A space-oriented monte carlo constellation frequency compatibility analysis ground grid segmentation method and system

Abstract

The application provides a space-Monte Carlo constellation frequency compatibility analysis ground grid segmentation method and system, and the method comprises the following steps: establishing a quantitative relationship of simulation resolution, antenna characteristics, satellite parameters and grid interval, taking the constraint that the central angle interval is greater than or equal to the maximum sampling interval, calculating the grid interval according to the latitude and longitude interval calculation formula, and segmenting the ground grid. The application has the advantages that: the simulation result obtained is better than the result of the traditional time-domain extrapolation method, for the interference scene among large-scale constellations, the maximum I / N value obtained has an error of less than 0.1 dB compared with the result of the traditional time-domain extrapolation method; the I / N overrun probability obtained has an error of less than 2% compared with the result of the traditional time-domain extrapolation method.

Description

Technical Field

[0001] This application belongs to the field of constellation compatibility analysis technology, specifically relating to a ground grid segmentation method and system for constellation frequency compatibility analysis oriented towards space Monte Carlo. Background Technology

[0002] With the rapid development and deployment of mega-internet constellations, interference problems between large-scale constellations are becoming increasingly prominent. For compatibility analysis between large-scale constellations, spatial Monte Carlo-based compatibility analysis methods are typically employed to improve simulation efficiency. Existing spatial Monte Carlo analysis methods usually map the grid points obtained after spherical meshing to the satellite positions within the constellation, thereby characterizing the spatial distribution of satellites and achieving compatibility analysis.

[0003] However, existing mesh generation methods result in significant errors between the satellite spatial positions mapped by the mesh and the actual satellite spatial distribution, leading to reduced accuracy in simulation results. Therefore, a reliable mesh generation method is needed to ensure that the satellite spatial positions mapped by the mesh points accurately reflect the actual spatial distribution of satellites in the constellation. Summary of the Invention

[0004] The purpose of this application is to overcome the shortcomings of current ground segmentation methods, which are unable to accurately depict the distribution of satellite sub-satellite points in actual constellations and whose analysis results are difficult to guarantee in terms of accuracy and reliability.

[0005] To achieve the above objectives, this application proposes a ground grid segmentation method for constellation frequency compatibility analysis based on space Monte Carlo, comprising:

[0006] A quantitative relationship between simulation resolution, antenna characteristics, satellite parameters and grid spacing is established. With the geocentric angle spacing being greater than or equal to the maximum sampling interval as a constraint, the grid spacing is calculated according to the latitude and longitude interval calculation formula, and the ground grid is segmented.

[0007] As an improvement to the above method, establishing the quantitative relationship between simulation resolution, antenna characteristics, satellite parameters, and grid spacing includes:

[0008] The quantitative relationship between the geocentric angle of the interfering satellite and the ground station pointed to by the critical value of the antenna half-power main lobe width;

[0009] The relationship between simulation resolution and the off-axis angle of the receiver of the disturbed system;

[0010] The relationship between grid spacing and half beamwidth under the constraint that grid resolution is less than or equal to a set threshold;

[0011] The relationship between the off-axis angle and the geocentric angle of the receiver of the disturbed system;

[0012] The relationship between the change in off-axis angle and the change in geocentric angle.

[0013] As an improvement to the above method, the quantitative relationship between the geocentric angle of the interfering satellite and the ground station pointed to by the critical value of the antenna half-power main lobe width is expressed as follows:

[0014] ;

[0015] in, The geocentric angle between the interfering NGSO satellite and the ground station, indicated by the critical value of the antenna's half-power main lobe width. Represents the Earth's radius; in the uplink scenario This represents the half-power bandwidth of the earth station antenna at the transmitting end of the jamming system in the downlink scenario. This indicates the half-power bandwidth of the earth station antenna at the receiving end of the disturbed system; h To interfere with satellite altitude.

[0016] As an improvement to the above method, the correlation between the simulation resolution and the off-axis angle of the receiver of the disturbed system is expressed as follows:

[0017] ;

[0018] in, This represents the difference in interference noise ratio when the nadir points of adjacent reference satellites are located in two grids. Indicates the offset angle of the antenna beam; This indicates the change in the off-axis angle of the receiver of the disturbed system.

[0019] As an improvement to the above method, under the constraint that the grid resolution is less than or equal to a set threshold, the relationship between the grid spacing and the half-beamwidth is expressed as follows:

[0020] ;

[0021] in, Set a threshold for the resolution of the simulation results.

[0022] As an improvement to the above method, the relationship between the off-axis angle and the geocentric angle of the receiving end of the disturbed system is expressed as follows:

[0023]

[0024] in, The ground point of the interfering satellite is located in the grid. a The geocentric angle between the interfering satellite and the disturbed ground station; The ground point of the interfering satellite is located in the grid. a The off-axis angle of the receiver of the disturbed system.

[0025] As an improvement to the above method, the correlation between the change in off-axis angle and the change in geocentric angle is expressed as follows:

[0026]

[0027] in, The change in geocentric angle caused by the change in the spatial position of the interference satellite.

[0028] As an improvement to the above method, the formula for calculating the latitude and longitude interval is expressed as follows:

[0029] The latitude and longitude intervals of the grid division satisfy the following formula:

[0030]

[0031] in, This indicates the interval between two adjacent grids.

[0032] This application also provides a ground grid segmentation system for constellation frequency compatibility analysis based on space Monte Carlo, implemented using the above method. The system includes:

[0033] The module for acquiring basic network spacing data is used to establish a quantitative relationship between simulation resolution, antenna characteristics, satellite parameters, and grid spacing.

[0034] The grid interval acquisition module is used to calculate the grid interval based on the latitude and longitude interval calculation formula, with the geocentric angle interval being greater than or equal to the maximum sampling interval as a constraint.

[0035] Compared with existing technologies, the advantages of this application are:

[0036] 1. The simulation results obtained by the method provided in this application are better than those obtained by the traditional time-domain extrapolation method. For large-scale inter-constellation interference scenarios, the error between the obtained maximum I / N value and the result obtained by the traditional time-domain extrapolation method is less than 0.1dB; the error between the obtained I / N over-limit probability and the result obtained by the traditional time-domain extrapolation method is less than 2%.

[0037] 2. The method provided in this application reveals the mapping mechanism between constellation interference configuration and lumped interference probability distribution, and obtains the optimal segmentation model of NGSO constellation grid point distribution, thereby improving the accuracy of simulation results. Attached Figure Description

[0038] Figure 1 The diagram shows the ground grid segmentation method for constellation frequency compatibility analysis oriented towards space Monte Carlo.

[0039] Figure 2 The figure shows the cumulative probability distribution curves of I / N for different grid partitioning methods under a jamming system with a scale of 1000 satellites;

[0040] Figure 3 The figure shows the cumulative probability distribution curves of I / N for different grid division methods under a jamming system with a scale of 3000 satellites;

[0041] Figure 4 The figure shows the cumulative probability distribution curves of I / N for different grid partitioning methods under a jamming system with 6000 satellites.

[0042] Figure 5 The figure shows the cumulative probability distribution curves of I / N for different grid partitioning methods under a scale of 10,000 interference systems. Detailed Implementation

[0043] The technical solution of this application will be described in detail below with reference to the accompanying drawings.

[0044] This application proposes a ground grid segmentation method and system for constellation frequency compatibility analysis based on space Monte Carlo, reveals the mapping mechanism between constellation interference configuration and lumped interference probability distribution, constructs a grid partitioning objective function based on antenna beam characteristics, and obtains an optimal segmentation model for the grid point distribution of non-geosynchronous orbit satellite constellations.

[0045] Example 1

[0046] like Figure 1 As shown, this application provides a ground grid segmentation method for constellation frequency compatibility analysis based on space Monte Carlo simulation. The method includes: establishing a quantitative relationship between simulation resolution, antenna characteristics, satellite parameters, and grid spacing; using a geocentric angle interval greater than or equal to the maximum sampling interval as a constraint; calculating the grid spacing according to the latitude and longitude interval calculation formula; and segmenting the ground grid. The specific process is as follows:

[0047] The probability distribution function of the reference satellite's projection on the ground is continuous, and a point on the function corresponds to a point on the ground. Since these points are continuous and cannot be enumerated, it is necessary to discretize and sample these continuous points to facilitate spatial enumeration.

[0048] Therefore, we divide the ground into grids to facilitate the calculation of the probability of a reference satellite being near a certain location. During the simulation, it is challenging to implement the lumped interference of a single grid using algorithms. With a reasonable grid division, the lumped interference of the entire grid can be represented by the lumped interference experienced at the grid's center point.

[0049] For the worst-case interference scenario, namely the co-location scenario of the interfered and the interfering earth station, the off-axis angle of the interfering system transmitter is... When the value is 0, the single-input interference experienced by the disturbed ground station is shown in the following formula. We only need to pay attention to the change in the off-axis angle of the receiver.

[0050]

[0051] in, Indicates interference power; Indicates noise power; This indicates the transmission power that interferes with the NGSO satellite; Indicates the interference with the NGSO satellite antenna gain. Indicates the antenna gain of the disturbed earth station, angle Indicates the off-axis angle of the received signal from the disturbed earth station. This indicates link loss.

[0052] The connection between the disrupted satellite and the disrupted ground station and the first The angle between the line connecting the interfering reference satellite and the disturbed ground station at each location. As shown in the following formula.

[0053]

[0054] in, The Earth-fixed coordinates of the disturbed satellite. For the first p Earth-fixed coordinates of interfering NGSO satellites at various locations The coordinates of the disturbed ground station are in the Earth-fixed system. For dot product, This indicates scalar multiplication.

[0055] In the Interference caused by the jamming system to the affected ground station when there is a jamming reference satellite at a certain location. It can be represented as

[0056]

[0057] in, To interfere with the peak gain of satellite launches.

[0058] The reference satellite nadir point is located in the adjacent grid. a , b The interference noise ratios generated at that time were respectively and .

[0059]

[0060] in, This is the difference in interference noise ratio when the base point of the reference satellite is located in two adjacent grids.

[0061] Adjacent grids The interval between them is As shown in the following formula.

[0062]

[0063] in, For the first a Earth-fixed coordinates of the interfering NGSO satellite at each location.

[0064] According to the ITU-RS series of recommendations, the gain curve of a ground station antenna within half-power bandwidth is considered to satisfy a parabolic form. Therefore, the curve of the decrease in antenna gain is as follows.

[0065]

[0066] in, It is the offset angle of the antenna beam. It is a constant coefficient. The relationship between the beamwidth and the half-beamwidth is shown in the following formula.

[0067]

[0068] In the uplink scenario This represents the half-power bandwidth of the earth station antenna at the transmitting end of the jamming system in the downlink scenario. This indicates the half-power bandwidth of the earth station antenna at the receiving end of the disturbed system.

[0069] We can obtain:

[0070]

[0071] The difference in interference-to-noise ratio when the nadir points of adjacent reference satellites are located in two grids satisfies the following conditions with respect to the adjacent grid spacing:

[0072]

[0073] If grid spacing Too small a mesh size will lead to an increase in the computational load of the simulation and the mesh spacing. If the value is too large, the simulation results will have an excessively high resolution, resulting in significant differences in the interference values ​​at different points and reducing the accuracy of the simulation results.

[0074] Therefore, the objective of this application is to maximize the spacing between adjacent grids while ensuring simulation accuracy. In other words, there exists a resolution threshold for the simulation results, and the goal is to find the maximum grid spacing while ensuring that the simulation result resolution does not exceed this threshold. This problem can be expressed as:

[0075]

[0076] in, This is the threshold for the resolution of the simulation results.

[0077] The geocentric angle between the interfering NGSO satellite and the ground station, as indicated by the critical value of the antenna's half-power main lobe width. As shown below.

[0078]

[0079] in, This represents the Earth's radius.

[0080] The relationship between resolution and the off-axis angle of the receiver in the disturbed system satisfies:

[0081]

[0082] Under the condition that the result resolution is no greater than the threshold, the change in off-axis angle at the receiver of the disturbed system. The relationship between the sampling interval and the half-beamwidth is shown in the following formula.

[0083]

[0084] When the reference satellite nadir point of the interference system is located in the grid a The relationship between the off-axis angle of the receiving end of the disturbed system and the geocentric angle between the interfering satellite and the disturbed ground station is shown in the following formula.

[0085]

[0086] in, The ground point of the interfering satellite is located in the grid. a The off-axis angle of the receiver of the disturbed system. The ground point of the interfering satellite is located in the grid. a The geocentric angle between the interfering satellite and the disturbed ground station. h To interfere with satellite altitude.

[0087] We can obtain:

[0088]

[0089] in, The change in off-axis angle at the receiver of the disturbed system. The change in geocentric angle caused by the change in the spatial position of the interference satellite.

[0090] Since the geocentric angle interval is greater than or equal to the maximum sampling interval, the latitude and longitude interval (maximum sampling interval) of the grid division should satisfy the following condition.

[0091]

[0092] in, This represents the geocentric angle between the interfering NGSO satellite and the ground station, as indicated by the critical value of the antenna's half-power main lobe width.

[0093] The method provided in this application was used for testing. The interfering NGSO satellite system referenced the orbital configuration of the Starlink constellation, i.e., satellites with an orbital altitude of 630 km. The interfered NGSO satellite system adopted a sun-synchronous orbit with an orbital altitude of 1200 km. All satellite antennas used the ITU-R S.1528 antenna model. The ground station antenna model used the ITU-R S.580-6 antenna model. The visibility elevation angle threshold between the NGSO satellites and the ground station was set to 20°. Table 1 shows the downlink simulation parameters of the interfered constellation system, and Table 2 shows the downlink simulation parameters of the interfering constellation system.

[0094] Table 1 Downlink Simulation Parameters of the Disturbed System

[0095]

[0096] Table 2 Downlink Simulation Parameters of the Interference System

[0097]

[0098] The simulation parameters of the time-domain extrapolation method are shown in Table 3.

[0099] Table 3 Compatibility simulation parameters based on time-domain extrapolation

[0100]

[0101] The cumulative I / N distribution curves obtained using the mesh generation method proposed in this application for interference scenarios of different scales are shown below. Figures 2-5 As shown in the figure, the Antenna Characteristics-Driven Adaptive Segmentation Method (ACDAS) is an adaptive segmentation method driven by antenna characteristics; the Spherical Uniform Triangular Segmentation Method (SUTS) is a spherical uniform triangular segmentation method; the Equal Latitude-Longitude Spherical Segmentation Method (ELLSS) is a uniform latitude and longitude tennis surface segmentation method; and the time-extrapolated analysis method (10s) represents an analysis method based on time extrapolation (with a step size of 10s).

[0102] When using equidistant uniform distribution or equal latitude and longitude interval methods for simulation analysis, compared with traditional time-domain extrapolation methods, they cannot fully analyze all possible interference scenarios and are difficult to accurately reflect the worst interference situation. However, the maximum I / N value obtained by the method proposed in this application is better than that of traditional time-domain extrapolation methods, accurately characterizing the interference situation and reflecting the worst interference. Compared with the method of this application, the simulation accuracy of equidistant uniform distribution or equal latitude and longitude interval methods will be significantly reduced in areas where the interference value changes drastically. However, as the constellation size in the simulation scenario increases, the error between the maximum I / N value obtained by the equidistant uniform segmentation method and the adaptive interval segmentation method gradually decreases, and the simulation reliability is improved to a certain extent. However, the error between the maximum I / N value obtained by the equal latitude and longitude interval segmentation method and the method of this application gradually increases with the increase of constellation size, and the simulation reliability decreases significantly. Therefore, for interference analysis between large-scale constellations, the method provided in this application can ensure the accuracy of the analysis results.

[0103] The method proposed in this application outperforms simulation results from time-domain analysis methods with smaller simulation step sizes, exhibiting higher reliability in interference analysis and accurately characterizing the most severe interference. This application provides an effective modeling method for improving the accuracy of spatial Monte Carlo-based spectrum simulation analysis, and has certain practical engineering value.

[0104] Example 2

[0105] This application also provides a ground grid segmentation system for constellation frequency compatibility analysis based on space Monte Carlo, implemented using the above method. The system includes:

[0106] The module for acquiring basic network spacing data is used to establish a quantitative relationship between simulation resolution, antenna characteristics, satellite parameters, and grid spacing.

[0107] The grid interval acquisition module is used to calculate the grid interval based on the latitude and longitude interval calculation formula, with the geocentric angle interval being greater than or equal to the maximum sampling interval as a constraint.

[0108] This application may also provide a computer device, including: at least one processor, memory, at least one network interface, and a user interface. The various components in this device are coupled together via a bus system. It is understood that the bus system is used to implement communication between these components. In addition to a data bus, the bus system also includes a power bus, a control bus, and a status signal bus.

[0109] The user interface can include a display, keyboard, or clicking device. Examples include a mouse, trackball, touchpad, or touchscreen.

[0110] It is understood that the memory in the embodiments disclosed in this application may be volatile memory or non-volatile memory, or may include both volatile and non-volatile memory. The non-volatile memory may be read-only memory (ROM), programmable read-only memory (PROM), erasable programmable read-only memory (EPROM), electrically erasable programmable read-only memory (EEPROM), or flash memory. The volatile memory may be random access memory (RAM), which is used as an external cache. By way of example, but not limitation, many forms of RAM are available, such as Static Random Access Memory (SRAM), Dynamic Random Access Memory (DRAM), Synchronous DRAM (SDRAM), Double Data Rate SDRAM (DDRSDRAM), Enhanced Synchronous DRAM (ESDRAM), Synchlink DRAM (SLDRAM), and Direct Rambus RAM (DRRAM). The memories described herein are intended to include, but are not limited to, these and any other suitable types of memory.

[0111] In some implementations, the memory stores elements such as executable modules or data structures, or subsets thereof, or extended sets thereof: operating systems and applications.

[0112] The operating system includes various system programs, such as the framework layer, core library layer, and driver layer, used to implement various basic business functions and handle hardware-based tasks. The application programs include various applications, such as media players and browsers, used to implement various application functions. Programs implementing the methods of the embodiments of this disclosure can be included in the application programs.

[0113] In the above embodiments, the processor can also invoke programs or instructions stored in memory, specifically programs or instructions stored in an application program, for the following purposes:

[0114] Follow the steps described above.

[0115] The above methods can be applied to or implemented by a processor. The processor may be an integrated circuit chip with signal processing capabilities. During implementation, each step of the above methods can be completed by integrated logic circuits in the processor's hardware or by software instructions. The processor can be a general-purpose processor, a digital signal processor (DSP), an application-specific integrated circuit (ASIC), a field-programmable gate array (FPGA), or other programmable logic devices, discrete gate or transistor logic devices, or discrete hardware components. It can implement or execute the methods, steps, and logic diagrams disclosed above. The general-purpose processor can be a microprocessor or any conventional processor. The steps of the disclosed methods can be directly implemented by a hardware decoding processor, or by a combination of hardware and software modules in the decoding processor. The software modules can reside in random access memory, flash memory, read-only memory, programmable read-only memory, electrically erasable programmable memory, registers, or other mature storage media in the art. This storage medium is located in memory; the processor reads information from the memory and, in conjunction with its hardware, completes the steps of the above methods.

[0116] It is understood that the embodiments described in this application can be implemented using hardware, software, firmware, middleware, microcode, or a combination thereof. For hardware implementation, the processing unit can be implemented in one or more application-specific integrated circuits (ASICs), digital signal processors (DSPs), digital signal processing devices (DSPDs), programmable logic devices (PLDs), field-programmable gate arrays (FPGAs), general-purpose processors, controllers, microcontrollers, microprocessors, other electronic units for performing the functions described in this application, or combinations thereof.

[0117] For software implementation, the technology of this application can be implemented by executing the functional modules (e.g., procedures, functions, etc.) of this application. The software code can be stored in memory and executed by a processor. The memory can be implemented in the processor or outside the processor.

[0118] This application may also provide a non-volatile storage medium for storing a computer program. When the computer program is executed by a processor, it can implement the steps in the above method embodiments.

[0119] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application and are not intended to limit it. Although this application has been described in detail with reference to the embodiments, those skilled in the art should understand that modifications or equivalent substitutions to the technical solutions of this application do not depart from the spirit and scope of the technical solutions of this application, and should all be covered within the scope of the claims of this application.

Claims

1. A ground grid segmentation method for constellation frequency compatibility analysis oriented towards space Monte Carlo, comprising: Establish a quantitative relationship between simulation resolution, antenna characteristics, satellite parameters and grid spacing. With the geocentric angle spacing being greater than or equal to the maximum sampling interval as a constraint, calculate the grid spacing according to the latitude and longitude interval calculation formula, and divide the ground grid. The establishment of a quantitative relationship between simulation resolution, antenna characteristics, satellite parameters, and grid spacing includes: The quantitative relationship between the geocentric angle of the interfering satellite and the ground station pointed to by the critical value of the antenna half-power main lobe width; The relationship between simulation resolution and the off-axis angle of the receiver of the disturbed system; The relationship between grid spacing and half beamwidth under the constraint that grid resolution is less than or equal to a set threshold; The relationship between the off-axis angle and the geocentric angle of the receiver of the disturbed system; The relationship between the change in off-axis angle and the change in geocentric angle; The quantitative relationship between the geocentric angle between the interfering satellite and the ground station pointed to by the critical value of the antenna's half-power main lobe width is expressed as: ； in, The geocentric angle between the interfering NGSO satellite and the ground station, indicated by the critical value of the antenna's half-power main lobe width. Represents the Earth's radius; in the uplink scenario This represents the half-power bandwidth of the earth station antenna at the transmitting end of the jamming system in the downlink scenario. This indicates the half-power bandwidth of the earth station antenna at the receiving end of the disturbed system; h To interfere with satellite altitude; The relationship between the simulation resolution and the off-axis angle of the receiver of the disturbed system is expressed as follows: ； in, This represents the difference in interference noise ratio when the nadir points of adjacent reference satellites are located in two grids. Indicates the offset angle of the antenna beam; This indicates the change in the off-axis angle of the receiver in the disturbed system; Under the constraint that the grid resolution is less than or equal to a set threshold, the relationship between the grid spacing and the half-beamwidth is expressed as follows: ； in, Set a threshold for the resolution of the simulation results; The relationship between the off-axis angle and the geocentric angle of the receiver of the disturbed system is expressed as follows: ； in, The ground point of the interfering satellite is located in the grid. a The geocentric angle between the interfering satellite and the disturbed ground station; The ground point of the interfering satellite is located in the grid. a The off-axis angle of the receiver of the disturbed system; The relationship between the change in off-axis angle and the change in geocentric angle is expressed as follows: ； in, The change in geocentric angle caused by the change in the spatial position of the interference satellite.

2. The ground grid segmentation method for constellation frequency compatibility analysis based on space Monte Carlo as described in claim 1, characterized in that, The formula for calculating the latitude and longitude interval is expressed as follows: The latitude and longitude intervals of the grid division satisfy the following formula: ； in, This indicates the interval between two adjacent grids.

3. A ground grid segmentation system for constellation frequency compatibility analysis oriented towards space Monte Carlo, implemented based on the method described in any one of claims 1-2, characterized in that, The system includes: The module for acquiring basic network spacing data is used to establish a quantitative relationship between simulation resolution, antenna characteristics, satellite parameters, and grid spacing; and The grid interval acquisition module is used to calculate the grid interval based on the latitude and longitude interval calculation formula, with the geocentric angle interval being greater than or equal to the maximum sampling interval as a constraint.

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