2017–2018 Report of the IVS Associate Analysis Center PMD

The activities related to geodetic VLBI performed at the IVS AC PMD during 2017 and 2018 were focused on different topics that are detailedbelow. As in previous years, routine computations of European baselines were carried out. For the Ny-Alesund VLBI station detailed studies havebeen executed on velocity estimations and comparisons with results from geodetic satellite techniques.In parallel, investigations on running or preparing VGOS stations were developed. In particular, the RFI threat to the new broadband system, due to several new commercial services that operate in VGOS bands, was investigated. This work was developed also under the framework of the Committee on Radio AstronomyFrequencies (CRAF). From the observation point-of-view, AC PMD has coordinated the three Italian VLBI stations (Matera,Medicina, and Noto) for the realization of the experiments s7615b on phase referencing VLBI observationsof the Chang’E-3 lander. Another topic investigated at PMD was under the COST project Action ES1206. In particular, severalsimulations and comparisons of different algorithms developed to detect inhomogeneity in the GPS Inte-grated Water Vapor (IWV) time series were tested. These studies can be applied in the future also to theVLBI IWV time series.