A major error source for precise GNSS applications are station dependent errors arising from multipath effects.
An in-situ station calibration approach has been proposed by Wübbena et al. (2011), based on a combination of
several strategies to separate the near-field (NF) multipath for a single station to the best.
The basic station calibration concepts of analyzing observation residuals can also be applied to data from
reference stations in RTK-networks. Based on elevation and azimuth dependent residuals (EAR) the calibration
patterns as well as variance component estimates (VCE) are derived for each individual station. The EAR-VCE
station calibration uses phase, code and signal-to-noise observables for every GNSS frequency. The station
calibration results can be applied in the GNSS processing to improve the network performance as well as the
performance of rovers utilizing the different network services.