Simulation and emulation of the 5G Non-Terrestrial Network Radio Access Network with Open Air Interface

The integration of Non-Terrestrial Networks (NTN) into the 5G ecosystem represents a transformative advancement in telecommunications, offering extended coverage, enhanced accessibility, and support for critical applications in areas where traditional infrastructure is limited or impractical. In this context, network virtualization emerges as a key enabler for integrating 5G technology into NTN, decoupling network functions from hardware and implementing them as software instances. This thesis focuses on the development and emulation of an NTN Radio Access Network (RAN) using Open Air Interface (OAI), an open-source, software-based RAN and Core Network (CN) implementation. Through the description of a testbed developed during an internship at the European Space Research and Technology Centre (ESTEC) of the European Space Agency (ESA), the thesis illustrates the design, implementation, and testing of a Standalone (SA) 5G network capable of providing both terrestrial and non-terrestrial coverage. By presenting the development of this testbed, the thesis demonstrates how open-source and virtualized technologies, combined with the necessary hardware components, contribute to advancing 5G integration within NTN, paving the way for more flexible, scalable, and accessible telecommunications systems.