secondary stations. The baselines formed by the main station and the two secondary stations are perpendicular to each other. The three stations share the same time and frequency source and simultaneously receive downlink signals from non-cooperative GEO satellites.

[0024] In the embodiment, the three ground stations include a master station 1, a slave station 2 and a slave station 3, which simultaneously receive downlink signals from non-cooperative GEO satellites in real time and transmit the received data to a data processing center located at the master station via an optical fiber link, such as Figure 2 As shown;

[0025] Step 2, performing correlation processing on the signals received in real time by the master station and the two slave stations to obtain interferometric measurement data from the non-cooperative GEO satellite to the two baselines, including the range difference and the range difference change rate;

[0026] Step 3, according to the variation law of the interferometric measurement data, a data model is established using the interferometric measurement data of more than one cycle of normal orbit operation, wherein the data model includes constant parameters, linear offset parameters and cosine oscillation parameters;

[0027] In the embodiment, interferometric measurement data of three normal orbit operation cycles are selected for modeling;

[0028] Step 4: According to the data model, the distance difference and the change rate of the distance difference between the non-cooperative GEO satellite and the two baselines at the next observation time are continuously predicted, and the deviation values ​​between the actual measurement values ​​of the non-cooperative GEO satellite to the two baselines and the model prediction values ​​are respectively calculated;

[0029] Deviation value V DOR and V DOD The calculation method is:

[0030]

[0031]

[0032] In the formula, DOR 12 、DOR 13 are the actual measured distance differences between the non-cooperative GEO satellite and the two baselines, DOD 12 、DOD 13 are the actual measured distance difference change rates from the non-cooperative GEO satellite to the two baselines, are the distance differences between the non-cooperative GEO satellite and the two baselines predicted by the model, are the changing rates of the distance differences between the non-cooperative GEO satellites and the two baselines predicted by the model.

[0033] Step 5: Set the time window T, perform sliding integration on the two deviation values ​​at the observation time, and use k times the average value of the integral value within an operation cycle as the empirical threshold TH for judging whether the GEO satellite orbit maneuver occurs. DOR and TH DOD , where k ≥ 5, set according to actual application conditions;

[0034] In the embodiment, T=2 minutes, k=10;

[0035] Step 6: If there is Vs at the current detection time DOR >TH DOR Or Vs DOD >TH DOD , it is determined that the monitored GEO satellite has undergone orbital maneuvers;

[0036] Step 7: If there is Vs at the current detection time DOR >TH DOR Or Vs DOD >TH DOD , it is determined that the monitored non-cooperative GEO satellite has undergone orbital maneuvers, otherwise, it is determined that the monitored non-cooperative GEO satellite has not undergone orbital maneuvers, and the interferometric measurement data at the current detection time is used to update and correct the data model; where Vs DOR Vs DOD It is the integral value of the deviation between the actual measurement value of the non-cooperative GEO satellite to the two baselines and the model prediction value at the current detection moment;

[0037] Complete GEO satellite orbit maneuver detection based on interferometric measurement data.

Claims

1. A GEO satellite orbit maneuver detection method based on interferometric measurement data, characterized in that , including the following steps: ① Deploy three ground interferometric measurement stations, including one main station and two secondary stations. The baselines formed by the main station and the two secondary stations are perpendicular to each other. The three stations have the same time and frequency source and receive the downlink signals of non-cooperative GEO satellites in real time. ②Perform correlation processing on the signals received in real time by the main station and the two secondary stations to obtain the interferometric measurement data from the non-cooperative GEO satellite to the two baselines, including the range difference and the rate of change of the range difference; ③ According to the variation law of interferometric measurement data, a data model is established using interferometric measurement data of more than one cycle of normal orbit operation. The data model includes constant parameters, linear offset parameters and cosine oscillation parameters; ④ Based on the data model, continuously predict the distance difference and distance difference change rate from the non-cooperative GEO satellite to the two baselines at the next observation time, and calculate the deviation between the actual measurement value from the non-cooperative GEO satellite to the two baselines and the model prediction value; ⑤ Set the time window T, perform sliding integration on the two deviation values ​​at the observation time, and take k times the average value of the integral value within an operation cycle as the empirical threshold TH for judging whether the GEO satellite orbit maneuver occurs DOR and TH DOD , where k ≥ 5, set according to actual application conditions; ⑥ If there is Vs at the current detection time DOR >TH DOR Or Vs DOD >TH DOD , it is determined that the monitored non-cooperative GEO satellite has undergone orbital maneuvers, otherwise, it is determined that the monitored non-cooperative GEO satellite has not undergone orbital maneuvers, and the interferometric measurement data at the current detection time is used to update and correct the data model; where Vs DOR Vs DOD It is the integral value of the deviation between the actual measurement value of the non-cooperative GEO satellite to the two baselines and the model prediction value at the current detection time; Among them, the deviation value V in step ④ DOR and V DOD The calculation method is: V DOR =(LONGING 12 -LONGING 12 ) 2 +(LONGING 13 -LONGING 13 ) 2 V DOD =(DOD 12 -DOD 12 ) 2 +(DOD 13 -DOD 13 ) 2 ; In the formula, DOR 12 、DOR 13 are the actual measured distance differences between the non-cooperative GEO satellite and the two baselines, DOD 12 、DOD 13 are the actual measured distance difference change rate between the non-cooperative GEO satellite and the two baselines, DOR 12 、DOR 13 are the distance differences between the non-cooperative GEO satellites and the two baselines predicted by the model, DOD 12 、DOD 13 are the changing rates of the distance differences between the non-cooperative GEO satellites and the two baselines predicted by the model; Complete GEO satellite orbit maneuver detection based on interferometric measurement data.

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