Multi-frequency multi-GNSS receiver antenna calibration at IfE: Concept-calibration results-validation

Multi-frequency and multi-constellation GNSS have the potential to boost the overall performance of GNSS-based positioning, navigation and timing. This has an impact on the realisation of global reference frames, geophysical monitoring applications as well as enabling new applications. To this end, all error sources should be adequately corrected for. However, currently multi-frequency multi-GNSS receiver antenna calibration values are still missing. In this paper, the newly developed multi-frequency multi-GNSS calibration process at Institut fu spacing diaeresis r Erdmessung (IfE), Leibniz University Hannover, is presented. The basic concept and the assumptions for the antenna calibration are described. Resulting phase centre corrections (PCC) for GPS and Galileo for typical antennas are presented. We show that the repeatability of the estimated patterns are almost better than 2 mm in terms of maximum deviation and that the used tracking strategies by the receivers have marginal impact on the patterns, at maximum 1.2 mm for the studied receiver-antenna combinations. Furthermore, applying phase centre corrections for multi-frequency multi-GNSS carrier phase observations reduces significantly (up to 37%) the antenna related biases as validated on short baselines. Moreover, a validation in the coordinate domain shows that with IfE PCC a short baseline can be computed with high accuracy: the topocentric coordinate differences to the known baseline are in most cases smaller than 1 mm for the horizontal components and smaller than 2.2 mm in vertical. (c) 2021 COSPAR. Published by Elsevier B.V. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/).