Fraunhofer IIS and Viasat, Inc. demonstrating a bi-directional voice call over Viasat’s geostationary earth orbit (GEO) satellite.
At the 5GAA members meeting in Sacramento, CA, Fraunhofer IIS, developer of the AI-based NESC voice codec, and Viasat, Inc., a global leader in satellite communications, have taken the next step in NTN D2D connectivity by demonstrating a bi-directional voice call over Viasat’s geostationary earth orbit (GEO) satellite.
The 5G Automotive Association (5GAA) is a global, cross-industry organization of companies from the automotive, technology, and telecommunications industries (ICT), working together to develop end-to-end solutions for future mobility and transportation services. Viasat and Fraunhofer are members of 5GAA and used the opportunity of the meeting to let the automotive industry participants experience first-hand what in-vehicle calls and concierge services will sound like using Fraunhofer IIS’s best-in-class, AI-powered ultra-low bitrate voice codec NESC.
NESC ensures optimal voice quality at scale and even under the most constrained satellite bandwidth conditions. While current speech codecs work well for terrestrial 4G/5G voice services, they typically require 13 kbit/s or more to achieve good audio quality – a fact which makes them ill-suited or impractical for large-scale applications such as NTN voice services. Fraunhofer NESC, reduces the required bitrates to 1 kbit/s or less and therefore can help to shape the future of satellite voice services.
“We very much appreciate the opportunity that 5GAA has given us, to demonstrate to Mobile Network Operators (MNOs) and the Automotive Industry, the feasibility, quality and real-world use cases that Fraunhofer NESC enables over satellite,” says Manfred Lutzky, Head of the Communications Audio Department at Fraunhofer IIS. “In collaboration with Viasat we managed to achieve bi-directional voice call quality comparable to that of terrestrial phone calls, at 10% of the bitrate used by legacy speech codecs.”
“Viasat’s membership in the 5GAA underscores our commitment to advancing the future of connected mobility through resilient, satellite‑based connectivity solutions,” said Kevin Cohen, VP, Strategic Partnerships & Business Development. “By integrating Fraunhofer’s NESC codec, we are able to deliver enhanced voice call quality at significantly reduced bitrates—ensuring reliable performance even in the most remote and bandwidth‑challenged satellite environments.”
“The Sacramento demonstrations represent an important milestone for connected mobility in the United States”, said 5GAA Chairman Christoph Voigt. “Seeing these technologies in action underscores how our members are delivering practical, interoperable solutions that enhance safety, connectivity and mobility for drivers and communities”.
Fraunhofer, booth #CS64, and Viasat, booth #6A20 will also demonstrate NTN Voice with Fraunhofer NESC at the Mobile World Congress (MWC) 2026 in Barcelona (March 2-5).
NESC is a registered trademark of Fraunhofer in Germany, and other countries. Viasat, the Viasat logo and the Viasat signal are registered trademarks of Viasat, Inc.