CommunicationPublished on 18 March 2021

Quality assurance and usage statistics

The quality of the swipos services is monitored by several Integrity Monitoring (IM) stations. The stations – just like regular users - regularly establish a connection to the swipos-GIS/GEO service and measure their position. By comparing the measured position with the known position, quality of the service can be determined.

Distribution of the integrity monitoring stations in Switzerland and their installation state

Of the seven planned IM stations, five have been in operation since summer 2020 (Bière, Wangen a. A., Elgg, Monte Ceneri and Chur). Two more (Sion and Erstfeld) will follow by mid-2021. The IM stations are spread all over Switzerland in such a way, that they can monitor the swipos service comprehensively: in different elevations and different places.

The following tables show the minimum, maximum and mean deviations from the target values in position and height as well as their standard deviations for the period from October 5^th to 12^th 2020.

Problems with the mobile phone connection at some stations explain the different number of measurements across the stations.

In general, both the mean values of the deviations and the standard deviations meet the specifications of swipos (95% of all measurements within ± 2 cm in position and within ± 4 cm in height). However, the minimum and maximum deviations also clearly show that individual measurements can lie outside the tolerance.

In addition to the IM stations, we analyzed the usage of swipos. The anonymized statistics show the spatial and temporal usage of the swipos services in 2020. Their analysis will help us to make good decisions on the technical design of swipos (e.g. station density, measures to increase availability, etc.). 

Spatial usage statistics of swipos in 2020