This article is part of the Spectrum Policy Trends 2025 report. Download the full report for a handy compilation of the top five spectrum policy trends for 2025.
Direct-to-device (D2D) connectivity from satellite continues to attract attention from policymakers at a time when new LEO players are expanding capacity and established satellite players are assessing their relevance to the D2D space. Mobile operators remain enthusiastic about safely bringing a possible new technology into their access networks but remain cautious about interference and realistic about the limits of D2D’s use in expanding connectivity. D2D regulation is one area that requires definition, but it is not the only one.
Why is it important?
D2D has some strong potential use cases, but the exact nature of its importance is one of the issues that requires definition. 4% of the world’s population currently live outside mobile coverage, while 37% live within coverage but do not use it. D2D can potentially help address the 4% coverage gap but not the 37% usage gap.
For mobile network operators (MNOs), there are two broad use case categories in which D2D could be beneficial. Firstly, customers in some areas (typically higher-income countries) may be willing to pay more for connectivity outside populated areas, including outdoor enthusiasts or drivers on rural roads. Secondly, MNOs may be able to offer D2D services to provide basic coverage where base stations are not economically viable, allowing them to not only fulfil regulatory commitments but also offer new services such as agricultural IoT.
What are the policy considerations?
D2D may operate in mobile spectrum, on standard handsets, using the chipsets also used for terrestrial mobile (IMT), or on handsets that have chipsets to use the 3GPP satellite bands (e.g. n255/6 for L-band and S-band satellite D2D respectively).
D2D is already available using more complex handsets, such as recent iPhones or the Google Pixel 9, and mobile satellite spectrum. However, the chipsets used for this connectivity are not on cheaper phones and are unlikely to be affordable for many of the global population. D2D will operate in mobile satellite and in IMT spectrum, and the latter’s promise is that genuinely standard handsets can be used: simpler handsets will tend to come at a lower cost. Spectrum issues concerning D2D present substantial challenges. International and cross-border coordination will be critical for D2D’s operational sustainability. D2D will not be a benefit unless it can coexist safely alongside terrestrial mobile and other services. WRC-27 addresses each of those topics separately, and there are a lot of technical and regulatory aspects that need to be resolved.
Figure 1: WRC-27 spectrum discussions related to direct-to-device and mobile satellite
Note: The bands in the bold are already used for IMT.
What to expect in the year ahead
While there is much enthusiasm to continue driving the technology forward, it is also vital that governments that wish to introduce D2D before WRC-27 (and before the parameters and regulations for coexistence are agreed) should do so cautiously and with the primary goal of avoiding interference. At a national level, licensing mechanisms may require change – and new definitions for regulatory frameworks governing hybrid D2D services will need to be developed.
Consumers care about service quality – not the underlying technology – and so a cohesive regulatory framework that ensures coexistence between terrestrial and non-terrestrial networks is critical. It is paramount that D2D has a positive impact on mobile connectivity, and it must not cause interference into terrestrial networks. The US has already developed its first D2D regulations through the FCC (see below). The Australian telecoms regulator (ACMA) has also announced that IMT-based satellite direct-to-mobile services can operate under Australia-wide spectrum licences. Other regulators have sought industry input on satellite-based communication services, although others are waiting until ITU guidelines are developed through the WRC-27 cycle.
| Policy in practice: FCC adopts rules to facilitate the deployment of supplemental coverage from space (SCS) D2D policy development should be done cautiously – while a few governments have progressed in this area, they are large countries without significant cross-border interference issues. This new policy area will not have the technical details for proper governance until after WRC-27. The FCC has developed its regulations for D2D through its ‘supplementary coverage from space’ (SCS) regulation. D2D regulation development in the US was possible due to its continent-wide size (4,500km) and limited cross-border interference issues. The SCS regulation picked up two important issues regarding D2D in mobile bands: 1) D2D in IMT bands should be secondary. “SCS will be authorized pursuant to a secondary MSS allocation in the U.S. Table. These operations may not cause harmful interference to—and shall not claim protection from—any station operating in accordance with ITU provisions, whether in the United States or internationally.” 2) D2D in IMT bands should be delivered through the terrestrial licence holder. “We authorize SCS only where one or more terrestrial licensees … lease access to their spectrum rights to a participating satellite operator.” |