Iridium Communications and Deutsche Telekom IoT (DT IoT) have claimed the successful transmission of a voice message over the Iridium NTN Direct platform, in what is said to be a milestone demonstration with Toyota.
The first message sent – “testing, testing, one, two, freeway” – demonstrated standards-based NB-IoT voice messaging over Iridium’s fully operational low Earth orbit (LEO) satellite constellation, and was supported by Fraunhofer’s AI-based NESC voice codec.
The message was sent from a Toyota vehicle equipped with a Nordic Semiconductor nRF9151 development board, a Deutsche Telekom IoT SIM and transmitted entirely via the Iridium satellite network, following the successful completion of technical integration and a global roaming agreement between Iridium and Deutsche Telekom IoT.
Such a capability is seen as being able to extend reliable connectivity beyond terrestrial coverage for automotive, logistics, remote utilities, smart agriculture, emergency response and other internet of things (IoT) applications that need to stay connected wherever they operate. Through NTN Direct, the partners say eligible DT IoT customers using compatible standards-based NB-IoT devices will be able to roam between terrestrial networks and Iridium satellites.
Compred with regional satellite services that rely on cellular spectrum or are limited by geographic availability, Iridium NTN Direct is designed to extend coverage using Iridium’s existing global L-band LEO satellite constellation. The service uses an existing worldwide network, providing a path for mobile network operators, chipset manufacturers and device makers to extend connectivity without building or maintaining additional terrestrial infrastructure.
For Deutsche Telekom IoT, the integration is regarded as further strengthening its “network of networks” approach: combining terrestrial and non-terrestrial connectivity to provide customers with reliable IoT coverage wherever their assets operate.
With a roaming agreement now completed, Deutsche Telekom IoT customers can gain access to Iridium NTN Direct in Q4 2026 when commercial availability commences. In addition, selected European customers are already testing and developing applications on the Iridium network using Deutsche Telekom’s Global SIM.
Commenting on the test and potential service implications, Christian Schwalbe, CEO of Deutsche Telekom IoT, said: “Together with strong partners such as Iridium and many others, we are connecting mobile communications and satellite to form a global IoT infrastructure that keeps vehicles, machines and people reliably accessible. The demonstration with Toyota shows how technological innovation can be turned into concrete added value for our customers.”
Manfred Lutzky, head of the communications audio department at Fraunhofer IIS, added: “We are very pleased to support this automotive NTN voice proof of concept by providing Fraunhofer’s … AI-based NESC voice codec. NESC enables reliable, natural sounding and highly intelligible satellite voice services at scale by operating at bitrates of 1 kbps or less. This demonstration is a great example of cross-industry collaboration that will help to grow the satellite voice ecosystem.”
Iridium CEO Matt Desch said: “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. This demonstration is a glimpse into the future of truly global, standards-based connectivity.”
