CN119011774A

CN119011774A - Method and system for tracking and imaging civil airliner by satellite

Info

Publication number: CN119011774A
Application number: CN202411065245.2A
Authority: CN
Inventors: 黄朝围; 王少游; 张波; 刘亦男; 曾齐; 唐琪佳; 曹亮
Original assignee: Shanghai Institute of Satellite Engineering
Current assignee: Shanghai Institute of Satellite Engineering
Priority date: 2024-08-05
Filing date: 2024-08-05
Publication date: 2024-11-22

Abstract

The present application provides a method and system for satellite tracking and imaging of civil airliners, including step 1, receiving ADS-B messages broadcast by civil airliners; step 2, extracting the ICAO address, position, speed and altitude information of the aircraft in each aircraft message; step 3, sorting the aircraft according to the frequency of aircraft message updates, the distance of the aircraft position from the target point, the speed of the aircraft or the flight altitude information of the aircraft; step 4, specifying the strategy for outputting guidance information; step 5, eliminating wild values in the message and sending guidance information to the attitude and orbit control subsystem; step 6, the attitude and orbit control subsystem receives the guidance information and performs trajectory fitting; step 7, quickly pointing and tracking based on the guidance information attitude; step 8, the integrated electronic subsystem sends instructions to the camera subsystem, and the camera starts imaging the target. The present application realizes the continuous tracking and imaging of civil airliners flying in the air by satellites, greatly improving the probability of successful imaging of aircraft.

Description

Method and system for tracking and imaging civil airliner by satellite

Technical Field

The application belongs to the field of satellite tracking imaging of civil airliners, and particularly relates to a satellite tracking imaging method and system of a civil airliner.

Background

After Ma Hang crash event, international civil aviation administration stipulates that global civil aviation passenger plane must install broadcast automatic correlation monitoring system (ADS-B), ADS-B system is a new technology for air management monitoring based on satellite positioning and air-ground and air-air data link communication to complete traffic monitoring and information transmission. The technique can monitor (obtain) information of aircraft position, altitude, speed, heading, takeoff/landing status, etc. and associate with a flight call sign with globally unique ICAO identification. ADS-B messages of each aircraft are marked by flight call signs, namely ICAO numbers, and are not confused with messages of other aircraft. The external receiving system can calculate the position, speed and course information of the civil aircraft according to the information, so as to grasp the movement track of the civil aircraft.

Currently, there is no effective technical means for high resolution imaging of airborne aircraft. The airport perimeter is typically imaged by way of opportunistic measurements so that the probability of capturing an aircraft in flight is very low. The satellite carries the ADS-B receiving processor, can receive wide area ADS-B signals from the satellite orbit, can cover remote areas such as polar regions, deserts, oceans and the like with lower cost. The ADS-B signal in the air can be continuously and in real time acquired through the ADS-B searching and guiding subsystem installed on the satellite. The unique ICAO number of each civil aviation aircraft is matched with the corresponding information such as position, altitude, course and the like, so that the tracking of the whole process of the civil aviation aircraft can be completed, and continuous monitoring imaging of important civil aviation targets is realized. For optical high resolution imaging of aerial targets, there is currently no viable technical means.

The Chinese patent document with publication number CN108768492A discloses an aerial target tracking method based on a satellite-borne ADS-B special message, which is used for receiving the ADS-B message on the satellite, downloading the ADS-B message to the ground for carrying out information support such as ground search and rescue, and the method does not relate to satellite application.

The Chinese patent document with the patent number of CN210640878U discloses an ADS-B signal receiving device and system, which relate to an ADS-B load applied to satellites, can receive ADS-B signals and convert the ADS-B signals into digital signals, and do not relate to on-satellite guidance and tracking;

the Chinese patent document with the authorization bulletin number of CN109920080B discloses a real-time ADS-B-based maintenance method for a black-and-white list of an aircraft target, which relates to the real-time ADS-B-based maintenance method for the black-and-white list of the aircraft target in the field of aircraft target screening, and does not relate to on-board guidance and tracking;

The Chinese patent document with the publication number of CN111585639A discloses a satellite-borne ADS-B message monitoring method, a device and a storage medium, and the invention discloses a monitoring method, a device and a storage medium aiming at the problem that the existing ADS-B message is returned to the ground through a data transmission channel and satellites lack real-time monitoring on the satellite-borne load processing capacity of the ADS-B;

The chinese patent document with publication number CN115164825A discloses an automatic digital guidance system based on ADS-B, which calculates the distance between the position information in the received ADS-B signal and the station, guides the theodolite of the ground station to track the target, and does not involve on-board application. There is no prior art currently directed to methods of satellite guidance, tracking and imaging for civil aircraft.

Disclosure of Invention

Aiming at the defects in the prior art, the application aims to provide a satellite tracking imaging method and system for a civil airliner. The satellite-mounted broadcast type automatic correlation monitoring system receives the ADS-B message broadcast by the civil airliner, realizes continuous tracking imaging of the appointed civil airliner, and can monitor the flight state of the important airliner.

The application provides a satellite tracking imaging method for a civil aviation passenger plane, which comprises the following steps:

firstly, carrying an ADS-B receiving processor by a satellite, receiving an ADS-B message broadcast by a civil aviation aircraft, and driving the message into an accurate time mark of a receiving moment;

Analyzing the ADS-B message, and extracting the information of the aircraft ICAO address, the position, the speed and the height in each aircraft message;

Counting all received aircraft message information, and sequencing the aircraft according to the message update frequency of the aircraft, the distance between the aircraft position and a target point, the speed of the aircraft or the flight height information of the aircraft;

step four, the satellite comprehensive electronic subsystem sends a guiding information output instruction to the ADS-B receiving processor, and a strategy for outputting guiding information is appointed;

Fifthly, the ADS-B receiving processor eliminates the outlier in the message, and the ADS-B receiving processor sends guiding information to the attitude and orbit control subsystem through an RS422 interface;

step six, the attitude and orbit control subsystem receives the guiding information, carries out track fitting after accumulating more than 5 beats of effective guiding information, and continuously updates the fitted track by using the latest 5 beats of guiding information;

Step seven, attitude control is carried out according to the fitted track, so that the satellite points to the airplane, and the attitude control subsystem informs the satellite comprehensive electronic subsystem after controlling the satellite to point to the right position;

and step eight, the comprehensive electronic subsystem sends an instruction to the camera subsystem, and the camera starts imaging the target.

Preferably, the message receiving in the first step includes antenna receiving, radio frequency signal processing and digital information processing;

the radio frequency signal processing is to filter, amplify and analog-to-digital convert the ADS-B radio frequency signal received by the antenna to form a sampling signal;

digital information processing is the processing of an original sampled signal, including: demodulation, header detection, time management processing, extracting effective ADS-B message in signal and noise.

Preferably, in the step two, the analysis of the ADS-B message decodes the ADS-B original message, and calculates the target information according to the ADS-B standard protocol, including: position, altitude, speed information.

Preferably, in the step three, the message information statistics are that aircrafts are classified or ordered in multiple dimensions;

The method comprises the steps of firstly receiving aircraft message information for more than 15s on the satellite, taking the received message information as a sample, classifying the information of the same aircraft according to the flight call sign of the aircraft by the sample, and sorting the sample according to the message update frequency of the message, the distance between the aircraft position and a target point, the speed of the aircraft or the flight height of the aircraft respectively to form a sorting table.

Preferably, the guidance information output instruction in the fourth step includes two types:

one is to set up the satellite to search according to the flight call sign of the aircraft, realize the tracking to the appointed aircraft;

And the other is to screen according to the sorting table, and select one aircraft with highest updating frequency, nearest aircraft position, fastest aircraft speed or highest flying height from the selected aircraft to search.

Preferably, the outlier rejection in the fifth step comprises aircraft rejection outside the field of view and interference message rejection with overlarge position jump;

removing the aircraft which deviates from the field of view by adopting a judging method based on distance constraint, firstly, by using an on-ground command to determine the longitude and latitude (L ₀,B₀) of the center point of a task, and if the longitude L _i and the latitude B _i in the message meet the following conditions at the same time, the message is considered as the message in the field of view,

If the target library is not in the range of the target library, the target library is not put into the target library to be tracked, but is still downloaded through a data transmission channel;

the method comprises the steps of removing an abnormal aircraft message with excessive position jump by adopting a speed constraint criterion, and performing one-round jump judgment on guide information to be output by taking the flight speed of Mach 3 as a threshold value to prevent the jump phenomenon of the aircraft message from affecting tracking, wherein the judgment method comprises the following steps:

The time, longitude and latitude (t _i,L_i,B_i,H_i) of the latest guidance information are differed from the time, longitude and latitude (t _i-1,L_i-1,B_i-1,H_i-1) of the last beat, and the flying speed V is calculated:

wherein, the units of longitude and latitude are radians,

If V is not less than 1020m/s, the guiding information 'update state' is set to 0xF1: the guidance information is hopped.

Preferably, after the wild value is removed, the safety of the guide information is enhanced, the transmission frequency of the guide information is 1Hz, and the guide information is consistent with the broadcasting frequency of the ADS-B message.

Preferably, in the sixth step, track fitting is performed by combining a position message and a speed message, firstly, more than 5 aircraft position points are utilized to deduce a first-order term and a second-order term of the flight track, and aircraft speed is used for restraining, so that the second-order term is corrected; the calculation formula is as follows:

calculating fitting coefficients N of longitude, latitude and altitude according to a unitary quadratic polynomial by using the time, longitude, latitude and altitude (t _i,L_i,B_i,H_i) (i=1, 2,3,4,5, wherein i=5 is the latest beat) of the latest 5 beats _L,N_B,N_H

Wherein, the time matrix T is calculated as follows:

preferably, the camera imaging instruction in the step eight is sent after being judged according to the satellite tracking state, so that imaging is started after tracking is completed without imaging in the process of rapidly pointing to the target.

A satellite-to-civil aircraft tracking imaging system comprising:

the first module is used for carrying an ADS-B receiving processor by a satellite, receiving an ADS-B message broadcast by a civil aircraft, and inputting the message into an accurate time mark of a receiving moment;

The second module is used for analyzing the ADS-B message and extracting the information of the aircraft ICAO address, the position, the speed and the height in each aircraft message;

a third module, configured to count all the received aircraft message information, and order the aircraft according to the message update frequency of the aircraft, the distance between the aircraft position and the target point, the speed of the aircraft, or the flight height information of the aircraft;

a fourth module, which is used for sending a guiding information output instruction to the ADS-B receiving processor by the satellite comprehensive electronic subsystem and designating a strategy for outputting guiding information;

The fifth module is used for eliminating the outlier in the message by the ADS-B receiving processor, and the ADS-B receiving processor sends the guiding information to the attitude and orbit control subsystem through the RS422 interface;

The sixth module is used for receiving the guiding information by the attitude and orbit control subsystem, accumulating more than 5 beats of effective guiding information, then performing track fitting, and continuously updating the fitted track by using the latest 5 beats of guiding information;

The seventh module is used for carrying out attitude control according to the fitted track so that the satellite points to the airplane, and the attitude control subsystem informs the satellite comprehensive electronic subsystem after controlling the satellite to point in place;

And the module eight is used for sending an instruction to the camera subsystem by the comprehensive electronic subsystem, and the camera starts imaging the target.

Compared with the prior art, the application has the following beneficial effects:

1. The application can finish the large-scale searching and capturing of the civil aviation aircraft, and improves the capturing probability of the low-orbit high-resolution optical satellite to the aircraft;

2. the technical method of the application realizes the continuous tracking and imaging of the satellite on the civil airliner flying in the air, greatly improves the success probability of imaging the airplane, and can realize the tracking imaging of the airplane with low cost and high reliability;

3. The technical method of the application can be applied to monitoring and imaging the air flight state of the important civil aviation aircraft;

4. The application realizes autonomous completion of searching, guiding and tracking imaging on the satellite, does not need ground intervention, is convenient for satellite platforms of various scales, and has stronger applicability;

5. The system is stable, reliable and flexible, and can quickly point to the target without losing the target in the process of pointing to the target. The high-resolution imaging effect can be ensured after tracking is stable, various strategies are provided for selecting the airplane targets, the flexibility is high, the strong pertinence can be realized, and the method has high application value.

Drawings

Other features, objects and advantages of the present application will become more apparent upon reading of the detailed description of non-limiting embodiments, given with reference to the accompanying drawings in which:

Fig. 1 is a flow chart of a satellite-to-civil aircraft tracking imaging method.

Detailed Description

The present application will be described in detail with reference to specific examples. The following examples will assist those skilled in the art in further understanding the present application, but are not intended to limit the application in any way. It should be noted that variations and modifications could be made by those skilled in the art without departing from the inventive concept. These are all within the scope of the present application.

The invention provides a satellite tracking imaging method for a civil aviation passenger plane, which comprises the following steps:

step one, a satellite carries an ADS-B receiving processor, receives an ADS-B message broadcast by a civil aviation aircraft, and drives the message into an accurate time mark of a receiving moment.

The message receiving comprises antenna receiving, radio frequency signal processing and digital information processing, wherein the radio frequency signal processing is to filter, amplify and analog-to-digital convert an ADS-B radio frequency signal received by the antenna to form a sampling signal. The digital information processing is to demodulate the original sampling signal, detect the header, manage the time, etc., extract the effective ADS-B message in the signal and noise.

Analyzing the ADS-B message, and extracting the information of the aircraft ICAO address, the position speed and the height in each aircraft message.

ADS-B message analysis is to decode an ADS-B original message, and calculate target information according to an ADS-B standard protocol, including: position, altitude, speed information.

Counting all received aircraft message information, and sequencing the aircraft according to the message updating frequency of the aircraft, the distance between the aircraft position and the target point, the speed of the aircraft or the flight height information of the aircraft.

Message information statistics are the classification or ranking of aircraft in multiple dimensions. The method comprises the steps of firstly receiving aircraft message information for more than 15s on the satellite, accumulating enough message information as samples, classifying the information of the same aircraft according to flight call signs of the aircraft by the samples, and sorting the samples according to message update frequency of the messages, distance between the aircraft position and a target point, speed of the aircraft or flight height of the aircraft respectively to form a sorting table.

The guiding information output instruction has two types, one is to set a satellite to search according to the flight call sign of the aircraft, so as to realize the tracking of the specified aircraft; and the other is to screen according to the sorting table, and select one aircraft with highest updating frequency, nearest aircraft position, fastest aircraft speed or highest flying height from the selected aircraft to search.

And fifthly, the ADS-B receiving processor eliminates the outlier in the message, and the ADS-B receiving processor sends the guiding information to the attitude and orbit control subsystem through the RS422 interface.

The on-orbit presence field value of the civil aviation passenger plane message received by the ADS-B: the ADS-B may receive the aircraft message with stronger energy outside the field of view; the civil aircraft messages may have large position jumps. The following outlier rejection scheme was employed:

1) Out-of-view aircraft rejection:

and removing the aircraft which deviates too far from the field of view by adopting a judging method based on distance constraint. Firstly, by the ground surface filling instruction, the longitude and latitude (L ₀,B₀) of the center point of the task are defined, and the longitude L _i and the latitude B _i in the message meet the following conditions at the same time, the message is considered to be the message in the field of view,

If the target library is not in the range of the formula, the target library to be tracked is not put in, but is still downloaded through the data transmission channel.

2) And removing interference messages with overlarge position jump:

and eliminating abnormal aircraft messages with too fast position jump by adopting a speed constraint criterion.

In order to prevent the jump phenomenon of the airplane message from affecting tracking, the 3 Mach (1020 m/s) flight speed is taken as a threshold value, and a round of jump judgment is carried out on the guiding information to be output. The judging method comprises the following steps:

The time, longitude, and latitude (t _i,L_i,B_i,H_i) of the latest guidance information are different from the time, longitude, and latitude (t _i-1,L_i-1,B_i-1,H_i-1) of the last beat, and the flying speed V is obtained.

Wherein, the units of longitude and latitude are radians,

If V is not less than 1020m/s, the guiding information 'update state' is set to 0xF1: the presence of a jump in the guidance information,

After the wild value is removed, the safety of the guide information can be enhanced, the transmission frequency of the guide information is 1Hz, and the guide information is consistent with the broadcasting frequency of the ADS-B message.

And step six, the attitude and orbit control subsystem receives the guide information, accumulates more than 5 beats of effective guide information, then carries out track fitting, and continuously updates the fitted track by using the latest 5 beats of guide information.

The track fitting is carried out by combining a position message and a speed message, firstly, more than 5 aircraft position points are utilized to deduce a first-order item and a second-order item of the flight track, the aircraft speed is used for restraining, and the second-order item is corrected.

Wherein the time matrix T is calculated as follows

And seventhly, performing attitude control according to the fitted track, enabling the satellite to point to the airplane, and informing the satellite comprehensive electronic subsystem after the attitude control subsystem controls the satellite to point in place.

The camera imaging instruction is sent after being judged according to the satellite tracking state, so that imaging is started after tracking is completed, and imaging is not performed in the process of rapidly pointing to the target.

The application also provides a satellite-to-civil aircraft tracking imaging system which can be realized by executing the flow steps of the satellite-to-civil aircraft tracking imaging method, namely, the satellite-to-civil aircraft tracking imaging method can be understood as a preferred implementation mode of the satellite-to-civil aircraft tracking imaging system by a person skilled in the art. Comprising the following steps:

Those skilled in the art will appreciate that the application provides a system and its individual devices, modules, units, etc. that can be implemented entirely by logic programming of method steps, in addition to being implemented as pure computer readable program code, in the form of logic gates, switches, application specific integrated circuits, programmable logic controllers, embedded microcontrollers, etc. Therefore, the system and various devices, modules and units thereof provided by the application can be regarded as a hardware component, and the devices, modules and units for realizing various functions included in the system can also be regarded as structures in the hardware component; means, modules, and units for implementing the various functions may also be considered as either software modules for implementing the methods or structures within hardware components.

The foregoing describes specific embodiments of the present application. It is to be understood that the application is not limited to the particular embodiments described above, and that various changes or modifications may be made by those skilled in the art within the scope of the appended claims without affecting the spirit of the application. The embodiments of the application and the features of the embodiments may be combined with each other arbitrarily without conflict.

Claims

1. A satellite-to-civil aircraft tracking imaging method, comprising:

2. The method of tracking and imaging a satellite to a civil aircraft according to claim 1, wherein the message reception in step one includes antenna reception, radio frequency signal processing and digital information processing;

The radio frequency signal processing is to filter, amplify and analog-to-digital convert an ADS-B radio frequency signal received by an antenna to form a sampling signal;

the digital information processing is to process the original sampling signal, including: demodulation, header detection, time management processing, extracting effective ADS-B message in signal and noise.

3. The method for tracking and imaging a civil aircraft by using a satellite according to claim 1, wherein the step two of ADS-B message parsing decodes an ADS-B original message, and calculates target information according to ADS-B standard protocol, including: position, altitude, speed information.

4. The method of satellite-to-civil aircraft tracking imaging of claim 1 wherein the message statistics in step three are classifying or ranking aircraft in multiple dimensions;

5. The method of tracking and imaging a civil aircraft with a satellite according to claim 1, wherein the guidance information output instruction in the fourth step includes two types:

6. The method for tracking and imaging a civil aircraft by using a satellite according to claim 1, wherein the outlier rejection in the fifth step includes out-of-view aircraft rejection and interference message rejection with excessive position jump;

wherein, the units of longitude and latitude are radians,

7. The method for tracking and imaging a civil aircraft by using a satellite according to claim 1, wherein the security of the guiding information is enhanced after the wild value is removed, and the sending frequency of the guiding information is 1Hz and is consistent with the broadcasting frequency of the ADS-B message.

8. The method for tracking and imaging a civil aircraft by using satellites according to claim 1, wherein in the sixth step, the track fitting is performed by combining a position message and a speed message, first-order items and second-order items of a flight track are deduced by using more than 5 aircraft position points, and the second-order items are corrected by restraining the aircraft speed; the calculation formula is as follows:

Wherein, the time matrix T is calculated as follows:

9. The method for tracking and imaging a civil aircraft by using a satellite according to claim 1, wherein the camera imaging instruction in the step eight is sent after the satellite tracking state is determined, so that the imaging is started after the tracking is completed without imaging during the process of rapidly pointing to the target.

10. A satellite-to-civil aircraft tracking imaging system, comprising: