VGOS wideband reception and emerging competitor occupations of VLBI spectrum

The VGOS wideband receivers cover a spectrum from 2 to 14 GHz. In this range, many frequencies are allocated to other services. VGOS provides up to four 1 GHz wide sub-bands, which can be tuned to frequencies where detrimental radio frequency interference is absent. The increasing demand of commercial users of radio spectrum and related on-going telecommunication projects are threatening the VGOS observation plans. The examples of a compatibility study for 5G concerning the GermanWettzell site and the global availability of Starlink/OneWeb illustrate the impact on VGOS and the need of regulation by spectrum authorities. This article contains a brief introduction how spectrum management is organized and what needs to be done on the national level to achieve protection for VGOS sites.