Beidou short message communication node type seismograph based on efficient edge data compression

Abstract

The invention relates to the technical field of seismic exploration, and discloses a Beidou short message communication node type seismograph based on efficient edge data compression, and the seismograph comprises a main control module which is responsible for controlling other modules and cooperating with the other modules to achieve the functions of the other modules; the vibration acquisition module is responsible for acquiring seismic data; the data storage module is used for storing seismic data and configuration parameters during acquisition; and the data compression module is used for compressing the seismic data before the seismic data is transmitted to the satellite. The Beidou short message communication module is used for transmitting the compressed seismic data to a satellite through a Beidou short message; and the power supply module is used for supplying power to other modules. According to the invention, Beidou short message communication and edge data compression are combined, so that the seismograph can realize high-sampling-rate seismic waveform data quasi-real-time transmission in areas without coverage of wireless communication networks such as Wifi and 4G, and therefore, the seismograph can be applied to more complex layout environments and meet the timeliness requirements of seismic monitoring and analysis.

Description

Technical Field

[0001] The present invention relates to the technical field of seismic exploration, and in particular to a Beidou short message communication node-type seismograph based on efficient edge data compression. Background Art

[0002] Seismometers, as essential tools for seismic data collection, are continuously improving in performance driven by technological innovation and the need for increased efficiency. Traditional seismometers fall into two main categories: wired and wireless. Wired seismometers, with their wide bandwidth, high signal-to-noise ratio, and high resolution, are currently the primary acquisition instruments for seismic exploration. However, their need for cable connections makes field deployment difficult, resulting in high construction costs, low exploration efficiency, and difficult maintenance. Wireless seismometers, on the other hand, offer greater flexibility in deployment and acquisition. Early wireless seismometers featured GPS timing and positioning, as well as local data storage. GPS timing provided precise time for data collection, while GPS positioning enabled flexible instrument deployment, eliminating the fixed location requirements of wired instruments. However, early commercial applications had several drawbacks, including the lack of real-time monitoring of seismic data collection, providing timely feedback on data quality and field deployment status. Furthermore, they lacked anti-theft systems, often failing to detect the loss of stations or instrument status until data download was complete. With the development of Wi-Fi and 4G communication technologies, some node-based wireless seismometers have emerged that can transmit real-time earthquake data. These devices acquire real-time data through built-in wireless communication units such as Wi-Fi. However, remote data collection and status monitoring remain difficult in uninhabited areas such as polar regions, deserts, and oceans, where communication is difficult.

[0003] In order to meet the needs of seismic activity monitoring and underground structure exploration in uninhabited areas that are difficult to cover by conventional communication means, the present invention intends to combine a high-compression seismic data compression algorithm and Beidou short message satellite communication technology to achieve low-latency, high-bitrate communication of seismic data in uninhabited areas. Beidou short message satellite communication has the characteristics of high reliability and low latency, and can cover areas that cannot be reached by ground communication networks, including polar and oceanic regions. However, the bit rate of satellite transmission is on the low side, so seismographs with satellite communication functions usually find it difficult to transmit raw seismic data with high time sampling rates (usually above 50Hz) back to the central server, thereby failing to meet the high timeliness requirements of earthquake monitoring. Therefore, the present invention integrates a high-compression seismic data compression algorithm into a seismograph, and utilizes a low-power processing unit in the instrument to achieve data compression at the edge device end. By introducing a seismic data compression algorithm, the data transmission volume of satellite communication per unit time can be increased by several times or even dozens of times, thereby solving the low-bit-rate transmission problem of satellite communication and serving quasi-real-time monitoring and analysis of earthquakes in uninhabited areas. Summary of the Invention

[0004] In order to solve the above technical problems, the present invention provides a Beidou short message communication node seismograph based on efficient edge data compression, which can realize the collection and transmission of high-bitrate seismic data in areas that cannot be covered by traditional 4G, WIFI and other wireless communication technologies, thereby serving the quasi-real-time monitoring and analysis of earthquakes on islands, borders and uninhabited areas.

[0005] In order to solve the above technical problems, the present invention adopts the following technical solutions:

[0006] A BeiDou short message communication node-type seismograph based on efficient edge data compression, including the following modules:

[0007] The main control module is responsible for controlling other modules and cooperating to realize the functions of other modules;

[0008] Vibration acquisition module, responsible for collecting seismic data;

[0009] A data storage module is used to store the collected seismic data and the configuration parameters during collection;

[0010] A data compression module is used to compress seismic data before transmitting it to the satellite;

[0011] Beidou short message communication module, used to transmit compressed seismic data to satellites via Beidou short messages;

[0012] Power module, used to provide power to other modules.

[0013] Furthermore, the vibration acquisition module includes a detector acquisition module and a precise clock module;

[0014] The detector acquisition module includes a three-component dynamic detector, an input protection circuit, a filter circuit, an ADC sampling chip, and a reference voltage chip. The three detectors in the three-component dynamic detector are arranged in the N, E, and Z directions of the measurement coordinate system, with horizontal detectors used in the N and E directions and a vertical detector in the Z direction. The input protection circuit includes a clamping diode and a transient suppression diode. The filter circuit is an RC filter network. The ADC sampling chip receives the reference voltage provided by the reference voltage chip, and the precise clock required by the ADC sampling chip is provided by the precise clock module.

[0015] The precise clock module includes a temperature sensor, a DAC chip, and a voltage-controlled temperature-compensated crystal oscillator. The voltage value is calculated by combining the output of the temperature sensor and the satellite pulse-per-second signal through the temperature-compensated crystal oscillator calibration control algorithm. The voltage value is input into the voltage-controlled temperature-compensated crystal oscillator through the DAC chip to generate a precise clock.

[0016] Furthermore, the data storage module records seismic data through seismic data files and records configuration parameters through acquisition configuration files; the configuration parameters recorded in the acquisition configuration file include station number, number of channels, sampling rate, digital filtering method and compression method; the file header of the seismic data file records satellite information and acquisition configuration file information.

[0017] Furthermore, the data compression module compresses seismic data in the following specific processes: band-pass filtering the original seismic data to remove noise interference that is not within the seismic frequency band; wavelet transforming the band-pass filtered seismic data to decompose the seismic data into multiple sub-bands of different frequencies; quantizing the coefficients of the sub-bands using a clustering algorithm; encoding repeated elements in the quantized seismic data using run-length coding, and then further compressing the elements that appear more frequently in the run-length coded seismic data using Huffman coding.

[0018] Furthermore, the quantization of the sub-band coefficients is achieved by using a clustering algorithm, specifically including: using a k-means++ clustering algorithm to divide the sub-band coefficients into different centroids, and approximately representing all sub-band coefficients divided into the same centroid with the numerical value of the centroid.

[0019] Furthermore, the Beidou short message communication module includes a Beidou short message control module and a GNSS satellite module, and the Beidou short message control module and the GNSS satellite module share a set of satellite antennas; the satellite antenna includes three frequency bands, of which the L band and S band are used for sending and receiving Beidou short messages respectively, and the B1 / L1 band is used for the GNSS services provided by the global positioning system and the Beidou positioning system; the Beidou short message control module provides short message communication functions; the satellite communication control algorithm receives control information from the Beidou short message control module, and packages the compressed seismic data and sends it out through the Beidou short message control module and the satellite antenna; the GNSS satellite module provides pulse number per second signals, timing and positioning functions.

[0020] Furthermore, the power module includes a lithium battery, a power monitoring circuit, a charging control circuit, a Hall switch, a low-noise LDO power supply, a fast transient response DC-DC power supply and an ordinary DC-DC power supply. The Hall switch controls the on and off of the power output of the lithium battery; the low-noise LDO power supply is used to supply the detector acquisition module to achieve the lowest acquisition noise; the fast transient response DC-DC power supply is used to supply the Beidou short message communication module to adapt to the instantaneous power consumption of the Beidou short message communication module during transmission and reception. The remaining modules are powered by an ordinary DC-DC power supply.

[0021] Compared with the prior art, the beneficial technical effects of the present invention are:

[0022] The seismograph designed by the present invention combines Beidou short message communication and edge data compression technologies. The combined application of these two technologies enables the seismograph to achieve quasi-real-time transmission of high-sampling-rate seismic waveform data in areas without wireless communication network coverage such as Wi-Fi and 4G. Therefore, the seismograph can be used in more complex deployment environments and meet the timeliness requirements of earthquake monitoring and analysis. The present invention has the potential to play an important role in vibration monitoring on islands, borders, and uninhabited areas, as well as in geological structure exploration, deep earth exploration, and other application scenarios. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 A schematic diagram of the structural layout of the seismograph of the present invention;

[0024] Figure 2 This is a structural diagram of the vibration collection module of the present invention;

[0025] Figure 3 A schematic structural diagram of a data storage module according to the present invention;

[0026] Figure 4 Schematic diagram of the flow of the multi-stage data compression algorithm of the present invention;

[0027] Figure 5 This is an example diagram of the compression effect of the multi-level data compression algorithm of the present invention on natural earthquake data;

[0028] Figure 6 This is a schematic structural diagram of the Beidou short message communication module of the present invention;

[0029] Figure 7 It is a structural schematic diagram of the power module of the present invention. DETAILED DESCRIPTION

[0030] A preferred embodiment of the present invention will be described in detail below with reference to the accompanying drawings.

[0031] The structural layout of the seismograph of the present invention is as follows Figure 1 As shown, it includes a main control module 1 for coordinating the functions of multiple modules, a data acquisition module 2 responsible for collecting seismic data, a data storage module 3 for storing seismic data, configuration parameters and system logs, a data compression module 4 with seismic data compression function, a Beidou short message communication module 5 that supports Beidou short message communication function, and a power supply module 6 for supplying power to each hardware module.

[0032] The data compression module 4 is a software module, which is controlled by the low-power processing unit of the main control module and provides computing support. The remaining modules are hardware modules. The details of each module of the present invention are introduced below.

[0033] The main control module 1 is the core component of the seismometer, responsible for controlling and processing various functions of the entire device. It uses a 32-bit ultra-low-power microcontroller as its core processor. This core processor enables the main control module to perform functions such as instruction processing, resource management, interface coordination, performance monitoring, and logging for each module.

[0034] like Figure 2 As shown, the vibration acquisition module 2 consists of a detector acquisition module and a precision clock module. The detector acquisition module can be further divided into a three-component dynamic coil detector, an input protection circuit, a filtering circuit, an ADC sampling chip, and a reference voltage chip. The three detectors in the three-component dynamic coil detector are arranged in the N, E, and Z directions, with horizontal detectors used in the N and E directions and a vertical detector in the Z direction. The input protection circuit, consisting of clamping diodes and transient suppression diodes, prevents high voltage generated under abnormal operating conditions from damaging subsequent circuits. The filtering circuit is an RC filter network. The ADC sampling chip receives the reference voltage provided by the reference voltage chip, and the precise clock required by the ADC sampling chip is provided by the precision clock module. The precise clock module includes a temperature sensor, a temperature-compensated crystal oscillator calibration control algorithm, a DAC chip, and a voltage-controlled temperature-compensated crystal oscillator. The temperature-compensated crystal oscillator calibration control algorithm combines the temperature sensor and the satellite pulse-per-second signal (PPS signal) to calculate the appropriate voltage value, which is then controlled by the DAC chip. It is necessary to measure in advance the relationship between the voltage required for the voltage-controlled temperature-compensated crystal oscillator to maintain a stable frequency and the change in temperature. During normal operation, the frequency and phase of the voltage-controlled temperature-compensated crystal oscillator are generally calibrated by the satellite PPS signal. When the satellite signal is weak, the previously measured relationship between the voltage and temperature is used to control the voltage-controlled temperature-compensated crystal oscillator.

[0035] The temperature-compensated crystal oscillator calibration control algorithm described above can employ a PID controller with feedforward, using the relationship between voltage and temperature as feedforward to proactively compensate for the effects of temperature on the crystal oscillator frequency. The feedforward portion calculates the required initial voltage based on the real-time temperature. The feedback portion detects the actual frequency deviation using the PPS signal, and the PID controller further adjusts the output voltage to achieve fine calibration. If the PPS signal is lost, the system relies on feedforward control to ensure frequency stability, switching to temperature compensation mode to maintain the accuracy and stability of the crystal oscillator.

[0036] like Figure 3 As shown, the data storage module 3 uses an SD card to store seismic data files and acquisition configuration files. The acquisition configuration file contains information such as the station number, number of channels, sampling rate, digital filtering method, and compression method. The seismic data file records seismic data, and the file header of the seismic data file records satellite information and information in the acquisition configuration file. The collected seismic data is cached in RAM, written to the data file, and stored on the SD card.

[0037] The data compression module 4 is a software module responsible for compressing seismic data before satellite transmission. In order to improve the compression rate, the present invention combines wavelet transform, cluster quantization, run-length encoding and Huffman encoding to develop a multi-level seismic data compression algorithm. The compression process performed by the data compression module is as follows: Figure 4 As shown in the figure. The original seismic data is first bandpass filtered to remove noise interference that is not within the seismic frequency band. The filtered seismic data is then subjected to a wavelet transform to decompose the seismic data into multiple sub-bands of different frequencies. After determining the wavelet basis function to be used, the seismic data can be represented by a series of sub-band coefficients. A clustering algorithm is then used to quantize the sub-band coefficients, thereby reducing the dynamic range of the seismic data. Specifically, the k-means++ clustering algorithm is used to divide the sub-band coefficients into different centroids, and all sub-band coefficients assigned to the same centroid are approximated by the centroid's numerical value. Run-length encoding is then used to re-encode the repeated elements in the quantized seismic data, and finally Huffman coding is used to further compress the elements that appear more frequently. Figure 5 The data compression module demonstrates an example of compression effect on a typical natural earthquake data. The compression process will produce about 0.8% data error, but can achieve a compression ratio of 11.18 times (that is, the data size is compressed to about 8.9% of the original), thereby greatly improving data transmission efficiency.

[0038] Beidou short message communication module 5 Figure 6 As shown, the system includes a Beidou short message control module and a GNSS satellite module, both of which share a common satellite antenna. The satellite antenna has three frequency bands: the L and S bands are used for sending and receiving Beidou short messages, and the B1 / L1 bands are used for GNSS services provided by the GPS and Beidou positioning systems. The Beidou short message module provides short message communication capabilities and requires a Beidou short message card. The satellite communication control algorithm receives control information from the Beidou short message control module and packages compressed seismic data for transmission via the Beidou short message control module. The GNSS satellite module provides satellite PPS signals, timing, and positioning functions, which are used for clock calibration in the vibration acquisition module and for recording time, latitude, and longitude tags in seismic data files.

[0039] The satellite communication control algorithm described above can use queues for information caching and a master-slave Modbus protocol. The BeiDou short message control module acts as the master device, sending control information or requesting seismic data to the slave device (satellite communication control algorithm). Upon receiving the control information, the satellite communication control algorithm responds to the control instructions or sends back seismic data. Each Modbus data frame contains a device address, a function code, a data field, and a CRC checksum. The function code specifies the operation to be performed, such as reading seismic data or writing control information. The data field contains specific information, and the CRC checksum ensures data integrity.

[0040] The power module 6 is based on lithium battery, equipped with power monitoring circuit and charging control circuit, and the Hall switch controls the opening and closing of the system. Figure 7 As shown in the figure, the charging control circuit can be connected to an external charger or solar panel for extended battery life. During normal operation, the detector acquisition module is powered by a low-noise LDO power supply to minimize acquisition noise. The Beidou short message communication module is powered by a fast transient response DC-DC power supply to accommodate the high instantaneous power consumption during transmission and reception, while minimizing the impact on other circuits. Other circuits are powered by a standard DC-DC power supply.

[0041] Example

[0042] When deploying a seismograph, half-bury it in the designated location. Keep the seismograph level and the detector facing north. An external satellite antenna should be fixed facing the south sky, with an open area in front of the antenna. Depending on the situation, add an external solar panel or a large-capacity battery to ensure battery life. Use a magnetic switch close to the Hall sensor to start the seismograph.

[0043] After starting up, the seismometer automatically checks the lithium battery status, the detector connection, searches for satellite signals, locates and calibrates the clock, calibrates the voltage-controlled temperature-compensated crystal oscillator, configures the BeiDou short message control module, reads the acquisition configuration file, sets acquisition parameters such as the sampling rate, reference voltage, and filtering mode, calibrates the ADC sampling zero point and amplitude, initializes the data compression algorithm, and starts detector acquisition. The seismometer's battery status, self-test results, and satellite signal status are displayed on the LEDs.

[0044] After the acquisition starts, the original signal obtained by the ADC sampling chip is stored in the data file in sequence through the RAM cache. At the same time, the original seismic data is compressed by the data compression module, and then divided, numbered, and packaged into Beidou short message messages through the Beidou short message control module. The Beidou short message is sent to the receiving base station via the Beidou satellite, and then sent to the user via the network by the base station. The user unpacks the Beidou short message, combines the message according to the number, and then runs the decompression algorithm to restore the seismic data.

[0045] When the user needs to modify the acquisition parameters or query the original seismic data of a specific period of time, the base station can send a Beidou short message, which will be forwarded to the seismograph via the Beidou satellite. After receiving the control information, the main control module will make corresponding parameter configuration adjustments or send back the original seismic data fragment specified by the instruction.

[0046] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above and that the invention can be embodied in other specific forms without departing from the spirit or essential characteristics of the invention. Therefore, the embodiments should be considered in all respects as illustrative and non-limiting, and the scope of the invention is defined by the appended claims rather than the foregoing description. It is intended that all variations within the meaning and range of equivalents of the claims be embraced herein, and any reference signs in the claims should not be construed as limiting the claims to which they relate.

[0047] In addition, it should be understood that although this specification is described in terms of implementation methods, not every implementation method contains only one independent technical solution. This narrative method of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment can also be appropriately combined to form other implementation methods that can be understood by those skilled in the art.

Claims

1. A Beidou short message communication node seismograph based on efficient edge data compression, characterized in that: Includes the following modules: The main control module (1) is responsible for controlling other modules and cooperating with them to realize their functions; A vibration collection module (2), responsible for collecting earthquake data; A data storage module (3) is used to store the collected seismic data and the configuration parameters during the collection; A data compression module (4) is used to compress the seismic data before transmitting it to the satellite; A Beidou short message communication module (5), used for transmitting compressed seismic data to a satellite via Beidou short messages; The power module (6) is used to supply power to other modules.

2. The Beidou short message communication node type seismograph based on efficient edge data compression according to claim 1, characterized in that: The vibration acquisition module includes a detector acquisition module and a precise clock module; The detector acquisition module includes a three-component dynamic detector, an input protection circuit, a filter circuit, an ADC sampling chip and a reference voltage chip; the three detectors in the three-component dynamic detector are arranged according to the N, E and Z directions of the measurement coordinate system, the horizontal detectors are used in the N and E directions, and the vertical detector is used in the Z direction; the input protection circuit includes a clamping diode and a transient suppression diode; the filter circuit is an RC filter network; the ADC sampling chip receives the reference voltage provided by the reference voltage chip, and the precise clock required by the ADC sampling chip is provided by the precise clock module; The precise clock module includes a temperature sensor, a DAC chip, and a voltage-controlled temperature-compensated crystal oscillator. The voltage value is calculated by combining the output of the temperature sensor and the satellite pulse number per second signal through the temperature-compensated crystal oscillator calibration control algorithm, and the voltage value is input into the voltage-controlled temperature-compensated crystal oscillator through the DAC chip to generate a precise clock.

3. The Beidou short message communication node type seismograph based on efficient edge data compression according to claim 1, characterized in that: The data storage module records seismic data through seismic data files and records configuration parameters through acquisition configuration files; the configuration parameters recorded in the acquisition configuration files include station number, number of channels, sampling rate, digital filtering method and compression method; the file header of the seismic data file records satellite information and information of the acquisition configuration file.

4. The Beidou short message communication node type seismograph based on efficient edge data compression according to claim 1, characterized in that: The data compression module compresses seismic data in the following process: firstly, the original seismic data is band-pass filtered to remove noise interference that is not within the seismic frequency band; then, the band-pass filtered seismic data is subjected to wavelet transformation to decompose the seismic data into multiple sub-bands of different frequencies; then, a clustering algorithm is used to quantize the coefficients of the sub-bands; then, run-length coding is used to encode the repeated elements in the quantized seismic data, and then Huffman coding is used to further compress the elements that appear more frequently in the run-length coded seismic data.

5. The Beidou short message communication node type seismograph based on efficient edge data compression according to claim 4 is characterized in that: The method of using a clustering algorithm to quantize the coefficients of the subbands specifically includes: using a k-means++ clustering algorithm to divide the subband coefficients into different centroids, and approximately representing all the subband coefficients divided into the same centroid with the value of the centroid.

6. The Beidou short message communication node type seismograph based on efficient edge data compression according to claim 1, characterized in that: The Beidou short message communication module includes a Beidou short message control module and a GNSS satellite module. The Beidou short message control module and the GNSS satellite module share a set of satellite antennas; the satellite antenna includes three frequency bands, wherein the L band and the S band are used for sending and receiving Beidou short messages respectively, and the B1 / L1 band is used for the GNSS services provided by the global positioning system and the Beidou positioning system; the Beidou short message control module provides a short message communication function; the satellite communication control algorithm receives the control information from the Beidou short message control module, and sends the compressed seismic data through the Beidou short message control module and the satellite antenna after packaging; The GNSS satellite module provides pulse-per-second signals, timing and positioning functions.

7. The Beidou short message communication node type seismograph based on efficient edge data compression according to claim 2, characterized in that: The power module includes a lithium battery, a power monitoring circuit, a charging control circuit, a Hall switch, a low-noise LDO power supply, a fast transient response DC-DC power supply, and a common DC-DC power supply. The Hall switch controls the opening and closing of the power output of the lithium battery; the low-noise LDO power supply is used by the detector acquisition module to achieve the lowest acquisition noise; The Beidou short message communication module is supplied by a DC-DC power supply with fast transient response to adapt to the instantaneous power consumption of the Beidou short message communication module during sending and receiving. The other modules are powered by ordinary DC-DC power supplies.

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