A tree network communication method and system based on frequency hopping

Abstract

The present invention relates to the field of wireless data transmission technology, and more specifically, to a tree network communication method and system based on frequency hopping. The method provided by the present invention mainly includes a concentrator, a routing node and a leaf node. A network is established through a concentrator, and a frequency hopping sequence is set. The frequency hopping sequence includes a broadcast frequency hopping sequence and a unicast frequency hopping sequence. The concentrator and the node communication of the network are carried out according to the frequency hopping sequence. Through the above method, each node in the network has a random frequency hopping sequence. In the case of multi-node networking communication, the anti-interference ability is strong and the communication stability is high. At the same time, it has a concise and efficient routing mechanism, named root-to-leaf routing, with small communication delay and high communication efficiency.

Description

Technical Field

[0001] This invention relates to the field of wireless data transmission technology, and more specifically, to a frequency-hopping-based tree network communication method and system. Background Technology

[0002] Sub-1G (or Sub-1GHz) is a radio communication technology that operates at frequencies below 1 GHz, typically in the 769-935 MHz, 315 MHz, and 468 MHz frequency ranges. Unlike 2.4G wireless communication technologies such as Wi-Fi and Bluetooth, the actual frequency band used by Sub-1GHz communication technology varies by region. North America and Australia use the 915 MHz band, while Europe uses the 868 MHz band. The 433 MHz band is available worldwide. Domestically, bands such as 433, 470, and 779 can be used. Compared to the 2.4GHz band, Sub-1G offers superior communication range compared to Wi-Fi and Bluetooth in wireless IoT applications.

[0003] Frequency-hopping (FHSS) is one of the most commonly used spread spectrum techniques in wireless communication. It involves discretely changing the carrier frequency of the wireless transmission signal between the transmitting and receiving devices according to a predetermined algorithm or rule. In other words, the carrier frequency used in wireless communication is randomly changed under the control of a pseudo-random change code. Based on this technique, in a wireless network system, wireless communication between nodes does not occur on a fixed channel; instead, the channel switches between random sequences.

[0004] In current wireless applications, most applications require communication between a central node and various nodes in the network, but the stability and anti-interference capabilities of this communication need to be improved. Summary of the Invention

[0005] The purpose of this invention is to provide a frequency-hopping-based tree network communication method and system to solve the problems existing in the prior art.

[0006] This invention is achieved through the following technical solution:

[0007] A frequency-hopping-based tree network communication method includes a concentrator, routing nodes, and leaf nodes;

[0008] A network is established through a concentrator, and a frequency hopping sequence is set, including a broadcast frequency hopping sequence and a unicast frequency hopping sequence. The concentrator and the network nodes communicate according to the frequency hopping sequence.

[0009] Before powering on and connecting to the network, routing nodes and leaf nodes periodically broadcast network connection requests on broadcast channel 0.

[0010] When the concentrator switches to broadcast channel 0 and receives a network access request from a routing node or leaf node, the concentrator assigns a unicast frequency hopping sequence to the node to be connected to the network and performs time synchronization. The node to be connected to the network then begins broadcasting and unicast frequency hopping.

[0011] The concentrator sends the unicast frequency hopping sequence and the unicast frequency hopping sequence of the already joined nodes to the nodes to be joined, and at the same time exchanges network parameters to complete the network access;

[0012] All network nodes after joining the network perform frequency hopping according to a unified timeline. When a node receives a routing path broadcast packet sent by the concentrator, it performs time calibration and frequency hopping synchronization.

[0013] When the concentrator communicates with the target node in the network via unicast, it queries the target node's unicast frequency hopping sequence before sending data, switches the channel to the unicast channel that the target node is listening to, and switches the concentrator to its own frequency hopping sequence to receive data after sending the data.

[0014] Preferably, the concentrator establishes the network by:

[0015] Establish a fixed channel network or a frequency hopping channel network;

[0016] When establishing a fixed-channel network, scan the current environment and select the best channel to establish the network.

[0017] When a frequency hopping channel network is established, the concentrator randomly generates a frequency hopping sequence and assigns it to a node. The node then communicates according to the frequency hopping sequence.

[0018] Preferred options also include;

[0019] After the concentrator establishes the network, it broadcasts broadcast frames at a certain period. After receiving the broadcast frames, the nodes obtain the optimal communication path from the concentrator.

[0020] If a routing node in the network switches, all nodes in the network will dynamically switch to the best path of the concentrator after receiving the broadcast frame sent by the concentrator.

[0021] The broadcast frame includes a timestamp. After receiving the broadcast frame, all nodes in the network use the timestamp to calibrate and synchronize their clocks.

[0022] Preferred options also include:

[0023] The concentrator broadcasts a routing path broadcast packet to the network. The routing nodes in the network simultaneously receive the routing path broadcast packet and begin to forward it in an orderly manner.

[0024] The ordered forwarding includes setting a delay interval (delay) to obtain the forwarding time for each routing node:

[0025]

[0026] In the formula, For the first Forwarding time of each routing node It is determined by the order in which the router enters the network.

[0027] Preferred options also include:

[0028] After receiving route path broadcast packets forwarded by other route nodes, the concentrator and routing nodes store the forwarded route node information in the neighbor table;

[0029] Once all routing nodes have forwarded the route path broadcast packets sent by the concentrator, each node obtains its own route depth.

[0030] Preferred options also include:

[0031] The concentrator broadcasts routing path broadcast frames, and the routing nodes forward these frames in ascending order of their joining order.

[0032] After forwarding is completed, the routing node obtains several paths to the concentrator and saves them to its own routing table. During communication, it selects the path with the best link quality indicator from the routing table.

[0033] Secondly, the present invention provides a frequency-hopping-based tree network communication system, comprising:

[0034] The network establishment module is configured to include a concentrator, routing nodes, and leaf nodes: the network is established through the concentrator, and a frequency hopping sequence is set, which includes a broadcast frequency hopping sequence and a unicast frequency hopping sequence. The concentrator and the network nodes communicate according to the frequency hopping sequence. Before powering on and joining the network, the routing nodes and leaf nodes periodically broadcast a network joining request on broadcast channel 0.

[0035] The network entry module is configured such that when the concentrator switches to broadcast channel 0 and receives a network entry request from a routing node or leaf node, the concentrator allocates a unicast frequency hopping sequence to the node to be joined and performs time synchronization. The node to be joined then begins broadcasting and unicast frequency hopping, obtains the concentrator's unicast frequency hopping sequence and the unicast frequency hopping sequences of already joined nodes, and exchanges network parameters to complete the network entry. All network nodes after joining the network perform frequency hopping according to a unified time axis, and perform time calibration and synchronization when receiving a broadcast packet of a routing path. When the concentrator and a target node in the network perform unicast communication, the concentrator queries the target node's unicast frequency hopping sequence before sending data, switches the channel to the unicast channel that the target node is listening to, and switches the concentrator to the concentrator's frequency hopping sequence to receive data after sending the data.

[0036] The main control module is connected to the network establishment module and the network entry module, and is used to execute the above-described frequency-hopping-based tree network communication method.

[0037] Thirdly, the present invention also provides an electronic device, including a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that the processor, when executing the computer program, implements the above-described frequency-hopping-based tree network communication method.

[0038] Fourthly, the present invention also provides a computer-readable storage medium storing a computer program that, when executed by a processor, implements the above-described frequency-hopping-based tree network communication method.

[0039] The technical solution of the present invention has at least the following advantages and beneficial effects:

[0040] The method provided by this invention mainly includes a concentrator, routing nodes, and leaf nodes. A network is established through the concentrator, and a frequency hopping sequence is set. This frequency hopping sequence includes broadcast frequency hopping sequences and unicast frequency hopping sequences. Communication between the concentrator and network nodes is based on the frequency hopping sequence. Through this method, each node in the network has a random frequency hopping sequence. In multi-node network communication, it has strong anti-interference capabilities and high communication stability. It also possesses a simple and efficient routing mechanism, named root-to-leaf routing, with low communication latency and high communication efficiency. Attached Figure Description

[0041] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present invention and should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0042] Figure 1 This is a schematic diagram of the network topology of the present invention;

[0043] Figure 2 This is a schematic diagram of the frequency hopping process of the present invention;

[0044] Figure 3 This is a schematic diagram of the frequency hopping communication process for network access in this invention;

[0045] Figure 4 This is a schematic diagram of the tree-path broadcast process of the present invention;

[0046] Figure 5 This is a schematic diagram of the route discovery process of the present invention. Detailed Implementation

[0047] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. The components of the embodiments of the present invention described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0048] The terms "first," "second," etc., used in the specification, claims, and accompanying drawings of this application are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. The naming or numbering of steps in this application does not imply that the steps in the method flow must be executed in the chronological / logical order indicated by the naming or numbering. The execution order of named or numbered process steps can be changed according to the desired technical objective, as long as the same or similar technical effect is achieved.

[0049] Please refer to Figures 1-5 This invention provides a frequency-hopping-based tree network communication method, including a concentrator, routing nodes, and leaf nodes;

[0050] In this network topology, the Concentrator (CT), Router Node (RN), and Leaf Node (LN) are abbreviated as CT, RN, and LN, respectively. See the appendix for the detailed network topology. Figure 1The CT (Tree Chord) is the network's core, responsible for establishing and managing the network. It assigns random frequency hopping sequences to each node joining the network and periodically broadcasts root-to-leaf tree routing path packets (tree-path). The RN (Relay Node) functions as a relay, forwarding network and application data, extending the network's communication distance, and is a full-featured device that also supports reporting collected data and sending control data. The LN (Local Node) is the network's terminal, reporting collected data and sending control data, and supports low power consumption. This network communication system has two main characteristics: a simple and efficient root-to-leaf routing mechanism, and each node possessing its own independent frequency hopping sequence, providing strong anti-interference capabilities.

[0051] In a network, routing nodes act like branches of a tree trunk. They are full-featured devices that do not support low power consumption, possess data forwarding capabilities, and can also collect and report data or send control data to the CT (Transmitter). After joining the network, the RN (Receiver Node) obtains its unicast frequency hopping sequence, network PANID, network communication address, and other information from the CT. The RN's network communication address, named RN-addr, also represents its network entry order and ranges from 0x01 to 0x80.

[0052] Leaf nodes in a network, similar to leaves in a tree-like network, support low power consumption and primarily perform data acquisition and reporting or transmit control data to the CT. After joining the network, an LN obtains information such as the unicast frequency hopping sequence, network communication address, and network PANID from the CT. The LN's network communication address is defined as a 16-bit range of 0x0081-0xfffe.

[0053] The network communication addresses of all nodes in the network are explained below. 0x00- represents the network communication address of the CT (Cybernetic Node), which is always 0. 0x01-0x80 represent the network communication addresses of the RN (Receptive Node), and also indicate the order in which the RNs joined the network. 0x0081-0xfffe represent the network communication addresses of the LN (Literate Node), and also represent the order in which the LNs joined the network. The first LN to join the network has an address of 0x81, the second has 0x82, and so on. See the appendix for details. Figure 3 The network access process.

[0054] S101: A network is established through a concentrator, and a frequency hopping sequence is set. The frequency hopping sequence includes a broadcast frequency hopping sequence and a unicast frequency hopping sequence. The concentrator and the network nodes communicate according to the frequency hopping sequence.

[0055] The primary function of the CT (Tree-Based Network) is to establish and manage networks. In a tree-structured network, it acts as the root. The network it establishes can be either a fixed-channel network or a frequency-hopping channel network. If establishing a fixed-channel network, the CT scans the environment before establishing the network and selects the optimal (interference-free) channel. If establishing a frequency-hopping channel network, when a node joins the network, the CT randomly generates a frequency-hopping sequence and assigns it to the node. Subsequent communication with this node follows this sequence. After establishing the network, the CT periodically broadcasts the tree path to maintain communication between the CT and each node, while also maintaining the network's heartbeat function. Nodes detect whether the CT is online, enabling self-organizing and self-healing network capabilities.

[0056] S102: Before powering on and joining the network, routing nodes and leaf nodes periodically broadcast network joining requests on broadcast channel 0 (CH0);

[0057] S103: When the concentrator switches to broadcast channel 0 (CH0) and receives a network access request from a routing node or leaf node, the concentrator allocates a unicast frequency hopping sequence to the node to be connected to the network and performs time synchronization. The node to be connected to the network then begins broadcasting and unicast frequency hopping.

[0058] The CT and other nodes in the network communicate according to a prescribed frequency hopping sequence. Before joining the network, the channel list parameters of all nodes (CT, RN, LN) must be completely consistent. The channel list specifies the starting channel, channel interval, and ending channel, so that they remain on the same frequency during frequency hopping communication. Of course, the channel list parameters can be configured, but after configuration, the channel list parameters of all nodes must be consistent.

[0059] Frequency hopping sequences include broadcast frequency hopping sequences and unicast frequency hopping sequences. Broadcast frequency hopping sequences follow the order configured in the channel list (CH0, CH1, CH2, CH3, CH4, etc.). For unicast frequency hopping sequences, each node in the network has its own sequence. After establishing the network, the CT (Channel Center) randomly generates a unicast frequency hopping sequence for itself. When a node joins the network, the CT randomly generates a unicast frequency hopping sequence (CH8, CH4, CH12, CH5, CH1, etc.) for that node and sends it to the node. Simultaneously, it also sends the unicast sequences of already joined nodes and the CT to nodes joining the network. Therefore, every node in the network knows the unicast frequency hopping sequences of other nodes.

[0060] During network communication, before sending data to the target node, the source node queries the target node's frequency hopping sequence and switches its PHY channel to the target node's currently listening channel to send data. The target node can then successfully receive the data. (See Appendix for details on frequency hopping in network communication.) Figure 2 .like Figure 3As shown, the broadcast frequency hopping sequence is fixed, while the unicast frequency hopping sequence is allocated during the network access process.

[0061] S104: Obtain the unicast frequency hopping sequence of the concentrator and the unicast frequency hopping sequence of the nodes that have already joined the network, and send them to the nodes to be joined the network. At the same time, exchange network parameters to complete the network entry.

[0062] S105: All network nodes after joining the network will hop frequencies according to a unified timeline. When a routing path broadcast packet is received, time calibration and synchronization will be performed.

[0063] S106: When the concentrator and the target node in the network are conducting unicast communication, the concentrator queries the target node's unicast frequency hopping sequence before sending data, switches the channel to the unicast channel that the target node is listening to, and switches the concentrator to the concentrator's frequency hopping sequence to receive data after sending the data.

[0064] When a node unicasts data to other nodes or unicasts data to a CT, it follows the same method as the previous step: first, it switches to the target node's frequency hopping channel, and after sending the data, it switches back to its own frequency hopping sequence.

[0065] In one exemplary embodiment of the present invention, the concentrator establishes a network comprising:

[0066] Establish a fixed channel network or a frequency hopping channel network; when establishing a fixed channel network, scan the current environment and select the best channel to establish the network; when establishing a frequency hopping channel network, the concentrator randomly generates a frequency hopping sequence and assigns it to the node, and the node communicates according to the frequency hopping sequence.

[0067] An exemplary embodiment of the present invention further includes;

[0068] After the concentrator establishes the network, it broadcasts broadcast frames at a certain period. After receiving the broadcast frame, the node obtains the best communication path of the concentrator. When a routing node in the network switches, all nodes in the network receive the broadcast frame sent by the concentrator and dynamically switch to the best path of the concentrator. The broadcast frame includes a timestamp. After receiving the broadcast frame, all nodes in the network use the timestamp to calibrate and synchronize the clock of the current node.

[0069] An exemplary embodiment of the present invention further includes:

[0070] The concentrator broadcasts a routing path broadcast packet to the network. Routing nodes in the network receive the routing path broadcast packet and begin orderly forwarding it. Ordered forwarding includes setting a delay interval (delay) to obtain the forwarding time for each routing node.

[0071]

[0072] In the formula, For the first Forwarding time of each routing node The order in which routing nodes join the network determines the order.

[0073] In root-to-leaf routing, the concentrator module (CT) broadcasts a tree-path frame to the network. RNs in the network simultaneously receive the tree-path and begin orderly forwarding. RN-1 (RN-addr = 1 indicates the first RN to join the network) forwards immediately without delay. RN-2 forwards with a delay of 1 * delay, RN-3 forwards with a delay of 2 * delay, and so on, until finally RN-m forwards with a delay of (m-1) * delay. The baseline delay for RN forwarding is related to the air speed of wireless communication; the higher the air speed, the smaller the delay.

[0074] An exemplary embodiment of the present invention further includes:

[0075] After receiving route path broadcast packets forwarded by other route nodes, the concentrator and route nodes store them in the neighbor table; after all route nodes have forwarded the route path broadcast packets, all route nodes also obtain their own route depth.

[0076] The CT receives the tree-path forwarded by the RN and stores the forwarded RN in the neighbor table. Similarly, the RN receives the tree-path forwarded by other RNs and stores the forwarded RN in the neighbor table. At this point, all RNs and CTs in the network have obtained their own neighbor tables.

[0077] After the CT broadcasts the tree-path frame and all RNs forward it, each node will receive its own routing depth (or simply depth). The CT's depth is 0. If an RN successfully receives the tree-path broadcast by the CT, then the depth of that range of RNs is 1, named RN-depth1. RNs that receive the tree-path forwarded by RN-depth1 are named RN-depth2, and so on. All nodes in the network broadcast the received tree-path frame only once, refer to... Figure 4 If a broadcast has already been made, and a broadcast frame with the same sequence number is received again, the broadcast will not be made again.

[0078] An exemplary embodiment of the present invention further includes:

[0079] The concentrator broadcasts routing path broadcast frames, and routing nodes forward them in ascending order of joining the network, i.e., the first to join is forwarded first. After forwarding, the routing nodes obtain several paths to the concentrator and save them to their own routing tables. During communication, they select the path with the best link quality indicator from the routing table.

[0080] The process of route discovery for all nodes involves the CT sending a tree-path broadcast frame. The RN node with a route depth of 1 begins broadcasting and forwarding, followed by the RN node with a route depth of 2, and so on. Once all RN nodes have finished broadcasting and forwarding, as shown in the attached diagram... Figure 4 The RN node shown will obtain multiple paths to CT and save them to its own routing table. During communication, it will select the LQI-optimal path from the routing table. CT obtains the path from each node, as shown in the attached table. Figure 4 As shown, after the RN with a routing depth of 2 obtains the best path, it will unicast its own path and its child nodes to the CT (the RN with a routing depth of 1 is the CT's neighbor node and knows its path). Then the RN node with a routing depth of 3 starts to reply. After the CT receives the reply, it knows the path to each node and stores it in its own routing table.

[0081] To further illustrate the method provided by this invention, a specific example is given below:

[0082] Step 1: The CT establishes the network, and the RN and LN join the network to establish frequency hopping communication, as follows: Figure 3 As shown:

[0083] When the CT is powered on, a network is established. The broadcast frequency hopping sequence switches on the channel in the order CH0, CH1, CH2... in the channel list. At the same time, a unicast frequency hopping sequence is randomly assigned, such as CH8, CH2, CH5, CH9...

[0084] The CT broadcast frequency hopping sequence and unicast frequency hopping sequence have been established, as shown in the attached figure. Figure 2 Frequency hopping is performed as shown, and the following steps are required to achieve it:

[0085] Broadcast settings include broadcast dwell time and broadcast interval; unicast settings include unicast dwell time.

[0086] The timeline starts from synchronization time 0. CT initially stays on broadcast channel CH0 for data transmission and reception monitoring. After the broadcast dwell time, it switches to unicast channel CH8 for transmission and reception. When the next broadcast channel CH1 arrives, it switches to broadcast channel CH1 for transmission and reception. After the broadcast dwell time, it switches to unicast channel CH2 for transmission and reception, and so on.

[0087] When an RN (or LN) node powers on, it is fixed on the CH0 channel before joining the network and periodically broadcasts a network entry request, because at this time the node has not yet obtained unicast frequency hopping information.

[0088] When the CT switches frequency hopping to the broadcast CH0 channel and receives a network access request from an RN (or LN) node, the CT assigns a unicast frequency hopping sequence to the node and simultaneously performs time synchronization. The node then begins to follow the assigned sequence. Figure 2 Start broadcasting and unicast frequency hopping.

[0089] The CT sends its own unicast frequency hopping sequence and the unicast frequency hopping sequences of the already joined nodes to the new nodes, while exchanging other network parameters such as network PANID, network key, and network address to complete the network entry.

[0090] After joining the network, each node in the network will know the unicast frequency hopping sequence and broadcast frequency hopping sequence of all other nodes, and will perform frequency hopping according to the same time axis. Whenever a broadcast packet is received, time calibration and synchronization will be performed.

[0091] When a CT communicates unicastly with a node in the network, the CT queries the target node's unicast sequence before sending data and switches its channel to the unicast channel that the target node is listening to (if the target node is listening to a broadcast channel at this time, the CT will wait until the target node switches to unicast listening before switching channels). After sending the data, the CT switches to its own frequency hopping sequence to receive data.

[0092] Similarly, when a node unicasts data to other nodes or unicasts data to the CT, following the method in step 7, it first switches to the target node's frequency hopping channel, and after sending the data, it switches back to its own frequency hopping sequence.

[0093] Step 2: After all nodes have completed network formation, establish routing paths (route discovery). Specific implementation steps are as follows: Figure 4 , Figure 5 As shown:

[0094] During network operation, CT broadcasts tree-path frames at regular intervals to dynamically maintain network routes, and the route paths can be automatically repaired.

[0095] CT broadcasts a frame of tree-path.

[0096] RN1, RN2, and RN3 are within the effective communication range of CT, and can receive the broadcast tree-path of CT.

[0097] RN1 broadcasts to the tree-path, RN2 broadcasts with a delay of 1*delay, and RN3 broadcasts with a delay of 2*delay. This avoids broadcasting storms caused by simultaneous broadcasting. Electromagnetic waves travel very fast, so the delay is very small.

[0098] RN4, RN5, and RN6 are within the effective communication distance range of RN1, RN2, and RN3, and can receive broadcast tree-paths from RN1, RN2, and RN3.

[0099] RN4 broadcasts the tree-path, RN5 broadcasts with a delay of 4*delay, and RN6 broadcasts with a delay of 5*delay. This avoids broadcasting storms caused by simultaneous broadcasting. Electromagnetic waves travel very fast, so the delay is very small.

[0100] Once all nodes have broadcast and forwarded the tree-path, each node stores multiple paths to the CT in its routing table, selecting the path with the best LQI value as the communication path and using the others as backup paths. This ensures that all nodes know the path to the CT.

[0101] CT obtains the paths of RN and LN.

[0102] RN nodes with a routing depth exceeding depth1, after obtaining the best path for the first time, send the best path and their child nodes LN to CT via unicast, in the order of RN4, RN5, RN6.

[0103] CT is a periodic broadcast tree-path. The broadcast period can be set. RN nodes with a routing depth greater than depth1 will only send CT information via unicast when the optimal path changes or when their child LN changes.

[0104] CT stands for periodic broadcast tree-path, which updates the network's routing path at regular intervals. Therefore, when a Reactor (RN) moves or leaves the network, the network's routing path can be automatically repaired.

[0105] CT saves the path of each RN node and LN node in the source routing table. During each communication, there is no need to dynamically find the path of the node. Data can be sent directly, which improves communication efficiency.

[0106] Secondly, the present invention provides a frequency-hopping-based tree network communication system, comprising:

[0107] The network establishment module is configured to include a concentrator, routing nodes, and leaf nodes: the concentrator establishes the network and sets a frequency hopping sequence, which includes a broadcast frequency hopping sequence and a unicast frequency hopping sequence; the concentrator and network nodes communicate according to the frequency hopping sequence; the routing nodes and leaf nodes periodically broadcast network access requests on the channel before powering on and joining the network.

[0108] The network entry module is configured to, when the concentrator switches to the broadcast channel and receives a network entry request from a routing node or leaf node, allocate a unicast frequency hopping sequence to the node to be joined and perform time synchronization. The node to be joined then begins broadcasting and unicast frequency hopping. The module acquires the unicast frequency hopping sequence of the concentrator and the unicast frequency hopping sequences of already joined nodes and sends them to the node to be joined, while exchanging network parameters to complete the network entry. All network nodes after joining the network perform frequency hopping according to a unified time axis. When a broadcast packet of a routing path is received, time calibration and synchronization are performed. When the concentrator and a target node in the network are conducting unicast communication, the module queries the unicast frequency hopping sequence of the target node before the concentrator sends data, switches the channel to the unicast channel that the target node is listening to, and switches the concentrator to the concentrator's frequency hopping sequence to receive data after sending the data.

[0109] The main control module is connected to the network establishment module and the network entry module, and is used to execute the above-described frequency-hopping-based tree network communication method.

[0110] Furthermore, the functional units in the various embodiments of the present invention can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. The integrated unit can be implemented in hardware or as a software functional unit.

[0111] If the integrated unit is implemented as a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. This computer software product, stored in a storage medium, includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods of the various embodiments of the present invention. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

[0112] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A tree network communication method based on frequency hopping, characterized in that: Includes concentrators, routing nodes, and leaf nodes; Establishing a network through a concentrator, setting a frequency hopping sequence, wherein the frequency hopping sequence includes a broadcast frequency hopping sequence and a unicast frequency hopping sequence, and the concentrator and the nodes of the network communicate according to the frequency hopping sequence; Before the routing nodes and leaf nodes are powered on and connected to the network, they periodically broadcast network access requests on broadcast channel 0; When the concentrator switches to broadcast channel 0 by frequency hopping and receives a network access request from a routing node or a leaf node, the concentrator allocates a unicast frequency hopping sequence to the node to be networked, performs time synchronization at the same time, and the node to be networked starts broadcasting and unicast frequency hopping; The concentrator sends the unicast frequency hopping sequence and the unicast frequency hopping sequence of the node that has already joined the network to the node to be joined, and exchanges network parameters at the same time to complete the network joining; All network nodes that have joined the network perform frequency hopping according to a unified time axis. When receiving the routing path broadcast packet sent by the concentrator, the node performs time calibration and frequency hopping synchronization; When the concentrator and the target node in the network perform unicast communication, the concentrator queries the unicast frequency hopping sequence of the target node before sending data, switches the channel to the unicast channel that the target node is monitoring, and after sending the data, switches the concentrator to the frequency hopping sequence of the concentrator to receive data monitoring; The concentrator establishes a network including: Establish a fixed channel network or a frequency hopping channel network; When establishing a fixed channel network, scan the current environment and select the best channel to establish the network; When a frequency hopping channel network is established, the concentrator randomly generates a frequency hopping sequence and assigns it to the node, and the node communicates according to the frequency hopping sequence.

2. A tree network communication method based on frequency hopping according to claim 1, characterized in that: Also includes; After the concentrator establishes the network, it broadcasts broadcast frames at a certain period. After receiving the broadcast frames, the nodes obtain the best communication path of the concentrator. If a routing node in the network switches, all nodes in the network will dynamically switch to the best path of the concentrator after receiving the broadcast frame sent by the concentrator; The broadcast frame includes a timestamp. After receiving the broadcast frame, all nodes in the network calibrate and synchronize the clock of the current node through the timestamp.

3. A frequency hopping based tree network communication method according to claim 2, characterized in that: Also includes: The concentrator broadcasts a routing path broadcast packet to the network. The routing nodes in the network receive the routing path broadcast packet at the same time and start forwarding it in order. The orderly forwarding includes setting a delay interval delay to obtain a forwarding time for each routing node: In the formula, For the The forwarding time of a routing node, It is determined by the order in which the routes enter the network.

4. A frequency hopping based tree network communication method according to claim 3, characterized in that: Also includes: After receiving the routing path broadcast packet forwarded by other routing nodes, the concentrator and routing node store the forwarded routing node information in the neighbor table; When all routing nodes have forwarded the routing path broadcast packets sent by the concentrator, all nodes obtain their own routing depth.

5. A frequency hopping based tree network communication method according to claim 4, characterized in that: Also includes: The concentrator broadcasts the routing path broadcast frame, and the routing nodes forward the broadcast in ascending order according to the order in which they join the network. After forwarding is completed, the routing node obtains several paths to the concentrator and saves them in the routing table of each routing node. During communication, a path with the best link quality indicator is selected from the routing table.

6. A tree network communication system based on frequency hopping, characterized in that: include: The network establishment module is configured to include a concentrator, a routing node and a leaf node: a network is established through the concentrator, a frequency hopping sequence is set, and the frequency hopping sequence includes a broadcast frequency hopping sequence and a unicast frequency hopping sequence, and the concentrator and the node communication of the network are performed according to the frequency hopping sequence; before the routing node and the leaf node are powered on and connected to the network, the network access request is periodically broadcast on the broadcast channel 0; Network access module: when the concentrator switches to broadcast channel 0 by frequency hopping and receives a network access request from a routing node or a leaf node, the concentrator allocates a unicast frequency hopping sequence to the node to be networked, performs time synchronization at the same time, and the node to be networked starts broadcasting and unicast frequency hopping; The concentrator sends the unicast frequency hopping sequence of the node that has joined the network to the node to be joined, and exchanges network parameters at the same time to complete the network joining; all network nodes that have joined the network perform frequency hopping according to the unified time axis, and perform time calibration and synchronization when receiving the routing path broadcast packet; when the concentrator and the target node in the network perform unicast communication, the concentrator queries the unicast frequency hopping sequence of the target node before sending data, switches the channel to the unicast channel that the target node is monitoring, and after sending the data, switches the concentrator to the concentrator's frequency hopping sequence to receive data monitoring; A main control module, the main control module is connected to the network establishment module and the network access module, and is used to execute a tree network communication method based on frequency hopping as described in any one of claims 1-5.

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