【摘要】 利用PPP动态定位技术对地震时期的GPS观测数据进行处理,获得了各测站瞬时的地震地表形变信息。为了削弱PPP定位结果中残留的具有时空相关性的系统误差,采用空间叠加法和恒星日滤波法对PPP定位结果进行了后处理。为了验证两种方法在地震形变监测处理中的有效性,分别对美国圣西蒙地震和汶川地震的GPS观测数据进行了分析,实验结果表明,两种方法均能有效地削弱PPP动态定位中残留的系统误差,从而能更准确地提取地震形变信息。更多还原

【Abstract】 In order to obtain the displacements of observation points,high-rate GPS data sets are utilized to compute the positions epoch-by-epoch with precise point positioning (PPP) techni-que. However,the precision of PPP technology is affected by systematic errors that are not currently modeled. This paper investigates high-rate GPS positioning time series and describes methods for weakening these effects. Spatial stacking and sidereal filtering methods are introduced to improve the PPP positioning results. Some high-rate GPS observation data at permanent sites from San Simeon earthquake in America and Wenchuan earthquake in China,respectively,are calculated and analyzed. Numerical results demonstrate that stacking method could efficiently eliminate spatial correlation error between stations. While sidereal filtering has positive effect on removing multipath error. Both methods could be used in reducing positioning noise involved in PPP,and make it easier to accurately detect weak earthquake signals.更多还原