基于DB小波阈值去噪的航空重力数据试验  

EXPERIMENTAL RESEARCHES ON THE THRESHOLD OF AIRBORNE GRAVITY DATA DENOISING BASED ON DB WAVELET TRANSFORM

作　　者：罗锋[1,2] 郭志宏[1,2] 王明[1,2] 骆遥[1,2] 王艳[1] 

机构地区：[1]中国国土资源航空物探遥感中心,北京100083 [2]中国国土资源航空物探遥感中心对地观测技术工程实验室,北京100083

出　　处：《物探与化探》2013年第4期645-654,共10页Geophysical and Geochemical Exploration

基　　金：中国国土资源航空物探遥感中心对地观测技术工程实验室课题(2010YFL004)

摘　　要：利用Mallat快速算法实现离散小波变换,选用DaubechiesN小波系为小波基函数,通过理论模型数据验证了方法设计的可靠性。在对实测航空重力数据进行去噪过程中,根据重力异常信号频带特点,采取多层分解和阈值策略进行自由空气重力异常的提取。试验进行了6～8层的分解,采用了强制阈值去噪和施加软阈值去噪,并进行了对比,结果表明基于DB小波阈值去噪所获得的自由空气重力异常与GT-1A系统滤波结果基本吻合。This paper proposes a method to compute the DWT （discrete wavelet transform） coefficients using Mallat＇s fast algorithm with Daubechies N （N = 1,..., 10） wavelet series as the wavelet primary function. The authors verified the reliability of the method with a theoretical model. By using an approach to multi-layer decomposition and a strategy of threshold value in the process of the airborne gravity data denoising, the authors extracted the free air gravity anomalies by the frequency and bandwidth character of the gravity a- nomalies. A comparison is made by using six, seven and eight layers decomposition and by employing the soft-threshold and the hard- threshold denoising. The results demonstrate that the free air gravity anomalies extracted by this method are quite consistent with the fil- tered results of the GT-1A system.

关 键 词：DB小波 异常分解 阈值选取 航空重力 

分 类 号：P631.1[天文地球—地质矿产勘探]