An Ecosystemic Approach for the Seamless Integration of Terrestrial and Non-Terrestrial Network Connections

An unrestricted, global, and ubiquitous connectivity, available to anyone, everywhere, and anytime, is a key objective of the 6G vision. A true, seamless integration of terrestrial (T) and non-terrestrial (NT) networks is mandatory to reach such an ambitious target. From this perspective, the three-year ITA-NTN project (2023-2025), funded by the European Union within the framework of NextGenerationEU work program, aims to investigate advanced solutions for the seamless integration of Terrestrial and Non-Terrestrial networks. This paper considers the project aspects concerning the provision of seamless connectivity across the heterogeneous T and NT layers by proposing an integrated ecosystem, which enables transparent information exchange among the various communicating nodes belonging to each layer. The ecosystem relies on the software-based management of fully reconfigurable network architectures based on disruptive concepts like cell-free multiple-input multiple-output (MIMO), full software-defined radio (SDR)-based multi-waveforms physical layer design, use of aggressive capacity-oriented radio resource management strategies based on Non Orthogonal Multiple Access (NOMA), extended use of Software-Defined Networking (SDN), and Artificial Intelligence (AI) to monitor and manage the entire network architecture. The discussion of the achieved results validates the proposed ecosystemic approach both in terms of viability and quantitative performance improvement.