An airborne platform monitoring method and system for NGSO constellation system ground terminals

Abstract

The application discloses an air platform monitoring method and system for a ground terminal of an NGSO constellation system, and an air platform receiver system stays at a certain position in the air for a certain time, waits for a ground terminal signal to arrive beyond a threshold of the air platform receiver system, and determines whether a ground terminal exists in an antenna coverage area of the air platform receiver system. If no signal beyond the threshold exists, the air platform receiver system moves to a next area. If the signal beyond the threshold exists, the height of the air platform receiver system is reduced, and the air platform receiver system is searched again in the coverage area until the terminal is found.

Description

Technical Field

[0001] This invention belongs to the field of satellite communication and radio propagation technology, specifically relating to an airborne platform monitoring method and system for ground terminals of an NGSO constellation system. Background Technology

[0002] In recent years, the continuously developing Non-Geostationary Satellite Orbit (NGSO) constellation systems operate in the Ku / Ka / Q / V frequency bands, with constellations reaching tens of thousands of satellites. They also use Low Earth Orbit (LEO), where each satellite in the system is constantly moving relative to the Earth, resulting in ground terminals pointing towards the sky and their pointing direction changing rapidly.

[0003] With the rapid development of the NGSO constellation system, the application of ground terminals will become increasingly widespread, potentially causing harmful interference to other systems operating on the same or adjacent frequencies. Therefore, it is necessary to conduct radio monitoring and locating of ground terminals. Since ground terminals communicate with NGSO satellites, they often use Ku and higher frequency bands. Ground terminal antennas have narrow main lobe beams, strong directivity, are variable in real time, and point upwards, making it difficult for ground monitoring equipment to effectively receive terminal signals. Therefore, using an aerial platform for radio monitoring and locating terminal signals is a feasible method. Aerial platforms achieve signal monitoring within a certain area by mounting signal receiving equipment on platforms such as UAVs or hot air balloons. Currently, there is no mature aerial platform system available for NGSO satellite ground terminals, and methods for monitoring NGSO satellite ground terminals using aerial platforms are also lacking. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to provide an airborne platform monitoring method and system for NGSO constellation system ground terminals, which addresses the shortcomings of the prior art and solves the technical problem that the specific location of the interference source cannot be determined when the NGSO ground terminal interferes with other systems.

[0005] The present invention adopts the following technical solution:

[0006] A method for monitoring ground terminals of an NGSO constellation system using an airborne platform includes the following steps:

[0007] S1. Establish an air platform receiver system model based on the air platform receiver system parameters, and determine the air platform altitude based on the air platform receiver characteristics. Calculate the signal threshold of the air platform receiver system;

[0008] S2. Establish a ground terminal model based on the ground terminal parameters of the NGSO constellation system;

[0009] S3. Based on the NGSO constellation system corresponding to the ground terminal communication, determine the orbital parameters of each satellite in the NGSO constellation system, establish the orbital model of the NGSO constellation system, and calculate the simulation start time for all satellites in the NGSO constellation system. Until the simulation ends Each time point within Location data, time interval is Second;

[0010] S4. Based on the location data obtained in step S3, and combined with the satellite tracking method of the ground terminal, calculate the location of the ground terminal in... arrive Every moment within the time period azimuth and pitch angle The data is then used to represent the pointing data at each time step using a unit vector;

[0011] S5. Based on the ground terminal model obtained in step S2 and the pitch angle obtained in step S4... Data determines the minimum elevation angle of the actual communication terminal. The half-power beam ground arrival angle is determined based on the air platform receiver system parameters obtained in step S1. Take the lowest ground angle of arrival of the beam in the coverage area of ​​the air platform. ;

[0012] S6. Taking the ground terminal as the origin, based on the aerial platform height obtained in step S1... and the lowest ground arrival angle of the coverage area beam obtained in step S5 Determine the coverage radius of the main beam. and coverage area S;

[0013] S7. Based on the main beam coverage radius obtained in step S6 The cumulative distribution of hovering latency of the aerial platform was calculated over the coverage area S. ;

[0014] S8, The altitude obtained by the air platform receiver system in step S1 The cumulative distribution of hovering waiting time obtained in hovering step S7 If the signal threshold obtained in step S1 is exceeded, a ground terminal exists within the coverage area.

[0015] Specifically, in step S1, the air platform receiver system parameters include system noise temperature, maximum antenna gain, antenna pattern, and beamwidth, based on the signal-to-noise ratio threshold of the receiving terminal signal. Determine the minimum power that the terminal can receive. as follows:

[0016]

[0017] in, This represents the background noise power of the airborne platform receiver.

[0018] Specifically, in step S2, the NGSO constellation system ground terminal transmit power for:

[0019]

[0020] in, For ground terminals in Internal transmission power, For bandwidth.

[0021] Specifically, in step S3, the orbital parameters of each satellite in the constellation include orbital inclination, right ascension of the ascending node, mean anomaly, argument of perigee, eccentricity, and semi-major axis. This information is used to model the satellite constellation system's orbit and calculate the simulation start time for all satellites within the constellation system. Until the simulation ends Each time point within The position, the time interval is Second.

[0022] Specifically, in step S5, the lowest ground arrival angle of the beam in the coverage area of ​​the airborne platform. for:

[0023]

[0024] Specifically, in step S6, the origin is taken as the ground terminal. This is the initial azimuth angle from the ground terminal to the air platform. This refers to the azimuth angle of the ground terminal looking at the air platform, where the distance between the ground terminal and the air platform is a fixed value. Determine path loss The airborne platform receiver system remains stationary, traversing the ground terminals along the edge of the coverage area S to obtain the coverage area S of the airborne platform receiver system and the main beam coverage radius. for:

[0025]

[0026] in, The elevation angle is the direction of the aerial platform. The altitude of the aerial platform.

[0027] Specifically, step S7 is as follows:

[0028] S701, Determine the orientation vector of the airborne platform. Calculate the gain of the terminal antenna in that direction at each moment based on the terminal antenna pattern. ;

[0029] S702. Based on the propagation characteristics of radio signals, calculate the power received from the ground terminal to the air platform at each moment. and signal-to-noise ratio ;

[0030] S703, Traverse the time and record... At that moment, Duration of time If Seconds later and ,but , indicating in Waiting is always necessary It will take several seconds to receive a valid signal from the ground terminal;

[0031] S704, , For azimuth traversal step, if Repeat steps S701 to S703; otherwise, proceed to the next step.

[0032] S705, According to the length of stay The cumulative distribution of stay time was obtained through statistical calculation. .

[0033] Furthermore, in step S702, the ground terminal receives power from the power receiver at each time point. and signal-to-noise ratio Specifically:

[0034]

[0035]

[0036] in, For ground terminal transmission power, For free space loss, To monitor the maximum gain of the antenna, This represents the background noise power of the airborne platform receiver system.

[0037] Specifically, in step S8, if the signal threshold of the receiving system obtained in step S1 is exceeded, and there is a ground terminal in the coverage area, the altitude H is reduced or an air platform antenna with a narrower main lobe width is selected, and steps S6 to S8 are repeated until the ground terminal is found.

[0038] Secondly, embodiments of the present invention provide an airborne platform monitoring system for an NGSO constellation system ground terminal, comprising:

[0039] The threshold module establishes an air platform receiver system model based on the air platform receiver system parameters and calculates the signal threshold of the air platform receiver system.

[0040] The terminal module establishes a ground terminal model based on the ground terminal parameters of the NGSO constellation system.

[0041] The location module determines the orbital parameters of each satellite in the NGSO constellation system based on the ground terminal communication, establishes the orbital model of the NGSO constellation system, and calculates the simulation start time for all satellites within the NGSO constellation system. Until the simulation ends Each time point within Location data, time interval is Second;

[0042] The vector module, based on the position data obtained from the position module and combined with the satellite tracking method of the ground terminal, calculates the position of the ground terminal. arrive Every moment within the time period azimuth and pitch angle The data is then used to represent the pointing data at each time step using a unit vector;

[0043] The angle module uses the ground terminal model obtained from the terminal module and the pitch angle obtained from the vector module. Data determines the minimum elevation angle of the actual communication terminal. The half-power beam ground arrival angle is determined based on the air platform receiver system parameters obtained from the threshold module. Take the lowest ground angle of arrival of the beam in the coverage area of ​​the air platform. ;

[0044] The area module, with the ground terminal as the origin, uses the aerial platform height obtained from the threshold module. and the lowest ground arrival angle of the coverage area beam obtained by the angle module. Determine the coverage radius of the main beam. and coverage area S;

[0045] The time module, based on the main beam coverage radius obtained from the region module. The cumulative distribution of hovering latency of the aerial platform was calculated over the coverage area S. ;

[0046] The monitoring module and the aerial platform receiver system obtain the altitude from the threshold module. The cumulative distribution of hovering wait time obtained from the hovering time module If the signal exceeds the threshold obtained by the threshold module, a ground terminal exists within the coverage area.

[0047] Compared with the prior art, the present invention has at least the following beneficial effects:

[0048] An aerial platform monitoring method for ground terminals of an NGSO constellation system is proposed. By combining statistical results from simulation analysis, the required hovering time is determined, providing a deterministic and feasible monitoring strategy and system for monitoring and locating ground terminals.

[0049] Furthermore, the aerial platform monitoring receiver needs to specify parameters such as noise temperature, antenna pattern, and signal-to-noise ratio threshold in order to calculate whether the signal from the ground terminal to the monitoring receiver can be detected using the aerial platform hovering monitoring mode.

[0050] Furthermore, the NGSO constellation system ground terminal transmit power It needs to be converted to power within the same bandwidth as the noise in order to calculate the signal-to-noise ratio.

[0051] Furthermore, the orbital parameters for each satellite in the constellation need to be specified, including orbital inclination, right ascension of the ascending node, mean anomaly, argument of perigee, eccentricity, and semi-major axis, as well as the orbital element. The simulation start time for the positions of all satellites within the constellation system also needs to be specified. Simulation end time and simulation time interval seconds, time interval The shorter the simulation time, the longer the simulation duration, the more satellite position data is calculated, which means more ground terminal pointing data, and the more accurate the statistical analysis of hovering time.

[0052] Furthermore, the lowest ground angle of arrival of the beam in the coverage area of ​​the airborne platform. The minimum communication angle for actual ground terminals and half-power beam arrival angle A larger value can be used to determine whether the main beam transmitted by the ground terminal can be pointed in the direction of the main beam received by the launch platform, thus eliminating the possibility that the ground terminal is located in an area where it cannot be pointed at the launch platform, and reducing the hovering monitoring waiting time.

[0053] Furthermore, the average time required for the edge of coverage area S to point to the launch platform is greater than the time required inside coverage area S. That is, when the terminal is at the edge of coverage area S, the hovering waiting time monitored by the launch platform is greater than the hovering time of the ground terminal inside coverage area S. In other words, whether the waiting time required to hover at the edge receives a signal greater than the threshold can determine whether there is a ground terminal inside the entire area S.

[0054] Furthermore, traversing the edge of the coverage area S can increase the ground terminal pointing data, improve the accuracy of statistical calculations, and eliminate inaccurate hovering waiting time caused by the regular pointing of ground terminals under special circumstances.

[0055] Furthermore, the cumulative distribution of hovering time required for all times and all edge regions is obtained, including calculating the signal-to-noise ratio (SNR) transmitted from the ground terminal to the airborne platform receiver for each time interval during the simulation time when the ground terminal is at different positions on the S-edge, and the duration for which the SNR is greater than the threshold.

[0056] Furthermore, if a signal exceeding the threshold is detected during the hovering time, a smaller monitoring coverage area S can be obtained by lowering the altitude H or selecting an aerial platform antenna with a narrower main lobe width, making it easier to detect ground terminals.

[0057] It is understandable that the beneficial effects of the second aspect mentioned above can be found in the relevant descriptions in the first aspect mentioned above, and will not be repeated here.

[0058] In summary, this invention can effectively monitor uplink signals of ground terminals within the coverage area of ​​an aerial platform antenna; by calculating hovering time, different hovering times can be selected according to actual needs during monitoring; and based on the aerial platform hovering monitoring strategy, ground terminals within a smaller area can be identified by lowering the altitude or changing the antenna.

[0059] The technical solution of the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. Attached Figure Description

[0060] Figure 1 A flowchart for calculating the dwell time of an aerial platform;

[0061] Figure 2 A schematic diagram showing the azimuth traversal of the aerial platform in different directions from the ground terminal;

[0062] Figure 3 An equivalent schematic diagram for azimuth traversal of ground terminals;

[0063] Figure 4 This is a schematic diagram of the hovering monitoring method for an aerial platform according to the present invention. Detailed Implementation

[0064] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0065] In the description of this invention, it should be understood that the terms "comprising" and "including" indicate the presence of the described features, integrals, steps, operations, elements and / or components, but do not exclude the presence or addition of one or more other features, integrals, steps, operations, elements, components and / or collections thereof.

[0066] It should also be understood that the terminology used in this specification is for the purpose of describing particular embodiments only and is not intended to limit the invention. As used in this specification and the appended claims, the singular forms “a,” “an,” and “the” are intended to include the plural forms unless the context clearly indicates otherwise.

[0067] It should also be further understood that the term "and / or" as used in this specification and the appended claims refers to any combination and all possible combinations of one or more of the associated listed items, and includes such combinations. For example, A and / or B can represent three cases: A alone, A and B simultaneously, and B alone. Additionally, the character " / " in this document generally indicates that the preceding and following objects have an "or" relationship.

[0068] It should be understood that although terms such as first, second, third, etc., may be used in the embodiments of the present invention to describe the preset range, these preset ranges should not be limited to these terms. These terms are only used to distinguish the preset ranges from one another. For example, without departing from the scope of the embodiments of the present invention, the first preset range may also be referred to as the second preset range, and similarly, the second preset range may also be referred to as the first preset range.

[0069] Depending on the context, the word "if" as used here can be interpreted as "when," "when," "in response to determination," or "in response to detection." Similarly, depending on the context, the phrase "if determination" or "if detection (of the stated condition or event)" can be interpreted as "when determination," "in response to determination," "when detection (of the stated condition or event)," or "in response to detection (of the stated condition or event)."

[0070] The accompanying drawings illustrate various structural schematic diagrams according to embodiments disclosed in this invention. These drawings are not to scale, and some details have been enlarged for clarity, and some details may have been omitted. The shapes of the various regions and layers shown in the drawings, as well as their relative sizes and positional relationships, are merely exemplary and may deviate from reality due to manufacturing tolerances or technical limitations. Furthermore, those skilled in the art can design regions / layers with different shapes, sizes, and relative positions as needed.

[0071] This invention provides an airborne platform monitoring method for ground terminals in an NGSO constellation system. The airborne platform receiver system hovers at a certain position in the air for a certain period of time, waiting for the ground terminal signal to exceed a threshold of the airborne platform receiver system. It then determines whether a ground terminal exists within the antenna coverage area of ​​the airborne platform receiver system. By calculating the cumulative distribution of the time required for the airborne platform receiver system to detect the ground terminal, the hovering time under different time probabilities is obtained. The hovering time guides the monitoring strategy of the airborne platform receiver system. If a signal exceeding the threshold is detected within the hovering time, the system lowers its altitude to conduct a more refined search within the coverage area until the terminal is found. If no signal exceeding the threshold is found, the airborne platform receiver system moves to the next area for search.

[0072] Please see Figure 1 and Figure 4 The present invention discloses an airborne platform monitoring method for a ground terminal of an NGSO constellation system, comprising the following steps:

[0073] S1. Determine the parameters of the airborne platform receiver system, including system noise temperature, maximum antenna gain, antenna pattern, and beamwidth; establish a receiver system model; and determine the altitude of the airborne platform receiver system. Generally, the higher the platform, the larger the monitoring coverage area, and the signal threshold of the receiving system is calculated;

[0074] Determine the noise temperature of the aerial platform system And antenna gain, maximum antenna gain Beamwidth Parameters for calculating the background noise power of the airborne platform receiver system. To facilitate comparison with the received signal power, a background noise power with a bandwidth of 1Hz was selected. The frequency is set to 1Hz, based on the signal-to-noise ratio threshold of the receiving terminal. Determine the minimum power that the terminal can receive. as follows:

[0075]

[0076]

[0077] in, Let be the Boltzmann constant, with a value of .

[0078] This invention is used for signal monitoring and setting. If used for signal recognition, It needs to be greater than 10dB.

[0079] S2. Determine the NGSO constellation system ground terminal transmit power, antenna gain, antenna size, operating frequency, and minimum signal angle. Parameters are used to establish a ground terminal model;

[0080] Determine the type and location of the NGSO ground terminal and obtain its operating frequency. ,bandwidth ground terminal transmission power Antenna maximum gain Antenna pattern, antenna aperture Polarization mode, beamwidth Minimum working elevation angle wait.

[0081]

[0082] S3. Based on the NGSO constellation system corresponding to the ground terminal communication, determine the orbital parameters of each satellite in the constellation, including orbital inclination, right ascension of the ascending node, mean anomaly, argument of perigee, eccentricity, and semi-major axis. Establish the orbital model of the constellation system and calculate the simulation start time for all satellites in the constellation system. Until the simulation ends Each time point within The position, the time interval is Second;

[0083] Simulation time interval The smaller the value, the longer the simulation time. The longer the length, the more accurate the final cumulative distribution result will be.

[0084] S4. Based on the satellite position data from step S3 and the satellite tracking method of the ground terminal, calculate the position of the ground terminal in... arrive Every moment within the time period azimuth and pitch angle Data (pointing to data), and converting the pointing data at each time step into a unit vector ( , )express;

[0085] The satellite tracking method generally includes the longest communication time, the shortest communication distance, and the highest communication angle. The specific satellite tracking method is determined by the system.

[0086] S5. Determine the minimum elevation angle of the actual communication terminal based on the elevation angle data in step S4. The half-power beam ground arrival angle is determined based on the air platform receiving antenna pattern in step S1. Take the lowest ground angle of arrival of the beam in the coverage area of ​​the air platform. ;

[0087] Half-power beam ground arrival angle for:

[0088]

[0089] in, This is the half-power beamwidth.

[0090] S6 Taking the ground terminal as the origin, based on the aerial platform height in step S2 The lowest ground arrival angle of the coverage area beam in step S5 Determine the main beam coverage radius of the airborne platform. and coverage area S;

[0091] Main beam coverage radius for:

[0092]

[0093] With the ground terminal as the origin, The elevation angle is the direction of the aerial platform. The height of the aerial platform. This is the initial azimuth angle from the ground terminal to the air platform. This refers to the azimuth angle of the ground terminal looking at the air platform, where the distance between the ground terminal and the air platform is a fixed value. The path loss is determined regardless of the azimuth angle. ;

[0094]

[0095] The ground terminal remains stationary, and the airborne platform remains stationary as it traverses the edge of the coverage area S, visiting the ground terminal as follows: Figure 2 and Figure 3 As shown, the coverage area S of the aerial platform can be obtained in this way. The hovering time required for terminal monitoring at the edge of area S is greater than the time inside area S. Therefore, the hovering time is calculated based on the result of the terminal being located at the edge of area S.

[0096] S7. Calculate the cumulative distribution of hovering time for aerial platforms. ;

[0097] S701, Determine the orientation vector of the airborne platform. Calculate the gain of the terminal antenna in that direction at each moment based on the terminal antenna pattern. ;

[0098] S702. Based on the propagation characteristics of radio signals, calculate the received power from the ground terminal to the air platform at each moment. and signal-to-noise ratio ;

[0099]

[0100]

[0101] S703, Traverse the time and record... At that moment, Duration of time If Seconds later and ,but , indicating in Waiting is always necessary It will take several seconds to receive a valid signal from the ground terminal;

[0102] The azimuth angle of the empty platform relative to the ground terminal was obtained by iterating through the time. The hovering time required at each moment.

[0103] S704, , For azimuth traversal step, if Repeat steps S701 to S703; otherwise, proceed to the next step.

[0104] The hovering time within a circumference of the edge of region S is obtained by traversing the azimuth angle of the launch platform relative to the ground terminal.

[0105] S705, According to the length of stay The cumulative distribution of stay time was obtained through statistical calculation. This refers to the hovering monitoring time required under different cumulative time probabilities, thus obtaining the required monitoring hovering time for the aerial platform under different probabilities.

[0106] S8, Height in step S1 Lower hover If no signal exceeding the threshold in step S1 is detected, it indicates that there are no ground terminals in the coverage area (accuracy). The mobile aerial platform will hover and monitor the next area. If a signal exceeding the threshold is detected, it indicates that there may be a ground terminal in that area.

[0107] S9. When the area S in step S6 exceeds the set value, re-search within area S: reduce the altitude H or select an air platform antenna with a narrower main lobe width, and repeat steps S6 to S8 until the ground terminal is found.

[0108] In another embodiment of the present invention, an airborne platform monitoring system for NGSO constellation ground terminals is provided. This system can be used to implement the above-mentioned airborne platform monitoring method for NGSO constellation ground terminals. Specifically, the airborne platform monitoring system for NGSO constellation ground terminals includes a threshold module, a terminal module, a position module, a vector module, an angle module, a region module, a time module, and a monitoring module.

[0109] The threshold module establishes an air platform receiver system model based on the air platform receiver system parameters and determines the air platform altitude according to the characteristics of the air platform receiver. Calculate the signal threshold of the air platform receiver system;

[0110] The terminal module establishes a ground terminal model based on the ground terminal parameters of the NGSO constellation system.

[0111] The location module determines the orbital parameters of each satellite in the NGSO constellation system based on the ground terminal communication, establishes the orbital model of the NGSO constellation system, and calculates the simulation start time for all satellites within the NGSO constellation system. Until the simulation ends Each time point within Location data, time interval is Second;

[0112] The vector module, based on the ground terminal model obtained from the terminal module and the position data obtained from the position module, and combined with the ground terminal's satellite tracking method, calculates the ground terminal's position in... arrive Every moment within the time period azimuth and pitch angle The data is then used to represent the pointing data at each time step using a unit vector;

[0113] The angle module, based on the pitch angle obtained from the vector module. Data determines the minimum elevation angle of the actual communication terminal. The half-power beam ground arrival angle is determined based on the air platform receiver system parameters obtained from the threshold module. Take the lowest ground angle of arrival of the beam in the coverage area of ​​the air platform. ;

[0114] The area module, with the ground terminal as the origin, uses the aerial platform height obtained from the threshold module. and the lowest ground arrival angle of the coverage area beam obtained by the angle module. Determine the coverage radius of the main beam. and coverage area S;

[0115] The time module, based on the main beam coverage radius obtained from the region module. The cumulative distribution of hovering latency of the aerial platform was calculated over the coverage area S. ;

[0116] The monitoring module and the aerial platform receiver system obtain the altitude from the threshold module. The cumulative distribution of hovering wait time obtained from the hovering time module If the signal exceeds the threshold obtained by the threshold module, a ground terminal exists within the coverage area.

[0117] In another embodiment of the present invention, a terminal device is provided, comprising a processor and a memory. The memory stores a computer program, which includes program instructions. The processor executes the program instructions stored in the computer storage medium. The processor may be a Central Processing Unit (CPU), or other general-purpose processors, digital signal processors (DSPs), application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. It is the computing and control core of the terminal, suitable for implementing one or more instructions, specifically suitable for loading and executing one or more instructions to achieve a corresponding method flow or corresponding function. The processor described in this embodiment of the present invention can be used in the operation of an airborne platform monitoring method for a ground terminal of an NGSO constellation system, including:

[0118] An air platform receiver system model is established based on the air platform receiver system parameters, and the air platform altitude is determined based on the air platform receiver characteristics. The simulation process involves: calculating the signal threshold of the airborne platform receiver system; establishing a ground terminal model based on the ground terminal parameters of the NGSO constellation system; determining the orbital parameters of each satellite in the NGSO constellation system based on the NGSO constellation system corresponding to the ground terminal communication, establishing the orbital model of the NGSO constellation system, and calculating the simulation start time for all satellites in the NGSO constellation system. Until the simulation ends Each time point within Location data, time interval is Seconds; based on location data and the satellite tracking method of the ground terminal, calculate the time at which the ground terminal is... arrive Every moment within the time period azimuth and pitch angle The data is processed, and the pointing data at each moment is represented by a unit vector; based on the ground terminal model and pitch angle... Data determines the minimum elevation angle of the actual communication terminal. The half-power beam ground arrival angle is determined based on the airborne platform receiver system parameters. Take the lowest ground angle of arrival of the beam in the coverage area of ​​the air platform. Taking the ground terminal as the origin, based on the height of the aerial platform... and the lowest ground angle of arrival of the beam in the coverage area Determine the coverage radius of the main beam. And the coverage area S; calculate the cumulative distribution of hovering latency of the aerial platform. The airborne platform receiver system is at high altitude. Hovering wait time cumulative distribution results If the signal threshold is exceeded, a ground terminal is present in the coverage area.

[0119] In another embodiment of the present invention, a storage medium is provided, specifically a computer-readable storage medium (Memory). This computer-readable storage medium is a memory device in a terminal device used to store programs and data. It is understood that the computer-readable storage medium here can include both the built-in storage medium in the terminal device and extended storage media supported by the terminal device. The computer-readable storage medium provides storage space that stores the terminal's operating system. Furthermore, this storage space also stores one or more instructions suitable for loading and execution by a processor. These instructions can be one or more computer programs (including program code). It should be noted that the computer-readable storage medium here can be high-speed RAM or non-volatile memory, such as at least one disk storage device.

[0120] One or more instructions stored in a computer-readable storage medium can be loaded and executed by a processor to implement the corresponding steps of the airborne platform monitoring method for the NGSO constellation system ground terminal in the above embodiments; one or more instructions in the computer-readable storage medium are loaded and executed by the processor in the following steps:

[0121] An air platform receiver system model is established based on the air platform receiver system parameters, and the air platform altitude is determined based on the air platform receiver characteristics. The simulation process involves: calculating the signal threshold of the airborne platform receiver system; establishing a ground terminal model based on the ground terminal parameters of the NGSO constellation system; determining the orbital parameters of each satellite in the NGSO constellation system based on the NGSO constellation system corresponding to the ground terminal communication, establishing the orbital model of the NGSO constellation system, and calculating the simulation start time for all satellites in the NGSO constellation system. Until the simulation ends Each time point within Location data, time interval is Seconds; based on location data and the satellite tracking method of the ground terminal, calculate the time at which the ground terminal is... arrive Every moment within the time period azimuth and pitch angle The data is processed, and the pointing data at each moment is represented by a unit vector; based on the ground terminal model and pitch angle... Data determines the minimum elevation angle of the actual communication terminal. The half-power beam ground arrival angle is determined based on the airborne platform receiver system parameters. Take the lowest ground angle of arrival of the beam in the coverage area of ​​the air platform. Taking the ground terminal as the origin, based on the height of the aerial platform... and the lowest ground angle of arrival of the beam in the coverage area Determine the coverage radius of the main beam. And the coverage area S; calculate the cumulative distribution of hovering latency of the aerial platform. The airborne platform receiver system is at high altitude. Hovering wait time cumulative distribution results If the signal threshold is exceeded, a ground terminal is present in the coverage area.

[0122] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. The components of the embodiments of the present invention described and shown in the accompanying drawings can generally be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort are within the scope of protection of the present invention.

[0123] Example:

[0124] This embodiment provides an example of a monitoring method for an airborne platform to monitor the ground terminal of an NGSO constellation system. The orbital parameters, ground terminal parameters, and airborne platform parameters of the NGSO constellation system are shown in Table 1 below:

[0125] Table 1. Simulation or experimental data or specific application examples of NGSO constellation system ground terminal hovering monitoring parameters.

[0126]

[0127] Based on the parameters in Table 1, the advantages and benefits of the present invention are further discussed using data. Figure 1 The process was followed to obtain the hover time calculation results, as shown in Table 2:

[0128]

[0129] When using an omnidirectional antenna on an airborne platform, if a ground terminal exists within the coverage area, the probability of detecting the ground terminal within 168 seconds is 90%, within 191 seconds is 95%, and within 210 seconds is 98%. To rule out the possibility that no ground terminal exists in the area, the platform needs to hover for 277 seconds.

[0130] When using a directional antenna on an airborne platform, if a ground terminal exists within the coverage area, the probability of detecting the ground terminal within 5 seconds is 90%, within 10 seconds is 95%, and within 17 seconds is 98%. To rule out the possibility that no ground terminal exists in the area, the antenna needs to hover for 51 seconds.

[0131] Monitoring strategies can be developed based on the results of the examples: using omnidirectional antennas or large-area searches, and then using directional antennas or reducing the platform height to conduct small-area searches after receiving a signal, can improve search efficiency.

[0132] In summary, this invention provides a method and system for monitoring airborne platforms of NGSO constellation ground terminals. This method can efficiently monitor and locate NGSO constellation ground terminals. The provided hovering time calculation method can effectively estimate the time required for a ground terminal signal to point to an airborne platform, avoiding disorderly and blind monitoring. Combined with the coverage area of ​​the monitoring antenna, feasible and efficient monitoring strategies can be formulated.

[0133] Those skilled in the art will clearly understand that, for the sake of convenience and brevity, the above-described division of functional units and modules is merely an example. In practical applications, the above functions can be assigned to different functional units and modules as needed, that is, the internal structure of the device can be divided into different functional units or modules to complete all or part of the functions described above. The functional units and modules in the embodiments can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. The integrated unit can be implemented in hardware or as a software functional unit. Furthermore, the specific names of the functional units and modules are only for easy differentiation and are not intended to limit the scope of protection of this application. The specific working process of the units and modules in the above system can be referred to the corresponding process in the foregoing method embodiments, and will not be repeated here.

[0134] In the above embodiments, the descriptions of each embodiment have different focuses. For parts that are not described in detail or recorded in a certain embodiment, please refer to the relevant descriptions of other embodiments.

[0135] Those skilled in the art will recognize that the units and algorithm steps of the various examples described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are implemented in hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementations should not be considered beyond the scope of this invention.

[0136] In the embodiments provided by this invention, it should be understood that the disclosed devices / terminals and methods can be implemented in other ways. For example, the device / terminal embodiments described above are merely illustrative. For instance, the division of modules or units is only a logical functional division, and in actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the coupling or direct coupling or communication connection shown or discussed may be through some interfaces; the indirect coupling or communication connection between devices or units may be electrical, mechanical, or other forms.

[0137] The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the units can be selected to achieve the purpose of this embodiment according to actual needs.

[0138] Furthermore, the functional units in the various embodiments of the present invention can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. The integrated unit can be implemented in hardware or as a software functional unit.

[0139] If the integrated module / unit is implemented as a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, all or part of the processes in the methods of the above embodiments can also be implemented by a computer program instructing related hardware. The computer program can be stored in a computer-readable storage medium, and when executed by a processor, it can implement the steps of the various method embodiments described above. The computer program includes computer program code, which can be in the form of source code, object code, executable files, or certain intermediate forms. The computer-readable medium can include: any entity or device capable of carrying the computer program code, a recording medium, a USB flash drive, a portable hard drive, a magnetic disk, an optical disk, a computer memory, or a read-only memory (ROM). Computer-readable media may include only memory (ROM), random access memory (RAM), electrical carrier signals, telecommunication signals, and software distribution media, etc. It should be noted that the content of the computer-readable media may be appropriately increased or decreased according to the requirements of legislation and patent practice in the jurisdiction. For example, in some jurisdictions, according to legislation and patent practice, computer-readable media may not include electrical carrier signals and telecommunication signals.

[0140] This application is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of this application. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart... Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0141] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0142] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0143] The above content is only for illustrating the technical concept of the present invention and should not be construed as limiting the scope of protection of the present invention. Any modifications made to the technical solution based on the technical concept proposed in this invention shall fall within the scope of protection of the claims of this invention.

Claims

1. A method for monitoring an airborne platform for a ground terminal in an NGSO constellation system, characterized in that, Includes the following steps: S1. Establish an air platform receiver system model based on the air platform receiver system parameters, and determine the air platform altitude based on the air platform receiver characteristics. Calculate the signal threshold of the air platform receiver system; S2. Establish a ground terminal model based on the ground terminal parameters of the NGSO constellation system; S3. Based on the NGSO constellation system corresponding to the ground terminal communication, determine the orbital parameters of each satellite in the NGSO constellation system, establish the orbital model of the NGSO constellation system, and calculate the simulation start time for all satellites in the NGSO constellation system. Until the simulation ends Each time point within Location data, time interval is Second; S4. Based on the location data obtained in step S3, and combined with the satellite tracking method of the ground terminal, calculate the location of the ground terminal in... arrive Every moment within the time period azimuth and pitch angle The data is then used to represent the pointing data at each time step using a unit vector; S5. Based on the ground terminal model obtained in step S2 and the pitch angle obtained in step S4... Data determines the minimum elevation angle of the actual communication terminal. The half-power beam ground arrival angle is determined based on the air platform receiver system parameters obtained in step S1. Take the lowest ground angle of arrival of the beam in the coverage area of ​​the air platform. ; S6. Taking the ground terminal as the origin, based on the aerial platform height obtained in step S1... and the lowest ground arrival angle of the coverage area beam obtained in step S5 Determine the coverage radius of the main beam. and coverage area S; S7. Based on the main beam coverage radius obtained in step S6 The cumulative distribution of hovering latency of the aerial platform was calculated over the coverage area S. Specifically: S701, Determine the orientation vector of the airborne platform. Calculate the gain of the terminal antenna in that direction at each moment based on the terminal antenna pattern. ; S702. Based on the propagation characteristics of radio signals, calculate the power received from the ground terminal to the air platform at each moment. and signal-to-noise ratio The power received by the ground terminal from the air platform at each moment. and signal-to-noise ratio Specifically: in, For ground terminal transmission power, For free space loss, To monitor the maximum gain of the antenna, Background noise power of the airborne platform receiver system; S703, Traverse the time and record... At that moment, Duration of time If Seconds later and ,but , indicating in Waiting is always necessary It will take several seconds to receive a valid signal from the ground terminal; S704, , For azimuth traversal step, if Repeat steps S701 to S703; otherwise, proceed to the next step. S705, According to the length of stay The cumulative distribution of stay time was obtained through statistical calculation. ; S8, The altitude obtained by the air platform receiver system in step S1 The cumulative distribution of hovering waiting time obtained in hovering step S7 If the signal threshold obtained in step S1 is exceeded, a ground terminal exists within the coverage area.

2. The airborne platform monitoring method for the ground terminal of the NGSO constellation system according to claim 1, characterized in that, In step S1, the airborne platform receiver system parameters include system noise temperature, maximum antenna gain, antenna pattern, and beamwidth, based on the signal-to-noise ratio threshold of the receiving terminal signal. Determine the minimum power that the terminal can receive. as follows: in, This represents the background noise power of the airborne platform receiver.

3. The airborne platform monitoring method for the ground terminal of the NGSO constellation system according to claim 1, characterized in that, In step S2, the NGSO constellation system ground terminal transmit power for: in, For ground terminals in Internal transmission power, For bandwidth.

4. The airborne platform monitoring method for the ground terminal of the NGSO constellation system according to claim 1, characterized in that, In step S3, the orbital parameters of each satellite in the constellation include orbital inclination, right ascension of the ascending node, mean anomaly, argument of perigee, eccentricity, and semi-major axis. This information is used to model the satellite constellation system's orbit and calculate the simulation start time for all satellites within the constellation system. Until the simulation ends Each time point within The position, the time interval is Second.

5. The method for monitoring an airborne platform for a ground terminal of an NGSO constellation system according to claim 1, characterized in that, In step S5, the lowest ground arrival angle of the beam in the coverage area of ​​the airborne platform. for: .

6. The airborne platform monitoring method for the ground terminal of the NGSO constellation system according to claim 1, characterized in that, In step S6, the origin position is taken as the ground terminal. This is the initial azimuth angle from the ground terminal to the air platform. This refers to the azimuth angle of the ground terminal looking at the air platform, where the distance between the ground terminal and the air platform is a fixed value. Determine path loss The airborne platform receiver system remains stationary, traversing the ground terminals along the edge of the coverage area S to obtain the coverage area S of the airborne platform receiver system and the main beam coverage radius. for: in, The elevation angle is the direction of the aerial platform. The altitude of the aerial platform.

7. The airborne platform monitoring method for the ground terminal of the NGSO constellation system according to claim 1, characterized in that, In step S8, if the signal threshold of the receiving system obtained in step S1 is exceeded, and there is a ground terminal in the coverage area, the altitude H is reduced or an air platform antenna with a narrower main lobe width is selected, and steps S6 to S8 are repeated until the ground terminal is found.

8. An aerial platform monitoring system for an NGSO constellation system ground terminal, characterized in that, include: The threshold module establishes an air platform receiver system model based on the air platform receiver system parameters and determines the air platform altitude according to the air platform receiver characteristics. Calculate the signal threshold of the air platform receiver system; The terminal module establishes a ground terminal model based on the ground terminal parameters of the NGSO constellation system. The location module determines the orbital parameters of each satellite in the NGSO constellation system based on the ground terminal communication, establishes the orbital model of the NGSO constellation system, and calculates the simulation start time for all satellites within the NGSO constellation system. Until the simulation ends Each time point within Location data, time interval is Second; The vector module, based on the position data obtained from the position module and combined with the satellite tracking method of the ground terminal, calculates the position of the ground terminal. arrive Every moment within the time period azimuth and pitch angle The data is then used to represent the pointing data at each time step using a unit vector; The angle module uses the ground terminal model obtained from the terminal module and the pitch angle obtained from the vector module. Data determines the minimum elevation angle of the actual communication terminal. The half-power beam ground arrival angle is determined based on the air platform receiver system parameters obtained from the threshold module. Take the lowest ground angle of arrival of the beam in the coverage area of ​​the air platform. ; The area module, with the ground terminal as the origin, uses the aerial platform height obtained from the threshold module. and the lowest ground arrival angle of the coverage area beam obtained by the angle module. Determine the coverage radius of the main beam. and coverage area S; The time module, based on the main beam coverage radius obtained from the region module. The cumulative distribution of hovering latency of the aerial platform was calculated over the coverage area S. Specifically: Determine the orientation vector of the aerial platform Calculate the gain of the terminal antenna in that direction at each moment based on the terminal antenna pattern. ; Based on the propagation characteristics of radio signals, calculate the power received from the ground terminal to the air platform at each moment. and signal-to-noise ratio The power received by the ground terminal from the air platform at each moment. and signal-to-noise ratio Specifically: in, For ground terminal transmission power, For free space loss, To monitor the maximum gain of the antenna, Background noise power of the airborne platform receiver system; Traverse time and record At that moment, Duration of time If Seconds later and ,but , indicating in Waiting is always necessary It will take several seconds to receive a valid signal from the ground terminal; , For azimuth traversal step, if Repeat the steps; otherwise, proceed to the next step. According to the length of stay The cumulative distribution of stay time was obtained through statistical calculation. ; The monitoring module and the aerial platform receiver system obtain the altitude from the threshold module. The cumulative distribution of hovering wait time obtained from the hovering time module If the signal exceeds the threshold obtained by the threshold module, a ground terminal exists within the coverage area.

Images