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wigner-ville distribution and its application in seismic attenuation estimation

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Applied Geophysics 2007年第4期4卷 245-254页

作者：李艳东郑晓东中国石油勘探开发研究院物探技术所北京100083

The attenuation of seismic signals is often characterized in the frequency domain using statistical measures of the power spectrum. However, the conventional Fourier transform-based power spectrum estimation methods suffer from time-frequency resolution problems. wigner-ville distribution, which is a member of Cohen class time-frequency distributions, possesses many appealing properties, such as time-frequency marginal distribution, time-frequency localization, etc. Therefore, wigner-ville distribution offers a new way for estimating the attenuation of seismic signals. This paper initially gives a brief introduction to wigner-ville distribution and the smoothed wigner-ville distribution that is effective in reducing the cross-term effect, and then presents a method for seismic attenuation estimation based on the instantaneous energy spectrum of the wigner-ville distribution. A real data example from central Tarim Basin in western China is presented to illustrate the effectiveness of the proposed method. The results show that the wigner-ville distribution-based seismic attenuation estimation method can effectively detect the difference between reef, shoal and lagoon facies by their attenuation properties, indicating that the estimated seismic attenuation can be used for reef and shoal carbonate reservoir characterization.

关键词： wigner-ville distribution time-frequency analysis seismic attenuation reservoir characterization

Nonexistence of cross-term free time-frequency distribution with concentration of wigner-ville distribution

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Science in China(Series F) 2002年第3期45卷 174-180页

作者：邹红星卢旭光戴琼海李衍达 Department of Automation Tsinghua University Beijing 100084 China

wigner-ville distribution (WVD) is recognized as being a powerful tool and a nucleus in time-frequency representation (TFR) which gives an excellent time-frequency concentration, and more importantly, has many desirable properties. A major shortcoming of WVD is the inherent cross-term (CT) interference. Although solutions to this problem from the bulk of contributions to the literature concerning TFR are currently available, none has been able to completely eliminate the CT’s in WVD. It is therefore a common belief that if there exists an auxiliary time-frequency distribution (TFD) which has the same auto-terms (AT’s) as that in WVD, but has CT’s with the opposite sign, then, by adding the auxiliary TFD to WVD, an ideal TFD, which preserves the concentration of WVD while annihilating the CT’s, is readily obtained. However, we prove that the auxiliary TFD does not exist. Moreover, it is found that in general, CT free joint distributions with their concentrations close to that of WVD do not exist either.

关键词： time-frequency analysis wigner-ville distribution cross-term cancellation.

SORTING RADAR SIGNAL BASED ON WAVELET CHARACTERISTICS OF wigner-ville distribution

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Journal of Electronics(China) 2013年第5期30卷 454-462页

作者： Liang Huadong Han Jianghong School of Computer and Information Hefei University of Technology The 38th Institute of China Electronics Technology Group Corporation

Common sorting method have low sorting rates and is sensitive to the Signal-to-Noise Ratio(SNR),wavelet characteristics of wigner-ville distribution are applied to sort unknown complicated radar signal,high sorting accuracy can be *** wigner-ville distribution of received signal is calculated,then it is predigested to two-dimensional *** wavelet transformation to extract characteristics from two-dimensional of wigner-ville distribution,the best characteristics are selected to be used as sorting *** results demonstrated that the characteristics of eight typical radar emitter signals extracted by this method showed good performance of noise-resistance and clustering at large-scale SNR.

关键词： Sorting wigner-ville distribution Wavelet Wavelet packet Normative correlation coefficient

A microscopic ancient river channel identification method based on maximum entropy principle and wigner-ville distribution and its application

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Petroleum Exploration and Development 2021年第6期48卷 1354-1366页

作者： XU Tianji CHENG Bingjie NIU Shuangchen QIN Zhengye WANG Zhenzhen School of Resources and Environment University of Electronic Science and Technology of ChinaChengdu 611731China Yangtze Delta Region Institute of University of Electronic Science and Technology of China Huzhou 313000China State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Chengdu University of TechnologyChengdu 610059China College of Geophysics Chengdu University of TechnologyChengdu 610059China Sichuan Zhongcheng Institute of Coalfield Geophysical Engineering Chengdu 610072China.

In view of the problem of fine characterization of narrow and thin channels,the maximum entropy criterion is used to enhance the focusing characteristics of wigner-ville *** the basis of effectively improving the time-frequency resolution of seismic signal,a new method of microscopic ancient river channel identification is *** on the principle of the equivalence between the maximum entropy power spectrum and the AR model power spectrum,the prediction error and the autoregression coefficient of AR model are obtained using the Burg algorithm and Levinson-Durbin recurrence *** the condition of the first derivative of autocorrelation function being 0,the wigner-ville distribution of seismic signal is calculated,and the wigner-ville distribution time-frequency power spectrum(MEWVD)is obtained under the maxi-mum entropy criterion of the microscopic ancient river *** analysis of emulational seismic signal and forward numerical simulation signal of narrow thin model,it is found that MEWVD can effectively avoid the interference of cross term of wigner-ville distribution,and obtain more accurate spectral characteristics than STFT and CWT signal analysis *** is also proved that the narrow and thin river channels of different scales can be identified effectively by MEWVD of different *** method is applied to the third member of Jurassic Shaximiao Formation(J2s33-2)gas reservoir of the Zhongji-ang gas field in Sichuan *** spatial information of width and direction of narrow and thin river channels with width less than 500 m and sandstone thickness less than 35 m is accurately identified,providing bases for well deployment and horizontal well fracturing section selection.

关键词： maximum entropy principle wigner-ville distribution spectral focusing high resolution seismic fluvial facies narrow and thin ancient channel

Application of spectral decomposition technology in shallow gas detection based on wigner-ville distribution

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Global Geology 2014年第4期17卷 243-246页

作者： CHI Huanzhao LIU Cai SHAN Xuanlong WANG Dian LU Qi College of Earth Sciences Jilin University College of Geo-Exploration Science and Technology Jilin University

Shallow gas is composed of all kinds of shallow buried natural gas resources( < 1500 m) with relatively small reserve for each gas resource. It has some advantages such as shallow burial depth,good physical properties... 详细信息

Shallow gas is composed of all kinds of shallow buried natural gas resources( wigner-Vill distribution,a general spectral decomposition method is applied in the shallow gas detection. Cone-shaped kernel function filtering method is used to suppress cross-terms of the wigner-ville distribution,which is tested on field seismic data. Because of shallow gas reservoir has a characteristic that low frequency energy is stronger and high frequency energy is weaker,it indicates the presence of shallow gas successfully.

关键词： shallow gas wigner-ville distribution cross-term interference kernel function spectral decomposi-tion

Statistical Performance of the wigner-ville distribution and the Cross wigner-ville distribution

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Journal of Shanghai University(English Edition) 2003年第4期7卷 379-383页

作者：陈光化曹家麟 School of Electromechanical Engineering and Automation Shanghai University Shanghai 200072 China

This paper analyzes statistical performances of the wigner-ville distribution (WVD) and the cross wigner-ville distribution (XWVD). Theoretical studies show that XWVD of the analyzed signal can be estimated from XWVD of the noise-contaminated signal . The estimation is unbiased, and the variance is equal to that of noise. In this case, WVD cannot be estimated from WVD of the noise-contaminated signal . Therefore higher SNR is required when using WVD.

关键词： wigner-ville distribution cross wigner-ville distribution instantaneous frequency variance.

Statistical performance of IF estimation of LFM signals with timevarying amplitude using the peak of WVD

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Journal of Systems Engineering and Electronics 2005年第4期16卷 787-791页

作者： Chen Guanghua Ma Shiwei Qin Tinghao Wang Jian Li Ming Cao Jialin Microelectronic Research & Development Center Shanghai Univ. Shanghai 200072 P. R. China

The instantaneous frequency （IF） estimation of the linear frequency modulated （LFM） signals with time-varying amplitude using the peak of the wigner-ville distribution （WVD） is studied. Theoretical analysis shows that the estimation on LFM signals with time-varying amplitude is unbiased, only if WVD of time-varying amplitude reaches its maximum at frequency zero no matter in which time. The statistical performance in the case of additive white Guassian noise is evaluated and an analytical expression for the variance is provided. The simulations using LFM signals with Gaussian envelope testify that IF can be estimated accurately using the peak of WVD for four models of amplitude variation. Furthermore the statistical result of estimation on the signals with amplitude descending before rising is better than that of the signals with constant amplitude when the amplitude variation rate is moderate.

关键词： instantaneous frequency linear frequency modulated signals wigner-ville distribution statistical performance variance.

Joint Time-Frequency Analysis of Seismic Signals:A Critical Review

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Structural Durability & Health Monitoring 2018年第2期12卷 65-83页

作者： Roshan Kumar Wei Zhao Vikash Singh Miami College of Henan University Henan475000China Yokohama University 24000Japan

This paper presents an evaluation of time-frequency methods for the analysis of seismic *** of the present work is to describe,how the frequency content of the signal is changing in *** theoretical basis of short time Fourier transform,Gabor transform,wavelet transform,S-transform,wigner distribution,wigner-ville distribution,Pseudo wigner-ville distribution,Smoothed Pseudo wigner-ville distribution,Choi-William distribution,Born-Jordan distribution and cone shape distribution are *** strengths and weaknesses of each technique are verified by applying them to a particular synthetic seismic signal and recorded real time earthquake data.

关键词： Time-frequency distribution Seismic signals Cross-term interference Autoterm Gabor transform wigner-ville distribution

Research Progress on Discretization of Linear Canonical Transform

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Journal of Beijing Institute of Technology 2021年第3期30卷 205-216页

作者： Yannan Sun Bingzhao Li Ran Tao School of Mathematical Sciences Jiangsu University School of Mathematics and Statistics Beijing Institute of Technology School of Information and Electronics Beijing Institute of Technology

Linear canonical transformation(LCT) is a generalization of the Fourier transform and fractional Fourier transform. The recent research has shown that the LCT is widely used in signal processing and applied mathematics, and the discretization of the LCT becomes vital for the applications of LCT. Based on the development of discretization LCT, a review of important research progress and current situation is presented, which can help researchers to further understand the discretization of LCT and can promote its engineering application. Meanwhile, the connection among different discretization algorithms and the future research are given.

关键词： linear canonical transform(LCT) discrete linear canonical transform sampling wigner-ville distribution fast algorithm