An Analysis for Irregularity of Tropospheric Delay due to Local Weather Change Effects on Network RTK

Abstract

-Network RTK generates spatial corrections by using differenced measurements from reference stations in the network, and the corrections are then provided to a rover. The rover, generally, uses linear interpolation, which assumes that the corrections at each reference station are spatially correlated, to obtain a precise correction of its location. However, an irregularity of the tropospheric delay is a real-world factor that violates this assumption. Tropospheric delay is a result of weather conditions, such as humidity, temperature and pressure, and it can cause spatial decorrelation when there are changes in the local climate. In this paper, we have defined the non-linear characteristics of the tropospheric delay between reference stations or user within a region as the "irregularity of tropospheric delay". Such an irregularity can negatively impact the network RTK performance. Therefore, we analyze the influence of the irregularity of tropospheric delay in network RTK based on meteorological data.

Tropospheric Anomaly Detection in Multi-reference Stations Environment during Localized Atmosphere Conditions-(1) : Basic Concept of Anomaly Detection Algorithm

“…If it is assumed that the network has enough short baseline, the tropospheric delay at the rover position would be similar because the weather conditions at the rover position also would be similar with the reference stations. However, predicting the tropospheric delay at the rover position when the baseline becomes longer is needed (Han, 2014). This paper proposes a detection algorithm for tropospheric anomalies and anomalous satellites that can degrade the correction message quality in use of reference station networks.…”

Tropospheric Anomaly Detection in Multi-Reference Stations Environment during Localized Atmospheric Conditions-(2) : Analytic Results of Anomaly Detection Algorithm

“…Tropospheric anomaly can be caused by localized atmospheric conditions between reference stations in network RTK (real-time kinematic) environment, and it becomes one of the limiting factors for precise positioning (Ahn, 2007;Han, 2014). Inhomogeneous atmospheric conditions can affect the network solution and an imbalanced network error can degrade the correction message to rover station.…”