Mixed time slot allocation method and system suitable for high-dynamic network clustering management

Abstract

The invention belongs to the field of mixed time slot allocation suitable for high-dynamic network clustering management, and discloses a mixed time slot allocation method and system suitable for high-dynamic network clustering management. According to the method, research of a traditional planar network is converted into a hierarchical and hierarchical network, clustering design is carried out on all nodes in the network, and the clustering efficiency of the network is improved. Therefore, the collision rate in the two jumps is reduced. Broadcasting neighbor information in the hierarchical and hierarchical network, and according to the neighbor information and the weight values of each node, after obtaining the weight values, taking the node with the highest weight value in a preset range as a leader node, and taking the leader node as a core to construct a cluster sub-network; through the election of the leader node, the maintenance time of the cluster subnet can be kept longer, meanwhile, since the nodes in the preset range are uniformly managed by the leader node, the collision between the nodes can be effectively avoided, the method is popularized to the whole network, the collision rate is greatly reduced, the throughput is improved, and the requirements of dynamic expansion and high throughput of the system are met.

Description

Technical Field

[0001] The present invention belongs to the technical field of mobile ad hoc network communication, and particularly relates to a hybrid time slot allocation method and system suitable for high-dynamic network clustering management. Background Art

[0002] In a wireless environment where the positions of each node are updated in real time and dynamically, the network topology constructed by each node is updated and changed more frequently. At the same time, the real-time requirements of each node in a high-dynamic network environment and the high reliability of information transmission all put forward higher requirements for the communication quality of the nodes.

[0003] In an ad hoc network, the performance of the MAC protocol is particularly important, and among them, the TDMA protocol is one of the most commonly used MAC protocols. In most current studies, the design focuses on dynamic time slot allocation in a flat network. When the node scale is small, the flat network with equal levels of each node has certain research value. However, as the node scale increases, the disadvantages of the flat network are exposed. It has poor scalability, and as the number of nodes increases, the proportion of control overhead in the system also becomes larger and larger. Therefore, it is difficult for a flat network to adapt to a network with dynamic scale expansion. Some achievements have also been made in the research of dynamic time slot allocation. Its flexibility compared with the static time slot allocation algorithm has improved the throughput of the system. However, the time slot allocation of the dynamic allocation algorithm depends on the negotiation between nodes. In a high-dynamic environment, as the node scale increases, the collision rate of the dynamic allocation algorithm will increase greatly, which will instead lead to a decrease in the system throughput. With the sinking of network devices and the decrease in cost, the scale of each network in real life is also increasing day by day. The current design is difficult to meet the scalability of nodes in the network, and the designed idea is not applicable to the scenario of dynamic scale expansion of the network. Moreover, due to the lack of consideration of the impact of control overhead on the system, it is also difficult to meet the requirements of high throughput of the system.

[0004] It can be seen that the existing time slot allocation methods can no longer meet the dynamic expansion of the high-dynamic network environment and the requirements of high throughput of the system. Summary of the Invention

[0005] The present invention provides a hybrid time slot allocation method and system suitable for high-dynamic network clustering management to solve the technical problem that the existing time slot allocation methods can no longer meet the dynamic expansion of the high-dynamic network environment and the requirements of high throughput of the system.

[0006] To achieve the above object, the present invention adopts the following technical solutions: A hybrid time slot allocation method suitable for high-dynamic network clustering management includes: Construct a network model based on the situation information of each node in the highly dynamic network, and at the same time initialize the nodes in the initial network formation in the network model and the neighbor node information table; where each node in the highly dynamic network adopts a clustering design; Based on the weight values of each node calculated from the neighbor node information table, elect the leader node; The leader node allocates time slots to the nodes within the preset range of the leader node, and at the same time constructs a time slot allocation table; The leader node recommends a gateway node according to the neighbor node information table to achieve initial network formation; the gateway node is used to communicate with the remaining preset range clusters outside in the gateway communication frequency band; After the initial network formation is successful, data communication between each node in the network model is carried out according to the time slot allocation table.

[0007] Further, the constructing a network model based on the situation information of each node in the highly dynamic network, and at the same time initializing the nodes in the initial network formation in the network model and the neighbor node information table includes: Construct a network model based on the situation information of each node in the highly dynamic network, and at the same time divide the communication frequency band to obtain a communication frame structure; Based on the constructed network model, combined with the communication frame structure and the preset message structure, initialize the nodes in the initial network formation and the neighbor node information table; at the same time, initialize the neighbor node information table by broadcasting control messages.

[0008] Further, among them, The communication frequency band is divided into two frequency bands: the cluster communication frequency band and the gateway communication frequency band; among them, all nodes within two-hop clusters communicate in the cluster communication frequency band if they communicate within the cluster; if there is a need for communication between nodes of this two-hop cluster and external two-hop clusters, the recommended gateway node communicates in the gateway communication frequency band; The design process of the communication frame structure includes: a synchronization phase, a control phase, a fixed time slot allocation phase, a reserved time slot allocation phase, and an isolated node competition phase; The synchronization phase is used to make all nodes complete clock synchronization; The control phase is used for the formation and maintenance of the network topology; The fixed time slot allocation phase and the reserved time slot allocation phase are jointly used for collision-free data interaction between nodes; The isolated node competition phase is used for the quick access of isolated nodes.

[0009] Further, the weight values of each node are calculated based on the node degree, link survival time, average node distance, remaining energy, and load degree in the neighbor node information table. The specific formula is as follows:

[0010] In the formula, represents the node degree of the node with ID i, represents the normalized average link survival time, represents the normalized average node distance, represents the value after normalizing the remaining energy of the i-th node, represents the normalized load degree, , , , , respectively represent the weights corresponding to each parameter; then the weight value of the node with ID i is .

[0011] Furthermore, the specific steps for the election of the leader node are as follows: Each node broadcasts its weight value in sequence according to the node ID; after the weight values are broadcast in sequence, the node with the largest weight value within one-hop range is elected as the initially recommended leader node; If within the two-hop range of the initially recommended leader node: there is only one cluster leader, which is the initially recommended leader node, then the initially recommended leader node shakes hands with each two-hop node in sequence according to the order of its two-hop neighbor node information table; the initially recommended leader node within two hops sends a request for network access packet carrying the allocated time slot to request the node to access the network; for the node that receives the request for network access packet, if it detects no collision, it returns a request return packet and broadcasts the allocated time slot of this node within its one-hop range; if it detects that the time slot allocated to the initially recommended leader node has been occupied by other nodes, it returns a collision packet; the initially recommended leader node reallocates the nodes according to the collision packet; after all handshakes are successful, the initially recommended leader node becomes the cluster leader in the cluster within two hops, and the remaining nodes become ordinary cluster units under the jurisdiction of the cluster leader within two-hop range; and before the next regular update of the control packet, each node maintains its own time slot allocation; when a collision occurs, each node adjusts itself; There are other nodes that have already become cluster leaders within two hops: If there are other cluster leaders within the two-hop range outside the one-hop range of the currently initially recommended leader node, then a comparison is made at the moment of handshake: select the node with the larger weight value as the only cluster leader within two hops, and the other cluster leader with the smaller weight value merges into the cluster leader with the larger weight value. The cluster leader with the smaller weight value broadcasts a cluster dissolution packet to the nodes that have been confirmed to be networked within its two-hop range, and the nodes that receive the cluster dissolution packet become isolated nodes waiting for handshake or competition; There are non-leader nodes that have entered other clusters within two hops: within the two-hop range of the initially elected leader node, there are nodes whose nodes within two hops have entered other clusters: when the initially elected leader node shakes hands with the nodes within two hops, if the node has entered other two-hop network formations, the node returns a request return message when it receives the request to join the network message again; at this time, the initially elected leader node marks the node within two hops of the leader node, and the node marks itself as an interconnected node, and at the same time announces it to the cluster leader where the node is located. The nodes marked as interconnected nodes will become candidates for gateway nodes.

[0012] Furthermore, the leader node allocates time slots to the nodes within the preset range of the leader node, and at the same time constructs a time slot allocation table, including: The leader node shakes hands with the nodes within two hops of the leader node in sequence and pre-allocates time slots; when there is no conflict in time slot allocation, the node allocated the time slot at this time occupies the time slot; if the allocated time slot conflicts with the time slot allocated to the nodes in other two-hop clusters, the node allocated the time slot returns a conflict message at this time, and the leader node re-allocates the time slot for the node until all the nodes within two hops are allocated; after accessing all the nodes, each node constructs a time slot allocation table.

[0013] Furthermore, the leader node recommends gateway nodes according to the neighbor node information table, including: The leader node calculates the gateway recommendation degree of each node according to the neighbor node information table, and recommends gateway nodes according to the gateway recommendation degree; When recommending a gateway, it is divided into the following three situations: First, there is no interconnected node: if there is no interconnected node at this time, the leader node selects the two-hop nodes under its jurisdiction to become candidate gateways, and calculates the gateway recommendation degrees of all the two-hop nodes under the leader node respectively, and selects the node with the highest recommendation degree to become the gateway node; if there are no two-hop nodes, the nodes within one hop of the leader node become candidate gateways; Second, there is only one interconnected node: when there is only one interconnected node, then recommend this interconnected node to become the gateway node; Third, there are multiple interconnected nodes: the leader node selects all interconnected nodes as candidate gateways, calculates the gateway recommendation degrees of the candidate gateways respectively, and recommends the candidate gateway with the highest gateway recommendation degree to become the gateway node; Among them, the average signal strength of the candidate node with the leader node and the two-hop nodes is used as the gateway recommendation degree, and the specific formula is as follows:

[0014] In the formula, is the average signal strength of the i-th node in the j-th two-hop cluster, is the set of the leader node and all two-hop nodes in the j-th two-hop cluster range, is the number of all candidate gateway nodes in the j-th two-hop cluster; is the candidate gateway node and any node among the leader node or two-hop nodes the wireless received signal strength therebetween.

[0015] Furthermore, it further includes: during the data communication of each node, if a new node joins the network and an existing networked node exits the two-hop cluster range, the new node or the existing networked node keeps silent listening, joins the network during the contention access time slot or exits the two-hop cluster range, and at the same time re-allocates a time slot.

[0016] Furthermore, the initialization of the initially networked nodes and the neighbor node information table in the network model includes: each node broadcasts an information message in sequence according to the order of the access ID at this time; the nodes in the network model maintain the neighbor node information table according to the message information; save the received signal strength, absolute position, and mobility of the neighbor nodes in the neighbor node information table, and at the same time update and save the neighbor node information in the one-hop information table in the message in the neighbor node information table, and mark that neighbor node as a two-hop neighbor node obtained by this one-hop node.

[0017] A hybrid time slot allocation system applicable to high-dynamic network clustering management includes: a model construction module, configured to construct a network model based on the situation information of each node in a high-dynamic network, and at the same time initialize the initially networked nodes and the neighbor node information table in the network model; wherein each node in the high-dynamic network adopts a clustering design; a leader node election module, configured to elect a leader node based on the weight values of each node calculated according to the neighbor node information table; a time slot allocation module, configured to allocate time slots to the nodes within the preset range of the leader node by the leader node, and at the same time construct a time slot allocation table; a recommendation module, configured to recommend a gateway node by the leader node according to the neighbor node information table to realize initial networking; the gateway node is used for communicating with the remaining preset range clusters outside in the gateway communication frequency band; a data communication module, configured to perform data communication of each node in the network model according to the time slot allocation table after the initial networking is successful.

[0018] Compared with the prior art, the present invention has the following beneficial effects: The present invention provides a hybrid time slot allocation method applicable to high-dynamic network clustering management. By converting the research of traditional flat networks to hierarchical networks, all nodes in the network are clustered, thereby reducing the collision rate within two hops. Neighbor information is broadcast in the hierarchical network. According to the neighbor information, each node obtains a weight value, and after obtaining the weight value, the node with the highest weight value within a preset range is used as the leader node, and a cluster subnet is constructed with the leader node as the core. Through the election of the leader node, the maintenance time of the cluster subnet can be prolonged, and at the same time, since all nodes within the preset range are uniformly managed by the leader node, collisions between nodes can be effectively avoided. When extended to the entire network, the collision rate is greatly reduced, the throughput is improved, and the requirements for dynamic expansion and high system throughput are met.

[0019] In addition, to address the problem of the sharp increase in control overhead caused by the expansion of the node scale in current designs, this method adopts a hierarchical network architecture and a node dynamic network access design. With the hierarchical network architecture, the leader node uniformly allocates time slots initially. Even when the scale expands, there is no need to repeatedly negotiate time slots in one round, and the jurisdiction of the leader node can greatly reduce the control overhead during the data interaction phase. At the same time, due to the adoption of the node dynamic network access design, when a node self-checks and finds that it has left the network, it will re-enter the network autonomously after listening, avoiding the problem of having to broadcast control frames when entering the network midway, reducing the conflicts generated between nodes due to network access, and ensuring the quality of service within the cluster while maintaining the network topology. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 is the network model provided by an embodiment of the present invention; Figure 2 is the schematic diagram of the initial network topology provided by an embodiment of the present invention; Figure 3 is the schematic diagram of the frame structure provided by an embodiment of the present invention; Figure 4 is the schematic diagram of node information message interaction provided by an embodiment of the present invention; Figure 5 is the schematic diagram of a new node accessing the network provided by an embodiment of the present invention; Figure 6 is the flowchart of the hybrid time slot allocation method applicable to high-dynamic network clustering management provided by an embodiment of the present invention; Figure 7 is the flowchart of a hybrid time slot allocation method applicable to high-dynamic network clustering management provided by the present invention; Figure 8 is the schematic diagram of the structure of a hybrid time slot allocation system applicable to high-dynamic network clustering management provided by the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0021] To further understand the content of the present invention, the present invention will be described in detail below in conjunction with the accompanying drawings and specific embodiments. It should be understood that the embodiments are only for explaining the present invention and not for limiting it.

[0022] As described in the background art, currently, the time slot allocation of the dynamic allocation algorithm depends on the negotiation between nodes. In a high-dynamic environment, as the scale of nodes increases, the collision rate of the dynamic allocation algorithm will increase significantly, which will instead lead to a decrease in system throughput. With the sinking of network devices and the decline in costs, the scale of various networks in real life is also increasing day by day. The current design is difficult to meet the scalability of nodes in the network, and the designed idea is not applicable to the scenario of dynamic expansion of the network scale. Moreover, due to the lack of consideration of the impact of control overhead on the system, it is also difficult to meet the demand for high system throughput.

[0023] Embodiment 1 To solve the above problems, this embodiment provides a hybrid time slot allocation method applicable to high-dynamic network clustering management. This method realizes fast network formation by establishing clusters within two hops, achieving collision-free communication within two hops of the cluster leader; realizes fast network formation of new nodes and isolated nodes through dynamic information perception of nodes; and realizes dynamic maintenance of the network topology and real-time update of the network topology by periodically broadcasting control messages, ensuring real-time dynamic perception of the nodes in the network. This allocation method can achieve conflict-free transmission within two hops through the cluster method, and improve the network throughput through time slot multiplexing outside two hops.

[0024] This embodiment provides a hybrid time slot allocation method applicable to high-dynamic network clustering management, including: Constructing a network model based on the situation information of each node in the high-dynamic network, and initializing the nodes in the initial network formation and the neighbor node information table in the network model; wherein each node in the high-dynamic network adopts a clustering design; Selecting the leader node through competition based on the weight values of each node calculated from the neighbor node information table; The leader node allocates time slots to the nodes within the preset range of the leader node, and constructs a time slot allocation table at the same time; The leader node recommends a gateway node according to the neighbor node information table to realize initial network formation; the gateway node is used to communicate with other preset range clusters outside the gateway in the gateway communication frequency band; After the initial network formation is successful, data communication of each node in the network model is carried out according to the time slot allocation table.

[0025] The following further explains the design method provided in this embodiment in conjunction with the accompanying drawings: As Figure 6As shown in the figure, this embodiment provides a hybrid time slot allocation method applicable to high-dynamic network clustering management, which is specifically as follows: Step 1: According to the situation information of each node in the high-dynamic network, construct a hierarchical network model, divide the communication frequency band at the same time, and determine the communication frame structure.

[0026] As Figure 1 shown, the constructed network model is: all nodes in the network have transceiver functions, but cannot transmit and receive simultaneously; each node negotiates and exchanges information with the rest of the nodes, completes time slot allocation according to dynamic information perception, accesses channel resources in the corresponding time slots, and completes data transmission and reception. There are nodes of different levels in the network, including cluster leader nodes, gateway nodes, and ordinary nodes, and the network model. The cluster leader node is responsible for managing the initial time slot allocation of the cluster and the election of gateway nodes; the gateway node is responsible for communicating with other clusters; the ordinary node is the basic component of the cluster and is responsible for generating and processing data.

[0027] The communication frequency band is divided into two frequency bands: cluster communication frequency band and gateway communication frequency band. If all nodes within two-hop clusters need to communicate within the cluster, they all communicate in the cluster communication frequency band. If there is a need for a node in this two-hop cluster to communicate with a node in an external two-hop cluster, the elected gateway node will communicate in the gateway communication frequency band.

[0028] The communication frame structure mainly includes five stages in the embodiment: synchronization stage, control stage, fixed time slot allocation stage, reserved time slot allocation stage, and isolated node competition stage. In the synchronization stage, each node receives a synchronization signal, and at this time all nodes complete clock synchronization. The control stage is mainly responsible for the construction and maintenance of the network topology. The control stage is divided into 3 sub-frames, namely information sub-frame, leader election sub-frame, and gateway election sub-frame. The information sub-frame is the time frame for global information interaction, which consists of K time slots, and the number of K is the maximum number of nodes in the task cluster. The leader election sub-frame uses a comparison method to elect the leader within two hops, and the gateway election sub-frame is directly elected by the elected cluster leader according to the election degree of candidate gateways. The fixed time slot allocation nodes and the reserved time slot allocation stage are used for collision-free data interaction between nodes, which consists of N fixed time slots and M reserved time slots. Where N is the maximum number of nodes in each two-hop cluster, and M is the reserved time slot, and its value is related to the value of N. The isolated node competition stage is used for the rapid access of isolated nodes.

[0029] Step 2: According to the network model constructed in Step 1, initialize the nodes in the initial network according to the communication frame structure and the message structure. During the initialization, control messages are broadcast to complete the initialization of the neighbor node information table; When the initial topology of each node in the network is established, each node is in an isolated state. At this time, each node broadcasts information packets in sequence according to the order of the network access ID. Nodes in the network will maintain a neighbor node information table based on the packet information. In the neighbor node information table, the received signal strength, absolute position, and mobility of neighbor nodes are saved into the neighbor information table. At the same time, the neighbor node information in the one-hop information table in the packet is updated and saved into the neighbor node information table, and it is marked as a two-hop neighbor node obtained from this one-hop node.

[0030] Step 3: Each node calculates its own weight value based on the data in the neighbor node information table, broadcasts and competes for the leader node. The node elected as the leader shakes hands with the nodes within its two-hop range in sequence and pre-allocates time slots. When there is no conflict in the allocated time slots, the nodes allocated with time slots at this time occupy the time slots; if the allocated time slots conflict with the time slots allocated to the nodes in the rest of the two-hop clusters, the nodes allocated with time slots at this time return conflict packets, and the leader node re-allocates time slots for this node. After accessing all nodes, each node constructs a time slot allocation table.

[0031] The election of the cluster leader needs to consider factors such as the stability degree and signal strength of the nodes in order to better ensure the stability of the cluster. In this embodiment, the node degree, link survival time, average node distance, remaining energy, and load degree are used as input variables.

[0032] Node degree: The node degree includes the number of 1-hop and 2-hop nodes detected by the node. The calculation of its node degree is as follows:

[0033] In the formula, represents the node degree of the node with ID i, which is a normalized value. and respectively represent the number of 1-hop and 2-hop nodes of the i-th node. represents the maximum value of the node degree before normalization in this cluster. Assume that the maximum number of nodes in each two-hop cluster is , then the highest node degree situation is all nodes are within the 1-hop range of this node, then the node degree value at this time is , which is the maximum value of the node degree.

[0034] Link survival time: For nodes with two hops as a cluster, the cluster leader needs to have a long survival time and small fluctuations in the link. This value can represent the stability degree of a stable cluster. Since each node is located in a three-dimensional space, three-dimensional coordinates are needed to mark the mobility of the nodes. The following vector is used to represent the speed and the direction of movement. Convert into polar coordinate form:

[0035] Let represent the link survival time between node and node . represent the three - dimensional coordinates of the \(i\)-th node . represent the three - dimensional coordinates of node . represent 's mobility, represent 's mobility, then it satisfies:

[0036] wherein, represents the communication radius covered by node \(i\), , , respectively represent the distance factors of the \(x\), \(y\), and \(z\) axes affecting :

[0037]

[0038]

[0039] Through the above formula, the link survival time between node and node can be obtained. Calculate and average the link survival times of all nodes within the two - hop range of node , then we can get:

[0040] Normalize it, and at this time we can get:

[0041] wherein, represents the average link survival time after normalization, represents the interval for regular update of control messages. If the average link survival time is greater than this value, it means that the link remains stable during this control message update cycle.

[0042] Average node distance: Taking the node as the center, the average distance between it and all nodes within its two - hop range is the average node distance. If the average distance is lower, it means that the structure of the two - hop cluster is more compact and the connection is more stable. Its average distance calculation formula is as follows:

[0043] In the formula, represents the average distance between the $i$-th node and all nodes within its two-hop range, is the set of all nodes except the node itself within the $j$-th two-hop cluster range, represents the number of the set of all nodes except the node itself within the two-hop cluster range, represents the $i$-th node to node The Euclidean distance is calculated as follows:

[0044] In the formula, represents the three-dimensional coordinates of the $i$-th node and represents the three-dimensional coordinates of node .

[0045] Normalize the average node distance, and then we get:

[0046] In the formula, represents the normalized average node distance, represents the maximum two-hop transmission distance of the node, represents the minimum two-hop transmission distance of the node.

[0047] Remaining energy: The remaining energy of the node determines its remaining survival time. The longer the survival time, the higher the link stability and the longer the survival time of the cluster. The remaining energy of the node is calculated as follows:

[0048] In the formula, represents the normalized value of the remaining energy of the $i$-th node, , respectively represent the maximum energy and the minimum energy in the cluster, represents the current actual energy of the $i$-th node. The larger this value is, the more remaining energy there is Load degree: The remaining load tasks of the node other than maintaining the cluster. The more load the node has, the greater the energy consumption, the shorter the survival time, and the lower the stability of the cluster. The load can be represented by the current energy consumption, and the normalized load degree can be expressed as:

[0049] In the formula, represents the normalized load degree, Represents the maximum load of the node, Represents the load consumption of the i-th node at the current moment.

[0050] At this time, its weight value is calculated as follows:

[0051] In the formula, Represents the degree of the node with ID i, Represents the normalized average link survival time, Represents the normalized average node distance, Represents the normalized value of the remaining energy of the i-th node, Represents the normalized load degree, 、 、 、 、 Respectively represent the weights corresponding to each parameter. Then the weight value of the node with ID i is 。

[0052] After each node obtains its own weight, then each node broadcasts the weight message in sequence according to the node ID. After broadcasting the weights in sequence, the node with the largest weight value in the one-hop range becomes the initially elected leader node.

[0053] If there is only the initially elected cluster leader node as the cluster leader within the two-hop range of the current cluster leader, then at this time, this cluster leader node shakes hands with each two-hop node in sequence according to the order of its two-hop neighbor table. The leader node within two hops sends a request for network access message carrying the allocated time slot to request the node to access the network. The node that receives the request for network access message, if it detects no collision, returns a request return message and broadcasts the allocated time slot within its one-hop range. Conversely, if it detects that the time slot allocated by the leader has been occupied by other nodes, then at this time it returns a collision message, and the leader node reallocates the nodes after obtaining the time slot message. And so on, after all handshakes are successful, the leader node officially becomes the cluster leader in the cluster within the two-hop range, and the remaining nodes become ordinary cluster units under the jurisdiction of this leader node within the two-hop range. Before the next regular update of the control message, each node needs to maintain its time slot allocation, but when a collision occurs, at this time each node needs to adjust itself.

[0054] There are other nodes that have become cluster leaders within two hops. If there are other cluster leaders within the two-hop range outside the one-hop range of the currently initially elected leader node, then a comparison needs to be made at the handshake moment, and the node with the larger weight value is selected as the only cluster leader within the two-hop range, while the other cluster leader node with the smaller weight value merges into the cluster leader node with the larger weight value. The cluster leader with the smaller weight value broadcasts a cluster dissolution message to the nodes that have been confirmed to be networked within its two-hop range, and the nodes that receive the cluster dissolution message become isolated nodes waiting for handshake or competition.

[0055] There are non-leader nodes that have entered other clusters within two hops. Within the two-hop range of the initially elected leader node, it is also possible that there are nodes whose inner nodes within two hops have entered other clusters. When the initially elected leader conducts a handshake with the nodes within two hops, if the node has entered the other two-hop network, the node returns a request return message when it receives the request to join the network again. At this time, the leader node marks the node within its two-hop range, and the node needs to mark itself as an interconnected node and announce it to the cluster leader it belongs to. The nodes marked as interconnected nodes will become candidates for gateway nodes.

[0056] Step 4: After the initial time slots of all nodes are allocated, the leader node calculates the gateway nomination degrees of all nodes based on the neighbor node information table, and then nominates the gateway node. The gateway node is responsible for communicating with the other two-hop clusters outside in the gateway communication frequency band.

[0057] The gateway node needs to meet the requirements of communicating with external clusters and ensure the effectiveness of inter-cluster communication. When nominating the gateway, the following three situations are involved: 1) No interconnected node: If there is no interconnected node at this time, the leader node selects the two-hop nodes under its jurisdiction as candidate gateways, calculates the gateway nomination degrees of all the two-hop nodes under its jurisdiction respectively, and selects the node with the highest nomination degree as the gateway. If there are no two-hop nodes, then the one-hop nodes become candidate gateways; 2) There is exactly one interconnected node: When there is only one collision-prone node, it is directly nominated as the gateway at this time; 3) There are multiple interconnected nodes: The leader node selects all the collision-prone nodes as candidate gateways, calculates the gateway nomination degrees of the candidate gateways respectively, and nominates the candidate gateway corresponding to the highest gateway nomination degree.

[0058] Since the information to be sent by the nodes is mainly sorted out by the leader node, and at the same time, the gateway node needs to communicate with the other two-hop clusters, and its external communication range has extended beyond two hops of the cluster, it is necessary to ensure that the gateway node can maintain good signal strength with both the leader node and at least the nodes two hops outside the cluster. Therefore, considering comprehensively, when electing the gateway, calculate the average signal strength of the candidate node with the leader node and the two-hop nodes as the gateway election degree of the candidate node:

[0059] In the formula, is the average signal strength of the i-th node in the j-th two-hop cluster, is the set of the leader node and all two-hop nodes in the range of the j-th two-hop cluster, is the number of all candidate gateway nodes in the j-th two-hop cluster. is the candidate gateway node and any node among the leader node or the two-hop nodes the wireless received signal strength between them.

[0060] The leader node elects the gateway according to the election degree of the candidate gateway node, and broadcasts it globally after the election.

[0061] Step Five: After the initial network formation is successful, each node realizes collision-free data communication according to the time slot allocation table in Step Three. During the process of node communication and movement, if a new node joins the network and an existing networked node exits the two-hop cluster range, then the node remains silent and listens to enter the network during the contention access time slot, and re-allocates the time slot.

[0062] In the face of two situations: a new node joins the network and a cluster node itself moves out of the two-hop range of the original cluster leader, both will cause the node to become an isolated node and need to quickly join the network. For the above situations, a contention access time slot is fixed in the time slot. At the same time, to avoid collisions, for a new node or such a node that senses itself becoming an isolated node, it keeps listening to the information within one-hop range, then determines the time slot it pre-applies for, competes during the subsequent contention access time slot, and waits for the confirmation of the neighbor node. After successful confirmation, it joins the network. If a conflict or collision occurs, it keeps listening and contends again after a backoff period.

[0063] Step Six: After the node completes multiple data interactions, it periodically updates the network topology and maintains the network formation, and then enters the next cycle.

[0064] In this embodiment, it is applied to a high-dynamic environment where the positions of the nodes are always changing. After establishing a stable cluster network, control information is broadcast at regular intervals. Each node broadcasts the control information in sequence according to its ID, updates the network topology again, and maintains the stability and reliability of the network structure.

[0065] The specific example operation of the dynamic time slot allocation method provided in this embodiment is as follows: As Figure 2 In the network shown, in step one, according to the situation information of each node in the high-dynamic network, a hierarchical network model is constructed, the cluster communication frequency band and the gateway communication frequency band are divided, and the communication frame structure is determined. In this example, it is assumed that the cluster communication frequency band and the gateway frequency band have been divided, and the cluster communication frequency band and the gateway frequency band are orthogonal to each other and do not interfere with each other. It is assumed that the maximum number of nodes in a two-hop cluster is N = 8, the reserved time slots are M = 3, and the total number of nodes in the current task cluster is defined as K = 16. The specific time frame structure is as Figure 3 shown.

[0066] As Figure 4 shown, in step two, for the already constructed network model, initialization operations are performed at this time to construct a neighbor node information table. In the SYN time slot, nodes A to J in the figure complete a clock synchronization. In the INF1 to INF K time slots in the INF stage of the CTL sub-frame, nodes A to J broadcast INF messages in sequence. At this time, each node can obtain its one-hop nodes and some two-hop nodes routed by the one-hop nodes.

[0067] In step three, when all the INF messages are broadcast, each node synchronously calculates its weight value (the weight value is divided into 7 levels). In the subsequent ECH stage, each node broadcasts the WIG message in sequence according to the order of the book, and broadcasts the obtained weight value table to the nodes within its one-hop range. In this example, the weight is calculated by comprehensively combining the load degree, remaining energy, link survival time, node degree, and average distance. After the broadcast, each node will obtain the weight values of all nodes and the weight values of some nodes within two hops. After the weight calculation, after this broadcast, node A will become the maximum weight within its two-hop range. Except for node A's two hops, the maximum weight within two hops of nodes B, H, and J is node E, and the node with the maximum weight within two hops of node C will be node J. Obviously, initially, nodes D, E, F, G, and I will wait for node A's handshake, nodes B, H, and J will wait for node E's handshake, and node C will wait for node J's handshake.

[0068] During the handshake process of node A, node A shakes hands in sequence according to the ID numbers within one hop and the ID numbers within two hops. When allocating its one-hop nodes, since node A has the maximum weight within one hop, it can be directly allocated. The time slot tables allocated by the A cluster are shown in Table 1: Table 1 Time Slot Allocation Table of Node A

[0069] When Node A shakes hands with Node E, Node E will broadcast a RET message, and its one-hop neighbors will detect this information. At this time, its one-hop nodes will set the weight of Node E to 0 and re-elect the initial node. For Node H, since it has no cluster to enter (the two-hop path to J that is not networked is blocked by E), therefore, after Node H detects that Node E has reserved the 4th time slot, it directly applies for the 5th time slot dynamically. At this time, since the 5th time slot in Node A is allocated to Node G and there is no conflict with Node E and its one-hop neighbor nodes, therefore, Node H successfully reserves the 5th time slot at this time.

[0070] For Nodes B, C, and J, after detecting that Node E has broadcast that it has reserved the 4th time slot, Node J becomes the cluster leader of Nodes B, C, and J. Subsequently, Node J shakes hands with Node B, then with Node C, and finally allocates the 3rd time slot to itself. The time slot allocation of Node J is as shown in Table 2: Table 2 Time Slot Allocation Table of Node J

[0071] At this time, the networking of the nodes is completed, and each node has achieved conflict-free time slot transmission.

[0072] In Step 4, according to the nodes in each cluster, there is only Node E as the interconnected node in Cluster A, so Node E is elected as the gateway node. In Cluster J, only Node C meets the requirements, and Node C becomes the gateway node. Node H is an isolated node. Although it can achieve conflict-free time slot allocation, there is only itself as a node in Cluster H, so Node H becomes the gateway.

[0073] As Figure 5 shown, in Step 5, assume that Node K needs to quickly join the network at this time. After Node K enters the network, it cannot apply first because it is impossible to determine the time slot to apply for at this time. First, it listens. According to the above time slot allocation situation, the allocated time slots obtained by Node K in one round of listening are as follows: Table 3 Time Slot Allocation Table of Node K

[0074] According to the above listening, at this time, Node K preferentially applies for the 2nd time slot in the fixed time slots to become the occupied time slot. In the APP time slot, it broadcasts an APP message to its one-hop to apply for the 2nd time slot to become the broadcast time slot. After its one-hop time slot detects the application broadcast, it checks that there are no neighbor nodes receiving or sending in the 2nd time slot. Therefore, Node K successfully obtains this time slot, and the rapid conflict-free network entry of Node K ends.

[0075] In step six, when reaching the time slot for the timing broadcast control message, perform network-wide synchronization, and simultaneously perform information message interaction, leader re-election, and network topology maintenance; that is, repeat step two and step five.

[0076] Embodiment 2 As Figure 7 shown, this embodiment provides a hybrid time slot allocation method applicable to high-dynamic network clustering management, including the following steps: Construct a network model based on the situation information of each node in the high-dynamic network, and simultaneously initialize the nodes in the initial network formation and the neighbor node information table in the network model; where each node in the high-dynamic network adopts a clustering design; Based on the weight values of each node calculated from the neighbor node information table, elect a leader node through a competition; The leader node allocates time slots to the nodes within the preset range of the leader node, and simultaneously constructs a time slot allocation table; The leader node recommends a gateway node based on the neighbor node information table to achieve initial network formation; the gateway node is used to communicate with the rest of the preset range clusters outside in the gateway communication frequency band; After the initial network formation is successful, perform data communication for each node in the network model according to the time slot allocation table.

[0077] Among them, the constructing a network model based on the situation information of each node in the high-dynamic network and simultaneously initializing the nodes in the initial network formation and the neighbor node information table in the network model includes: Construct a network model based on the situation information of each node in the high-dynamic network, and simultaneously divide the communication frequency band to obtain a communication frame structure; Based on the constructed network model, combined with the communication frame structure and the preset message structure, initialize the nodes in the initial network formation and the neighbor node information table; and simultaneously initialize the neighbor node information table by broadcasting control messages.

[0078] In this embodiment, the communication frequency band is divided into two frequency bands: the cluster communication frequency band and the gateway communication frequency band; among them, all nodes within two-hop clusters communicate in the cluster communication frequency band if they communicate within the cluster; if there is a need for communication between nodes in this two-hop cluster and nodes in external two-hop clusters, the recommended gateway node communicates in the gateway communication frequency band; The design process of the communication frame structure includes: a synchronization phase, a control phase, a fixed time slot allocation phase, a reserved time slot allocation phase, and an isolated node competition phase; The synchronization phase is used to enable all nodes to complete clock synchronization; The control phase is used for the formation and maintenance of the network topology; The fixed time slot allocation phase and the reserved time slot allocation phase are jointly used for collision-free data interaction between nodes; The isolated node competition phase is used for the rapid network access of isolated nodes.

[0079] Specifically, the weight values of the nodes are calculated based on the node degree, link survival time, average node distance, remaining energy, and load degree in the neighbor node information table. The specific formula is as follows:

[0080] In the formula, represents the node degree of the node with ID i, represents the normalized average link survival time, represents the normalized average node distance, represents the value of the remaining energy of the i-th node after normalization, represents the normalized load degree, , , , , respectively represent the weights corresponding to the parameters; then the weight value of the node with ID i is .

[0081] Here, the specific steps for the election of the leader node are as follows: Each node broadcasts its weight value in turn according to the node ID; after broadcasting the weight values in turn, the node with the largest weight value in the one-hop range is elected as the initially recommended leader node; If within the two-hop range of the initially recommended leader node: there is only one cluster leader, which is the initially recommended leader node, then the initially recommended leader node shakes hands with each two-hop node in turn according to the order of its two-hop neighbor node information table; the initially recommended leader node sends a request for network access message carrying the allocated time slot to request the node to access the network; for the node that receives the request for network access message, if it detects no collision, it returns a request return message and broadcasts the allocated time slot of this node within the one-hop range of this node; if it detects that the time slot allocated by the initially recommended leader node has been occupied by other nodes, it returns a collision message; the initially recommended leader node reallocates the nodes according to the collision message; after all handshakes are successful, the initially recommended leader node becomes the cluster leader in the two-hop range cluster, and the remaining nodes become ordinary cluster units under the jurisdiction of the cluster leader within the two-hop range; and before the next regular update of the control message, each node maintains its own time slot allocation; when a collision occurs, each node adjusts itself; There are other nodes that have become cluster leaders within two hops: If there are other cluster leaders within the two-hop range outside the one-hop range of the currently initially elected leader node, a comparison is made at the handshake moment: The node with the larger weight value is selected as the only cluster leader within the two-hop range, and the other cluster leader with the smaller weight value is merged into the cluster leader with the larger weight value. The cluster leader with the smaller weight value broadcasts a cluster dissolution message to the nodes that have been confirmed to be networked within its two-hop range. The nodes that receive the cluster dissolution message become isolated nodes and wait for a handshake or to compete; There are non-leader nodes that have entered other clusters within two hops: Within the two-hop range of the initially elected leader node, there are nodes whose nodes within two hops have entered other clusters: When the initially elected leader node conducts a handshake with the nodes within two hops, if the node has entered other two-hop networkings, the node returns a request return message when it receives the request to join the network again; At this time, the initially elected leader node marks the node within two hops of the leader node, and the node marks itself as an interconnected node and simultaneously announces it to the cluster leader where the node is located. The nodes marked as interconnected nodes will become candidates for gateway nodes.

[0082] Specifically, the leader node allocates time slots to the nodes within the preset range of the leader node, and simultaneously constructs a time slot allocation table, including: The leader node sequentially conducts handshakes with the nodes within two hops of the leader node and pre-allocates time slots; When the allocated time slots have no conflicts, the nodes allocated time slots at this time occupy the time slots; If the allocated time slots conflict with the time slots allocated to the nodes in other two-hop clusters, the nodes allocated time slots at this time return a conflict message, and the leader node re-allocates time slots to the node according to the conflict message until all the nodes within the two-hop range are allocated; After accessing all the nodes, each node constructs a time slot allocation table.

[0083] Here, the leader node recommends gateway nodes according to the neighbor node information table, including: The leader node calculates the gateway recommendation degrees of each node according to the neighbor node information table, and recommends gateway nodes according to the gateway recommendation degrees; When recommending a gateway, it is divided into the following three situations: First, there is no interconnected node: If there is no interconnected node at this time, the leader node selects the two-hop nodes under its jurisdiction as candidate gateways, and calculates the gateway recommendation degrees of all the two-hop nodes under the leader node respectively, and selects the node with the highest recommendation degree as the gateway node; If there are no two-hop nodes, the nodes within one hop of the leader node become candidate gateways; Second, there is exactly one interconnected node: When there is exactly one interconnected node, then recommend the interconnected node as the gateway node; Thirdly, there are multiple interconnected nodes: the leader node selects all interconnected nodes as candidate gateways, calculates the gateway recommendation degrees of the candidate gateways respectively, and recommends the candidate gateway with the highest gateway recommendation degree as the gateway node; Among them, the average signal strength between the candidate node, the leader node and the two-hop nodes is used as the gateway recommendation degree, and the specific formula is as follows:

[0084] In the formula, is the average signal strength of the i-th node in the j-th two-hop cluster, is the set of the leader node and all two-hop nodes in the range of the j-th two-hop cluster, is the number of all candidate gateway nodes in the j-th two-hop cluster; is the candidate gateway node and any node among the leader node or the two-hop nodes the wireless received signal strength between them.

[0085] The allocation method provided in this embodiment further includes: during the data communication process of each node, if a new node joins the network and an existing networked node exits the two-hop cluster range, the new node or the existing networked node keeps silent listening, joins the network during the competition access time slot or exits the two-hop cluster range, and at the same time re-allocates the time slot.

[0086] In this embodiment, the initialization of the initial networked nodes and the neighbor node information table in the network model includes: At this time, each node broadcasts information packets in sequence according to the order of the access ID; The nodes in the network model maintain the neighbor node information table according to the packet information; Save the received signal strength, absolute position and mobility of the neighbor node in the neighbor node information table. At the same time, update and save the neighbor node information in the one-hop information table in the packet in the neighbor node information table, and mark that the neighbor node is the two-hop neighbor node obtained by this one-hop node.

[0087] Such as Figure 8As shown in the figure, this embodiment also provides a hybrid time slot allocation system applicable to high-dynamic network clustering management, including: a model construction module, which is used to construct a network model based on the situation information of each node in the high-dynamic network, and at the same time initialize the nodes in the initial network formation in the network model and the neighbor node information table; where each node in the high-dynamic network adopts a clustering design; a leader node election module, which is used to elect a leader node based on the weight values of each node calculated from the neighbor node information table; a time slot allocation module, which is used for the leader node to allocate time slots to the nodes within the preset range of the leader node, and at the same time construct a time slot allocation table; a recommendation module, which is used for the leader node to recommend a gateway node according to the neighbor node information table to achieve initial network formation; the gateway node is used to communicate with the other preset range clusters outside in the gateway communication frequency band; a data communication module, which is used to perform data communication between each node in the network model according to the time slot allocation table after the initial network formation is successful.

[0088] The present invention also provides a device, including: a memory, which is used to store a computer program; a processor, which is used to implement the steps of the above-mentioned hybrid time slot allocation method applicable to high-dynamic network clustering management when executing the computer program.

[0089] When the processor executes the computer program, it implements the steps of the above-mentioned hybrid time slot allocation applicable to high-dynamic network clustering management, for example: constructing a network model based on the situation information of each node in the high-dynamic network, and at the same time initializing the nodes in the initial network formation in the network model and the neighbor node information table; where each node in the high-dynamic network adopts a clustering design; electing a leader node based on the weight values of each node calculated from the neighbor node information table; the leader node allocates time slots to the nodes within the preset range of the leader node, and at the same time constructs a time slot allocation table; the leader node recommends a gateway node according to the neighbor node information table to achieve initial network formation; the gateway node is used to communicate with the other preset range clusters outside in the gateway communication frequency band; after the initial network formation is successful, perform data communication between each node in the network model according to the time slot allocation table.

[0090] Alternatively, when the processor executes the computer program, it implements the functions of each module in the above system. For example: The model construction module is used to construct a network model based on the situation information of each node in the high-dynamic network, and at the same time initialize the nodes of the initial network formation in the network model and the neighbor node information table; wherein each node in the high-dynamic network adopts a clustering design; The leader node election module is used to elect a leader node based on the weight values of each node calculated from the neighbor node information table; The time slot allocation module is used for the leader node to allocate time slots to the nodes within the preset range of the leader node, and at the same time construct a time slot allocation table; The recommendation module is used for the leader node to recommend a gateway node according to the neighbor node information table to achieve the initial network formation; The gateway node is used to communicate with the other preset range clusters outside in the gateway communication frequency band; The data communication module is used to perform data communication of each node in the network model according to the time slot allocation table after the initial network formation is successful.

[0091] Exemplarily, the computer program can be divided into one or more modules / units, and the one or more modules / units are stored in the memory and executed by the processor to complete the present invention. The one or more modules / units can be a series of computer program instruction segments capable of completing preset functions, and the instruction segments are used to describe the execution process of the computer program in the hybrid time slot allocation device applicable to high-dynamic network clustering management. For example, the computer program can be divided into a model construction module, a leader node election module, a time slot allocation module, and a recommendation module; the specific functions of each module are as follows: The model construction module is used to construct a network model based on the situation information of each node in the high-dynamic network, and at the same time initialize the nodes of the initial network formation in the network model and the neighbor node information table; wherein each node in the high-dynamic network adopts a clustering design; The leader node election module is used to elect a leader node based on the weight values of each node calculated from the neighbor node information table; The time slot allocation module is used for the leader node to allocate time slots to the nodes within the preset range of the leader node, and at the same time construct a time slot allocation table; The recommendation module is used for the leader node to recommend a gateway node according to the neighbor node information table to achieve the initial network formation; The gateway node is used to communicate with the other preset range clusters outside in the gateway communication frequency band; The data communication module is used to perform data communication of each node in the network model according to the time slot allocation table after the initial network formation is successful.

[0092] The hybrid time slot allocation device applicable to high-dynamic network clustering management may be a computing device such as a desktop computer, a notebook, a palm computer, and a cloud server. The hybrid time slot allocation device applicable to high-dynamic network clustering management may include, but is not limited to, a processor and a memory. Those skilled in the art can understand that the above are examples of the hybrid time slot allocation device applicable to high-dynamic network clustering management, and do not constitute a limitation on the hybrid time slot allocation device applicable to high-dynamic network clustering management. It may include more components than the above, or combine certain components, or different components. For example, the hybrid time slot allocation device applicable to high-dynamic network clustering management may further include input / output devices, network access devices, a bus, etc.

[0093] The so-called processor may be a central processing unit (CPU), or may also be other general-purpose processors, digital signal processors (DSPs), application specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. The general-purpose processor may be a microprocessor, or the processor may also be any conventional processor, etc. The processor is the control center of the hybrid time slot allocation applicable to high-dynamic network clustering management, and connects various parts of the entire hybrid time slot allocation device applicable to high-dynamic network clustering management through various interfaces and lines.

[0094] The memory can be used to store the computer programs and / or modules. The processor realizes various functions of the hybrid time slot allocation device applicable to high-dynamic network clustering management by running or executing the computer programs and / or modules stored in the memory, and by calling the data stored in the memory.

[0095] The memory may mainly include a program storage area and a data storage area. Among them, the program storage area may store an operating system, application programs required for at least one function (such as a sound playback function, an image playback function, etc.); the data storage area may store data created according to the use of the mobile phone (such as audio data, phone book, etc.). In addition, the memory may include a high-speed random access memory, and may also include a non-volatile memory, such as a hard disk, a memory, a plug-in hard disk, a smart media card (SMC), a secure digital (SD) card, a flash card, at least one magnetic disk storage device, a flash memory device, or other volatile solid-state storage devices.

[0096] The present invention also provides a computer-readable storage medium storing a computer program, and when the computer program is executed by a processor, the steps of the hybrid time slot allocation method applicable to high-dynamic network clustering management are implemented.

[0097] If the modules / units integrated in the hybrid time slot allocation system applicable to high-dynamic network clustering management are implemented in the form of software functional units and sold or used as independent products, they can be stored in a computer-readable storage medium.

[0098] Based on such an understanding, all or part of the processes in the hybrid time slot allocation method applicable to high-dynamic network clustering management of the present invention can also be completed by instructing relevant hardware through a computer program. The computer program can be stored in a computer-readable storage medium. When the computer program is executed by a processor, the steps of the hybrid time slot allocation method applicable to high-dynamic network clustering management can be implemented. Among them, the computer program includes computer program code, and the computer program code can be in the form of source code, object code, executable file, or a preset intermediate form, etc.

[0099] The computer-readable storage medium may include: any entity or device capable of carrying the computer program code, a recording medium, a USB flash drive, a mobile hard disk, a magnetic disk, an optical disc, a computer memory, a read-only memory (ROM), a random access memory (RAM), an electrical carrier signal, a telecommunication signal, and a software distribution medium, etc.

[0100] It should be noted that the content included in the computer-readable storage medium can be appropriately increased or decreased according to the requirements of legislation and patent practice in the jurisdiction. For example, in some jurisdictions, according to legislation and patent practice, the computer-readable storage medium does not include electrical carrier signals and telecommunication signals.

[0101] The above embodiments are merely one of the implementation manners capable of implementing the technical solution of the present invention. The scope of protection required by the present invention is not limited solely by this embodiment, but also includes any changes, substitutions, and other implementation manners that are easily conceivable by those skilled in the art within the technical scope disclosed by the present invention. Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to the above embodiments, those of ordinary skill in the art should understand that it is still possible to modify the specific implementation manners of the present invention or make equivalent substitutions. Any modification or equivalent substitution that does not depart from the spirit and scope of the present invention shall be covered within the scope of protection of the claims of the present invention.

Claims

1. A hybrid time slot allocation method suitable for high dynamic network cluster management, characterized in that: include: A network model is constructed based on the situation information of each node in the highly dynamic network, and at the same time, the initial networking nodes and neighbor node information table in the network model are initialized; Among them, each node in the highly dynamic network adopts clustering design; Based on the weight value of each node calculated from the neighbor node information table, the leader node is elected; The leader node allocates time slots to nodes within the preset range of the leader node, and constructs a time slot allocation table; The leader node recommends the gateway node based on the neighbor node information table to achieve initial networking; The gateway node is used to communicate with other external preset range clusters in the gateway communication frequency band; After the initial networking is successful, data communication among the nodes in the network model is carried out according to the time slot allocation table.

2. The hybrid time slot allocation method suitable for high dynamic network cluster management according to claim 1, characterized in that: The method of constructing a network model based on the situation information of each node in the highly dynamic network and initializing the initial networking nodes and neighbor node information table in the network model includes: A network model is constructed based on the situation information of each node in a highly dynamic network, and the communication frequency band is divided to obtain the communication frame structure; Based on the constructed network model, combined with the communication frame structure and the preset message structure, the initial networking nodes and the neighbor node information table are initialized; at the same time, the neighbor node information table is initialized by broadcasting control messages.

3. The hybrid time slot allocation method suitable for high dynamic network cluster management according to claim 2, characterized in that: in, The communication frequency band is divided into two frequency bands: a cluster communication frequency band and a gateway communication frequency band; wherein, if all nodes within the two-hop cluster communicate within the cluster, they all communicate in the cluster communication frequency band; if there is a need for the two-hop cluster to communicate with nodes of an external two-hop cluster, the gateway node obtained by the recommendation communicates in the gateway communication frequency band; The design process of the communication frame structure includes: a synchronization phase, a control phase, a fixed time slot allocation phase, a reserved time slot allocation phase and an isolated node competition phase; The synchronization phase is used to synchronize the clocks of all nodes. The control phase is used to build and maintain the network topology; The fixed time slot allocation phase and the reserved time slot allocation phase are used together for collision-free data interaction between nodes; The isolated node competition phase is used for isolated nodes to quickly join the network.

4. The hybrid time slot allocation method suitable for high dynamic network cluster management according to claim 1, characterized in that: The weight value of each node is calculated based on the node degree, link lifetime, average node distance, remaining energy and load degree in the neighbor node information table. The specific formula is as follows: In the formula, represents the degree of the node with ID i, represents the normalized average link survival time, represents the normalized average distance of nodes, represents the normalized value of the residual energy of the i-th node, represents the normalized load degree, , , , , Represents the weights corresponding to each parameter respectively; the weight value of the node with ID i is .

5. The hybrid time slot allocation method suitable for high dynamic network cluster management according to claim 1, characterized in that: The specific steps of the leader node election are as follows: Each node broadcasts its own weight value in turn according to the node ID. After broadcasting the weight values ​​in turn, the node with the largest weight value in the one-hop range will be elected as the preliminary leader node. If within the two-hop range of the initially elected leader node: there is only one cluster leader, which is the initially elected leader node, then the initially elected leader node shakes hands with each two-hop node in turn according to the order of its two-hop neighbor node information table; the initially elected leader node within the two-hop range sends a request to enter the network message carrying the allocated time slot to request the node to enter the network; the node that receives the request to enter the network message returns a request return message if it detects that there is no collision and broadcasts the time slot allocated to the node within the one-hop range of the node; if it detects that the time slot allocated by the initially elected leader node has been occupied by other nodes, it returns a collision message; the initially elected leader node reallocates nodes according to the collision message; after all handshakes are successful, the initially elected leader node becomes the cluster leader in the cluster within the two-hop range, and the other nodes become ordinary cluster units governed within the two-hop range of the cluster leader; and before the next control message is regularly updated, each node maintains its own time slot allocation; when a collision occurs, each node makes adjustments on its own; There are other nodes that have become cluster leaders within two hops: If there are other cluster leaders within two hops beyond the one-hop range of the currently initially elected leader node, a comparison is made at the handshake moment: the node with a larger weight value is selected as the only cluster leader within the two-hop range, and the other cluster leader with a smaller weight value is merged into the cluster leader with a larger weight value. The cluster leader with a smaller weight value broadcasts a cluster disbanding message to the nodes within its two-hop range that have been confirmed to be networked. The node that receives the cluster disbanding message becomes an isolated node and waits for handshake or competition; There are non-leader nodes that have entered other clusters within two hops: Within the two-hop range of the initially elected leader node, there are nodes within two hops that have entered other clusters: When the initially elected leader node shakes hands with the nodes within two hops, if the node has entered other two-hop networks, the node returns a request return message when it receives the network access request message again; at this time, the initially elected leader node marks the node within two hops of the leader node, and the node marks itself as an interconnected node, and at the same time announces it to the cluster leader where the node is located. The node marked as an interconnected node will become a candidate for the gateway node.

6. The hybrid time slot allocation method suitable for high dynamic network cluster management according to claim 1, characterized in that: The leader node allocates time slots to nodes within a preset range of the leader node, and constructs a time slot allocation table, including: The leader node shakes hands with the nodes within two hops of the leader node in turn and pre-allocates time slots; when there is no conflict in the allocated time slots, the node to which the time slot is allocated will occupy the time slot; if the allocated time slot conflicts with the time slot allocated by the nodes in the remaining two-hop clusters, the node to which the time slot is allocated returns a conflict message, and the leader node reallocates the time slot to the node according to the conflict message until all nodes within the two-hop range are allocated; after visiting all nodes, each node builds a time slot allocation table.

7. The hybrid time slot allocation method suitable for high dynamic network cluster management according to claim 1, characterized in that: The leader node recommends a gateway node according to the neighbor node information table, including: The leader node calculates the gateway recommendation degree of each node based on the neighbor node information table, and recommends the gateway node based on the gateway recommendation degree; When recommending a gateway, there are three situations: The first type is no interconnected nodes: If there are no interconnected nodes at this time, the leader node selects the two-hop nodes under its jurisdiction as candidate gateways, and calculates the gateway recommendation degrees of all two-hop nodes under the leader node, and selects the node with the highest recommendation degree as the gateway node; if there are no two-hop nodes, the node within one hop of the leader node becomes the candidate gateway; The second type is that there is only one interconnection node: when there is only one interconnection node, the interconnection node is recommended to become the gateway node; The third type is that there are multiple interconnected nodes: the leader node selects all interconnected nodes as candidate gateways, calculates the gateway recommendation degree of the candidate gateways respectively, and recommends the candidate gateway with the highest gateway recommendation degree as the gateway node; The average signal strength of the candidate node, the leader node, and the two-hop node is used as the gateway recommendation degree. The specific formula is as follows: In the formula, is the average signal strength of the ith node in the jth two-hop cluster, is the set of the leader node and all two-hop nodes in the j-th two-hop cluster range, is the number of all candidate gateway nodes in the jth two-hop cluster; Is a candidate gateway node With the leader node or any node in the two-hop node The wireless receiving signal strength between.

8. The hybrid time slot allocation method suitable for high dynamic network cluster management according to claim 1, characterized in that: Also includes: During the data communication process of each node, if a new node enters the network or an existing node exits the two-hop cluster range, the new node or the existing node keeps silent monitoring, enters the network or exits the two-hop cluster range during the competition access time slot, and re-books the time slot.

9. The hybrid time slot allocation method suitable for high dynamic network cluster management according to claim 1, characterized in that: Initializing the initial networking nodes and neighbor node information table in the network model includes: At this time, each node broadcasts information messages in sequence according to the order of network access ID; The nodes in the network model maintain the neighbor node information table based on the message information; The received signal strength, absolute position and mobility of the neighbor node are stored in the neighbor node information table. At the same time, the neighbor node information in the one-hop information table in the message is updated and stored in the neighbor node information table, and the neighbor node is marked as a two-hop neighbor node obtained by the one-hop node.

10. A hybrid time slot allocation system suitable for high dynamic network cluster management, characterized in that: include: A model building module is used to build a network model based on the situation information of each node in the highly dynamic network, and initialize the initial networking nodes and neighbor node information table in the network model; Among them, each node in the highly dynamic network adopts clustering design; The leader node election module is used to elect the leader node based on the weight value of each node calculated from the neighbor node information table; The time slot allocation module is used for the leader node to allocate time slots to nodes within the preset range of the leader node, and at the same time construct a time slot allocation table; The recommendation module is used for the leader node to recommend the gateway node according to the neighbor node information table to achieve initial networking; The gateway node is used to communicate with other external preset range clusters in the gateway communication frequency band; The data communication module is used to perform data communication among nodes in the network model according to the time slot allocation table after the initial networking is successful.

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