基于广义S变换的槽波高精度滤波与多频速度成像研究

Research on channel wave high-precision filtering and multi-frequency velocity imaging based on generalized S transform

频散曲线提取和信号去噪是槽波数据处理的重要步骤.广义S变换综合了短时傅里叶与小波变换的优点,能够提取稳定清晰、分辨率高的频散曲线,同时存在逆变换能够对信号进行高精度滤波.本文提出了广义S变换在槽波数据处理中的两种关键作用,一种利用广义S变换对槽波数据进行精准滤波去噪提高槽波信噪比,用于提高槽波振幅衰减系数成像质量,一种利用广义S变换自动快速拾取多个槽波频率的速度,得到多个速度成像结果,用于优化槽波速度成像效果.将广义S变换滤波应用于车集煤矿某工作面,振幅衰减系数成像结果比常规处理更加准确和清晰;将广义S变换多频速度成像应用于龙王庄煤矿煤厚反演,通过与实际的揭露对比,证明广义S变换在煤厚反演方面具有比较高的准确性.

Dispersion curve extraction and signal denoising are important steps in channel wave data processing.The generalized S transform combines the advantages of short-time Fourier transform and wavelet transform,which can extract more stable and clear dispersion curves with higher resolution.At the same time,the generalized S transform has an inverse transform to high-precision signal filtering.In this paper,two key roles of generalized S transform in channel wave data processing are proposed.One is to improve the signal-to-noise ratio of channel wave by using generalized S transform to accurately filter and denoise the channel wave data,which is used to improve the imaging quality of amplitude attenuation coefficient of channel wave.The other is to automatically and quickly pick up the velocity of multiple channel wave frequencies by using generalized S transform,and obtain multiple velocity imaging results,which is used to optimize the velocity imaging effect of channel wave.The generalized S transform filtering is applied to a working face in Cheji Coal Mine,and the imaging results of amplitude attenuation coefficient are more accurate and clear than conventional processing.The generalized S transform multi-frequency velocity imaging is applied to the coal thickness inversion of Longwangzhuang Coal Mine.By comparing with the actual exposure,it is proved that the generalized S transform time-frequency analysis has high accuracy in coal thickness inversion.