MediaTek Brings Practical Satellite Communications To Mobile Devices

The most exciting recent innovation in mobile technology is satellite communications. Over the past six months, several smartphone OEMs, chipset providers, and wireless carriers have announced new developments for linking phones to satellites for emergency communications. Now MediaTek, the largest smartphone chipset provider by volume, has joined the movement and announced a new chipset to bring this capability to its customer base.

Satellite communications in mobile devices is being driven by standards released by the 3GPP. In the 5G Release 17, which was just frozen last fall, the standard outlines two forms of satellite communications referred to collectively as non-terrestrial networks or NTN. The first form is IoT-NTN, which will provide low data-rate narrow band (200KHz) communications. Not only will this be used for sending machine/IoT communications, but it will enable text messages, like that being touted by many of the prior satellite communications announcements. The second form is NR-NTN, which will provide broadband (5-20MHz) communications for high data-rate communications, such as video calls.

Just prior to Mobile World Congress (MWC), MediaTek announced the MT6825, a discrete chipset to enable two-way, text-based satellite communication. In accordance with the IoT-NTN standard, the MT6825 supports kilobit data rates on the L-band (1-2GHz) and S-band (2-4GHz) frequencies with a bandwidth of 200KHz. For comparison, this bit rate is similar to what you would have expected with 2G communications back when the primary purpose of a mobile phone was to make phone calls.

The MT6825 is a very small (5.6mm x 5.6mm) integrated chipset that includes an Arm Cortex-M4 CPU, 4MB of Flash and Pseudo-Static RAM memory, the transceiver, and power and clock management. Additional components will also be required for the RF front-end from other vendors. The MediaTek MT6825 platform supports the open 3GPP Release 17 IoT-NTN standard. This means once a device using the MediaTek platform has been certified for the standard, it can be used on any IoT-NTN compliant network.

What is unique about the MediaTek solution is that it will launch using geostationary orbit (GEO) satellites rather than the low-earth orbit (LEO) satellites that most of the other platforms are leveraging today. When using MediaTek’s 3GPP NTN solution, aiming will not be required, receiving messages should be as automatic as connecting to a cellular network, and the use of a proprietary satellite network is not required. MediaTek did indicate, however, that LEO satellites could be supported in the future.

As announced at CES, the first products launching with the MediaTek MT6825 chipset will be Motorola’s Defy series of smartphones coming out this quarter with support from the Bullitt Satellite Connect messaging service from the Bullitt Group.

Even with the limited IoT-NTN data rates, MediaTek envisions that this service will be used for more than just emergency SOS messages. MediaTek believes that it can be used practically for two-way text messaging, weather updates, and location tracking and sharing. MediaTek will demonstrate the platform at MWC in Barcelona next week with the promise of a video call over satellite, which is impressive.

Additional NTN specification enhancements will be supported in 3GPP Release 18, due to be finalized in 2024. However, the race to support satellite communications has already begun and will continue through new chipsets, new devices, new services, and most importantly, new satellites that will be launching over the next few years. By the end of the decade, Tirias Research believes that satellite communications/NTNs will become yet another link seamlessly integrated into wireless communications through carrier aggregation adding to the collective capacity and bandwidth resources of a given network. Some mobile network operators will partner with satellite operators to offer the satellite service, while others will establish their own satellite networks that support the NTN standards.

For many, satellite communication is not that interesting, especially if they live in a city with ubiquitous 5G coverage. But satellite communication has the potential to not only provide service in areas that lack reliable cellular coverage, it has the potential to enable a global infrastructure for industries like transportation that require service anywhere and to overcome the digital divide between regions and consumers by providing ubiquitous broadband service. Look for more on this topic in my next post.