An event robust generation system for wireless microseismic events and method of use

Abstract

This invention discloses a robust event generation system and method for wireless microseismic events, relating to the field of microseismic monitoring technology in tunnel construction. It includes a wireless microseismic acquisition instrument, an acquisition server, microseismic sensors, and a communication server. The communication server is equipped with a dual-mode communication unit for both WiFi and LoRa. The wireless microseismic acquisition instrument and the acquisition server are connected via a multi-mode communication network of the communication server, supporting multiple waveform transmission modes. Robust waveform transmission is achieved through local storage-upload-verification-acknowledgment-retransmission. Dynamic generation of microseismic events is completed collaboratively using three data tables: Unwave, Wave, and Event. Delayed waveforms with trigger times within the Δt time window are added to the generated events, and the data tables are updated synchronously. This invention effectively solves the problems of wireless communication interference, incomplete waveform transmission, incomplete event generation, and inability to complete delayed waveforms, and is suitable for full-area rockburst monitoring and early warning in tunnels.

Description

Technical Field

[0001] This invention relates to the field of microseismic monitoring technology in tunnel construction, and more specifically to an event robust generation system and method for wireless microseismic events. Background Technology

[0002] In the construction of deeply buried tunnels under high ground stress, geological disasters such as rock bursts and surrounding rock collapses occur frequently, seriously threatening construction safety and project progress. Microseismic monitoring is a core technical means to prevent such disasters. The microseismic waveforms generated by rock mass fracturing and displacement contain key information such as the stress state and degree of fracturing of the surrounding rock. By acquiring, transmitting, and analyzing signals to generate complete microseismic events, the stability of the surrounding rock can be monitored in real time, disaster risks can be identified in advance, and construction optimization can be guided. The completeness and accuracy of microseismic events directly determine the reliability of monitoring and early warning, and are the core link of microseismic monitoring technology.

[0003] Traditional microseismic monitoring uses wired transmission, which is costly and labor-intensive to lay cables, is easily damaged by construction machinery, and is difficult to maintain. Furthermore, it is limited by space constraints, making it difficult to flexibly adjust monitoring points and has poor scalability, making it unsuitable for the narrow, dispersed, and dynamically advancing construction environment of tunnels. Wireless microseismic monitoring, on the other hand, eliminates the need for extensive cabling, offering advantages such as flexible deployment, convenient installation, low maintenance costs, and strong scalability. It allows for point adjustments as construction progresses, achieving comprehensive monitoring of the entire tunnel area without blind spots, reducing the risk of system damage, and ensuring monitoring continuity. This has made it the mainstream development direction for microseismic monitoring in tunnel construction.

[0004] In practical applications of wireless microseismic monitoring in tunnels, the complex construction environment and unstable wireless communication links caused by construction activities and cable layouts lead to data packet loss, delays, and interruptions. Waveform loss directly results in missed events and misjudgments. Using only WiFi or LoRa cannot meet all requirements; WiFi offers high speed but short range, while LoRa offers long range but low speed, failing to adapt to the differentiated needs of high-speed acquisition at the tunnel face and stable long-distance transmission. Using fixed threshold triggers without considering waveform upload delays and lacking effective filtering and verification mechanisms makes the system susceptible to interference signals, leading to incomplete or incorrect event generation. Waveform transmission and event generation are independent and lack a coordination mechanism; when transmission is abnormal, the event generation stage cannot respond, resulting in event loss. Events are generated only once, and delayed waveform uploads cannot be added to already generated events, resulting in incomplete event waveforms. This severely reduces the accuracy of seismic source location and the reliability of rockburst early warning, representing the core pain point of existing technologies.

[0005] Therefore, ensuring the integrity and stability of event generation in wireless microseismic monitoring is a problem that urgently needs to be solved by those skilled in the art. Summary of the Invention

[0006] In view of this, the present invention provides an event robust generation system and method for wireless microseismic events, which solves the technical problem of incomplete and unstable event generation in wireless microseismic monitoring, and provides reliable monitoring support for tunnel construction safety.

[0007] To achieve the above objectives, the present invention adopts the following technical solution: A robust event generation system for wireless microseismic events includes: a wireless microseismic acquisition device, an acquisition server, several microseismic sensors, and a communication server. The wireless microseismic acquisition device is connected to the microseismic sensors, and the wireless microseismic acquisition device and the acquisition server are connected via a multi-mode communication network of the communication server. The wireless microseismic acquisition device has a built-in communication module that switches communication modes according to preset conditions. The acquisition server includes a waveform robust transmission module, a microseismic event dynamic generation module, and several communication modules. The waveform robust transmission module includes a received data verification and response unit to realize waveform data verification, response, and retransmission. The microseismic event dynamic generation module has built-in Unwave table, Wave table, and Event table, which work together to dynamically generate microseismic events. The LoRa module of the acquisition server communicates with the wireless microseismic acquisition device.

[0008] Preferably, the wireless microseismic acquisition device includes a WiFi communication module and several LoRa communication modules to realize parallel transmission of waveform data through multiple wireless channels. The acquisition server integrates the waveform data into a complete waveform according to the packet transmission mark. The communication mode switching of the wireless microseismic acquisition device is based on the signal strength and data transmission quality. If the WiFi signal strength is lower than a preset threshold (typical value -80dB), an AP relay module can be added to enhance the communication quality.

[0009] Preferably, the micro-vibration event dynamic generation module further includes a waveform recovery unit. The waveform recovery unit is used to query the Event table and the Unwave table. When there is already a micro-vibration event within a time interval Δt near the trigger time of the newly received waveform, the waveform is recovered and added to the generated event, and the Event table and the Wave table are rewritten.

[0010] Preferably, the dynamic generation of the microseismic events adopts... The dynamic value acquisition method determines the time range for event generation based on the sensor's installation location, avoiding repeated searches and improving event generation efficiency while ensuring event integrity.

[0011] A method for using a robust event generation system for wireless microseismic events includes: deploying a microseismic sensor, a wireless microseismic data acquisition device, a communication server, and a data acquisition server; adding an AP repeater module to enhance the WiFi signal strength and extend the communication distance based on the WiFi signal strength detected by the data acquisition server; selecting a corresponding waveform transmission mode and a corresponding wireless microseismic data acquisition device communication mode based on signal strength and data transmission speed requirements; after the microseismic sensor triggers the wireless microseismic data acquisition device to acquire waveform data, the wireless microseismic data acquisition device first completes local storage of the waveform data, and then uploads the waveform data to the data acquisition server according to the selected transmission mode and communication method; the data acquisition server checks the integrity and anomaly of the received waveform data; if the check is complete and there are no anomalies, it sends a response signal to the data acquisition device, which deletes the corresponding local waveform file and continues to upload the next data; if the check finds data anomalies, or if the data acquisition device does not receive a response signal within 5 seconds, the data acquisition device retransmits the waveform data until the transmission is successful.

[0012] The local storage includes a power-off lossless storage unit and a slow storage unit that does not lose data when power is off.

[0013] Preferably, the Unwave table records and saves waveforms that did not participate in the generation of microseismic events, the Wave table records and saves waveforms that participated in the generation of microseismic events, and the Event table records and saves the generated microseismic event information. After receiving the waveform file, the acquisition server stores the waveform and extracts the acquisition trigger time; it queries the Event table and Unwave table to determine the triggering situation within a time interval Δt near the trigger time, and performs corresponding operations in coordination with the waveform robust transmission module, specifically as follows: if a microseismic event has already been triggered within a time interval Δt near the trigger time, a waveform remediation operation is performed to remediate the waveform into the generated microseismic event, rewrite the Event table and Wave table, update the waveform information contained in the event, and ensure the integrity of the generated event; if the triggering event is not triggered, the acquisition server performs a waveform remediation operation to remediate the waveform into the generated microseismic event, rewrites the Event table and Wave table, and updates the waveform information contained in the event to ... Wave table and Wave table, and updates the waveform information contained in the event to ensure the integrity of the generated event; if the triggering event is not triggered, the acquisition server performs a waveform remediation operation to remediate the waveform into the generated microseismic event, and performs a waveform remediation operation to remediate the waveform into the generated microseismic event, and performs a waveform remediation operation to remediate the waveform into the generated microseismic event, and performs a waveform remediation operation to remediate the waveform into the generated microseismic event, and performs a waveform remediation operation to remediate the waveform into the generated microseismic If no microseismic event occurs within a time interval Δt near the trigger time and no other waveforms are triggered, the waveform information is written to the Unwave table for further evaluation. If other waveforms are triggered within a time interval Δt near the trigger time but no microseismic event is generated, the Unwave table is queried to determine whether the number of waveforms triggered within Δt reaches n or more. Here, n is the sensor trigger number threshold (typical value n≥4). If the number of waveforms reaches n or more, a new microseismic event is generated, and the relevant waveform is deleted from the Unwave table and written to the Wave table and Event table. If the threshold is not reached, the waveform is written to the Unwave table. Waveform information stored in the Unwave table that has exceeded the preset duration and has not participated in event generation is cleaned up every 1 to 2 hours.

[0014] Preferably, the The method of determining the coordinates is based on the dynamic value acquisition of the sensor coordinates. Calculate using the following formula: ; in, , Number the different sensors; The coordinates of the sensor numbered i; The P-wave velocity of the microseismic event at a certain engineering site; To account for path correction parameters based on spatial diffraction and geological structure, automatic execution is performed when the sensor position moves and the coordinates are modified. Correct the calculation.

[0015] Preferably, the waveform transmission operating mode includes: Static optimal working mode 1: Before the data acquisition device is initialized, the signal strength of the current WiFi and LoRa communication methods is detected by the built-in communication module. The transmission rate of each method is estimated based on the signal strength, and the communication method with the best transmission rate is selected. After initialization, this method is used to transmit data. Dynamic Optimal Working Mode 2: Before each waveform data transmission, the data acquisition unit detects the signal strength of both WiFi and LoRa communication methods in real time, estimates the corresponding transmission rate, dynamically determines the optimal transmission method, and transmits the current waveform data according to this method, ensuring that each waveform transmission is in the optimal state. Fastest transmission mode: When the signal strength of each wireless transmission method allows, the waveform data is packetized according to preset rules and assigned a unique transmission marker. The idle wireless communication method is selected to send the waveform data. The acquisition server integrates the packetized waveform data into a complete waveform according to the transmission marker.

[0016] Preferably, when the wireless microseismic acquisition device uploads waveform data, it simultaneously sends a checksum of the data. After receiving the waveform data, the acquisition server calculates the checksum of the received data and compares it with the checksum sent by the wireless microseismic acquisition device. If the comparison matches, the waveform data is determined to be complete; if the comparison does not match, the data is determined to be abnormal, triggering the wireless microseismic acquisition device to re-upload.

[0017] As can be seen from the above technical solution, compared with the prior art, the present invention discloses an event robust generation system and usage method for wireless microseismic events. It adopts a WiFi and LoRa multi-mode collaborative communication scheme, and combined with a communication server, it can flexibly enhance the signal and communication distance according to the WiFi signal strength. It can flexibly switch the communication mode according to the needs of different monitoring areas in the tunnel, which solves the problems of insufficient coverage and poor adaptability of a single communication mode. It realizes stable transmission of microseismic data in the entire tunnel area, and at the same time adapts to the monitoring needs of instantaneous rockbursts near the tunnel face and time-delayed and chain rockbursts far away from the tunnel face.

[0018] The LoRa communication mode has been optimized. Through multiple designs, including one-to-one master-slave inversion communication, multiple LoRa module configuration on the acquisition server, and parallel transmission of multiple LoRa modules on the acquisition instrument, the data transmission rate in the LoRa communication mode has been effectively improved. This solves the rate bottleneck of traditional many-to-one LoRa communication and meets the transmission requirements of high-frequency micro-vibration waveform data.

[0019] Three waveform transmission modes were designed, which can be flexibly selected according to the tunnel construction environment and signal strength. This ensures the stability of transmission and maximizes transmission efficiency, adapting to the differentiated needs of different monitoring scenarios and further improving the flexibility and practicality of the system.

[0020] The robust waveform transmission mechanism has been strengthened. Through a closed-loop process of "local storage-upload-verification-response-retransmission" combined with the host computer's data reception verification and response mechanism, the problem of incomplete waveform transmission caused by wireless communication packet loss, data anomalies, and transmission interruptions has been effectively solved. This ensures the integrity and reliability of microseismic waveform data and provides high-quality data support for robust generation of microseismic events and waveform recovery.

[0021] A dynamic microseismic event generation mechanism was designed. By working together with the three information tables of Unwave, Wave, and Event, the problem of incomplete microseismic event generation caused by waveform upload delay was effectively solved. At the same time, by using an adjustable sensor trigger number threshold, the mechanism can adapt to the differences in sensor spacing in different tunnel projects, improve the accuracy of microseismic event classification and anti-interference ability, and avoid event omission and misjudgment.

[0022] This invention features a pioneering waveform recovery mechanism for microseismic events. This is the most crucial and innovative aspect of the invention. By querying the Event and Unwave tables, the temporal correlation between generated events and delayed uploaded waveforms is identified. The delayed uploaded waveforms are then added to the generated microseismic events, rewriting the Event and Wave tables. This completely solves the core problem of existing technologies where "delayed waveforms cannot be added after an event is generated," significantly improving the integrity of microseismic events and providing data support for high-precision seismic source location and reliable rockburst early warning. This is also one of the core differences between this invention and existing technologies.

[0023] It achieves coordinated synchronization of waveform transmission, waveform recovery, and event generation, with no interference between the three and real-time response, improving the real-time performance and stability of microseismic event generation. The entire system has a simple structure, is easy to operate, and has low maintenance costs. It can be widely used in various tunnel construction microseismic monitoring scenarios and has high practicality and promotion value. Attached Figure Description

[0024] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the provided drawings without creative effort.

[0025] Figure 1 This is a schematic diagram of the structure provided by the present invention; Figure 2 This is a schematic diagram of the dynamic generation and waveform recovery process for microseismic events provided by the present invention. Detailed Implementation

[0026] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. 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.

[0027] This invention discloses an event robust generation system for wireless microseismic events, such as... Figure 1 As shown, the system includes a wireless microseismic acquisition device, an acquisition server, several microseismic sensors, and a communication server. The wireless microseismic acquisition device is connected to the microseismic sensors, and the wireless microseismic acquisition device and the acquisition server are connected via a multi-mode communication network of the communication server. The wireless microseismic acquisition device has a built-in communication module that switches communication modes according to preset conditions. The acquisition server includes a waveform robust transmission module, a microseismic event dynamic generation module, and several communication modules. The waveform robust transmission module includes a received data verification and response unit to realize waveform data verification, response, and retransmission. The microseismic event dynamic generation module has built-in Unwave table, Wave table, and Event table, which work together to dynamically generate microseismic events. The LoRa module of the acquisition server communicates with the wireless microseismic acquisition device.

[0028] The wireless microseismic acquisition device has a built-in WiFi communication module and at least one LoRa communication module, supporting 2.4G and 5G frequency band WiFi 6 network and LoRa network communication. The communication mode can be switched according to the communication requirements and signal strength of the tunnel monitoring environment. Optionally, each wireless microseismic acquisition device can be equipped with multiple LoRa communication modules to realize parallel transmission through multiple wireless channels. The communication server includes a WiFi communication module and several LoRa communication modules, enabling parallel transmission of waveform data through multiple wireless channels. The acquisition server integrates the waveform data into a complete waveform according to the packet transmission markers. The communication mode switching of the wireless microseismic acquisition instrument is preset based on signal strength and data transmission quality. If the WiFi signal strength is lower than the preset threshold, the communication quality is enhanced by adding an AP relay module.

[0029] The acquisition server is equipped with a robust waveform transmission module, a dynamic microseismic event generation module, and multiple LoRa communication modules. The robust waveform transmission module is used to achieve complete transmission of microseismic waveforms. It includes a received data verification and response unit to detect the integrity and anomalies of the received data and to send response or anomaly signals back to the wireless microseismic acquisition instrument. The dynamic microseismic event generation module is used to dynamically generate complete microseismic events based on the received waveform data. The dynamic microseismic event generation module includes an Unwave table, a Wave table, and an Event table to store waveform information that did not participate in event generation, waveform information that participated in event generation, and microseismic event information, respectively. The dynamic microseismic event generation module also includes a waveform compensation unit. The waveform compensation unit queries the Event table and the Unwave table. When a microseismic event already exists within a time interval Δt around the trigger time of a newly received waveform, the waveform is compensated and added to the already generated event, and the Event table and the Wave table are rewritten. The multiple LoRa modules in the acquisition server all act as slaves, achieving one-to-one communication with the wireless microseismic acquisition instrument (master), solving the rate bottleneck of multi-acquisition instrument collaborative transmission. The system supports three waveform transmission modes, which can be switched according to actual monitoring needs: Static Optimal Mode 1, Static Optimal Mode 2, and Fastest Transmission Mode.

[0030] Microseismic events are dynamically generated using The dynamic value acquisition method determines the time range for event generation based on the sensor's installation location, avoiding repeated searches and improving event generation efficiency while ensuring event integrity.

[0031] A method for using an event robust generation system for wireless microseismic events, such as... Figure 2 As shown, the method applied to microseismic monitoring during tunnel construction includes the following steps: System initialization and communication mode adaptation: Deploy microseismic sensors, wireless microseismic acquisition devices, and acquisition servers. Based on the WiFi signal strength in the tunnel monitoring area, add AP repeater modules as needed to enhance WiFi signal strength and communication distance. Configure LoRa communication mode, adopting a one-to-one, master-slave inverted approach, i.e., the wireless microseismic acquisition device acts as the LoRa master, and multiple LoRa modules in the acquisition server act as slaves, achieving one-to-one communication with the corresponding acquisition server. If it is necessary to further improve the LoRa transmission rate, equip each wireless microseismic acquisition device with multiple LoRa communication modules to achieve parallel transmission through multiple wireless channels.

[0032] Select the waveform transmission mode: Based on the tunnel construction environment, signal strength, and monitoring requirements, select the appropriate waveform transmission mode. The three modes are as follows: Static optimal working mode 1: Before the data acquisition device is initialized, the transmission rate is estimated based on the signal strength of each communication method (WiFi, LoRa), the optimal transmission method is determined, and this method is used to transmit data continuously. Dynamic Optimal Working Mode 2: Before each transmission of waveform data, the data acquisition instrument estimates the transmission rate of each transmission method based on the real-time signal strength, determines the optimal transmission method, and transmits data according to this method. Fastest transmission mode: When the signal strength of each wireless transmission method allows (typically the judgment criterion is a signal strength greater than -80dB), the waveform data is divided into packets, and an idle wireless communication method is selected for transmission. The acquisition server (host computer) integrates the packet data into a complete waveform according to the transmission mark.

[0033] Robust transmission of microseismic waveforms: After the microseismic sensor triggers the wireless microseismic data acquisition instrument to collect waveform data, the acquisition instrument first completes the local storage of the waveform file, and then uploads the waveform file to the acquisition server according to the selected transmission mode and communication method. The acquisition server performs integrity and anomaly checks on the received waveform file through the data verification and response unit. If the check is complete and there are no anomalies, the server sends a response signal to the acquisition instrument, which deletes the corresponding local waveform file and continues to upload the next file. If the check finds data anomalies, or if the acquisition instrument does not receive a response signal within 5 seconds, the acquisition instrument resends the waveform file until the transmission is successful. Waveform transmission, acquisition, and storage are performed synchronously and do not interfere with each other.

[0034] Local storage includes high-speed, power-loss-free storage units (typically SDRAM, SRAM, etc.) and slow storage units (typically NAND FLASH, SD cards, etc.) that retain data even when power is off. The slow storage units can store a large number of waveforms locally, ensuring that waveforms are not lost even if wireless communication experiences a prolonged failure. Once wireless communication is restored, the locally stored waveforms will be uploaded to the acquisition server. Under the action of the robust event generation system, event recovery will be performed to ensure the integrity of event generation.

[0035] Dynamic generation and waveform recovery of microseismic events (core steps): After the acquisition server receives the waveform, it stores the waveform and extracts the acquisition trigger time; it queries the Event table and Unwave table to determine the triggering status within a time interval Δt near the trigger time and performs corresponding operations. The Unwave table records and saves waveforms that did not participate in the generation of microseismic events, the Wave table records and saves waveforms that participated in the generation of microseismic events, and the Event table records and saves the generated microseismic event information, as detailed below: If a micro-seismic event has already been triggered within a time interval Δt near the triggering time: perform waveform recovery operation to recover the waveform into the generated micro-seismic event, rewrite the Event table and Wave table, update the waveform information contained in the event, and ensure the integrity of the generated event; If there are no micro-vibration events and no other waveforms trigger within a time interval Δt near the triggering time: write the waveform information into the Unwave table and wait for subsequent judgment; If other waveforms trigger within a time interval Δt near the trigger time but do not generate a microseismic event: query the Unwave table to determine if the number of waveforms triggered within Δt reaches n or more (n is the sensor trigger number threshold, n≥4, and n is 1~2 times the ratio of the maximum sensor spacing to the wave velocity, which can be manually adjusted through monitoring software); if it reaches the threshold, generate a new microseismic event, delete the relevant waveform from the Unwave table, and write it to the Wave table and Event table; if it does not reach the threshold, write the waveform to the Unwave table, and periodically clean up expired waveform information in the Unwave table that did not participate in event generation.

[0036] In one specific embodiment, the system includes a microseismic sensor 1, a wireless microseismic acquisition device 2, an acquisition server 6 (host computer), a communication server, an AP relay module 5, and a communication server 7. The microseismic sensor 1 is connected to the wireless microseismic acquisition device 2 to acquire tunnel microseismic signals and transmit them to the wireless microseismic acquisition device 2. The wireless microseismic acquisition device 2 has a built-in WiFi communication module 3 and at least one LoRa communication module 4 (acquisition device end), which can switch communication modes according to the signal strength of the monitoring environment and communication requirements. In particular, multiple communication methods can be selected for parallel transmission. AP repeater module 5 is deployed as needed in areas with insufficient WiFi signal strength to enhance WiFi signal strength and extend communication distance, ensuring the stability of WiFi communication. LoRa server 7 is used to relay data transmitted by the acquisition instrument via LoRa and forward it to acquisition server 6 in the form of TCP / IP protocol. The host computer software system runs on the acquisition server and integrates waveform robust transmission module 9 and micro-seismic event dynamic generation module 11. Among them, waveform robust transmission module 9 includes a received data verification and response unit 10, which is used to detect the integrity and abnormality of received data and to feed back response signals or abnormal signals to wireless micro-seismic acquisition instrument 2. The received data and response unit are also responsible for completing the data integration work in chronological order according to the predetermined markers, ensuring the correct timing of data under the parallel transmission of multiple communication methods. The micro-seismic event dynamic generation module 11 has an Unwave table, a Wave table, and an Event table, which are used to store waveform information and micro-seismic event information that did not participate in event generation and those that participated in event generation, respectively. The micro-seismic event dynamic generation module 11 also includes a waveform compensation unit 12, which is used to perform waveform compensation operations. Multiple LoRa communication modules 8 in the communication server 7 can all act as slave devices, and can achieve one-to-one communication with the wireless micro-seismic acquisition device 2 (as a LoRa master), which solves the rate bottleneck of multi-acquisition device collaborative transmission and realizes synchronous communication between multiple acquisition devices and the acquisition server 6.

[0037] The system's workflow is as follows: Microseismic sensor 1 collects tunnel microseismic signals in real time, triggering wireless microseismic acquisition device 2 to acquire waveforms; acquisition device 2 first stores the acquired waveform files locally, and then uploads the waveform data to acquisition server 6 according to the selected transmission mode and communication method; if WiFi communication is used and the signal strength is insufficient, the signal is enhanced by AP relay module 5 before transmission; if LoRa communication is used, one-to-one transmission is achieved through LoRa communication module 4 on the acquisition device and the corresponding LoRa communication module 8 (slave) on the communication server; if acquisition device 2 is equipped with multiple LoRa communication modules 4, it transmits in parallel through multiple wireless channels; acquisition server 6 verifies the received waveform data through receiving data verification and response unit 10. If the data is complete and without abnormalities, it sends a response signal, acquisition device 2 deletes the corresponding local waveform file and continues uploading; if the data is abnormal or there is no response, acquisition device 2 resends the waveform data; the microseismic event dynamic generation module 8 of acquisition server 6, based on the received complete waveform data, works collaboratively through a triple information table, and combines with waveform compensation unit 11 to perform waveform compensation operations to dynamically generate complete microseismic events, completing tunnel microseismic monitoring and early warning.

[0038] This system supports three waveform transmission modes, and the specific implementation methods are as follows: (1) Static optimal working mode one: Before the wireless microseismic acquisition instrument 2 is initialized, the signal strength of the current WiFi and LoRa communication methods is detected by the built-in communication module. The transmission rate of each method is estimated based on the signal strength, and the communication method with the best transmission rate is selected. After initialization, this method is used to transmit waveform data. It is suitable for tunnel construction environments with stable conditions and small signal strength fluctuations.

[0039] (2) Static optimal working mode 2: Before each transmission of waveform data, the wireless micro-seismic acquisition instrument 2 detects the signal strength of WiFi and LoRa communication methods in real time, estimates the corresponding transmission rate, dynamically determines the optimal transmission method, and transmits the current waveform data according to the method. It is suitable for tunnel construction environments with complex conditions and large fluctuations in signal strength, and can ensure that the optimal method is used for each transmission.

[0040] (3) Fastest transmission mode: The wireless micro-vibration acquisition instrument 2 detects the signal strength of WiFi and LoRa in real time. When the signal strength of both methods is greater than -80dB (meets the transmission requirements), the current waveform data is divided into packets according to the preset rules. Each packet is assigned a unique transmission mark, and then an idle wireless communication method (WiFi or LoRa) is selected to send the packet data. After the acquisition server 6 receives all the packet data, it integrates the packet data into a complete waveform file according to the transmission mark. It is suitable for scenarios with high transmission rate requirements and stable signal strength, and can maximize transmission efficiency.

[0041] The robust waveform transmission process is as follows: After the micro-vibration sensor 1 is triggered, the wireless micro-vibration acquisition unit 2 immediately acquires the micro-vibration waveform and completes local storage. Then, through the selected transmission working mode and communication method, it uploads the waveform file to the acquisition server 6. After receiving the waveform file, the data receiving verification and response unit 10 of the acquisition server 6 verifies the integrity of the file and checks for data anomalies (such as verifying the file check code, detecting missing or disordered data, etc.). If the verification passes and there are no anomalies, it sends a response signal to the wireless micro-vibration acquisition unit 2. The acquisition unit 2 deletes the waveform file stored locally and continues to upload the next waveform file. If the verification finds data anomalies, or if the acquisition unit 2 does not receive a response signal within 5 seconds, the acquisition unit 2 automatically re-uploads the waveform file until the transmission is successful. Throughout the process, waveform acquisition, local storage, and waveform transmission are carried out synchronously and do not interfere with each other.

[0042] The core process for dynamic generation and waveform recovery of microseismic events is as follows: 1. After receiving the micro-vibration waveform, the acquisition server 6 first stores the waveform data and extracts the acquisition trigger time of the waveform; 2. The acquisition server 6, through the waveform compensation unit 11 of the micro-seismic event dynamic generation module 8, queries the Event table and the Unwave table, and calculates the Δt value using the dynamic value acquisition method, i.e. Calculate using the following formula: ; In the formula, , Number the different sensors; The coordinates of the sensor numbered i; The P-wave velocity of the microseismic event at a certain engineering site; To account for spatial diffraction and geological structure, the path correction parameters are set to a value no less than 0. When the sensor position moves and the coordinates are modified, automatic execution is performed. Correct the calculation to maintain The values ​​are always reasonable.

[0043] 3. Query the Event and Unwave tables to determine the triggering status within a time interval Δt around the triggering time, and execute operations in three branches: (1) Branch 1: If a micro-seismic event has already been triggered within Δt time near the triggering time → perform waveform remediation operation: remediate the newly received waveform into the generated micro-seismic event, rewrite the Event table and Wave table, update the waveform ID, quantity and other information contained in the event, and ensure that the generated event contains all the triggered waveforms to avoid incomplete events due to delayed upload; (2) Branch 2: If there is no micro-seismic event and no other waveform triggers within Δt time near the triggering time, write the waveform information into the Unwave table, wait for other waveforms to be triggered, and then determine whether the micro-seismic event generation conditions are met. (3) Branch 3: If other waveforms are triggered within a time interval Δt near the triggering time but no microseismic event is generated → query the Unwave table, count the number of waveforms triggered within the time interval Δt, and determine whether the conditions for generating a microseismic event are met (number of waveforms ≥ n, n ≥ 4): ①Conditions met: A new microseismic event is generated, all waveforms involved in the event are deleted from the Unwave table and written to the Wave table and Event table, thus completing the generation of the microseismic event; ② If the condition is not met: Write the waveform to the Unwave table and wait for subsequent waveforms to be triggered. At the same time, periodically clean up waveform information in the Unwave table that has been stored for a longer than the preset time and has not participated in the generation of micro-seismic events to avoid data redundancy.

[0044] In the specific implementation process, the value of n can be adjusted according to the sensor spacing of the tunnel project. It is manually set through waveform acquisition and monitoring software, and the adjustment range is 4~8. If it is necessary to improve the source positioning accuracy, the value of n can be appropriately increased, and the number of sensors involved in the calculation can be increased. WiFi communication module 3 supports 2.4G and 5G WiFi 6 networks to ensure the rapid transmission of high-frequency microseismic data near the tunnel face; LoRa communication modules 4 and 9 work together to improve the transmission rate and stability of microseismic data in long-distance areas through one-to-one master-slave inverted communication and multi-module parallel transmission; the dynamic range of Δt is 0.5~2s, which can be adjusted according to the geological conditions of tunnel construction and the propagation speed of microseismic signals; the Unwave table is cleaned periodically every 1~2 hours, and the cleaned objects are waveform information that has been stored for more than the preset time and has not participated in the generation of microseismic events; the local storage of the wireless microseismic acquisition instrument 2 uses non-volatile storage media to ensure that waveform files are not lost after power failure.

[0045] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on its differences from other embodiments. Similar or identical parts between embodiments can be referred to interchangeably. The methods disclosed in the embodiments are described simply because they correspond to the methods disclosed in the embodiments; relevant parts can be found in the method section.

[0046] The above description of the disclosed embodiments enables those skilled in the art to make or use the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. An event robust generation system for wireless microseismic events, characterized by, include: The system comprises a wireless microseismic data acquisition device, a data acquisition server, several microseismic sensors, and a communication server. The wireless microseismic data acquisition device is connected to the microseismic sensors, and the wireless microseismic data acquisition device and the data acquisition server are connected via a multi-mode communication network of the communication server. The wireless microseismic data acquisition device has a built-in communication module that switches communication modes according to preset conditions. The data acquisition server includes a waveform robust transmission module, a microseismic event dynamic generation module, and several communication modules. The waveform robust transmission module includes a received data verification and response unit to realize waveform data verification, response, and retransmission. The microseismic event dynamic generation module has built-in Unwave table, Wave table, and Event table, which work together to dynamically generate microseismic events. The LoRa module of the data acquisition server communicates with the wireless microseismic data acquisition device.

2. The event robust generation system for wireless microseismic events of claim 1, wherein, The communication server includes a WiFi communication module and several LoRa communication modules to realize the parallel transmission of waveform data through multiple wireless channels. The acquisition server integrates the waveform data into a complete waveform according to the packet transmission mark. The communication mode switching preset conditions of the wireless microseismic acquisition instrument are signal strength and data transmission quality. If the WiFi signal strength is lower than the preset threshold, the communication quality is enhanced by adding an AP relay module.

3. The event robust generation system for wireless microseismic events according to claim 1, characterized in that, The micro-seismic event dynamic generation module also includes a waveform recovery unit. The waveform recovery unit is used to query the Event table and the Unwave table. When there is already a micro-seismic event within a time interval Δt near the trigger time of the newly received waveform, the waveform is recovered and added to the generated event, and the Event table and the Wave table are rewritten.

4. The event robust generation system for wireless microseismic events according to claim 1, characterized in that, The dynamic generation of microseismic events adopts... The dynamic value acquisition method determines the time range for event generation based on the sensor's installation location, avoiding repeated searches and improving event generation efficiency while ensuring event integrity.

5. A method for using an event robust generation system for wireless microseismic events, characterized in that, include: The system deploys a microseismic sensor, a wireless microseismic data acquisition device, a communication server, and a data acquisition server. Based on the WiFi signal strength detected by the data acquisition server, an AP repeater module is added to enhance the WiFi signal strength and extend the communication distance. According to signal strength and data transmission speed requirements, a corresponding waveform transmission mode and a corresponding communication mode for the wireless microseismic data acquisition device are selected. After the microseismic sensor triggers the wireless microseismic data acquisition device to collect waveform data, the device first stores the waveform data locally and then uploads the waveform data to the data acquisition server according to the selected transmission mode and communication method. The data acquisition server checks the integrity and anomaly of the received waveform data. If the check is complete and there are no anomalies, it sends a response signal to the data acquisition device, which deletes the corresponding local waveform file and continues uploading the next data. If the check finds data anomalies, or if the data acquisition device does not receive a response signal within 5 seconds, it retransmits the waveform data until the transmission is successful.

6. A method of using the event robust generation system for wireless microseismic events according to claim 5, characterized in that, The local storage includes a power-loss loss storage unit and a power-loss non-loss slow storage unit.

7. A method of using the event robust generation system for wireless microseismic events according to claim 5, characterized in that, The Unwave table records and saves waveforms that did not participate in the generation of microseismic events, the Wave table records and saves waveforms that participated in the generation of microseismic events, and the Event table records and saves the generated microseismic event information. After receiving the waveform file, the acquisition server stores the waveform and extracts the acquisition trigger time; it queries the Event table and Unwave table to determine the triggering situation within a time interval Δt near the trigger time, and performs corresponding operations in coordination with the waveform robust transmission module, specifically as follows: if a microseismic event has already been triggered within a time interval Δt near the trigger time, a waveform remediation operation is performed to remediate the waveform into the generated microseismic event, the Event table and Wave table are rewritten, and the waveform information contained in the event is updated to ensure the integrity of the generated event; If no microseismic event occurs within a time interval Δt near the trigger time and no other waveforms are triggered, the waveform information is written to the Unwave table for further evaluation. If other waveforms are triggered within a time interval Δt near the trigger time but no microseismic event is generated, the Unwave table is queried to determine whether the number of waveforms triggered within the time interval Δt reaches n or more. Here, n is the sensor trigger number threshold, n≥4, and n is 1 to 2 times the ratio of the maximum sensor spacing to the wave velocity. If n or more is reached, a new microseismic event is generated, the relevant waveform is deleted from the Unwave table, and written to the Wave table and the Event table. If the desired time is not reached, the waveform is written to the Unwave table. Then, the Unwave table is cleaned up every 1 to 2 hours for waveform information that has exceeded the preset time and has not participated in the event generation.

8. A method of using the event robust generation system for wireless microseismic events according to claim 7, characterized in that, The The method of determining the coordinates is based on the dynamic value acquisition of the sensor coordinates. Calculate using the following formula: ； in, , Number the different sensors; The coordinates of the sensor numbered i; The P-wave velocity of the microseismic event at a certain engineering site; To account for path correction parameters based on spatial diffraction and geological structure, automatic execution is performed when the sensor position moves and the coordinates are modified. Correct the calculation.

9. A method of using the event robust generation system for wireless microseismic events according to claim 5, characterized in that, The waveform transmission operating modes include: Static optimal working mode 1: Before the data acquisition device is initialized, the signal strength of the current WiFi and LoRa communication methods is detected by the built-in communication module. The transmission rate of each method is estimated based on the signal strength, and the communication method with the best transmission rate is selected. After initialization, this method is used to transmit data. Dynamic Optimal Working Mode 2: Before each waveform data transmission, the data acquisition unit detects the signal strength of both WiFi and LoRa communication methods in real time, estimates the corresponding transmission rate, dynamically determines the optimal transmission method, and transmits the current waveform data according to this method, ensuring that each waveform transmission is in the optimal state. Fastest transmission mode: When the signal strength of each wireless transmission method allows, the waveform data is packetized according to preset rules and assigned a unique transmission marker. The idle wireless communication method is selected to send the waveform data. The acquisition server integrates the packetized waveform data into a complete waveform according to the transmission marker.

10. A method of using the event robust generation system for wireless microseismic events according to claim 5, characterized in that, When the wireless microseismic acquisition device uploads waveform data, it simultaneously sends a checksum of the data. After receiving the waveform data, the acquisition server calculates the checksum of the received data and compares it with the checksum sent by the wireless microseismic acquisition device. If the comparison matches, the waveform data is determined to be complete; if the comparison does not match, the data is determined to be abnormal, triggering the wireless microseismic acquisition device to re-upload.

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