使用高分辨率二极光谱图来提取非静止的地震声学信号的特征
Diego Seuret-Jiménez1, Eduardo Trutié-Carrero1, José Manuel Nieto-Jalil2
1Centro de Investigación en Ingeniería y Ciencias Aplicadas, Universidad Autónoma del Estado de Morelos, Campus Chamilpa, Ave. Universidad 1001, Col. Chamilpa, Cuernavaca CP 62209, Mexico.
Sensors (Basel, Switzerland)
|July 14, 2023
概括
研究人员开发了Te-gram,这是一种用于分析频率组件的新工具. 它成功地隔离了12赫兹频段,超越了传统方法,并揭示了对地震信号的新见解.
科学领域:
- 地质物理学 地质物理学
- 信号处理 信号处理
- 波形分析 波形分析
背景情况:
- 传统的时频分析方法很难在没有扭曲的情况下隔离特定的频段.
- 现有的技术在精确分析复杂信号中的能量分布方面存在局限性.
- 识别和分离不同的频率组件对于理解地震事件和背景噪声至关重要.
研究的目的:
- 介绍和评估一个新的数学工具,Te-gram,用于分析地震数据中的频率组件.
- 为了证明Te-gram在隔离特定频段的能力,例如12 Hz频段,这些频段使用传统方法是不可分割的.
- 评估Te-gram在减弱跨期能量和增强频域多重灵敏性的有效性.
主要方法:
- 利用一种新的数学工具,Te-gram,分析能量分布在尺度-频率平面上.
- 采用Daubechies 45波波函数,在排斥频段中以其高衰减 (150dB) 而闻名.
- 使用2017年9月19日墨西哥地震的地震信号数据验证了Te-gram的性能,分析了地震前,期间和后的活动.
主要成果:
- 识别并成功地隔离了大约12 Hz的频段,而不会扭曲其组成频率.
- 与传统方法相比,Te-gram在灵敏度和能量分布分析方面的表现优越.
- 揭示了0.7赫兹和1.75赫兹之间的独特频段,被确定为地球行星噪声,它仍然无法通过其他技术分离.
结论:
- 电图是分析地震数据中复杂频率分布的强大而有效的工具.
- 这种新的方法在隔离特定频段和改进信号分析方面超越了现有的技术.
- 泰格拉姆在多灵敏度和跨期能量减弱方面取得了重大进展,为地震现象和地球自然噪声提供了宝贵的见解.
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