Sat-IAB: Satellite and Integrated Access Backhaul (IAB) – An Architectural Trade-Off

Backhauling service has been a considerable market for satellite communication systems, particularly to support areas that are too expensive to reach or too difficult to deploy conventional terrestrial networks. Therefore, given the promising role of IAB in 5G networks, it is of great interest to analyze and evaluate the potential benefits that IAB can bring to the non-terrestrial domain and/or as enabler for integration of NTN into 5G networks. While IAB could possibly bring efficiencies in the area of spectrum re-use between user and backhaul links, these possible benefits need to be put into a satellite regulatory context. Therefore, this activity will identify promising IAB architectures in future satellite-terrestrial integrated communications networks, and select the most promising ones to be further investigated via SW-simulations.

The significant global increases in network traffic brings one major challenge, which is to substantially improve the underlying backhaul infrastructure. Considering the large available bandwidth in mmWave band, the cellular operators can consider different spectrum sharing scenarios for the Radio Access Network (RAN) and the backhauling network. This technique is known as integrated access and backhaul (IAB), and has recently attracted a lot of attention both from academia and stakeholders. The key concept of IAB is to reuse the existing framework of 5G access link for the backhaul as well, by efficiently multiplexing access and backhaul in the time, frequency and/or space domain.

In terrestrial 5G networks, the concept of IAB is nowadays being standardised and initial deployments of IAB are being experimented with. IAB will support very flexible network deployments by allowing RAN nodes (gNB’s) to function as a relay to other network nodes, in addition to acting as regular access node for user equipment. The application of IAB could potentially support future heterogeneous “3D” networks that consist of satellite, terrestrial, airborne and maritime nodes and still need standard mechanisms for resource management, service management and orchestration of the many links within such topologies.

Backhauling service has been a considerable market for satellite communication systems, particularly to support areas that are too expensive to reach or too difficult to deploy conventional terrestrial networks. Therefore, given the promising role of IAB in 5G networks, it is of great interest to analyze and evaluate the potential benefits that IAB can bring to the non-terrestrial domain and/or as enabler for integration of NTN into 5G networks. While IAB could possibly bring efficiencies in the area of spectrum re-use between user and backhaul links, these possible benefits need to be put into a satellite regulatory context. Therefore, this activity will identify promising IAB architectures in future satellite-terrestrial integrated communications networks, and select the most promising ones to be further investigated via SW-simulations.

Specifically, we will propose different IAB NTN architectures, considering different satellite orbits and orbit combinations, all relevant frequencies, all relevant UE classes (be it on ground or in space), FDD/TDD modes, out-of-band and in-band backhauling, and combinations of above for which the use of IAB could add value. A simulation campaign will be carried out to assess the potential benefits of the shortlisted architecture(s).

Funding: This project is funded by the European Space Agency (ESA)

Project Starting Date: July 2022

Project Duration: 6 Months

Research Team:

• Prof. Symeon Chatzinotas
• Dr. Steven Kisseleff
• Dr. Eva Lagunas
• Dr. Zaid Abdullah 

Contact: steven.kisseleff@uni.lu