槽波探测中谐波噪声的自适应衰减算法研究

Study on algorithm of harmonic noise adaptive attenuation in channel waves

为了解决槽波数据中检波器谐波成分较多,影响槽波探测准确性的问题,分析了谐波噪声的成因,提出了井下槽波谐波噪声的自适应衰减方法,在共接收点道集上对异常频率进行自适应滤波,在不损坏槽波的前提下消除每个检波器的谐波成分。采用工作面内陷落探测工程中实际采集的透射槽波数据验证方法有效性,结果表明:所提方法能够有效抑制槽波中的谐波噪声,增强透射槽波的整体品质,提高CT成像结果的准确度,实验数据中谐波干扰引起的能量衰减系数由0.058降至0.035,减少了谐波噪声对陷落柱成像结果的影响。

In order to resolve the problem of redundant harmonic noise exist in data of underground channel wave and affect the accuracy of the channel wave detection, we analyzed the cause of harmonic noise on geophones, and propose a method to adaptive attenuate harmonic noise on underground geophoues. The method adaptive filter out the abnormal frequency on common receiver gather, and eliminate harmonic components of singles come from each detector without damaging the channel wave. The method has been applied in a detection of sink- holes in a coal mining face. The result showed it could effectively reduce harmonic components of data from geophones,improve the quality of transmitted channel wave and the accuracy of CT result,decrease the noise caused energy attenuation coefficient of the experimental data from O. 058 to 0. 035, and reduce the influence of the noise of harmonic wave on geophones to the image of sinkholes.