Presenting the world's first Voice over Narrowband NTN testbed

Murata and Rohde & Schwarz have developed the world's first Voice over Narrowband Non-Terrestrial Network (NB-NTN) testbed. To be presented at Mobile World Congress 2025, this innovative demonstration marks a notable leap in 3GPP-based satellite connectivity. The resulting push-to-talk-like application will improve safety and communication capabilities in areas without terrestrial network access.

Murata and Rohde & Schwarz have collaborated to present the world's first testbed for Voice over Narrowband Non-Terrestrial Network (NB-NTN), presented at Mobile World Congress 2025. With this demonstration, the two companies set a new standard for satellite-based communications, paving the way for voice capabilities even in the most bandwidth-constrained environments.

The innovative testbed uses the CMW500 wideband radio communication tester from Rohde & Schwarz as a GEO/GSO satellite eNB emulator, together with Murata's Type1SC Cat.M1/NB-IoT/NB-NTN module featuring Sony's Altair Chip ALT1250. It also utilises a VoIP client application developed by Rohde & Schwarz, which employs codecs that operate at ultra-low bitrates. This technology manages critical communication requirements where conventional networks are inadequate. The demonstrator opens the door for push-to-talk-like NB-NTN applications, especially suited to emergencies, disaster response, remote areas, and maritime operations.

With the rapid adoption of NB-NTN chipsets in smartphones, wearables, and automotive systems, this technology greatly enhances ubiquitous connectivity solutions. The demonstration highlights the potential of enhanced Narrowband NTN service with push-to-talk voice and emergency SOS and SMS. The partnership between the companies reflects their joint commitment to advancing NTN-related use cases.

Visit Murata at MWC 2025, booth 5D66, hall 5, to experience this milestone demonstration live.