Inter-satellite link communication method based on constellation networking

Abstract

The application relates to the technical field of inter-satellite link communication, and particularly discloses an inter-satellite link communication method based on constellation networking, which comprises the following steps: step S1: constructing a low-orbit satellite constellation, dividing the low-orbit satellite constellation into a plurality of domains according to geographical regions, selecting a core layer satellite in each domain as a management and control node, and collecting state data of all satellites in the domain; step S2: dividing all current users in the domain into a plurality of service grid points by the core layer satellite, obtaining service demand of each grid point and mapping the service demand into a service demand vector of the domain; meanwhile, mapping current beam coverage of each satellite in the domain into a coverage vector with the same scale as the service grid point; step S3: optimizing and adjusting the beam direction of each satellite based on the service demand vector and the coverage vector of each satellite by the core layer satellite, and generating corresponding beam direction adjustment parameters; and step S4: issuing the adjustment parameters to each satellite in the domain by the core layer satellite, and adjusting the beam direction according to the parameters by each satellite.

Description

Technical Field

[0001] This invention relates to the field of inter-satellite link communication technology, and more specifically to an inter-satellite link communication method based on constellation networking. Background Technology

[0002] Low-Earth orbit (LEO) satellite constellations are the core carriers for building a global satellite internet. Inter-satellite links are key to achieving constellation networking coordination and high-speed data transmission. They can effectively compensate for blind spots in terrestrial communication coverage and support the low-latency and high-reliability communication needs of scenarios such as 6G integrated sensing and computing intelligence, wide-area Internet of Things, and emergency communication.

[0003] Existing inter-satellite link communication lacks a dynamic scheduling mechanism with core-layer satellites as the control center. It cannot collect real-time data on satellite orbits, attitudes, energy consumption, and service load status within the domain. It also lacks algorithm optimization capabilities aimed at minimizing network latency, maximizing resource utilization, and minimizing energy consumption. Furthermore, it cannot dynamically adjust satellite beam direction and operating mode based on user service distribution and channel environment changes. This results in the constellation topology failing to dynamically adapt to service requirements, easily leading to problems such as local network congestion, unbalanced on-board resource allocation, high transmission latency, and wasted satellite energy. Consequently, the transmission efficiency of inter-satellite links and the overall availability of the network cannot be guaranteed, failing to meet the requirements of efficient, stable, and low-power operation of satellite internet. Summary of the Invention

[0004] The purpose of this invention is to provide an inter-satellite link communication method based on constellation networking, and to solve the following technical problems.

[0005] The objective of this invention can be achieved through the following technical solutions: The inter-satellite link communication method based on constellation networking includes the following steps: Step S1: Construct a low-Earth orbit satellite constellation. Divide the low-Earth orbit satellite constellation into several domains according to geographical regions. Select one satellite from all the satellites in each domain as the core layer satellite. The core layer satellite collects the status data of each satellite in its domain. Step S2: The core layer satellite divides all users in the domain at the current time into several service grids, obtains the service demand of each service grid, maps the service demand of each service grid to the service demand vector of the domain, and maps the current beam coverage of each satellite in each domain to a coverage vector of the same scale as the service grid it is located in. Step S3: The core layer satellites adjust the beam direction of each satellite according to the service requirement vector and the coverage vector of each satellite, and generate beam direction adjustment parameters for each satellite. Step S4: The core satellite sends the beam direction adjustment parameters to each satellite, and each satellite adjusts its beam direction according to the beam direction adjustment parameters; after adjustment, the satellites communicate with each other through inter-satellite links.

[0006] As a further aspect of the present invention: the status data includes the satellite's orbital position, attitude, energy consumption, and total energy storage.

[0007] As a further aspect of the present invention: the construction process of the low-Earth orbit satellite constellation includes: The low-Earth orbit satellite constellation is divided into core layer satellites, relay layer satellites, and access layer satellites. The core layer satellites are located in polar orbit and are responsible for inter-satellite data aggregation, routing scheduling, and network management. The relay layer satellites are located in medium and low Earth orbits and are responsible for inter-satellite data forwarding, link relay, and regional coverage coverage. The access layer satellites are located in low Earth orbit and are responsible for user terminal access, data collection, and service transmission.

[0008] As a further aspect of the present invention: the process of dividing all users within the domain at the current moment into several service grid points includes: The geographical area covered by the domain is divided into grids according to a preset spatial resolution to obtain several grid cells. The number of users currently connected in each grid cell is counted and recorded as a statistical value. Grid cells with statistical values ​​greater than a preset threshold are marked as service grids, and the statistical values ​​are used as the service demand of the service grids.

[0009] As a further aspect of the present invention: the mapping process of the business requirement vector includes: The business demand within each business grid is normalized, and a global vector D=[d1, d2, ..., d3] is constructed based on the business demand within each business grid. j ], where d j This represents the business demand of the j-th business grid.

[0010] As a further aspect of the present invention: the mapping process of the coverage vector includes: For the i-th satellite within the domain, obtain the projected coverage area of ​​the i-th satellite's beam on the ground, and obtain the overlap area between the projected coverage area and each service grid point. Calculate the ratio of the overlap area to the area of ​​the projected coverage area, and use this ratio to form the coverage vector C of the i-th satellite. i =[c i，1 c i，2 c i，j] , where c i，j This represents the area ratio between the i-th satellite and the j-th service grid point.

[0011] As a further aspect of the present invention, the process of adjusting the beam direction of each satellite includes: Step S3.1: Obtain the matching degree between the coverage vector of each satellite and the service requirement vector; Step S3.2: Obtain the service centroid of the service demand vector, select the satellite with the highest matching degree with the service demand vector, adjust the beam direction of the satellite so that the coverage vector of the satellite points to the service centroid of the service demand vector, and mark the satellite as the adjusted satellite. Step S3.3: Update the service demand vector in real time, obtain the new service demand vector in real time, and obtain all the remaining satellites except the adjusted satellites. Repeat the above steps for each of the remaining satellites according to the new service demand vector until all satellites in the domain are adjusted satellites, and obtain the beam direction adjustment parameters of each satellite.

[0012] As a further aspect of the present invention: the process of obtaining the matching degree between the satellite's coverage vector and the service demand vector further includes: For the i-th satellite within the domain, obtain the matching degree between the coverage vector of the i-th satellite and the service requirement vector. E i,all E represents the total energy storage of the i-th satellite. i，used This represents the energy consumption of the i-th satellite.

[0013] The beneficial effects of this invention are: 1. This invention achieves spatial morphological matching between beam coverage vector and service requirement vector, and adopts a simple evaluation function that multiplies cosine similarity with energy consumption penalty term. This completely eliminates the iterative convergence process required by traditional metaheuristic methods such as genetic algorithms and particle swarm optimization, reducing the computational complexity of a single topology adjustment from exponential or polynomial level to linear level. The adjustment of hundreds of satellites in a single domain can be completed within milliseconds, meeting the stringent real-time requirements of high-speed motion scenarios of low-orbit satellites. 2. The present invention prioritizes the coverage of the most critical service grid points by first adjusting the satellites, and then the subsequent satellites automatically fill in the remaining uncovered service areas. This fundamentally avoids the waste of resources or beam conflicts caused by multiple satellites competing for the same hot spot. This implicit coordination mechanism does not require any inter-satellite signaling interaction, which significantly reduces system overhead. 3. The energy consumption penalty item of this invention prioritizes satellites with higher remaining energy to undertake heavy service areas, while satellites with lower energy are naturally assigned to light service areas, thus achieving adaptive energy balance across the entire network and extending the overall lifespan of the constellation. 4. This invention achieves near-optimal overall performance in terms of latency, resource utilization, and energy consumption with minimal computational complexity. Attached Figure Description

[0014] The invention will now be further described with reference to the accompanying drawings.

[0015] Figure 1 This is a schematic diagram illustrating the steps of the inter-satellite link communication method based on constellation networking of the present invention; Figure 2 This is a schematic diagram of the low-Earth orbit constellation hierarchical and domain-division networking architecture in the inter-satellite link communication method based on constellation networking of the present invention; Figure 3 This is a schematic diagram of the inter-satellite link structure in the inter-satellite link communication method based on constellation networking of the present invention; Figure 4 This is a flowchart of the low-Earth orbit constellation networking method in the inter-satellite link communication method based on constellation networking of the present invention. Detailed Implementation

[0016] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0017] Please see Figure 1 As shown, this invention is an inter-satellite link communication method based on constellation networking, comprising the following steps: Step S1: Construct a low-Earth orbit satellite constellation. Divide the low-Earth orbit satellite constellation into several domains according to geographical regions. Select one satellite from all the satellites in each domain as the core layer satellite. The core layer satellite collects the status data of each satellite in its domain. In a preferred embodiment of the present invention, the status data includes the satellite's orbital position, attitude, energy consumption, and total energy storage; Specifically, when the core layer satellites collect satellite orbital position and attitude data, they use the Kalman filter algorithm combined with the satellite orbital dynamics model for real-time prediction, with a prediction error of no more than 10m. When the core layer satellite detects a fault in a satellite within its domain or an interruption in the inter-satellite link, it automatically activates the redundant satellite replacement mechanism to reconstruct the local network topology. In a preferred embodiment of the present invention, the process of constructing the low-Earth orbit satellite constellation includes: The low-Earth orbit satellite constellation is divided into core layer satellites, relay layer satellites, and access layer satellites. The core layer satellites are located in polar orbit and are responsible for inter-satellite data aggregation, routing scheduling, and network management. The relay layer satellites are located in medium and low Earth orbits and are responsible for inter-satellite data forwarding, link relay, and regional coverage coverage. The access layer satellites are located in low Earth orbit and are responsible for user terminal access, data collection, and service transmission. Furthermore, the core layer satellites are responsible for global scheduling, while the relay and access layer satellites dynamically adjust their own working status according to the instructions of the core layer, so as to achieve efficient interaction and collaborative transmission of inter-satellite data and improve the overall working efficiency of the constellation. Specifically, the planning process for the low-Earth orbit satellite constellation includes: The orbital parameters, satellite configuration, and network scale of the low-Earth orbit (LEO) constellation are determined. The orbital parameters include orbital altitude, orbital inclination, and orbital period. The orbital altitude is set to 500-1500 km, the orbital inclination to 45°-85° based on global coverage requirements, and the orbital period to 90-120 minutes. The satellite configuration includes the number of satellites per orbital plane and the satellite payloads (communication payloads, navigation payloads, and sensing payloads). The number of satellites per orbital plane is set to 8-12, with each satellite carrying a reconfigurable communication payload supporting multi-band switching. The network scale is set to 8-16 orbital planes based on coverage area requirements to achieve seamless global or regional coverage. Step S2: The core layer satellite divides all users in the domain at the current time into several service grids, obtains the service demand of each service grid, maps the service demand of each service grid to the service demand vector of the domain, and maps the current beam coverage of each satellite in each domain to a coverage vector of the same scale as the service grid it is located in. In a preferred embodiment of the present invention, the process of dividing all users within the domain at the current moment into several service grids includes: The geographical area covered by the domain is divided into grids according to a preset spatial resolution to obtain several grid cells. The number of users currently connected in each grid cell is counted and recorded as a statistical value. Grid cells with statistical values ​​greater than a preset threshold are marked as service grids, and the statistical values ​​are used as the service demand of the service grids. In a preferred embodiment of the present invention, the mapping process of the business requirement vector includes: The business demand within each business grid is normalized, and a global vector D=[d1, d2, ..., d3] is constructed based on the business demand within each business grid. j ], where d j This represents the business demand of the j-th business grid. In a preferred embodiment of the present invention, the mapping process of the coverage vector includes: For the i-th satellite within the domain, obtain the projected coverage area of ​​the i-th satellite's beam on the ground, and obtain the overlap area between the projected coverage area and each service grid point. Calculate the ratio of the overlap area to the area of ​​the projected coverage area, and use this ratio to form the coverage vector C of the i-th satellite. i =[c i，1 c i，2 c i，j ], where c i，j This represents the area ratio between the i-th satellite and the j-th service grid point; Step S3: The core layer satellites adjust the beam direction of each satellite according to the service requirement vector and the coverage vector of each satellite, and generate beam direction adjustment parameters for each satellite. In a preferred embodiment of the present invention, the process of adjusting the beam direction of each satellite includes: Step S3.1: Obtain the matching degree between the coverage vector of each satellite and the service requirement vector; Step S3.2: Obtain the service centroid of the service demand vector, select the satellite with the highest matching degree with the service demand vector, adjust the beam direction of the satellite so that the coverage vector of the satellite points to the service centroid of the service demand vector, and mark the satellite as the adjusted satellite. Step S3.3: Update the service demand vector in real time, obtain the new service demand vector in real time, and obtain all the remaining satellites except the adjusted satellites. Repeat the above steps for each of the remaining satellites according to the new service demand vector until all satellites in the domain are adjusted satellites, and obtain the beam direction adjustment parameters of each satellite. The process of obtaining the matching degree between the satellite coverage vector and the service demand vector also includes: For the i-th satellite within the domain, obtain the matching degree between the coverage vector of the i-th satellite and the service requirement vector. E i,all E represents the total energy storage of the i-th satellite. i，used This represents the energy consumption of the i-th satellite; The process of obtaining the business centroid of the business requirement vector includes: The business centroid of the business demand vector is obtained by using the business demand volume of each business grid point as the weight. Where K is the total number of business grid points, (x j y j () represents the geographic coordinates of the j-th business grid point; It is understandable that the center of mass of services will shift towards areas with dense services. By pointing the satellite beam at this center of mass, the center of beam coverage can be aligned with the center of mass of service distribution, thereby efficiently serving most users. It should be noted that when the service demand vector exhibits a multi-peak distribution, the core layer satellite first performs density-based spatial clustering on the service grid points to divide them into several service clusters. Each service cluster calculates its local service centroid. The satellite preferentially selects the local service centroid closest to itself as the pointing target, and, if the beam width allows, adjusts the beam direction so that the main lobe of the beam covers the local centroid and the main area of ​​its cluster. The multi-peak distribution refers to the spatially geographically separated high-density clustering areas where business demands are distributed. Step S4: The core satellite sends the beam direction adjustment parameters to each satellite, and each satellite adjusts its beam direction according to the beam direction adjustment parameters; after adjustment, the satellites communicate with each other through inter-satellite links; Specifically, the inter-satellite links of this invention include inter-satellite backbone links, inter-satellite relay links, and inter-satellite redundant links. The inter-satellite backbone links are deployed between core-layer satellites and between core-layer and relay-layer satellites, using the laser communication frequency band (1550-1625nm), with a transmission rate of no less than 10Gbps. They employ adaptive modulation and coding technology, dynamically adjusting the modulation method and coding rate according to link quality to improve transmission efficiency. The links adopt a bidirectional transmission design, supporting full-duplex communication to ensure high-speed bidirectional interaction of inter-satellite data. They also incorporate a link encryption module, employing quantum key distribution (QKD) technology to achieve end-to-end security protection for data transmission. The inter-satellite relay links are deployed between relay layer satellites and between relay layer and access layer satellites. They use microwave communication frequency bands (Ka band, 26.5-40GHz) with transmission rates ranging from 110Gbps to 10Gbps. Beamforming technology is used to dynamically adjust the beam direction to achieve precise link connections between satellites. The links employ a dynamic bandwidth allocation mechanism, allocating bandwidth resources according to service priority (urgent services, normal services, and low-priority services) to ensure real-time transmission of urgent services and improve bandwidth utilization. The inter-satellite redundant links are deployed between all adjacent satellites and use a spare frequency band (X band, 8-12GHz) as a backup link for the backbone and relay links. When the main link is interrupted, interfered with, or fails, it automatically switches to the redundant link to achieve link redundancy backup. The redundant links adopt a low-power operating mode and are normally in a dormant state, only starting up when the main link is abnormal, thereby reducing satellite energy consumption. The inter-satellite backbone link adopts a full-duplex communication design and is equipped with a quantum key distribution module to achieve full-process encryption protection for data transmission. Furthermore, the inter-satellite link also includes a link quality monitoring module, which collects parameters such as the link's signal-to-noise ratio, bit error rate, and transmission delay in real time. When the link quality falls below a preset threshold, it automatically triggers link switching or modulation and coding scheme adjustment to ensure link transmission stability; the preset threshold for the bit error rate is no higher than 10. -6 The preset threshold for transmission delay is no more than 50ms; Furthermore, the access layer satellite is equipped with a multi-mode communication module, which supports seamless switching between satellite-to-ground communication and inter-satellite communication. It can achieve efficient data interaction with ground core gateways and user terminals, and at the same time supports the transmission and preprocessing of integrated sensing, computing and intelligence data, adapting to the integrated needs of 6G sensing, computing and intelligence. Furthermore, all satellites in the low-Earth orbit constellation are equipped with energy consumption optimization modules, which reduce satellite energy consumption through intelligent hibernation, power adjustment, and task scheduling optimization. When the satellite energy consumption is lower than a preset threshold, the working mode is automatically adjusted and unnecessary payloads are shut down to ensure that the satellite can work normally in orbit. In addition, when the satellites transmit data through inter-satellite links, an improved A* algorithm is used as an adaptive routing algorithm to calculate the optimal routing path based on real-time topology changes, thus avoiding link congestion and interruption.

[0018] like Figure 2 As shown in the diagram, the low-Earth orbit (LEO) constellation is divided into hierarchical and domain-based networking architectures based on this invention. The LEO constellation is drawn in layers, from top to bottom: core layer, relay layer, and access layer. The core layer is labeled with polar-orbiting satellites (4 satellites, orbital altitude 1200-1500km), the relay layer with medium-low Earth orbit (LEO) satellites (10 satellites per orbital plane, orbital altitude 800-1200km), and the access layer with LEO near-Earth orbit (LEO) satellites (12 satellites per orbital plane, orbital altitude 500-800km). The entire constellation is divided into four geographical domains, each labeled with one core satellite. Satellites within a domain are connected by solid lines, and inter-domain satellites are connected by dashed lines through the core layer satellites. The core functions of each layer are labeled: the core layer is labeled "global scheduling, data aggregation," the relay layer is labeled "link relay, regional blind spot filling," and the access layer is labeled "user access, data collection," clearly defining the hierarchical and domain-based networking structure and the functions of each layer. like Figure 3 As shown in the diagram, based on the inter-satellite link structure of this invention, the inter-satellite links are illustrated using a single core layer satellite, two relay layer satellites, and three access layer satellites as an example. The diagram labels the inter-satellite backbone link, inter-satellite relay link, and inter-satellite redundant link. The inter-satellite backbone link is marked with a thick solid line and labeled "Laser band (1550-1625nm, ≥10Gbps)". The inter-satellite relay link is marked with a thin solid line and labeled "Ka band (26.5-40GHz, 1-10Gbps)". The redundant inter-satellite link is marked with a dashed line and labeled "X band (8-12GHz, spare)". The connection relationships of each link are also indicated: the core layer and the relay layer are the backbone link; the relay layer and the access layer are the relay link; and adjacent satellites are the redundant link. The locations of the link encryption module and the quality monitoring module are also indicated. like Figure 4 As shown in the flowchart of the low-Earth orbit constellation networking method of the present invention, the low-Earth orbit constellation networking method is drawn using a standard flowchart, with arrows connecting each process node in the order of steps. The nodes are clearly labeled, and the specific process nodes are as follows: 1. Constellation parameter planning (marked as "determine orbital parameters, satellite configuration, and network scale"); 2. Construction of a hierarchical and domain-based network architecture (marked as "dividing into core layer, relay layer, and access layer, and dividing into geographical domains"). 3. Dynamic constellation topology adjustment (labeled "orbit prediction, topology optimization, fault compensation"); 4. Inter-satellite collaborative scheduling (labeled "collaborative modeling, task allocation, resource sharing"); 5. Inter-satellite link transmission (marked as "backbone / relay / redundant link collaboration, encrypted data transmission"); 6. Network operation and maintenance management (marked as "status monitoring, fault self-healing, on-orbit upgrade"); 7. Network setup complete (marked "Network is running stably and meets business requirements"); each node is labeled with a serial number, and key nodes are highlighted with a bold border to clearly show the complete execution process of the network setup method.

[0019] The foregoing has provided a detailed description of one embodiment of the present invention, but this description is merely a preferred embodiment and should not be construed as limiting the scope of the invention. All equivalent variations and modifications made within the scope of the present invention should still fall within the scope of the present invention.

Claims

1. An inter-satellite link communication method based on constellation networking, characterized in that, Includes the following steps: Step S1: Construct a low-Earth orbit satellite constellation. Divide the low-Earth orbit satellite constellation into several domains according to geographical regions. Select one satellite from all the satellites in each domain as the core layer satellite. The core layer satellite collects the status data of each satellite in its domain. Step S2: The core layer satellite divides all users in the domain at the current time into several service grids, obtains the service demand of each service grid, maps the service demand of each service grid to the service demand vector of the domain, and maps the current beam coverage of each satellite in each domain to a coverage vector of the same scale as the service grid it is located in. Step S3: The core layer satellites adjust the beam direction of each satellite according to the service requirement vector and the coverage vector of each satellite, and generate beam direction adjustment parameters for each satellite. Step S4: The core satellite sends the beam direction adjustment parameters to each satellite, and each satellite adjusts its beam direction according to the beam direction adjustment parameters; after adjustment, the satellites communicate with each other through inter-satellite links.

2. The inter-satellite link communication method based on constellation networking according to claim 1, characterized in that, In step S1, the status data includes the satellite's orbital position, attitude, energy consumption, and total energy storage.

3. The inter-satellite link communication method based on constellation networking according to claim 1, characterized in that, In step S1, the process of constructing the low-Earth orbit satellite constellation includes: The low-Earth orbit satellite constellation is divided into core layer satellites, relay layer satellites, and access layer satellites. The core layer satellites are located in polar orbit and are responsible for inter-satellite data aggregation, routing scheduling, and network management. The relay layer satellites are located in medium and low Earth orbits and are responsible for inter-satellite data forwarding, link relay, and regional coverage coverage. The access layer satellites are located in low Earth orbit and are responsible for user terminal access, data collection, and service transmission.

4. The inter-satellite link communication method based on constellation networking according to claim 1, characterized in that, In step S2, the process of dividing all users within the domain at the current moment into several service grids includes: The geographical area covered by the domain is divided into grids according to a preset spatial resolution to obtain several grid cells. The number of users currently connected in each grid cell is counted and recorded as a statistical value. Grid cells with statistical values ​​greater than a preset threshold are marked as service grids, and the statistical values ​​are used as the service demand of the service grids.

5. The inter-satellite link communication method based on constellation networking according to claim 1, characterized in that, In step S2, the mapping process of the business demand vector includes: The business demand within each business grid is normalized, and a global vector D=[d1, d2, ..., d3] is constructed based on the business demand within each business grid. j ], where d j This represents the business demand of the j-th business grid.

6. The inter-satellite link communication method based on constellation networking according to claim 4, characterized in that, In step S2, the mapping process of the coverage vector includes: For the i-th satellite within the domain, obtain the projected coverage area of ​​the i-th satellite's beam on the ground, and obtain the overlap area between the projected coverage area and each service grid point. Calculate the ratio of the overlap area to the area of ​​the projected coverage area, and use this ratio to form the coverage vector C of the i-th satellite. i =[c i，1 c i，2 c i，j ], where c i，j This represents the area ratio between the i-th satellite and the j-th service grid point.

7. The inter-satellite link communication method based on constellation networking according to claim 1, characterized in that, In step S3, the process of adjusting the beam direction of each satellite includes: Step S3.1: Obtain the matching degree between the coverage vector of each satellite and the service requirement vector; Step S3.2: Obtain the service centroid of the service demand vector, select the satellite with the highest matching degree with the service demand vector, adjust the beam direction of the satellite so that the coverage vector of the satellite points to the service centroid of the service demand vector, and mark the satellite as the adjusted satellite. Step S3.3: Update the service demand vector in real time, obtain the new service demand vector in real time, and obtain all the remaining satellites except the adjusted satellites. Repeat the above steps for each of the remaining satellites according to the new service demand vector until all satellites in the domain are adjusted satellites, and obtain the beam direction adjustment parameters of each satellite.

8. The inter-satellite link communication method based on constellation networking according to claim 7, characterized in that, In step S3, the process of obtaining the matching degree between the satellite's coverage vector and the service demand vector further includes: For the i-th satellite within the domain, obtain the matching degree between the coverage vector of the i-th satellite and the service requirement vector. E i,all E represents the total energy storage of the i-th satellite. i，used This represents the energy consumption of the i-th satellite.

9. The inter-satellite link communication method based on constellation networking according to claim 7, characterized in that, In step S3, the process of obtaining the business centroid of the business demand vector includes: The business centroid of the business demand vector is obtained by using the business demand volume of each business grid point as the weight. Where K is the total number of business grid points, (x j y j ) represents the geographic coordinates of the j-th business grid point.

Images