GPS坐标时间序列中的异常高频周期性噪声

Anomalous high frequency seasonal noises in GPS positions time series

本文分析了中国地壳运动观测网络GPS基准站及中国周边IGS连续站坐标中的周期性噪声,在北、东和垂向分量坐标时间序列中均发现了周期约351/n(n=1,…,6)天的正弦项,而地表质量负荷造成的位移序列中并没有对应的成分,不能解释异常周期项的来源。在估计台站的运动速率时,如考虑此类"异常"周期项,速率误差略微减小,而周年项振幅的估计误差显著增大,且残差离散度未见明显改善。因此,不推荐在GPS速率矢量反演中加入异常周期项参数。

The seasonal noises in time series were analyzed for fiducial GPS sites in Crustal Movement Observation Network of China and continuous IGS GPS stations around China. It was found that there were sinusoids with periods around 351/n （ n = 1, …, 6） clays in positions time series for north, east and vertical components. These periodicities cannot be found in the displacements caused by Earth surface mass redistribution and their origins still await investigations. Taking into account these anomalous seasonal signals in estimation of rate resulted in a smaller improvement of rate uncertainty; however, the errors of annual amplitudes increased sharply and the RMS of residual time series were seldom improved. Consequently, it is not recommended to include these terms when deriving GPS velocity vectors.