基于全球导航定位系统的后处理动态差分(Post Process Kinetic,PPK)可在事后为用户提供厘米级甚至更高精度的定位服务。相比于实时动态差分(Real-Time Kinetic,RTK),PPK牺牲了实时性,但减少了对通信的依赖,且可使用双向的数据预处理及...基于全球导航定位系统的后处理动态差分(Post Process Kinetic,PPK)可在事后为用户提供厘米级甚至更高精度的定位服务。相比于实时动态差分(Real-Time Kinetic,RTK),PPK牺牲了实时性,但减少了对通信的依赖,且可使用双向的数据预处理及滤波算法来提升定位效果。为了提升PPK的长基线定位效果,笔者提出一种多次滤波PPK处理方法。该方法提升了参数收敛速度,缩短了滤波过程中的首次固定时间,提供了更优的定位结果。为了验证该技术的定位效果,笔者在黄海海域进行了动态实验。实验结果显示,新的滤波方法将北、东和天顶3个方向的定位精度分别提升了59.2%、36.1%、70.3%。展开更多
In this research, we present a seismic trace interpolation method which uses seismic data with surface-related multiples. It is different from conventional seismic data interpolation using information transformation o...In this research, we present a seismic trace interpolation method which uses seismic data with surface-related multiples. It is different from conventional seismic data interpolation using information transformation or extrapolation of adjacent channels for reconstruction of missing seismic data. In this method there are two steps, first, we construct pseudo-primaries by cross-correlation of surface multiple data to extract the missing near- offset information in multiples, which are not displayed in the acquired seismic record. Second, we correct the pseudo-primaries by applying a Least-squares Matching Filter （LMF） and RMS amplitude correction method in time and space sliding windows. Then the corrected pseudo-primaries can be used to fill the data gaps. The method is easy to implement, without the need to separate multiples and primaries. It extracts the seismic information contained by multiples for filling missing traces. The method is suitable for seismic data with surfacerelated multiples.展开更多
The filter operator used in normal multichannel matching filter is physically realizable. This filter operator only delays seismic data in the filtering process. A non- causal multichannel matching filter based on a l...The filter operator used in normal multichannel matching filter is physically realizable. This filter operator only delays seismic data in the filtering process. A non- causal multichannel matching filter based on a least squares criterion is proposed to resolve the problem in which predicted multiple model data is later than real data. The differences between causal and non-causal multichannel matching filters are compared using a synthetic shot gather, which demonstrates the validity of the non-causal matching filter. In addition, a variable length sliding window which changes with offset and layer velocity is proposed to solve the count of events increasing with increasing offset in a fixed length sliding window. This variable length sliding window is also introduced into the modified and expanded multichannel matching filter. This method is applied to the Pluto1.5 synthetic data set. The benefits of the non-causal filter operator and variable length sliding window are demonstrated by the good multiple attenuation result.展开更多
文摘基于全球导航定位系统的后处理动态差分(Post Process Kinetic,PPK)可在事后为用户提供厘米级甚至更高精度的定位服务。相比于实时动态差分(Real-Time Kinetic,RTK),PPK牺牲了实时性,但减少了对通信的依赖,且可使用双向的数据预处理及滤波算法来提升定位效果。为了提升PPK的长基线定位效果,笔者提出一种多次滤波PPK处理方法。该方法提升了参数收敛速度,缩短了滤波过程中的首次固定时间,提供了更优的定位结果。为了验证该技术的定位效果,笔者在黄海海域进行了动态实验。实验结果显示,新的滤波方法将北、东和天顶3个方向的定位精度分别提升了59.2%、36.1%、70.3%。
基金sponsored by:the National Basic Research Program of China (973 Program) (2007CB209605)the National Natural Science Foundation of China (40974073)the National Hi-tech Research and Development Program of China (863 Program) (2009AA06Z206)
文摘In this research, we present a seismic trace interpolation method which uses seismic data with surface-related multiples. It is different from conventional seismic data interpolation using information transformation or extrapolation of adjacent channels for reconstruction of missing seismic data. In this method there are two steps, first, we construct pseudo-primaries by cross-correlation of surface multiple data to extract the missing near- offset information in multiples, which are not displayed in the acquired seismic record. Second, we correct the pseudo-primaries by applying a Least-squares Matching Filter （LMF） and RMS amplitude correction method in time and space sliding windows. Then the corrected pseudo-primaries can be used to fill the data gaps. The method is easy to implement, without the need to separate multiples and primaries. It extracts the seismic information contained by multiples for filling missing traces. The method is suitable for seismic data with surfacerelated multiples.
基金supported by the National 863 Program (Grant No. 2006AA09A102-09)the National 973 Program (GrantNo. 2007CB209606)
文摘The filter operator used in normal multichannel matching filter is physically realizable. This filter operator only delays seismic data in the filtering process. A non- causal multichannel matching filter based on a least squares criterion is proposed to resolve the problem in which predicted multiple model data is later than real data. The differences between causal and non-causal multichannel matching filters are compared using a synthetic shot gather, which demonstrates the validity of the non-causal matching filter. In addition, a variable length sliding window which changes with offset and layer velocity is proposed to solve the count of events increasing with increasing offset in a fixed length sliding window. This variable length sliding window is also introduced into the modified and expanded multichannel matching filter. This method is applied to the Pluto1.5 synthetic data set. The benefits of the non-causal filter operator and variable length sliding window are demonstrated by the good multiple attenuation result.
