A distributed unmanned self-organizing network full node information synchronization method based on time-sharing activation scheduling

Abstract

The application discloses a kind of distributed unmanned self-organizing network full node information synchronization methods based on time-sharing activation scheduling, it belongs to wireless communication technical field.The application solves the problem of large communication overhead and low synchronization efficiency of traditional node information synchronization method.The application utilizes effective time division to form strict working time sequence, to ensure that node is controlled flooding in the process of broadcast propagation, utilizes time sequence division and the distributed activation, sleep scheduling rule of node, significantly reduces network overhead.Add the information of the node in the process of design node propagation forwarding message, so that the flooding message originally carries the full information of source node and routing node, makes full use of packet resources;Design the distributed activation, sleep strategy of node, utilize the information of other nodes from flooding message stored in node, in each time sequence with distributed mode control node activation or sleep, unnecessary node in sleep time sequence.The method of the application can be applied to full node information synchronization in network.

Description

Technical Field

[0001] This invention belongs to the field of wireless communication technology, specifically relating to a method for synchronizing information across all nodes in a distributed unmanned self-organizing network based on time-division activation scheduling. Background Technology

[0002] Unmanned ad hoc networks (UAVs), as a network structure that requires no fixed infrastructure and allows nodes to communicate autonomously, have been widely used in disaster relief, unmanned swarm collaborative operations, and other scenarios. In these networks, broadcasting or flooding is typically used to disseminate node information throughout the network to achieve full node synchronization. However, due to the dense node density and frequent node movement in UAVs, the network topology exhibits highly dynamic characteristics. This leads to problems such as a surge in data packet volume, severe duplicate forwarding, and network congestion in traditional node information synchronization methods, increasing communication overhead and affecting synchronization efficiency. Therefore, effectively controlling network load and communication overhead while ensuring complete information synchronization is a key issue in current UAV research. Summary of the Invention

[0003] The purpose of this invention is to solve the problems of high communication overhead and low synchronization efficiency of traditional node information synchronization methods, and to propose a distributed unmanned self-organizing network full node information synchronization method based on time-sharing activation scheduling.

[0004] The technical solution adopted by this invention to solve the above-mentioned technical problems is: a method for synchronizing information of all nodes in a distributed unmanned self-organizing network based on time-sharing activation scheduling, the method specifically including the following steps:

[0005] Step 1: The entire information synchronization process includes two phases in sequence: diffusion and exchange. The timing of the diffusion and exchange phases is then determined based on the total number of nodes N in the input undirected connected graph.

[0006] The time sequence division is specifically as follows:

[0007] The entire diffusion phase is defined as a diffusion time frame, which contains N subframes, and each subframe contains N-1 time slots; the entire switching phase is defined as a switching time frame, which contains one request time slot and one response time slot.

[0008] Step 2: Initialize the subframe sequence number n=1;

[0009] Step 3: Determine the state of each node within the nth subframe;

[0010] Step 4: Synchronize messages based on the state of each node in the undirected connected graph;

[0011] Step 5: Set the subframe number n = n + 1, and determine whether the subframe number n exceeds N;

[0012] If the subframe number n does not exceed N, then return to step three.

[0013] If the subframe sequence number n exceeds N, proceed to step six;

[0014] Step 6: During the request time slot of the exchange frame, each node checks the message list to determine whether it has synchronized the information of all nodes.

[0015] Nodes that have synchronized all node information will go to sleep in the requested time slot;

[0016] If a node that has not yet synchronized information with all nodes broadcasts a request message in the request time slot, then the node that receives the broadcast request message will broadcast the synchronization information it has collected in the response time slot, and the node that broadcasts the request message will receive the response information from its neighboring nodes.

[0017] Then proceed to step seven;

[0018] Step 7: Output the synchronization information collected by each node.

[0019] Furthermore, the clocks of each node in the undirected connected graph are synchronized.

[0020] Furthermore, the length of each time slot within the diffusion time frame and the switching time frame is the same.

[0021] Furthermore, the specific process of step three is as follows:

[0022] For the nth subframe:

[0023] Step 3: 1. Initialize node index i = 1;

[0024] Step 3.2: Determine if i=n is satisfied;

[0025] If i=n, ​​then node i is active, and step 33 is executed.

[0026] If i≠n, then determine whether node i meets the sleep condition. If node i does not meet the sleep condition, then node i is in an active state. If node i meets the sleep condition, then node i sleeps in the nth subframe. After determining the state of node i, then execute the three-three procedure.

[0027] Step 33: Let i = i + 1, and then determine whether i exceeds N;

[0028] If i exceeds N, proceed to step four;

[0029] If i does not exceed N, then return to step 32.

[0030] Furthermore, determining whether node i meets the sleep condition specifically involves:

[0031] For node i, determine whether the routing record in node i's routing table meets the following conditions: there exists at least one subframe whose corresponding path in node i's routing record contains both node i and node n, and node n appears before node i in every path in node i's routing record.

[0032] If the routing record in the routing table of node i meets the conditions, then node i meets the dormancy condition; otherwise, node i does not meet the dormancy condition.

[0033] Furthermore, the specific process of step four is as follows:

[0034] Step 4: 1. Initialize the time slot number p=1. Node n broadcasts a message in the first time slot and then goes to sleep.

[0035] Step 4.2: Determine if node i satisfies the following conditions: node i is a neighbor node of the broadcast node in the p-th time slot and node i is in an active state;

[0036] If the conditions are met, node i records the synchronization information in the broadcast message, and then fills in the local information table of node i based on the synchronization information.

[0037] If the condition is not met, then node i does not need to be processed;

[0038] Step 43: Let time slot p = p + 1, and determine whether time slot p is greater than N - 1;

[0039] If time slot p is greater than N-1, then proceed to step five;

[0040] If time slot p is less than or equal to N-1, then the node that filled in the local information table in the (p-1)th time slot will start sleeping after broadcasting the message in the pth time slot;

[0041] Then return to step four two.

[0042] Furthermore, in step six, the broadcast request message only contains the sequence number of the node that sent the request message.

[0043] Furthermore, in step six, the node that broadcasts the request message and the node that receives the broadcast request message are in an active state during the response time slot, while other nodes are in a dormant state during the response time slot.

[0044] The beneficial effects of this invention are:

[0045] This invention utilizes effective time partitioning to form a strict working sequence, ensuring controlled flooding during node broadcast propagation, avoiding flooding loops that waste resources, and reducing unnecessary packet transmissions. By employing effective time partitioning and distributed activation and sleep scheduling rules for nodes, this invention significantly reduces network overhead during the synchronization of information across all nodes. The design incorporates node information during message propagation and forwarding, ensuring that the original flooded message carries complete information about the source and routing nodes, fully utilizing data packet resources. The distributed activation and sleep strategy utilizes information stored in the flooded message from other nodes to control node activation or sleep in a distributed manner across different time sequences, suspending unnecessary nodes in certain time sequences, further reducing packet transmissions and lowering network overhead.

[0046] The method of this invention can effectively improve the problems of excessive network overhead and network congestion in the process of synchronizing information of all nodes in unmanned self-organizing networks due to the high density of nodes and the high dynamics of network topology. It improves the efficiency of node information synchronization and lays a solid foundation for applications in related fields. Attached Figure Description

[0047] Figure 1 This is a flowchart of a method for synchronizing information across all nodes in a distributed unmanned self-organizing network based on time-sharing activation scheduling, according to the present invention.

[0048] Figure 2 This is a schematic diagram of the system timing partitioning structure;

[0049] Figure 3 This is a diagram of the structure of the diffusion message;

[0050] Figure 4 A diagram of the local information table for the node;

[0051] Figure 5 Simulation diagram of the number of data packets received during full node information synchronization;

[0052] Figure 6 This is a simulation diagram of the probability of information synchronization across all nodes. Detailed Implementation

[0053] Specific implementation method one: Combining Figure 1 This embodiment describes a method for synchronizing information across all nodes in a distributed unmanned self-organizing network based on time-sharing activation scheduling. The method specifically includes the following steps:

[0054] Step 1: The entire information synchronization process includes two phases in sequence: diffusion and exchange. The timing of the diffusion and exchange phases is then determined based on the total number of nodes N in the input undirected connected graph.

[0055] The time sequence division is specifically as follows:

[0056] like Figure 2 As shown, the entire diffusion phase is defined as a diffusion time frame, which contains N subframes, and each subframe contains N-1 time slots; the entire switching phase is defined as a switching time frame, which contains a request time slot and a response time slot.

[0057] Step 2: Initialize the subframe sequence number n=1;

[0058] Step 3: Determine the state of each node within the nth subframe;

[0059] Step 4: Synchronize messages based on the state of each node in the undirected connected graph;

[0060] Step 5: Set the subframe number n = n + 1, and determine whether the subframe number n exceeds N;

[0061] If the subframe number n does not exceed N, then return to step three.

[0062] If the subframe sequence number n exceeds N, proceed to step six;

[0063] Step 6: During the request time slot of the exchange frame, each node checks the message list to determine whether it has synchronized the information of all nodes.

[0064] Nodes that have synchronized all node information will go to sleep in the requested time slot;

[0065] If a node that has not yet synchronized the information of all nodes broadcasts a request message in the request time slot, then the node that receives the broadcast request message (i.e. the neighbor node of the node that broadcasts the request message) broadcasts the synchronization information it has collected in the response time slot, and the node that broadcasts the request message receives the information from the neighbor node's response.

[0066] Then proceed to step seven;

[0067] Step 7: Output the synchronization information collected by each node.

[0068] like Figure 3 In the network shown, the frame structure of the message used in the diffusion phase includes the source node, hop count, synchronization information of each node, routing information, and the node that sent the message. The source node indicates which node generated the message, the hop count indicates how many hops the message traversed, the synchronization information of each node indicates the synchronization messages collected from the source node and routing nodes in the message, the routing information indicates the path records of the source node and routing nodes for this message, and the current forwarding node is the node that generated or forwarded the message. For example... Figure 4The system displays the local information tables maintained by each node. The total number of packets received by a node shows the total number of messages received by the node in one synchronization. The number of sleeps during the diffusion phase indicates the total number of sleeps the node has during the diffusion phase of one synchronization. The synchronization information table shows the synchronization messages collected by the node from other nodes. The routing information table shows the set of paths recorded by the node to N subframes. Each node stores a maximum of 100 hops of path information in a single subframe. The hop count in the routing table records the number of hops from the node to each other.

[0069] Specific Implementation Method Two: This implementation method differs from Specific Implementation Method One in that the clocks of each node in the undirected connected graph are synchronized.

[0070] The other steps and parameters are the same as in Specific Implementation Method 1.

[0071] For any node in an undirected connected graph, the node can complete the sending and receiving of information within a time slot, and the node can distinguish information from different nodes. Furthermore, each node in the undirected connected graph is aware of the overall temporal sequence of the network, and the neighbor relationships of each node in the undirected connected graph are known.

[0072] Specific Implementation Method 3: This implementation method differs from Specific Implementation Method 1 or 2 in that each time slot within the diffusion time frame and the exchange time frame has the same length.

[0073] Other steps and parameters are the same as in specific implementation method one or two.

[0074] Specific Implementation Method Four: This implementation method differs from Specific Implementation Methods One to Three in that the specific process of step three is as follows:

[0075] For the nth subframe:

[0076] Step 3: 1. Initialize node index i = 1;

[0077] Step 3.2: Determine if i=n is satisfied;

[0078] If i=n, ​​then node i is active, and step 33 is executed.

[0079] If i≠n, then determine whether node i meets the sleep condition. If node i does not meet the sleep condition, then node i is in an active state. If node i meets the sleep condition, then node i sleeps in the nth subframe. After determining the state of node i, then execute the three-three procedure.

[0080] Step 33: Let i = i + 1, and then determine whether i exceeds N;

[0081] If i exceeds N, proceed to step four;

[0082] If i does not exceed N, then return to step 32.

[0083] The other steps and parameters are the same as those in one of the specific implementation methods one to three.

[0084] Specific Implementation Method Five: This implementation method differs from Specific Implementation Methods One to Four in that the determination of whether node i meets the sleep condition is specifically as follows:

[0085] For node i, determine whether the routing record in node i's routing table meets the following conditions: there exists at least one subframe whose corresponding path in node i's routing record contains both node i and node n, and node n appears before node i in every path in node i's routing record.

[0086] If the routing record in the routing table of node i meets the conditions, then node i meets the dormancy condition; otherwise, node i does not meet the dormancy condition.

[0087] The other steps and parameters are the same as those in one of the specific implementation methods one to four.

[0088] Specific Implementation Method Six: This implementation method differs from Specific Implementation Methods One to Five in that the specific process of step four is as follows:

[0089] Step 4: 1. Initialize the time slot number p=1. Node n broadcasts a message in the first time slot and then goes to sleep.

[0090] Step 4.2: Determine whether node i satisfies the following conditions (except for the node broadcasting the message in the p-th time slot, each node needs to be determined): Node i is a neighbor node of the broadcasting node in the p-th time slot and node i is in an active state.

[0091] If the conditions are met, node i records the synchronization information in the broadcast message, and then fills in the local information table of node i based on the synchronization information.

[0092] If the condition is not met, then node i does not need to be processed;

[0093] Step 43: Let time slot p = p + 1, and determine whether time slot p is greater than N - 1;

[0094] If time slot p is greater than N-1, then proceed to step five;

[0095] If time slot p is less than or equal to N-1, then the node that filled in the local information table in the (p-1)th time slot will start sleeping after broadcasting the message in the pth time slot;

[0096] Then return to step four two.

[0097] The other steps and parameters are the same as those in one of the specific implementation methods one to five.

[0098] Specific Implementation Method Seven: This implementation method differs from one of Specific Implementation Methods One to Six in that, in step six, the broadcast request message only contains the sequence number of the node that sent the request message.

[0099] The other steps and parameters are the same as those in one of the specific implementation methods one to six.

[0100] Specific Implementation Method Eight: This implementation method differs from any of Specific Implementation Methods One to Seven in that, in step six, the node broadcasting the request message and the node receiving the broadcast request message are in an active state during the response time slot, while other nodes are in a dormant state during the response time slot.

[0101] The other steps and parameters are the same as those in any of the specific implementation methods one to seven.

[0102] Simulation Research

[0103] This invention proposes a low-overhead distributed unmanned self-organizing network full-node information synchronization method based on time-sharing activation scheduling. Simulations use undirected connected networks with 4-20 nodes, with 50 undirected connected networks corresponding to each node number. Simulation results for the number of data packets received during full-node information synchronization are as follows: Figure 5 As shown, it can be seen that the average packet volume of nodes with the "non-essential node activation / sleep scheduling" module and the "switching phase" is less than that with only the "diffusion phase," and the addition of the "switching phase" only increases the number of data packets by a small amount, proving the effectiveness and practicality of the above modules; although the use of the "switching phase" increases the number of packets by a small amount, as... Figure 6 As shown in the simulation diagram of the full node information synchronization probability, the introduction of the "switching phase" improves the robustness of full node information synchronization and increases the probability of full node information synchronization. Therefore, the method of this invention can reduce the number of data packets in the network and lower network overhead while maintaining a high probability of full node information synchronization.

[0104] The above examples of the present invention are merely illustrative of the computational model and process of the present invention, and are not intended to limit the implementation of the present invention. Those skilled in the art will recognize that other variations or modifications can be made based on the above description. It is impossible to exhaustively list all possible implementations here. Any obvious variations or modifications derived from the technical solutions of the present invention are still within the scope of protection of the present invention.

Claims

1. A method for synchronizing information across all nodes in a distributed unmanned self-organizing network based on time-sharing activation scheduling, characterized in that, The method specifically includes the following steps: Step 1: The entire information synchronization process includes two phases: diffusion and exchange. Then, based on the total number of nodes in the input undirected connected graph... N Divide the diffusion phase and the exchange phase into time sequences; The time sequence division is specifically as follows: The entire diffusion phase is defined as a diffusion time frame, which contains... N There are 10 subframes, and each subframe contains 10 subframes. N -1 time slot; Defines the entire switching phase as a single switching time frame, which contains a request time slot and a response time slot; Step 2: Initialize subframe sequence numbers n= 1; Step 3: Determine the first n The state of each node within the subframe, specifically the process is as follows: For the n Subframe: Step 3.1 Initialize node sequence numbers i= 1; Step 3.2: Determine if the condition is met. i=n ; like i=n Then the node i To activate the process, proceed to step three. like i≠n Then determine the node i Whether the hibernation conditions are met, specifically: For nodes i Determine the node i Does the routing record in the routing table meet the condition that at least one subframe exists in the node? i Each path in the routing record contains nodes. i and nodes n And this subframe is in the node i The nodes in each path in the routing record n All appear in the node i Before; If node i If the routing records in the routing table meet the conditions, then the node i If the sleep condition is met, then the node... i The dormancy conditions are not met; If node i If the sleep conditions are not met, then the node... i If the node is in an active state, i If the sleep conditions are met, then the node... i In the n Sleep within subframe; determine node i After reaching the desired state, execute the three-three sequence; Step 33, Order i=i+ 1. Make another judgment i Does it exceed N ; like i Exceed N Then proceed to step four; like i Not exceeding N Then return to step three two; Step 4: Synchronize messages based on the state of each node in the undirected connected graph; Step 5: Set the subframe number n=n+ 1. Determine the subframe number n Does it exceed N ; If subframe sequence number n No more than N If so, return to step three; If subframe sequence number n Exceed N Then proceed to step six; Step 6: During the request time slot of the exchange frame, each node checks the message list to determine whether it has synchronized the information of all nodes. Nodes that have synchronized all node information will go to sleep in the requested time slot; If a node that has not yet synchronized information with all nodes broadcasts a request message in the request time slot, then the node that receives the broadcast request message will broadcast the synchronization information it has collected in the response time slot, and the node that broadcasts the request message will receive the response information from its neighboring nodes. Then proceed to step seven; Step 7: Output the synchronization information collected by each node.

2. The method for synchronizing information across all nodes in a distributed unmanned self-organizing network based on time-sharing activation scheduling as described in claim 1, characterized in that, The clocks of all nodes in the undirected connected graph are synchronized.

3. The method for synchronizing information across all nodes in a distributed unmanned self-organizing network based on time-sharing activation scheduling according to claim 2, characterized in that, Each time slot within the diffusion time frame and the switching time frame has the same length.

4. The method for synchronizing information across all nodes in a distributed unmanned self-organizing network based on time-sharing activation scheduling according to claim 3, characterized in that, The specific process of step four is as follows: Step 4.1 Initialize the time slot sequence number p =1, node n Broadcast the message in the first time slot and then sleep; Step 42: Determine the nodes i Does it satisfy: node i For the first p The neighboring nodes of the broadcast node in each time slot and the node i It is in an active state; If satisfied, then the node i Record the synchronization information in the broadcast message, and then fill in the node based on the synchronization information. i Local information table; If not satisfied, then node i No processing required; Step 43: Set time slots p = p +1, determine time slot p Is it greater than N -1; If time slot p Greater than N If the value is -1, then proceed to step five. If time slot p Less than or equal to N -1, then in the first... p Nodes that filled out the local information table within -1 time slot are in the... p After broadcasting a message in a time slot, it will begin to sleep. Then return to step four two.

5. The method for synchronizing information across all nodes in a distributed unmanned self-organizing network based on time-sharing activation scheduling according to claim 4, characterized in that, In step six, the broadcast request message contains only the sequence number of the node that sent the request message.

6. The method for synchronizing information across all nodes in a distributed unmanned self-organizing network based on time-sharing activation scheduling according to claim 5, characterized in that, In step six, the node that broadcasts the request message and the node that receives the request message are in an active state during the response time slot, while other nodes are in a dormant state during the response time slot.

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