摘要
信号的时频分布具有比时间尺度分布更高的描述和刻画非稳态地震波信号的能力,进一步提高信号的时频聚集性和尽可能减小交叉项干扰是时频分析发展的方向。基于高阶矩时频分布理论,本文首次提出了将其应用于数字化地震波形资料分析和处理的技术途径和方法。通过对仿真信号的Choi-Willams各阶矩时频分布与Wigner各阶矩时频分布的对比和交叉项干扰的理论分析,认为Choi-Willams高阶矩时频分布具有时频聚集性高和交叉干扰项小的特点,在提高处理数字化地震波特性参数精度和地震应急技术系统的智能化程度等方面具有潜在应用前景。
The time-frequency distribution of signal is more suitable for depicting unsteady signal than time-scale distribution. The development tendency of time-frequency analyses is improving the time-frequency conglomeration characteristics of signal and decreasing across disturbance energy item further. Based on the theory of time-frequency analyses on high order moment ,this paper applies time-frequency technology to digital seismic wave data processing first. Compared Choi-Willams time-frequency distribution results of imitation signal with Wigner time-frequency distribution with different order moment, We think that high order moment Choi-Willams time-frequency distribution has higher time-frequency conglomeration characteristics and weaker across disturbance energy item, which has application foreground to improving earthquake source and medium parameters precision and intelligentized degree of earthquake emergency.
引文
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