处理了2000-01~2012-06的VLBI观测数据,提取了ERP地球自转参数信息,通过JPL的DE405星历计算得到了2000-01~2012-06的月地距时间序列;消除日长变化、极移和月地距时间序列趋势项,采用频谱分析的方法求得它们的周期;根据解算的周期推测日长变化和日地距可能存在相关性,并验证了推测。
ERP(earth rotation parameter) was got through the handing of the 2000-01-2012-06VLBI data;the time series of distance of the Moon and Earth by JPL(Jet Propulsion Laboratory) ephemeris was calculated.The trend of ERP and the Earth-to-Moon distance is removed,and the periods of them are calculated with spectral analysis.The correction between the Earth-to-Moon distance and the periodic components of ΔLOD(change in length of day)extracted by wavelet analysis is analyzed,which would make sense in the prediction of ERP based on the planetary ephemeris.