Publications Conference paper · Mega-constellations · 2026

RF-Emulated TN-NTN Testbed for Service Continuity in Emergency Communications

Arnau Singla, Roger Pueyo Centelles, Anna Calveras, Juan A. Fraire, and Joan A. Ruiz-de-Azua

Joint European Conference on Networks and Communications and 6G Summit (EuCNC/6G Summit), pp. 1308–1315, 2026

Abstract

The integration of non-terrestrial networks (NTN) with terrestrial infrastructure is fundamental to the sixth generation (6 G) vision of ubiquitous connectivity. However, validating hybrid terrestrial-NTN systems requires realistic testbeds that capture radio frequency (RF) propagation effects and timing synchronization challenges beyond IP-level simulation capabilities. This paper presents a federated RF-emulated testbed for integrated network validation, using OpenAirInterface (OAI) 5G NR, software-defined radios, and both custom open-source (GNU Radio) and commercial (Keysight PROPSIM) channel emulators. The geographically distributed architecture spans i2CAT Foundation and Gradiant research centers, enabling collaborative experimentation. We implement and validate two application layer handover mechanisms for an emergency response use case in which a rescue vehicle transitions between terrestrial and geostationary satellite coverage. Experimental results demonstrate that our GNU Radio achieves partial 5G NR attach while PROPSIM enables complete attach with bidirectional data transfer, identifying timing synchronization as the critical technical challenge. Results achieve handover success with complete service continuity, confirming that position reporting services successfully operate with GEO satellite latency. This work provides a reference implementation and validation methodology for the NTN research community using OAI, demonstrating the feasibility of integrated terrestrial satellite systems for emergency communications.

Cite

DOI 10.1109/eucnc/6gsummit68295.2026.11577622

BibTeX

@inproceedings{singla2026rfemulated,
  author    = {Singla, Arnau and Pueyo Centelles, Roger and Calveras, Anna and Fraire, Juan A. and Ruiz-de-Azua, Joan A.},
  title     = {{RF}-Emulated {TN-NTN} Testbed for Service Continuity in Emergency Communications},
  booktitle = {Joint European Conference on Networks and Communications and 6G Summit (EuCNC/6G Summit)},
  pages     = {1308--1315},
  year      = {2026},
  doi       = {10.1109/eucnc/6gsummit68295.2026.11577622}
}

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