First Voice over Narrowband NTN testbed demo at MWC 2025

At the upcoming Mobile World Congress 2025, Murata and Rohde & Schwarz are set to unveil a groundbreaking collaboration in the form of the first testbed for Voice over Narrowband Non-Terrestrial Network (NB-NTN). This innovative technology is designed to bring voice communication to remote and bandwidth-constrained areas where traditional terrestrial network access is limited or unreliable.

The introduction of NB-NTN technology represents a significant advancement in 3GPP-based satellite connectivity. By setting a new standard for satellite-based communications, this demonstration opens up possibilities for voice capabilities even in the most challenging and bandwidth-constrained environments.

The testbed itself is a product of cutting-edge technology, utilizing the CMW500 wideband radio communication tester from Rohde & Schwarz as a GEO/GSO satellite eNB emulator, in conjunction with Murata's Type1SC Cat.M1/NB-IoT/NB-NTN module featuring Sony’s Altair Chip ALT1250. Additionally, a VoIP client application developed by Rohde & Schwarz is employed, utilizing codecs that operate at ultra-low bitrates to address critical communication needs in scenarios where traditional networks fall short.

One of the key advantages of the ALT1250 modem is its ultra-low power consumption, which not only extends battery life significantly but also reduces maintenance costs. The chip's advanced power management capabilities enable IoT devices to operate for extended periods, ranging from weeks for smart wearables to over a decade for smart meters. Furthermore, the high level of integration and minimal external components required allow for module sizes as small as 100mm².

The rapid adoption of NB-NTN chipsets in various devices such as smartphones, wearables, and automotive systems is a testament to the technology's potential in enhancing ubiquitous connectivity. The demonstration showcases the versatility of Narrowband NTN services, offering push-to-talk voice capabilities alongside emergency SOS and SMS functionalities. This push-to-talk-like application is poised to enhance safety and communication capabilities in areas where terrestrial network access is limited or unavailable.