Road service performance monitoring data acquisition method and system based on LoRa Mesh

Abstract

The invention discloses a road service performance monitoring data acquisition method and system based on LoRa Mesh in the field of road service performance monitoring. LoRa module configuration methods such as a LoRa acquisition node, a LoRa routing node and a LoRa concentrator and implementation of a LoRa Mesh routing protocol are explained. The acquisition system has the functions of network self-healing, ad hoc network, multi-hop transmission and the like, supports sensor data with small data volume and low acquisition frequency requirements such as temperature and humidity, wind speed and wind direction, inclination angle and the like, and sends the data to a cloud platform by using a wireless transmission network. By reasonably deploying the Lora routing nodes, the monitoring system can perform stable data transmission in an environment with more obstacle shielding, meanwhile, the system has a data transmission link automatic switching function, a new transmission channel can be quickly constructed when an original link breaks down, normal transmission of data is ensured, and the data transmission efficiency is improved. The problems that a traditional wired sensing monitoring system is high in wiring cost, poor in flexibility and the like can be effectively solved.

Description

Technical Field

[0001] The present invention relates to the technical field of highway service performance monitoring, and in particular to a highway service performance monitoring data collection method and system based on LoRa Mesh. Background Art

[0002] LoRa (Long Range) is a LPWAN (Low Power Wide Area Network) technology released by Semech. At present, the LoRa communication network is mainly carried on several Sub-1Ghz frequencies such as 470~510Mhz and 900Mhz. This technology is used in low-power industrial Internet of Things, which can realize node networking, node target data monitoring and data return synchronization. This technology has the characteristics of relatively fixed node positions and networking modes, long transmission distance, low transmission rate and small data volume.

[0003] Wireless Mesh Network is a wireless network based on mesh topology, and its core features include self-configuration, self-healing and high bandwidth. This technology realizes a new architecture of wireless local area network by building a mesh structure composed of multiple nodes. The core feature of Mesh self-organizing network technology is self-organization ability, that is, nodes in the network can automatically discover other nodes and establish connections without human intervention. In addition, data can be transmitted through multiple intermediate nodes, reducing the probability of data packet loss and delay, and effectively expanding the network coverage, improving network reliability and fault tolerance. In the case of node failure or new node joining, Mesh network can automatically reorganize the network structure to maintain the stability and efficiency of the network.

[0004] During the use of highway infrastructure, the traditional data transmission method uses wired connections. In the actual installation and use process, due to the long distance of the highway, the cable cost is high during the use of wired transmission. At the same time, wired cables are at risk of being damaged by rain and other environmental factors. Therefore, it is more efficient and economical to use wireless transmission to transmit information.

[0005] The Chinese patent with announcement number CN108882250B discloses a LoRa-mesh dual-mode communication device, which belongs to the field of wireless communication technology. It includes a housing and a control unit, the control unit is connected to a positioning module, a Bluetooth module, an FM frequency modulation module, a LoRa-mesh dual-mode communication module and a battery module, and the positioning module, Bluetooth module, FM frequency modulation module and LoRa-mesh dual-mode communication module are all connected to corresponding antennas. The present invention can interact with the user's mobile phone through the Bluetooth module. In addition, in areas with insufficient signal coverage, users can quickly network through this device to provide the most flexible way to achieve communication between mobile users, fixed base stations, and mobile base station devices.

[0006] However, the above-mentioned disclosed solutions have the following shortcomings: the above-mentioned devices communicate through the LoRa data protocol, but the above-mentioned devices do not have the ability to send and verify RREQ messages in actual use. Therefore, in a multi-node use environment, the above-mentioned devices have the situation that data is repeatedly sent between nodes or lost during the transmission process between nodes. The wired sensor data collection method has a series of problems such as complex wiring, cumbersome installation, low intelligence, and high cost. For this reason, the application of wireless sensor networks in the field of highway service performance monitoring is becoming a current research hotspot. Wireless sensor networks collect information about the physical environment through advanced sensing technology at the bottom layer, convert it into digital information at the sensor node, and transmit it to the network through wireless communication technology, giving full play to its advantages of low power consumption, low cost, easy deployment, and strong performance. Among the many wireless communication technologies, the more representative ones are NB-IoT, ZigBee, Wi-Fi, LoRa, etc. Among them, NB-IoT relies on operator base stations and is limited in application in remote areas with poor signal coverage; ZigBee has high power consumption and short transmission distance, and is more suitable for application scenarios such as smart home interconnection; Wi-Fi is difficult to use in fields such as tunnel health monitoring due to its small transmission range and high power consumption. As a low-power wireless communication technology, LoRa has the advantages of large network capacity and low cost, and the transmission distance can reach several thousand meters in unobstructed areas. Research on the application of LoRa communication technology in bridge and tunnel monitoring systems has made some progress, but the above research results mainly focus on the realization of LoRa's point-to-point communication or star networking functions. The designed network system does not have the self-organizing network function, and the data transmission reliability needs to be improved. Summary of the invention

[0007] The purpose of this section is to summarize some aspects of the embodiments of the present invention and briefly introduce some preferred embodiments. Some simplifications or omissions may be made in this section and the specification abstract and the invention title of the present invention to avoid blurring the purpose of this section, the specification abstract and the invention title, and such simplifications or omissions cannot be used to limit the scope of the present invention.

[0008] The purpose of the present invention is to address the technical problems existing in the background technology. The present invention proposes a data collection method and system for monitoring the service performance of infrastructure based on LoRa Mesh. The present invention can effectively improve the stability of wireless data transmission. The present invention proposes a data collection method for highway service performance monitoring sensors based on LoRa Mesh, using LoRa wireless communication technology to collect monitoring sensor data and transmit it to the cloud platform. The data collection system has functions such as network self-healing, self-organizing network, and multi-hop transmission, which can effectively solve various problems of traditional wired sensor monitoring systems. The method divides the monitoring sensor data collection system into monitoring sensors, LoRa collection nodes, LoRa routing nodes, LoRa concentrators, cloud gateways, and integrated management cloud platforms. Among them, the routing protocol is integrated inside the LoRa routing node to realize the multi-hop routing function, which can provide a sensor networking solution with the characteristics of high reliability, flexible expansion and redundancy.

[0009] The present invention proposes a highway service performance monitoring data collection method and system based on LoRa Mesh, a LoRa module configuration step, and configures the core parameters of the LoRa collection node, LoRa routing node, and LoRa concentrator node through the LoRa AT command, including wireless rate, transmission power, device address, serial port baud rate and other information;

[0010] Cloud platform configuration steps: configure the monitoring sensor Modbus device address, value type, polling cycle and other information in the cloud platform software;

[0011] Node transmission step: the monitoring sensor information is transmitted to the Lora collection node through the Modbus protocol. The Lora collection node repackages the Modbus protocol data and transmits the data to the nearest Lora routing node through the Lora protocol.

[0012] Information upload step: After receiving the information, the Lora routing node sends a RREQ message to initiate a routing request, and sets the destination address to the address of the Lora concentrator node. When the intermediate node receives the RREQ message, it determines whether the current node is the destination node. If it is the destination node, it replies with the RREP message and the process ends. If it is not the destination node, it determines whether there is a route to the destination node. If so, it sends a RREP message. If not, it caches the RREQ message and forwards it, and the process ends. When the intermediate node receives the RREP message, it first updates the route to the destination node, the destination node predecessor list and other information, and then determines whether the node is the source node. If so, it uses the newly created routing link to send the cached data, otherwise it sends a unicast RREP message to the next hop of the route, and the process ends. When the intermediate node receives the RERR message, it deletes the faulty link and updates the routing table, and the process ends.

[0013] In the information aggregation step, the final data is aggregated to the Lora concentrator node, which caches and compresses the data and sends it to the 4G cloud network through the serial port transparent transmission method, and further sends it to the cloud platform;

[0014] In the data analysis step, the cloud platform software parses the received monitoring sensor data and displays, stores and analyzes it in real time.

[0015] By adopting the above-mentioned technical scheme, this scheme can achieve the effect of adaptive information transmission of this method by sending RREQ messages, so that when the system corresponding to this method installs nodes, it is not necessary to install nodes of different types in sequence in a targeted manner, but a series of identical nodes are installed at the same time in a certain area to form a network. Within the network, the information will find the appropriate and shortest transmission line by itself according to the target identification information, thereby reducing the difficulty of system installation.

[0016] Preferably, the Lora module configuration step, when performing module setting in an actual road environment, turns on the Lora module, adjusts the spacing between the Lora modules by moving, detects the strength of the signal transmitted between the current Lora module and the surrounding Lora modules in real time, and records the spacing between the current Lora modules when the adjacent Lora modules move to the critical value of the strong signal range, and then installs the Lora modules at equal spacings at the current spacing size.

[0017] By adopting the above technical solution, this solution can determine the optimal distribution spacing of the Lora modules in the current environment by detecting the signal strength of adjacent Lora modules, thereby ensuring that the use of Lora modules is minimized while information can be transmitted stably, thereby reducing the cost of this method when in use.

[0018] Preferably, the cloud platform configuration step is performed by marking and connecting a plurality of LoRa acquisition nodes and LoRa routing nodes, so that different locations of the highway can be managed and controlled according to the marked LoRa acquisition nodes and LoRa routing nodes on the cloud platform page, and by using geographic tags on the cloud platform instead of the model codes used by the LoRa acquisition nodes and LoRa routing nodes, the LoRa acquisition nodes and LoRa routing nodes in different areas can be quickly located during the use of the cloud platform.

[0019] By adopting the above technical solution, this solution manages several LoRa collection nodes and LoRa routing nodes through a cloud platform, which can reduce the difficulty of users to operate the LoRa collection nodes and LoRa routing nodes, and can display the environmental parameters of corresponding locations in different areas on the cloud platform page according to the different distribution locations of LoRa collection nodes and LoRa routing nodes, so as to facilitate observation.

[0020] Preferably, the node transmission step can transmit the digital signal collected by the sensor in the form of streaming data by adopting the Modbus protocol. The Modbus protocol is used for transmission between the LoRa acquisition node and the LoRa routing node, which can ensure that the encoding method of the receiving end and the transmitting end is the same during the data transmission process, and ensure that the effective information will not change during the data transmission process. At the same time, the Modbus protocol has expanded transmission capabilities between multiple devices due to other traditional data transmission protocols on the market. Therefore, when the method is applied to a highway environment, since a number of monitoring sensors need to be evenly spaced on both sides of the highway, the number of transmitting end devices is large, and the use of the Modbus protocol for data transmission can cope with the above-mentioned multi-device usage environment.

[0021] By adopting the above technical solution, this solution can improve the stability of the multi-device streaming data process through the Modbus protocol and reduce the risk of errors in the data transmission process.

[0022] Preferably, the information uploading step edits and integrates the information sending destination generated by the monitoring sensor into a RREP message. After the node receives the monitoring sensor information, it broadcasts the RREP message around its own location, so that the adjacent nodes reply to the current broadcast RREP message. The reply content includes the local identification code, the identification code of the local adjacent device and whether the local adjacent device contains the destination device. When the broadcasting node receives the reply data from all the adjacent nodes around itself, the transmission direction of the sensor data can be judged based on the reply data.

[0023] By adopting the above technical solution, this solution can quickly perform positioning analysis between nodes by broadcasting RREP messages, thereby quickly determining the accuracy of information transmission.

[0024] Preferably, when the broadcast node receives reply data from all adjacent nodes around itself, if there is a destination node around the adjacent nodes in the received information, the sensor information is sent through the target identification code, thereby relaying the sensor data through the adjacent nodes and finally transmitting it to the target node location. When the broadcast reply information does not contain the destination node, the broadcast node broadcasts the information to the adjacent nodes again and requires the adjacent nodes to repeat the broadcast information to their adjacent nodes, thereby expanding the node search range and finally finding the transmission line between the broadcast node and the destination node.

[0025] By adopting the above technical solution, the present solution can expand the search range of the present device by broadcasting information, thereby being able to perform an adaptive pathfinding effect within the network.

[0026] Preferably, when broadcasting RREP messages, some nodes are offline or malfunction. When the offline node receives the RREP message, it will not respond to the RREP message. When the faulty node receives the RREP message, it will reply with an error message to the broadcast node. At this time, the broadcast node will analyze and process the reply information of the adjacent nodes. When the nearby adjacent devices reply that there is an offline device but the offline device itself does not reply to the broadcast information, the offline device is reported through the cloud platform. When the information replied by the faulty device conflicts with the information replied by other adjacent nodes, the broadcast node reports to the cloud platform that there is a faulty node in the area.

[0027] By adopting the above technical solution, this solution can effectively reduce the troubleshooting intensity of the staff by reporting faults or offline nodes.

[0028] In summary, the present invention includes at least one of the following beneficial effects:

[0029] The present invention proposes a data collection method for highway service performance monitoring sensors based on LoRa Mesh, which supports sensor data with small data volume and low collection frequency requirements such as temperature and humidity, wind speed and direction, and tilt angle, and uses a wireless transmission network to send the data to a cloud platform. By reasonably deploying LoRa routing nodes, the monitoring system can perform stable data transmission in an environment with many obstacles. At the same time, the system has an automatic switching function for data transmission links. When the original link fails, a new transmission channel can be quickly constructed to ensure normal data transmission. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings required for describing the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other accompanying drawings can be obtained based on these accompanying drawings without paying creative work.

[0031] Figure 1 A step diagram of an embodiment of a highway service performance monitoring data collection method and system based on LoRa Mesh of the present invention;

[0032] Figure 2 4 is a system architecture diagram in an embodiment of the present invention. DETAILED DESCRIPTION

[0033] The following is combined with Figure 1-2 The present invention is described in further detail.

[0034] Embodiment 1

[0035] like Figure 1-Figure 2As shown, in this embodiment, in order to solve the existing problems, the present invention discloses a highway service performance monitoring data collection method and system based on LoRa Mesh, a LoRa module configuration step, and configures the core parameters of the LoRa collection node, the LoRa routing node, and the LoRa concentrator node through the LoRa AT command, including wireless rate, transmission power, device address, serial port baud rate and other information;

[0036] Cloud platform configuration steps: configure the monitoring sensor Modbus device address, value type, polling cycle and other information in the cloud platform software;

[0037] Node transmission step: the monitoring sensor information is transmitted to the Lora collection node through the Modbus protocol. The Lora collection node repackages the Modbus protocol data and transmits the data to the nearest Lora routing node through the Lora protocol.

[0038] Information upload step: After receiving the information, the Lora routing node sends a RREQ message to initiate a routing request, and sets the destination address to the address of the Lora concentrator node. When the intermediate node receives the RREQ message, it determines whether the current node is the destination node. If it is the destination node, it replies with the RREP message and the process ends. If it is not the destination node, it determines whether there is a route to the destination node. If so, it sends a RREP message. If not, it caches the RREQ message and forwards it, and the process ends. When the intermediate node receives the RREP message, it first updates the route to the destination node, the destination node predecessor list and other information, and then determines whether the node is the source node. If so, it uses the newly created routing link to send the cached data, otherwise it sends a unicast RREP message to the next hop of the route, and the process ends. When the intermediate node receives the RERR message, it deletes the faulty link and updates the routing table, and the process ends.

[0039] In the information aggregation step, the final data is aggregated to the Lora concentrator node, which caches and compresses the data and sends it to the 4G cloud network through the serial port transparent transmission method, and further sends it to the cloud platform;

[0040] In the data analysis step, the cloud platform software parses the received monitoring sensor data and displays, stores and analyzes it in real time.

[0041] The Lora module configuration step, when the module is set in an actual road environment, turns on the Lora module, adjusts the spacing between the Lora modules by moving, and detects the strength of the signal transmitted between the current Lora module and the surrounding Lora modules in real time. When the adjacent Lora modules move to the critical value of the strong signal range, the spacing between the current Lora modules is recorded, and then the Lora modules are installed with equal spacing at the current spacing size.

[0042] The cloud platform configuration step is to mark and connect several LoRa collection nodes and LoRa routing nodes, so that different locations of the highway can be managed and controlled according to the marked LoRa collection nodes and LoRa routing nodes on the cloud platform page, and the LoRa collection nodes and LoRa routing nodes in different areas can be quickly located during the use of the cloud platform by using geographic tags instead of the model codes used by the LoRa collection nodes and LoRa routing nodes on the cloud platform.

[0043] The node transmission step can transmit the digital signal collected by the sensor in the form of streaming data by adopting the Modbus protocol. The Modbus protocol is used for transmission between the LoRa acquisition node and the LoRa routing node, which can ensure that the encoding method of the receiving end and the transmitting end is the same during the data transmission process, and ensure that the effective information will not change during the data transmission process. At the same time, the Modbus protocol has the expanded transmission capability between multiple devices due to other traditional data transmission protocols on the market. Therefore, when the method is applied in a highway environment, since a number of monitoring sensors need to be evenly spaced on both sides of the highway, the number of transmitting end devices is large, so the use of the Modbus protocol for data transmission can cope with the above-mentioned multi-device usage environment.

[0044] The information uploading step edits and integrates the information sending destination generated by the monitoring sensor into a RREP message. After the node receives the monitoring sensor information, it broadcasts the RREP message around its own location, so that the adjacent nodes reply to the current broadcast RREP message. The reply content includes the local identification code, the identification code of the local adjacent device and whether the local adjacent device contains the destination device. When the broadcasting node receives the reply data from all the adjacent nodes around itself, the transmission direction of the sensor data can be judged based on the reply data.

[0045] When the broadcast node receives reply data from all adjacent nodes around itself, if there is a destination node around the adjacent nodes in the received information, the sensor information will be sent through the target identification code, so that it can be relayed by the adjacent nodes and finally the sensor data will be transmitted to the target node location. When the broadcast reply information does not contain the destination node, the broadcast node will broadcast the information to the adjacent nodes again and ask the adjacent nodes to repeat the broadcast information to their adjacent nodes, thereby expanding the node search range and finally finding the transmission line between the broadcast node and the destination node.

[0046] When broadcasting RREP messages, some nodes are offline or fail. When the offline node receives the RREP message, it will not respond to the RREP message. When the failed node receives the RREP message, it will reply with an error message to the broadcast node. At this time, the broadcast node will analyze and process the reply information of the adjacent nodes. When the nearby adjacent devices reply that there is an offline device but the offline device itself does not reply to the broadcast information, the offline device is reported through the cloud platform. When the information replied by the failed device conflicts with the information replied by other adjacent nodes, the broadcast node reports to the cloud platform that there is a failed node in the area.

[0047] The specific working principle is: the hardware part of the Lora node mainly includes the main controller, Lora RF chip, power module and communication circuit. The main controller controls the Lora RF chip through AT instructions. The self-organizing network function is realized through the routing protocol, and the routing protocol is integrated in the main control chip.

[0048] When the Lora routing node receives data, it needs to judge the message type and parse the destination address in the data packet, and then search the routing table to find the most suitable path. The routing protocol used in the present invention is the AODV protocol.

[0049] After receiving the information, the Lora routing node sends a RREQ message to initiate a routing request and sets the destination address to the address of the Lora concentrator node. When the intermediate node receives the RREQ message, it determines whether the current node is the destination node. If it is the destination node, it replies with the RREP message and the process ends. If it is not the destination node, it determines whether there is a route to the destination node. If so, it sends a RREP message. If not, it caches the RREQ message and forwards it, and the process ends. When the intermediate node receives the RREP message, it first updates the route to the destination node, the destination node predecessor list and other information, and then determines whether the node is the source node. If so, it uses the newly created routing link to send the cached data, otherwise it sends a unicast RREP message to the next hop of the route, and the process ends. When the intermediate node receives the RERR message, it deletes the faulty link and updates the routing table, and the process ends.

[0050] Embodiment 2

[0051] like Figure 2 As shown, in order to solve the existing problems, based on the same concept as the above-mentioned embodiment 1, a highway service performance monitoring system based on LoRa Mesh technology is proposed in this embodiment: the system is mainly composed of monitoring sensors, LoRa collection nodes, LoRa routing nodes, LoRa concentrators, cloud gateways and integrated management cloud platforms. The system architecture is as follows Figure 2 shown.

[0052] The main functions of each module are:

[0053] Monitoring sensors, used for field data perception, may include temperature and humidity sensors, wind speed and direction sensors, and inclination sensors that support ModBus communication protocol;

[0054] LoRa acquisition node, used to connect monitoring sensors to complete sensor data collection;

[0055] LoRa routing nodes are used to build Mesh networks, realize multi-hop transmission of sensor data, and provide self-organizing network functions;

[0056] LoRa concentrator, used to monitor sensor data aggregation;

[0057] Cloud gateway and cloud platform are used to transmit monitoring sensor data to the cloud platform and store it in the cloud platform.

[0058] This system is used based on the method in Example 1. Through the combination of several detection sensors and LoRa collection nodes, the current real-time data of each detection position of the highway can be collected and transmitted. The use of the LoRa data transmission protocol can improve the transmission stability of wireless information. Due to the particularity of the highway use environment, in order to control the use cost, the collection nodes and the detection sensors are usually evenly distributed on both sides of the highway, and the amount of information data collected by the detection sensors has the same periodicity. Therefore, compared with traditional LTE and other data transmission methods, more attention is paid to the data transmission rate. The LoRa data transmission protocol can ensure the stability of the signal transmission strength between nodes under the premise that the data transmission rate is not high, thereby increasing the distance between the LoRa collection nodes and reducing the use cost. At the same time, since the amount of data generated by the detection sensor is small, the use of the LoRa data transmission protocol will not block the sensor data, and the unique anti-interference ability of the LoRa data transmission protocol can ensure the accuracy of the data transmitted by the sensor, ensuring the accuracy of data collection of this device.

[0059] The above are all preferred embodiments of the present invention, and are not intended to limit the protection scope of the present invention. Therefore, any equivalent changes made based on the structure, shape, and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A method and system for collecting highway service performance monitoring data based on LoRa Mesh, comprising the following steps: Lora module configuration steps, configure the core parameters of Lora acquisition node, Lora routing node, and Lora concentrator node through Lora AT commands, including wireless rate, transmission power, device address, serial port baud rate and other information; Cloud platform configuration steps: configure the monitoring sensor Modbus device address, value type, polling cycle and other information in the cloud platform software; Node transmission step: the monitoring sensor information is transmitted to the Lora collection node through the Modbus protocol. The Lora collection node repackages the Modbus protocol data and transmits the data to the nearest Lora routing node through the Lora protocol. Information upload step: After receiving the information, the Lora routing node sends a RREQ message to initiate a routing request, and sets the destination address to the address of the Lora concentrator node. When the intermediate node receives the RREQ message, it determines whether the current node is the destination node. If it is the destination node, it replies with the RREP message and the process ends. If it is not the destination node, it determines whether there is a route to the destination node. If so, it sends a RREP message. If not, it caches the RREQ message and forwards it, and the process ends. When the intermediate node receives the RREP message, it first updates the route to the destination node, the destination node predecessor list and other information, and then determines whether the node is the source node. If so, it uses the newly created routing link to send the cached data, otherwise it sends a unicast RREP message to the next hop of the route, and the process ends; when the intermediate node receives the RERR message, it deletes the faulty link and updates the routing table, and the process ends; In the information aggregation step, the final data is aggregated to the Lora concentrator node, which caches and compresses the data and sends it to the 4G cloud network through the serial port transparent transmission method, and further sends it to the cloud platform; In the data analysis step, the cloud platform software parses the received monitoring sensor data and displays, stores and analyzes it in real time.

2. According to a LoRa Mesh-based highway service performance monitoring data collection method and system according to claim 1, it is characterized in that: The Lora module configuration step, when the module is set in an actual road environment, turns on the Lora module, adjusts the spacing between the Lora modules by moving, and detects the strength of the signal transmitted between the current Lora module and the surrounding Lora modules in real time. When the adjacent Lora modules move to the critical value of the strong signal range, the spacing between the current Lora modules is recorded, and then the Lora modules are installed with equal spacing at the current spacing size.

3. According to a LoRa Mesh-based highway service performance monitoring data collection method and system according to claim 1, it is characterized in that: The cloud platform configuration step is to mark and connect several LoRa collection nodes and LoRa routing nodes, so that different locations of the highway can be managed and controlled according to the marked LoRa collection nodes and LoRa routing nodes on the cloud platform page, and the LoRa collection nodes and LoRa routing nodes in different areas can be quickly located during the use of the cloud platform by using geographic tags instead of the model codes used by the LoRa collection nodes and LoRa routing nodes on the cloud platform.

4. According to a LoRa Mesh-based highway service performance monitoring data collection method and system according to claim 1, it is characterized in that: The node transmission step can transmit the digital signal collected by the sensor in the form of streaming data by adopting the Modbus protocol. The Modbus protocol is used for transmission between the LoRa acquisition node and the LoRa routing node, which can ensure that the encoding method of the receiving end and the transmitting end is the same during the data transmission process, and ensure that the effective information will not change during the data transmission process. At the same time, the Modbus protocol has the expanded transmission capability between multiple devices due to other traditional data transmission protocols on the market. Therefore, when the method is applied in a highway environment, since a number of monitoring sensors need to be evenly spaced on both sides of the highway, the number of transmitting end devices is large, so the use of the Modbus protocol for data transmission can cope with the above-mentioned multi-device usage environment.

5. According to a LoRa Mesh-based highway service performance monitoring data collection method and system according to claim 1, it is characterized in that: The information uploading step edits and integrates the information sending destination generated by the monitoring sensor into a RREP message. After the node receives the monitoring sensor information, it broadcasts the RREP message around its own location, so that the adjacent nodes reply to the current broadcast RREP message. The reply content includes the local identification code, the identification code of the local adjacent device and whether the local adjacent device contains the destination device. When the broadcasting node receives the reply data from all the adjacent nodes around itself, the transmission direction of the sensor data can be judged based on the reply data.

6. A method and system for collecting highway service performance monitoring data based on LoRa Mesh according to claim 5, characterized in that: When the broadcast node receives reply data from all adjacent nodes around itself, if there is a destination node around the adjacent nodes in the received information, the sensor information will be sent through the target identification code, so that it can be relayed by the adjacent nodes and finally the sensor data will be transmitted to the target node location. When the broadcast reply information does not contain the destination node, the broadcast node will broadcast the information to the adjacent nodes again and ask the adjacent nodes to repeat the broadcast information to their adjacent nodes, thereby expanding the node search range and finally finding the transmission line between the broadcast node and the destination node.

7. A method and system for collecting highway service performance monitoring data based on LoRa Mesh according to claim 6, characterized in that: When broadcasting RREP messages, some nodes are offline or fail. When the offline node receives the RREP message, it will not respond to the RREP message. When the failed node receives the RREP message, it will reply with an error message to the broadcast node. At this time, the broadcast node will analyze and process the reply information of the adjacent nodes. When the nearby adjacent devices reply that there is an offline device but the offline device itself does not reply to the broadcast information, the offline device is reported through the cloud platform. When the information replied by the failed device conflicts with the information replied by other adjacent nodes, the broadcast node reports to the cloud platform that there is a failed node in the area.

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