重力极潮的小波分析  

Wavelet Approach to Study Gravity Pole Tide

作　　者：徐华君[1,2] 柳林涛[1] 许厚泽[1] 胡小刚[1] 

机构地区：[1]中国科学院测量与地球物理研究所,武汉市430077 [2]中国科学院研究生院,北京市100039

出　　处：《武汉大学学报（信息科学版）》2008年第11期1114-1117,共4页Geomatics and Information Science of Wuhan University

基　　金：国家自然科学基金资助项目(40574009)

摘　　要：分别分析Brussels台站的观测记录，首先扣除数据序列中的合成潮得到重力残差，接着用小波带通滤波器将残差滤波，得到256-512d时间尺度上的序列，然后运用最小二乘法估算Chandler和周年项的潮汐因子。由于小波滤波器能更有效地消除仪器漂移，计算结果具有更小的均方差，更加可靠。Wavelet analysis for filtering is used to improve estimation of gravity variations induced by Chandler and annual wobble. This method eliminates noise in superconducting gra vimeter （SG） records with band pass filters derived from Daubechies wavelet. The SG re cords at Brussels are analyzed. First, the Earth tides are removed from the observed data by using synthetic tides, and then the gravity residuals are filtered into a narrow period band of 256-512 d by a wavelet band pass filter. These data are submitted to least-square method for estimating the gravimetric factor of the Chandler and annual wobble. After processed by wavelet filtering, SG records can provide amplitude factors δ and phase lags κ of the two wobbles with much smaller mean square deviation （MSD） than these provided by former studies. It is mainly because the wavelet method can effectively eliminate instrumental drift and provide smoothed data series for the regression analysis.

关 键 词：小波滤波 重力长期变化 极潮 重力残差 

分 类 号：P223.7[天文地球—大地测量学与测量工程]