UAV swarm network access management and center frequency migration control method and system

Abstract

The present invention relates to the field of unmanned aerial vehicle communication technology, and discloses a method and system for unmanned aerial vehicle group network access management and center frequency migration control to improve anti-interference capability. The method includes: a central node sets and dynamically updates a legal network access node identification table; the central node identifies whether there are illegal task nodes according to the legal network access node identification table, and after identifying the existence of illegal task nodes, determines whether to perform center frequency migration processing according to the frequency of occurrence of illegal task nodes within a set time period; if the center frequency migration processing is performed, the central node sends a new center frequency selected in a random manner from a preset migration center frequency table to all network access task nodes; wherein, the number of center frequencies that can be synchronously switched by each node in the same unmanned aerial vehicle group in the center frequency table is at least three.

Description

Technical Field

[0001] The present invention relates to the field of unmanned aerial vehicle communication technology, and in particular to a method and system for managing the network access of a group of unmanned aerial vehicles and controlling the center frequency migration. Background Art

[0002] Wireless communication and ad hoc networking technologies are the basis for the automation and intelligence of unmanned equipment, and are the key links for unmanned equipment to complete group tasks. The unmanned cluster control in current engineering applications generally still uses a centralized network, that is, the central node performs communication control, cluster task generation, task binding, status monitoring and situation awareness fusion, etc.; each task node independently completes the bound task and transmits back its own status information and collected situation information. Unlike traditional wireless links such as radio stations, in order to ensure the security and reliability of communication, drone swarms need to adopt effective network access control and intra-network collaborative control. Unlike wireless communication technologies such as 5G, there are fewer frequency band resources suitable for drone swarm communications, and the real-time requirements for communication links are high. It is not suitable for anti-interference through high-frequency frequency hopping spread spectrum with a large bandwidth.

[0003] Due to the large transmission distance of the data link, in the same area, there may be new nodes in the drone swarm joining the network, or new nodes in other drone swarms may mistakenly send network access requests to the drone swarm. At the same time, other networked drone swarms may use the data link with the same center frequency as the local swarm, causing interference in data transmission. Therefore, it is necessary to perform network access management and anti-interference communication control on the drone swarm to ensure reliable and stable data transmission within the drone swarm.

[0004] In the current drone cluster communication control, only the situation where the link is interfered or new nodes enter or old nodes exit the link is often considered. There is no means to deal with the situation where drones or drone groups other than the drone group appear in the communication range of the drone group in complex application scenarios. In the case of link interference, the anti-interference function is generally achieved directly through high-speed frequency hopping. There are also methods to achieve anti-interference by actively sensing interference and then carrying out frequency hopping. However, this method is only applicable to drone groups without central networking. It requires all drone groups to pre-prepare frequency hopping maps in advance and work with high-precision hardware timing equipment to achieve it. It is difficult to achieve and has low security. In the case of new nodes entering or old nodes exiting, drone group communication control generally only considers how to allocate network resources, but does not judge whether the new drone applying for network access is a drone allowed by the network. This leads to the problem of drones other than the drone group mistakenly entering the drone group network. Summary of the invention

[0005] The present invention aims to disclose a method and system for managing the network access of a group of drones and controlling the center frequency migration, so as to improve the anti-interference capability.

[0006] To achieve the above-mentioned purpose, the method for managing the access of drone groups to the network and controlling the center frequency migration disclosed in the present invention includes:

[0007] The central node sets and dynamically updates the legal network access node identification table;

[0008] The central node identifies whether there are illegal task nodes based on the legal network access node identification table, and after identifying the existence of illegal task nodes, determines whether to perform center frequency migration processing based on the frequency of occurrence of illegal task nodes within a set time period; if the center frequency migration processing is performed, the central node sends a new center frequency selected in a random manner from a preset migration center frequency table to all network access task nodes; wherein, the number of center frequencies that can be synchronously switched by each node in the same drone group in the center frequency table is at least three.

[0009] Preferably, when the occurrence frequency of illegal task nodes within a set time period is greater than a set first quantity threshold, the center frequency migration control process is directly started.

[0010] Preferably, when the occurrence frequency of illegal task nodes within a set time period is greater than 1 and less than the set first quantity threshold, it is determined whether the number of nodes in the drone swarm that are higher than the current background noise is greater than the set second quantity threshold. If the judgment result is greater than, the center frequency migration control process is started; otherwise, the occurrence frequency of illegal task nodes within the set time period and the changes in the number of nodes in the drone swarm that are higher than the current background noise are continued to be tracked.

[0011] Preferably, the central node parses the identifier of the sender node from the received network access application. If the identifier is not in the legal network access node identifier table, the sender node is judged to be an illegal task node and an instruction carrying "network access not allowed" information is sent to the sender node.

[0012] Preferably, the uplink data frame in which the central node interacts with each of the task nodes includes a node type identifier, a target machine identifier, a network access permission instruction, a center frequency migration instruction, and information on migration to a new center frequency; the downlink data frame includes: a node type identifier, a local machine identifier, a background noise value, a network access status, and feedback information on whether the center frequency migration instruction has been received.

[0013] Preferably, after migrating to the new central frequency, each of the task nodes sets the network access status to "not in the network" in the downlink data frame, so as to re-interact with the central node in the network based on the new central frequency.

[0014] Preferably, after receiving the center frequency migration instruction and before migrating to the new center frequency, each task node continuously replies to the central node with 3 frames of feedback information of receiving the center frequency migration instruction at the current center frequency, so that the central node can perform its own center frequency migration processing after confirming that all task nodes have received the feedback of the center frequency migration instruction. Furthermore, if the central node fails to collect feedback that all task nodes have received the center frequency migration instruction within the set time interval, it will start its own center frequency migration processing after sending 3 consecutive frames of center frequency migration instructions again.

[0015] To achieve the above-mentioned objectives, the present invention also discloses a drone swarm network access management and center frequency migration control system, including a central node and a task node; each node is respectively deployed with a memory, a processor, and a computer program stored in the memory and executable on the processor, and the processors corresponding to the interactive central node and the task node respectively execute corresponding computer programs to collaboratively implement the above-mentioned method.

[0016] The present invention has the following beneficial effects:

[0017] In a drone swarm, the central node makes a legitimacy judgment on the nodes within the communication coverage based on the legal network access node identification table, and can dynamically instruct each task node to synchronously perform frequency migration based on the migration center frequency table, thereby ensuring the normal network access of legal task nodes and preventing illegal task nodes from accessing the network, and ensuring a high anti-interference capability, thereby preventing other drone swarms within the communication coverage from causing communication interference to the drone swarm. In addition, the present invention does not require an external timing device and is simple to implement.

[0018] The present invention will be further described in detail below with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The drawings constituting a part of this application are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the drawings:

[0020] Figure 1 It is a flow chart of the method for managing the network access of a group of drones and controlling the center frequency migration disclosed in an embodiment of the present invention. DETAILED DESCRIPTION

[0021] The embodiments of the present invention are described in detail below with reference to the accompanying drawings, but the present invention can be implemented in many different ways as defined and covered by the claims.

[0022] Example 1

[0023] This embodiment takes a certain drone swarm as an example. The drone swarm includes a ground command and control terminal and eight drones, and adopts a central networking mechanism; the central node is identified as 001, and the task node identifiers are 101-108 respectively.

[0024] The ground command and control terminal is the central node of the drone swarm, responsible for leading communication control, cluster task calculation, task allocation, command generation and issuance, and feedback data reception and processing; an internal prefabricated "legal network access node identification table" is included, and its identification table contains 001 and 101~108; the internal preset "migration center frequency table" can be set in the form of a working frequency band range, preferably, the center frequency range can be set to: 1415MHz~1515MHz; when selecting a new center frequency, any integer value within the range can be selected randomly.

[0025] The drone is the drone swarm mission node, responsible for completing the cluster mission according to the instructions of the central node and feeding back its own status and situational awareness data.

[0026] Both the central node and the task node have the function of detecting the background noise of the local communication link.

[0027] The central node and the task node communicate through wireless channels, and the communication between them follows the communication control protocol and data transmission protocol.

[0028] The communication control uplink data packet specifies the communication control instruction information transmitted from the central node to the task node, and its frame format is shown in Table 1. The communication control downlink data packet specifies the communication status information transmitted from the task node to the central node, and its frame format is shown in Table 2. It at least contains the node type identification, the local identification, the background noise value, the network access status, and the received center frequency migration instruction, where the network access status defaults to "not connected to the network".

[0029] Table 1: Communication control uplink data packet frame format

[0030]

[0031] Table 2: Communication control downlink data packet frame format

[0032]

[0033] The method for managing the network access of a drone group and controlling the center frequency migration of the present embodiment is as follows:

[0034] Step 1: Task nodes apply for network access and central node network access judgment.

[0035] The central node receives and parses the communication control downlink data packet, determines whether the "network access status" of the task node is "not networked", and if it is "not networked", continues to determine whether the "local identification" of the task node is in the "legal network access node identification table". If it is in the "legal network access node identification table", the "local identification" of the task node is recorded as "networked task node", and generates a communication control uplink data packet according to the communication control protocol, wherein the "target machine identification" is set to the "local identification" of the task node, and the "network access permission instruction" is set to "network access allowed", and 3 frames of communication control uplink data packets are sent continuously; if it is not in the "legal network access node identification table", the "local identification" of the task node is recorded as "illegal task node", and generates a communication control uplink data packet according to the communication control protocol, wherein the "target machine identification" is set to the "local identification" of the task node, and the "network access permission instruction" is set to "network access not allowed", and 3 frames of communication control uplink data packets are sent continuously.

[0036] Step 2: The task node responds to the network access permission instruction.

[0037] The task node receives and parses the communication control uplink data packet, determines whether the "target machine identification" is the local machine identification, and if it is the local machine identification, determines whether the "network access permission instruction" is "network access is not allowed". If it is "network access is not allowed", no data will be sent within 60 seconds. After 60 seconds, it will start sending communication control downlink data packets again. If it is "network access is allowed", it will communicate with the central node according to the data transmission protocol.

[0038] Step 3: Prediction of non-local drone group network.

[0039] The time starts from the moment the first "illegal task node" is identified. If the second "illegal task node" is found within 60 seconds, it is determined that there is a non-local drone group within the communication coverage area ready to form a network, and steps 5 to 7 are executed; if the second "illegal task node" is not found within 60 seconds, the illegal task node record is cleared and step 4 is executed.

[0040] Step 4: Determine the noise floor of the communication link.

[0041] The central node monitors the local noise floor value, and receives and analyzes the communication control downlink data packets from the networked task nodes; it determines whether the noise floor of the local node and the networked task nodes are both lower than the threshold. If the noise floor of any of the nodes is higher than the threshold, proceed to step five; if the noise floor is lower than the threshold, proceed to step one.

[0042] Step 5: The central node generates a central frequency migration instruction.

[0043] The central node randomly generates a frequency point within the "allowed working frequency band range of this drone group" as the "migration center frequency point of this drone group"; generates a communication control uplink data packet according to the communication control protocol, in which the "node type identifier" is set to "central node", the "target machine identifier" is set to "all networked nodes", the "center frequency migration instruction" is set to "migration", and the "migration to frequency point" is set to "migration center frequency point of this drone group"; and sends 3 frames of communication control uplink data packets continuously.

[0044] Step 6: The task node performs central frequency migration.

[0045] All network-connected task nodes receive and parse the communication control uplink data packet, determine whether the "target machine identification" is "all network-connected nodes", and if it is "all network-connected nodes", determine whether the "center frequency migration instruction" is "migration". If it is "migration", a communication control downlink data packet is generated, in which the "node type identification" is set to "task node", the "local machine identification" is set to the "local machine identification" of this task node, and the "received center frequency migration instruction" is set to "received", and 3 frames of communication control downlink data packets are sent continuously; the "local center frequency" is set to the "migration center frequency of this drone group" to migrate the center frequency; the network access status of the communication control downlink data packet is set to "not connected to the network", and the communication control downlink data packet is sent periodically.

[0046] Step 7: The central node performs central frequency migration.

[0047] The central node receives and parses the communication control downlink data packets of each task node, and determines whether the "received center frequency migration instruction" is "received". If so, the "local identification" of the task node is recorded as "migrated task node"; it determines whether all task nodes that have joined the network have received the center frequency migration instruction. If so, the "local center frequency" is set to "the migration center frequency of this drone group" and executes step 1. Among them, the method for judging whether all task nodes that have joined the network have received the center frequency migration instruction is to compare the information of the migrated task node with the legal network node identification table in step 1. This is a prior art and will not be described in detail.

[0048] In rare special cases, if the central node does not collect feedback from all task nodes that they have received the central frequency migration instruction within the set time interval, it will start its own central frequency migration processing after sending 3 consecutive central frequency migration instructions again.

[0049] In summary, in this embodiment, the core content is as follows: Figure 1 As shown, including:

[0050] Step S1: The central node sets and dynamically updates the legal network access node identification table.

[0051] Step S2, the central node identifies whether there are illegal task nodes based on the legal network node identification table, and after identifying the existence of illegal task nodes, determines whether to execute the center frequency migration process based on the frequency of occurrence of illegal task nodes within a set time period; if the center frequency migration process is executed, the central node sends a new center frequency selected in a random manner from a preset migration center frequency table to all network task nodes; wherein, the number of center frequencies that can be synchronously switched by each node in the same drone group in the center frequency table is at least three.

[0052] Optionally, in step S2, when the frequency of occurrence of illegal task nodes in a set time period is greater than a set first quantity threshold, the center frequency migration control process is directly started. Alternatively, when the frequency of occurrence of illegal task nodes in a set time period is greater than 1 and less than the set first quantity threshold, it is determined whether the number of nodes in the drone group below the current background noise is greater than a set second quantity threshold (this value is usually 1, and as a degraded implementation, it can also be a natural number greater than or equal to 2). If the judgment result is greater than, the center frequency migration control process is started; otherwise, the frequency of occurrence of illegal task nodes in a set time period and the changes in the number of nodes in the drone group below the current background noise are continuously tracked.

[0053] In addition, the frequency, waveform and protocol of point-to-point communication must be consistent. When the drone swarm migrates to a new central frequency, the communication link between the illegal mission node and the central node is deemed to be cut off, thereby improving the anti-interference capability of the swarm through frequency modulation.

[0054] As a variation, when no ground command and control terminal is deployed in the drone swarm, a drone can also be designated as the central node. It is worth noting that the drone described in the present invention, in a non-whole machine semantic environment, essentially refers to the wireless communication module deployed on the drone. Each wireless communication module is a distributed networking node of the drone swarm. This is common sense that is obvious to those skilled in the art and will not be elaborated on later.

[0055] Example 2

[0056] The present embodiment discloses a drone swarm network access management and center frequency migration control system, including a central node and a task node; each node is respectively deployed with a memory, a processor, and a computer program stored in the memory and executable on the processor, and the processors corresponding to the interactive central node and the task node respectively execute corresponding computer programs to collaboratively implement the method disclosed in the above embodiment.

[0057] In summary, the drone swarm network access management and center frequency migration control method and system disclosed in the embodiments of the present invention, in the drone swarm, the central node makes a legitimacy judgment on the nodes within the communication coverage range based on the legal network access node identification table, and can dynamically instruct each task node to synchronously perform frequency migration based on the migration center frequency table, which not only ensures the normal network access of legal task nodes and prevents illegal task nodes from accessing the network, but also ensures a high anti-interference capability, preventing other drone swarms within the communication coverage range from causing communication interference to the drone swarm; and the present invention does not require an external timing device, and is simple to implement.

[0058] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A method for managing drone group access and controlling center frequency migration, characterized in that: include: The central node sets and dynamically updates the legal network access node identification table; The central node identifies whether there is an illegal task node according to the legal network access node identification table, and after identifying the existence of the illegal task node, determines whether to perform the center frequency migration process according to the frequency of occurrence of the illegal task node within a set time period; if the center frequency migration process is performed, the central node sends a new center frequency selected in a random manner from a preset migration center frequency table to all network access task nodes; wherein the number of center frequencies that can be synchronously switched by each node in the same drone group in the center frequency table is at least three; Among them, when the occurrence frequency of illegal task nodes in a set time period is greater than a set first quantity threshold, the center frequency migration control processing is directly started; when the occurrence frequency of illegal task nodes in a set time period is greater than 1 and less than the set first quantity threshold, it is judged whether the number of nodes in the drone swarm that are higher than the current background noise is greater than the set second quantity threshold. If the judgment result is greater than, the center frequency migration control processing is started; otherwise, the occurrence frequency of illegal task nodes in the set time period and the changes in the number of nodes in the drone swarm that are higher than the current background noise are continued to be tracked.

2. The method according to claim 1, characterized in that The central node parses the identifier of the sender node from the received network access application. If the identifier is not in the legal network access node identifier table, the central node determines that the sender node is an illegal task node and sends an instruction carrying "not allowed to access the network" information to the sender node.

3. The method according to claim 2, characterized in that The uplink data frame exchanged between the central node and each of the task nodes includes a node type identifier, a target machine identifier, a network access permission instruction, a center frequency migration instruction, and information on migration to a new center frequency; The downlink data frame includes: node type identification, local identification, background noise value, network access status and feedback information on whether the center frequency migration instruction has been received.

4. The method according to claim 3, characterized in that After migrating to the new central frequency, each of the task nodes sets the network access status to "not in the network" in the downlink data frame, so as to re-interact with the central node in the network based on the new central frequency.

5. The method according to claim 4, characterized in that After receiving the center frequency migration instruction and before migrating to the new center frequency, each task node continuously replies to the central node with 3 frames of feedback information on receiving the center frequency migration instruction at the current center frequency, so that the central node can perform its own center frequency migration processing after confirming that all task nodes have received the feedback of the center frequency migration instruction.

6. The method according to claim 5, characterized in that When the central node fails to collect feedback that all task nodes have received the central frequency migration instruction within the set time interval, the central node starts its own central frequency migration processing after sending 3 consecutive frames of central frequency migration instructions again.

7. A drone group network access management and center frequency migration control system, including a center node and a task node, characterized in that: Each node is respectively deployed with a memory, a processor, and a computer program stored in the memory and executable on the processor. The processors corresponding to the interactive central node and the task node respectively execute the corresponding computer programs to collaboratively implement any of the methods described in claims 1 to 6 above.

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