An underground fusion positioning system and method based on ad hoc radio

Abstract

The application is suitable for the technical field of mine positioning, and provides an underground fusion positioning system and method based on self-organizing network radio stations. The system comprises: a plurality of self-organizing network radio station nodes mounted in underground tunnels, and a dynamic Mesh network formed among the self-organizing network radio station nodes through a self-organizing network protocol; a multi-source signal access module integrated in each self-organizing network radio station node; a fusion positioning calculation unit arranged in each self-organizing network radio station node or an underground equipment terminal; and an underground equipment terminal loaded with a terminal communication module, which communicates with adjacent self-organizing network radio station nodes and reports position information. The application utilizes the self-organizing network characteristics of the self-organizing network radio stations, combines the underground 5G and WiFi signal propagation, and mutually fuses and supplements the calculation. On the premise of not significantly increasing the cost, the underground equipment positioning accuracy is greatly improved, the high-precision positioning can be continuously performed for 50 kilometers, and the positioning error is 30 cm.

Description

Technical Field

[0001] This invention relates to the field of mine positioning technology, specifically to an underground fusion positioning system and method based on self-organizing network radios. Background Technology

[0002] The enclosed space and complex electromagnetic environment of underground mines prevent satellite signals (GPS, BeiDou) from penetrating the strata, rendering mature surface-based satellite positioning technologies completely ineffective underground. Furthermore, the narrow, winding tunnels, dense metal supports, and severe dust and water mist create significant multipath effects and non-line-of-sight (NLOS) errors in the signal propagation of ranging / positioning technologies such as UWB, WiFi, and Bluetooth, severely degrading positioning accuracy.

[0003] In existing technologies, the following methods are mainly used for downhole positioning:

[0004] 1. UWB (Ultra-Wideband) Positioning: By deploying a large number of UWB anchor base stations, centimeter-level positioning can be achieved using Time Difference of Arrival (TDOA) or Angle of Arrival (AOA) algorithms; however, UWB base stations need to be densely deployed (one every 50-100 meters), resulting in high equipment costs, difficult installation and maintenance, and multipath effects in metallic environments can still lead to a decrease in accuracy;

[0005] 2.5G positioning: Utilizing the large bandwidth and multi-beam characteristics of 5G networks, meter-level positioning can be achieved through technologies such as DL-TDOA and UL-TDOA. However, the coverage of 5G base stations is limited, the construction cost of underground 5G networks is high, and the positioning accuracy of 5G alone is difficult to meet the needs of precise equipment scheduling.

[0006] 3. WiFi fingerprint positioning: A fingerprint database is established by pre-collecting WiFi signal strength at various locations in the tunnel. The terminal matches the fingerprint to achieve positioning. However, WiFi signals fluctuate greatly underground, the fingerprint database is difficult to maintain, and the positioning accuracy is only 3-10 meters, which cannot meet the positioning requirements of equipment.

[0007] 4. Self-organizing network base station positioning: For example, the underground personnel positioning system based on self-organizing network base stations disclosed in Chinese invention patent CN208509278U deploys wireless master and slave base stations along the tunnel. The locator communicates with the adjacent base stations in front and behind to achieve positioning. However, this solution only relies on a single radio frequency ranging and does not integrate the existing multi-source signals such as 5G and WiFi in the mine. The positioning robustness is insufficient in complex electromagnetic environments.

[0008] Existing downhole positioning technologies generally suffer from high costs, difficult deployment, and poor robustness of single signal sources. Therefore, there is an urgent need to provide a downhole fusion positioning system and method based on ad hoc network radios to overcome the shortcomings in current practical applications. Summary of the Invention

[0009] The purpose of this invention is to provide an underground fusion positioning system and method based on self-organizing network radios, aiming to solve the problems in the background art mentioned above.

[0010] This invention is implemented as follows: a fusion positioning system for underground wells based on self-organizing network radios, comprising:

[0011] Multiple self-organizing radio nodes are fixedly mounted in the underground roadway according to the communication distance, and the self-organizing radio nodes form a dynamic Mesh network through the self-organizing network protocol.

[0012] A multi-source signal access module is integrated into each of the aforementioned self-organizing network radio nodes and is used to access underground signals;

[0013] The fusion positioning calculation unit is set in each of the self-organizing network radio nodes or the underground equipment terminal, and is used to receive the signal propagation parameters obtained by the multi-source signal access module and calculate the current position of the underground equipment through the fusion algorithm.

[0014] And the downhole equipment terminal, equipped with a terminal communication module, communicates with the nearby self-organizing network radio node and reports its location information.

[0015] As a further aspect of the present invention: the self-organizing network radio node includes:

[0016] The radio body has an explosion-proof housing;

[0017] An omnidirectional antenna is mounted on the radio body to enable radio frequency communication between the self-organizing network radio nodes;

[0018] And a self-organizing network protocol stack, set within the radio itself, is used to automatically discover neighboring nodes, establish routes, and maintain a dynamic Mesh network topology.

[0019] As a further aspect of the present invention: the downhole signal includes 5G base station signal, WiFi access point signal, and radio frequency ranging signal between self-organizing network radio nodes;

[0020] The multi-source signal access module includes:

[0021] The 5G signal receiving unit is used to receive reference signals transmitted by the 5G base station in the mine and obtain signal strength, delay or angle of arrival parameters;

[0022] The WiFi signal receiving unit is used to scan and receive beacon signals transmitted by the underground WiFi access point and obtain received signal strength indication parameters.

[0023] And a radio frequency ranging unit, used to measure the radio frequency signal propagation time or signal strength between the self-organizing network radio station node and the downhole equipment terminal, and to obtain the distance parameters between the nodes.

[0024] As a further aspect of the present invention: the fusion positioning calculation unit includes:

[0025] The multi-source data fusion module is used to perform weighted fusion of the propagation parameters of the 5G signal, WiFi signal and radio frequency ranging signal, and dynamically adjust the weights according to the real-time quality of each signal source to suppress the error of a single signal source in a non-line-of-sight environment.

[0026] The location calculation module is used to calculate the real-time coordinates of the downhole equipment terminal based on the fused signal parameters, using a triangulation algorithm, a fingerprint matching algorithm, or an inertial navigation-assisted algorithm.

[0027] And an error correction module, used to dynamically correct the calculation results by utilizing the known relative positional relationships between the self-organizing network radio nodes.

[0028] As a further aspect of the present invention: the downhole equipment terminal further includes:

[0029] An inertial measurement unit is used to provide dead reckoning-assisted positioning in areas with signal obstruction.

[0030] It also includes a position output interface for outputting the calculated current position to the control system of the downhole equipment or the ground monitoring center.

[0031] As a further aspect of the present invention: the self-organizing network radio nodes are fixedly mounted on the roof or sidewall of the underground roadway at communication distance intervals of 200 meters to 500 meters.

[0032] As a further aspect of the present invention: the system supports high-precision positioning within a continuous 50-kilometer tunnel range, with a positioning error not exceeding 30cm.

[0033] As a further aspect of the present invention, the self-organizing network radio node also integrates a data relay function, used to transmit the positioning data and business data of the downhole equipment terminal back to the ground monitoring center through the dynamic Mesh network.

[0034] As a further aspect of the present invention: the self-organizing network radio node further includes a UWB signal receiving unit for receiving downhole UWB anchor point signals, and the fusion positioning calculation unit incorporates the ranging data of the UWB anchor point signals into the fusion calculation.

[0035] This invention also provides a method for underground fusion positioning based on self-organizing network radios, employing the system described above, and including the following steps:

[0036] S1. Multiple self-organizing radio nodes are fixedly mounted in the underground roadway at a preset interval, and the self-organizing radio nodes form a dynamic Mesh network through the self-organizing network protocol.

[0037] S2. By using the multi-source signal access module integrated in each of the self-organizing network radio nodes, obtain signal propagation parameters of at least two different types of signal sources, including underground 5G base station signals, WiFi access point signals and radio frequency ranging signals between the self-organizing network radio nodes.

[0038] S3. By using the fusion positioning calculation unit set in each of the self-organizing network radio nodes or downhole equipment terminals, the signal propagation parameters are fused and calculated to estimate the current position of the downhole equipment.

[0039] S4. The downhole equipment terminal communicates with the nearby self-organizing network radio node through its onboard terminal communication module and reports its location information.

[0040] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0041] This invention uses a self-organizing network radio as its core, actively integrating existing multi-source signals such as 5G and WiFi underground. When a signal source fails due to obstruction or multipath propagation, other signal sources can automatically supplement it, significantly improving positioning robustness. The self-organizing network radio nodes utilize existing underground 5G and WiFi infrastructure, eliminating the need for additional dedicated positioning equipment such as UWB anchors. Node spacing can reach 200-500 meters, significantly reducing deployment costs. The radio nodes automatically form a mesh network through a self-organizing network protocol. When a node fails or the tunnel topology changes, the network can automatically reconstruct, adapting to the dynamically changing underground working environment. Through multi-source signal fusion calculation and dynamic error correction, the system can support high-precision positioning in continuous 50-kilometer tunnels, with a positioning error not exceeding 30cm. Simultaneously, the self-organizing network radio nodes act as data relays, with positioning data and service data sharing the same network for backhaul, avoiding redundant construction. Attached Figure Description

[0042] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0043] Figure 1 This is a schematic diagram of the overall system architecture of the present invention.

[0044] Figure 2 This is a schematic diagram of the structure of the self-organizing network radio node in this invention.

[0045] Figure 3 This is a flowchart of the method of the present invention.

[0046] In the attached diagram: 100 - self-organizing network radio node, 110 - radio body, 120 - omnidirectional antenna, 130 - self-organizing network protocol stack, 200 - multi-source signal access module, 210 - 5G signal receiving unit, 220 - WiFi signal receiving unit, 230 - radio frequency ranging unit, 300 - fusion positioning calculation unit, 310 - multi-source data fusion module, 320 - position calculation module, 330 - error correction module, 400 - downhole equipment terminal. Detailed Implementation

[0047] The technical solution of the present invention will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0048] The present invention will be further explained below with reference to specific embodiments.

[0049] Example 1:

[0050] like Figure 1 As shown in the figure, the underground fusion positioning system based on self-organizing network radio provided in this embodiment mainly includes multiple self-organizing network radio nodes 100, multi-source signal access module 200, fusion positioning calculation unit 300 and underground equipment terminal 400.

[0051] The self-organizing network radio nodes 100 are fixedly mounted on the roof or sidewall of the underground roadway at communication distance intervals of 200-500 meters. For example... Figure 2 As shown, each ad hoc network radio node 100 includes a radio body 110, an omnidirectional antenna 120, and an ad hoc network protocol stack 130. The radio body 110 has an explosion-proof housing and complies with underground coal mine safety standards (MA mark); the omnidirectional antenna 120 is used to realize radio frequency communication between nodes; the ad hoc network protocol stack 130 is used to automatically discover neighboring nodes, establish routes, and maintain a dynamic mesh network topology. When a node fails or the tunnel topology changes, the network can be automatically reconstructed in milliseconds to ensure uninterrupted location services.

[0052] The multi-source signal access module 200 is integrated within each of the self-organizing network radio nodes 100, and includes a 5G signal receiving unit 210, a WiFi signal receiving unit 220, and a radio frequency ranging unit 230. The 5G signal receiving unit 210 receives the reference signal transmitted by the underground 5G base station and obtains the signal strength (RSRP), time delay (TA), or angle of arrival (AoA) parameters; the WiFi signal receiving unit 220 scans and receives the beacon signal transmitted by the underground WiFi access point and obtains the received signal strength indication (RSSI) parameter; the radio frequency ranging unit 230 measures the radio frequency signal propagation time (TOF) or signal strength between the self-organizing network radio node 100 and the underground equipment terminal 400 to obtain the distance parameters between the nodes.

[0053] The fusion positioning calculation unit 300 is located within each of the self-organizing network radio nodes 100 and includes a multi-source data fusion module 310, a position calculation module 320, and an error correction module 330. The multi-source data fusion module 310 performs weighted fusion of the propagation parameters of three types of signals: 5G, WiFi, and radio frequency ranging. It dynamically adjusts the weights based on the real-time quality of each signal source to suppress errors from a single signal source in non-line-of-sight environments. The position calculation module 320, based on the fused signal parameters, uses the Extended Kalman Filter (EKF) algorithm to fuse triangulation and inertial navigation assistance to calculate the real-time coordinates of the downhole equipment terminal 400. The error correction module 330 utilizes the known relative positional relationships between the self-organizing network radio nodes 100 (obtained through pre-calibration or self-organizing network ranging) to dynamically correct the calculation results and suppress accumulated errors.

[0054] The downhole equipment terminal 400 is equipped with a terminal communication module, an inertial measurement unit, and a position output interface. The terminal communication module communicates with the nearby self-organizing network radio node 100 to transmit and receive positioning data; the inertial measurement unit provides dead reckoning-assisted positioning in signal-blocked areas (such as curves and junctions); and the position output interface outputs the calculated current position to the downhole equipment's control system or the ground monitoring center.

[0055] Example 2:

[0056] In another implementation, the fusion positioning calculation unit 300 can be located within the underground equipment terminal 400, rather than within the self-organizing network radio nodes 100. In this case, each self-organizing network radio node 100 is only responsible for multi-source signal acquisition and raw data reporting, while the underground equipment terminal 400 receives the raw data from multiple nodes and performs local fusion calculation. This solution is suitable for scenarios where the equipment terminal has strong computing capabilities (such as unmanned mining trucks and intelligent mining equipment).

[0057] Example 3:

[0058] As another implementation method, the self-organizing network radio node 100 can also integrate a UWB signal receiving unit to receive existing UWB anchor point signals underground, further enriching the signal dimensions of multi-source fusion. When a UWB system has been deployed underground, this system can seamlessly connect to it, incorporating UWB ranging data into the fusion calculation, further improving positioning accuracy.

[0059] Example 4:

[0060] The self-organizing network radio node 100 also integrates data relay functionality. Business data from the downhole equipment terminal 400 (such as video surveillance and sensor data) can be transmitted back to the ground monitoring center through the Mesh network of the self-organizing network radio node 100, achieving integrated communication and positioning and avoiding redundant construction of communication networks.

[0061] Example 5:

[0062] This embodiment provides a method for underground fusion positioning based on self-organizing network radios, which can be implemented using the system described in any one of embodiments one to four above.

[0063] like Figure 3 As shown, the method includes the following steps:

[0064] S1. Multiple self-organizing radio nodes 100 are fixedly mounted at preset intervals in the underground roadway. The self-organizing radio nodes 100 form a dynamic mesh network through the self-organizing network protocol. Specifically, the self-organizing radio nodes 100 are fixedly mounted on the roof or sidewall of the underground roadway at communication distance intervals of 200-500 meters. Each node automatically discovers neighboring nodes, establishes routes, and maintains the dynamic mesh network topology through the self-organizing network protocol stack 130.

[0065] S2. Through the multi-source signal access module 200 integrated in each of the self-organizing network radio nodes 100, signal propagation parameters of at least two different types of signal sources are obtained. The signal sources include the underground 5G base station signal, the WiFi access point signal, and the radio frequency ranging signal between the self-organizing network radio nodes 100. Specifically, the 5G signal receiving unit 210 receives the reference signal transmitted by the underground 5G base station and obtains the signal strength, delay, or angle of arrival parameters; the WiFi signal receiving unit 220 scans and receives the beacon signal transmitted by the underground WiFi access point and obtains the received signal strength indication parameter; the radio frequency ranging unit 230 measures the radio frequency signal propagation time or signal strength between the self-organizing network radio node 100 and the underground equipment terminal 400 and obtains the distance parameters between the nodes.

[0066] S3. The signal propagation parameters are fused and calculated by the fusion positioning calculation unit 300 set in each of the self-organizing network radio nodes 100 or the downhole equipment terminal 400 to estimate the current position of the downhole equipment. Specifically, the multi-source data fusion module 310 performs weighted fusion of the propagation parameters of each signal source and dynamically adjusts the weights according to the real-time quality of each signal source to suppress the error of a single signal source in a non-line-of-sight environment; the position calculation module 320 calculates the real-time coordinates of the downhole equipment terminal 400 based on the fused signal parameters using a triangulation algorithm, fingerprint matching algorithm, or inertial navigation-assisted algorithm; the error correction module 330 dynamically corrects the calculation results using the known relative positional relationships between the self-organizing network radio nodes 100.

[0067] S4. The downhole equipment terminal 400 communicates with the nearby self-organizing network radio node 100 via its onboard terminal communication module to report its location information. The location output interface of the downhole equipment terminal 400 outputs the calculated current location to the control system of the downhole equipment or the surface monitoring center.

[0068] Through the above steps, this method achieves high-precision positioning of equipment terminals in complex downhole environments.

[0069] Positioning effectiveness verification:

[0070] A field test was conducted in an underground mine roadway: the roadway was 50 kilometers long, and 120 self-organizing network radio nodes were deployed with an average spacing of approximately 420 meters. The underground equipment terminal 400 was mounted on a mining unmanned vehicle traveling at 20 km / h. The test results showed that the system could achieve high-precision positioning continuously over 50 kilometers, with a positioning error of no more than 30 cm, meeting the requirements for precise scheduling and unmanned operation of underground equipment.

[0071] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A well-drilled fusion positioning system based on self-organizing network radios, characterized in that, include: Multiple self-organizing radio nodes (100) are fixedly mounted in the underground roadway according to the communication distance, and the self-organizing radio nodes (100) form a dynamic Mesh network through the self-organizing network protocol. A multi-source signal access module (200) is integrated into each of the self-organizing network radio nodes (100) and is used to access underground signals; The fusion positioning calculation unit (300) is set in each of the self-organizing network radio nodes (100) or the downhole equipment terminal (400) to receive the signal propagation parameters obtained by the multi-source signal access module (200) and calculate the current position of the downhole equipment through the fusion algorithm. And the downhole equipment terminal (400), equipped with a terminal communication module, communicates with the nearby self-organizing network radio node (100) and reports location information.

2. The system according to claim 1, characterized in that, The self-organizing network radio node (100) includes: The radio body (110) has an explosion-proof housing; An omnidirectional antenna (120) is disposed on the radio body (110) to realize radio frequency communication between the self-organizing network radio nodes (100); And a self-organizing network protocol stack (130), which is set in the radio body (110), is used to automatically discover neighboring nodes, establish routes and maintain dynamic Mesh network topology.

3. The system according to claim 1, characterized in that, The downhole signals include 5G base station signals, WiFi access point signals, and radio frequency ranging signals between self-organizing network radio nodes (100). The multi-source signal access module (200) includes: The 5G signal receiving unit (210) is used to receive the reference signal transmitted by the 5G base station in the well and obtain the signal strength, delay or angle of arrival parameters. WiFi signal receiving unit (220) is used to scan and receive beacon signals transmitted by the underground WiFi access point and obtain received signal strength indication parameters; And a radio frequency ranging unit (230) is used to measure the radio frequency signal propagation time or signal strength between the self-organizing network radio station node (100) and the downhole equipment terminal (400) to obtain the distance parameters between the nodes.

4. The system according to claim 3, characterized in that, The fusion positioning calculation unit (300) includes: The multi-source data fusion module (310) is used to perform weighted fusion of the propagation parameters of the 5G signal, WiFi signal and radio frequency ranging signal, and dynamically adjust the weights according to the real-time quality of each signal source in order to suppress the error of a single signal source in a non-line-of-sight environment. The position calculation module (320) is used to calculate the real-time coordinates of the downhole equipment terminal (400) based on the fused signal parameters, using a triangulation algorithm, a fingerprint matching algorithm, or an inertial navigation-assisted algorithm. And an error correction module (330) is used to dynamically correct the solution results by utilizing the known relative positional relationships between the self-organizing network radio nodes (100).

5. The system according to claim 1, characterized in that, The downhole equipment terminal (400) also includes: An inertial measurement unit is used to provide dead reckoning-assisted positioning in areas with signal obstruction. It also includes a position output interface for outputting the calculated current position to the control system of the downhole equipment or the ground monitoring center.

6. The system according to claim 1, characterized in that, The self-organizing network radio nodes (100) are fixedly mounted on the roof or sidewall of the underground roadway at communication distance intervals of 200 meters to 500 meters.

7. The system according to claim 1, characterized in that, The system supports high-precision positioning within a continuous 50-kilometer tunnel range, with a positioning error of no more than 30 cm.

8. The system according to claim 1, characterized in that, The self-organizing network radio node (100) also integrates a data relay function, which is used to transmit the positioning data and business data of the downhole equipment terminal (400) back to the ground monitoring center through the dynamic Mesh network.

9. The system according to claim 1, characterized in that, The self-organizing network radio node (100) also includes a UWB signal receiving unit for receiving downhole UWB anchor point signals, and the fusion positioning calculation unit (300) incorporates the ranging data of the UWB anchor point signals into the fusion calculation.

10. A method for underground fusion positioning based on self-organizing network radios, employing the system described in claims 1 to 9, characterized in that, Includes the following steps: S1. Multiple self-organizing radio nodes (100) are fixedly mounted in the underground roadway at a preset interval, and the self-organizing radio nodes (100) form a dynamic Mesh network through the self-organizing network protocol. S2. By using the multi-source signal access module (200) integrated in each of the self-organizing network radio nodes (100), obtain signal propagation parameters of at least two different types of signal sources, including underground 5G base station signals, WiFi access point signals and radio frequency ranging signals between the self-organizing network radio nodes (100). S3. By using the fusion positioning calculation unit (300) set in each of the self-organizing network radio nodes (100) or the downhole equipment terminal (400), the signal propagation parameters are fused and calculated to estimate the current position of the downhole equipment. S4. The downhole equipment terminal (400) communicates with the nearby self-organizing network radio node (100) through its onboard terminal communication module and reports its location information.

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