Fixing method of ambiguity network between CORS and system station

Abstract

The invention discloses a fixing method of an ambiguity network between CORS system stations, which comprises the following steps: first, a wide-lane ambiguity float solution is worked out with the linear combination of carrier wave and pseudorange, the mean is solved through multi-epoch according to the long-wave features of wide-lane ambiguity, to determine the wide-lane ambiguity integer solution; and then the delay dry weight of a troposphere is estimated through a Neill model, L1 ambiguity is separated by the independent combination of an ionosphere, so as to determine L2 ambiguity; and finally accuracy test of ambiguity resolution is carried out. The method provided by the invention can fix the baseline ambiguity between CORSs in a short time, is quick, stable and easy to be implemented in projects.

Description

technical field [0001] The invention relates to a method for solving a baseline integer ambiguity network between reference stations in a GNSS network differential positioning system, in particular to a continuous operation reference station (CORS) system inter-station integer ambiguity network fixing method, belonging to the field of GNSS network differential positioning. Background technique [0002] GNSS network differential positioning technology is currently a popular technology in the field of satellite positioning. It is widely used in surveying and mapping, land and resources survey and other industries. The rise of network differential technology represented by virtual reference station technology (VRS) has enabled the establishment of a reference station network GPS service system. Become the latest trend in the development of current GPS technology applications. As a GPS real-time dynamic positioning technology in a multi-reference station environment, VRS technol...

AI Technical Summary

Problems solved by technology

With the increase of the baseline distance between reference stations, the correlation of systematic errors weakens or even disappears, and the systematic error residuals in the double-difference observations increase rapidly, which makes it difficult to correctly determine the ambiguity of the whole circle, which reduces the positioning accuracy. The online fixation of the ambiguity of the medium and long baselines is an important technical issue that restricts the real-time performance and reliability of VRS / RTK

Many scholars at home and abroad have carried out a lot of research work on medium and long baseline ambiguity resolution methods, mainly including the following methods: 1. Gao Xingwei proposed a single-epoch whole-circle ambiguity search method between reference stations (Gao Xingwei, 2002). The main idea of ​​the method is not to solve the equations, and directly use the three conditions of known station coordinates, integer ambiguity and linear relationship between dual-frequency integer ambiguities to search, but its principle is not perfect and reliable. Therefore, this method has not been widely used; 2. Zhou Letao’s fast integer ambiguity resolution is another effective long-baseline ambiguity fixing method (Zhou Letao, 2006), and its solution idea is to use parallel filtering and wave spreading technology (Sun , 1999; Chen, 2000): First, the Kalman filter is performed on the wide-lane ambiguity and the ionosphere-independent ambiguity in parallel. Due to the long-wave characteristics of the wide-lane, it must be solved first in the filtering process, and then substituted into the ionization The layer-independent combination makes the wavelength of the ionosphere-independent combination expanded from 0.006m to 0.107m. Finally, the ambiguity is fixed and the parameter fixed solution is calculated by estimating the zenith tropospheric delayed wet component and the integer estimation of the L1 ambiguity. The method has extremely high requirements for model parameters in Kalman filtering

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