| 基于连续小波变换的大地电磁信号谱估计方法 |
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| 引用本文： | 徐义贤,王家映.基于连续小波变换的大地电磁信号谱估计方法[J].地球物理学报,2000,43(5):677-683. |
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| 作者姓名： | 徐义贤 王家映 |
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| 作者单位： | 中国地质大学地球物理系,武汉,430074 |
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| 基金项目： | 国家自然科学基金项目!(4 9674 2 2 7) |
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| 摘 要： | 在基于连续小波变换的大地电磁信号谱估计方法中 ,通过引入整体平均、小波系数收缩和显著性检验等统计技术 ,以提高谱估计的精度 .文中同时讨论了连续小波变换中各种参数的选取问题 ,给出了Morlet小波函数中尺度与傅里叶频率之间转换的经验公式 ,并给出了谱估计的具体算法 .结果表明 ,本文方法可有效压制较强的白噪声和局部相关噪声 .与FFT谱估计方法相比 ,该方法大大降低了对信号记录长度的要求 ,因而对大地电磁信号的处理有实际意义 .
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| 关 键 词： | 大地电磁信号 谱估计 连续小波变换 小波系数收缩 显著性检验 |
POWER SPECTRUM ESTIMATION FOR MAGNETOTELLURIC SIGNAL BASED ON CONTINUOUS WAVELET TRANSFORM |
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| XU YI-XIAN,WANG JIA-YING.POWER SPECTRUM ESTIMATION FOR MAGNETOTELLURIC SIGNAL BASED ON CONTINUOUS WAVELET TRANSFORM[J].Chinese Journal of Geophysics,2000,43(5):677-683. |
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| Authors: | XU YI-XIAN WANG JIA-YING |
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| Abstract: | This research aims to improve the accuracy of power spectrum estimation of magnetotelluric signal by using continuous wavelet transform. Three statistic method, global average, wavelet coefficients shrinkaging and significance test, are used to estimate the power spectrum. Empirical formulas are given for the transformation between wavelet scale and Fourier frequency. The algorithm is also described in detail. The numerical tests show that the estimation is robust to stronger white noise and local correlated noise, and significantly decreases the requirement for the recoding length. |
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| Keywords: | Magnetotelluric signal Power spectrum estimation Continuous wavelet transform Wavelet coefficients shrinkaging Significance test |
| 本文献已被 CNKI 万方数据 等数据库收录！ |
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