A new similar single-difference mathematical model (SS-DM) and its corresponding algorithmare advanced to solve the deformationof monitoring point directly in singleepoch. The method for building theSSDM is introduced...A new similar single-difference mathematical model (SS-DM) and its corresponding algorithmare advanced to solve the deformationof monitoring point directly in singleepoch. The method for building theSSDM is introduced in detail, and themain error sources affecting the accu-racy of deformation measurement areanalyzed briefly, and the basic algo-rithm and steps of solving the deform-ation are discussed.In order to validate the correctnessand the accuracy of the similar single-difference model, the test with fivedual frequency receivers is carried outon a slideway which moved in plane inFeb. 2001. In the test,five sessions areobserved. The numerical results oftest data show that the advanced mod-el is correct.展开更多
Based on the analyses for the characteristics of high precise GPS defor-mation monitor,according to the spatial relationship among the satellite, base point and monitoring point a new model and its corresponding algor...Based on the analyses for the characteristics of high precise GPS defor-mation monitor,according to the spatial relationship among the satellite, base point and monitoring point a new model and its corresponding algorithm were presented to solve the monitoring point deformation directly at single epoch. In this method the carrier phases is used as the basic observations, and the initial condition is precise baseline vectors obtained in the first period observations between the base point and monitoring point. This model is called the similar single difference model (SSDM). The main error sources effecting the accuracy of deformations were analyzed briefly, the single epoch algorithm of the receiver clock offset was advanced. The numerical results of test data show that the SSDM and the single epoch algorithm of receiver clock offset advanced are reliable and correct.展开更多
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
Using similar single-difference methodology(SSDM) to solve the deformation values of the monitoring points, there is unstability of the deformation information series, at sometimes.In order to overcome this shortcomin...Using similar single-difference methodology(SSDM) to solve the deformation values of the monitoring points, there is unstability of the deformation information series, at sometimes.In order to overcome this shortcoming, Kalman filtering algorithm for this series is established,and its correctness and validity are verified with the test data obtained on the movable platform in plane. The results show that Kalman filtering can improve the correctness, reliability and stability of the deformation information series.展开更多
鉴于传统的位移监测实验模式存在诸多弊端,本文设计了一种基于北斗的高精度位移监测创新试验平台。首先,建立北斗单历元定位数学模型,给出一种适用于北斗多频信号主辅频相关法(MAXCOM)的整周模糊度快速解算流程;然后,基于Visual Studio ...鉴于传统的位移监测实验模式存在诸多弊端,本文设计了一种基于北斗的高精度位移监测创新试验平台。首先,建立北斗单历元定位数学模型,给出一种适用于北斗多频信号主辅频相关法(MAXCOM)的整周模糊度快速解算流程;然后,基于Visual Studio 2019开发平台,运用C#编程语言,研制一种北斗高精度位移监测创新试验平台(LSMS)。试验测试与分析结果表明,LSMS试验平台的北斗位移监测精度可达厘米级,其中北向精度优于0.9 cm,东向精度优于1.2 cm,垂直精度优于3.0 cm,水平精度优于1.5 cm,点位精度优于3.3 cm。本文方法及试验平台用于北斗高精度位移监测创新试验是行之有效的。展开更多
We study on reduced dynamic orbit determination using differenced phase in adjacent epochs for spacebome dual-frequency GPS. This method not only overcomes the shortcomings that the epoch-difference kinematic method c...We study on reduced dynamic orbit determination using differenced phase in adjacent epochs for spacebome dual-frequency GPS. This method not only overcomes the shortcomings that the epoch-difference kinematic method cannot be used when observation geometry is poor or observations are insufficient, but also avoids solving the ambiguity in the zero-difference reduced dynamic method. As the epoch-difference method is not sensitive to the impact of phase cycle slips, it can lower the difficulty of slip detection in phase observation preprocessing. In the solution strategies, we solve the high-dimensional matrix computation problems by decomposing the long observation arc into a number of short arcs. By gravity recovery and climate experiment (GRACE) satellite orbit determination and compared with GeoForschungsZentrum (GFZ) post science orbit, for epoch-difference reduced dynamic method, the root mean squares (RMSs) of radial, transverse and normal components are 1.92 cm, 3.83 cm and 3.80 cm, and the RMS in three dimensions is 5.76 cm. The solution's accuracy is comparable to the zero-difference reduced dynamic method.展开更多
基金the National Land and Resource Bureau Science and Technology Foundation (No. 20001020304).
文摘A new similar single-difference mathematical model (SS-DM) and its corresponding algorithmare advanced to solve the deformationof monitoring point directly in singleepoch. The method for building theSSDM is introduced in detail, and themain error sources affecting the accu-racy of deformation measurement areanalyzed briefly, and the basic algo-rithm and steps of solving the deform-ation are discussed.In order to validate the correctnessand the accuracy of the similar single-difference model, the test with fivedual frequency receivers is carried outon a slideway which moved in plane inFeb. 2001. In the test,five sessions areobserved. The numerical results oftest data show that the advanced mod-el is correct.
基金Doctor Foundation of Anhui University of Science and Technology.
文摘Based on the analyses for the characteristics of high precise GPS defor-mation monitor,according to the spatial relationship among the satellite, base point and monitoring point a new model and its corresponding algorithm were presented to solve the monitoring point deformation directly at single epoch. In this method the carrier phases is used as the basic observations, and the initial condition is precise baseline vectors obtained in the first period observations between the base point and monitoring point. This model is called the similar single difference model (SSDM). The main error sources effecting the accuracy of deformations were analyzed briefly, the single epoch algorithm of the receiver clock offset was advanced. The numerical results of test data show that the SSDM and the single epoch algorithm of receiver clock offset advanced are reliable and correct.
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.
文摘Using similar single-difference methodology(SSDM) to solve the deformation values of the monitoring points, there is unstability of the deformation information series, at sometimes.In order to overcome this shortcoming, Kalman filtering algorithm for this series is established,and its correctness and validity are verified with the test data obtained on the movable platform in plane. The results show that Kalman filtering can improve the correctness, reliability and stability of the deformation information series.
基金National Natural Science Foundation of China (61002033, 60902089) Open Research Fund of State Key Laboratory of Astronautic Dynamics (2011ADL-DW0103)
文摘We study on reduced dynamic orbit determination using differenced phase in adjacent epochs for spacebome dual-frequency GPS. This method not only overcomes the shortcomings that the epoch-difference kinematic method cannot be used when observation geometry is poor or observations are insufficient, but also avoids solving the ambiguity in the zero-difference reduced dynamic method. As the epoch-difference method is not sensitive to the impact of phase cycle slips, it can lower the difficulty of slip detection in phase observation preprocessing. In the solution strategies, we solve the high-dimensional matrix computation problems by decomposing the long observation arc into a number of short arcs. By gravity recovery and climate experiment (GRACE) satellite orbit determination and compared with GeoForschungsZentrum (GFZ) post science orbit, for epoch-difference reduced dynamic method, the root mean squares (RMSs) of radial, transverse and normal components are 1.92 cm, 3.83 cm and 3.80 cm, and the RMS in three dimensions is 5.76 cm. The solution's accuracy is comparable to the zero-difference reduced dynamic method.