钱德勒摆动和周年极移参数从历元1965.0到1985.0的逐年变化  

VARIATIONS OF THE CHANDLER WOBBLE AND THE ANNUAL POLAR MOTION FROM 1965.0 TO 1985.0

作　　者：高布锡[1] 

机构地区：[1]中国科学院测量与地球物理研究所

出　　处：《天文学报》1990年第3期228-236,共9页Acta Astronomica Sinica

摘　　要：文中建议了一种新的付里叶变换反卷积方法.这种方法在频域有极高的分辨率,利用较短时间资料,便可求出对应于平均时刻的各个谱峰的周期,振幅及位相等数值. 文中对国际时间局(BIH)提供的从1962.0到1988.0的极移资料进行了分析,给出了从历元1965.0到1985.0的逐年的钱德勒摆动和周年极移参数.这些极移参数的逐年变化显示出许多有趣的极移特征.In this paper a new deconvolution method for Fourier transform is suggested. The main contents of this method are as follows. Firstly, the Hanning window function, which is considered to be band-limited in time and frequency domains, is used to truncate the original data. Secondly, a fourier analysis of the truncated is data made. Thirdly, the convolution equation is solved by use of successive approximations and the actual Fourier transform are obtained Finally, from the inverse Fourier transform of the derived actual Fourier transform we can exactly obtain the values corresponding to the period, amplitude and phase of the mean time of the truncated data. This method has very high resolution in the frequency domain only with shorter length data. In the third part of this paper, the polar motion data of the BIH from 1962.0 to 1988.0 are analysed with this method. Besides the parameters of the Chandler wobble and the annual polar motion that correspond to different epoches from 1965.0 to 1985.0 are obtained. From these results it can be seen that the amplitudes of both the Chandler wobble and the annual polar motion are not stable and that the pseudo-annual excitation may be the reason for containing the motion of the Chandler wobble.

关 键 词：极移 傅里叶变换 钱德勒摆动 运动 

分 类 号：P127.4[天文地球—天体测量]