Effect of network geometry on determination of VLBI-GNSS frame orientation using a VLBI transmitter onboard Galileo satellites

Having a Very Long Baseline Interferometry (VLBI) transmitter (VT) onboard Galileo satellite allows us to determine the misorientation between GNSS and VLBI frames. To exploit the maximum performance, we study the operational strategies for VLBI ground segment. We simulate VLBI observations of a VT onboard a Galileo satellite to evaluate the rotation transformation between the VLBI and GNSS frames. The contribution of a VT as space tie is assessed by the evaluation of the formal precision of the orientation parameters between the VLBI and GNSS frames using different ground stations/baselines, aiming to find the optimal observation geometry for the best precision on the rotation transformation.