A Real Time Algorithm to Monitor GNSS Positioning Services

The aim of permanent networks is to provide network correction information to RTK or Static rover users to derive their positions with a higher accuracy. The proposed algorithm was tested on a network of permanent networks belonging to Leica SmartNetItalPoS. The leave one out statistical method was applied. Two controls were implemented in the process. Control 1 (C1) in which the excluded station is estimated in real time by using the surrounding stations and the network products and in control 2 (C2), network products are used to simulate data of a virtual user in the position of the excluded station. Several experiments were performed to test the algorithm using different network configurations and imposed errors in height to understand the effectiveness of the controls. For imposed errors in the height, C1 provided exactly the expected results, with a bias in the estimates almost equal to the introduced error in the reference station and the results variations depended on network configuration. C2 failures increase significantly with the error increase, but the errors of fixed estimates are not linearly dependent on it. The study recommends further experiments in other reference frames and a future improvement on the proposed algorithm.