A positioning system and method based on low-power LoRa wireless network

Abstract

The application belongs to the technical field of LoRa wireless network positioning, and provides a positioning method, system and method based on a low-power LoRa wireless network.The method comprises a plurality of nodes, a plurality of gateways and a cloud platform, the nodes are connected with the gateways, the gateways are connected with the cloud platform, the nodes are used for reporting data to the gateways, the data comprises a node ID and a time when the node reports, the gateways are used for recording a time when the data is received and a signal value, and according to the time when the data is received and the time when the node reports, a time difference is calculated, and the time difference and the signal value are reported to the cloud platform, and the cloud platform is used for calculating the position of the node according to the time difference and the signal value.The application adopts a combination mode of signal value+time difference to calculate a distance based on the transmission characteristics of low-power LoRa, realizes more accurate positioning, has a wide coverage area, and can be applied to indoor and outdoor positioning.

Description

Technical Field

[0001] This invention belongs to the field of LoRa wireless network positioning technology, specifically relating to a positioning method and system based on a low-power LoRa wireless network. Background Technology

[0002] The statements in this section are merely background information related to the present invention and do not necessarily constitute prior art.

[0003] Currently, major positioning technologies can be broadly categorized into two types: outdoor positioning and indoor positioning. Outdoor positioning technologies, such as GPS and BeiDou, have poor penetration and are unsuitable for indoor positioning. Indoor positioning technologies, such as UWB, Bluetooth, and WiFi, have short communication distances and high power consumption, making them unsuitable for outdoor positioning. Therefore, there are very few technologies that can simultaneously solve indoor and outdoor positioning problems, and even fewer that also offer low power consumption. LoRa, as an emerging wireless transmission technology, possesses strong anti-interference capabilities, high power, high receiver sensitivity, and low power consumption, enabling long-distance transmission and wider coverage. Using LoRa to simultaneously achieve indoor and outdoor data transmission is easy. However, due to the high receiver sensitivity of LoRa, traditional RSSI value positioning methods have significant inaccuracies. Therefore, the positioning technology of current low-power LoRa wireless networks is inaccurate. Summary of the Invention

[0004] To address the aforementioned problems, this invention proposes a positioning system and method based on a low-power LoRa wireless network. Leveraging the transmission characteristics of low-power LoRa, this invention employs a combination of signal value and time difference to calculate distance, achieving more accurate positioning with wide coverage, and enabling indoor and outdoor positioning applications.

[0005] According to some embodiments, the present invention adopts the following technical solution:

[0006] In one aspect, the present invention provides a positioning system based on a low-power LoRa wireless network.

[0007] A positioning system based on a low-power LoRa wireless network includes: several nodes, several gateways, and a cloud platform, wherein the nodes are connected to the gateways, and the gateways are connected to the cloud platform;

[0008] The node is used to report data to the gateway, and the data includes the node ID and the time when the node reported the data.

[0009] The gateway is used to record the time and signal value when receiving data; and to calculate the time difference based on the time when the data is received and the time when the node reports the data, and to report the time difference and signal value to the cloud platform.

[0010] The cloud platform is used to calculate the location of the node based on the time difference and signal value.

[0011] Furthermore, the node includes a node time management unit and a data reporting unit.

[0012] The node time management unit is used to cooperate with the cloud platform and gateway to perform time calibration and to obtain the time when reporting data;

[0013] The data reporting unit is used to report data according to the period specified by the cloud platform.

[0014] Furthermore, the gateway includes a gateway time management unit, a time difference calculation unit, and a node information statistics and reporting unit.

[0015] The gateway time management unit is used to cooperate with the cloud platform to perform time calibration and calculate the time allocated to the nodes;

[0016] The time difference calculation unit is used to record the time when the data is received, parse the time when the node reports, obtain the time difference based on the difference between the time when the data is received and the time when the node reports, and send the time difference to the node information statistics reporting unit.

[0017] The node information statistics and reporting unit is used to package and report the recorded node ID, signal value, time difference and gateway ID to the cloud platform.

[0018] Furthermore, the time allocated to the node is equal to the time allocated by the gateway plus the transmission time.

[0019] Furthermore, the transmission time is obtained based on the data length and the current rate.

[0020] Furthermore, the cloud platform includes a cloud platform time management unit, a node and gateway registration unit, a data statistics unit, a location calculation unit, and a map display unit.

[0021] The cloud platform time management unit is used to allocate and synchronize the time of the cloud platform, gateway and nodes, and calibrate it according to a specified period.

[0022] The node and gateway registration unit is used to input node information and gateway information, and send the node information and gateway information to the data statistics unit; wherein, the node information includes the node ID, and the gateway information includes the gateway ID and the location where the gateway is installed;

[0023] The data statistics unit is used to collect node information, gateway information, signal values ​​received by each gateway, and time differences calculated by each gateway, and then send the collected data to the positioning calculation unit.

[0024] The positioning calculation unit is used to obtain the installation locations of at least three gateways stored in the node and gateway registration unit, and predict the range of the node by combining the gateway ID and signal value of the three gateways; based on the range of the node, combined with the time difference and communication rate, the distance value is calculated to obtain the location of the node.

[0025] The map display unit is used to display the location of the nodes and the movement trajectory of the nodes.

[0026] Furthermore, the data statistics unit is also used to mask redundant data. The determination of redundant data is based on the timeout period, which is equal to the quotient of the specified distance divided by the communication rate minus the time difference reported by the first gateway.

[0027] Secondly, the present invention provides a positioning method based on a low-power LoRa wireless network.

[0028] A positioning method based on a low-power LoRa wireless network includes: several nodes, several gateways, and a cloud platform, wherein the nodes are connected to the gateways, and the gateways are connected to the cloud platform;

[0029] The node reports data to the gateway, and the data includes the node ID and the time when the node reported the data.

[0030] The gateway records the time and signal value when receiving data; and calculates the time difference between the time when the data is received and the time when the node reports the data, and reports the time difference and signal value to the cloud platform.

[0031] The cloud platform calculates the location of the node based on the time difference and signal value.

[0032] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0033] 1. This invention provides more accurate positioning compared to traditional signal value positioning methods.

[0034] 2. Compared with WIFI and base station positioning, the present invention has lower cost, lower power consumption, and is easier to deploy.

[0035] 3. Compared with positioning from public platforms such as GPS and Beidou, the data of this invention is more secure. Attached Figure Description

[0036] The accompanying drawings, which form part of this invention, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an improper limitation of the invention.

[0037] Figure 1 This is a structural diagram of a positioning system based on a low-power LoRa wireless network, as shown in Embodiment 1 of the present invention.

[0038] Figure 2 This is a schematic diagram of the node transmission method shown in Embodiment 1 of the present invention;

[0039] Figure 3 This is a flowchart of the positioning method based on the low-power LoRa wireless network of the present invention. Detailed Implementation

[0040] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0041] It should be noted that the following detailed description is illustrative and intended to provide further explanation of the invention. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains.

[0042] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the scope of exemplary embodiments according to the invention. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the term "comprising" is used in this specification, it indicates the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0043] In this invention, terms such as "connected" and "linked" should be interpreted broadly, indicating a fixed connection, an integral connection, or a detachable connection; a direct connection or an indirect connection through an intermediate medium. Those skilled in the art can determine the specific meaning of these terms in this invention based on the specific circumstances, and they should not be construed as limitations on the invention.

[0044] Example 1

[0045] This embodiment provides a positioning system based on a low-power LoRa wireless network.

[0046] like Figure 1 As shown, the system topology consists of three components: nodes, gateways, and a cloud platform. The entire transmission process requires synchronization of all three, at least the nodes and gateways. Time synchronization is uniformly managed by the cloud platform. The transmission process is roughly as follows: nodes actively report data according to the reporting cycle set by the cloud platform. The data is broadcast, and all surrounding gateway devices can receive it. The data includes the node ID and the time of reporting. After receiving the data, the surrounding gateway devices record the signal value, parse the time of node reporting, calculate the time difference (received time - node reported time), and report the signal value and time difference to the cloud platform. The cloud platform statistically analyzes the data from multiple gateways, calculates the node location, and displays it.

[0047] In summary, nodes need to have a node time management unit and a data reporting unit.

[0048] The node time management unit is used in conjunction with the cloud platform and gateway to perform time calibration and obtain time when reporting data.

[0049] The data reporting unit needs to report data according to the cycle specified by the cloud platform. The data includes the node ID and the time of reporting, such as... Figure 2 As shown, Figure 2 The transmission method includes nodes.

[0050] The gateway needs to have a gateway time management unit, a time difference calculation unit, and a node information statistics and reporting unit.

[0051] The gateway time management unit is used to work with the cloud platform to perform time calibration and node time allocation. The error in node time allocation is calculated by the gateway. The error is due to the low LoRa communication rate, so the real-time time allocated to the node is slightly smaller. Therefore, the gateway needs to calculate the transmission time t1=l / s based on the current rate s and data length l. The time allocated to the node needs to be added to this transmission time, which is the error correction time.

[0052] The time difference calculation unit is responsible for recording the time when the node data is received, parsing the time reported by the node, and calculating the time difference (time difference = time received - time reported by the node).

[0053] The node information statistics and reporting unit is responsible for packaging and reporting data such as node ID, signal value, time difference, and gateway ID to the cloud platform.

[0054] The cloud platform needs to have a time management unit, a node and gateway registration unit, a data statistics unit, a location calculation unit, and a map display unit.

[0055] The cloud platform time management unit is used to allocate and synchronize the time of the cloud platform, gateway, and nodes, and to calibrate it according to a specified period.

[0056] The node and gateway registration unit is responsible for entering node and gateway information. Only gateways and nodes with information entered on the cloud platform can perform data parsing. This private network, which does not use the public internet, combined with data encryption, achieves absolute data security. The entered information includes: node ID (unique identifier), gateway ID (unique identifier), and the precise location (latitude and longitude) of the gateway installation.

[0057] The data statistics unit is responsible for compiling and delivering node and gateway data to the positioning calculation unit. The main data includes the node ID, the IDs of each gateway that received the node's information, the signal values ​​of the node received by each gateway, and the time difference calculated by each gateway. Since LoRa has a long transmission distance, data from gateways at a great distance not only cannot be used for node positioning but may even cause calculation errors. Therefore, the data statistics unit needs to shield redundant data, which can be achieved through data timeout. Data of the node that exceeds the timeout period Tc will no longer be counted. The timeout period Tc is equal to the specified distance k divided by the communication rate s and then minus the time difference t1 reported by the first gateway, i.e., Tc = k / s - t1.

[0058] The positioning and computing unit is responsible for data analysis and calculation. It uses gateway ID information and node signal values ​​transmitted from three or more gateways to find the specific location of the gateway from the node and gateway registration unit. Combining the node signal values ​​obtained from the three gateways, it roughly calculates the approximate range. Then, it calculates the distance value by using the time difference of multiple gateways (the time when the gateway receives the node data minus the node reporting time carried in the node data) and the communication rate. With three or more distance values ​​(the distance between the node and the gateway), the accurate location of the node can be obtained, thus achieving accurate positioning. The signal values ​​play a role in verification and improving the speed of data processing.

[0059] The map display unit is responsible for presenting the final data, namely, displaying the node locations and movement trajectories.

[0060] Example 2

[0061] like Figure 3 As shown, this embodiment provides a positioning method based on a low-power LoRa wireless network, and the implementation steps are as follows:

[0062] STP1 gateway registration involves adding gateway information on the cloud platform, including the precise location (latitude and longitude) of the gateway installation and the gateway's ID (unique identifier).

[0063] STP2 node registration involves adding node information, including the node's ID (unique identifier), to the cloud platform.

[0064] STP3 node access: The node accesses the network according to the access parameters. The cloud platform allocates the channel and rate parameters of the node to complete the link connection between the node, gateway and cloud platform.

[0065] STP4 gateway time synchronization: After the gateway is connected to the cloud platform, the cloud platform will synchronize the real-time time to the gateway. All gateway times must be synchronized and calibrated by the cloud platform at a specified period.

[0066] For STP5 node time synchronization, after the node powers on, it first enters the network through the gateway. During network entry, the cloud platform sends the node's reporting cycle and real-time time to the gateway. The gateway calculates the error value based on the current communication rate and adds the error value to the real-time time before sending the information to the node. At this time, the cloud platform, gateway, and node time are all synchronized. Subsequent calibration is performed periodically by the cloud platform.

[0067] STP6 nodes report heartbeats. Nodes report heartbeats periodically according to the reporting cycle and broadcast them to nearby gateway devices. When reporting, the node ID and the node's current time are reported at the same time.

[0068] STP7 gateway data reporting: After receiving node information, the gateway near the node records the current time, parses the signal strength of the node, and then calculates the time when the gateway received the data and the time when the node reported the data. The time difference between the two is then reported to the cloud platform along with the time difference, node ID, gateway ID, and node signal value.

[0069] STP8 cloud platform data statistics: The cloud platform receives data from multiple gateways near the node, stores them in columns, and after the maximum transmission time has passed, blocks the data from subsequent nodes.

[0070] The STP9 cloud platform performs positioning calculations. The cloud platform roughly calculates the approximate range by using ID information and node signal values ​​transmitted from multiple gateways. Then, it calculates the distance value by using the time difference and communication rate of multiple gateways. With distance values ​​from three or more points, the node location can be determined, thereby achieving accurate positioning.

[0071] The STP10 cloud platform map displays location data on the map, and the movement trajectory of nodes can be obtained by reporting data from multiple locations.

[0072] Furthermore, the transmission methods described in this invention include, but are not limited to, LoRa communication, as well as other wireless communications such as Bluetooth.

[0073] The above description is merely a preferred embodiment of the present invention and is not intended to limit the 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 positioning system based on a low-power LoRa wireless network, characterized in that, include: A number of nodes, a number of gateways, and a cloud platform, wherein the nodes are connected to the gateways, and the gateways are connected to the cloud platform; The node is used to report data to the gateway, and the data includes the node ID and the time when the node reported the data. The gateway is used to record the time and signal value when receiving data; The system calculates the time difference between the time the data is received and the time the node reports it, and then reports the time difference and signal value to the cloud platform. The cloud platform is used to calculate the location of the node based on the time difference and signal value; The gateway includes a gateway time management unit, a time difference calculation unit, and a node information statistics and reporting unit. The gateway time management unit is used to cooperate with the cloud platform to perform time calibration and calculate the time allocated to the nodes; The time allocated to the node is equal to the time allocated by the gateway plus the transmission time; The transmission time is obtained based on the data length and the current rate; The cloud platform includes a cloud platform time management unit, a node and gateway registration unit, a data statistics unit, and a location calculation unit. The cloud platform time management unit is used to allocate and synchronize the time of the cloud platform, gateway and nodes, and calibrate it according to a specified period. The node and gateway registration unit is used to input node information and gateway information, and send the node information and gateway information to the data statistics unit; wherein, the node information includes the node ID, and the gateway information includes the gateway ID and the location where the gateway is installed; The data statistics unit is used to collect node information, gateway information, signal values ​​received by each gateway, and time differences calculated by each gateway, and then send the collected data to the positioning calculation unit. The positioning calculation unit is used to obtain the installation locations of at least three gateways stored in the node and gateway registration unit, and predict the range of the node by combining the gateway ID and signal value of the three gateways; based on the range of the node, combined with the time difference and communication rate, the distance value is calculated to obtain the location of the node. The data statistics unit is also used to shield redundant data; The determination of redundant data is based on the timeout period; The timeout period Tc is calculated using the formula: Tc = k / s - t1, where k represents the specified distance, s represents the communication rate, and t1 represents the time difference reported by the first gateway.

2. The positioning system based on a low-power LoRa wireless network according to claim 1, characterized in that, The node includes a node time management unit and a data reporting unit. The node time management unit is used to cooperate with the cloud platform and gateway to perform time calibration and to obtain the time when reporting data; The data reporting unit is used to report data according to the period specified by the cloud platform.

3. The positioning system based on a low-power LoRa wireless network according to claim 1, characterized in that, The time difference calculation unit is used to record the time when the data is received, parse the time when the node reports, obtain the time difference based on the difference between the time when the data is received and the time when the node reports, and send the time difference to the node information statistics reporting unit. The node information statistics and reporting unit is used to package and report the recorded node ID, signal value, time difference and gateway ID to the cloud platform.

4. The positioning system based on a low-power LoRa wireless network according to claim 1, characterized in that, The cloud platform also includes a map display unit, which is used to display the location of the nodes and the movement trajectory of the nodes.

5. A positioning method based on a low-power LoRa wireless network, using the system described in claim 1, characterized in that, The node reports data to the gateway, and the data includes the node ID and the time when the node reported the data. The gateway records the time and signal value when receiving data; and calculates the time difference between the time when the data is received and the time when the node reports the data, and reports the time difference and signal value to the cloud platform. The cloud platform calculates the location of the node based on the time difference and signal value.

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