An analysis for irregularity of tropospheric delay error between network stations during local atmospheric change

Abstract

Network RTK (Real Time Kinematic) is a precise positioning technique using CPC (Carrier Phase Correction) from reference stations within the network. The principle of network RTK is that corrections between reference stations are estimated, and this information is provided to rovers in the field [1]. Rovers can improve the positioning accuracy at the user position, through an interpolation process of the acquired corrections [2]. To serve the high-quality corrections for any rover within the network's coverage, the receiver on the reference station needs to acquire raw measurements of good quality, and the environmental factors between the network stations must be assessed. Generally, the correction concept on network RTK is that the error components on a reference station are known, and the spatially correlated errors, such as the ionosphere, troposphere and orbit errors, are compensated by an interpolation technique due to the linearly dependent errors on distance. But unfortunately, in the presence of local atmospheric change, such as typhoons or regional torrential rain, large tropospheric residuals remain even with Network RTK. In this paper, we defined the irregularity of tropospheric delay error between the network stations by the locally extreme atmosphere change. And, the influence of tropospheric delay irregularity between the network stations and the atmosphere conditions at this point are analyzed using the gathered meteorological data.