Low-altitude unmanned aerial vehicle group dual-frequency link emergency networking method and system thereof

Abstract

The application discloses a kind of low-altitude unmanned aerial vehicle group dual-frequency link emergency networking method and system thereof, method includes: the low-frequency control link of low-altitude unmanned aerial vehicle is built, wherein the low-frequency control link adopts full-distributed control link networking mode;Second, the network control data is shared by the low-frequency control link, and the global information of control link is obtained, wherein the global information includes unmanned aerial vehicle positioning information, physical environment and communication resources;Then, according to the global information, high-frequency data link is constructed, and data transmission is carried out through the high-frequency data link;Finally, based on the low-frequency control link and high-frequency data link, dual-frequency link emergency networking is built by high-low frequency combination mode.The application can form more stable and more reliable control network, provide more timely control information support for the construction of high-frequency data link, better solve the problem of data retransmission under high dynamic topology of unmanned aerial vehicle.

Description

A method and system for emergency networking of dual-frequency links for low-altitude unmanned aerial vehicle (UAV) swarms Technical Field

[0001] This invention belongs to the field of low-altitude unmanned aerial vehicle (UAV) swarm data transmission technology, and particularly relates to a dual-frequency link emergency networking method and system for low-altitude UAV swarms. Background Technology

[0002] In the field of urban emergency rescue, drones, as an emerging low-altitude aircraft, have been widely recognized and applied to various emergency situations, including natural disaster response, disaster relief, and social security management. These aircraft, leveraging their all-area deployment capabilities, all-terrain mobility, and comprehensive three-dimensional coverage, provide crucial support for rescue operations. Drones have demonstrated unique advantages, particularly in aerial fire monitoring and surveillance of large public areas. They can be equipped with high-definition cameras and other multi-mode sensors to build a self-organizing network, enabling rapid collection and transmission of rescue information. This significantly expands the aerial dimension of urban emergency rescue and effectively improves rescue efficiency. These modular and programmable aircraft have become an indispensable part of low-altitude rescue operations.

[0003] While drones play a vital role in urban emergency rescue, existing technologies still face a series of challenges in practical applications. First, the high mobility of drones and the complex communication environments of emergency scenarios lead to frequent changes in network topology, making traditional single-band links prone to disconnection and causing frequent data retransmissions, severely impacting the connectivity and stability of aerial networks. Second, drone flight control and network control information are mixed with emergency situational data transmitted on the same link, increasing the complexity of the time-division multiplexing allocation mechanism and incurring additional signaling overhead. Furthermore, the different transmission requirements of different data types share spectrum resources on the same link, resulting in wasted spectrum resources. More seriously, link disconnections prevent timely exchange of control data and hinder the effective control of the time-varying characteristics of the network topology, reducing rescue efficiency and increasing the risk of drone damage. Summary of the Invention

[0004] To address the aforementioned technical challenges, and considering the diverse needs of multi-source heterogeneous data communication and the high dynamism of UAV network topologies, this invention designs a UAV communication network topology based on a dual-link architecture. It employs a combination of high and low frequencies to transmit control information and data information separately. By establishing an efficient and stable two-layer transmission network, it ensures the interaction of basic control information of the UAV and solves the problem of stable flow of multimedia data such as audio and video under highly dynamic topologies.

[0005] To achieve the above objectives, in a first aspect, the present invention provides a method for emergency networking of low-altitude unmanned aerial vehicle (UAV) swarms using dual-frequency links, comprising:

[0006] Construct a low-frequency control link for low-altitude unmanned aerial vehicles (UAVs), wherein the low-frequency control link adopts a fully distributed control link networking method;

[0007] By sharing network control data through the low-frequency control link, global information of the control link is obtained, wherein the global information includes UAV positioning information, physical environment and communication resources;

[0008] Based on the global information, a high-frequency data link is constructed, and data is transmitted through the high-frequency data link.

[0009] Based on the low-frequency control link and high-frequency data link, a dual-frequency link emergency network is built by combining high and low frequencies.

[0010] Preferably, constructing a low-frequency control link for a low-altitude unmanned aerial vehicle (UAV) includes:

[0011] The system acquires the self-information broadcast by each drone at maximum power, interacts with the self-information and signaling information to acquire information about surrounding drones; wherein, the signaling information is control information exchanged between drones.

[0012] Based on information about surrounding drones, links between drones are paired and low-frequency control links for low-altitude drones are established.

[0013] Preferably, the low-frequency control link uses a networking module that supports the Wifi Halow protocol, and the frequency band is selected as 840MHz.

[0014] Preferably, constructing a high-frequency data link includes:

[0015] Based on the global information, an initial high-frequency data link is established;

[0016] The differences between the network formed by the UAV communicating at maximum power and the initial high-frequency data link are evaluated to obtain a set of optional links;

[0017] In each round, a link that provides the greatest utility is found from the set of available links, wherein the link belongs to the set of available links;

[0018] Remove the link from the set of available links until the set of available links is empty.

[0019] Preferably, the construction method also includes an urban low-altitude channel model based on probabilistic line-of-sight wireless transmission, which comprehensively considers the impact of building obstruction on signal propagation between UAVs and derives the average path loss for direct communication between UAVs.

[0020] Preferably, the construction method also includes the process of optimizing the dual-frequency link emergency networking:

[0021] Select different transmission carrier frequencies according to the different types of information transmission requirements of the drone;

[0022] The transmission power is adjusted based on the actual environment of each drone and the distance between nodes.

[0023] Secondly, the present invention also provides a dual-frequency link emergency networking system for low-altitude unmanned aerial vehicle (UAV) swarms, comprising:

[0024] The first link construction module is used to construct the low-frequency control link of the low-altitude UAV, wherein the low-frequency control link adopts a fully distributed control link networking mode.

[0025] The information acquisition module is used to obtain global information of the control link by sharing network control data through the low-frequency control link, wherein the global information includes UAV positioning information, physical environment and communication resources;

[0026] The second link construction module is used to construct a high-frequency data link based on the global information and to transmit data through the high-frequency data link;

[0027] The dual-frequency link emergency networking module is used to build a dual-frequency link emergency network based on the low-frequency control link and the high-frequency data link, using a combination of high and low frequencies.

[0028] Thirdly, the present invention also discloses a computer device, including a memory, a processor, and a computer program stored in the memory, wherein the processor executes the computer program to implement the steps of the method described in the first aspect.

[0029] Fourthly, the present invention also discloses a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the steps of the method described in the first aspect.

[0030] Fifthly, the present invention also discloses a computer program product, including a computer program that, when executed by a processor, implements the steps of the method described in the first aspect.

[0031] Compared with the prior art, the present invention has the following advantages and technical effects:

[0032] This invention provides a dual-frequency link emergency networking method for low-altitude unmanned aerial vehicle (UAV) swarms. First, a low-frequency control link for the low-altitude UAVs is constructed, wherein the low-frequency control link adopts a fully distributed control link networking mode. Second, global information of the control link is obtained by sharing network control data through the low-frequency control link, wherein the global information includes UAV positioning information, physical environment, and communication resources. Next, a high-frequency data link is constructed based on the global information, and data transmission is performed through the high-frequency data link. Finally, based on the low-frequency control link and the high-frequency data link, a dual-frequency link emergency network is built using a combination of high and low frequencies.

[0033] This invention designs a dual-link emergency networking architecture that separates the low-frequency control link and the high-frequency data link. By prioritizing the construction of the low-frequency control link for low-altitude UAVs, it establishes a long-distance network link while meeting the high signal penetration requirements of emergency low-altitude scenarios, forming a more stable and reliable control network. This enables larger-scale network control data sharing and provides a more efficient networking solution for the construction of the high-frequency data link. Under the condition of global information interconnection, this invention constructs a stable data transmission link based on the information of the control link and the physical location and spectrum bandwidth resources of different UAVs, ensuring the requirements of high-speed and high-real-time data transmission such as video, and better solving the problem of data retransmission under the highly dynamic topology of UAVs. Attached Figure Description

[0034] The accompanying drawings, which form part of this application, are used to provide a further understanding of this application. The illustrative embodiments and descriptions of this application are used to explain this application and do not constitute an undue limitation of this application. In the drawings:

[0035] Figure 1 is a scenario diagram of a drone self-organizing network based on dual links according to an embodiment of the present invention;

[0036] Figure 2 is a schematic diagram of a low-frequency control link network according to an embodiment of the present invention;

[0037] Figure 3 is a schematic diagram of the initial high-frequency data link network according to an embodiment of the present invention;

[0038] Figure 4 is a schematic diagram of the optimized high-frequency data link network according to an embodiment of the present invention;

[0039] Figure 5 is a schematic diagram of the average link latency change during the link construction process according to an embodiment of the present invention. Detailed Implementation

[0040] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other. This application will now be described in detail with reference to the accompanying drawings and embodiments.

[0041] It should be noted that the steps shown in the flowchart in the accompanying drawings can be executed in a computer system such as a set of computer-executable instructions, and although a logical order is shown in the flowchart, in some cases the steps shown or described may be executed in a different order than that shown here.

[0042] The technical terms used in the following embodiments will be explained first.

[0043] (1) The control link refers to the signal transmission link used to control the flight of the UAV. Generally, the frequency band for transmitting control information is 840.5MHz-845MHz, while data information (including images, videos, etc.) is generally transmitted using the 2.4GHz / 5GHz frequency band with a larger bandwidth. The control link is the most basic link of the UAV. Flight control signals and remote control signals are transmitted through this link. The joystick of the remote controller can control the UAV to fly up and down, turn left and right, pitch and other actions.

[0044] How the control link works: The main function of the control link is to transmit flight control signals and remote control signals via radio frequency signals, enabling the drone to respond to the remote controller's operations. Specifically, the control link transmits remote controller commands to the drone via 840.5MHz-845MHz radio frequency signals, and the drone executes the corresponding actions based on the received commands.

[0045] Application scenarios of control links: Control links are primarily used for the flight control of drones, ensuring that the drone operates according to the operator's instructions. Because the communication radius of the control link is relatively short (generally within a few kilometers), it is necessary to operate the drone within a certain range to ensure stable signal transmission and safe flight.

[0046] (2) Dual-band link refers to a device having two independent communication radio frequency circuits, both of which can realize communication and networking. These two circuits use different frequency bands, one high (2.4GHz) and the other low (840MHz), to form two communication networks with different frequency bands. In this embodiment, the two frequency bands are used simultaneously to transmit different information (low frequency transmits control information, and high frequency transmits data information).

[0047] Dual-band links operate based on routers or wireless devices simultaneously using both the 2.4GHz and 840MHz frequency bands. Each of these bands has its own advantages and disadvantages:

[0048] 840MHz band: wide coverage, but susceptible to interference from other wireless devices.

[0049] 2.4GHz band: Fast transmission speed and strong anti-interference ability, but smaller coverage area.

[0050] Dual-band link application scenarios: In practical use, dual-band links can automatically switch frequency bands based on factors such as device distance and internet access needs to provide the best wireless experience. For example, when a device is far from the router, it may automatically switch to the 2.4GHz band to ensure signal strength; while when high-speed transmission is required, it will switch to the 5GHz band.

[0051] The difference between dual-band links and other technologies: Compared to single-band links, dual-band links offer greater flexibility and a better user experience. Single-band links can only use one frequency band, while dual-band links have two independent links operating simultaneously, providing better network performance and stability.

[0052] (3) Line of sight (LOS) wireless transmission refers to the transmission of signals when the transmitting antenna and the receiving antenna can "see" each other. This transmission method requires that there are no obstacles between the transmitting antenna and the receiving antenna, or that the influence of obstacles on the signal can be ignored.

[0053] Line-of-sight wireless transmission can be mainly divided into the following categories:

[0054] Complete line-of-sight (LOS) transmission: There are no obstacles between the transmitting and receiving antennas that affect signal propagation, allowing the signal to be transmitted completely.

[0055] Near-line-of-sight (nLOS) transmission: There are some obstacles between the transmitting and receiving antennas, but these obstacles have little impact on the signal, and the signal can be partially transmitted.

[0056] Non-line-of-sight (NLOS) transmission: The transmitting and receiving antennas are completely blocked by an obstacle, and the signal cannot be transmitted directly.

[0057] Applications of line-of-sight (LAS) wireless transmission: LAS is widely used in various communication systems, especially when setting up WiFi networks. It's necessary to determine the type of LAS based on the specific circumstances and select the appropriate wireless installation system. Furthermore, LAS also has important applications in radio wave propagation, particularly in the VHF and UHF bands. These signals propagate primarily in a straight line, typically over distances ranging from tens to hundreds of kilometers.

[0058] Advantages of line-of-sight wireless transmission:

[0059] Stable signal: Due to the absence of obstacles, the signal propagates stably with minimal attenuation.

[0060] High transmission speed: Because it propagates in a straight line, the signal travels at a high speed.

[0061] Example 1

[0062] This embodiment provides a method for emergency networking of low-altitude unmanned aerial vehicle (UAV) swarms using dual-frequency links, including:

[0063] Construct a low-frequency control link for low-altitude unmanned aerial vehicles (UAVs), wherein the low-frequency control link adopts a fully distributed control link networking method;

[0064] By sharing network control data through the low-frequency control link, global information of the control link is obtained, wherein the global information includes UAV positioning information, physical environment and communication resources;

[0065] Based on the global information, a high-frequency data link is constructed, and data is transmitted through the high-frequency data link.

[0066] Based on the low-frequency control link and high-frequency data link, a dual-frequency link emergency network is built by combining high and low frequencies.

[0067] Specifically, this embodiment provides an architecture example that separates control information from data information. The low-frequency control link network uses a networking module supporting the Wi-Fi Halow protocol, with the frequency band selected at 840MHz. This protocol, with its features of large connectivity (supporting up to 8191 nodes), long distance (maximum 1km coverage for a single AP, supporting Relay APs), high reliability, low power consumption, and good security (supporting the 802.11 encryption standard), perfectly meets the requirements for control data transmission and efficiently enables rapid interaction of lower-level control data. The high-frequency data link networking equipment uses a self-organizing network radio from the UAV, with the frequency band selected at 2.4GHz. Using global information such as UAV positioning, physical environment, and communication resources obtained through the control link, a stable high-frequency data link is constructed by adjusting its own transmission power, efficiently realizing the flow of collected data between UAVs and avoiding redundant data collection.

[0068] As an additional implementation method, a multi-UAV network topology model based on a dual-link architecture is shown in Figure 1. The UAV set is defined as... V represents the total number of drones. The low-frequency control link is the control information transmission layer, used to transmit short-packet, high-real-time information such as drone location information, signal perception information, and movement trajectory information; the high-frequency data link is the data transmission layer, used to transmit long-packet, high-throughput data information such as audio and video collected by the drones.

[0069] 1. Channel model;

[0070] This embodiment employs a probabilistic line-of-sight (LoS) wireless transmission model for urban low-altitude channels, comprehensively considering the impact of building obstruction on signal propagation between drones, and derives the average path loss for direct communication between drones. The scenario is assumed to be a system consisting of T extremely short timestamps, where... Therefore, for each timestamp t, the drone is static. Let the drone's coordinates at time t be... The distance between drone a and drone b is Therefore, the channel gain between drone a and drone b can be expressed as:

[0071] (1)

[0072] Where β represents the large-scale fading factor; h is the small-scale fading factor, and its expected value is 1, i.e. .

[0073] In reality, drones may lack any additional information regarding altitude, exact location, number of obstacles, and channel conditions. Therefore, when designing drone-based communication systems, the randomness inherent in line-of-sight (LOS) and non-line-of-sight (LOS) links must be considered. For air-to-air communication, the line-of-sight Loss (LOS) probability between drone a and drone b is modeled based on the environment, the drones' positions, and elevation angles:

[0074] (2)

[0075] Here, C and D represent propagation parameters and constant values, which depend on the carrier frequency and environment type, such as rural, urban, or densely built-up urban areas. This represents the elevation angle. According to formula (2), the larger the elevation angle, the greater the probability of Loss of Sense (LoS). Furthermore, the channel gain of the UAV equipment is introduced:

[0076] (3)

[0077] Where fc is the carrier frequency, α is the path loss exponent, η1 and η2 (η2>η1>1) are the additional path loss coefficients for LoS and NLoS respectively, and c is the speed of light. Furthermore, the channel gain determined by LoS and NLoS can be corrected as follows:

[0078] (4)

[0079] Wherein, the regularized LoS probability is . Let represent the channel gain when the distance is 1. Therefore, the signal power received by UAV a from UAV b can be expressed as: Where pr is the received power and pt is the transmitted power.

[0080] Meanwhile, the transmission rate between drones can be expressed as:

[0081] (5)

[0082] 2. High-frequency data link model;

[0083] In drone swarm operations, the drone communication system can be viewed as a relay network, where remote data transmission and interaction require forwarding through other drones. The essence of drone ad hoc network link design is to ensure that at least one reachable path exists between any two drones in the entire network, achieving full network connectivity. Furthermore, a crucial indicator for evaluating the efficient collaborative work of a drone swarm is the network's average path delay, which reflects the frequency of data exchange and is expressed as:

[0084] (6)

[0085] in, Let L be the transmission delay from drone a to drone b. Assume the length of the transmitted data packet is L(a,b), the shortest path from a to b is H(a,b), and R is the transmission rate from i to j. It can be represented as:

[0086] (7)

[0087] Furthermore, the limited spectrum resources available for building high-frequency data networks using drone self-organizing radios result in an upper limit on the number of high-frequency data links in the system. This embodiment defines the overhead of building a direct link from drone a to drone b as:

[0088] (8)

[0089] Where c is the link cost per unit distance.

[0090] 3. A dual-link-based UAV networking method

[0091] 3.1 Low-frequency control link networking method;

[0092] Traditional drone networking methods employ global traversal combined with centralized control, suitable for scenarios where nodes are close together and few in number, and communication channels are pre-allocated. However, urban low-altitude drone swarms, due to the greater distance between drones and the lack of a ground control center, often suffer from insufficient power output from individual drones to achieve full network coverage, thus preventing centralized unified networking.

[0093] Considering the above scenario, as an additional implementation method, this embodiment proposes a fully distributed control link networking approach: all UAVs first broadcast their own information at maximum power to achieve signaling and information interaction within a certain range; then, based on the information received from other UAVs, they achieve link pairing between UAVs and complete the construction of the overall network. As shown in Figure 2, the specific networking method is as follows:

[0094] Equipment requirements: Each drone is equipped with a Wifi HaLow protocol communication module that supports networking.

[0095] Step 1: Plan the network topology: Determine the location, number, and connection methods between the nodes of the ad hoc network;

[0096] (1) Broadcast its own information (SSID, etc.) at maximum power;

[0097] (2) Receive broadcast information from surrounding drones and build a preferred neighbor list based on the received signal strength;

[0098] (3) Broadcast its own link to build a preference list;

[0099] Based on the received list of preferences of surrounding drones, a link construction matching request is issued;

[0100] (4) Upon receiving a link construction request, complete the matching and adjust its own transmission power (this power level only needs to meet the power required for the connection of the farthest node) to realize the construction of its respective network topology.

[0101] Step 2: Configure self-organizing nodes;

[0102] (1) Initialize the node: Configure the network name (SSID), security settings (such as WPA3 encryption) and other basic network parameters for each self-organizing node.

[0103] (2) Enable HaLow mode: Ensure that each self-organizing node supports the HaLow standard and enable HaLow mode in its firmware settings.

[0104] Step 3: Establish a self-organizing network of drones;

[0105] (1) Configure Backhaul: Backhaul refers to the connection between self-organizing nodes. Under the HaLow protocol, these nodes will establish a wireless connection through the 840MHz frequency band.

[0106] (2) Configure routing: Self-organizing nodes need to configure routing information so that data packets can be transmitted effectively in the network. This is usually done automatically through dynamic routing protocols such as 802.11s.

[0107] Step 4: Connecting nodes;

[0108] (1) Scanning and discovery: The self-organizing node will periodically build a preferred neighbor list based on the links obtained in step one, and search for other self-organizing nodes to establish connections.

[0109] (2) Connection and synchronization: Nodes establish connections through the HaLow protocol and synchronize time and frequency.

[0110] Step 5: Optimize and adjust;

[0111] (1) Channel selection: Each UAV selects the best wireless channel based on its own connectivity to reduce interference and improve network performance.

[0112] (2) Adjust power and coverage: Each UAV adjusts its transmission power according to the actual environment and the distance between nodes to optimize coverage and network performance.

[0113] 3.2 High-frequency data link networking method;

[0114] As an additional greedy implementation, this embodiment proposes a high-frequency data link construction method based on control information. After each timestamp, the UAV performs a link establishment with optimal efficiency. By using this method, the UAV can maintain a fully connected network and maintain efficient data transmission during service execution. The specific implementation idea is as follows: First, we obtain information such as the number, location, and movement trajectory of UAVs in the global network based on control information. Then, an initial high-frequency data link is established at a lower power, and the differences between the network formed by UAVs communicating at maximum power and the initial link are evaluated to obtain the optional link set L.

[0115] As an incremental, greedy implementation, one link is added in each round to ensure that this link maximizes its utility and reduces overall network latency. The link utility function is: Where k+1 represents the (k+1)th iteration in establishing the link, T represents the utility function for adding the (k+1)th critical edge. k Let $k$ be the average path delay of the entire network in the kth iteration. Adding a remote link to the drone communication network The overall network average path delay when establishing a remote link between nodes i and j. Let $\frac{i}{j}$ be the construction cost of the remote link from node $i$ to node $j$. All such links belong to the optional link set $L$, and these links are removed from $L$ until no link can improve the utility function or $L$ is an empty set. Based on the above analysis, the construction methods for high-frequency data links based on control information are shown in Table 1. Due to latency requirements, For a set of high-frequency data links, k is the number of iterations (the number of additional links built).

[0116] Table 1

[0117]

[0118] Figure 3 is a schematic diagram of the initial high-frequency data link network of the embodiment; Figure 4 is a schematic diagram of the optimized high-frequency data link network of the embodiment.

[0119] The main innovations in this embodiment are: (1) a high-frequency dual-frequency link UAV networking architecture based on the separation of control link and high-frequency data link; (2) two networking methods for control link and high-frequency data link, the first group is a fully distributed networking method for control link, and the second group is a high-frequency data link networking method based on control information.

[0120] 4. Simulation Results

[0121] This embodiment simulates the networking process of multiple unmanned aerial vehicles (UAVs) in low-altitude urban areas. The experimental simulation scenario is 1000m. 1000m In a 200m urban scenario, 16 drones are initially randomly distributed throughout the scene. The movement model references a Markov movement model, with the drones' initial positions also randomly distributed. Based on the simulation environment of this embodiment, the network simulation parameters are shown in Table 2 below.

[0122] Table 2

[0123]

[0124] Example 2

[0125] Based on the same inventive concept, this embodiment also provides a low-altitude unmanned aerial vehicle (UAV) swarm dual-frequency link emergency networking system, including:

[0126] The first link construction module is used to construct the low-frequency control link of the low-altitude UAV, wherein the low-frequency control link adopts a fully distributed control link networking mode.

[0127] The information acquisition module is used to obtain global information of the control link by sharing network control data through the low-frequency control link, wherein the global information includes UAV positioning information, physical environment and communication resources;

[0128] The second link construction module is used to construct a high-frequency data link based on the global information and to transmit data through the high-frequency data link;

[0129] The dual-frequency link emergency networking module is used to build a dual-frequency link emergency network based on the low-frequency control link and the high-frequency data link, using a combination of high and low frequencies.

[0130] The low-altitude unmanned aerial vehicle (UAV) swarm dual-frequency link emergency networking system provided in this embodiment has all the advantages of the low-altitude UAV swarm dual-frequency link emergency networking method provided in Embodiment 1.

[0131] Example 3

[0132] This embodiment also discloses a computer device, including a memory, a processor, and a computer program stored in the memory, wherein the processor executes the computer program to implement the steps of the method described in Embodiment 1.

[0133] Example 4

[0134] This embodiment also discloses a computer-readable storage medium storing a computer program thereon, which, when executed by a processor, implements the steps of the method described in Embodiment 1.

[0135] Example 5

[0136] This embodiment also discloses a computer program product, including a computer program that, when executed by a processor, implements the steps of the method described in Embodiment 1.

[0137] The above are merely preferred embodiments of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A method for emergency networking of low-altitude unmanned aerial vehicle (UAV) swarms using dual-frequency links, characterized in that, Includes the following steps: A low-frequency control link for low-altitude unmanned aerial vehicles (UAVs) is constructed, wherein the low-frequency control link adopts a fully distributed control link networking mode. The construction of the low-frequency control link for low-altitude UAVs includes: each UAV broadcasting its own information at maximum power, exchanging this information to obtain information about surrounding UAVs; pairing links between UAVs based on the surrounding UAV information and constructing the low-frequency control link for the low-altitude UAVs; sharing network control data through the low-frequency control link to obtain global information of the control link, wherein the global information includes UAV positioning information, physical environment, and communication resources; and constructing a high-frequency data link based on the global information for data transmission. The high-frequency data link construction method includes: for each time slot t; initializing the UAV set. Establishing initial network connections: This is achieved by establishing links with signal strength greater than pth and obtaining a set of high-frequency data links. ;Evaluate the network composed of all UAVs communicating at maximum power and compare it with the initial link to derive the optional link set L;When At that time, traverse each link in the optional link set L. ,in Due to latency requirements, k is the iteration number; traverse each link in L, and calculate the utility function of adding that link, i.e. Where k+1 represents the (k+1)th iteration in establishing the link, Let Tk represent the utility function for adding the (k+1)th critical edge, and Tk be the average path delay of the entire network in the kth iteration. Adding a remote link to the drone communication network The overall network average path delay at that time Let L be the construction cost of a remote link from node i to node j; find the link with the highest utility function among the links belonging to L, i.e. ; Determine if adding this link is less than the utility function of the current iteration or if the set L is not empty. If the loop ends, the network topology decision is output; otherwise, the link is added to the high-frequency data link set. Remove the link from set L and increment the iteration count by 1. 、 k=k+1, and the network topology is updated simultaneously; based on the low-frequency control link and high-frequency data link, a dual-frequency link emergency network is built using a combination of high and low frequencies; the urban low-altitude channel model includes: assuming the scenario is a system composed of T extremely short timestamps, where Then, for each timestamp t, the drone is static; let the drone's coordinates at time t be... The distance between drone a and drone b is The channel gain between UAV a and UAV b can be expressed as: Where β represents the large-scale fading factor; h is the small-scale fading factor, and its expected value is 1, i.e. When designing a UAV-based communication system, the randomness generated by line-of-sight (LAS) and non-LAS links must be considered. For air-to-air communication, the probability of LAS wireless transmission between UAV a and UAV b is modeled based on the environment, the positions of the UAVs, and their elevation angles. Where C and D represent the propagation parameters and constant values, Indicates the elevation angle; in addition, the channel gain of the UAV equipment is introduced: ; where f c For the carrier frequency, f is the low-frequency control link. c The value is 840MHz, which is suitable for high-frequency data links. c The value is set to 2.4 GHz, α is the path loss exponent, η1 and η2 are the additional path loss coefficients for full line-of-sight transmission and non-line-of-sight transmission respectively, and c is the speed of light; the channel gain determined by full line-of-sight transmission and non-line-of-sight transmission can be corrected as follows: Among them, the regularized full line-of-sight transmission probability is: ， The channel gain is expressed as follows: when the distance is 1; the signal power received by UAV a from UAV b can be expressed as: Where pr is the received power and pt is the transmitted power; meanwhile, the transmission rate between UAVs can be expressed as: 。 2. The emergency networking method for low-altitude unmanned aerial vehicle (UAV) swarms with dual-frequency links according to claim 1, characterized in that, The low-frequency control link uses a networking module that supports the Wifi Halow protocol, with a frequency band of 840MHz.

3. The emergency networking method for low-altitude unmanned aerial vehicle (UAV) swarms with dual-frequency links according to claim 1, characterized in that, It also includes a channel model based on probabilistic line-of-sight wireless transmission, and obtains the average path loss for direct communication between drones based on the impact of building obstruction on signal propagation between drones.

4. The emergency networking method for low-altitude unmanned aerial vehicle (UAV) swarms with dual-frequency links according to claim 1, characterized in that, It also includes the process of optimizing the dual-frequency link emergency networking: selecting different transmission carrier frequencies according to the transmission needs of different types of information from drones; and adjusting the transmission power according to the actual environment of each drone and the distance between nodes to build a transmission link.

5. A dual-frequency link emergency networking system for low-altitude unmanned aerial vehicle (UAV) swarms, characterized in that, The method for implementing any one of claims 1-4 comprises: a first link construction module for constructing a low-frequency control link for a low-altitude unmanned aerial vehicle (UAV), wherein the low-frequency control link adopts a fully distributed control link networking mode; an information acquisition module for obtaining global information of the control link by sharing network control data through the low-frequency control link, wherein the global information includes UAV positioning information, physical environment, and communication resources; a second link construction module for constructing a high-frequency data link based on the global information, and transmitting data through the high-frequency data link; and a dual-frequency link emergency networking construction module for constructing a dual-frequency link emergency network based on the low-frequency control link and the high-frequency data link, using a combination of high and low frequencies.

6. A computer device comprising a memory, a processor, and a computer program stored in the memory, characterized in that, The processor executes the computer program to implement the steps of the method according to any one of claims 1-4.

7. A computer-readable storage medium having a computer program stored thereon, characterized in that, When executed by a processor, the computer program implements the steps of the method according to any one of claims 1-4.

8. A computer program product, comprising a computer program, characterized in that, When executed by a processor, the computer program implements the steps of the method according to any one of claims 1-4.

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