Satellite and Terrestrial Multi-Connectivity for 5G: Making Spectrum Sharing Possible
This paper reports the first results of the 5G- ALLSTAR project  aiming at providing solutions and enablers for spectrum sharing in a 5G cellular and satellite multi-connectivity context. First, we present an exhaustive study of the frequency bands eligible for these systems in the short and medium term. A ray-tracing based and a geometry-based stochastic channel models developed in the project are then described. These models can be used to simulate systems involving terrestrial and non- terrestrial networks. We then describe three different ways investigated in the project for managing interference: signal processing (hardware implementation of a 5G New Radio compatible physical layer), beamforming (steering and switching beams in order to avoid the interference while preserving the spectral efficiency) and radio resource management (tool designed for joint optimization of satellite and terrestrial resource sharing).