A method for constructing a dynamic topology network of a drone swarm

Abstract

The application discloses a kind of construction methods of unmanned aerial vehicle swarm dynamic topology network, comprising: according to unmanned aerial vehicle communication load capacity, air node is divided into middle large unmanned aerial vehicle and small unmanned aerial vehicle;With middle large unmanned aerial vehicle as fixed cluster head, build first level relay network, with small unmanned aerial vehicle as cluster subnode, build lower layer swarm network;In lower layer swarm network, temporary cluster head is elected, and temporary cluster head is formed as the relay machine subcluster network;Through orthogonal frequency hopping pattern, bidirectional information interaction is carried out between first level relay network and subcluster network.This scheme can make unmanned aerial vehicle swarm establish dynamic topology structure, and efficiently utilize wireless spectrum resource, improve the network communication performance of unmanned aerial vehicle swarm.

Description

Technical Field

[0001] This invention relates to the field of unmanned aerial vehicle (UAV) ad hoc network technology, specifically to a method for constructing a dynamic topology network for a UAV swarm and a dynamic topology network for a UAV swarm. Background Technology

[0002] Currently, drone swarms mostly employ mobile ad hoc networking strategies, with network structures divided into two types: planar and hierarchical. In a planar structure, all drone nodes operate at the same level, and multi-hop communication links exist between any two communicating nodes, requiring routing algorithms for inter-node communication. The advantage of this method is its simple structure, enabling the even distribution of traffic across paths and achieving load balancing. However, planar network structures are easily affected by communication range, network size, and environment, limiting their application to smaller networks with simpler topologies. Furthermore, network overhead and latency increase with the number of nodes, making it difficult to guarantee effective maintenance of dynamic topologies and real-time service transmission. Hierarchical structures, on the other hand, divide all nodes into clusters. Each cluster contains a network administrator (cluster head) and several member nodes. The cluster head is responsible for the topology maintenance and resource management of the entire cluster subnetwork, while member nodes are only responsible for basic network services such as data transmission. Compared to planar structures, hierarchical structures support a larger number of network nodes and are easier to maintain for more complex dynamic topologies.

[0003] In practical applications, distributed, clustered networking methods utilize cluster head nodes for command and control through multi-hop communication. However, the high-speed movement of drones causes frequent changes in topology and disconnections between nodes, making the routing scheme with a fixed cluster head insufficient to adapt to the frequently changing network topology and unable to meet the requirements for efficient collaboration between heterogeneous platforms in specific task scenarios.

[0004] Therefore, a method for constructing a dynamic topology network for drone swarms is needed, which can establish fast and reliable communication links to match different business needs in scenarios where network topology changes frequently, and effectively complete the dynamic topology maintenance of dense nodes. Summary of the Invention

[0005] In view of the above problems, this solution proposes a method for constructing a dynamic topology network for UAV swarms. By combining fixed cluster heads and dynamic cluster heads, it has both the flexibility of dynamic cluster heads and the stability of fixed cluster heads. It can quickly establish reliable communication links in response to changes in network topology and perform real-time management and maintenance of dynamic network topology, enabling UAV swarms to cope with complex and ever-changing networking environments.

[0006] According to a first aspect of the present invention, a method for constructing a dynamic topology network for a drone swarm is provided. First, aerial nodes are divided into medium-to-large drones and small drones based on their communication payload capabilities. Then, a primary relay network is constructed using medium-to-large drones as fixed cluster heads, and a lower-level swarm network is constructed using small drones as cluster child nodes. Next, temporary cluster heads are elected in the lower-level swarm network to form sub-cluster networks with these temporary cluster heads as relays. Finally, bidirectional information exchange is performed between the primary relay network and the sub-cluster networks using an orthogonal frequency hopping pattern.

[0007] Optionally, in the above method for constructing a dynamic topology network for UAV swarms, after medium and large UAVs are powered on, they perform channel sensing, synchronization, and neighbor discovery, elect fixed cluster heads that communicate with the ground station via single hops, and form a primary relay network; the number of sub-clusters in the lower-level swarm network is determined based on the number of fixed cluster heads in the primary relay network.

[0008] Optionally, in the above method for constructing a dynamic topology network for a drone swarm, one fixed cluster head in the primary relay network corresponds to two sub-cluster networks; each fixed cluster head simultaneously receives information sent by the two sub-cluster networks through a first orthogonal frequency hopping pattern and a second orthogonal frequency hopping pattern.

[0009] Optionally, in the above method for constructing a dynamic topology network for UAV swarms, small UAV nodes power on to perform channel awareness and form a set of available channels. Each small UAV node selects the channel with the smallest number in the channel set as its working channel. On the selected working channel, a hello packet is sent to discover neighbors, thereby completing the election of a temporary cluster head and the establishment of the sub-cluster network.

[0010] Optionally, in the above method for constructing a dynamic topology network for a drone swarm, the steps of sending hello packets on the selected working channel to perform neighbor discovery and complete the temporary cluster head election and the establishment of the sub-cluster network include:

[0011] Step 1: The small drone node sends and receives hello packets on the selected working channel. If it receives a hello packet from another node, it will treat that node as a neighbor node and update its own information table and neighbor information table.

[0012] Step 2: Upon receiving information from a new neighbor node, the node synchronously calculates the weights and updates the hello packet.

[0013] Step 3: If steps 1 and 2 continue for N superframes, proceed to step 4; otherwise, return to step 1, where N is the number of nodes in the sub-cluster network.

[0014] Step 4: The node queries its local neighbor node information table. If the node has no neighbor information, it is an isolated node and defaults to being the cluster head node, then proceeds to Step 5. If the node has neighbor information, it compares its own node weight with the minimum value among all neighbor nodes. If it is the unique minimum value among all neighbor nodes, it elects itself as the cluster head node and proceeds to Step 5. If the node's weight and the weight of its neighbor nodes are both the minimum values, it uses the minimum ID criterion (ID refers to the node number). If the node's ID value is smaller, it continues to elect itself as the cluster head and proceeds to Step 5; otherwise, it becomes a cluster child node and proceeds to Step 6. If it is not the minimum value among all neighbor nodes, it enters the member node state and proceeds to Step 6.

[0015] Step 5: The cluster head node periodically broadcasts reference frames;

[0016] Step 6: Cluster child nodes wait to receive reference frames. Nodes that receive reference frames broadcast by the cluster head send cluster entry request messages to the cluster head and proceed to step 7.

[0017] Step 7: If a cluster child node receives a confirmation message from the cluster head node after approval, the network entry is complete, and the node completes its local information table; otherwise, proceed to step 6.

[0018] Optionally, in the above method for constructing a dynamic topology network for a drone swarm, time-division duplex / time-division multiple access is used to allocate time slots for each node in the sub-cluster network. Each time frame period is divided into network maintenance time slots, relay forwarding time slots, relay reserved time slots, and service time slots. Each node in the sub-cluster network sends MAC control information, telemetry information, and coordination information in the network maintenance time slot, and transmits video service information in the service time slot. The temporary cluster head forwards the MAC control information, telemetry information, and coordination information sent by the nodes in the sub-cluster network to the fixed cluster head in the relay forwarding time slot and / or the relay reserved time slot.

[0019] Optionally, in the above method for constructing a dynamic topology network for drone swarms, when the network topology of the lower-level swarm network changes, the small drone nodes in each sub-cluster network re-elect a new temporary cluster leader; the small drone nodes in the sub-cluster network interact with the fixed cluster leader through the new temporary cluster leader.

[0020] According to a second aspect of the present invention, this solution provides a dynamic topology network for unmanned aerial vehicle (UAV) swarms, which can be constructed by the above-described method for constructing a dynamic topology network for UAV swarms. The system includes: a primary relay network with medium and large UAVs as fixed cluster heads and a sub-cluster network with small UAVs as temporary cluster heads. The small UAVs in the sub-cluster network are adapted to communicate with the fixed cluster heads through the temporary cluster heads.

[0021] Optionally, in the above-mentioned UAV swarm dynamic topology network, the fixed cluster head receives information sent by two sub-cluster networks simultaneously through the first orthogonal frequency hopping pattern and the second orthogonal frequency hopping pattern, and sends information to nodes within the cluster through the third orthogonal frequency hopping pattern.

[0022] According to the present invention, by combining fixed cluster heads and dynamic cluster heads, both the flexibility of dynamic cluster heads and the stability of fixed cluster heads are achieved. This enables the rapid establishment of reliable communication links in response to changes in network topology and allows for real-time management and maintenance of dynamic network topology, enabling UAV swarms to cope with complex and ever-changing networking environments.

[0023] The above description is merely an overview of the technical solution of the present invention. In order to better understand the technical means of the present invention and to implement it in accordance with the contents of the specification, and in order to make the above and other objects, features and advantages of the present invention more apparent and understandable, specific embodiments of the present invention are described below. Attached Figure Description

[0024] Various other advantages and benefits will become apparent to those skilled in the art upon reading the following detailed description of preferred embodiments. The accompanying drawings are for illustrative purposes only and are not intended to limit the invention. Furthermore, the same reference numerals denote the same parts throughout the drawings. In the drawings:

[0025] Figure 1 A flowchart illustrating a method 100 for constructing a dynamic topology network for a drone swarm according to an embodiment of the present invention is shown.

[0026] Figure 2 A schematic diagram of a drone swarm network communication link according to an embodiment of the present invention is shown. Detailed Implementation

[0027] Exemplary embodiments of the present disclosure will now be described in more detail with reference to the accompanying drawings. While exemplary embodiments of the present disclosure are shown in the drawings, it should be understood that the present disclosure may be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the disclosure to those skilled in the art.

[0028] In the hierarchical structure of an unmanned aerial vehicle (UAV) ad hoc network, all nodes are divided into clusters. Each cluster contains a cluster head and several member nodes. The cluster head is responsible for the topology maintenance and resource management of the network within the cluster, while the member nodes are responsible for basic services such as data transmission. If the cluster head remains fixed, some member nodes within a cluster, although suitable for relay communication, cannot relay communication because they are not cluster heads, thus delaying the combat opportunity of the UAV swarm.

[0029] To enable UAV swarms to adapt to changes in network topology and quickly establish reliable communication links, this solution provides a method for constructing dynamic topology networks for UAV swarms. By combining dynamic cluster heads with fixed cluster heads, the UAV swarm can adapt to complex and ever-changing networking environments and efficiently complete dynamic topology maintenance of closed nodes.

[0030] Figure 1 A flowchart illustrating a method 100 for constructing a dynamic topology network for a drone swarm according to an embodiment of the present invention is shown. Figure 1 As shown, the method 100 begins with step S110, which divides the airborne nodes into medium and large UAV nodes and small UAV nodes according to the communication payload capacity of the UAV.

[0031] Because the communication payloads that drones can carry vary in size, power consumption, and weight, a large number of aerial nodes can be divided into two categories: medium and large drone nodes and small drone nodes, based on the drone's communication payload capabilities.

[0032] Among them, medium and large UAVs refer to UAVs with an empty takeoff weight between 25 kg and 150 kg and a maximum payload weight greater than 10 kg, which can be used as communication relays to forward information; small UAVs refer to UAVs with an empty takeoff weight of no more than 25 kg and a maximum payload weight of no more than 10 kg, which can be used as mission aircraft to undertake tasks such as reconnaissance, tracking, early warning, and strike, and communicate with ground stations through communication relays.

[0033] Then, step S120 is executed to build a first-level relay network with medium and large drones as fixed cluster heads, and to build a lower-level swarm network with small drones as cluster child nodes.

[0034] After being powered on, medium and large-sized UAVs perform channel awareness, synchronization, and neighbor discovery, electing a fixed cluster head for single-hop communication with the ground station to form a primary relay network. The fixed cluster head can provide time slot allocation for nodes within the cluster, realize information forwarding between nodes within the cluster, and be responsible for the management of nodes entering and leaving the network and spectrum resource scheduling.

[0035] Each small drone can further construct a lower-level swarm network to perform collaborative information exchange, spectrum resource management, and network topology management. The number of clusters and sub-clusters within each cluster in the lower-level swarm network can be determined based on the number of fixed cluster heads in the primary relay network.

[0036] For example, if a primary relay network contains two fixed cluster heads, each using dual-link reception, then the lower-level cellular network needs to be divided into two clusters, each containing two sub-clusters. If a primary relay network contains four fixed cluster heads, then the lower-level cellular network needs to be divided into four clusters, each containing two sub-clusters.

[0037] Then, step S130 is executed to elect a temporary cluster head in the lower-level bee colony network and form a sub-cluster network with the temporary cluster head as the relay.

[0038] Specifically, after powering on, the small drones in the lower-level swarm network perform channel awareness and form a set of available channels. Each small drone node selects the channel with the smallest number in the channel set as its working channel. Subsequently, the small drone nodes send hello packets on the selected working channel to discover neighbors, and on this basis, cluster head election and the establishment of sub-cluster networks are completed.

[0039] The process of neighbors discovering the problem includes:

[0040] Step 1: The small drone node sends and receives hello packets on the selected working channel. If it receives a hello packet from another node, it will treat that node as a neighbor node and update its own information table and neighbor information table.

[0041] Step 2: Upon receiving information from a new neighbor node, the node synchronously calculates the weights and updates the hello packet.

[0042] Step 3: If steps 1 and 2 continue for N superframes, proceed to step 4; otherwise, return to step 1, where N is the number of nodes in the sub-cluster network.

[0043] Step 4: The node queries its local neighbor node information table. If the node has no neighbor information, it is an isolated node and defaults to being the cluster head node, then proceeds to Step 5. If the node has neighbor information, it compares its own node weight with the minimum value among all neighbor nodes. If it is the unique minimum value among all neighbor nodes, it elects itself as the cluster head node and proceeds to Step 5. If the node's weight and the weight of its neighbor nodes are both the minimum values, it uses the minimum ID criterion (ID refers to the node number). If the node's ID value is smaller, it continues to elect itself as the cluster head and proceeds to Step 5; otherwise, it becomes a cluster child node and proceeds to Step 6. If it is not the minimum value among all neighbor nodes, it enters the member node state and proceeds to Step 6.

[0044] Step 5: The cluster head node periodically broadcasts reference frames;

[0045] Step 6: Cluster child nodes wait to receive reference frames. Nodes that receive reference frames broadcast by the cluster head send cluster entry request messages to the cluster head and proceed to step 7.

[0046] Step 7: If a cluster child node receives a confirmation message from the cluster head node after approval, the network entry is complete, and the node completes its local information table; otherwise, proceed to step 6.

[0047] A cluster head representing the region is elected, and this cluster head only becomes the true temporary cluster head after being recognized by the permanent cluster head. Small drone nodes within the neighborhood join this temporary cluster head as members, completing the construction of the sub-cluster network to achieve collaborative communication within the sub-cluster network.

[0048] Figure 2 A schematic diagram of a drone swarm network communication link according to an embodiment of the present invention is shown. Figure 2 This paper illustrates a two-level relay UAV swarm network constructed using the UAV swarm dynamic topology network construction method provided by the present invention. The network consists of a primary relay network with medium to large UAVs as fixed cluster heads and a sub-cluster network with small UAVs as temporary cluster heads. Small UAVs within the sub-cluster network communicate with the fixed cluster heads through the temporary cluster heads.

[0049] like Figure 2 As shown, the primary relay network consists of four communication relay units. Two of these relay units serve as cluster head nodes (fixed cluster head 1 and fixed cluster head 2). The fixed cluster heads have high power and high receiving sensitivity, which can meet the relay forwarding requirements. The smaller UAV swarms, located further away from the fixed cluster heads, are divided into two clusters (cluster 1 and cluster 2) with 38 mission units per cluster. Each cluster is further divided into two sub-clusters (sub-cluster 1, sub-cluster 2, sub-cluster 3, and sub-cluster 4) with 19 mission units per sub-cluster. Each small UAV node can act as a mission unit, and the transmission power and performance of each mission unit are basically the same.

[0050] Each subcluster network can select a temporary cluster head to communicate with a fixed cluster head. Other task machines within this subcluster network communicate with the fixed relay network through the temporary cluster head.

[0051] Finally, step S140 is executed, in which bidirectional information exchange is performed between the primary relay network and the sub-cluster network through orthogonal frequency hopping patterns.

[0052] To avoid mutual interference during data transmission and reception, different orthogonal frequency hopping patterns can be used for information transmission and reception.

[0053] To improve network transmission efficiency and interference resistance, the fixed cluster head can employ dual-link data reception. That is, the fixed cluster head simultaneously receives information from two sub-cluster networks using a first orthogonal frequency hopping pattern and a second orthogonal frequency hopping pattern, and transmits information to nodes within the cluster using a third orthogonal frequency hopping pattern. (Refer to...) Figure 2 Cluster head 1 uses orthogonal frequency hopping patterns f1 and f2 for reception; cluster head 2 uses orthogonal frequency hopping patterns f3 and f4 for reception. The two cluster head nodes use orthogonal frequency hopping pattern f5 for time-division transmission, and the other two relays, as cluster head backup nodes, listen to the channel on orthogonal frequency hopping pattern f5.

[0054] Nodes within subclusters 1 and 2 simultaneously transmit information to the fixed cluster head via a temporary cluster head using orthogonal frequency hopping patterns f1 and f2, respectively. All nodes within the cluster receive information using orthogonal frequency hopping pattern f5 and the corresponding transmission pattern of the nodes within the subcluster. Similarly, nodes within subclusters 3 and 4 simultaneously transmit using orthogonal frequency hopping patterns f3 and f4, respectively. All nodes within the cluster receive information using orthogonal frequency hopping pattern f5 and the corresponding transmission pattern of the nodes within the subcluster. This five sets of orthogonal frequency hopping patterns enable flexible and rapid communication between the four subcluster networks and the two fixed cluster heads.

[0055] To improve the signal reception capability of medium and large UAVs and expand channel capacity, the fixed cluster head adopts dual-link reception. Therefore, time-division duplex / time-division multiple access can be used to allocate time slots for each node in the sub-cluster network. Each time frame period is divided into network maintenance time slots, relay forwarding time slots, relay reserved time slots, and service time slots, so that each task machine and temporary cluster head can transmit information within the allocated time slots.

[0056] Time Division Multiple Access (TDMA) divides time into periodic frames, and each frame is further divided into several time slots. A channel consists of one periodic time slot, and multiple nodes can share the same frequency. Figure 2 Taking the UAV swarm network communication link shown as an example, time slot allocation planning is performed. Table 1 shows the time slot allocation table for nodes within a sub-cluster network according to an embodiment of the present invention.

[0057]

[0058]

[0059]

[0060] The cluster consists of two sub-clusters with a total of 19 pairs of nodes. Each pair of nodes transmits information simultaneously in a fixed time slot (using two sets of orthogonal frequency hopping sequences). As shown in Table 1 above, within each time frame period, a total of 22 time slots, from time slot 0 to time slot 21, are fixedly occupied. The first 19 time slots are network maintenance time slots. Nodes within the sub-cluster transmit MAC control information, telemetry information, and coordination information in the network maintenance time slots, and transmit video service information, PHY control information, etc., in the service time slots.

[0061] Temporary cluster heads forward MAC control, telemetry, and coordination information sent by nodes within the subcluster network to fixed cluster heads in relay forwarding time slots and / or relay reserved time slots. As shown in Table 1, temporary cluster head nodes in time slots 20-21 are used to relay inter-cluster information, and high reliability can be achieved by configuring repeated transmissions. Time slots 22-23 are relay reserved time slots, which can be used as needed according to the number of relay task machines. Time slots 24-77, a total of 54 time slots, are service and PHY control time slots used to transmit image or video service information and PHY control information, etc. In this way, task machine information transmission and relay machine communication can proceed in an orderly manner.

[0062] The following is an explanation of each time slot mentioned above:

[0063] Fixed time slot: Each node occupies 1 time slot for sending network maintenance information such as remote control, telemetry, coordination, and MAC data link layer control. It is sent in time frames. Each node / time slot can achieve a low-rate control signaling rate (e.g., 80Kbps). High reliability can be obtained by configuring repeated transmission.

[0064] Relay reserved time slots: Two time slots are reserved, and relay task machine nodes can occupy them as needed;

[0065] Relay forwarding time slot: Each cluster head occupies 1 time slot, which can achieve a low rate of control signaling (e.g., 80Kbps) and can obtain high reliability by configuring repeated transmission.

[0066] PHY control time slot: 200ms period, sending frequency hopping synchronization sequence, occupying two time slots.

[0067] Service time slots: Node scheduling within the sub-cluster is dynamically allocated to ensure one video stream. With 54 service time slots, a high-speed (e.g., 6Mbsp) service rate can be achieved, and theoretically, three video streams can be transmitted back.

[0068] It should be noted that the selection of the temporary cluster leader is dynamic. When the network topology of the lower-level swarm network changes, the small drone nodes within each sub-cluster network re-elect a new temporary cluster leader. The small drone nodes within the sub-cluster network then exchange information with the permanent cluster leader through the new temporary cluster leader.

[0069] The method for constructing a dynamic topology network for UAV swarms provided by the present invention can effectively maintain the dynamic topology of dense nodes by combining fixed cluster heads and temporary cluster heads and updating the temporary cluster heads in real time according to the network topology; and can reduce interference between channels by using multiple sets of orthogonal frequency hopping patterns to achieve bidirectional uplink and downlink communication.

[0070] Numerous specific details are set forth in the specification provided herein. However, it will be understood that embodiments of the invention may be practiced without these specific details. In some instances, well-known methods, structures, and techniques have not been shown in detail so as not to obscure the understanding of this specification.

[0071] Similarly, it should be understood that, in order to streamline this disclosure and aid in understanding one or more of the various aspects of the invention, in the above description of exemplary embodiments of the invention, various features of the invention are sometimes grouped together in a single embodiment, figure, or description thereof. However, this method of disclosure should not be interpreted as reflecting an intention that the claimed invention requires more features than are expressly recited in each claim. Rather, as reflected in the following claims, inventive aspects lie in fewer than all features of a single foregoing disclosed embodiment. Therefore, the claims following the detailed description are hereby expressly incorporated into this detailed description, wherein each claim itself is a separate embodiment of the invention.

[0072] Those skilled in the art will understand that modules, units, or components of the devices disclosed in the examples herein can be arranged in the devices described in this embodiment, or alternatively, can be located in one or more devices different from the devices in this example. The modules in the foregoing examples can be combined into a single module or, in addition, can be divided into multiple sub-modules.

[0073] Those skilled in the art will understand that modules in the device of the embodiments can be adaptively changed and placed in one or more devices different from that embodiment. Modules, units, or components in the embodiments can be combined into a single module, unit, or component, and further, they can be divided into multiple sub-modules, sub-units, or sub-components. Except where at least some of such features and / or processes or units are mutually exclusive, any combination can be used to combine all features disclosed in this specification (including the accompanying claims, abstract, and drawings) and all processes or units of any method or device so disclosed. Unless expressly stated otherwise, each feature disclosed in this specification (including the accompanying claims, abstract, and drawings) may be replaced by an alternative feature that serves the same, equivalent, or similar purpose.

[0074] Furthermore, those skilled in the art will understand that although some embodiments described herein include certain features but not others included in other embodiments, combinations of features from different embodiments are intended to be within the scope of the invention and form different embodiments. For example, in the following claims, any of the claimed embodiments can be used in any combination.

[0075] Furthermore, some of the embodiments described herein are methods or combinations of method elements that can be implemented by a processor of a computer system or by other means of performing functions. Therefore, a processor having the necessary instructions for implementing a method or method element forms a means for implementing that method or method element. Furthermore, the elements of the apparatus embodiments herein are examples of means for implementing functions performed by elements for the purposes of carrying out the invention.

[0076] As used herein, unless otherwise specified, the use of ordinal numbers such as “first,” “second,” “third,” etc., to describe ordinary objects merely indicates different instances of similar objects and is not intended to imply that the objects being described must have a given order in time, space, ordering, or any other manner.

[0077] Although the invention has been described with respect to a limited number of embodiments, those skilled in the art will understand from the foregoing description that other embodiments are conceivable within the scope of the invention described herein. Furthermore, it should be noted that the language used in this specification has been chosen primarily for readability and edibility purposes, and not for the purpose of interpreting or limiting the subject matter of the invention. Therefore, many modifications and variations will be apparent to those skilled in the art without departing from the scope and spirit of the appended claims. The disclosure of the invention is illustrative rather than restrictive, and the scope of the invention is defined by the appended claims.

Claims

1. A method for constructing a dynamic topology network for a drone swarm, characterized in that, include: Based on the communication payload capacity of drones, aerial nodes are divided into medium and large drones and small drones. A primary relay network is constructed using medium to large-sized drones as fixed cluster heads, and a lower-level swarm network is constructed using small drones as cluster child nodes, including: After being powered on, medium and large-sized UAVs perform channel sensing, synchronization, and neighbor discovery, electing a fixed cluster head for single-hop communication with the ground station to form a primary relay network; The number of sub-clusters in the lower-level bee colony network is determined based on the number of fixed cluster heads in the primary relay network. In the lower-level bee colony network, a temporary cluster leader is elected to form a sub-cluster network with the temporary cluster leader as the relay. Bidirectional information exchange is achieved between the primary relay network and the sub-cluster network through orthogonal frequency hopping patterns.

2. The method for constructing a dynamic topology network for a drone swarm according to claim 1, characterized in that, The step of determining the number of sub-clusters in the lower-level bee colony network based on the number of fixed cluster heads in the primary relay network includes: In a primary relay network, one fixed cluster head corresponds to two sub-cluster networks; Each fixed cluster head simultaneously receives information from two sub-cluster networks via a first orthogonal frequency hopping pattern and a second orthogonal frequency hopping pattern.

3. The method for constructing a dynamic topology network for a drone swarm according to claim 1, characterized in that, The step of electing a temporary cluster leader in the lower-level bee colony network and forming a sub-cluster network with the temporary cluster leader as the relay includes: The small drone node is powered on to perform channel sensing and form a set of available channels. Each small drone node selects the channel with the smallest number in the channel set as the working channel. Hello packets are sent on the selected working channel to discover neighbors, complete the temporary cluster head election and the establishment of the sub-cluster network.

4. The method for constructing a dynamic topology network for a drone swarm according to claim 3, characterized in that, The steps of sending hello packets on the selected working channel for neighbor discovery, and completing the temporary cluster head election and sub-cluster network establishment include: Step 1: The small drone node sends and receives hello packets on the selected working channel. If it receives a hello packet from another small drone node, it will treat that small drone node as a neighbor node and update its own information table and neighbor information table. Step 2: The small drone node receives the new neighbor node information, synchronously calculates the weights and updates the hello packet; Step 3: If steps 1 and 2 continue for N superframes, proceed to step 4; otherwise, return to step 1, where N is the number of nodes in the sub-cluster network. Step 4: The small drone node queries its local neighbor information table. If the small drone node has no neighbor information, it is an isolated node and defaults to a temporary cluster head node, then proceeds to Step 5. If the small drone node has neighbor information, it compares its own node weight with the minimum value among all neighbor nodes. If it is the unique minimum value among all neighbor nodes, it elects itself as the temporary cluster head node and proceeds to Step 5. If the weight of the small drone node and the weight of a neighbor node are both the minimum values, it uses the minimum ID criterion (ID refers to the node number). If the ID value of the small drone node is smaller, it continues to elect itself as the temporary cluster head and proceeds to Step 5; otherwise, it becomes a cluster child node and proceeds to Step 6. If it is not the minimum ID value among all neighbor nodes, it enters the member node state and proceeds to Step 6. Step 5: The temporary cluster head node periodically broadcasts reference frames; Step 6: Cluster child nodes wait to receive reference frames. Small UAV nodes that receive the reference frames broadcast by the temporary cluster head send a cluster entry request message to the temporary cluster head and proceed to step 7. Step 7: If the cluster child node receives a network access confirmation message after approval from the temporary cluster head node, the network access is completed, and the small drone node completes its local information table; otherwise, proceed to step 6.

5. The method for constructing a dynamic topology network for a drone swarm according to claim 1, characterized in that, The step of performing bidirectional information exchange between the primary relay network and the subcluster network using orthogonal frequency hopping patterns includes: Time slots are allocated to each node in the subcluster network using time division duplex and / or time division multiple access, and each time frame period is divided into network maintenance time slots, relay forwarding time slots, relay reserved time slots, and service time slots; Each node in the sub-cluster network sends MAC control information, telemetry information, and coordination information in the network maintenance time slot, and transmits video service information in the service time slot. The temporary cluster head forwards MAC control information, telemetry information, and coordination information sent by nodes within the sub-cluster network to the fixed cluster head in the relay forwarding time slot and / or the relay reserved time slot.

6. The method for constructing a dynamic topology network for a drone swarm according to claim 1, characterized in that, The method includes: When the network topology of the lower-level bee colony network changes, the small drone nodes in each sub-cluster network re-elect a new temporary cluster leader; Small UAV nodes within the sub-cluster network interact with the fixed cluster head via a new temporary cluster head.

7. A dynamic topology network system for unmanned aerial vehicle (UAV) swarms, characterized in that, The system is suitable for construction using the method for constructing a dynamic topology network of drone swarms as described in any one of claims 1-6. The system includes: a primary relay network with medium and large drones as fixed cluster heads and a sub-cluster network with small drones as temporary cluster heads, wherein the small drones in the sub-cluster network are adapted to communicate with the fixed cluster heads through the temporary cluster heads.

8. The UAV swarm dynamic topology network system according to claim 7, characterized in that, The fixed cluster head simultaneously receives information from two sub-cluster networks through the first orthogonal frequency hopping pattern and the second orthogonal frequency hopping pattern, and sends information to nodes within the cluster through the third orthogonal frequency hopping pattern.

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