Investigating the applicability of LTE-M for Network Identification of Unmanned Aerial Systems in U-Space

Unmanned Aerial System (UAS) Traffic Management (UTM) is a key enabler for unleashing the full potential of the UAS technology. Europe is currently in the progress of implementing the initial services of the U-Space framework, the European Union (EU) version of UTM. With the Commission Implementing Regulation (EU) 2021/664 now in force, defining the regulatory framework for U-Space, the establishment of U-spaces in EU will soon be a reality in some countries.In this paper, a stand-alone component, named DroneID5G, is designed to comply with the Network Identification (ID) service specified in 2021/664. The Drone5GID is capable of providing the Remote ID of a UAS to the national Common Information Service Provider using LTE for Machine Type Communication (LTE-M) technology. A custom protocol, based on the ASTM F311-19 standard, has been implemented between the DroneID5G and a USSP prototype for reducing the message size being transmitted. Additionally, Detect And Avoid (DAA) capabilities have been implemented by relaying air traffic data, obtained from the Traffic Information service specified in 2021/664, into a UAS's flight controller via the DroneID5G.We present the initial experimental results, consisting of both ground and flight measurements, for investigating the performance and reliability of LTE-M network. The RSSI, RSRP, and RSRQ values have been collected at different geographical positions and altitudes from 20 to 100 meters above the ground. The ground measurements demonstrate the handover capabilities and reliability. From the flight measurements, it can be seen that the RSRP and RSRQ values decreases in relation to the altitude. Finally, the DAA capabilities are demonstrated, enabling the UAS to automatically detect an incoming aircraft and activate its failsafe.