Challenges of 3D Wireless Network Design and Management

This report encapsulates the challenges and considerations involved in designing and managing communication networks for aerial use cases. Key objectives include achieving high data rates, minimal latency, robust reliability, and integrating advanced sensing capabilities into the network fabric. This holistic approach aligns with the overarching goal of the 6G-SKY project: to pave the way for a technologically advanced and sustainable future in communication networks for aerial scenarios.
The document explores various communication architecture solutions, including mesh networks and device-to-device (D2D) coordination links. It also examines centralized versus distributed control architectures, highlighting a range of strategic possibilities to meet the complex requirements of individual use cases. A standout theme within this document is the integration of sensing capabilities with communication networks. This fusion enhances communication nodes with sensing abilities, creating an infrastructure primed for distributed data processing. Such integration has the potential to revolutionize the network's effectiveness, particularly in use cases that require sophisticated sensing capabilities.

First draft of NTN architectures with focus on commercial airplanes, HAPS, HIBS, and satellites

The main focus of this report is on connectivity between non-terrestrial (NTN) nodes, specifically for planes, unmanned aerial vehicles (UAVs), high-altitude platforms (HAPS), and satellites.
To achieve this, we will identify architectural issues, requirements, and options for medium to high altitude. Synergies towards smart cities, Industry 4.0, as well as the ongoing digitalization of society and public safety will be explored from an architectural viewpoint. The impact of HEXA-X 6G technology enablers, such as trustworthiness, connecting intelligence, network of networks, global service coverage, and extreme experience, will be examined with a focus on NTN.

Safety and Security

This report addresses the critical imperative of ensuring both security and safety in the context of the combined Airspace and Non-Terrestrial Network (ASN) concept proposed by the 6G-SKY project within the broader landscape of 6G technology. It begins by highlighting the unique challenges posed by the cyber-physical nature of 6G-connected aerial vehicles, emphasizing the potential direct impact of cybersecurity threats on safety, including human lives.

In response to these challenges, the report advocates for a comprehensive approach that goes beyond traditional security attributes to address the specific requirements of the combined ASN architecture. It underscores the importance of considering spoofing as a prominent security threat targeting unauthenticated communication protocols, which could compromise critical functionalities like advanced localization and drone detection.

Multi-Technology Connectivity Links: A2A, A2G, NTN HAPs, and NTN Satellite Links for 6G

This deliverable provides analysis of selected 6G links for air-to-air (A2A), air-to-ground (A2G), high altitude platform stations (HAPS), and non-terrestrial networks (NTN) satellite link communications. This report includes analysis of NTN satellite links from low earth orbit (LEO), medium earth orbit (MEO) and geostationary earth orbit (GEO) satellites serving as HAPS backhaul link. Analysis of links from HAPS to ground users focuses on providing coverage on rural areas, while analysis of A2G links between terrestrial base station and airborne users focuses on personal aerial vehicles and unmanned aerial vehicles (UAVs). A2A links are analyzed on the context of multi-technology links to serve UAVs. This report also analyzes free-space optics for use in Inter Satellite Links (ISL), Inter HAPS Links, links between satellites and HAPS and orbit-to-ground links (also called Direct To Earth (DTE)).

Final Report on NTN System Level Simulations

The final report on “NTN System Level Simulations“ provides a comprehensive summary of the evaluation work conducted on the coexistence of terrestrial and non-terrestrial gNBs within the NTN System Level Simulator. Scenarios featuring flying gNBs at varying altitudes, as well as mobile users situated on the ground or in the air, were defined for this purpose. The necessary parameter configurations for initializing these scenarios—including satellite payload, user terminal, channel model, and traffic model properties—were established. The report also includes a list of key performance indicators, such as SNR and throughput, which are utilized to analyze the evaluated scenarios based on specific parameter configurations.

Furthermore, the report outlines the handover process between two non-terrestrial gNBs and highlights other features that will be developed throughout the project. The role of artificial intelligence (AI) in a 6G system is also explored in this context.

Combined Airspace and NTN Networks: Use Cases, Scenarios, and Regulations

This report is intended for those readers that have an interest to get an overall view and understanding of combined Airspace and NTN networks (combined ASN networks).

The main benefits are that the Combined Airspace and NTN use cases, scenarios and regulations provide an overall framework of descriptions and analysis for combined ASN networks including a definition of holistic aerial networks, an identification and analysis of international programs for Innovating the Digital European Airspace and beyond, 6G regulations and spectrum for combined ASN networks, 6G use case segments for digital airspace and NTN, highlighted 6G-SKY use cases, 6G-SKY demo use cases, and a combined ASN networks impact on sustainability. This material can be further used to trigger research investigations and commercial actions for the readers of this report.

Holistic Adaptive Combined Airspace and NTN networks Architecture for 6G

This report aims to provide the reader with the initial design considerations of architectures for the combined airspace and NTN networks (combined ASN networks) with a focus on low altitude aerial platforms including airplanes as users.

This project report first discusses the primary principles for the design of combined ASN network architectures. These principles for the holistic adaptive 6G-SKY network architecture require new functional views to assure three-dimensional (3D) service requirements via network functions such as 3D end-to-end (E2E) and domain-oriented network orchestration and slicing. Other dimensions shaping the 6G-SKY network architecture are the EU aviation strategy with EU Single European Sky (SES) and Single European Sky ATM Research (SESAR) initiatives and requirements from urban air mobility and advanced air mobility. The report discusses design aspects of the ASN architecture to enable efficient network management and control of the multi-layered architecture.