Method, device and user terminal for selecting user access platform of space-air fusion network

Abstract

The present invention discloses a method, device and user terminal for selecting a user access platform for an air-space fusion network, relates to the technical field of air-space fusion networks, and solves the technical problem of "how to select an access platform taking into account the different performances of the main-side lobe areas of the air-space platform". The method comprises: calculating a first probability that a user terminal falls into the main lobe area of ​​the air-space platform, and a second probability that the user terminal falls into the side lobe area of ​​the air-space platform; calculating a first system capacity of the air-space platform in the main lobe area, and a second system capacity of the air-space platform in the side lobe area; calculating the average system capacity of each air-space platform according to the first probability, the second probability, the first system capacity and the second system capacity; selecting the air-space platform with the largest average system capacity as the user terminal access platform; the method can take into account the different antenna gains in the main-side lobe areas of satellites and aircraft, so as to maximize the user terminal system capacity.

Description

Technical Field

[0001] The present invention relates to the technical field of space-air fusion network. Background Art

[0002] One of the main goals of 6G is to expand the coverage of traditional ground cellular networks through the integration of space, air and ground networks. In some remote areas, due to the imperfect ground infrastructure, there is a lack of ground cellular network coverage. As normalized infrastructure, low-orbit satellites in space-based platforms and civil aircraft in air-based platforms can provide supplementary coverage for ground users.

[0003] Before the space-air fusion network provides formal commercial services to ground users, it is necessary to analyze the performance of the heterogeneous networks where these space-air platforms are located, and propose a platform selection plan for users to achieve greater system capacity at a lower cost. Due to the existence of different types of access platforms in the space-air fusion network, and the complex channel conditions from space-based and air-based nodes to ground users, it is very difficult for users to choose the type of non-ground network. At the same time, since the downlink beams of satellites and aircraft are divided into main lobe and side lobe areas, the different areas where users are located in the space-air platform will further affect the system performance and access selection. However, in the existing research work, a general system capacity analysis method has not been proposed for the above-mentioned scenarios unique to the space-air fusion network. Therefore, how to take into account the different system capacity performance of the main and side lobe areas of satellites and aircraft and select the access platform in the space-air network at the user end has become a technical problem that needs to be solved urgently in this field. Summary of the invention

[0004] In order to solve the technical problems existing in the prior art, the present invention provides a method, device and system for selecting a user access platform for an air-space fusion network, which can take into account the different antenna gains in the main sidelobe areas of satellites and aircraft to maximize the user-side system capacity.

[0005] A method for selecting a user access platform for an air-space fusion network, comprising:

[0006] Acquire a topological structure and communication parameters of an air-space fusion network, wherein the air-space fusion network includes a plurality of air-space platforms;

[0007] Calculate a first probability that the user terminal falls into a main lobe region of the aerospace platform, and a second probability that the user terminal falls into a side lobe region of the aerospace platform;

[0008] Calculate a first system capacity of the aerospace platform in a main lobe region and a second system capacity of the aerospace platform in a side lobe region;

[0009] Calculate the average system capacity of each aerospace platform according to the first probability, the second probability, the first system capacity, and the second system capacity;

[0010] Select the aerospace platform with the largest average system capacity as the user-side access platform.

[0011] Furthermore, the topology structure includes the number of aircraft, the number of satellites, the aircraft flight altitude, the satellite orbit altitude, and the distance between the user terminal and the aerospace platform, and the communication parameters include the minimum communication opening angle, transmission power, fading scenario, communication frequency, aerospace platform antenna main lobe gain, and aerospace platform antenna side lobe gain.

[0012] Furthermore, the fading scenario is described using a Rice-shadow fading model.

[0013] Furthermore, after obtaining the topological structure and communication parameters of the aerospace network, the boundary distance and area division in the aerospace platform are calculated, including:

[0014] Calculate the visible boundary distance of the aerospace platform;

[0015] According to the visible boundary distance, the visible area distribution of the aerospace platform is obtained;

[0016] Calculate the main lobe and side lobe boundary distances of the aerospace platform main lobe area and side lobe area;

[0017] According to the main-side lobe boundary distance, the main lobe area distribution of the air-space network is obtained.

[0018] Furthermore, before calculating the first probability and the second probability, the method further includes calculating a distribution function of the distance distribution between the aerospace platform and the user terminal, which specifically includes:

[0019] Based on the distance between the user terminal and the aerospace platform, the aircraft and satellite closest to the user terminal in the visible area are selected as the service aerospace platform;

[0020] Based on the visible boundary distance, a first distribution function of the distance between the user terminal and the aerospace platform is calculated;

[0021] Based on the first distribution function, a second distribution function of the distance between the user terminal and the service aerospace platform is calculated;

[0022] Based on the second distribution function, a third distribution function of the distance between the user terminal and each aerospace platform is calculated when the service aerospace platform is located in the main lobe area;

[0023] Based on the second distribution function, a fourth distribution function of the distance between the user terminal and each aerospace platform is calculated when the serving aerospace platform is located in the sidelobe area.

[0024] Furthermore, the third distribution function is calculated by the following formula:

[0025] when

[0026] The fourth distribution function is calculated by the following formula:

[0027] when

[0028] Among them, j∈{CA,SAT} represents the type of aerospace platform, CA represents aircraft, SAT represents satellite, is the second distribution function of the distance between the user terminal and the service space platform, H j is the flight altitude of the aerospace platform in the aerospace fusion network, The boundary distance between the main lobe and side lobe services in the space-air fusion network, is the visible boundary distance in the air-space fusion network.

[0029] Furthermore, the first probability is calculated by the following formula:

[0030]

[0031] The second probability is calculated by the following formula:

[0032]

[0033]

[0034] Among them, d j,0 is the distance between the user terminal and the nearest aerospace platform when the user terminal accesses the aerospace fusion network, is the total area of ​​all aerospace platforms in the aerospace integration network. is the visible area of ​​the aerospace platform, P void (·) is the probability that the set is empty, S(x) is the area of ​​the given region, The main lobe area.

[0035] Furthermore, the first system capacity is calculated by the following formula:

[0036]

[0037] The second system capacity is calculated by the following formula:

[0038]

[0039]

[0040] The average system capacity is calculated by the following formula:

[0041]

[0042] Among them, SNRj is the signal-to-interference-and-noise ratio received by the user end, is the main lobe gain of the aerospace platform antenna, is the sidelobe gain of the aerospace platform antenna, is the probability density function of the distance between the user terminal and each aerospace platform when the service aerospace platform is located in the main lobe area, is the probability density function of the distance between the user terminal and each aerospace platform when the service aerospace platform is located in the sidelobe area, X j,0 Y represents the distance between the user terminal and the nearest space platform when the user terminal is located in the main lobe area of ​​the service platform when the user terminal accesses the space-space fusion network. j,0 It represents the distance between the user terminal and the nearest aerospace platform when the user terminal is located in the sidelobe area of ​​the serving aerospace platform when the user terminal accesses the aerospace fusion network, d j,0 is the distance between the user terminal and the nearest aerospace platform when the user terminal accesses the aerospace fusion network, G R is the receiving antenna gain of the user end, p j is the transmission power of the aerospace platform, L AL,j is the constant additional loss caused by environmental factors, λ j is the wavelength and α is the path loss exponent.

[0043] A device for selecting a user access platform for an air-space fusion network, comprising:

[0044] A parameter acquisition module, used to acquire the topology structure and communication parameters of an air-space fusion network, wherein the air-space fusion network includes multiple air-space platforms;

[0045] A main-sidelobe probability calculation module, used to calculate a first probability that a user terminal falls into the mainlobe area of ​​the aerospace platform, and a second probability that a user terminal falls into the sidelobe area of ​​the aerospace platform;

[0046] A main-sidelobe system capacity calculation module, used to calculate a first system capacity of the aerospace platform in a mainlobe region, and a second system capacity of the aerospace platform in a sidelobe region;

[0047] an average system capacity calculation module, used to calculate the average system capacity of each aerospace platform according to the first probability, the second probability, the first system capacity and the second system capacity;

[0048] The platform selection module is used to select the aerospace platform with the largest average system capacity as the user-side access platform.

[0049] A mobile communication user terminal is applied to realize communication in an air-space fusion network, wherein the air-space fusion network includes at least one satellite and at least one aircraft. The user terminal includes a processor and a storage device, wherein the storage device stores multiple instructions, and the processor is used to read the multiple instructions in the storage device and execute the above method.

[0050] The method, device and system for selecting a user access platform for an air-space integrated network provided by the present invention have at least the following beneficial effects:

[0051] (1) Taking into account the different antenna gains in the main sidelobe regions of satellites and aircraft, the calculation and weighted summation are discussed and calculated according to the different positional relationships between the user end and the aerospace platform to maximize the user end system capacity;

[0052] (2) The research on the space-air fusion network is based on the Rice-Shadow Fading Model, which is more suitable for the small-scale fading scenario of the communication link from the user end to the space-air platform, and the analysis results are closer to the actual situation;

[0053] (3) Through the network topology structure and various communication parameters, the occurrence probability and system capacity of different networks in the position relationship are calculated. It can quantitatively represent the change trend of the average system capacity corresponding to the two network types with respect to each parameter, and accurately compare and select the solution that maximizes the system capacity. BRIEF DESCRIPTION OF THE DRAWINGS

[0054] Figure 1 A flow chart of an embodiment of a method for selecting a user access platform for an air-space fusion network provided by the present invention;

[0055] Figure 2 A schematic diagram of the network architecture of an embodiment of the air-space fusion network in the method provided by the present invention;

[0056] Figure 3 A flow chart of another embodiment of the method for selecting a user access platform for an air-space fusion network provided by the present invention;

[0057] Figure 4 A schematic diagram of the structure of an embodiment of satellite network distribution in the method provided by the present invention;

[0058] Figure 5 A structural schematic diagram of an embodiment of aircraft network distribution in the method provided by the present invention;

[0059] Figure 6 The relationship between the system capacity of the user terminal in the satellite network and the minimum communication angle in the method provided by the present invention;

[0060] Figure 7 The relationship between the system capacity of the user terminal in the aircraft network and the minimum communication beam angle in the method provided by the present invention;

[0061] Figure 8 The relationship between the system capacity and the transmission power of the user terminal in the satellite network in the method provided by the present invention;

[0062] Fig. 9The relationship between the system capacity and the transmission power of the user terminal in the aircraft network in the method provided by the present invention;

[0063] Figure numerals: 1-satellite, 2-aircraft, 3-user terminal, 4-satellite ground station, 5-aircraft gateway, 6-feeder link, 7-useful signal from the service aerospace platform. DETAILED DESCRIPTION

[0064] In order to better understand the above technical solution, the above technical solution will be described in detail below in conjunction with the accompanying drawings and specific implementation methods.

[0065] The space-air fusion network includes two types of space-air platforms, namely, aircraft and satellites, each of which constitutes a layer of network, and each layer of network includes multiple aircraft or satellites. Among them, the aircraft adopts a civil aircraft. Through the method provided in this embodiment, the ground user terminal can intelligently switch the access network and select the visible space-air platform closest to the user terminal in a certain layer of network as the service space-air platform to provide services for it.

[0066] This embodiment mainly analyzes the system capacity of the air-space fusion network under the SR fading scenario, and designs a platform selection method for ground users with the goal of maximizing the receiving end system capacity. Considering that remote areas, such as remote villages, oceans, forests, etc., are usually not covered by ground cellular networks, in order to meet the communication needs of users in these areas, satellites and aircraft over the area can be used for auxiliary communication.

[0067] refer to Figure 1 In some embodiments, a method for selecting a user access platform for an air-space fusion network is provided, comprising:

[0068] S1. Obtain the topological structure and communication parameters of the space-air fusion network, where the space-air fusion network includes multiple space-air platforms;

[0069] S2, calculating a first probability that the user terminal falls into the main lobe area of ​​the aerospace platform, and a second probability that the user terminal falls into the side lobe area of ​​the aerospace platform;

[0070] S3, calculating a first system capacity of the aerospace platform in a main lobe region, and a second system capacity of the aerospace platform in a side lobe region;

[0071] S4. Calculate the average system capacity of each aerospace platform according to the first probability, the second probability, the first system capacity, and the second system capacity;

[0072] S5. Select the aerospace platform with the largest average system capacity as the user-side access platform.

[0073] refer to Figure 2, showing a downlink space-air fusion network scenario without cellular network coverage. In a specific application scenario, there are C aircraft and S satellites in the space-air fusion network, and users provide services for specific handheld user terminals on the ground. Let j∈{CA,SAT} represent the type of space-air platform. CA represents aircraft and SAT represents satellite. Satellites are uniformly distributed in a radius of H. SAT +R E The sphere is evenly distributed according to the binomial point process (BPP), where H SAT and R E Denote the satellite orbit height and the earth radius respectively. The satellite set is denoted by s∈V SAT ={0,...,S-1}, where the satellite closest to the user is the service satellite with index 0, and the satellite farthest from the user is indexed as S-1. Correspondingly, since the distribution of aircraft in different regions and at different times varies greatly, it is assumed that the aircraft is within a radius of R CA The disks are uniformly distributed according to the BPP. The set of planes is represented by c∈V CA ={0,...,C-1} means that the aircraft closest to the user is the service aircraft, with an index number of 0, and the aircraft farthest from the user is numbered C-1.

[0074] The user end has a receiving antenna gain of G R The omnidirectional antenna of the aerospace platform is deployed with a conical aperture antenna. For theoretical analysis, the aerospace platform adopts a partitioned antenna beam pattern. The antenna gain of the j-type network aerospace platform is divided into main lobe gain and side lobe gain, which are expressed as and make represents the steering angle between the link from the user end to the aerospace platform and the visual axis direction of the aerospace platform i, let is the threshold angle between the main lobe and side lobe of the j-type network aerospace platform. SAT ∪V CA When within the user's visible range, the transmitting antenna gain of the aerospace platform can be expressed as

[0075]

[0076] in, is the main lobe gain of the aerospace platform antenna, is the sidelobe gain of the aerospace platform antenna, is the steering angle between the link from the user end to the aerospace platform and the line of sight direction of the aerospace platform i.

[0077] It should be noted that the fading scenario is described by the Rice-Shadow fading model. In the existing solutions, when analyzing the traditional ground network, the small-scale fading models used are mostly Nakagami-m fading or Rayleigh fading. Rice-Shadow (SR) fading is a small-scale fading model suitable for space-to-ground and space-to-ground channels. It is a general model for small-scale fading of the communication link from the user to the space platform. It is described by the following parameters: Let SR (Ω j ,b j ,m j ) represents the SR fading coefficient in the j-type network, where Ω j is the average power component at line of sight, 2b j is the average power of the scattered component, m j It is the Nakagami parameter.

[0078] Specifically, in step S1, the topological structure includes the number of aircraft, the number of satellites, the aircraft flight altitude, the satellite orbit altitude, and the distance between the user terminal and the aerospace platform, and the communication parameters include the minimum communication angle, transmission power, fading scenario, communication frequency, aerospace platform antenna main lobe gain, and aerospace platform antenna side lobe gain.

[0079] The transmit power is used to calculate the signal-to-interference-to-noise ratio at the user receiving end, which is expressed by the following formula:

[0080]

[0081]

[0082] Among them, p j is the transmission power of the aerospace platform, L FL,j,0 is the free space path loss between the user terminal and the aerospace platform i, where λ j is the wavelength, d j,i represents the distance between the user terminal and the space platform i of the j-type network, α is the path loss index, and L AL,j is the constant additional loss caused by environmental factors, h j,0 is the channel gain between the space platform 0 (service space platform) and the user in the j-type network, G R is the receiving antenna gain of the user end, σ is the arithmetic square root of the noise power, G T,j,0 It is the transmitting antenna gain of the aerospace platform closest to the user terminal when the user terminal accesses the aerospace fusion network.

[0083] h j,i represents the channel gain between the space platform i and the user of the j-type space network, and its distribution function is expressed as:

[0084]

[0085] Among them, 1F1(·,·,·) is the Kummer fused hypergeometric function, γ(·) is the lower bound incomplete Gamma function, (·) k is the Pochhammer symbol, Ω j is the average power component at line of sight, 2b j is the average power of the scattered component, m j is the Nakagami parameter, and h is the small-scale fading variable in shadow-Rician fading.

[0086] refer to Figure 3 In some embodiments, after obtaining the topological structure and communication parameters of the aerospace network, it also includes: calculating the boundary distance and area division in the aerospace platform, which specifically includes the following steps:

[0087] (1) Calculate the visible boundary distance of the aerospace platform;

[0088] (2) Obtain the visible area distribution of the aerospace platform based on the visible boundary distance;

[0089] (3) Calculate the main lobe and side lobe boundary distances of the aerospace platform main lobe area and side lobe area;

[0090] (4) According to the main lobe and side lobe boundary distance, the main lobe area distribution of the aerospace network is obtained.

[0091] The visible area of ​​the aerospace platform and the main lobe area of ​​the aerospace network calculated in step S12 and step S14 are used for the probability calculation of the user terminal falling into the main side lobe area of ​​the aerospace platform in the subsequent steps. The calculation process of steps S11-S14 in the satellite network and the aircraft network are introduced below.

[0092] refer to Figure 4 , in satellite networks, according to the law of cosines, equation holds, where θ SAT,min is the minimum communication beam angle of the satellite network, is the visible boundary distance in the satellite network.

[0093] Therefore, the visible boundary distance of the satellite is calculated by the following formula:

[0094]

[0095] The distribution size of the satellite's visible area is calculated by the following formula:

[0096]

[0097] Among them, θ SAT,min is the minimum communication beam angle of the satellite network, is the visible boundary distance in the satellite network, H SAT and R E represent the satellite orbit altitude and the earth radius respectively.

[0098] Similarly, the boundary distances between the main lobe and side lobe services in a satellite network are Calculated by the following formula:

[0099]

[0100] The satellite network main lobe area distribution size is calculated by the following formula:

[0101]

[0102] in, is the threshold angle between the main lobe and side lobe of the satellite network.

[0103] refer to Figure 5 , in the aircraft network, based on the set relationship, we can get H CA cscθ CA,min In addition, the boundary distance of the user within the aircraft main lobe can be expressed as The visible range of the aircraft and the size of the area served by the main lobe are and Among them, θ CA,min is the minimum communication angle of the aircraft network, d CA,c is the distance between the user terminal and aircraft c in the aerospace fusion platform aircraft network.

[0104] refer to Figure 3 In some embodiments, in step S3, before calculating the first system capacity of the aerospace platform in the main lobe area and the second system capacity of the aerospace platform in the side lobe area, it also includes calculating the distribution function of the distance distribution between the aerospace platform and the user terminal, which specifically includes the following steps:

[0105] S31. Based on the distance between the user terminal and the aerospace platform, select the aircraft and satellite closest to the user terminal in the visible area as the service aerospace platform;

[0106] S32, calculating a first distribution function of the distance between the user terminal and the aerospace platform;

[0107] S33. Calculate a second distribution function of the distance between the user terminal and the service aerospace platform based on the first distribution function;

[0108] S34. Calculate, based on the second distribution function, a third distribution function of the distance between the user terminal and each aerospace platform when the service aerospace platform is located in the main lobe area;

[0109] S35. Based on the second distribution function, calculate a fourth distribution function of the distance between the user terminal and each aerospace platform when the service aerospace platform is located in the sidelobe area.

[0110] The distribution function calculated in steps S32-S35 is used in subsequent steps to calculate the system capacity in the main lobe area and the side lobe area.

[0111] Specifically, the first distribution function of the distance between the user terminal and any aerospace platform in the aerospace fusion network is expressed as:

[0112]

[0113] Among them, H j is the flight altitude of the aerospace platform in the aerospace fusion network, is the visible boundary distance in the satellite network, is the visible boundary distance in the aircraft network, H SAT and R E represent the satellite orbit altitude and the earth radius respectively.

[0114] The second distribution function of the distance between the user terminal and the service space platform in the space-space fusion network is expressed as:

[0115] when

[0116] Among them, |V j | is the set V j The number of elements in , is the visible boundary distance in the air-space fusion network.

[0117] When the service aerospace platform is located in the main lobe area, the third distribution function of the distance between the user terminal and each aerospace platform is expressed as:

[0118] when

[0119] in, The boundary distance of the main lobe and side lobe services in the space-air fusion network.

[0120] When the service aerospace platform is located in the sidelobe area, the fourth distribution function of the distance between the user terminal and each aerospace platform is expressed as:

[0121] when

[0122] in, The boundary distance between the main lobe and side lobe services in the space-air fusion network, is the visible boundary distance in the air-space fusion network.

[0123] The above distribution functions are differentiated respectively to obtain the corresponding probability density function.

[0124] When studying the location of the user end in the main lobe area or side lobe area of ​​the aerospace platform, the positional relationship between the user end and the service aerospace platform is divided into three cases:

[0125] (1) The user is in the main lobe area of ​​the service aerospace platform;

[0126] (2) Users are in the sidelobe area of ​​the service aerospace platform;

[0127] (3) There is no service space platform.

[0128] The probability of no service space platform is Where P void (·) is the probability that the set is empty, which can be expressed as Where S(x) is the area of ​​the given region.

[0129] Further, in step S2, the first probability that the user terminal falls into the main lobe area of ​​the aerospace platform is calculated by the following formula:

[0130]

[0131] The second probability that the user terminal falls into the sidelobe area of ​​the aerospace platform is calculated by the following formula:

[0132]

[0133]

[0134] Among them, d j,0 is the distance between the user terminal and the nearest aerospace platform when the user terminal accesses the aerospace fusion network, is the total area of ​​all aerospace platforms in the aerospace integration network. is the visible area of ​​the aerospace platform, P void (·) is the probability that the set is empty, S(x) is the area of ​​the given region, The main lobe area.

[0135] Based on the third distribution function, the first system capacity of the aerospace platform in the main lobe area is calculated and expressed by the following formula:

[0136]

[0137] The second system capacity of the aerospace platform in the sidelobe area is calculated by the following formula:

[0138]

[0139]

[0140] The average system capacity is calculated using the following formula:

[0141]

[0142] Among them, SNR j is the signal-to-interference-and-noise ratio received by the user end, is the main lobe gain of the aerospace platform antenna, is the sidelobe gain of the aerospace platform antenna, is the probability density function of the distance between the user terminal and each aerospace platform when the service aerospace platform is located in the main lobe area, which is obtained by derivation of the third distribution function. is the probability density function of the distance between the user terminal and each aerospace platform when the service aerospace platform is located in the sidelobe area, which is obtained by derivation of the fourth distribution function, X j,0 Y represents the distance between the user and the nearest platform when the user terminal accesses the space-air fusion network and is located in the main lobe area of ​​the serving space-air platform. j,0 It represents the distance between the user terminal and the nearest aerospace platform when the user terminal is located in the sidelobe area of ​​the serving aerospace platform when the user terminal accesses the aerospace fusion network, d j,0 is the distance between the user terminal and the nearest aerospace platform when the user terminal accesses the aerospace fusion network, G R is the user receiving antenna gain, p j is the transmission power of the aerospace platform, L AL,j is the constant additional loss caused by environmental factors, λ j is the wavelength and α is the path loss exponent.

[0143] In step S5, in order to achieve the goal of maximizing the user-side system capacity, the user chooses to access the network that can provide the maximum system capacity, that is: In addition, a visible aerospace platform closest to the user terminal is selected in the network as a service aerospace platform to provide services to the user terminal.

[0144] In a specific simulation scenario, the results of theoretical analysis and simulation analysis are compared to verify the correctness of the theoretical analysis. Consider three fading scenarios: frequent heavy shadowing (FHS), infrequent light shadowing (ILS), and average shadowing (AS). The corresponding SR fading parameters are: FHS (b j =0.063,m j =0.739,Ω j =8.97×10 -4 ), ILS(b j =0.158,mj =19.4,Ω j =1.29), AS(b j =0.126,m j =10.1,Ω j =0.835).

[0145] The following simulation experiment uses the Monte Carlo method, the number of aircraft is 60, the radius of the disk area where the aircraft are distributed is 100km, and the number of satellites is 1584. The parameter settings used in the simulation are shown in Table 1.

[0146] Table 1 Simulation parameter settings

[0147]

[0148] See also Figure 6 and Figure 7 , respectively, are the relationship between the satellite network and aircraft network system capacity and the minimum communication elevation angle. The figure uses the achievable rate to represent the system capacity. It can be found that each curve shows a trend of first rising and then falling. The reason for this phenomenon is that when the minimum communication elevation angle is small, as the communication elevation angle increases, the channel condition of the aerospace platform-user communication link is better, thereby improving the system capacity. However, when the communication elevation angle increases to a certain extent, the number of aerospace platforms within the user's visible range will decrease, thereby reducing the system capacity. In addition, among the three fading scenarios, ILS has the best performance and FHS has the worst performance.

[0149] See also Figure 8 and Fig. 9 , respectively, are the relationship between the satellite network and aircraft network system capacity and the aerospace platform transmission power. The figure uses the achievable rate to represent the system capacity. It can be found that with the increase of transmission power, all curves show an upward trend due to the increase of useful signals. By comparing satellite and aircraft networks, it can be found that in order to achieve similar system capacity, the transmission power required by the aircraft is much smaller than that of the satellite network.

[0150] In existing research, there is a lack of quantitative research on the system capacity of aircraft networks and satellite networks. Based on the above simulation experiments, it can be seen that in most cases, the aircraft network in the air-space fusion network can achieve a system capacity similar to that of the satellite network. In addition, in order to achieve a similar system capacity, the transmission power required by the aircraft network is much smaller than that of the satellite network. Therefore, when supplementing coverage in remote areas that lack ground cellular network coverage, the integration of aircraft networks and satellite networks is better than using only satellite networks. Furthermore, by Figure 5-8It can be seen that the system capacities of the aircraft network and the satellite network vary due to changes in topology and communication parameters. The method provided in this embodiment can determine the system capacity of the two networks at the user end and then select the best one, which can well achieve the goal of maximizing the system capacity of the user end.

[0151] In some embodiments, a device for selecting a user access platform for an air-space fusion network is provided, comprising:

[0152] A parameter acquisition module, used to acquire the topology structure and communication parameters of the space-air fusion network, where the space-air fusion network includes multiple space-air platforms;

[0153] A main-sidelobe probability calculation module, used to calculate a first probability that the user terminal falls into the mainlobe area of ​​the aerospace platform, and a second probability that the user terminal falls into the sidelobe area of ​​the aerospace platform;

[0154] A main-sidelobe system capacity calculation module, used to calculate the first system capacity of the aerospace platform in the mainlobe area, and the second system capacity of the aerospace platform in the sidelobe area;

[0155] An average system capacity calculation module, used to calculate the average system capacity of each aerospace platform according to the first probability, the second probability, the first system capacity and the second system capacity;

[0156] The platform selection module is used to select the aerospace platform with the largest average system capacity as the user-side access platform.

[0157] In some embodiments, a mobile communication user terminal is provided, which is applied to an air-space fusion network to realize communication. The air-space fusion network includes at least one satellite and at least one aircraft. The user terminal includes a processor and a storage device. The storage device stores multiple instructions. The processor is used to read the multiple instructions in the storage device and execute the above method.

[0158] The method, device and system for selecting a user access platform for an aerospace fusion network provided in this embodiment take into account the different antenna gains in the main sidelobe regions of satellites and aircraft, discuss and calculate according to different positional relationships between the user terminal and the aerospace platform, and perform weighted summation to maximize the system capacity of the user terminal; the aerospace fusion network is studied based on the Rice-shadow fading model, which is more suitable for small-scale fading scenarios of communication links from the user terminal to the aerospace platform, and the analysis results are closer to the actual situation; the occurrence probability and system capacity of different networks in the positional relationship are calculated through the network topology structure and a variety of communication parameters, which can quantitatively represent the changing trends of the average system capacity corresponding to the two network types with respect to each parameter, and accurately compare and select the solution that maximizes the system capacity.

[0159] Although preferred embodiments of the present invention have been described, additional changes and modifications may be made to these embodiments by those skilled in the art once the basic inventive concepts are known. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications that fall within the scope of the present invention. Obviously, those skilled in the art may make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include these modifications and variations.

Claims

1. A method for selecting a user access platform for an air-space fusion network, characterized in that: include: Acquire a topological structure and communication parameters of an air-space fusion network, wherein the air-space fusion network includes a plurality of air-space platforms; Calculate a first probability that the user terminal falls into a main lobe region of the aerospace platform, and a second probability that the user terminal falls into a side lobe region of the aerospace platform; Calculate a first system capacity of the aerospace platform in a main lobe region and a second system capacity of the aerospace platform in a side lobe region; Calculate the average system capacity of each aerospace platform according to the first probability, the second probability, the first system capacity, and the second system capacity; Select the aerospace platform with the largest average system capacity as the user-side access platform; The first probability is calculated by the following formula: The second probability is calculated by the following formula: Among them, d j,0 is the distance between the user terminal and the nearest aerospace platform when the user terminal accesses the aerospace fusion network, is the total area of ​​all aerospace platforms in the aerospace integration network. is the visible area of ​​the aerospace platform, P void (·) is the probability that the set is empty, S(x) is the area of ​​the given region, is the main lobe area; The first system capacity is calculated by the following formula: The second system capacity is calculated by the following formula: The average system capacity is calculated by the following formula: Among them, SNR j is the signal-to-interference-and-noise ratio received by the user end, is the main lobe gain of the aerospace platform antenna, is the sidelobe gain of the aerospace platform antenna, is the probability density function of the distance between the user terminal and each aerospace platform when the service aerospace platform is located in the main lobe area, is the probability density function of the distance between the user terminal and each aerospace platform when the service aerospace platform is located in the sidelobe area, X j,0 Y represents the distance between the user terminal and the nearest aerospace platform when the user terminal is located in the main lobe area of ​​the serving aerospace platform when the user terminal accesses the aerospace fusion network. j,0 It represents the distance between the user terminal and the nearest aerospace platform when the user terminal is located in the sidelobe area of ​​the serving aerospace platform when the user terminal accesses the aerospace fusion network, d j,0 is the distance between the user terminal and the nearest aerospace platform when the user terminal accesses the aerospace fusion network, G R is the receiving antenna gain of the user end, p j is the transmission power of the aerospace platform, L AL,j is the constant additional loss caused by environmental factors, λ j is the wavelength, α is the path loss exponent, H j is the flight altitude of the aerospace platform in the aerospace fusion network, The boundary distance between the main lobe and side lobe services in the space-air fusion network, is the visible boundary distance in the air-space fusion network.

2. The method according to claim 1, characterized in that The topological structure includes the number of aircraft, the number of satellites, the aircraft flight altitude, the satellite orbit altitude, and the distance between the user terminal and the aerospace platform. The communication parameters include the minimum communication opening angle, transmission power, fading scenario, communication frequency, aerospace platform antenna main lobe gain, and aerospace platform antenna side lobe gain.

3. The method according to claim 2, characterized in that The fading scenario is described using the Rice-shadow fading model.

4. The method according to claim 1, characterized in that: After obtaining the topological structure and communication parameters of the aerospace network, it also includes calculating the boundary distance and area division in the aerospace platform, including: Calculate the visible boundary distance of the aerospace platform; According to the visible boundary distance, the visible area distribution of the aerospace platform is obtained; Calculate the main lobe and side lobe boundary distances of the aerospace platform main lobe area and side lobe area; According to the main-side lobe boundary distance, the main lobe area distribution of the air-space network is obtained.

5. The method according to claim 4, characterized in that Before calculating the first probability and the second probability, the method further includes calculating a distribution function of the distance distribution between the aerospace platform and the user terminal, specifically including: Based on the distance between the user terminal and the aerospace platform, the aircraft and satellite closest to the user terminal in the visible area are selected as the service aerospace platform; Based on the visible boundary distance, a first distribution function of the distance between the user terminal and the aerospace platform is calculated; Based on the first distribution function, a second distribution function of the distance between the user terminal and the service aerospace platform is calculated; Based on the second distribution function, a third distribution function of the distance between the user terminal and each aerospace platform is calculated when the service aerospace platform is located in the main lobe area; Based on the second distribution function, a fourth distribution function of the distance between the user terminal and each aerospace platform is calculated when the serving aerospace platform is located in the sidelobe area.

6. The method according to claim 5, characterized in that The third distribution function is calculated by the following formula: The fourth distribution function is calculated by the following formula: Among them, j∈{CA,SAT} represents the type of aerospace platform, CA represents aircraft, SAT represents satellite, It is the second distribution function of the distance between the user terminal and the service aerospace platform.

7. A device for selecting a user access platform for an air-space fusion network, characterized in that: include: A parameter acquisition module, used to acquire the topology structure and communication parameters of an air-space fusion network, wherein the air-space fusion network includes multiple air-space platforms; A main-sidelobe probability calculation module, used to calculate a first probability that a user terminal falls into the mainlobe area of ​​the aerospace platform, and a second probability that a user terminal falls into the sidelobe area of ​​the aerospace platform; A main-sidelobe system capacity calculation module, used to calculate a first system capacity of the aerospace platform in a mainlobe region, and a second system capacity of the aerospace platform in a sidelobe region; an average system capacity calculation module, used to calculate the average system capacity of each aerospace platform according to the first probability, the second probability, the first system capacity and the second system capacity; The platform selection module is used to select the aerospace platform with the largest average system capacity as the user terminal access platform; The first probability is calculated by the following formula: The second probability is calculated by the following formula: Among them, d j,0 is the distance between the user terminal and the nearest aerospace platform when the user terminal accesses the aerospace fusion network, is the total area of ​​all aerospace platforms in the aerospace integration network. is the visible area of ​​the aerospace platform, P void (·) is the probability that the set is empty, S(x) is the area of ​​the given region, is the main lobe area; The first system capacity is calculated by the following formula: The second system capacity is calculated by the following formula: The average system capacity is calculated by the following formula: Among them, SNR j is the signal-to-interference-and-noise ratio received by the user end, is the main lobe gain of the aerospace platform antenna, is the sidelobe gain of the aerospace platform antenna, is the probability density function of the distance between the user terminal and each aerospace platform when the service aerospace platform is located in the main lobe area, is the probability density function of the distance between the user terminal and each aerospace platform when the service aerospace platform is located in the sidelobe area, X j,0 Y represents the distance between the user terminal and the nearest aerospace platform when the user terminal is located in the main lobe area of ​​the serving aerospace platform when the user terminal accesses the aerospace fusion network. j,0 It represents the distance between the user terminal and the nearest aerospace platform when the user terminal is located in the sidelobe area of ​​the serving aerospace platform when the user terminal accesses the aerospace fusion network, d j,0 is the distance between the user terminal and the nearest aerospace platform when the user terminal accesses the aerospace fusion network, G R is the receiving antenna gain of the user end, p j is the transmission power of the aerospace platform, L AL,j is the constant additional loss caused by environmental factors, λ j is the wavelength, α is the path loss exponent, H j is the flight altitude of the aerospace platform in the aerospace fusion network, The boundary distance between the main lobe and side lobe services in the space-air fusion network, is the visible boundary distance in the air-space fusion network.

8. A mobile communication user terminal, applied to an air-space fusion network to realize communication, wherein the air-space fusion network includes at least one satellite and at least one aircraft, characterized in that: The user end includes a processor and a storage device, wherein the storage device stores a plurality of instructions, and the processor is used to read the plurality of instructions in the storage device and execute the method according to claims 1-6.

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