Wavelet theory is efficient as an adequate tool for analyzing single epoch GPS deformation signal. Wavelet analysis technique on gross error detection and recovery is advanced. Criteria of wavelet function choosing an...Wavelet theory is efficient as an adequate tool for analyzing single epoch GPS deformation signal. Wavelet analysis technique on gross error detection and recovery is advanced. Criteria of wavelet function choosing and Mallat decomposition levels decision are discussed. An effective deformation signal extracting method is proposed, that is wavelet noise reduction technique considering gross error recovery, which combines wavelet multi-resolution gross error detection results. Time position recognizing of gross errors and their repairing performance are realized. In the experiment, compactly supported orthogonal wavelet with short support block is more efficient than the longer one when discerning gross errors, which can obtain more finely analyses. And the shape of discerned gross error of short support wavelet is simpler than that of the longer one. Meanwhile, the time scale is easier to identify.展开更多
When the deformation of landslide becomes larger, the conventional static GPS surveying cannot satisfy the real-time requirement in landslide monitoring. In this paper we present a new method for single epoch GPS posi...When the deformation of landslide becomes larger, the conventional static GPS surveying cannot satisfy the real-time requirement in landslide monitoring. In this paper we present a new method for single epoch GPS posi- tioning combining with the accuracy of approximate coordinates of monitored station in landslide monitoring. This algorithm does not consider troublesome cycle-slip problem of carrier phase, and integer ambiguities can be solved at a single epoch, so the centimeter level accurate coordinates can be calculated instantaneously. By means of fil- tering or smoothing, this method can be extended to detect millimeter level deformation and velocity. In order to test the new method, low-cost single frequency receivers have been used in a real landslide, which happened in Jiangxi Province, China.展开更多
基金Supported by Specialized Research Fundfor the Doctoral Programof Higher Educationin China(No.20040290503) Science and Technology Fundationof CUMT(No.2005B020) .
文摘Wavelet theory is efficient as an adequate tool for analyzing single epoch GPS deformation signal. Wavelet analysis technique on gross error detection and recovery is advanced. Criteria of wavelet function choosing and Mallat decomposition levels decision are discussed. An effective deformation signal extracting method is proposed, that is wavelet noise reduction technique considering gross error recovery, which combines wavelet multi-resolution gross error detection results. Time position recognizing of gross errors and their repairing performance are realized. In the experiment, compactly supported orthogonal wavelet with short support block is more efficient than the longer one when discerning gross errors, which can obtain more finely analyses. And the shape of discerned gross error of short support wavelet is simpler than that of the longer one. Meanwhile, the time scale is easier to identify.
基金Open Foundation of Key Laboratory of Dynamic Geodesy, Chinese Academy of Sciences (L04-07), National Natural Science Foundation of China (40474010) and Project of Science and Technology Bureau of Sichuan Province (02GG006-048).
文摘When the deformation of landslide becomes larger, the conventional static GPS surveying cannot satisfy the real-time requirement in landslide monitoring. In this paper we present a new method for single epoch GPS posi- tioning combining with the accuracy of approximate coordinates of monitored station in landslide monitoring. This algorithm does not consider troublesome cycle-slip problem of carrier phase, and integer ambiguities can be solved at a single epoch, so the centimeter level accurate coordinates can be calculated instantaneously. By means of fil- tering or smoothing, this method can be extended to detect millimeter level deformation and velocity. In order to test the new method, low-cost single frequency receivers have been used in a real landslide, which happened in Jiangxi Province, China.
