WO2021008062A1

WO2021008062A1 - Method and system for multipath spectrum analysis of groove wave signals

Info

Publication number: WO2021008062A1
Application number: PCT/CN2019/121857
Authority: WO
Inventors: 郭银景; 周玉洁; 孙红雨; 吕文红; 丁庆安; 高洁; 陈赓; 王正杰; 陆翔; 孔芳; 刘珍; 牛晨曦; 孟庆良; 刘辉; 杨文健
Original assignee: 山东科技大学
Priority date: 2019-07-17
Filing date: 2019-11-29
Publication date: 2021-01-21
Also published as: CN110501749A; CN110501749B

Abstract

A method and system for the multipath spectrum analysis of groove wave signals (3, 4). A plurality of groove wave signals (3, 4) are obtained by means of transmitting detection signals at different angles, which may achieve the purpose of the multi-directional detection of a target geological interface, increase the range of detection, and reflect more geological information of a formation to be measured. In the extraction of the groove wave signals (3, 4), the groove wave signals (3, 4) are decomposed by using a non-orthogonal decomposition means so as to decompose each multi-path (1, 2) in the groove wave signals (3, 4), and a plurality of echo signals are fused to thereby obtain a multipath spectrum of the groove wave signals (3, 4). The described decomposition means has high decomposition accuracy and is more practical. The decomposed signals may retain as many characteristics of an interface signal as possible, and the obtained signals may be expressed more concisely, thereby improving the signal-to-noise ratio of the signals, reducing the bit error rate of the signals, and improving the accuracy of groove wave detection.

Description

Multipath spectrum analysis method and system of groove wave signal

Technical field

The present disclosure relates to the technical field related to groove wave exploration, and in particular to a method and system for multipath spectrum analysis of groove wave signals.

Background technique

The statements in this section merely provide background information related to the present disclosure, and do not necessarily constitute prior art.

During the propagation of the elastic wave in the formation, due to the unique layering and unevenness of the earth channel, phenomena such as multipath and frequency deviation will be generated, forming a trough wave signal. Analyzing the multipath signal in the trough wave can conduct geological exploration and obtain the distribution of geological layers. In coal mine detection, it is possible to detect faults, collapsed columns, caverns and other geological anomalies in the coal seam in a large range, which plays an important role in the safety production of coal mines. The multipath signals in the groove wave signal are all mixed together. To make full use of the multipath signals in the groove wave, it is necessary to separate the signals. Traditional signal separation and decomposition methods mostly use orthogonal decomposition methods, but in actual situations, the various elements of the signal are not orthogonal. These elements generally have more or less correlations. They are in the performance of random signals. Also plays a key role. Generally, the information of the detection interface can be realized by transmitting elastic wave signals, but the detection range of one transmission is limited, and multi-directional detection cannot be realized.

Summary of the invention

In order to solve the above problems, the present disclosure proposes a groove wave signal multipath spectrum analysis method and system. Multiple groove wave signals are obtained by transmitting detection signals at different angles, which can achieve the purpose of multi-directional detection of the target geological interface and increase the detection Scope, more geological information of the formation to be measured is reflected. In the aspect of trough wave signal extraction, the trough wave signal is decomposed by a non-orthogonal decomposition method to decompose each multipath in the trough wave signal, and multiple echo signals are generated Fusion, thereby obtaining the multipath spectrum of the groove signal. This decomposition method has high decomposition accuracy and is more practical. The decomposed signal can retain as many characteristics of the interface signal as possible, and the obtained signal can be expressed more concisely, thereby improving the signal-to-noise ratio of the signal, reducing the signal error rate, and improving the accuracy of groove wave detection.

In order to achieve the above objectives, the present disclosure adopts the following technical solutions:

One or more embodiments provide a multipath spectrum analysis method of a groove wave signal, including the following steps:

Transmit elastic wave detection signals to the ground under test at multiple different angles, and receive multiple groove wave signals after being reflected by the ground under test;

Decompose each trough wave signal to obtain the multipath signal of each interface returned by different paths;

All the multipath signals decomposed from each groove wave signal are fused to obtain the multipath spectrum of the groove wave signal.

A groove wave signal multipath spectrum analysis system, including a groove wave signal detection device, a data acquisition module, a groove wave signal decomposition module and a fusion module;

Trough wave signal detection device: used to transmit elastic wave detection signals to the ground under test at multiple different angles, and receive multiple groove wave signals after being reflected by the ground under test;

The data acquisition module is connected to the groove wave signal detection device, and is used to send the detected angle data and the echo signal received by the receiver of the groove wave signal detection device;

Slot wave signal decomposition module: used to decompose each slot wave signal to obtain multipath signals of various interfaces returned by different paths;

Fusion module: It is used to fuse all the obtained multipath signals according to the groove signal obtained each time and decompose the obtained multipath signal to obtain the multipath spectrum of the groove signal.

An electronic device includes a memory, a processor, and computer instructions stored on the memory and running on the processor. When the computer instructions are executed by the processor, the steps described in the above method are completed.

A computer-readable storage medium for storing computer instructions, which, when executed by a processor, complete the steps described in the above method.

The method of the present disclosure for transmitting detection signals at multiple angles can obtain more geological information. When the detection signals are transmitted at multiple different angles, the reflected interface may be different, thereby expanding the range of the detection stratum and allowing a more comprehensive response. The condition of the formation, so as to obtain as many interface signals as possible. It can achieve the purpose of multi-directional detection of the target geological interface, increase the detection range, and more reflect the geological information of the ground to be measured.

Compared with the prior art, the beneficial effects of the present disclosure are:

(1) The present disclosure obtains multiple trough wave signals by transmitting detection signals from different angles, which can achieve the purpose of multi-directional detection of the target geological interface, increase the detection range, and more reflect the geological information of the formation to be measured.

(2) The present disclosure uses a non-orthogonal decomposition method to decompose the slot wave signal, decompose each multipath in the slot wave signal, and merge multiple echo signals to obtain the multipath spectrum of the slot wave signal. This decomposition method has high decomposition accuracy and is more practical. The decomposed signal can retain as many characteristics of the interface signal as possible, and the obtained signal can be expressed more concisely, thereby improving the signal-to-noise ratio of the signal, reducing the signal error rate, and improving the accuracy of groove wave detection.

Description of the drawings

The drawings of the specification forming a part of the present disclosure are used to provide a further understanding of the present disclosure, and the exemplary embodiments and descriptions of the present disclosure are used to explain the present disclosure, and do not constitute a limitation to the present disclosure.

FIG. 1 is a flowchart of the method of Embodiment 1 of the present disclosure;

FIG. 2 is a schematic diagram of a trough wave signal obtained by a single transmission signal in an example of Embodiment 1 of the present disclosure;

FIG. 3 is a schematic diagram of obtaining a groove wave signal by transmitting signals at two different angles in an example of Embodiment 1 of the present disclosure;

FIG. 4 is a path-delay spectrum in a multipath spectrum obtained by example in Embodiment 1 of the present disclosure;

Fig. 5 is a path-amplitude spectrum in a multipath spectrum obtained by an example of embodiment 1 of the present disclosure;

Among them: 1. The first multipath generated by a single transmission signal; 2. The second multipath generated by a single transmission signal; 3. The slot wave signal received by the first transmission; 4. The slot wave signal received by the second transmission. , 5. Detection device for groove wave signal.

Detailed ways:

The disclosure will be further described below in conjunction with the drawings and embodiments.

It should be pointed out that the following detailed descriptions are all exemplary and are intended to provide further description of the present disclosure. Unless otherwise indicated, all technical and scientific terms used herein have the same meaning as commonly understood by those of ordinary skill in the technical field to which this disclosure belongs.

It should be noted that the terms used here are only for describing specific embodiments, and are not intended to limit the exemplary embodiments according to the present disclosure. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should also be understood that when the terms "comprising" and/or "including" are used in this specification, they indicate There are features, steps, operations, devices, components, and/or combinations thereof. It should be noted that the various embodiments in the present disclosure and the features in the embodiments can be combined with each other if there is no conflict. The embodiments will be described in detail below in conjunction with the drawings.

Explanation of related technical terms:

Multipath: The elastic wave signal transmitted each time is a beam, which will reach the receiving point through different paths to form a slot wave. Each path signal in different paths is called a multipath signal.

Slot wave signal: It is formed in the stratum. After one launch, the final mixed signal received is called the slot wave signal.

Multipath spectrum: It is a signal map formed by fusion of multiple multipaths (including transmitted from different angles), which are two maps of path-amplitude and path-delay.

Example 1

In the field of wireless communications, multipath refers to the propagation of radio signals from the transmitting antenna to the receiving antenna through multiple paths. Each signal arriving at the receiving antenna from different paths is called a multipath signal. The groove wave signal is formed by mixing various multipath signals.

The groove wave signal detection device 5 includes a transmitter and a receiver. The transmitter is used to transmit a detection signal. After the transmitted detection signal is reflected by the geological interface in the formation, the receiver receives a mixed signal of multiple path signals, that is, the groove wave signal.

In the technical solutions disclosed in one or more embodiments, as shown in FIG. 1, a multipath spectrum analysis method of a groove wave signal includes the following steps:

Step 1. Transmit elastic wave detection signals to the ground under test at multiple different angles, and receive multiple groove wave signals after being reflected by the ground under test;

The formation to be tested may be a coal seam to be tested, a mineral (oil, natural gas, water) formation, etc. By emitting detection signals from different angles, more geological information can be obtained.

Step 2. Decompose each slot wave signal to obtain the multipath signals of each interface returned by different paths;

Step 3. Fusion of all the multipath signals obtained in step 2 to obtain the multipath spectrum of the groove wave signal

In the step 1, a groove wave signal can be obtained by transmitting an elastic wave detection signal, and each groove wave contains multiple echo signals reflected from different paths, so that multiple information on different reflection interfaces can be obtained. Each echo signal is a multipath signal. Change the launch angle of the transmitter, and use the same method to detect the information on the interface of another part of the target formation. The paths of multipaths generated by launching at an angle are different, but the paths of different multipaths at different angles may also be the same. For example, the first multipath at angle 1 and the second multipath at angle 2 pass through The paths are coincident. The multi-angle emission method expands the range of the ground to be detected, and can more comprehensively reflect the situation of the ground, so as to obtain as many signals of the target interface as possible. It can achieve the purpose of multi-directional detection of the target geological interface, increase the detection range, and more reflect the geological information of the ground to be measured.

Transmit elastic wave detection signals to the ground under test at multiple different angles, and receive multiple groove wave signals after being reflected by the ground under test, and the sequence of each groove wave signal obtained is:

Where N represents the multipath, S _i represents the i-th signal path.

As a further improvement, the step 2 specifically generates different degrees of signal delay and energy attenuation according to each multipath signal in the groove signal, and decomposes the groove signal.

The method of decomposing the trough wave signal can adopt the non-orthogonal decomposition method to decompose each multipath.

The method of using non-orthogonal decomposition method to decompose the trough wave signal includes the following steps:

Step 21: Set a non-orthogonal basis according to the frequency of the multipath signal to obtain a non-orthogonal basis sequence;

Step 22: After decomposing a series of non-orthogonal basis sequences, according to the non-orthogonal basis sequences, the non-orthogonal basis is periodically expanded to reconstruct the mixed independent components in the original groove wave signal, and each independent component is a multiple径signal.

Setting the non-orthogonal basis according to the frequency of the multipath signal is specifically as follows: firstly, the signal with the lowest frequency in the current groove signal is obtained as the first basis, and then the second low frequency signal is separated from the groove signal as the second basis. Until all possible bases are separated, a non-orthogonal base sequence is obtained.

Step 3. Fusion of the multipath signals of each interface obtained in step 2 to obtain a multipath spectrum of the groove wave signal.

Fuse the obtained multipath signals of each interface to obtain the multipath spectrum of the groove wave signal, specifically: extract the amplitude of each multipath signal, obtain the path-amplitude spectrum according to different paths; or extract the time of each multipath signal Delay data, and obtain path-delay graphs according to different paths.

The fusion of multiple echo signals can get the multipath spectrum of the signal, which can be divided into two specifically, one is the path-amplitude spectrum, which reflects the different amplitude of each path; the other is the path-delay graph , The delay of different paths is different.

The following is a specific example for description.

As shown in Fig. 2, the groove wave signal detection device 5, in this embodiment, transmits the detected signal at one time.

In this embodiment, two multipaths are generated in each transmission as an example. The paths of the two multipath signals are represented by solid lines and dashed lines respectively. The interface information detected at these two locations is detected by elastic wave signals emitted in the same direction. of.

In actual detection, the elastic wave emitted in the same direction each time is a beam, and the outward divergence can form multiple paths. After the elastic wave of each path is reflected, a variety of different geological structure information can be detected. Not just two. This embodiment ideally models the detection result to illustrate the principle.

As shown in Fig. 2, the groove signal detection device 5 obtains multiple groove signals according to the method in step 1. This embodiment takes two detection points as an example, where 1 represents the detected echo of the first part of the interface The signal is the first multipath 1 generated by a single transmission signal, and 2 represents the echo signal of the detected second part of the interface, that is, the second multipath 2 generated by a single transmission signal. Both interface information It is detected by the same transmission signal. The difference is that the two pieces of information are not on the same geological structure. The echo signal received in this transmit signal contains the mixed information of the two parts of the signal, that is, the trough wave signal, and its multipath phase will continue to change along with the geological structure interface.

As shown in Figure 3, the solid line and the dashed line respectively represent two elastic wave emission signals with different angles. Among them, 3 represents the groove echo signal received in one transmission, that is, the groove signal received in the first transmission 3. 4 represents the groove echo signal received after changing the transmission angle, that is, the groove received in the second transmission. Wave signal 4. Among them, 3 contains echo signals of multiple paths, and 4 also contains echo signals of multiple paths.

Similarly, by changing the angle again, another part of the target geological information can be obtained, so as to achieve the purpose of multi-directional detection of the target geological interface. The trough wave signal received by the receiver each time is subjected to non-orthogonal decomposition to separate each multipath, and then multiple echo signals are fused to obtain the multipath spectrum of the trough wave signal. As shown in Figures 4 and 5, the obtained multipath spectrum is the path-amplitude spectrum and the path-delay spectrum, and the curve is the envelope. Since the number of multipaths is infinite in actual situations, the obtained multipath spectrum can be regarded as continuous. The same launch angle will go through different paths, and the amplitude and time delay of the echo signal will be different. Of course, different launch angles have different paths. The multipath spectrum can clearly indicate the amplitude and time delay of the multipath signal of different paths, and the multipath spectrum only contains the signal returned by the target interface, which eliminates the interference of other interface signals, and is more conducive to the basis of the obtained multipath signal. The path spectrum signal is used for geological analysis of the target interface.

The present disclosure uses a non-orthogonal decomposition method to decompose the trough wave signal, decompose each multipath in the trough wave signal, and merge multiple echo signals to obtain the multipath spectrum of the trough wave signal. This decomposition method has high decomposition accuracy and is more practical. The decomposed signal can retain as many characteristics of the interface signal as possible, and the obtained signal can be expressed more concisely, thereby improving the signal-to-noise ratio of the signal, reducing the signal error rate, and improving the accuracy of groove wave detection.

Example 2

This embodiment provides a groove wave signal multipath spectrum analysis system, which includes a groove wave signal detection device, a data acquisition module, a groove wave signal decomposition module, and a fusion module;

Fusion module: used to fuse all the obtained multipath signals according to the multipath signal obtained by decomposing the groove wave signal obtained each time to obtain the multipath spectrum of the groove wave signal.

Example 3

This embodiment provides an electronic device, including a memory, a processor, and computer instructions stored on the memory and running on the processor. When the computer instructions are executed by the processor, the steps described in the method in Embodiment 1 are completed.

Example 4

This embodiment provides a computer-readable storage medium for storing computer instructions. When the computer instructions are executed by a processor, the steps described in the method of Embodiment 1 are completed.

The foregoing descriptions are only preferred embodiments of the present disclosure, and are not intended to limit the present disclosure. For those skilled in the art, the present disclosure may have various modifications and changes. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present disclosure shall be included in the protection scope of the present disclosure.

Although the specific embodiments of the present disclosure are described above in conjunction with the accompanying drawings, they do not limit the scope of protection of the present disclosure. Those skilled in the art should understand that on the basis of the technical solutions of the present disclosure, those skilled in the art do not need to make creative efforts. Various modifications or variations that can be made are still within the protection scope of the present disclosure.

Claims

A method for analyzing multipath spectrum of groove wave signal, which is characterized in that it comprises the following steps:

Transmit elastic wave detection signals to the ground under test at multiple different angles, and receive multiple groove wave signals after being reflected by the ground under test;

Decompose each trough wave signal to obtain the multipath signal of each interface returned by different paths;

The obtained multipath signals of each interface are fused to obtain the multipath spectrum of the groove wave signal.
The multipath spectrum analysis method of a slot wave signal according to claim 1, characterized in that: each slot wave signal is decomposed, specifically according to the signal delay and energy attenuation generated by each multipath signal in the slot wave signal , To decompose the trough wave signal.
The multipath spectrum analysis method of a groove wave signal according to claim 1, wherein the non-orthogonal decomposition method is used to decompose each groove wave signal.
The multipath spectrum analysis method of a groove wave signal according to claim 3, characterized in that: each groove wave signal is decomposed using a non-orthogonal decomposition method, and the steps include:

Set the non-orthogonal basis according to the frequency of the multipath signal to obtain the non-orthogonal basis sequence;

According to the non-orthogonal basis sequence, the non-orthogonal basis is periodically expanded to reconstruct the mixed independent components in the original trough wave signal, and each independent component is a multipath signal.
The method for analyzing multipath spectrum of a groove signal according to claim 4, characterized in that: setting the non-orthogonal basis according to the frequency of the multipath signal is specifically: firstly obtaining the lowest frequency signal in the current groove signal as The first base is then separated from the slot wave signal and the second low-frequency signal is used as the second base until all possible bases are separated to obtain a non-orthogonal base sequence.
The groove wave signal multipath spectrum analysis method according to claim 1, characterized in that: the obtained multipath signals of each interface are fused to obtain the groove wave signal multipath spectrum, which is specifically the extraction of each multipath signal Amplitude, obtain path-amplitude spectrum according to different paths.
The groove wave signal multipath spectrum analysis method according to claim 1, characterized in that: the obtained multipath signals of each interface are fused to obtain the groove wave signal multipath spectrum, which is specifically the extraction of each multipath signal Delay data, obtain path-delay graphs according to different paths.
A groove wave signal multipath spectrum analysis system, which is characterized by: a groove wave signal detection device, a data acquisition module, a groove wave signal decomposition module and a fusion module;

Trough wave signal detection device: used to transmit elastic wave detection signals to the ground under test at multiple different angles, and receive multiple groove wave signals after being reflected by the ground under test;

The data acquisition module is connected to the groove wave signal detection device, and is used to send the detected angle data and the echo signal received by the receiver of the groove wave signal detection device;

Slot wave signal decomposition module: used to decompose each slot wave signal to obtain multipath signals of various interfaces returned by different paths;

Fusion module: used to fuse all the obtained multipath signals according to the multipath signal obtained by decomposing the groove wave signal obtained each time to obtain the multipath spectrum of the groove wave signal.
An electronic device, which is characterized by comprising a memory and a processor, and computer instructions stored in the memory and running on the processor, and when the computer instructions are executed by the processor, they complete the method described in any one of claims 1-7. The steps described.
A computer-readable storage medium, characterized in that it is used to store computer instructions, which, when executed by a processor, complete the steps described in any one of the methods of claims 1-7.