A fast networking method in a hybrid multiple access mode

Abstract

The application relates to a fast networking method in a hybrid multiple access mode and belongs to the technical field of communication networks. In the process of networking of a center node, the center node constructs and transmits a beacon frame, receives and processes a network entry request or a network entry request summary message, allocates a beacon time slot for a new network entry node, specifies a proxy node, establishes routing information, and resets a timer. In the process of networking of an already networked node, the node decides whether to adopt a network entry request summary algorithm according to a role attribute and a networking state of the node, and adjusts a data frame priority. The node receives and analyzes a NECM or NECGM message, inquires a routing table according to a destination address, and forwards the message. In the process of networking of a non-networked node, the node listens to a channel, selects a parent node after the node ends the listening, and sends a NERM to request network entry. If a valid TEI is received, the node successfully joins the network, otherwise, the node attempts to join other networks or initiates the request again. The application realizes fast networking in the hybrid multiple access mode.

Description

Technical Field

[0001] This invention belongs to the field of communication network technology and relates to a fast networking method under a hybrid multiple access mode. Background Technology

[0002] Self-organizing network (SAN) technology is a networking technique that does not rely on network infrastructure such as switches, routers, and base stations. In SAN, each node can exchange information with surrounding nodes to identify nodes it can communicate with directly, and then use routing technology to achieve communication between any nodes in the network through multi-hop relay forwarding. Because SAN does not require prior infrastructure and has the characteristic of self-organization, it is widely used in fields such as industrial monitoring, environmental monitoring, and electricity consumption information collection.

[0003] To meet the needs of different application scenarios, self-organizing networks can adopt various network topologies. In the field of resource-constrained data acquisition, tree topologies are widely used due to their ease of management and simple routing characteristics. In a tree topology network, the central node (CN) acts as the root node, responsible for controlling the entire network. A typical tree topology network is as follows: Figure 1 As shown.

[0004] In tree-topology networks, a common networking scheme is beacon-based networking. The central node periodically sends beacon frames, triggering existing network nodes to send their own. Unjoined nodes receive these beacon frames, gaining network information and identifying directly communicable existing nodes. They then select one of these identified nodes as their parent node (PN) and send messages to it to attempt to join the network. This layer-by-layer triggering process ultimately completes the establishment of the entire tree-topology network.

[0005] In the above networking scheme, the beacon frame is crucial for organizing the entire network. To ensure the transmission and reception of beacon frames, they access the channel via TDMA, thus avoiding channel usage conflicts. Simultaneously, to avoid wasting channel resources, other packets use CSMA for channel access. For specific channel usage schemes, see [link to specific scheme]. Figure 2 . Figure 2 TEI stands for Terminal Equipment Identifier, which is used to identify nodes within a network for easy communication addressing.

[0006] Although existing communication technologies have standardized this hybrid TDMA and CSMA multiple access beacon networking scheme, there is still room for improvement in practical implementation. During network deployment, the listening time of beacon frames by non-joining nodes directly affects the network's routing convergence time and topology stability. Excessive listening time leads to low network efficiency, hindering timely communication and fault recovery. Conversely, insufficient listening time may cause non-joining nodes to ignore high-quality relay nodes, resulting in unstable network connections, topology instability, increased maintenance overhead, and reduced communication reliability. Furthermore, when non-joining nodes initiate network joining requests, they need to compete for channel space with maintenance messages from existing nodes, delaying the entry of the request message into the network. When a large number of nodes request to join the network, a large number of network joining request messages are generated, increasing control overhead. Since the network topology is tree-like, messages converge at the root node. Under the CSMA channel access mechanism, large-scale network joining requests exacerbate collisions near the root node, increasing the forwarding burden on nodes, raising the probability of data loss, and prolonging network deployment time. Summary of the Invention

[0007] In view of this, the purpose of this invention is to provide a fast networking method under a hybrid multiple access mode. By reasonably setting the listening time of non-entry site, optimizing the network entry request message forwarding process, and limiting the sending time of maintenance messages, the technical problems existing in the background art are solved, thereby improving networking efficiency and shortening network networking time.

[0008] To achieve the above objectives, the present invention provides the following technical solution:

[0009] A fast networking method under a hybrid multiple access mode, the method includes three processes: networking of central nodes, networking of nodes already in the network, and networking of nodes not in the network;

[0010] The central node networking includes the following steps:

[0011] S11: The central node constructs and sends a beacon frame, and at the same time, the channel usage plan formulated by the central node is propagated through the beacon frame; when the central node clock reaches the planned TDMA time slot, the central node occupies the first time slot to broadcast the beacon frame, and at the same time starts the network timer NETWORKING_TIMER to determine the network status.

[0012] S12: The central node receives and processes the network access request message NERM or the network access request summary message NERGM.

[0013] S13: When a new node joins the network, the central node allocates a beacon time slot to the new node, designates the parent node of the new node as a proxy node, and the beacon time slot of the proxy node is located in the earlier part of the TDMA time slot. The beacon time slot of the new node is prioritized, and the central node establishes routing information for the new node and resets NETWORKING_TIMER. When a new beacon period starts, the central node sends the network-wide channel usage plan containing the new beacon time slot plan through the beacon frame, triggering a new round of network deployment.

[0014] S14: When the central node NETWORKING_TIMER overflows or the number of nodes in the network reaches the threshold, the network formation is completed. The network formation flag in the subsequent beacon frame is set to network formation complete, denoted as: NETWROKING_COMPLETED.

[0015] The networking of already connected nodes includes the following steps:

[0016] S21: When a node receives NERM, it decides whether to use the network access request aggregation algorithm based on its own role attributes and network status; when a node receives NERGM, it forwards the request directly along the path to the central node.

[0017] When sending NERM or NERGM, the node adjusts the priority of the data frame according to the network topology.

[0018] When a node detects that the network status is NETWORKING_IN_PROGRESS, it sets the frames carrying NERM and NERGM to high priority.

[0019] When a node detects that the network status is NETWROKING_COMPLETED, it sets the frame carrying NERM and NERGM to a common priority.

[0020] S22: The node receives and parses NECM or NECGM messages. If the received message is a broadcast message, the node discards it. If the node's TEI is the last hop of the message, the node restricts the received message to one hop for broadcasting. If neither of the above conditions is met, the node queries the routing table based on the final destination address and forwards the message according to the routing table entry. During the forwarding process, the node adds a new routing table entry to record the routing information from the current node to the node that successfully obtained a valid TEI. At the same time, when the network is in the NETWORKING_IN_PROGRESS state, the node sets the frames carrying NECM or NECGM as high priority for forwarding.

[0021] S23: After receiving and parsing the beacon frame, the node completes time synchronization, calculates the time slot for sending its own beacon frame, updates the stored network attributes, and constructs its own beacon frame.

[0022] The networking of nodes not yet connected to the network includes the following steps:

[0023] S31: The node listens to the channel. If the node receives a valid beacon frame for the first time, it calculates the remaining time of the TDMA time slot of the network based on the time slot allocation information in the beacon frame, and sets and starts a listening timer MONITOR_TIMER; the node continues to receive beacon frames.

[0024] The valid beacon frame is one in which the network access permission flag is set to ALLOWED_ENTRY, and the node has not marked the failure of its attempt to join the network.

[0025] S32: The node ends listening, selects a parent node from the sending nodes of the received beacon frames according to the relay node selection policy, adjusts its own time to synchronize with the network time, sends a NERM to the selected parent node, and starts the network access confirmation waiting timer NETWORK_ENTRY_CONFIRMATION_WAIT_TIMER to wait for the parent node's network access confirmation.

[0026] S33: When a node receives a broadcast NECM or NECGM, it resolves the TEI value corresponding to the node. If the node obtains a valid TEI, it successfully joins the network, becomes a network-connected node, records the parent node, establishes a routing table to the central node, and initiates the network maintenance process. If the node obtains an invalid INVALID_TEI, it fails to join the network and attempts to join another network. If, during the network joining confirmation process, the node does not receive a NECM / NECGM with its own MAC address, and NETWORK_ENTRY_CONFIRMATION_WAIT_TIMER overflows, the node can attempt to join another network or re-initiate a request to that network.

[0027] Furthermore, in S11, the beacon frame's field information includes: network identifier, central node address, terminal device identifier, network formation flag, allow network entry flag, beacon timestamp, beacon period start time, beacon period length, beacon time slot length, total number of beacons, total number of proxy nodes, and beacon allocation information; the network formation flag indicates that network formation is in progress, denoted as NETWORKING_IN_PROGRESS, and the allow network entry flag indicates that joining is allowed, denoted as ALLOWED_ENTRY.

[0028] Furthermore, in S12, the central node receives and processes the network access request message NERM or the network access request summary message NERGM, specifically as follows:

[0029] The central node receives NERM or NERGM and verifies the legitimacy of the requesting node within the network according to the whitelist. For nodes that pass verification, the central node assigns a TEI. For nodes that fail verification, the central node does not record it but assigns an invalid device identifier, denoted as INVALID_TEI, to indicate that the node does not belong to the network. The central node returns the assigned TEI to the node via the network entry confirmation message NECM and the network entry confirmation summary message NECGM along the original path. When the network state is NETWORKING_IN_PROGRESS, NECM and NECGM are sent as high-priority data frames.

[0030] Furthermore, in S12, when the central node is the parent node of the requesting node to join the network, the central node responds using NECGM. That is, when the central node receives multiple NERMs, it uses the network entry request aggregation algorithm of the already joined nodes to process them, and treats the multiple received NERMs as NERGMs for processing and response.

[0031] Furthermore, in S14, the threshold for the number of nodes in the network is determined by the number of nodes in the whitelist by default. Once the network is completed, the nodes that have joined the network are instructed not to execute the network entry request aggregation algorithm and maintain the message sending time limit mechanism. The entire network does not send or forward network entry related messages with high-priority data frames. When the network flag bit in the beacon frame received by a node that has not joined the network is NETWROKING_COMPLETED, it can still initiate a network entry request. When the number of nodes in the network reaches the threshold, the beacon frame's network entry permission flag bit is set to disallowed, denoted as DENIED_ENTRY.

[0032] Furthermore, in S21, when a node receives NERM, it determines whether to use the network access request aggregation algorithm based on its own role attributes and network status, specifically as follows:

[0033] When a node is a proxy node or the network status is NETWROKING_COMPLETED, the node directly forwards NERM along the path to the central node; otherwise, the node uses the network access request aggregation algorithm to generate NERGM for reporting.

[0034] In the network access request aggregation algorithm, a network access request aggregation timer and a threshold for the number of aggregation nodes are introduced. The network access request aggregation timer is denoted as: NETWORK_ENTRY_REQUEST_GATHER_TIMER; when

[0035] If NETWORK_ENTRY_REQUEST_GATHER_TIMER overflows or the number of collected NERMs reaches the threshold for the number of aggregation nodes, then the NERGM construction is completed and the message reporting process begins.

[0036] The timer duration is set to allow time for the central node to return to NECGM within this round of beacon cycle;

[0037] The principle for setting the duration of a timer is expressed as follows:

[0038]

[0039] T reserved =α×RTT (2)

[0040] in, It is the maximum value set for the timer duration, T. current It is the current network time as assessed by the node, T reserved This is the reserved time. RTT is the round-trip time to the central node as evaluated by the node, which is set based on the transmission and reception of beacon frames or historical values. α is the adjustment coefficient.

[0041] Furthermore, nodes already in the network periodically send maintenance messages, deciding whether to activate the maintenance message sending time limit mechanism based on their own role and status. In this mechanism, the CSMA time slot is divided into two periods: a maintenance message sending limit and a maintenance message sending time. During the maintenance message sending time period, the node sends maintenance messages. The maintenance message sending limit segment consists of two parts: an absolute limit and a variable limit. The absolute limit is the minimum value of the maintenance message sending limit segment; the variable limit is determined by the node based on its own status. The node calculates the absolute limit time using the following formula:

[0042] T R =T start +n total ×T beacon +T back_off (3)

[0043] Among them, T R It is the end time of the absolute limit, n total It is the total number of beacon slots in the beacon frame, T. back_off The size depends on the parameter settings of the CSMA / CA algorithm used by the system, and the default value is the maximum value of backoff when sending messages;

[0044] When T current ≤T RDuring this time, maintenance messages are queued in the sending queue; after the absolute restriction ends, the node determines whether the network access request aggregation algorithm has been started. If the node is currently performing network access request aggregation, the node's maintenance messages continue to queue.

[0045] Furthermore, in S23, the time slot for the calculation node to send beacon frames is expressed by the formula:

[0046] T i =T start +C i ×T beacon (4)

[0047] Among them, T start This is the start time of the current beacon cycle, obtained from the beacon cycle start time field in the beacon frame. (C) i Node i queries the beacon allocation information in the beacon frame and finds its own TEI count value from the first record. beacon It is the value of the beacon slot length field in the beacon frame; when C i ≤n proxy At that time, node i is instructed to become the proxy node, n proxy This represents the total number of proxy nodes in the beacon frame; node i in T i It constantly sends its own beacon frames.

[0048] Furthermore, in S31, after receiving the beacon frame, the non-network-connected node calculates the remaining time of the TDMA time slot, and the calculation formula is expressed as follows:

[0049]

[0050] in, C represents the listening duration of node j. i It is the count value of node i that sends beacon frames in the time slot allocation information.

[0051] Furthermore, during the networking process of nodes not yet joining the network, after S31 ends, the nodes not yet joining the network enter S32 before the absolute restriction ends; while in S32, the nodes not yet joining the network can still receive beacon frames; the information of valid beacon frames is stored for the node to change its target; after the node successfully joins the network, the redundant beacon frame information is cleared; if the node fails to join the network, if there is other network information, there is no need to repeat S31, and it can directly enter S32 to try to join a new network.

[0052] The beneficial effects of this invention are as follows:

[0053] First, this invention accelerates the process of non-networked nodes initiating network joining. Through a channel listening mechanism based on beacon information, this invention controls the listening time of non-networked nodes to within the TDMA time slots of the networks they can join. This ensures sufficient selection space for relay nodes without excessively long listening times. Furthermore, this invention implements a maintenance message sending time limit mechanism at the network edge, requiring non-networked nodes to enter the NERM sending process before the absolute limit expires. This eliminates interference from maintenance messages within the network, ensuring the network receives the NERM message as early as possible. In addition, this invention prioritizes the allocation of beacon time slots to newly joining nodes at the central node, promoting network discovery and accelerating their network joining requests. Finally, for multi-network scenarios, this invention preserves the ability of non-networked nodes to receive and process beacons from other networks. When a network joining attempt fails, a new attempt can be initiated directly without re-listening to the channel.

[0054] Second, the message propagation during the network entry process is optimized. This invention introduces a network entry request aggregation algorithm, allowing already-joined nodes at the network edge to aggregate NERMs sent by multiple non-joined nodes, and instead using NERGM for propagation within the network. This reduces message control overhead, lowers the probability of collisions caused by uplink message aggregation, and alleviates the forwarding processing pressure on nodes. Simultaneously, the priority of data frames is increased during the sending or forwarding of related messages, enhancing the ability of messages to preempt the channel in CSMA time slots.

[0055] Third, intelligent adjustment of network topology strategy is achieved. When no new nodes join the network within a certain period, or when all nodes in the whitelist have joined the network, it is assumed that the system will not experience a large number of nodes initiating network joining. At this point, the network is basically formed, and there is no need to invest too many resources in network topology. Therefore, this invention uses NETWORKING_TIMER combined with whitelist verification at the central node to identify the network topology status and uses beacon frames to inform all nodes in the network. In the NETWORKING_COMPLETED state, the network joining request aggregation algorithm is not executed, allowing for faster connection establishment with the central node when a small number of nodes need to join the network. At the same time, the sending priority of network joining related messages is restored in this state, and the maintenance message sending time limit mechanism is turned off, enabling the network to better serve business needs.

[0056] Other advantages, objectives, and features of the invention will be set forth in part in the description which follows, and in part will be apparent to those skilled in the art from the following examination, or may be learned from practice of the invention. The objectives and other advantages of the invention can be realized and obtained through the following description. Attached Figure Description

[0057] To make the objectives, technical solutions, and advantages of the present invention clearer, the preferred embodiments of the present invention will be described in detail below with reference to the accompanying drawings, wherein:

[0058] Figure 1 Network topology diagram

[0059] Figure 2 This is a schematic diagram of the channel usage scheme;

[0060] Figure 3 A flowchart illustrating the process of a central node receiving network access request messages.

[0061] Figure 4 A flowchart illustrating the processing of network access request summary messages received by the central node;

[0062] Figure 5 Flowchart for NERM / NERGM reception and processing of nodes already in the network;

[0063] Figure 6 Flowchart of the network request aggregation algorithm;

[0064] Figure 7 Flowchart for NECM / NECGM reception and processing of nodes already in the network;

[0065] Figure 8 A schematic diagram of a channel usage scheme for maintaining a message transmission time limit mechanism;

[0066] Figure 9 Flowchart for maintaining message sending for nodes already in the network;

[0067] Figure 10 Flowchart for maintaining the message sending time limit mechanism

[0068] Figure 11 Flowchart for channel monitoring of nodes not yet connected to the network

[0069] Figure 12 This is a flowchart illustrating the message exchange process during network formation.

[0070] Figure 13 This is a tree network topology diagram for an example;

[0071] Figure 14 This is the new round of channel usage planning diagram in Example 1;

[0072] Figure 15 This is a schematic diagram of the temporal sequence of node behaviors in Example 1;

[0073] Figure 16 This is a schematic diagram of the NERM conversion to NERGM at node 4 in Example 2;

[0074] Figure 17This is a schematic diagram of the time sequence of key behaviors of some nodes in Example 2.

[0075] Figure 18 This is a schematic diagram illustrating the execution time sequence of the message sending time limit mechanism maintained by nodes 4 and 5 in Example 2. Detailed Implementation

[0076] The following specific examples illustrate the implementation of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and various details in this specification can be modified or changed based on different viewpoints and applications without departing from the spirit of the present invention. It should be noted that the illustrations provided in the following embodiments are only schematic representations of the basic concept of the present invention. Unless otherwise specified, the following embodiments and features can be combined with each other.

[0077] The accompanying drawings are for illustrative purposes only and are schematic diagrams, not actual pictures. They should not be construed as limiting the invention. To better illustrate the embodiments of the invention, some parts in the drawings may be omitted, enlarged, or reduced, and do not represent the actual product dimensions. It is understandable to those skilled in the art that some well-known structures and their descriptions may be omitted in the drawings.

[0078] In the accompanying drawings of the embodiments of the present invention, the same or similar reference numerals correspond to the same or similar components. In the description of the present invention, it should be understood that if terms such as "upper," "lower," "left," "right," "front," and "rear" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, they are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, the terms used to describe positional relationships in the drawings are only for illustrative purposes and should not be construed as limiting the present invention. For those skilled in the art, the specific meaning of the above terms can be understood according to the specific circumstances.

[0079] Please see Figures 1 to 18 This is a fast networking method under a hybrid multiple access mode.

[0080] This invention describes the networking process from three perspectives: the central node, nodes already in the network, and nodes not yet in the network.

[0081] The central node networking process is as follows:

[0082] Step 1: The central node constructs and sends a beacon frame. The beacon frame should contain the fields listed in Table 1, where the network formation flag indicates that network formation is in progress (denoted as NETWORKING_IN_PROGRESS), and the allow-to-join flag indicates that joining is permitted (denoted as ALLOWED_ENTRY). The channel usage plan formulated by the central node is also propagated through the beacon frame. When the central node clock reaches the planned TDMA time slot, the central node occupies the first time slot to broadcast the beacon frame. At the same time, the network formation timer (denoted as NETWORKING_TIMER) is started to determine the network status. Table 1 shows the necessary fields for the beacon frame.

[0083] Table 1

[0084]

[0085] Step 2: The central node receives and processes the Network Entry Request Message (NERM) or Network Entry Request Gather Message (NERGM). Upon receiving the NERM or NERGM, the central node verifies the legitimacy of the requesting node within the network based on the whitelist. For nodes that pass verification, the central node assigns them a TEI. For nodes that fail verification, the central node makes no record but assigns an invalid device identifier, denoted as INVALID_TEI, to indicate that the node does not belong to this network. The central node then returns the assigned TEI to the node via the original path using a Network Entry Confirmation Message (NECM) and a Network Entry Confirmation Gather Message (NECGM). (The last sentence appears to be incomplete and possibly refers to a different topic.)

[0086] NETWORKING_IN_PROGRESS sends NECM and NECGM as high-priority data frames.

[0087] Step 3: When a new node joins the network, the central node needs to allocate a beacon time slot to the new node and designate its parent node as a proxy node. The proxy node's beacon time slot must be guaranteed and located in the early part of the TDMA time slot allocation. The beacon time slot for the new node needs to be prioritized. In addition, the central node needs to add the routing information to the new node and reset the NETWORKING_TIMER. The processing flow for the central node receiving NERM and NERGM is as follows: Figure 3 and Figure 4As shown. After the new beacon cycle begins, the central node distributes the network-wide channel usage plan, which includes the new beacon time slot plan, through the beacon frame, triggering a new round of network deployment.

[0088] Step 4: When the central node's NETWORKING_TIMER overflows or the number of nodes in the network reaches the threshold, the network is considered complete, and the network completion flag in subsequent beacon frames will be set to NETWROKING_COMPLETED. The threshold for the number of nodes in the network is determined by the number of nodes in the whitelist by default, but it can also be configured manually. Network completion marks the end of the network setup phase, indicating that nodes already in the network do not need to execute the network entry request aggregation algorithm or maintain the message sending time limit mechanism, and the entire network does not need to send or forward network entry related messages with high priority data frames. Nodes not yet in the network can still initiate network entry requests if they receive a beacon frame with the network completion flag set to NETWROKING_COMPLETED. If the number of nodes in the network reaches the threshold, the network entry permission flag in the beacon frame must also be set to DENIED_ENTRY (see Table 2 for the network entry confirmation summary message fields).

[0089] Table 2

[0090]

[0091] In step 2 above, the NECGM message fields are shown in Table 2. It is worth noting that the central node typically responds to NERM with NECM and to NERGM with NECGM. However, when the central node is the parent node of a requesting node to join the network, the central node can respond using NECGM. In this special case, the central node needs to use the network entry request aggregation algorithm for already joined nodes to treat multiple received NERMs as NERGMs for processing and response.

[0092] During the process of initiating network formation, the central node also needs to perform network maintenance to ensure that the nodes that have joined the network do not disconnect.

[0093] The networking process for nodes that have already joined the network is as follows:

[0094] Step 1: The node receives and parses the beacon frame, completes time synchronization, calculates the time slot for sending its own beacon frame, updates the stored network attributes, and constructs its own beacon frame.

[0095] T i =T start +C i ×T beacon (1)

[0096] The above formula is the formula for node i to calculate its own beacon transmission time, where T i T is the beacon transmission time of node i. startThis is the start time of the current beacon cycle, obtained from the beacon cycle start time field in the beacon frame. (C) i Node i queries the beacon allocation information in the beacon frame and finds its own TEI count value from the first record. beacon This is the value of the beacon slot length field in the beacon frame. When C i ≤n proxy At that time, node i is instructed to become the proxy node, n proxy This represents the total number of proxy nodes in the beacon frame. Node i in T i It constantly sends its own beacon frames.

[0097] Step 2: Nodes receive either NERM or NERGM messages, with different processing flows for each. When a node receives NERM, it needs to determine whether to use the network entry request aggregation algorithm based on its role and network status. If the node is a proxy node or the network status is NETWROKING_COMPLETED, the node directly forwards the NERM along the path to the central node. Otherwise, the node needs to use the network entry request aggregation algorithm to generate an NERGM message for reporting. When a node receives NERGM messages, it directly forwards them along the path to the central node. The NERM and NERGM reception processes are as follows: Figure 5 As shown, the algorithm flow for summarizing network access requests is as follows: Figure 6 As shown in Table 3, which provides the field information for NERGM, when sending NERM or NERGM, the node needs to adjust the priority of the data frame according to the network topology. When the node detects that the network topology is NETWORKING_IN_PROGRESS, the node sets the frame carrying NERM and NERGM to a high priority. When it is NETWROKING_COMPLETED, the frame carrying NERM and NERGM is set to a general priority. Table 3 is the summary message field table for network access request.

[0098] Table 3

[0099]

[0100] Step 3: Receive and parse NECM / NECGM. If the node receives a broadcast message of this type, it discards it. If the node's TEI is the last hop of the message, the node will restrict the received message to broadcast within one hop. Otherwise, the node queries its routing table based on the final destination address and forwards the message. If the message is not discarded, it also needs to be added to the routing table entry of the node that successfully obtained the valid TEI. The specific process of this step is as follows: Figure 7 As shown. Similarly, when the network state is NETWORKING_IN_PROGRESS, the node will prioritize forwarding frames carrying NECM or NECGM.

[0101] The above-mentioned network access request aggregation algorithm introduces a network access request aggregation timer (denoted as ).

[0102] The `NETWORK_ENTRY_REQUEST_GATHER_TIMER` and the threshold number of aggregation nodes jointly determine the completion of a NERGM construction. When `NETWORK_ENTRY_REQUEST_GATHER_TIMER` overflows or the number of collected NERGMs reaches the threshold number of aggregation nodes, the NERGM construction is complete, and the message reporting process begins. The timer duration should be set to allow sufficient time for the central node to return the NECGM within the current beacon cycle.

[0103]

[0104] T reserved =α×RTT (3)

[0105] The above formula describes the principle of timer setting. It is the maximum value set for the timer duration, T. current It is the current network time as assessed by the node, T reserved This refers to the reserved time. RTT is the round-trip time to the central node as assessed by the node, which can be set based on the transmission and reception of beacon frames or historical values. α is an adjustment factor. Since RTT is based on beacon frame assessment and cannot reflect congestion retransmissions and the central node's processing, the reserved time is amplified by the adjustment factor. The threshold for the total number of nodes can be configured manually or calculated based on the capacity of a single MAC frame carrying NECGM.

[0106] The above process describes the operational flow of nodes already in the network during network formation. In actual network configurations, nodes also need to perform network maintenance, such as periodically sending maintenance messages to maintain connections with neighboring nodes. Agent nodes need to collect connection information between themselves and their child nodes and report it to the central node.

[0107] During the network deployment phase, existing nodes sending maintenance messages need to decide whether to enable a maintenance message transmission time limit mechanism based on their own role and status. Under this mechanism, existing nodes need to reduce the CSMA time slot resources available for maintenance messages. Specific channel usage schemes are as follows... Figure 8 As shown in the diagram, the CSMA time slot is divided into two time periods. Nodes can only send maintenance messages during the maintenance message sending period. The maintenance message sending restriction segment consists of two parts: an absolute limit and a variable limit. The absolute limit is the minimum value of the maintenance message sending restriction segment. The variable limit is determined by the node based on its own state.

[0108] After introducing the above mechanism, the process for network-connected nodes to send maintenance messages is as follows: Figure 9As shown. This mechanism requires nodes to calculate the absolute limit time, calculated using the following formula:

[0109] T R =T start +n total ×T beacon +T back_off (4)

[0110] Where T R It is the end time of the absolute limit, n total It is the total number of beacon slots in the beacon frame, T. back_off The size depends on the parameter settings of the CSMA / CA algorithm used by the system, and the default value is the maximum value that needs to be backed up when sending a message. When T current ≤T R During this process, maintenance messages need to be queued in the sending queue. After the absolute restriction ends, the node needs to determine whether the network access request aggregation algorithm has been enabled. If the node is currently performing network access request aggregation, its maintenance messages need to continue to queue. The mechanism process is as follows: Figure 10 As shown.

[0111] The networking process for nodes not yet connected to the network is as follows:

[0112] Step 1: The node listens to the channel. If a beacon frame is received, the information is extracted. If it is the first valid beacon frame received, the end time of the network's TDMA time slot is calculated, and a listening timer (denoted as MONITOR_TIMER) is set and started. The node continues to receive beacon frames. A valid beacon frame is one in which the allow-to-join flag indicates ALLOWED_ENTRY, and the node has not marked the attempt to join the network as failed.

[0113]

[0114] The above formula is used to calculate the remaining time of the TDMA time slot after a non-networked node receives a beacon frame. C represents the listening duration of node j. i This is the count value of node i, which sends the beacon frame, in the time slot allocation information. The channel listening process is as follows: Figure 11 As shown.

[0115] Step 2: The node ends listening and selects a parent node from the sending nodes of the received beacon frames according to the relay node selection policy. The node synchronizes its time with the network, then sends a NERM to the selected parent node and starts a network entry confirmation waiting timer (denoted as NETWORK_ENTRY_CONFIRMATION_WAIT_TIMER).

[0116] Step 3: Upon receiving the broadcast NECM / NECGM, the node resolves its corresponding TEI value. If the node obtains a valid TEI, it successfully joins the network, becomes an already joined node, records its parent node, establishes a routing table to the central node, and initiates network maintenance procedures. If the node obtains an invalid INVALID_TEI, it marks the attempt to join the network as failed and attempts to join another network. If NETWORK_ENTRY_CONFIRMATION_WAIT_TIMER overflows and the node does not receive a NECM / NECGM with its own MAC address, the node can attempt to join another network or re-initiate a request to that network.

[0117] After step 1, nodes not yet joining the network should complete step 2 as soon as possible. Nodes not yet joining the network must enter the NERM transmission process before the absolute restriction expires. While performing step 2, nodes not yet joining the network can still receive beacon frames. Information from valid beacon frames will be stored for nodes to attempt to change their target. After a node successfully joins the network, redundant beacon frame information is cleared. If a node's network joining attempt fails, and there is information from other networks, it does not need to repeat step 1; it can directly proceed to step 2 to attempt to join a new network.

[0118] Figure 12 The diagram illustrates the message exchange flow during network formation. As shown, the end of listening for nodes not yet joining the network is determined by receiving beacon frames, thus limiting the listening period to the TDMA time slot of the network the node is preparing to join. After a certain waiting time, multiple NERM requests can be converted into a single NERGM for reporting.

[0119] To more clearly illustrate the application of the present invention in practical scenarios, specific embodiments of the present invention will be given below. Figure 13 It is a specific tree network topology diagram. For ease of description, Figure 13 This greatly simplifies the number of nodes. Correspondingly, the variable values ​​used in this invention have also been scaled accordingly. To further simplify the description, Figure 13 The node number is used as the TEI of each node in the embodiment, where node 1 is the central node.

[0120] Example 1: Layer 1 node joining the network

[0121] This example illustrates the interaction process between the central node (node ​​1) and the nodes not yet connected to the network (node ​​2 and node 3) during the networking process.

[0122] Step 1: After determining the channel usage scheme for this network, Node 1 sends a beacon frame in the first time slot of the TDMA time slot. The beacon frame contains a network setup flag indicating NETWORKING_IN_PROGRESS and an allow-to-entry flag indicating ALLOWED_ENTRY. Simultaneously, after Node 1 initiates the network setup phase, it starts the NETWORKING_TIMER.

[0123] Step 2: Nodes 2 and 3 receive the beacon frame. After parsing it, they find that the NID is not marked and indicates that they can join the network. Based on the beacon frame's time slot information, Nodes 2 and 3 calculate the listening time and activate their respective MONITOR_TIMERs. After the MONITOR_TIMER overflows, Nodes 2 and 3 select Node 1 as their parent node and synchronize their time to the network. Nodes 2 and 3 compete for the channel using CSMA / CA and send NERM to Node 1.

[0124] Step 3: Let's assume Node 2 preempts the channel first, and Node 1 does not use the network access request summarization algorithm. Node 1 receives NERMs from Node 2 and Node 3 successively. After receiving NERM from Node 2, Node 1 extracts the MAC address information and iterates through the whitelist. After finding Node 2's MAC address, it assigns TEI 2 to Node 2, broadcasts NECM using high-priority frames, adds Node 2 to the routing table, allocates a beacon time slot to Node 2, and finally resets NETWORKING_TIMER.

[0125] Step 4: Both Node 2 and Node 3 receive the NECM from Step 3 above. After parsing, Node 2 successfully obtains the TEI and records the parent node as Node 1. After parsing, Node 3 finds that the MAC address does not match and discards the packet.

[0126] Step 5: Let's assume that node 3 fails the whitelist verification. After node 1 assigns an invalid INVALID_TEI to it, it broadcasts NECM.

[0127] Step 6: Nodes 2 and 3 receive the NECM from Step 5. Node 2, now an already joined node, recognizes the message as broadcast and discards it. Node 3 parses the message and finds the INVALID_TEI invalid, marking the current network as a failed joining attempt and checking for valid beacon frame information. Finding no valid information, Node 3 re-enters the channel listening phase, waiting for beacon frames from the new network.

[0128] Step 7: Node 1 sends a new beacon frame, disseminating the new time slot plan via the beacon frame. The new channel usage scheme is as follows: Figure 14 As shown.

[0129] Step 8: After receiving the beacon frame, Node 2 parses the time slot plan and sends the beacon frame in the corresponding time slot. After receiving the beacon frame, Node 3 finds that the network has been marked and discards the beacon frame.

[0130] The order of behavior of each node within one beacon cycle in the above process is as follows: Figure 15 As shown in Table 4, after Node 2 joins the network, the routing table of Node 1 is as follows.

[0131] Table 4

[0132] 2 2 1

[0133] Example 2: Three-layer node network access

[0134] This example illustrates the interaction process between nodes not yet in the network (nodes 7, 8, 9, 10, and 11) and nodes already in the network (nodes 2, 3, 4, 5, and 6) during the network formation process, and explains the operation of the maintenance message sending time limit mechanism.

[0135] Step 1: Nodes 4 and 5 receive the beacon frame from Node 2, parse the time slot arrangement in the beacon frame, and wait for their own time to send a beacon frame. Node 6 also receives the beacon frame from Node 3 and takes the same steps. Nodes 4, 5, and 6 then send beacon frames in their respective time slots according to the time slot arrangement of the beacon frame.

[0136] Step 2: During the listening phase, nodes 7, 8, and 9 receive beacon frames from nodes 4 and 5, while nodes 10 and 11 receive beacon frames from node 6. After their respective parent nodes are selected, nodes 7 and 8 select node 4, node 9 selects node 5, and nodes 10 and 11 select node 6, and each sends a NERM message to node 6.

[0137] Step 3: Let's assume Node 4 receives the NERM from Node 7 first. Node 4 is not a proxy node at this point, and the current beacon frame indicates NETWORKING_IN_PROGRESS, so Node 4 begins executing the network entry request summarization algorithm. Let's assume the summarization node threshold is 2, so when Node 4 receives the NERM from Node 8, Node 4 completes the NERGM construction and sends the NERGM to Node 2. Similarly, Node 6 sends the NERGM to Node 3. Node 5 has only received one NERM and needs to send the NERGM to Node 2 after NETWORK_ENTRY_REQUEST_GATHER_TIMER overflows. Nodes 4, 5, and 6 use high-priority data frames when sending NERGMs.

[0138] Step 4: Node 2 forwards the NERGM from Node 4 and Node 5 to Node 1 in sequence, and Node 3 does the same. The forwarding process also uses high-priority data frames.

[0139] Step 5: Node 1 processes the NERGMs in the order they are received. Assuming Node 11 fails verification, Node 2 processes the NERGM forwarded from Node 4 first, followed by the NERGM forwarded from Node 3, and finally the NERGM forwarded from Node 5. During this process, Node 1 retrieves the node information from each NERGM and performs whitelist verification. The processing of each node's information is described in step 3 of Example 1. When processing NERGMs, Node 1 prepares the corresponding NECGM in advance and then fills in the required content of the NECGM according to the processing status of each node.

[0140] Step 6: Node 2 receives two NECGMs in succession and adds routing information to Nodes 7, 8, and 9. After receiving the NECGM, Node 3 adds the routing information to Node 10. Both Node 2 and Node 3 query their routing tables based on the final destination address of the frame carrying the NECGM and forward it with high priority.

[0141] Step 7: Node 4 receives the corresponding NECGM first. After parsing it, it finds that the final destination address of the frame carrying the message is itself. Node 4 adds it to the routing information of Nodes 7 and 8, and then broadcasts the NECGM. At this time, due to the shared channel characteristic, Nodes 2 and 5 can also receive the message. Since they have already joined the network, they discard the broadcast message upon receiving it. Nodes 5 and 6 subsequently adopt the same processing scheme. The NECGM received by Node 6 indicates that Node 11 failed to join the network, and Node 6 only adds it to the routing information of Node 10.

[0142] Step 8: Nodes 7, 8, and 9 first receive the NECGM broadcast by Node 4. Nodes 7 and 8 successfully resolve to TEI and successfully join the network. Node 9 cannot find its own information through this NECGM and continues to wait. Nodes 7, 8, and 9 receive the NECGM broadcast by Node 5. Nodes 7 and 8 are already network-connected and discard the message. Node 9 resolves to TEI from this message and completes network entry. Nodes 10 and 11 receive the NECGM broadcast by Node 6. Node 10 resolves to TEI and successfully joins the network. Although Node 11 resolves to INVALID_TEI, it is an invalid value, and network entry fails; it prepares to try switching networks.

[0143] Figure 16 A schematic diagram illustrating the changes in the network entry request packets at node 4 is provided. This example demonstrates that the original five NERM packets, after aggregation, only require three packets to be forwarded at nodes 2 and 3 to reach node 1. The advantages of this approach are obvious when dozens or even hundreds of nodes request to join the network. Figure 17The behavior of nodes 4, 5, 7, 8, and 9 at certain points during the network entry process is shown.

[0144] In step 3, if nodes 4 and 5 are ready to send maintenance messages immediately after entering the CSMA time slot, node 4 detects that the network time is in the absolute time constraint phase and suspends maintenance message transmission. When node 4's absolute time constraint ends, it finds that the network access request message summarization algorithm has not been executed, and node 4 sends a maintenance message. Node 5, like node 4, suspends maintenance message transmission during the absolute time constraint phase. When node 5's absolute time constraint ends, it finds that the network access request summarization algorithm is being executed, and node 5 continues to wait to send. When node 5's NETWORK_ENTRY_REQUEST_GATHER_TIMER overflows, node 5 sends NERGM first, and then sends its own maintenance message. The execution time sequence of this process is as follows: Figure 18 As shown.

[0145] Example 3: Networking Strategy Adjustment

[0146] This example will describe how the central node identifies the network status and influences the network strategy through the network flag and the allowed network entry flag in the beacon frame.

[0147] Assuming when Figure 13 All nodes in the first three layers are connected to the network. Node 12 has restarted due to a fault and has not yet connected to the network. Node 13 failed to receive beacon frames and therefore cannot connect to the network. Furthermore, assuming that the whitelist configured at node 1 contains 11 nodes, excluding node 13, the network topology is as follows:

[0148] Step 1: Node 1 experiences a NETWORKING_TIMER overflow due to not receiving a successful network entry request for a period of time. Node 1 schedules a new round of beacon frames, with the network configuration flag indicating NETWORKING_COMPLETED in the beacon frame.

[0149] Step 2: Each node already in the network receives the beacon frame from its parent node, parses the change in network status, and updates its network attribute information. Then, according to the instructions in the beacon frame, each node sends its own beacon frame.

[0150] Step 3: Node 12 receives the beacon frame from Node 7 and follows the same processing procedure as in Examples 1 and 2, finally sending NERM to Node 7.

[0151] Step 4: Node 7 receives the NERM and checks its network attribute, which is NETWORKING_COMPLETED. Node 7 forwards the NERM directly without performing aggregation. Along the path from Node 7 to Node 1, each node forwards the packet sequentially. This forwarding process uses data frames with general priority.

[0152] Step 5: Node 1 receives the network access request from Node 12, following the same processing flow as in Examples 1 and 2. Furthermore, after the whitelist verification is successful, Node 1 determines that all nodes in the whitelist have joined the network, updates its network attributes, and the allowed network access flag in subsequent beacon frames indicates DENIED_ENTRY.

[0153] Step 6: After successfully joining the network, Node 12 waits for a new round of beacon frame instructions. In the new beacon cycle, Node 12 updates its network attributes and sends a beacon frame in the corresponding time slot.

[0154] Step 7: After receiving the beacon frame from node 12, node 13 parses the DENIED_ENTRY flag, discards the beacon frame, and continues channel monitoring.

[0155] In this example, node 1 controls the aggregation behavior of network entry requests from already joined nodes through the network formation flag in the beacon frame, and informs non-joining nodes to give up trying to join this network through the allow network entry flag in the beacon frame.

[0156] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the present invention, and all such modifications or substitutions should be covered within the scope of the claims of the present invention.

Claims

1. A rapid networking method under a hybrid multiple access mode, characterized in that: This method includes three processes: networking of central nodes, networking of nodes already in the network, and networking of nodes not yet in the network. The central node networking includes the following steps: S11: The central node constructs and sends a beacon frame, and at the same time, the channel usage plan formulated by the central node is propagated through the beacon frame; when the central node clock reaches the planned TDMA time slot, the central node occupies the first time slot to broadcast the beacon frame, and at the same time starts the network timer NETWORKING_TIMER to determine the network status. S12: The central node receives and processes the network access request message NERM or the network access request summary message NERGM. S13: When a new node joins the network, the central node allocates a beacon time slot to the new node, designates the parent node of the new node as a proxy node, and the beacon time slot of the proxy node is located in the earlier part of the TDMA time slot. The beacon time slot of the new node is arranged first, and the central node establishes routing information for the new node and resets NETWORKING_TIMER. When a new beacon cycle begins, the central node sends out the network-wide channel usage plan, which includes the new beacon time slot plan, through the beacon frame, triggering a new round of network deployment. S14: When the central node NETWORKING_TIMER overflows or the number of nodes in the network reaches the threshold, the network formation is completed. The network formation flag in the subsequent beacon frame is set to network formation complete, denoted as: NETWORKING_COMPLETED. The networking of already connected nodes includes the following steps: S21: When a node receives NERM, it decides whether to use the network access request aggregation algorithm based on its own role attributes and network status; when a node receives NERGM, it forwards the request directly along the path to the central node. When sending NERM or NERGM, the node adjusts the priority of the data frame according to the network topology. When a node detects that the network status is NETWORKING_IN_PROGRESS, it sets the frames carrying NERM and NERGM to high priority. When a node detects that the network status is NETWORKING_COMPLETED, it sets the frame carrying NERM and NERGM to a common priority. S22: The node receives and parses NECM or NECGM messages. If the received message is a broadcast message, the node discards it. If the node's TEI is the last hop of the message, the node restricts the received message to one hop for broadcasting. If neither of the above conditions is met, the node queries the routing table based on the final destination address and forwards the message according to the routing table entry. During the forwarding process, the node adds a new routing table entry to record the routing information from the current node to the node that successfully obtained a valid TEI. At the same time, when the network is in the NETWORKING_IN_PROGRESS state, the node sets the frames carrying NECM or NECGM as high priority for forwarding. S23: After receiving and parsing the beacon frame, the node completes time synchronization, calculates the time slot for sending its own beacon frame, updates the stored network attributes, and constructs its own beacon frame. The networking of nodes not yet connected to the network includes the following steps: S31: The node listens to the channel. If the node receives a valid beacon frame for the first time, it calculates the remaining time of the TDMA time slot of the network based on the time slot allocation information in the beacon frame, and sets and starts a listening timer MONITOR_TIMER; the node continues to receive beacon frames. The valid beacon frame is one in which the network access permission flag is set to ALLOWED_ENTRY, and the node has not marked the failure of its attempt to join the network. S32: The node ends listening, selects a parent node from the sending nodes of the received beacon frames according to the relay node selection policy, adjusts its own time to synchronize with the network time, sends a NERM to the selected parent node, and starts the network access confirmation waiting timer NETWORK_ENTRY_CONFIRMATION_WAIT_TIMER to wait for the parent node's network access confirmation. S33: When a node receives a broadcast NECM or NECGM, it resolves the TEI value corresponding to the node. If the node obtains a valid TEI, it successfully joins the network, becomes a network-connected node, records the parent node, establishes a routing table to the central node, and initiates the network maintenance process. If the node obtains an invalid INVALID_TEI, it fails to join the network and attempts to join another network. If, during the network joining confirmation process, the node does not receive a NECM / NECGM with its own MAC address, and NETWORK_ENTRY_CONFIRMATION_WAIT_TIMER overflows, the node can attempt to join another network or re-initiate a request to that network.

2. The rapid networking method under a hybrid multiple access mode according to claim 1, characterized in that: In S11, the beacon frame's field information includes: network identifier, central node address, terminal device identifier, network formation flag, allow network entry flag, beacon timestamp, beacon period start time, beacon period length, beacon timeslot length, total number of beacons, total number of proxy nodes, and beacon allocation information; the network formation flag indicates that network formation is in progress, denoted as NETWORKING_IN_PROGRESS, and the allow network entry flag indicates that joining is allowed, denoted as ALLOWED_ENTRY.

3. The rapid networking method under a hybrid multiple access mode according to claim 2, characterized in that: In step S12, the central node receives and processes the network access request message NERM or the network access request summary message NERGM, specifically as follows: The central node receives NERM or NERGM and verifies the legitimacy of the requesting node within the network according to the whitelist. For nodes that pass verification, the central node assigns a TEI. For nodes that fail verification, the central node does not record it but assigns an invalid device identifier, denoted as INVALID_TEI, to indicate that the node does not belong to the network. The central node returns the assigned TEI to the node via the network entry confirmation message NECM and the network entry confirmation summary message NECGM along the original path. When the network state is NETWORKING_IN_PROGRESS, NECM and NECGM are sent as high-priority data frames.

4. The rapid networking method under a hybrid multiple access mode according to claim 3, characterized in that: In S12, when the central node is the parent node of the requesting node to join the network, the central node responds using NECGM. That is, when the central node receives multiple NERMs, it uses the network entry request aggregation algorithm of the already joined nodes to process them, and treats the multiple received NERMs as NERGMs for processing and response.

5. A rapid networking method under a hybrid multiple access mode according to claim 4, characterized in that: In step S14, the threshold for the number of nodes within the network is determined by the number of nodes in the whitelist by default. Upon completion of network formation, nodes already in the network are instructed not to execute the network entry request aggregation algorithm or maintain the message sending time limit mechanism. The entire network does not send or forward network entry-related messages with high-priority data frames. When a node not yet in the network receives a beacon frame with the network formation flag bit set to: When NETWORKING_COMPLETED is active, a network entry request can still be initiated. When the number of nodes in the network reaches the threshold, the network entry permission flag of the beacon frame will be set to disallowed, denoted as DENIED_ENTRY.

6. The rapid networking method under a hybrid multiple access mode according to claim 5, characterized in that: In step S21, when a node receives a NERM request, it determines whether to use the network entry request aggregation algorithm based on its own role attributes and network status. Specifically: When a node is a proxy node or the network status is NETWORKING_COMPLETED, the node directly forwards NERM along the path to the central node; otherwise, the node uses the network access request aggregation algorithm to generate NERGM for reporting. In the network access request aggregation algorithm, a network access request aggregation timer and an aggregation node number threshold are introduced. The network access request aggregation timer is denoted as NETWORK_ENTRY_REQUEST_GATHER_TIMER. When NETWORK_ENTRY_REQUEST_GATHER_TIMER overflows or the number of collected NERMs reaches the aggregation node number threshold, the NERGM construction is completed and the message reporting process begins. The timer duration is set to allow time for the central node to return to NECGM within this round of beacon cycle; The principle for setting the duration of a timer is expressed as follows: T reserved =α×RTT (2) in, It is the maximum value set for the timer duration, T. current It is the current network time as assessed by the node, T reserved This is the reserved time. RTT is the round-trip time to the central node as evaluated by the node, which is set based on the transmission and reception of beacon frames or historical values. α is the adjustment coefficient.

7. A fast networking method under a hybrid multiple access mode according to claim 6, characterized in that: Nodes already in the network periodically send maintenance messages, deciding whether to enable a maintenance message sending time limit mechanism based on their role and status. In this mechanism, the CSMA time slot is divided into two periods: a maintenance message sending limit and a maintenance message sending time. During the maintenance message sending time period, the node sends maintenance messages. The maintenance message sending limit segment consists of two parts: an absolute limit and a variable limit. The absolute limit is the minimum value of the maintenance message sending limit segment; the variable limit is determined by the node based on its own status. The node calculates the absolute limit time using the following formula: T R =T start +n total ×T beacon +T back_off (3) Among them, T R It is the end time of the absolute limit, n total It is the total number of beacon slots in the beacon frame, T. back_off The size depends on the parameter settings of the CSMA / CA algorithm used by the system, and the default value is the maximum value of backoff when sending messages; When T current ≤T R During this time, maintenance messages are queued in the sending queue; after the absolute restriction ends, the node determines whether the network access request aggregation algorithm has been started. If the node is currently performing network access request aggregation, the node's maintenance messages continue to queue.

8. A rapid networking method under a hybrid multiple access mode according to claim 7, characterized in that: In step S23, the time slot for the computation node to send beacon frames is expressed by the formula: T i =T statc +C i ×T beacon (4) Among them, T start This is the start time of the current beacon cycle, obtained from the beacon cycle start time field in the beacon frame. (C) i Node i queries the beacon allocation information in the beacon frame and finds its own TEI count value from the first record. beacon It is the value of the beacon slot length field in the beacon frame; when C i ≤n proxy At that time, node i is instructed to become the proxy node, n proxy This represents the total number of proxy nodes in the beacon frame; node i in T i It constantly sends its own beacon frames.

9. A rapid networking method under a hybrid multiple access mode according to claim 8, characterized in that: In step S31, after receiving the beacon frame, the non-network-connected node calculates the remaining time of the TDMA time slot. The calculation formula is as follows: in, C represents the listening duration of node j. i It is the count value of node i that sends beacon frames in the time slot allocation information.

10. A fast networking method under a hybrid multiple access mode according to claim 9, characterized in that: During the networking process of nodes not yet joining the network, after S31 ends, the nodes not yet joining the network enter S32 before the absolute restriction ends; while in S32, the nodes not yet joining the network can still receive beacon frames; the information of valid beacon frames is stored and used for nodes to change their target; after a node successfully joins the network, redundant beacon frame information is cleared; if a node fails to join the network, and there is other network information available, it does not need to repeat S31, but directly enters S32 to try to join a new network.

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