Random Access Procedures for Narrow-Band Internet of Things via Non-Terrestrial Networks

The Internet of Things (IoT) is a fundamental pillar in the digital transformation since it enables the interaction with the physical world by means of sensing and actuation. 3GPP recognized the importance of IoT by introducing new features aimed at supporting this technology. In details, in Rel.13, the 3GPP has launched the NB-IoT to provide support for LPWAN. Since these devices will be distributed also in such area where the terrestrial networks are not feasible or commercially viable, satellite networks will have a complementary role thanks to their capability to provide worldwide connectivity through their large footprint size and short service deployment time. In this context, the aim of this thesis is to analyze the feasibility of integration of the NB-IoT technology with satellite communication systems focusing on the Random-Access Procedure. Indeed, the RA is the most critical procedure since it allows the UE to achieve uplink synchronization, obtain the permanent ID, and get the resources for the uplink transmission. The objective of the thesis is the assessment of the preamble detection in the SatCom environment. The elaborate is divided in four chapters: the first one highlights the main characteristics of the NBIoT technology. In the second chapter, a detail description of the synchronization and RA procedures is presented with a review of the Stat of Art of the detection of the preamble; in the third chapter the main features of SatCom systems are shown, with particular emphasis on the impairments which could hamper the RA procedure. In the fourth chapter, a thorough analysis on the detection process and the implementation of the transmission and reception chain, obtained by the means of simulator built in MATLAB, are provided, with the results. Finally, chapter five concludes this work.