PROCESSING METHOD AND DEVICE FOR SIMULATING AND ADDING NOISE TO DIGITAL SIGNALS

Abstract

A signal processing method for simulating and adding noise to digital signals, wherein the method is characterized by comprising the following steps: Step 1: Collect the target digital signals or target digital signal traces to be subjected to noise addition processing; Step 2: Generating the white noise signals or white noise signal traces; Step 3: Perform a convolution operation on the target digital signals and the white noise signals to generate color-changing noise signals, or perform a convolution operation on the target digital signal tracks and the white noise signal tracks to generate color-changing noise signal tracks; Step 4: Add the generated color-changing noise signals to the target digital signals, or add the generated color-changing noise signal tracks to the target digital signal tracks.

Description

TECHNICAL AREA

[0001] The invention relates to the technical field of digital signal processing, in particular a processing method and device for simulating and adding noise to digital signals in the field of digital signal processing, such as the field of electronic information, communication (especially wireless communication), biomedical sciences, image enhancement, radar and geophysical signal processing (especially for seismic data processing). BACKGROUND OF THE INVENTION

[0002] In the fields of digital signal processing, as well as geophysical signal processing (especially seismic data processing), electronic information technology, biomedical sciences, radar, communications, image processing, and so on, adding noise to digital signals is generally required for signal simulation processing. For example, during seismic data processing, it is generally necessary to suppress noise to improve the signal-to-noise ratio. Regular noise, such as multiple wave, scattered waves, and surface waves, must typically be eliminated or suppressed by applying a multidimensional filtering technique.However, multidimensional filtering methods can cause an aliasing effect, and one of the consequences of this effect is that the output time section becomes too inflexible. Therefore, it is highly relevant to perform simulations and noise-adding processing on the trace gathers obtained after multidimensional filtering.

[0003] The existing digital signal noise addition methods can be divided into two types, one being the addition of white noise to digital signals, and the other being the addition of colored noise to digital signals.

[0004] White noise refers to random noise signals whose power density is constant across an unlimited frequency range, and whose characteristics are uncorrelated with each other, thus representing, to some extent, the stochastic behavior of signals. Colored noise refers to random noise signals whose power density varies with the signal frequencies, and it can be identified according to its sensitivity to, or within, different frequency ranges. Well-known colored noise includes pink noise, red noise, orange noise, blue noise, violet / purple noise, gray noise, brown noise, and black noise (statistical noise). Currently, studies of noise in the field of digital signal processing are still at the stage of noise identification, while studies of synthesizing new noise are almost nonexistent.

[0005] As previously described, noise addition processing in the prior art typically involves adding white noise or colored noise to the target signals or signal traces. Specifically, in the prior art, Si'(t) the noise-added signal trace, which is obtained by directly adding white noise signal traces to the target signal traces, which is one of the usual noise-added methods ( Fig. 3 and Fig. Figure 8 shows the time interval or spectrum of the noise-added signal trace gather. It has a general expression of Si'(t)=Si(t)+μN1(t), where S i (t) is the target signal trace which is to be subjected to noise addition and simulation processing ( Fig. 1 and Fig. Figure 6 shows the time section or spectrum of the target signal trace gather. i (t) is the white noise signal track or the white noise signal track collection ( Fig. 2 and Fig. Figure 7 shows the time section (or spectrum of the white noise signal track collection), µ represents the proportionality coefficient, t represents the time, and i represents the sequence number of the signal track.

[0006] It can be made of Fig. 3 and Fig. It can be seen that the noise-adding method, or the noise-adding method of directly adding white noise to the target signal or signal traces, cannot reflect or restore the original waveform system, thus exhibiting a low degree of simulation. Similarly, the noise-adding method of directly adding colored noise to the target signal cannot reflect or restore the original waveform system, thus exhibiting a low degree of simulation.

[0007] From EP 1 164 696 B1, a signal processing method for simulating and adding noise to digital signals is known, comprising the following steps: collecting the target digital signals, generating the white noise signals, and performing a convolution operation on the target digital signals and the white noise signals to generate color-changing noise signals. A similar method is also known from DE 198 14 971 A1.

[0008] From US 2008 / 0 195 358 A1 a signal processing method for simulating and adding noisy reflections to digital signals is known, comprising the steps: collecting the target digital signals, generating the noisy reflections and performing a convolution operation on the target digital signals and the noisy reflections. SUMMARY OF THE INVENTION

[0009] The problem underlying the present invention is solved according to the invention as specified in the main claims. Exemplary embodiments of the invention are set forth in the dependent claims.

[0010] To solve one or more of the aforementioned problems present in the prior art, the invention provides a novel noise-generating method for performing simulation and noise-adding processing in the field of digital signal processing, thereby generating a novel synthetic noise. This novel synthetic noise is a natural and realistic random noise, and the signal or signal trace subjected to noise augmentation by the novel noise exhibits an extremely high simulation degree.

[0011] The color-changing noise signals and signal traces are digital signals or signal traces obtained by performing a convolution operation on the target digital signals or signal traces and the white noise signals or signal traces.

[0012] Preferably, the color-changing noise signal is represented by N^(t), which is considered Ni(t)=N(t)*Si(t) is expressed where N(t) represents the white noise signal, S(t) represents the target signal to be subjected to the noise addition operation, t represents time, and the operator “*” represents the convolution operation.

[0013] The preferred color-changing noise signal trace is represented by Ni(t) which is expressed as Ni(t)=Ni(t)*Si(t) where N i (t) represents the white noise signal trace, S i(t) represents the target signal track to be subjected to the noise-adding operation, i represents the sequence number of the signal tracks, t represents the time, and the operator “*” represents the convolution operation.

[0014] The invention can be broadly applied to the technical field of digital signal processing, as well as the fields of electronic information, communication (especially wireless communication), biomedical sciences, image enhancement, radar, and geophysical signal processing (especially seismic processing) to perform ideal noise-adding processing. For example, if the invention were applied to the seismic signal processing, the target digital traces would be the signal traces obtained after multidimensional filtering of the seismic digital signals. Using the invention, ideal simulation and noise-adding processing can be performed on the multidimensionally filtered digital seismic signals.

[0015] When comparing the spectrum output of the signals or signal traces with the added color-changing noise with the spectrum output of the signals or signal traces with added white noise or colored noise, it can be seen that the signals, signal traces or signal trace gathers, which have been subjected to an addition using the color-changing noise of the invention, exhibit an extremely high simulation degree, whereby the color-changing noise of the invention is a natural, realistic and synthetic random noise. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] To describe the exemplary embodiments of the present invention in detail, reference is now made to the attached figures, so that the aspects, features, and advantages of the present invention can be understood more precisely. The figures show: Fig. 1 a graph representing the time section of the target signal trace gather to be subjected to noise addition and simulation processing; Fig. 2 a graph representing the time interval of the white noise signal trace gather; Fig. 3 a graph representing the time interval of the signal track collection with added noise or the noise-added signal track collection obtained by directly adding or adding white noise signal tracks to the target signal tracks in accordance with the prior art; Fig. 4 a graph which represents the time interval of the signal trace collection of the new random noise (e.g. color-changing noise) which is generated according to the present invention; Fig. Figure 5 is a graph showing the time interval of the noise-added signal track collection obtained by adding the color-changing noise signal track generated according to the invention to the target signal tracks; Fig. Figure 6 is a graph showing the spectrum of the target signal track collection to be subjected to noise-adding processing; Fig. Figure 7 is a graph representing the spectrum of the white noise signal trace collection; Fig. Figure 8 is a diagram showing the spectrum of the noise-added signal track collection obtained by directly adding the white noise signal tracks to the target signal tracks according to the state of the art; Fig. Figure 9 is a graph representing the spectrum of the color-changing noise signal track collection generated according to the invention; Fig. Figure 10 is a graph representing the spectrum of the noise-added signal track collection obtained by adding the color-changing noise tracks generated in accordance with the invention to the target signal tracks; Fig. Figure 11 is a graph showing the velocity spectrum (see left part of the graph) and the time interval (see right part of the graph) of a group of original CMP traces or CMP gathers (i.e., common center traces or common center gathers) collected at a seismic exploration work area, in accordance with a preferred embodiment of the invention; Fig. Figure 12 is a graph showing the spectrum of the original CMP traces or collections, as in Fig. 11 shown, represents; Fig. Figure 13 is a graph that represents the velocity spectrum (see left part of the graph) and the time interval (see right part of the graph) of the CMP tracks or the CMP collection, which are obtained by eliminating the multi-wave interference on the original CMP collection, as in Fig. 11 and Fig. 12 shown, will be received; Fig. Figure 14 is a graph showing the spectrum of the CMP collection, which has been denoised by the final noise of the CMP collection, whereby the multi-wave difference has been eliminated, as in Fig. 13 shown, represents; Fig. Figure 15 is a graph showing the velocity spectrum (see left part of the graph) and the time interval (see right part of the graph) of the CMP collection obtained by adding white noise to the signal gathers, as in Fig. 13 shown, is obtained; Fig. Figure 16 is a graph representing the spectrum of the CMP collection obtained by adding white noise to the signal trace collection, as in Fig. 13 shown, is obtained; Fig. Figure 17 is a graph representing the bandpass-filtered CMP collection, which is processed by bandpass filters of the CMP collection that has added white noise, as in Fig. 15 and Fig. 16 shown, is obtained; Fig. Figure 18 is a graph representing the velocity spectrum (see left part of the graph) and the time interval (see right part of the graph) of the CMP collection, which is obtained by adding 30% of the original noise (i.e., colored noise) to the signal trace collection, as in Fig. 13 shown, which is obtained according to the state of the art; Fig. Figure 19 is a graph showing the velocity spectrum (see left part of the graph) and the time interval (see right part of the graph) of the CMP collection obtained by adding 30% of color-banding noise to the signal track collection (i.e., the target signal track collection) that was in Fig. 13 is shown, according to which the invention is obtained; Fig. Figure 20 is a graph showing the spectrum of the CMP collection with color-banding noise added to it, as in Fig. 19 shown, represents; Fig. Figure 21 is a flowchart that illustrates the implementation in a time domain of the simulation and noise addition operation according to the invention; Fig. Figure 22 is a flowchart which represents implementation in a frequency domain of the simulation and noise addition processing according to the invention; Fig. Figure 23 shows the simulation and noise addition device according to a preferred embodiment of the invention.

[0017] It is noted that in all figures representing the time interval, the horizontal axis represents the sequence number of the signal track, and the vertical axis represents the time (t); in all spectra, the horizontal axis represents the frequency (f) and the vertical axis represents the amplitude (|A|); and in all velocity spectra, the horizontal axis shows the velocity (v) and the vertical axis represents (t). DETAILED DESCRIPTION OF THE INVENTION

[0018] Several terms are used throughout the application document to designate specific system components. As a person skilled in the art understands, different names can commonly be used to refer to the same component; therefore, this application document does not intend to distinguish between components that are named differently but have the same function. In this application document, the terms "comprise," "include," and "have" are used in an open manner, meaning they should be interpreted as "comprehensive but not limited to..." Additionally, the term "couple" or "couples" signifies an indirect or direct electrical connection. Therefore, if a first device is coupled to a second device, the connection may be made by a direct electrical connection or by an indirect electrical connection via other devices or connections.

[0019] The invention is described below with reference to the figures.

[0020] As previously described, the methods for adding noise to digital signals can be divided into two types: one for adding white noise to digital signals and the other for adding colored noise. However, neither of these two types of noise addition methods can truly reflect or reconstruct the original waveform system, thus exhibiting a low degree of simulation, as illustrated in Fig. 3, Fig. 6, Fig. 7 and Fig. 8 shown.

[0021] Fig. Figure 6 shows the spectrum of the target signal trace gather. i (t), which is to be subjected to noise-adding processing, Fig. Figure 7 shows the spectrum of the white noise signal trace gather. i(t), Fig. Figure 3 shows the time section of the noise-added signal track collection. Si'(t), which is achieved by directly adding white noise signal tracks to the target signal tracks, according to the state of the art, and Fig. Figure 8 shows the spectrum of the noise-added signal trace gather. Si'(t), which is obtained by directly adding the white noise signal traces to the target signal traces.

[0022] As in Fig. As shown in section 3, during the time period of the noise-added signal track collection, it is possible Si'(t), The signal obtained by directly adding white noise signal traces to the target signal traces obviously shows signs of noise-added processing. Additionally, the spectrum of the noise-added signal trace collection can be used to determine... Si'(t), which is obtained by adding the white noise signal traces, as in Fig. As shown in Figure 8, the added white noise is evenly distributed across the entire frequency range. Therefore, the conventional noise-adding process of directly adding the white noise has a low simulation level.

[0023] To eliminate the disadvantages of the prior art, the invention provides a method for synthesizing a new noise (hereinafter referred to as color-changing noise), as well as a method and a device for performing noise-adding processing using the new noise.

[0024] A method for synthesizing color-changing noise includes the following steps: Step 1: Collecting target digital signals or target digital signal traces to be subjected to noise addition processing; Step 2: Generating white noise signals or white noise signal traces; Step 3: Perform a convolution operation on the target digital signals and the white noise signals to generate color-changing noise signals, or perform a convolution operation on the target digital signal tracks and the white noise signal tracks to generate color-changing noise signal tracks; and Step 4: Outputting the generated color-changing noise signals or color-changing noise signal tracks.

[0025] Preferably, the method for synthesizing color-changing noise can be implemented in the time domain, which includes the following steps when implemented in the time domain: Collection of destination digital signals S(t) or destination digital signal tracks S i (t), which are to be subjected to noise addition processing, where t represents the time and i represents the sequence number or sequence number of signal traces;

[0026] Generating white noise signals N(t) or white noise signal tracks N i (t); Performing a convolution operation on the target digital signals S(t) and the white noise signals N(t) to generate color-changing noise signals N^(t), or performing a convolution operation on the target digital signal tracks S i (t) and the white noise signal tracks N i (t) to color-changing noise signal traces Ni(t) to produce; and

[0027] Output of the generated color-changing noise signals N^(t) or color-changing noise signal traces Ni(t).

[0028] Furthermore, the method for synthesizing color-banding noise in a frequency domain can preferably be implemented, which includes the following steps when implemented in the frequency domain: Collection of destination digital signals S(t) or destination digital signal tracks S i (t), which are to be subjected to noise-adding processing; Generating white noise signals N(t) or white noise signal tracks N i (t); Performing a Fourier transform on the target digital signals S(t) or the target digital signal tracks S i (t) to target digital frequency-domain signals S(ω) or target digital frequency-domain tracks S i(ω) to obtain or obtain, where ω represents the frequency and i represents the sequence number or sequence number of signal tracks; performing Fourier transformation on the white noise signals N(t) or the white noise signal tracks N i (t), to white noise frequency-domain signals N(ω) or white noise frequency-domain signal traces (Engl.: white noise frequency-domain signal traces) N i (ω) to obtain; performing a multiplication operation on the target digital frequency-domain signals (S) i (ω) and the white noise frequency-domain signals N(w) to generate color-changing noise frequency-domain signals N^(ω), or by performing a multiplication operation on the target digital frequency-domain signal tracks S i (ω) or the white noise frequency range signal traces N i(ω), to color-changing noise frequency-domain signal traces (Engl.: color-changing noise frequency-domain signal traces) Ni(ω) to produce; Performing an inverse Fourier transform on the color-banding noise frequency range signals N^(ω) or the color-banding noise frequency range signal traces Ni(ω), around the color-changing noise signals N^(t) or the color-changing noise signal traces Ni(t) to obtain; and Output of the generated color-changing noise signals N^(t) or color-changing noise signal traces Ni(t).

[0029] Obviously Ni(t), that is generated in the description, not entirely of the colored noise type, if S i (t) is a white noise signal track, is Ni(t) also a white noise signal trace. Ni(t) is a new type of random noise, which is similar to the type of S i (t) varies between the white noise signal and the colored noise signal, which is thus called color-changing noise in the invention.

[0030] As in Fig. 4 and Fig. Shown in 9 is the color-changing noise. Ni(t), that shown in the invention, still random noise, and the energy distribution characteristics (see Fig. 4) of Ni(t) during this time period, the energy distribution characteristics of the target digital signal tracks S are consistent. i (t) agree, and the spectral properties (see Fig. 9) of Ni(t) They also agree with the spectral properties of the S i (t) agree.

[0031] Therefore, the result of the analysis shows that the color-changing noise generated in the invention is a relatively natural and realistic synthetic random noise.

[0032] A preferred embodiment of the invention will now be described.

[0033] According to this embodiment, the invention provides a processing method for simulating and adding noise to digital signals, which comprises the following steps: Step 1: Collect the target digital signals or target digital signal traces to be subjected to noise addition processing; Step 2: Generating the white noise signals or white noise signal traces; Step 3: Perform a convolution operation on the target digital signals and the white noise signals to generate color-changing noise signals, or perform a convolution operation on the target digital signal tracks and the white noise signal tracks to generate color-changing noise signal tracks; Step 4: Adding the generated color-changing noise signals to the target digital signals; Step 5: Outputting the digital signals or digital signal tracks that have undergone noise-adding processing.

[0034] Preferably, as in Fig. Figure 21 shows that the processing method for simulating and adding noise to digital signals can be implemented in a time domain, and the method for simulating and adding noise comprises the following steps when implemented in a time domain: (1) Collecting destination digital signals S(t) or destination digital signal tracks S i (t), which are to be subjected to noise addition processing, where t represents time and i represents the sequence number or sequence number of signal tracks; (2) Generating white noise signals N(t) or white noise signal tracks N i (t); (3) Performing a convolution operation on the target digital signals S(t) and the white noise signals N(t) (i.e., N^(t) = N(t)*S(t)) to generate color-banding noise signals N^(t), or performing a convolution operation on the target digital signal tracks S i (t) and the white noise signal tracks Ni (t), (i.e. Ni(t)=N(t)*Si(t)), color-changing noise signal traces Ni(t) to generate; and (4) adding the generated color-changing noise signals N^(t) to the target digital signals S(t), or adding the generated color-changing noise signal tracks. Ni(t) to the target digital signal tracks S i (t); and (5) Output of the noise-added digital signals S^(t) or digital signal tracks Si'(t).

[0035] Preferably, the processing of adding or adding color-changing noise signals, as described in step (4) above, is carried out according to the equation S^(t) = S(t) + µN^(t), where µ represents the proportionality coefficient, which can be determined by technicians according to practical requirements.

[0036] Preferred is the processing of the addition or augmentation of color-changing noise signal traces, as described in step (4) above, according to the equation Si'(t)=Si(t)+μNi(t), performed, where i represents the sequence number of the signal track, which is a positive integer; µ represents the proportionality coefficient, which is preferably a percentage between 0 and 1.

[0037] Preferably, as in Fig. Figure 22 shows that the processing method for simulating and adding noise to digital signals is implemented in the frequency domain, and the method for simulating and adding or adding noise comprises the following steps when implemented in the frequency domain: (1) Collecting destination digital signals S(t) or destination digital signal tracks S i (t), which are to be subjected to noise-adding processing; (2) Generating white noise signals N(t) or white noise signal tracks N i (t); (3) Performing a Fourier transform on the target digital signals S(t) or the target digital signal tracks S i (t) to obtain target digital frequency domain signals S(ω) (i.e., S(w) = FFT {S(t)}) or target digital frequency domain signal traces S i (ω) to attain (i.e. S i (ω) = FFT {S i (t)}); (4) Performing a Fourier transform on the white noise signals N(t) or the white noise signal tracks N i (t) to white noise frequency range signals N(ω) (i.e. N i (ω) = FFT {N i (t)}) or white noise frequency range signal traces N i (ω) (i.e. N i (ω) = FFT {Ni(t)}); (5) Performing a multiplication operation on the target digital frequency range signals S(ω) and the white noise frequency range signals N(w) to obtain color-banding noise frequency range signals N^(ω) (i.e., N^(ω) = N(ω) · S(ω))) or performing a multiplication operation on the target digital frequency range signal tracks S i (ω) and the white noise frequency range signal traces N i (ω), to color-changing noise frequency range signal traces Ni(ω) to obtain (i.e. Ni(ω)=Si(ω)); (6) Performing an inverse Fourier transform on the color-banding noise frequency range signals N^(ω) or the color-banding noise frequency range signal tracks Ni(ω), to calculate the color-changing noise signals N^(t) (i.e., N^(t) = FFT) -1 {N^(ω)}) or the color-changing noise signal traces Ni(t) (i.e. Ni∧(t)=FFT−1{Ni∧(ω)} to obtain; (7) Output of the generated color-changing noise signals N^(t) or color-changing noise signal traces N^(t); (8) Adding the generated color-changing noise signals N^(t) to the destination digital signals, or adding the generated color-changing noise signal tracks N^(t) to the destination digital signal tracks S i (t); and (9) Output of the noise-added digital signals S^(t) or digital signal tracks Si∧(t) (this step is not in Fig. 22 shown.

[0038] Preferably, the processing of adding or adding color-changing noise signals, as described in step (8) above, is carried out according to the equation S^(t) = S(t) + µN^(t), where i represents the proportionality coefficient, which can be determined by technicians according to practical needs.

[0039] The preferred method is to add color-changing noise signal traces, as described in step (8) above, according to the equation Si∧(t)=Si(t)+μNi∧(t) performed, where i represents the sequence number or sequence number of the signal tracks and µ represents the proportionality coefficient.

[0040] By comparing Fig. 5 (i.e., the time period of the noise-added signal track collection according to the invention) with Fig. 3 (i.e., the time period of noise-added signal trace gather according to the state of the art) and comparisons of Fig. 10 (i.e., the spectrum of the noise-added signal track collection according to the invention) with Fig. 8 (i.e., the spectrum of the noise-added signal track collection according to the state of the art) it can be clearly seen that both in the time period ( Fig. 5) as well as in the spectrum ( Fig. 10) the digital signal track Si∧(t), The noise generated according to the invention, which is obtained by performing noise-adding processing using the color-changing noise, shows almost no sign of the noise-adding processing. This can demonstrate that the color-changing noise generated according to the invention is a natural and realistic synthetic random noise, and that the target signals or signal traces subjected to noise-adding with the color-changing noise exhibit a very high degree of simulation compared to prior art noise-adding methods.

[0041] Next, an embodiment of the invention will be described in detail with reference to Fig. 23 described.

[0042] Fig. Figure 23 shows an embodiment of the present invention, which relates to a simulating and noise-adding device 100 for simulating and adding noise to digital signals, the device comprising: An input means 101 for inputting the target digital signals or target digital signal tracks to be subjected to noise-adding processing; a white noise generating device for generating white noise signals or white noise signal traces; a color-changing noise generator 103, which is coupled to the input device 101 and the white noise generator 102 and is configured to perform a convolution operation on the target digital signals and the white noise signals to generate color-changing noise signals or to perform a convolution operation on the target digital signal tracks and the white noise signal tracks to generate color-changing noise signal tracks. A noise addition processing means 104, which is coupled to the input means 101 and the color-changing noise generation means 103, and is configured to add the generated color-changing noise signals to the destination digital signals or to add the generated color-changing noise signal tracks to the destination digital signal tracks; an output device 105 for outputting the noise-added digital signals or digital signal tracks.

[0043] Preferably, the color-changing noise generating means 103 is further configured to perform a convolution operation on the target digital signals S(t) and the white noise signals N(t) (i.e., N^(t) = N(t)*S(t)) to generate the color-changing noise signals N^(t), or to perform a convolution operation on the target digital signal tracks S i (t) and the white noise signal tracks N i (t) to perform (i.e. Ni∧(t)=Ni(t)∗Si(t)), around the color-changing noise signal traces (English: color-changing noise signal traces) Ni∧(t) to produce.

[0044] Alternatively, the color-changing noise-generating device 103 is further configured to: Performing a Fourier transform on the target digital signals S(t), or the target digital signal tracks S i(t) to target digital frequency range signals S(ω) (i.e., S(w) = FFT{S(t)}) or target digital frequency range signal traces S i (ω) (i.e. S i (ω) = FFT{S i (t)}) to obtain; Performing a Fourier transform on the white noise signals N(t) or the white noise signal tracks N i (t) to white noise frequency domain signals N(ω) (i.e., N(ω) = FFT {N(t)}) or white noise frequency domain signal traces N i (ω) (i.e. N i (ω) = FFT{N i (t)}) to obtain; Performing a multiplication operation on the target digital frequency-domain signals S(ω) and the white noise frequency-domain signals N(w) to generate color-banding noise frequency-domain signals N'(w) (i.e., N^(ω) = N(ω) · S(ω)), or performing a multiplication operation on the target digital frequency-domain signal tracks S i (ω) or the white noise frequency range signal traces N i(ω), to color-changing noise frequency range signal traces Ni∧(ω) (i.e. Ni∧(ω)=Ni(ω)⋅Si(ω))) to produce; Performing an inverse Fourier transform on the color-banding noise frequency range signals N^(ω) or the color-banding noise frequency range signal tracks Ni∧(ω), to calculate the color-changing noise signals N^(t) (i.e., N^(t) = FFT) -1 {N^(ω)}) or the color-changing noise signal traces Ni∧(t) (i.e. Ni∧(t)=FFT−1{Ni∧(ω)} to obtain or to produce (English: obtain).

[0045] Preferably, the noise-adding processing means 104 is further configured to perform the noise addition according to the equation S^(t) = S(t) + µN^(t), where S(t) represents the target digital signal to be subjected to noise-adding processing, N^(t) represents the color-changing noise signal, ω represents the proportionality coefficient, and e^N^(t) represents the noise-adding digital signal.

[0046] Preferably, the noise-adding processing means 104 is further configured to perform the noise addition according to the equation Si∧(t)=Si(t)+μNi∧(t) to perform, whereby S i (t) represents the destination digital signal track, Ni∧(t) The color-changing noise signal track is represented, S^(t) represents the noise-added digital signal track, i represents the sequence number of the signal tracks, µ represents the proportionality coefficient, and t represents time.

[0047] The characteristics and advantages of the present invention are further described with reference to the following specific examples.

[0048] Fig. Figure 11 shows the velocity spectrum (see left part of the graph) and the time section (see right part of the graph) of a group of original CMP collections or CMP gathers (i.e., common midpoint gathers) collected at a seismic exploration work area, according to a preferred embodiment of the invention. Fig. Figure 12 shows the spectrum of the original CMP collections as in Fig. Figure 11 shows that serious multi-wave interference can occur below 3500 ms.

[0049] Fig. Figure 13 shows the velocity spectrum (see left part of the graph) and the time interval (see right part of the graph) of the CMP collections obtained by eliminating multi-wave interference on the original CMP collections, as in Fig. 11 and Fig. 12 shown, can be obtained. Fig. Figure 14 shows the spectrum of the CMP collection or CMP track or CMP gathers, which is eliminated by the final noise of the CMP collection with the multi-wave interference, as shown in Fig. 13 shown, was obtained. It can be derived from the velocity spectrum that is in Fig. Figure 13 shows that the multi-wave interference has been eliminated, however, there is still a problem that the CMP collection looks like a synthetic model and is unnatural.

[0050] Fig. Figure 19 shows the velocity spectrum (see left part of the graph) and the time interval (see right side of the graph) of the CMP collection obtained by adding white noise to the signal trace collection, as in Fig. 13 shown, is obtained. Fig. Figure 16 shows the spectrum of the CMP collection, which is obtained by adding white noise to the signal track collection, as in Fig. 13 was shown, was obtained. Fig. Figure 17 shows the spectrum of the bandpass-filtered CMP collection, which, when combined with bandpass filters of the CMP collection, exhibits white Gaussian noise added to it, as in Fig. 15 and Fig. 16 shown, is obtained. It can be seen from these three figures that there is an obvious sign of the addition of white noise both in the time period ( Fig. 15) or the spectrum ( Fig. 16). Although the bandpass filtering (5, 10, 60, 80 Hz) can hide the noise-added characteristics in the time interval, the output spectrum ( Fig. 17) still shows signs of adding white noise, and is not desired in the data analysis process.

[0051] Fig. Figure 18 shows the velocity spectrum (see left part of the graph) and the time interval (see right part of the graph) of the CMP collection obtained by adding 30% of the original noise (i.e., colored noise) to the signal trace collection that was in Fig. As shown in section 13, this is achieved according to the state of the art. It can be derived from Fig. 18. It can be seen that the multi-wave interference in the CMP collection can be partially attenuated, however, there is still a large multi-wave energy in the velocity spectrum, which is very disadvantageous.

[0052] Fig. Figure 19 shows the velocity spectrum (see left part of the graph) and the time interval (see right part of the graph) of the CMP collection obtained by adding 30% of the color-banding noise to the signal track collections (i.e., the target signal track collections) that are in Fig. 13 are shown, which is obtained according to the invention. Fig. Figure 20 shows the spectrum of the CMP collections with color-banding noise added to this, as in Fig. Figure 19 shows that the time interval of the CMP collections appears natural and that there are no multi-waves in the velocity spectrum. Furthermore, by comparing the spectra of the CMP collections shown in Fig. As shown in Figure 19, the spectra of the target signal track collections demonstrate that adding the color-changing noise to the target signal track collections does not alter their spectral properties. Therefore, there is almost no trace of the noise-added processing in either the time period or the spectrum, and consequently, the result is ideal.

[0053] From the illustrations above, it can be seen that the output signal trace gathers, generated by performing noise-added processing with color-banding noise according to the invention, are characterized by the presence of obvious noise in the time domain, but no obvious noise in the frequency domain. In other words, no signs of noise-added processing are visible in either the time domain or the spectrum of the noise-added signal traces according to the invention, and the noise-added signal traces exhibit an extremely high degree of simulation, which is very helpful in solving noise reduction, simulation, and noise-added problems in digital signal processing.

[0054] The above descriptions of the embodiments are in no way more than illustrative, nor are they to be considered limiting. The scope of protection of the present invention is defined by the claims.

Claims

[1] Signal processing method for simulating and adding noise to digital signals, wherein the method characterized by The fact is that it includes the following steps: Step 1: Collect the target digital signals or target digital signal traces to be subjected to noise addition processing; Step 2: Generating the white noise signals or white noise signal traces; Step 3: Perform a convolution operation on the target digital signals and the white noise signals to generate color-changing noise signals, or perform a convolution operation on the target digital signal tracks and the white noise signal tracks to generate color-changing noise signal tracks; Step 4: Add the generated color-changing noise signals to the target digital signals, or add the generated color-changing noise signal tracks to the target digital signal tracks. [2] Method according to claim 1, characterized by , that step 3 further shows: Performing a convolution operation on the target digital signals S(t) and the white noise signals N(t) to generate color-changing noise signals N^(t), or performing a convolution operation on the target digital signal tracks S i (t) or the white noise signal tracks N i (t) to color-changing noise signal traces Ni∧(t), to generate, where t represents time and i represents the sequence number of signal traces. [3] Method according to claim 1, characterized by , that step 3 further includes: Performing a Fourier transform on the target digital signals S(t) or the target digital signal tracks S i (t) to target digital frequency range signals S(ω) or target digital frequency range signal traces S i (ω) to obtain; Performing a Fourier transform on the white noise signals N(t) or the white noise signal tracks N i (t) to white noise frequency range signals N(w) or white noise frequency range signal traces N i (ω) to obtain; where t represents time, i represents the sequence number of signal traces, and ω represents the frequency. [4] Method according to claim 3, characterized by , that step 3 further includes: Performing a multiplication operation on the target digital frequency domain signals S(ω) and the white noise frequency domain signals N(w) to generate color-banding noise frequency domain signals N^(ω), or performing a multiplication operation on the target digital frequency domain signal tracks S i (ω) and the white noise frequency range signal traces N i (ω), to color-changing noise frequency range signal traces Ni(ω) to produce; Performing an inverse Fourier transform on the color-banding noise frequency domain signals N^(ω) or the color-banding noise frequency domain signal traces Ni(ω), around the color-changing noise signals N^(t) or the color-changing noise signal traces Ni(t) to obtain; where t represents time, i represents the sequence number of signal traces, and ω represents the frequency. [5] Method according to claim 2, characterized by , that the processing of adding color-changing noise signals, as described in step 4, is performed according to the following equation: S(t)=S(t)+μN(t) where µ represents the proportionality coefficient and t represents time. [6] Method according to claim 2, characterized by, that the processing of adding color band dens noise signals, as described in step 4, is performed according to the following equation: Si(t)=Si(t)+μNi(t) where represents the sequence number of signal traces, µ represents the proportional coefficient, and t represents time. [7] Method according to claim 1, characterized by that the target digital signal traces are the signal traces of multidimensionally filtered seismic data. [8] Device for simulating and adding noise to digital signals, characterized by , that the facility includes: an input means (101) for inputting the destination digital signals or destination digital signal tracks to be subjected to noise-adding processing; a white noise generating device (102) for generating white noise signals or white noise signal traces; a color-changing noise generator (103) coupled to the input device (101) and the white noise generator (102), and configured to perform a convolution operation on the destination digital signals and the white noise signals to generate color-changing noise signals, or to perform a convolution operation on the destination digital signal tracks and the white noise signal tracks to generate color-changing noise signal tracks; and a noise addition processing means (104) coupled to the input means (101) and the color-changing noise generation means (103) is configured to add the generated color-changing noise signals to the destination digital signals, or to add the generated color-changing noise signal tracks to the destination digital signal tracks. [9] Device according to claim 8, characterized by, that the color-changing noise generator (103) is further configured to perform a convolution operation on the target digital signals S(t) or the white noise signals N(t) to generate the color-changing noise signals N^(t), or to perform a convolution operation on the target digital signal tracks S i (t) and the white noise signal tracks N i (t) to perform the color-changing noise signal traces Ni(t) to generate, where t represents time and i represents the sequence number of signal traces. [10] Device according to claim 8, characterized by , that the color-changing noise-generating device (103) is further configured to: Performing a Fourier transform on the target digital signals S(t) or the target digital signal tracks S i (t) to target digital frequency range signals S(ω) or target digital frequency range signal traces S i (ω) to obtain; and Performing a Fourier transform on the white noise signals N(t) or the white noise signal tracks N i (t) to white noise frequency domain signals N(ω) or white noise frequency domain signal traces N i (ω) to obtain; where t represents time, i represents the sequence number of signal traces, and ω represents the frequency. [11] Device according to claim 10, characterized by , that the color-changing noise-generating device (103) is further configured to: Performing a multiplication operation on the target digital frequency range signals S(ω) and the white noise frequency range signals N(w) to generate color-banding noise frequency range signals N^(ω), or performing a multiplication operation on the target digital frequency range signal tracks S i (ω) and the white noise frequency range signal traces N i (ω), to color-changing noise frequency range signal traces Ni(ω) to produce; and Performing an inverse Fourier transform on the color-banding noise frequency domain signals N^(ω) or the color-banding noise frequency domain signal traces Ni(ω), around the color-changing noise signals N^(t) or the color-changing noise signal traces Ni(t) to obtain where t represents time, i represents the sequence number of signal traces, and ω represents the frequency t. [12] Device according to claim 9, characterized by , that the noise addition processing means (104) is further configured to perform noise addition processing according to the following equation: S^(t) = S(t) + µN^(t) where S(t) is the target digital signal to be subjected to noise-adding processing, N^(t) is the color-changing noise signal, S^(t) is the noise-adding digital signal, µ represents the proportional coefficient, and t represents time. [13] Device according to claim 9, characterized by , that the noise-adding processing means (104) is further configured to perform noise-adding processing according to the following equation: Si(t)=Si(t)+μNi(t), where S i (t) is the target digital signal track, N^(t) is the color-changing noise signal track, Si(t) where is the noise-added digital signal track, i represents the sequence number of the signal track, µ represents the proportional coefficient, and t represents the time. [14] Device according to claim 8, characterized bythat the target digital signal traces are the signal traces of multi-dimensional filtered seismic data. [15] Device according to claim 8, characterized by , that the device is used to simulate and add noise to the multi-dimensional filtered digital seismic signals during processing of the seismic waves.

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