Method for Defining the Protection Area Scope of a GEO Earth Station to Avoid Interference from Large-Scale LEO Constellations

Abstract

The present invention relates to the field of satellite communication technologies, and specifically discloses a method for defining the protection area range of a GEO earth station to avoid interference from a large-scale LEO constellation, including the following steps: S01: Calculate the threshold of the interference expected value according to the outage probability of the GEO communication system; S02: Establish a protection area model and set a protection radius, construct an interference scenario model according to the protection radius, and determine the calculation formula for the interference of the LEO satellite on the GEO earth station; S03: Use the Fibonacci grid method to obtain the satellite spatial position coordinates in the interference scenario model; S04: Based on the calculation formula for the interference of the LEO satellite on the GEO earth station and the satellite spatial position coordinates, determine the calculation formula for the interference expected value; S05: According to the threshold of the interference expected value and the calculation formula for the interference expected value, determine the value of the protection boundary radius of the protection area, and further determine the protection area range.

Description

Technical Field

[0001] The present invention relates to the field of satellite communication technology, and specifically relates to a method for defining the protection area range of a GEO earth station to avoid interference from a large-scale LEO constellation. Background Art

[0002] With the continuous development of low-earth orbit (LEO) satellite communication systems, the number of LEO satellites is increasing. According to the static spectrum allocation principle in the Radio Regulations (RR), the geostationary orbit (GEO) satellite communication system and the LEO satellite communication system share frequencies. Therefore, interference from the LEO satellite communication system to the GEO satellite communication system is inevitable in some frequency bands. Also, since the GEO satellite system has priority, the LEO satellite communication system must not cause harmful interference to the GEO satellite communication system and cannot seek interference protection from the GEO satellite system. Therefore, it is crucial to determine the protection area of the GEO satellite communication system.

[0003] The solutions in the prior art include calculating the interference expected value using the method of double integral. The calculation expression of this method is complex and not easy to analyze, and its model is based on a two-dimensional plane, while the spectrum coexistence scenario between the LEO satellite communication system and the GEO satellite communication system is mostly based on a three-dimensional space. Moreover, in the scenario of a randomly and uniformly distributed giant constellation, the number of satellites is huge, and it is difficult to obtain the specific positions of each satellite, resulting in a high complexity in calculating the interference expected value. Summary of the Invention

[0004] Aiming at the above problems, the purpose of the present invention is to provide a method for defining the protection area range of a GEO earth station to avoid interference from a large-scale LEO constellation. Based on a three-dimensional space model, the Fibonacci grid method can be used to quickly and approximately represent the coordinates of satellites, further obtain the cumulative interference power of the GEO system, and obtain the interference expected value. And according to the interference threshold, the protection radius is determined, and then the interference protection area is determined. The calculation expression is simple and easy to analyze, greatly reducing the complexity.

[0005] The technical solution adopted by the present invention is: a method for defining the protection area range of a GEO earth station to avoid interference from a large-scale LEO constellation, including the following steps:

[0006] S01: Calculate the threshold of the interference expected value according to the outage probability of the GEO communication system;

[0007] S02: Establish a protection area model and set a protection radius, construct an interference scenario model according to the protection radius, and determine the calculation formula for the interference of LEO satellites on the GEO earth station;

[0008] S03: Use the Fibonacci grid method to obtain the satellite spatial position coordinates in the interference scenario model;

[0009] S04: Determine the calculation formula for the interference expectation value based on the calculation formula for the interference of the LEO satellite on the GEO earth station and the satellite spatial position coordinates.

[0010] S05: Determine the protection boundary radius value of the protection area according to the threshold value of the interference expectation value and the calculation formula for the interference expectation value, and then determine the scope of the protection area.

[0011] Preferably, in step S01, the threshold value of the interference expectation value is calculated based on the following formula:

[0012]

[0013] N GEO = KTW;

[0014] Where E(I) is the interference expectation value, ε is the outage probability, 0 ≤ ε ≤ 1, P GEO is the received power of the GEO system, C 0 is the minimum transmission rate required to ensure normal communication of the GEO communication system, N GEO is the GEO system noise, K is the Boltzmann constant, T is the GEO system noise temperature, and W is the bandwidth.

[0015] Preferably, in step S02, the calculation formula for the interference I of the LEO satellite on the GEO earth station is determined as:

[0016]

[0017] Where I is the interference of the LEO satellite on the GEO earth station, P ns is the transmit power of the LEO satellite, G ns (θ 2 ) is the antenna gain of the LEO satellite in the θ 2 direction, G es (θ 1 ) is the antenna gain of the GEO earth station in the θ 1 direction, c is the speed of light, f is the center frequency of the spectrum, d is the distance between the LEO satellite and the GEO earth station, φ k is the Rice parameter.

[0018] Preferably, in step S03, the satellite spatial position coordinates are:

[0019]

[0020] Where R e is the radius of the earth, H leo is the height of the LEO satellite, n is the serial number, m is the serial number when the GEO earth station and the LEO satellite are just visible, N is the total number of LEO satellites, and φ is the golden ratio.

[0021] Preferably, in step S04, the interference expected value calculation formula is determined as;

[0022]

[0023]

[0024]

[0025]

[0026]

[0027]

[0028]

[0029] Among them, E(I) is the interference expected value, P ns is the transmission power of the LEO satellite, G ns (θ 2n ) is the antenna gain of the LEO satellite in the θ 2n direction, G es (θ 1n ) is the antenna gain of the GEO earth station in the θ 1n direction, c is the speed of light, f is the center frequency of the spectrum, d n is the distance between the GEO earth station and the nth LEO satellite, φ k is the Rice parameter, m is the serial number when the GEO earth station and the LEO satellite are just visible, N is the total number of LEO satellites, H geo is the height of the GEO satellite, θ 1n is the off-axis angle of the GEO earth station in the direction of the nth LEO satellite, θ 2n is the off-axis angle of the nth LEO satellite in the direction of the GEO earth station.

[0030] Preferably, in step S05, the protection boundary radius value R 0 of the protection area is:

[0031]

[0032]

[0033] Among them, R e is the radius of the earth, ν n represents the central angle between the GEO earth station and the nth LEO earth station.

[0034] Preferably, when the distance between the LEO earth station and the GEO earth station is greater than the protection boundary radius value, the LEO satellite will not interfere with the GEO satellite system.

[0035] Preferably, the interference scenario model is established based on the satellite downlink.

[0036] Preferably, the interference scenario model is established based on the satellite uplink.

[0037] Advantages of the above technical solutions:

[0038] (1) By representing the coordinates of the interfering satellite with the Fibonacci grid method, the interference expression of the interfering satellite on the earth station is derived. Then, the interference power values are accumulated and divided by the total number of satellites participating in the interference to obtain the interference expectation value. Further, the variation relationship between the interference expectation and the protection radius is obtained. Finally, the value of the interference protection radius is obtained by comparing with the interference threshold. At the same time, the relationship between the height of the interfering satellite and the interference expectation value is also analyzed, providing a certain reference for the layout of the earth station.

[0039] (2) For a uniformly distributed giant constellation, based on a three-dimensional space model, this method innovatively uses the Fibonacci grid method to represent satellite coordinates, which is of great significance in quickly determining the interference protection area.

[0040] (3) The method proposed in the present invention has a simple expression, is easy to analyze, has a low complexity, and a high calculation efficiency. It can quickly calculate the interference expectation value and can analyze a single link, with higher efficiency. Description of the Drawings

[0041] Figure 1 It is a flowchart of the method for defining the protection area of the GEO earth station to avoid interference from a large-scale LEO constellation provided by the present invention;

[0042] Figure 2 It is a schematic diagram of the frequency coexistence scenario of a GEO satellite and multiple LEO earth stations provided by an embodiment of the present invention;

[0043] Figure 3 It is a schematic diagram of the frequency coexistence scenario of the GEO and LEO systems in the downlink provided by an embodiment of the present invention;

[0044] Figure 4 It is a schematic diagram of the Fibonacci grid points on the unit sphere provided by an embodiment of the present invention;

[0045] Figure 5 It is a schematic diagram of the frequency coexistence scenario of the GEO system and multiple LEO systems in the downlink provided by an embodiment of the present invention;

[0046] Figure 6The curve graph of the change in the expected interference value and the protection radius in the downlink provided by an embodiment of the present invention;

[0047] Figure 7 The curve graph of the change in the expected interference value and the protection radius in the uplink provided by an embodiment of the present invention. Specific implementation manners

[0048] The following further describes in detail the implementation manners of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than an exhaustive list of all embodiments. It should be noted that, without conflict, the embodiments in the present application and the features in the embodiments can be combined with each other.

[0049] Terms such as "first" and "second" in the specification and claims (if any) are used to distinguish similar objects, and do not necessarily describe a specific order or sequence. It should be understood that such data can be interchanged under appropriate circumstances, so that the embodiments described herein can be implemented in an order other than that illustrated or described herein. In addition, the terms "include" and "have" and any variations thereof are intended to cover non-exclusive inclusion. For example, a process, method, system, product or device that includes a series of steps or units does not necessarily limit to those clearly listed steps or units, but may include other steps or units not clearly listed or inherent to these processes, methods, products or devices.

[0050] It should be understood that the term " / and" used herein is only a relationship describing associated objects, indicating that three relationships may exist. For example, A / and B may represent: A exists alone, A and B exist simultaneously, and B exists alone. In addition, the character " / " herein generally represents an "or" relationship between the associated objects before and after.

[0051] The present invention provides a method for calculating the protection area radius of a GEO earth station to avoid interference from a large-scale LEO constellation, so as to alleviate the problems of complex analytical formulas and complex calculation processes in the prior art, and gives the value of the interference protection radius, providing a reference for the layout of LEO earth stations, and at the same time analyzing the influence of different satellite heights on the expected interference value.

[0052] Such as Figure 1 The flowchart of the method for defining the protection area range of a GEO earth station to avoid interference from a large-scale LEO constellation provided by the present invention includes the following steps:

[0053] S01: Calculate the threshold value of the expected interference value according to the outage probability of the GEO communication system;

[0054] S02: Establish a protection area model and set a protection radius, construct an interference scenario model according to the protection radius, and determine the calculation formula for the interference of LEO satellites on GEO earth stations;

[0055] S03: Use the Fibonacci grid method to obtain the satellite spatial position coordinates in the interference scenario model;

[0056] S04: Based on the calculation formula for the interference of LEO satellites on GEO earth stations and the satellite spatial position coordinates, determine the calculation formula for the interference expected value;

[0057] S05: According to the threshold of the interference expected value and the calculation formula for the interference expected value, determine the protection boundary radius value of the protection area, and further determine the protection area range.

[0058] Embodiment 1

[0059] In this embodiment, taking the downlink as an example, by establishing an interference scenario and an interference satellite spatial position model for the downlink, the interference expression for the satellite downlink is derived. The interference expected value is calculated by adding up the interference values of each link and dividing by the total number of interfering satellites. The protection radius is determined according to the interference threshold, and the interference protection area is further determined.

[0060] Preferably, this embodiment specifically includes the following steps:

[0061] Obtain the threshold of the interference expected value

[0062] According to Shannon's theorem, the transmission rate of the GEO system can be expressed as:

[0063]

[0064] N GEO = KTW(2)

[0065] where T 0 is the transmission rate of the GEO system, P GEO is the received power of the GEO system, I is the total interference suffered by the GEO system, N GEO is the GEO system noise, K is the Boltzmann constant, T is the GEO system noise temperature, and W is the bandwidth.

[0066] The outage probability threshold of the GEO communication system is expressed as:

[0067] P(T 0 ≤ C 0 ) ≤ ε(3)

[0068] where C 0 is the minimum transmission rate required to ensure normal communication of the GEO communication system, ε is the outage probability, and 0 ≤ ε ≤ 1.

[0069] Substituting equations (1) and (2) into equation (3) gives:

[0070]

[0071] According to the Markov inequality, equation (4) can be expressed as:

[0072]

[0073] Therefore, the threshold of the expected interference value can be expressed as:

[0074]

[0075] E(I) is the expected interference value, ε is the outage probability, P GEO is the received power of the GEO system, C 0 is the minimum transmission rate required to ensure normal communication of the GEO communication system, N GEO is the noise of the GEO system.

[0076] Establish a protection area model

[0077] Figure 2 is a schematic diagram of the frequency coexistence scenario between a GEO satellite and multiple LEO earth stations, including one GEO satellite and a certain number of LEO earth stations. The LEO earth stations are randomly and uniformly distributed. To ensure that the quality of the GEO communication system is not affected, a protection range is set with the GEO earth station as the center. The LEO earth stations are randomly and uniformly distributed within the circular ring with a radius from R 0 to R, and R 0 is the protection radius. Outside the protection range, that is, within the circular ring, no matter where the LEO satellite moves, it will not interfere with the GEO satellite system, ensuring the communication ability of the GEO system.

[0078] Establish an interference scenario model

[0079] Figure 3 is a schematic diagram of the frequency coexistence scenario between the GEO and LEO systems in the provided downlink. It is assumed that the GEO earth station is located at the sub-satellite point of the GEO satellite, and the LEO earth station is located at the sub-satellite point of the LEO satellite. The GEO earth station is interfered by the LEO satellite in the downlink. When the LEO satellite approaches or passes through the line connecting the GEO satellite and its earth station, the interference is particularly severe.

[0080] Figure 3 In, O is the center of the earth, and a space rectangular coordinate system is established with the center of the earth as the origin. θ 1 is the off-axis angle of the GEO earth station in the direction of the LEO satellite, θ 2Let \(\theta\) be the off-axis angle of the LEO satellite in the direction of the GEO earth station, \(d\) be the distance between the LEO satellite and the GEO earth station, \(r\) be the distance between the GEO earth station and the LEO earth station, and \(\nu\) be the geocentric angle between the GEO earth station and the LEO earth station.

[0081] Establish the interference calculation formula of the LEO satellite to the GEO earth station

[0082] The interference calculation formula of the LEO satellite to the GEO earth station is:

[0083]

[0084] Among them, \(P\) ns is the transmission power of the LEO satellite, \(G\) ns (\(\theta\) 2 ) is the antenna gain of the LEO satellite in the \(\theta\) 2 direction, \(G\) es (\(\theta\) 1 ) is the antenna gain of the GEO earth station in the \(\theta\) 1 direction, \(c\) is the speed of light (\(c = 3\times10\) 8 m / s), \(f\) is the center frequency of the spectrum, \(d\) is the distance between the LEO satellite and the GEO earth station, and \(\varphi\) k is the Rice parameter.

[0085] The antenna pattern of the LEO satellite refers to ITU-R S.1528, and the expression is as follows:

[0086]

[0087] Among them, \(G\) max is the maximum gain of the satellite antenna, \(\theta\) b is the half-power beam width of the antenna, \(L\) S = -6.75 dBi, \(L\) F = 5 dBi, and other variables are described as follows:

[0088]

[0089] The antenna pattern of the GEO earth station refers to ITU-R S.456, and the expression is as follows:

[0090]

[0091] Among them, the ratio of the antenna radius to the wavelength \(D / \lambda\leq50\), and \(\theta\) m = max(2, 114(D / \lambda) -1.09 ) degrees.

[0092] Establish the spatial position model of the LEO satellite

[0093] Using the Fibonacci grid method, as Figure 4 is a schematic diagram of Fibonacci grid points on the unit sphere. A spatial rectangular coordinate system is established with the center of the sphere as the origin. On the unit sphere, the coordinates of N uniformly distributed points are as follows: The coordinates of each point are uniquely determined by the serial number n,

[0094]

[0095] where the constant φ is the golden ratio, with a value of 0.618.

[0096] Solving for the spatial position coordinates of the satellite, as Figure 5 shown in the schematic diagram of the frequency coexistence scenario of the GEO system and multiple LEO systems in the downlink. A spatial rectangular coordinate system is established with the center of the earth as the origin and the line connecting the center of the earth and the GEO earth station as the Z-axis. It is easy to know that the coordinates of the GEO earth station are A(0, 0, R e ), and the coordinates of the GEO satellite are C(0, 0, R e + H geo ). When the LEO earth station is deployed within the gray area, no matter where the LEO satellite moves, it will not interfere with the GEO system. Therefore, it is necessary to determine the boundary value of the interference protection radius R 0 . Since all LEO earth stations are randomly and uniformly distributed, the corresponding LEO satellites are also randomly and uniformly distributed. Therefore, we use the Fibonacci grid method to quickly give the coordinates of the LEO satellites. However, interference is only possible when the GEO earth station and the LEO satellite are visible. Assuming that N is set to 10000 and the starting serial number m of the satellite coordinates is set to 9000, the coordinates D n (x n , y n , z n ) of the LEO satellites are as follows:

[0097]

[0098] where R e is the radius of the earth, H leo is the height of the LEO satellite, n is the serial number, m is the serial number when the GEO earth station and the LEO satellite are just visible, N is the total number of LEO satellites, and φ is the golden ratio.

[0099] Calculating the expected value of interference

[0100] After giving the coordinates of each point, the vector is expressed as:

[0101]

[0102]

[0103]

[0104]

[0105] Furthermore, θ 1n and θ 2n and d n are expressed as:

[0106]

[0107]

[0108]

[0109] Based on the previous analysis, since all LEO earth stations are randomly and uniformly distributed within the circular ring with a radius from R 0 to R, the interference received by the GEO earth station comes from the LEO satellite transmitting end. The calculation formula for the expected value of interference in Equation (7) is:

[0110]

[0111] Substitute Equation (17), Equation (18), and Equation (19) into Equation (20), and the calculation formula for the expected value of interference from multiple LEO satellites to the GEO earth station can be obtained.

[0112] According to the above mathematical expression for the expected value of interference from multiple LEO satellites to the GEO earth station and the threshold formula (6) of the expected value of interference, the value of n is determined.

[0113] Then, according to ν = r / R e , substitute the value of n to obtain the boundary value of the protection radius R 0 :

[0114]

[0115] where R e is the radius of the earth, and ν n represents the central angle between the GEO earth station and the nth LEO earth station.

[0116] The expected interference E(I) and the distance r between the GEO earth station and the LEO earth station are both functions of n. Therefore, the relationship between the expected interference E(I) and the protection radius R 0 can be obtained through the intermediate variable n. Through the interference threshold, the boundary value of the protection radius in the downlink can be obtained.

[0117] In the first embodiment of the present invention, two different LEO satellite altitude values are set, and the relationship between the satellite altitude and the expected value of interference can be analyzed.

[0118] Taking the following downlink as an example, the specific parameter settings for the simulation are shown in Table 1 below.

[0119] Table 1 Downlink Parameters

[0120]

[0121] The method expression proposed by the present invention is simple and easy to analyze. It innovatively uses the Fibonacci grid method to represent satellite coordinates, can quickly calculate the interference expectation value, and has higher efficiency.

[0122] The example of the present invention analyzes the influence of different LEO satellite heights on the interference expectation value of the GEO earth station. From Figure 6 The change curve graph of the interference expectation value and the protection radius in the downlink, it can be seen that in the downlink, the higher the LEO satellite height, the greater the interference expectation value, indicating that the GEO earth station is more interfered. The example of the present invention gives the specific value of the protection radius, which can provide a certain reference for the layout of LEO earth stations. From Figure 6 It can be known that when the LEO satellite height is 750 km, the protection radius is 413 km, which means that when laying out LEO earth stations, it should be located outside the circle with the GEO earth station as the center and a radius of 413 km, so as to ensure that the GEO system is not interfered and the normal communication ability of the GEO system is guaranteed.

[0123] Embodiment Two

[0124] In this Embodiment Two, taking the uplink as an example, referring to the downlink analysis method, the interference expression of the satellite uplink is derived by establishing the interference scenario and the spatial position model of the interfering earth station of the uplink. The interference expectation value is calculated by adding up the interference values of each link and dividing by the total number of interfering earth stations. The protection radius is determined according to the interference threshold, and further the interference protection area is determined.

[0125] In Embodiment Two of the present invention, two different LEO satellite height values are set, and the relationship between the satellite height and the interference expectation value can be analyzed. Taking the uplink as an example, the specific parameter settings for the simulation are shown in Table 2 below.

[0126] Table 2 Uplink Parameters

[0127]

[0128] Figure 7The figure shows the curve of the change in the expected interference value and the protection radius in the uplink provided by an embodiment of the present invention. It can be seen that in the uplink, the higher the altitude of the LEO satellite, the greater the expected interference value, indicating that the GEO satellite is more severely interfered. When the altitude of the LEO satellite is 950 km, the protection radius is 400 km, which means that when deploying the LEO earth station, it should be located outside the circle with the GEO earth station as the center and a radius of 400 km.

[0129] It can be seen that the method for defining the protection area of the GEO earth station to avoid interference from large-scale LEO constellations provided by the present invention is based on a three-dimensional space model. The Fibonacci grid method can be used to quickly approximate the coordinates of the satellites, further obtain the cumulative interference power of the GEO system, quickly write the expression of the expected interference, and obtain the curve of the change in the expected interference and the protection radius. The boundary value of the protection radius can be determined by the threshold, and then the interference protection area can be further determined. The calculation expression is simple and easy to analyze, greatly reducing the complexity, and providing a reference for the deployment of LEO earth stations.

[0130] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, rather than limiting the implementation manners of the present invention. For those of ordinary skill in the art, other different forms of changes or modifications can be made based on the above description. It is impossible to list all the implementation manners here. Any obvious changes or modifications derived from the technical solutions of the present invention still fall within the protection scope of the present invention.

Claims

1. A method for defining the protection area range of a GEO earth station to avoid interference from a large-scale LEO constellation, characterized in that, it includes the following steps: S01: Calculate the threshold of the interference expected value according to the outage probability of the GEO communication system; S02: Establish a protection area model and set a protection radius, construct an interference scenario model according to the protection radius, and determine the calculation formula for the interference of the LEO satellite on the GEO earth station; S03: Use the Fibonacci grid method to obtain the satellite spatial position coordinates in the interference scenario model; S04: Based on the calculation formula for the interference of the LEO satellite on the GEO earth station and the satellite spatial position coordinates, determine the calculation formula for the interference expected value; S05: According to the threshold of the interference expected value and the calculation formula for the interference expected value, determine the protection boundary radius value of the protection area, and then determine the protection area range; In step S01, the threshold of the interference expected value is calculated based on the following formula: N GEO = KTW; Among them, E(I) is the expected value of interference, ε is the outage probability, 0 ≤ ε ≤ 1, P GEO is the received power of the GEO system, C 0 is the minimum transmission rate required to ensure the normal communication of the GEO communication system, N GEO is the noise of the GEO system, K is the Boltzmann constant, T is the noise temperature of the GEO system, and W is the bandwidth; In step S02, the calculation formula for the interference I of the LEO satellite on the GEO earth station is determined as: Among them, I is the interference of the LEO satellite to the GEO earth station, and P ns is the transmit power of the LEO satellite, Gns(θ 2 ) is the antenna gain of the LEO satellite in the θ 2 direction, G es (θ 1 ) is the antenna gain of the GEO earth station in the θ 1 direction, c is the speed of light, f is the center frequency of the spectrum, d is the distance between the LEO satellite and the GEO earth station, and φ k is the Rice parameter; In step S03, the satellite spatial position coordinates are: where R e is the radius of the earth, H leo is the altitude of the LEO satellite, n is the serial number, m is the serial number when the GEO earth station and the LEO satellite are just visible, N is the total number of LEO satellites, and φ is the golden ratio; In step S04, the calculation formula for the interference expected value is determined as; Among them, E(I) is the expected value of interference, P ns is the transmission power of the LEO satellite, G ns (θ 2n ) is the antenna gain of the LEO satellite in the θ 2n direction, G es (θ 1n ) is the antenna gain of the GEO earth station in the θ 1n direction, c is the speed of light, f is the center frequency of the spectrum, d n is the distance between the GEO earth station and the nth LEO satellite, φ k is the Rice parameter, m is the serial number when the GEO earth station and the LEO satellite are just visible, N is the total number of LEO satellites, H geo is the altitude of the GEO satellite, θ 1n is the off-axis angle of the GEO earth station in the direction of the nth LEO satellite, θ 2n is the off-axis angle of the nth LEO satellite in the direction of the GEO earth station; In step S05, the protection boundary radius value R of the protection area 0 is as follows: Among them, R e is the radius of the earth, and ν n represents the central angle between the GEO earth station and the nth LEO earth station.

2. The method for defining the protection area range of a GEO earth station to avoid interference from a large-scale LEO constellation according to claim 1, characterized in that, when the distance between the LEO earth station and the GEO earth station is greater than the protection boundary radius value, the LEO satellite will not cause interference to the GEO satellite system.

3. The method for defining the protection area range of a GEO earth station to avoid interference from a large-scale LEO constellation according to claim 1, characterized in that, the interference scenario model is established based on the satellite downlink.

4. The method for defining the protection area range of a GEO earth station to avoid interference from a large-scale LEO constellation according to claim 1, characterized in that, the interference scenario model is established based on the satellite uplink.

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