A low-power data acquisition method and device based on seismic waveform pre-identification

Abstract

The present invention discloses a low-power data acquisition method and device based on earthquake waveform pre-identification, wherein the method includes: filtering the ground pulsation signal and DC offset value in the original waveform data collected by the vibration sensor through a preset high-pass filter to obtain a pre-processed signal; if the absolute value of the pre-processed signal exceeds the first threshold, a first trigger condition is generated; performing signal separation on the pre-processed signal through a preset low-pass filter to obtain a valid signal; if the amplitude of the valid signal exceeds the second threshold, a second trigger condition is generated; calculating the proportion of the valid signal in the original waveform data through a preset analog division circuit, if the proportion exceeds the third threshold, a third trigger condition is generated; judging whether the three trigger conditions are generated at the same time, if so, waking up the central processor, starting the actual acquisition of the waveform and performing subsequent earthquake waveform recognition and data calculation. The present invention can greatly improve the accuracy of trigger wake-up while reducing power consumption.

Description

Technical Field

[0001] The present invention relates to the technical field of electrical digital data processing, and in particular to a low-power data acquisition method and device based on seismic waveform pre-identification. Background Art

[0002] Current seismic data acquisition equipment includes continuous acquisition type equipment and triggered data acquisition type equipment. For example, traditional seismic data acquisition equipment can collect data in real time under normal power supply conditions, obtain all data, and then select the required data segments for processing. The continuous method can collect all data, but it requires the equipment to run continuously at high power and cannot meet the low power consumption requirements under specific conditions. In addition, because power supply is often not guaranteed in the field, even if solar power is used, there are instabilities and the equipment cannot operate normally.

[0003] Therefore, you can consider waking up the device in sleep mode by vibration or other means, and then the device starts to collect and process event data. However, in the actual environment, there are various vibration interferences, which may cause the device to wake up frequently and fail to achieve the purpose of low power consumption. Due to the large initialization current during the startup process, it may cause the power consumption to increase. Summary of the invention

[0004] In order to solve the above problems, the present invention proposes a low-power data acquisition method and equipment based on seismic waveform pre-identification, which can use simple devices instead of CPU to build a trigger circuit that can pre-identify seismic waveforms, reduce the interference of environmental vibrations, and output a trigger to start the actual processor for post-processing.

[0005] The technical solution adopted by the present invention is as follows:

[0006] On the one hand, the present invention proposes a low-power data acquisition method based on seismic waveform pre-identification, comprising the following steps:

[0007] S1. Filtering the ground pulsation signal and the DC offset value in the original waveform data collected by the vibration sensor through a preset high-pass filter to obtain a preprocessed signal; comparing the absolute value of the preprocessed signal with a first threshold value, and if it exceeds the first threshold value, generating a first trigger condition;

[0008] S2. Separating the preprocessed signal by a preset low-pass filter to obtain a valid signal; comparing the amplitude of the valid signal with a second threshold, and if the amplitude exceeds the second threshold, generating a second trigger condition;

[0009] S3. Calculating the ratio of the effective signal in the original waveform data by a preset analog division circuit, if the ratio exceeds a third threshold, a third trigger condition is generated;

[0010] S4. Determine whether the first trigger condition, the second trigger condition and the third trigger condition occur simultaneously. If so, wake up the central processing unit, start the actual acquisition of the waveform and perform subsequent seismic waveform recognition and data calculation.

[0011] Furthermore, the central processing unit is configured to wake up at a fixed time, collect static waveforms and perform threshold calculations, and obtain the adaptive first threshold, second threshold and third threshold through a digital potentiometer with a latch.

[0012] Furthermore, the calculation method of the first threshold includes: acquiring waveform data within a preset time and performing high-pass filtering, calculating the mean square error after high-pass filtering and obtaining an effective value, and multiplying the voltage value corresponding to the effective value by a preset weight coefficient as the first threshold.

[0013] Furthermore, the calculation method of the second threshold includes: obtaining waveform data within a preset time and performing high-pass filtering and low-pass filtering to obtain signal data within the noise band, then calculating the mean square error and obtaining an effective value, and multiplying the voltage value corresponding to the effective value by a preset weight coefficient as the second threshold.

[0014] Furthermore, the calculation method of the third threshold includes: obtaining waveform data within a preset time and performing high-pass filtering and low-pass filtering, calculating the proportion of the filtered noise band signal in all signals, and multiplying this proportion by a preset weight coefficient as the third threshold.

[0015] On the other hand, the present invention provides a low-power data acquisition device based on seismic waveform pre-identification, comprising:

[0016] A high-pass filter is configured to filter the ground pulsation signal and the DC offset value in the original waveform data collected by the vibration sensor to obtain a preprocessed signal;

[0017] A first comparator is configured to compare the absolute value of the preprocessed signal with a first threshold value, and generate a first trigger condition if the absolute value exceeds the first threshold value;

[0018] A low-pass filter is configured to perform signal separation on the preprocessed signal to obtain a valid signal;

[0019] A second comparator is configured to compare the amplitude of the effective signal with a second threshold value, and generate a second trigger condition if the amplitude exceeds the second threshold value;

[0020] an analog division circuit configured to calculate the proportion of the effective signal in the original waveform data;

[0021] a third comparator configured to compare the ratio with a third threshold value, and generate a third trigger condition if the ratio exceeds the third threshold value;

[0022] The central processing unit is configured to start actual waveform acquisition and perform subsequent seismic waveform recognition and data calculation when the first trigger condition, the second trigger condition and the third trigger condition are generated simultaneously.

[0023] Furthermore, the central processing unit is configured to wake up at a fixed time, collect static waveforms and perform threshold calculations, and obtain the adaptive first threshold, second threshold and third threshold through a digital potentiometer with a latch.

[0024] Furthermore, the central processing unit includes a first threshold calculation unit, which is configured to: obtain waveform data within a preset time and perform high-pass filtering, calculate the mean square error after high-pass filtering and obtain an effective value, and multiply the voltage value corresponding to the effective value by a preset weight coefficient as the first threshold.

[0025] Furthermore, the central processing unit includes a second threshold calculation unit, which is configured to: obtain waveform data within a preset time and perform high-pass filtering and low-pass filtering to obtain signal data within the noise band, then calculate the mean square error and obtain an effective value, and multiply the voltage value corresponding to the effective value by a preset weight coefficient as the second threshold.

[0026] Furthermore, the central processing unit includes a third threshold calculation unit, which is configured to: obtain waveform data within a preset time and perform high-pass filtering and low-pass filtering, calculate the proportion of the filtered noise band signal in all signals, and multiply this proportion by a preset weight coefficient as the third threshold.

[0027] The beneficial effects of the present invention are:

[0028] 1. The present invention adopts a waveform recognition circuit under a variety of trigger judgment conditions to perform pre-trigger judgment on earthquake events; the threshold of the trigger judgment can be calculated by the timed wake-up of the processor to achieve an adaptive threshold.

[0029] 2. The present invention can greatly improve the accuracy of triggering and awakening while reducing power consumption, and can realize the miniaturized design of the equipment, and can be conveniently deployed in various complex environments. The power supply method is also more flexible, and it can be fixedly installed or used in a portable manner, which can greatly reduce its deployment cost. In particular, it can be temporarily deployed in high density after a major earthquake, and it is also more convenient to detect aftershocks. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 It is a schematic diagram of a low-power data acquisition device based on seismic waveform pre-identification according to an embodiment of the present invention.

[0031] Figure 2 It is a principle diagram of a fifth-order high-pass filter according to an embodiment of the present invention.

[0032] Figure 3 It is a principle diagram of a fifth-order low-pass filter according to an embodiment of the present invention.

[0033] Figure 4 It is a structural diagram of a low-power data acquisition device based on seismic waveform pre-identification according to an embodiment of the present invention. DETAILED DESCRIPTION

[0034] In order to have a clearer understanding of the technical features, purposes and effects of the present invention, the specific implementation methods of the present invention are now described. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention, that is, the embodiments described are only part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without making creative work are within the scope of protection of the present invention.

[0035] Environmental interference, such as knocking, nearby activities of cars, people, animals, and rain, is generally of high frequency (significantly greater than 20Hz) or short duration, while the actual earthquake frequency is generally within the range of 0.075Hz to 20Hz. Therefore, a hardware filter can be made based on this feature, and the data before and after the filter are compared with the calm data, and then a trigger wake-up signal is formed through a trigger circuit. In addition, static environmental waveforms can also be collected after the CPU (central processing unit) is started at a fixed time to generate an adaptive threshold for hardware trigger judgment.

[0036] Based on this, this embodiment provides a low-power data acquisition method based on seismic waveform pre-identification, comprising the following steps:

[0037] S1. Filtering the ground pulsation signal and the DC offset value in the original waveform data collected by the vibration sensor through a preset high-pass filter to obtain a preprocessed signal; comparing the absolute value of the preprocessed signal with a first threshold value, and if it exceeds the first threshold value, generating a first trigger condition;

[0038] S2. Separating the preprocessed signal by a preset low-pass filter to obtain a valid signal; comparing the amplitude of the valid signal with a second threshold, and if it exceeds the second threshold, a second trigger condition is generated;

[0039] S3. Calculate the ratio of the effective signal in the original waveform data by a preset analog division circuit. If the ratio exceeds a third threshold, a third trigger condition is generated;

[0040] S4. Determine whether the first trigger condition, the second trigger condition and the third trigger condition are generated at the same time. If so, wake up the central processing unit, start the actual acquisition of the waveform and perform subsequent seismic waveform recognition and data calculation.

[0041] Accordingly, this embodiment also provides a low-power data acquisition device based on seismic waveform pre-identification, such as Figure 1 As shown, including:

[0042] A high-pass filter is configured to filter the ground pulsation signal and the DC offset value in the original waveform data collected by the vibration sensor to obtain a preprocessed signal;

[0043] A first comparator is configured to compare the absolute value of the preprocessed signal with a first threshold value, and generate a first trigger condition if the absolute value exceeds the first threshold value;

[0044] A low-pass filter is configured to perform signal separation on the preprocessed signal to obtain a valid signal;

[0045] A second comparator is configured to compare the amplitude of the effective signal with a second threshold value, and generate a second trigger condition if the amplitude exceeds the second threshold value;

[0046] an analog divider circuit configured to calculate a proportion of a valid signal in the original waveform data;

[0047] a third comparator configured to compare the ratio with a third threshold value, and generate a third trigger condition if the ratio exceeds the third threshold value;

[0048] The central processing unit is configured to start actual waveform acquisition and perform subsequent seismic waveform recognition and data calculation when the first trigger condition, the second trigger condition and the third trigger condition are simultaneously generated.

[0049] Preferably, the high-pass filter can be a multi-order high-pass filter, such as a fifth-order high-pass filter composed of resistors, capacitors and low-power operational amplifiers, such as Figure 2 shown.

[0050] Preferably, the low-pass filter may be a multi-order low-pass filter of about 20 Hz, for example Figure 3 A fifth-order low-pass filter is shown.

[0051] Preferably, the central processing unit is set to wake up at a fixed time, collect static waveforms and perform threshold calculations, and obtain the adaptive first threshold, second threshold and third threshold through a digital potentiometer with a latch.

[0052] More preferably, the central processing unit includes a first threshold calculation unit, which is configured to: obtain waveform data within a preset time and perform high-pass filtering, calculate the mean square error after high-pass filtering and obtain an effective value, and multiply the voltage value corresponding to the effective value by a preset weight coefficient (for example, 5 or 10) as the first threshold.

[0053] More preferably, the central processing unit includes a second threshold calculation unit, which is configured to: obtain waveform data within a preset time and perform high-pass filtering and low-pass filtering to obtain signal data within the noise band, then calculate the mean square error and obtain an effective value, and multiply the voltage value corresponding to the effective value by a preset weight coefficient (for example, 5 or 10) as the second threshold.

[0054] More preferably, the central processing unit includes a third threshold calculation unit, which is configured to: obtain waveform data within a preset time and perform high-pass filtering and low-pass filtering, calculate the proportion of the filtered signal in the noise band in all signals, and multiply this proportion by a preset weight coefficient as the third threshold.

[0055] like Figure 4 As shown, based on this layout, the low-power data acquisition device can be designed compactly to achieve miniaturization of the device. The low-power data acquisition device mainly includes a low-power vibration sensor, an AD converter, a central processing unit, a digital potentiometer with latch, a pre-trigger judgment unit (including multiple comparators, analog dividers, hardware high-pass and low-pass filters, etc., all of which are low-power modules), power management and solar cells. Preferably, the low-power vibration sensor can adopt a low-power MEMS acceleration sensor or a small dynamic coil sensor.

[0056] The above is only a preferred embodiment of the present invention. It should be understood that the present invention is not limited to the form disclosed herein, and should not be regarded as excluding other embodiments, but can be used in various other combinations, modifications and environments, and can be modified within the scope of the concept described herein through the above teachings or the technology or knowledge of the relevant field. The changes and modifications made by those skilled in the art shall not deviate from the spirit and scope of the present invention, and shall be within the scope of protection of the claims attached to the present invention.

Claims

1. A low-power data acquisition method based on seismic waveform pre-identification, characterized in that: The following steps are involved: S1. Filtering the ground pulsation signal and DC offset value in the raw waveform data collected by the vibration sensor through a preset high-pass filter to obtain a preprocessed signal; Comparing the absolute value of the preprocessed signal with a first threshold, and generating a first trigger condition if the absolute value exceeds the first threshold; S2. Separating the preprocessed signal by a preset low-pass filter to obtain a valid signal; comparing the amplitude of the valid signal with a second threshold, and if the amplitude exceeds the second threshold, a second trigger condition is generated; S3. Calculating the ratio of the effective signal in the original waveform data by a preset analog division circuit, if the ratio exceeds a third threshold, a third trigger condition is generated; S4. Determine whether the first trigger condition, the second trigger condition and the third trigger condition occur at the same time. If so, wake up the central processing unit, start the actual acquisition of the waveform and perform subsequent seismic waveform recognition and data calculation; the central processing unit is set to wake up at a fixed time, acquire static waveforms and perform threshold calculations, and obtain the adaptive first threshold, second threshold and third threshold through a digital potentiometer with a latch.

2. A low-power data acquisition method based on seismic waveform pre-identification according to claim 1, characterized in that: The calculation method of the first threshold includes: obtaining waveform data within a preset time and performing high-pass filtering, calculating the mean square error after high-pass filtering and obtaining an effective value, and multiplying the voltage value corresponding to the effective value by a preset weight coefficient as the first threshold.

3. A low-power data acquisition method based on seismic waveform pre-identification according to claim 1, characterized in that: The calculation method of the second threshold includes: obtaining waveform data within a preset time and performing high-pass filtering and low-pass filtering to obtain signal data within the noise band, then calculating the mean square error and obtaining an effective value, and multiplying the voltage value corresponding to the effective value by a preset weight coefficient as the second threshold.

4. A low-power data acquisition method based on seismic waveform pre-identification according to claim 1, characterized in that: The calculation method of the third threshold includes: obtaining waveform data within a preset time and performing high-pass filtering and low-pass filtering, calculating the proportion of the filtered noise band signal in all signals, and multiplying the proportion by a preset weight coefficient as the third threshold.

5. A low-power data acquisition device based on seismic waveform pre-identification, characterized in that: include: A high-pass filter is configured to filter the ground pulsation signal and the DC offset value in the original waveform data collected by the vibration sensor to obtain a preprocessed signal; A first comparator is configured to compare the absolute value of the preprocessed signal with a first threshold value, and generate a first trigger condition if the absolute value exceeds the first threshold value; A low-pass filter is configured to perform signal separation on the preprocessed signal to obtain a valid signal; A second comparator is configured to compare the amplitude of the effective signal with a second threshold value, and generate a second trigger condition if the amplitude exceeds the second threshold value; an analog division circuit configured to calculate the proportion of the effective signal in the original waveform data; a third comparator configured to compare the ratio with a third threshold value, and generate a third trigger condition if the ratio exceeds the third threshold value; The central processing unit is configured to start the actual acquisition of the waveform and perform subsequent seismic waveform recognition and data calculation when the first trigger condition, the second trigger condition and the third trigger condition are generated simultaneously; the central processing unit is set to wake up at a fixed time, acquire static waveforms and perform threshold calculations, and obtain the adaptive first threshold, second threshold and third threshold through a digital potentiometer with a latch.

6. A low-power data acquisition device based on seismic waveform pre-identification according to claim 5, characterized in that: The central processing unit includes a first threshold calculation unit, which is configured to: obtain waveform data within a preset time and perform high-pass filtering, calculate the mean square error after high-pass filtering and obtain an effective value, and multiply the voltage value corresponding to the effective value by a preset weight coefficient as the first threshold.

7. The low-power data acquisition device based on seismic waveform pre-identification according to claim 5, characterized in that: The central processing unit includes a second threshold calculation unit, which is configured to: obtain waveform data within a preset time and perform high-pass filtering and low-pass filtering to obtain signal data within the noise band, then calculate the mean square error and obtain an effective value, and multiply the voltage value corresponding to the effective value by a preset weight coefficient as the second threshold.

8. The low-power data acquisition device based on seismic waveform pre-identification according to claim 5, characterized in that: The central processing unit includes a third threshold calculation unit, which is configured to: obtain waveform data within a preset time and perform high-pass filtering and low-pass filtering, calculate the proportion of the filtered noise band signal in all signals, and multiply this proportion by a preset weight coefficient as the third threshold.

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