Ground station considerations for the AMOS satellite programme

NTNU centre for Autonomous Maritime Operations and Systems (AMOS) is expanding with a satellite programme (AMOS-Sat). These satellites will operate with frequencies ranging from VHF to low SHF. To support these future satellites, NTNU will need more resources in the ground station segment. To get experience with research, development and maintenance of ground stations, these should be built, tested and used to conduct research. For easy access to and distribution of satellite data, a network service must be considered. An alternative to high cost commercial solutions is an open ground station network. A survey of such platforms is conducted. One of the platforms, SatNOGS, is further explored by setting up a VHF/UHF network node. This network node has tracked and recorded over 200 satellite passes during the spring of 2017. The build and verification of the VHF/UHF ground station is presented. The results are used to form a link budget. It shows that the ground station can support orbits up to 400 km for VHF and up to 500 km for UHF in 99\% of all fading cases. The results from SatNOGS show that the station can support much higher orbits but may become scintillation limited. Finally, a novel idea for a low SHF ground station to support the AMOS-Sat endeavour is presented. The ground station is based on an adaptive polarisation SDR platform, and supports up- and downlink over 1 GHz to 6 GHz. The ground station for VHF/UHF and future expansion to the GHz range gives NTNU the needed experience in ground station operation. This, together with the potential for an open global network that SatNOGS provides, gives AMOS-Sat a low-cost alternative to commercial ground station services