PyGACT - a Python toolkit for determination of relative GNSS antenna phase center variations

, ICS | C 4.3

Evolvements of GNSS technology require that instrumental error sources are well understood and can be corrected in analysis. In particular, the antenna phase center of GNSS antennas must be accurately known for high accuracy applications. Such a correction requires the knowledge of the phase center offset (PCO) and the phase center variation (PCV). While absolute calibrations are available for high-end geodetic antenna, most of the low-cost mass-market antenna remain uncalibrated. Furthermore, the scientific Python ecosystem has been maturing rapidly in the past few years and an extensive collection of free libraries is now available. Thus, we have developed a Python toolbox called PyGACT, which allows to estimate relative PCO as well as PCV maps and analyze C/N0 and multi-path characteristics. PCV maps can be estimated in the form of spherical harmonics coefficients for which degree and order can be set by the user. In addition, we have implemented an option to derive PCV maps in the form of 2D B-splines, which allows to better adapt to the local satellite visibility conditions. In our presentation we will summarize the features of our software tool and we show results from relative antenna calibrations that range from low-lost hardware to geodetic grade equipment. Moreover, as our tool is capable to consider not only GPS and GLONASS frequencies, we also present relative PCV characteristics for Galileo, Beidou and QZSS signal reception.

Präsentation