Italian firm Celeste Technologies has completed a 5G NR-NTN interoperability test campaign at Qualcomm’s laboratories in Lannion, France, using Sateliot’s LEO direct-to-device (D2D) satellite constellation.

The joint campaign focused on 3GPP Release 17 NTN, validating end-to-end interoperability between Celeste’s SmartgNB and a mobile test device powered by a Qualcomm 5G modem-RF device.

Tests were executed using Celeste’s fully software-based SmartgNB running on a multi-core SoC, without hardware acceleration, combined with a Keysight Propsim channel emulator and a mobile test platform (MTP) from Qualcomm.

“This successful 5G NR-NTN interoperability test demonstrates the maturity of a standards-based, direct-to-device ecosystem,” said Francesco Grilli, vice president at Qualcomm (www.qualcomm.com). “Conducted in our Lannion labs with Celeste and Sateliot, it validates end‑to‑end performance and brings space‑based connectivity a step closer to commercial reality for IoT and D2D use cases across Europe.”

The trials covered GEO and LEO scenarios, both transparent and regenerative payload profiles, demonstrating that Celeste’s gNB can interoperate with Qualcomm’s NTN-capable device stack under realistic satellite conditions. The tests achieved end-to-end traffic between the SmartgNB and the MTP, validating complete protocol stack functionality. This activity took place within Sateliot’s broader initiative to develop a European LEO constellation for 5G NR-NTN D2D services in S-band.

SmartgNB is a software 3GPP Release 17-compliant gNB protocol stack for regenerative satellite payloads and on-board processing. It runs entirely in software from layer one to three, with CU/DU splits and platform independence across x86, Arm and Risc-V CPU architectures.

By demonstrating efficient operation on a SoC without hardware accelerators, the test campaign confirms the suitability of SmartgNB for integration into regenerative payloads and multi-operator LEO constellations.

Spanish firm Sateliot is deploying a LEO-based 5G NR-NTN payload in S-band, the corresponding space platform and the software ground segment, designed to provide reliable, continuous coverage and low-latency connectivity for IoT and D2D communications. This 5G NR-NTN constellation will complement Sateliot’s existing NB-IoT NTN service, adding capabilities tailored to automotive, civil security and defence use cases where 5G NR is the appropriate radio interface.

With an always-on, fully connected constellation including inter-satellite links and a proprietary ground-station network, Sateliot aims to be a key European player for discretionary services.

“This achievement is a key step in Sateliot’s roadmap to deliver a 5G NR-NTN constellation providing real-time, continuous coverage for IoT and D2D services, including demanding automotive, civil security and defence applications,” said Jaume Sanpera, CEO of Sateliot (sateliot.space). “By validating interoperability between Celeste’s SmartgNB and Qualcomm’s NTN platforms with our unique technology payload, we are strengthening Europe’s position in secure, sovereign, space-based connectivity.”

Celeste Technologies (celestetechnologies.com) has developed fully software-based, 3GPP-compliant NTN gNB products for regenerative satellites, offering software licensing, customisation and support for multi-operator 5G and future 6G constellations.