Shallow stratum profile data processing method and system for envelope signals

Abstract

The invention provides a shallow stratum profile data processing method and system for envelope signals, and the method comprises the steps: S1, carrying out the Hilbert transformation processing of obtained stratum profile data, and obtaining an analysis signal; s2, obtaining an envelope signal by calculating the amplitude of the analysis signal; s3, performing differential operation on the envelope signal to obtain a differential form of the envelope signal; and S4, performing negative value return-to-zero operation on the differential form of the envelope signal to obtain a final processing signal. According to the scheme, the difference is calculated on the basis of the envelope signal, the negative value is returned to zero, another display effect can be obtained, and the display resolution of the stratum detection profile is improved visually.

Description

Technical Field

[0001] The embodiments of the present invention relate to the technical field of seabed exploration, and particularly to a method and system for processing sub-bottom profile data for envelope signals. Background Art

[0002] A sub-bottom profiler emits a scanning signal with a modulation frequency range of about 1 kHz to about 20 kHz to detect the geological structure below the water bottom. It has high performance in terms of formation resolution and formation penetration depth, and can obtain sub-bottom profile data with a vertical resolution of centimeters to decimeters. At the seabed, the targets that people want to detect may be buried several meters deep, and a sub-bottom profiler with a frequency of several kilohertz is very useful for locating these underground targets. Traditional chirp SBP systems usually generate only the envelope part represented by positive polarity, which uses the Hilbert transform. This approach essentially improves the visual signal-to-noise ratio of the profile by sacrificing resolution.

[0003] The core idea of the Hilbert transform is to convolve a real-valued function with a complex-valued function to obtain the analytic function of the signal. The analytic function has the property of being holomorphic and can be expressed in the form of a real part and an imaginary part. The real part is the real-valued function itself, and the imaginary part is the Hilbert transform of the real-valued function. The analytic function (signal) has the following properties:

[0004] (1) The power spectra of the real part and the imaginary part are the same;

[0005] (2) The autocorrelation functions of the real part and the imaginary part are the same;

[0006] (3) The cross-correlation function of the real part and the imaginary part is an odd function;

[0007] (4) The spectrum of the analytic signal has only the positive frequency band, and the amplitude becomes twice the original (realizing the transformation from a bilateral spectrum to a unilateral spectrum);

[0008] (5) The power spectrum of the analytic signal also has only the positive frequency band, and the intensity becomes four times the original.

[0009] An important application of the Hilbert transform is to extract the envelope information of the signal. Generally speaking, the envelope of a signal refers to the change trend on a long time scale, reflecting the overall characteristics of the signal. And the amplitude spectrum of the analytic signal represents the envelope information of the real-valued signal. Displaying the sub-bottom profile detection results in the form of the Hilbert amplitude envelope easily leads to problems such as low visual resolution and chaotic reflection wave groups in areas with complex formation structures. Summary of the Invention

[0010] In view of this, an embodiment of the present invention provides a method and system for processing shallow stratigraphic profile data for envelope signals. The present invention aims to solve the problems of low visual resolution and chaotic reflection wave groups in the detection results of shallow stratigraphic profiles in areas with complex stratigraphic structures.

[0011] According to the first aspect of the embodiments of the present invention, there is provided a method for processing shallow stratigraphic profile data for envelope signals, including: Step S1, performing Hilbert transform processing on the acquired stratigraphic profile data to obtain an analytic signal; Step S2, calculating the amplitude of the analytic signal to obtain an envelope signal; Step S3, performing a difference operation on the envelope signal to obtain a differential form of the envelope signal; Step S4, performing a negative value zeroing operation on the differential form of the envelope signal to obtain a final processed signal.

[0012] In one implementation, the stratigraphic profile data of each trace can be expressed as a real-valued sequence:

[0013] s i (t j ), i = 1, 2, 3, …, n; j = 1, 2, 3, …, m

[0014] where s i (t j ) represents the real value of the i-th trace of stratigraphic profile data, and each trace has m sampling points.

[0015] In another implementation, the analytic signal can be expressed as:

[0016]

[0017] where H[s i (t j )] is the Hilbert transform of s i (t j ).

[0018] In another implementation, the envelope signal can be expressed as:

[0019]

[0020] The differential form of the envelope signal can be expressed as:

[0021]

[0022] In another implementation, performing a negative value zeroing operation on the differential form of the envelope signal specifically means zeroing the difference that is negative:

[0023] {d i (t j ) < 0} = 0.

[0024] According to the second aspect of the embodiments of the present invention, a shallow stratum profile data processing system for envelope signals is provided, including: an analytical signal module for performing Hilbert transform processing on the acquired stratum profile data to obtain an analytical signal; an envelope signal module for obtaining an envelope signal by calculating the amplitude of the analytical signal; a differential operation module for performing a differential operation on the envelope signal to obtain a differential form of the envelope signal; and a negative value zeroing operation module for performing a negative value zeroing operation on the differential form of the envelope signal to obtain a final processed signal.

[0025] According to the third aspect of the embodiments of the present invention, an electronic device is provided, including a processor and a memory storing a program. Among them, the program includes instructions that, when executed by the processor, cause the processor to perform the steps executed by the method in the first aspect as described above.

[0026] According to the fourth aspect of the embodiments of the present invention, a computer storage medium is provided, on which a computer program is stored, and when the program is executed by a processor, it implements the method in the first aspect as described above.

[0027] The solution of the present invention can process the envelope signals recorded by a shallow stratum profiler, improve the visual resolution, and further improve the display effect of the stratum profile for use by geological interpreters. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the drawings in the following description are only some embodiments recorded in the embodiments of the present invention, and those of ordinary skill in the art can also obtain other drawings based on these drawings.

[0029] Figure 1 It is a step flow chart of a method for processing shallow stratum profile data for envelope signals according to the present invention;

[0030] Figure 2 It is a display effect diagram of the Hilbert amplitude envelope of a certain actual stratum profile detection data;

[0031] Figure 3 It is a schematic diagram of the display effect of a classical seismic profile;

[0032] Figure 4 It is a schematic diagram of the display effect after processing using the method of the present invention;

[0033] Figure 5 It is a schematic diagram of the display effect after changing the color scheme after processing using the method of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0034] For a clearer understanding of the technical features, objectives, and effects of the embodiments of the present invention, the specific implementation manners of the embodiments of the present invention will now be described with reference to the accompanying drawings.

[0035] In this document, "exemplarily" means "serving as an instance, example, or illustration", and any illustration or implementation manner described as "exemplarily" in this document should not be interpreted as a more preferred or more advantageous technical solution.

[0036] To enable those skilled in the art to better understand the technical solutions in the embodiments of the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments in the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art shall fall within the protection scope of the embodiments of the present invention.

[0037] The present invention is applicable to processing any kind of formation profile detection data that is approximately self-exciting and self-receiving, regardless of the signal type, including frequency-modulated signals (Chirp), sine signals (CW, continuous wave), and pulse signals (spark or Boomer sources). For frequency-modulated signals and sine signals, it is applicable after performing correlation processing on the original signal and taking the Hilbert amplitude envelope. For pulse signals, it is applicable after performing predictive deconvolution and pulse deconvolution on the original signal. The algorithm proposed by the present invention is applicable to the post-processing of shallow formation profile data and is also applicable to being integrated into on-site data acquisition software to achieve real-time processing of detection data.

[0038] Taking the working process of a Chirp-type shallow formation profiler as an example, the sound source emits a frequency-modulated acoustic wave towards the bottom of the water. After the acoustic wave encounters the reflection interface of the seabed and the underlying formation, a reflected wave is formed and propagates upward, which is received and recorded by the hydrophone. The recorder usually needs to perform correlation (matching) processing on the reflected signal in combination with the signal characteristics of the transmitted signal to obtain a relatively intuitive formation profile to help users obtain useful information.

[0039] To improve the display effect of formation profile detection data, a mainstream approach in the industry is to perform Hilbert transform on the data after correlation processing to obtain the so-called analytical signal, and present the amplitude spectrum of the analytical signal as the detection result to the user. During the navigation of the survey ship, data is continuously collected to form a formation profile diagram.

[0040] The specific implementation of the embodiments of the present invention will be further described below in conjunction with the accompanying drawings of the embodiments of the present invention.

[0041] See Figures 1 - 5 , the method of the present invention mainly includes the following steps:

[0042] Step S1: Perform Hilbert transform on the acquired formation profile data to obtain the analytic signal;

[0043] Step S2: Calculate the amplitude of the analytic signal to obtain the envelope signal;

[0044] Step S3: Perform a difference operation on the envelope signal to obtain the difference form of the envelope signal;

[0045] Step S4: Perform a negative value zeroing operation on the difference form of the envelope signal to obtain the final processed signal. Specifically, the formation profile data of each Ping (trace) can be expressed as a real-valued sequence:

[0046] s i (t j ), i = 1, 2, 3, …, n; j = 1, 2, 3, …, m

[0047] where s i (t j ) represents the real value of the formation profile data of the i-th trace, and each trace has m sampling points.

[0048] The analytic signal can be expressed as:

[0049]

[0050] where H[s i (t j )] is the Hilbert transform of s i (t j ).

[0051] The amplitude spectrum of the analytic signal, i.e., the envelope signal, can be expressed as:

[0052]

[0053] The difference form of the envelope signal can be expressed as:

[0054]

[0055] Performing a negative value zeroing operation on the difference form of the envelope signal specifically means zeroing the differences that are negative:

[0056] {d i (t j ) < 0} = 0.

[0057] For the self-exciting and self-receiving formation profile detection data, taking the Hilbert amplitude envelope of the reflection signal is a commonly used method to enhance the display effect. The technical solution proposed by the present invention is to calculate the difference based on the envelope signal and set the negative values to zero, which can obtain another display effect, visually improve the display resolution of the formation detection profile, and solve the problems of low visual resolution and chaotic reflection wave groups in the shallow formation profile detection results in areas with complex formation structures.

[0058] The method proposed by the present invention has been applied to the data processing of multiple actual cases. See Figures 3 - 5 for the application effects of the shallow formation profile data collected by the American EdgeTech 3100P and 216 towed fish. Figure 5 The color scheme mentioned refers to the commonly used color scheme of the SES series parametric array shallow profiles of the German Innomar company.

[0059] The embodiment of the present invention also provides a shallow formation profile data processing system for envelope signals, including:

[0060] An analytical signal module for performing Hilbert transform processing on the obtained formation profile data to obtain an analytical signal;

[0061] An envelope signal module for obtaining an envelope signal by calculating the amplitude of the analytical signal;

[0062] A difference operation module for performing a difference operation on the envelope signal to obtain a difference form of the envelope signal;

[0063] A negative value zeroing operation module for performing a negative value zeroing operation on the difference form of the envelope signal to obtain a final processed signal.

[0064] It should be understood that the shallow formation profile data processing system for envelope signals in this embodiment is used to implement the corresponding methods in the foregoing multiple method embodiments and has the beneficial effects of the corresponding method embodiments.

[0065] As another example, the present invention also provides an electronic device, which is an example of a hardware device that can be applied to various aspects of the present invention. The electronic device is intended to represent various forms of digital electronic computer devices, such as, portable computers, desktop computers, workstations, personal digital assistants, servers, blade servers, mainframe computers, and other suitable computers. The electronic device can also represent various forms of mobile devices, such as, personal digital processing, cellular phones, smart phones, wearable devices, and other similar computing devices. The components shown herein, their connections and relationships, and their functions are only examples and are not intended to limit the implementation of the present invention described herein and / or claimed.

[0066] The electronic device may include: a processor, a communications interface, a memory, and a communication bus.

[0067] The processor, the communications interface, and the memory communicate with each other via the communication bus. The communications interface is used to communicate with other electronic devices or servers.

[0068] The processor is used to execute a program, and specifically may execute the relevant steps in the above method embodiments.

[0069] Specifically, the program may include program code, and the program code includes computer operation instructions.

[0070] The processor may be a central processing unit (CPU), or a specific integrated circuit (ASIC), or one or more integrated circuits configured to implement the embodiments of the present invention. One or more processors included in the intelligent device may be of the same type of processor, such as one or more CPUs; or may be of different types of processors, such as one or more CPUs and one or more ASICs.

[0071] The memory is used to store the program. The memory may include high-speed RAM memory, and may also include non-volatile memory, such as at least one disk memory.

[0072] When the program is executed by the processor, it is used to cause the electronic device to execute a method for processing shallow subsurface profile data for an envelope signal. Step S1: Perform Hilbert transform processing on the acquired subsurface profile data to obtain an analytic signal; Step S2: Obtain an envelope signal by calculating the amplitude of the analytic signal; Step S3: Perform a difference operation on the envelope signal to obtain a differential form of the envelope signal; Step S4: Perform a negative value zeroing operation on the differential form of the envelope signal to obtain a final processed signal.

[0073] In addition, for the specific implementation of each step in the program, reference may be made to the corresponding steps and descriptions in the corresponding units in the above method embodiments, which will not be elaborated here. Those skilled in the art can clearly understand that for the convenience and brevity of description, the specific working processes of the above-described devices and modules may refer to the corresponding process descriptions in the foregoing method embodiments, which will not be repeated here.

[0074] An exemplary embodiment of the present invention also provides a computer storage medium storing a computer program, wherein when the computer program is executed by a processor, it implements the methods of the embodiments of the present invention. Reference may be made to the corresponding process descriptions in the foregoing method embodiments, which will not be repeated here.

[0075] The method according to an embodiment of the present invention can be implemented in hardware, firmware, or be implemented as software or computer code that can be stored in a recording medium (such as a CD ROM, RAM, floppy disk, hard disk, or magneto-optical disk), or be implemented as computer code that is originally stored in a remote recording medium or a non-transitory machine-readable medium and downloaded through a network and will be stored in a local recording medium, so that the method described herein can be stored on such software processes on a recording medium using a general-purpose computer, a dedicated processor, or programmable or dedicated hardware (such as an ASIC or FPGA). It can be understood that a computer, a processor, a microprocessor controller, or programmable hardware includes a storage component (such as a RAM, a ROM, a flash memory, etc.) that can store or receive software or computer code, and when the software or computer code is accessed and executed by the computer, the processor, or the hardware, the method described herein is implemented. In addition, when a general-purpose computer accesses the code for implementing the method shown herein, the execution of the code converts the general-purpose computer into a dedicated computer for executing the method shown herein.

[0076] So far, specific embodiments of the present invention have been described. Other embodiments are within the scope of the appended claims. In some cases, the actions recited in the claims can be performed in a different order and still achieve the desired result. Additionally, the processes depicted in the drawings do not necessarily require the particular order or sequential order shown to achieve the desired result. In certain embodiments, multitasking and parallel processing may be advantageous.

[0077] It should be understood that although this specification is described according to various embodiments, not every embodiment only contains an independent technical solution. This narrative manner of the specification is only for clarity. Those skilled in the art should regard the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

[0078] Finally, it should be noted that the above embodiments are only used to illustrate the embodiments of the present invention, rather than to limit the embodiments of the present invention. Those of ordinary skill in the relevant technical fields can also make various changes and modifications without departing from the spirit and scope of the embodiments of the present invention. Therefore, all equivalent technical solutions also belong to the scope of the embodiments of the present invention, and the patent protection scope of the embodiments of the present invention should be defined by the claims.

Claims

1. A shallow stratum profile data processing method for envelope signals, characterized in that: include: Step S1, performing Hilbert transform processing on the acquired stratigraphic profile data to obtain an analytical signal; Step S2, obtaining an envelope signal by calculating the amplitude of the analytical signal; Step S3, performing a differential operation on the envelope signal to obtain a differential form of the envelope signal; Step S4: Perform a negative value zeroing operation on the differential form of the envelope signal to obtain a final processed signal.

2. The method according to claim 1, characterized in that Each stratigraphic profile data can be expressed as a real-valued sequence: s i (t j ),i=1,2,3,…,n;j=1,2,3,…,m Among them, s i (t j ) represents the real value of the i-th stratigraphic profile data, and each channel has m sampling points.

3. The method according to claim 1, characterized in that The analytical signal can be expressed as: Among them, H[s i (t j )] is s i (t j )’s Hilbert transform.

4. The method according to claim 1, characterized in that: The envelope signal can be expressed as: The differential form of the envelope signal can be expressed as:

5. The method according to claim 1, characterized in that Perform a negative zeroing operation on the differential form of the envelope signal, specifically, zeroing the negative difference: {d i (t j )<0}=0。 6. A shallow stratum profile data processing system for envelope signals, characterized in that: include: The analytical signal module is used to perform Hilbert transform processing on the acquired stratigraphic profile data to obtain an analytical signal; An envelope signal module is used to obtain an envelope signal by calculating the amplitude of the analytical signal; A differential operation module, used for performing a differential operation on the envelope signal to obtain a differential form of the envelope signal; The negative value zeroing operation module is used to perform a negative value zeroing operation on the differential form of the envelope signal to obtain a final processed signal.

7. An electronic device, characterized in that: include: processor; A memory for storing programs; The program includes instructions, which, when executed by the processor, cause the processor to perform the steps of the method as described in any one of claims 1 to 5.

8. A computer storage medium, characterized in that A computer program is stored thereon, and when the program is executed by a processor, the method according to any one of claims 1 to 5 is implemented.

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