A method for suppressing spatiotemporal ripple effects in a sky-ground integrated network

Abstract

The present invention discloses a method for suppressing the space-time ripple effect of a sky-ground integrated network, comprising the following steps: S1. Given a communication satellite, M A drone, N The paper proposes an integrated sky-ground network with 30 ground base stations: S2. Access points at each layer communicate using a shared spectrum and a unified frame structure, partitioning the spectrum and assigning constraints to channel allocation. S3. The spatiotemporal ripple effect is modeled by combining spatial and temporal interference to characterize and suppress the spatiotemporal ripple effect. This paper analyzes the spatiotemporal interference in the integrated sky-ground network, models it, and defines it as a ripple effect, characterizing the interference relationships and suppression conditions between different access points.

Description

Technical Field

[0001] The present invention relates to the field of communications, and in particular to a method for suppressing space-time ripple effects in a sky-ground integrated network. Background Art

[0002] The rapid development of communications technology has posed numerous challenges to traditional networks in meeting the requirements for low latency, high reliability, and ultra-large-scale connectivity. Against this backdrop, the concept of a Space-Air-Ground Uniformly Integrated Network (SAGUIN) has been proposed, based on the concept of a space-ground integrated network. This network integrates satellite, aerial, and terrestrial networks to provide users with wide-coverage, highly dynamic, and high-throughput communication services. However, in this architecture, the overlapping coverage areas of multiple layers of access points (APs) and the varying propagation delays between APs at different layers lead to complex spatiotemporal interference during communications. Modeling and quantifying the spatiotemporal interference between different APs in the network remains an unresolved research challenge, leaving a gap in this area of ​​research. Summary of the Invention

[0003] The purpose of the present invention is to overcome the shortcomings of the existing technology and provide a method for suppressing the spatiotemporal ripple effect of an integrated sky-ground network. The spatiotemporal interference in the integrated sky-ground network is analyzed, modeled and defined as a ripple effect, and the interference relationship and suppression conditions between different access points are characterized.

[0004] The object of the present invention is achieved through the following technical solution: a method for suppressing the spatiotemporal ripple effect of a sky-ground integrated network, comprising the following steps:

[0005] S1. Given a communication satellite, M A drone, N An integrated sky-ground network with 10 ground base stations:

[0006] The communication satellites constitute a satellite network, i.e., the satellite layer, for providing coverage for wide-area users; the M drones constitute an aerial network, i.e., the aerial layer, for dynamically covering designated hotspot areas; the N ground base stations constitute a ground network, i.e., the ground layer, for providing high-data-rate access to users; access points are provided in the satellite layer, the aerial layer, and the ground layer; the access points communicate with each other via intra-layer links and cross-layer links;

[0007] S2. Access points at each layer communicate using a shared spectrum with a unified frame structure, which divides the spectrum and imposes constraints on channel allocation: no single resource block can be allocated to multiple users simultaneously.

[0008] S3. Combine spatial and temporal interference to model the spatiotemporal ripple effect and obtain the characterization and suppression conditions of the spatiotemporal ripple effect.

[0009] The beneficial effects of the present invention are: the present invention analyzes the spatiotemporal interference existing in the integrated sky-ground network, models and defines it as a ripple effect, characterizes the interference relationship between different access points, provides conditions for coordinating and preventing mutual interference between access points, and provides a new theoretical basis and technical method for this research field. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] Figure 1 is a flow chart of the method of the present invention;

[0011] Figure 2 This is a schematic diagram of the sky-ground integrated network;

[0012] Figure 3 Schematic diagram of the frame structure of the sky-ground integrated network;

[0013] Figure 4 Modeling scene graphs for spatiotemporal ripple effects. DETAILED DESCRIPTION

[0014] The technical solution of the present invention will be further described in detail below with reference to the accompanying drawings, but the protection scope of the present invention is not limited to the following.

[0015] like Figure 1 As shown, a method for suppressing the spatiotemporal ripple effect of a sky-ground integrated network includes the following steps:

[0016] S1. Given a space-ground integrated network architecture consisting of satellite network, air network, and ground network:

[0017] like Figure 2 As shown in the figure, the Space-Air-Ground Uniformly Integrated Network (SAGUIN) consists of a satellite network, an aerial network, and a ground network. The satellite network includes one or more communication satellites, providing coverage for users over a wide area. The aerial network includes unmanned aerial vehicles (UAVs) and high-altitude platforms (HAPs), which dynamically cover specific hotspots. The base stations in the ground network provide users with high-data-rate access. Access points can communicate with each other via intra-layer and cross-layer links. In this architecture, users connect to the network through access points to obtain services, and data is transmitted through the corresponding network to the Data and Control Center (DCC) for processing, thus achieving unified coordination and management of resources.

[0018] To simplify the scene structure, such as Figure 4 As shown, consider a communication satellite, M A drone, N An integrated sky-ground network with 10 ground base stations:

[0019] The communication satellites constitute a satellite network, i.e., the satellite layer, for providing coverage for wide-area users; the M drones constitute an aerial network, i.e., the aerial layer, for dynamically covering designated hotspot areas; the N ground base stations constitute a ground network, i.e., the ground layer, for providing high-data-rate access to users; access points are provided in the satellite layer, the aerial layer, and the ground layer; the access points communicate with each other via intra-layer links and cross-layer links;

[0020] S2. Access points at each layer communicate using a shared spectrum, adopting a unified frame structure, partitioning the spectrum, and specifying the constraints that must be met for channel allocation.

[0021] like Figure 3 As shown in Figure 1, access points (APs) at each layer use shared spectrum for communication and adopt a unified frame structure. In each frame, frequency division multiple access technology is used to divide the spectrum into P Resource Block (RB). Access Point k At the moment t The action set is defined as ,in: U Indicates the total number of users, P Indicates the total number of channels; Indicates latitude U*P 0-1 matrix of; express The first ( u,p ) elements. Specifically, Indicates time t , access point k Resource Block p Assigned to user u ;and This means that the channel is not allocated. t , any one resource block will not be allocated to multiple users at the same time, and the allocation of each channel must meet the following constraints:

[0022]

[0023] in, K Indicates the total number of access points, P Indicates the total number of available channels. U Indicates the total number of users.

[0024] S3. Combine spatial and temporal interference to model the spatiotemporal ripple effect and obtain a representation of the spatiotemporal ripple effect.

[0025] The ripple effect is a complex spatiotemporal interference phenomenon caused by overlapping coverage and propagation delay of multiple access points. To accurately describe the ripple effect, consider Figure 4 The scene contains a communication satellite. M A drone, N For the sake of index clarity, the communication satellite index is defined as k = 0, the drone index is: , the base station index is: The following modeling method is proposed:

[0026] To characterize the spatial and temporal interference in the network, the following definitions are made:

[0027] make Indicates access point k The ground level communication radius of the access point k and users u The coordinates of and If the distance between them is less than or equal to , then the user u Considered to be at the access point k Within the coverage area, and ,in, Is the coverage indicator parameter; otherwise, the user is not within the coverage area and Access Point k and users u The coverage relationship between them is expressed as:

[0028]

[0029] Access Point k and users u The propagation delay between It is determined by the physical distance between the two and the type of access point. It can be calculated as:

[0030]

[0031] in, represents the two-norm of the variable, c Represents the speed of light. When the access point is a ground base station, the propagation delay is 0.

[0032] Spatial interference is defined as: when the users covered by different access points overlap in spatial areas, downlink transmission will cause related interference between the access points and users at the corresponding spatial locations. The spatial interference formula is expressed as:

[0033]

[0034] in, is with k Compared to lower-level access nodes; Indicates access point exist Time slot actions; Indicates access point With users u propagation delay; U , P , K Represent the total number of users, total number of channels and total number of access points respectively.

[0035] Time interference is defined as the inconsistency of propagation delays at each access point. Data packets transmitted from different access points at different times may arrive at the user end at the same time after experiencing different propagation delays, thus causing interference. The time interference formula is expressed as:

[0036]

[0037] in, Indicates access node k exist Transmission action of time slot; summation term Indicates all covered users u The total transmission result of the access points is . This formula shows that in any time slot, the user receives service data from at most one access point.

[0038] Based on the above analysis, the interference of the integrated sky-ground network originates from the transmitter, propagates through each layer, and gradually dissipates over time, similar to the ripple effect caused by an object dropping into the water surface. Combining the interference in space and time, it is defined as the space-time ripple effect, and the final expression of the space-time ripple effect is given:

[0039]

[0040] The suppression conditions of space-time ripple effects are given as follows:

[0041]

[0042] Item 1 , check the access point k Whether to choose Select service; item 2 Evaluate the number of access points from all other access points in the resource block p This equation ensures proper coordination and prevents mutual interference between access points, given the transmission conditions on the access points.

[0043] Since there are multiple access points in the network, it is necessary to determine whether there is mutual interference between the access points. In formula (7), the first term Indicates whether access point k is Use channel p to transmit data to user u at time: 0 means no, 1 means yes; the second item Indicates that all access points except access point k cover user u (i.e. ) whether the access point k' is in the corresponding Channel p is used at all times to serve user u (here it refers to the same user u): 0 means no, non-zero means yes. The services in these two items undergo their own propagation delay ( ) will reach user u at time t. Since statistics are required for all access points other than access point k, the second term is summed (since it is a summation term, its value can be 1, 2, 3, etc.). When neither of these two conditions occurs, or only one of them occurs (when the second term occurs, its value must be 1, otherwise mutual interference will occur), no interference will occur at the user end (neither condition occurs, indicating that the user end has not received service; only one condition occurs, indicating that the user is successfully served), and the expression evaluates to 0 or 1. If both conditions occur simultaneously, then at time t, the user will receive service from multiple APs on channel p, resulting in co-channel interference (the expression evaluates to greater than 1), preventing successful service. Therefore, the condition here must use an inequality and require that the overall expression evaluate to less than or equal to 1, limiting the user to receiving service from at most one access point at time t, thereby avoiding mutual interference.

[0044] The foregoing description is a preferred embodiment of the present invention. It should be understood that the present invention is not limited to the form disclosed herein and should not be construed as excluding other embodiments. Instead, the present invention can be used in other combinations, modifications, and environments and can be modified within the scope of the concept described herein through the above teachings or techniques or knowledge in the relevant field. Modifications and variations made by those skilled in the art that do not depart from the spirit and scope of the present invention are intended to be protected by the appended claims.

Claims

1. A method for suppressing spatiotemporal ripple effects in a sky-ground integrated network, characterized by: The following steps are involved: S1. Given a communication satellite, M A drone, N An integrated sky-ground network with 10 ground base stations: The communication satellites constitute a satellite network, i.e., the satellite layer, for providing coverage for wide-area users; the M drones constitute an aerial network, i.e., the aerial layer, for dynamically covering designated hotspot areas; the N ground base stations constitute a ground network, i.e., the ground layer, for providing high-data-rate access to users; the communication satellites, drones, or ground base stations serve as access points; and the access points communicate with each other via intra-layer links and cross-layer links. S2. Access points at each layer communicate using a shared spectrum with a unified frame structure, which divides the spectrum and imposes constraints on channel allocation: no single resource block can be allocated to multiple users simultaneously. S3. Model the spatiotemporal ripple effect by combining spatial and temporal interference to obtain the characterization and suppression conditions of the spatiotemporal ripple effect; The step S3 comprises: S301. Define the spatiotemporal ripple effect as a complex spatiotemporal interference phenomenon caused by overlapping coverage and propagation delays of multiple access points, and give the indices of satellites, drones, and ground base stations; S302 defines time interference and space interference; S303. Modeling the spatiotemporal ripple effect by combining spatial and temporal interference to obtain the characterization and suppression conditions of the spatiotemporal ripple effect; The step S303 includes: Interference in the integrated sky-ground network originates from the transmitter, propagates through each layer, and gradually dissipates over time, similar to the ripple effect caused by an object dropping into the water surface. Combining the interference in space and time, it is defined as the space-time ripple effect, and the final expression of the space-time ripple effect is given: in, express The first ( u,p ) elements, Indicates access point k At the moment t The action set, U Indicates the total number of users, P Indicates the total number of available channels. Indicates the dimension U*P 0-1 matrix of; For access points k and users u The propagation delay between Indicates access point k and users u the coverage relationship between them; is with k Compared to lower-level access nodes; K Indicates the total number of access points; The suppression conditions of space-time ripple effects are given as follows: Item 1 , check the access point k Whether to choose Select service; item 2 Evaluate the number of access points from all other access points in the resource block p transmission conditions on the network, ensuring proper coordination and preventing interference between access points.

2. The method for suppressing spatiotemporal ripple effects in a sky-ground integrated network according to claim 1, characterized in that: In step S2, the frequency division multiple access technology is used in each frame to divide the spectrum into P resource blocks, each resource block is a channel, access point k At the moment t The action set is defined as ,in: U Indicates the total number of users, Indicates the dimension U*P 0-1 matrix of; express The first ( u,p ) elements; Indicates time t , access point k Resource Block p Assigned to user u ;and It means that the channel has not been allocated; To ensure that at any time t , any one resource block will not be allocated to multiple users at the same time, and the allocation of each channel must meet the following constraints: in, K = Indicates the total number of access points, P Indicates the total number of available channels. U Indicates the total number of users.

3. The method for suppressing spatiotemporal ripple effects in a sky-ground integrated network according to claim 1, characterized in that: The step of communication satellite index is defined as k = 0, the drone index is: , the ground base station index is: .

4. The method for suppressing spatiotemporal ripple effects in a sky-ground integrated network according to claim 1, characterized in that: The step S302 includes: To characterize the spatial and temporal interference in the network, the following definitions are made: make Indicates access point k The ground level communication radius of the access point k and users u The coordinates of and ; If the distance between them is less than or equal to , then the user u Considered to be at the access point k Within the coverage area, and ,in, Is the coverage indicator parameter; otherwise, the user is not within the coverage area and ; Access Point k and users u The coverage relationship between them is expressed as: Access Point k and users u The propagation delay between It is determined by the physical distance between the two and the type of access point, and can be calculated as: in, represents the two-norm of the variable, c Represents the speed of light. When the access point is a ground base station, the propagation delay is 0. Definition of spatial interference: When the users covered by different access points overlap in spatial areas, downlink transmission will cause correlated interference between the access points and users at the corresponding spatial locations. The spatial interference formula is expressed as: in, is with k Compared to lower-level access nodes; Indicates access point exist Time slot actions; Indicates access point With users u propagation delay; U , P , K Represents the total number of users, total number of channels and total number of access points respectively; Definition of time interference: The propagation delays of different access points are inconsistent. Data packets transmitted by different access points at different times may arrive at the user end at the same time after experiencing different propagation delays, thus causing interference. The time interference formula is expressed as: in, Indicates access node k exist Transmission action of time slot; summation term Indicates all covered users u The total transmission result of the access point is , and the formula shows that in any time slot, the user receives service data from at most one access point.

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