But through a unique collaborative research and development effort between industry and academia, that may change, and regular mobile phones could soon be able to achieve connectivity in those kinds of areas.
The international research team from Singapore University of Technology and Design (SUTD), SKY Perfect JSAT (JSAT), TMY Technology (TMYTEK), Rohde & Schwarz, and VIAVI Solutions have developed a new 5G non-terrestrial network (NTN) satellite technology to advance mobile connectivity in remote locations.
The research team conducted a live demonstration at the World Expo 2025 Singapore Pavilion in Osaka, Japan, showcasing the deployment of an end-to-end cross-country 5G new radio (NR) NTN.
The demonstration showed a 5G signal transmitted from an end user equipment (UE), such as a communication device, located in Singapore via a satellite antenna, to a geostationary (GEO) satellite operated by JSAT. This signal was then forwarded from the satellite to a ground station in JSAT, Japan, which connects to a 5G base station and 5G core network emulator, demonstrating the feasibility of communications between NTN and terrestrial networks (TN). This is the first such transmission between the two countries.
The demonstration showed that an existing GEO satellite can reliably support the 5G NR standards as defined by the Third Generation Partnership Project (3GPP), which is a consortium that develops global standards for mobile telecommunications.
Although current 5G deployments primarily rely on TN, upcoming 6G networks are expected to be a convergence of both TN and NTN to achieve global coverage and resilient connectivity. This demonstration will help to lay the foundation for future extensions to medium earth orbit (MEO) and low earth orbit (LEO) satellites, as well as 6G converged TN and NTN.
Commenting Professor Tony Quek, Director of Singapore’s Future Communications R&D Programme (FCP) and the Head of SUTD’s Information Systems Technology and Design pillar said, “As host of the Singapore’s National Future Communications R&D Programme (FCP) and its Future Communications and Connectivity Lab (FCCLab), SUTD is proud to bring together partners JSAT, TMYTEK, Rohde & Schwarz, and VIAVI to collaborate and push the boundaries of 5G technology. Each one brought a different expertise to the research effort and together, we were able to achieve this breakthrough.”
This joint collaboration is also among the first in the world to integrate an electronically steered antenna (ESA) for 5G NTN GEO communications which enables NTN technology to be more suitable for challenging use cases, such as in the maritime and autonomous vehicles industries; or connecting 5G UE to high-speed moving satellites such as LEO or MEO.
Satellite operators, mobile network operators, equipment vendors and end-user application providers need to be able to evaluate the performance of NTN networks and the traffic that runs across them, so Rohde & Schwarz and VIAVI have developed an NTN digital twin testbed covering LEO, MEO and GEO, and this was used in the testing and validation of the end-to-end connectivity and performance in the live demonstration.
“This breakthrough in 5G NTN technology marks a pivotal moment - not only proving that seamless mobile communication over satellite is achievable, but also laying the groundwork for resilient, borderless 6G networks,” added Said Dr Sameh Yamany, Chief Technology Officer of VIAVI Solutions.
