Iridium and Deutsche Telekom Demonstrate Satellite Voice Messaging in Toyota Vehicle

Iridium Communications and Deutsche Telekom IoT successfully transmitted a voice message from a moving Toyota vehicle using satellite technology. This technical achievement supports the development of the Iridium NTN Direct service. The demonstration confirms that low-Earth orbit (LEO) satellite networks can provide connectivity in locations where terrestrial cellular coverage is unavailable.

"The voice message sent over our network from a Toyota vehicle illustrates how Iridium NTN Direct will enhance consumer and commercial applications for people and assets operating outside traditional coverage areas," said Matt Desch, CEO of Iridium, in a statement.

Technical Architecture of the Demonstration

The test used a Nordic Semiconductor nRF9151 development board and a Deutsche Telekom IoT SIM card to send the phrase "testing, testing, one, two, freeway." To manage the bandwidth constraints of satellite links, the partners integrated the Fraunhofer IIS NESC (Next-Generation Speech Codec) Voice Codec.

"NESC enables reliable, natural sounding and highly intelligible satellite voice services at scale by operating at bitrates of 1 kb/s or less," said Manfred Lutzky, Head of the Communications Audio Department at Fraunhofer IIS.

Commercial Roadmap and Availability

This demonstration verifies the technology, though the Iridium NTN Direct service remains in the testing phase. Commercial availability is scheduled for the fourth quarter of 2026. Selected European customers are currently testing applications for the network, which is designed to extend connectivity for consumers and industrial IoT assets.

"The future of connectivity does not end where terrestrial networks reach their limits," said Christian Schwalbe, CEO of Deutsche Telekom IoT.

Expanding Non-Terrestrial Networks

The project reflects the industry effort to integrate Non-Terrestrial Networks (NTN) into standard consumer hardware. By using existing chipsets like the Nordic Semiconductor nRF9151, the partners aim to simplify the transition between terrestrial cellular towers and satellite constellations. This approach avoids the need for specialized satellite phones by allowing standard mobile-capable hardware to access global messaging services when traditional networks are unavailable.