Regulators will play a vital role in enabling D2D, but many are playing catch up. Authorisation regimes will need to prioritise licensing as well as spectrum and interference management if these new services are to finally help close the digital divide.
Satellite has become a focus for policymakers, with motivations from improving coverage to promoting investment. While Ofcom in the UK has become the first European NRA to propose rules for authorising D2D in mobile bands, Australia, Canada and the US have already established frameworks or guidance to support the technology's development.
Despite the current lack of ITU support for D2D mobile, comparable regimes are emerging, with the US a source of inspiration for other countries. As operators’ spectrum licences tend not to authorise connectivity via space, approvals are typically needed to test and launch services, with Australia a rare case of where permissions are not required.
Interference between terrestrial and satellite infrastructure is a priority issue that will need mitigation, particularly if countries authorise D2D mobile ahead of WRC-27. Regulators expect licensees to prevent harmful interference for other spectrum users, while warning that they should not expect to be protected from interference themselves.
Access to sufficient suitable spectrum is a major challenge for D2D services, with the technology increasing demands on a finite resource. Regulators are enabling D2D mobile in a range of frequencies, usually on a national basis, although the exact bands vary by region.
D2D authorisation regimes have so far not imposed obligations on providers to enable national roaming, although in Canada there is an intention to revisit this matter within the next five years. Similarly, regulators have not introduced measures to support D2D using HAPs, but in the UK, Ofcom is willing to reconsider this position if evidence of market demand comes to light.
D2D services are not new, but partnerships between telecoms operators and satellite providers are driving a new phase of growth
Commercial launches of non-geostationary orbit (NGSO) satellites – particularly those in low earth orbit (LEO) by companies such as Elon Musk’s SpaceX – have fuelled hype around the sector and how space-based communications might complement terrestrial telecoms networks to improve geographic coverage, choice and/or resilience, especially where it may be uneconomic or impossible to build a mobile tower. As optimism has grown, satellite-to-cellular connectivity – commonly referred to as direct-to-device (D2D) – has rapidly become the locus of attention. D2D is not itself new as technology enabling direct communications between a satellite and a specialist (and often expensive) phone has existed for some time. That said, the kind of D2D currently on many people’s radars enables connectivity to unmodified mass market handsets, and already has support from leading smartphone vendors including Apple. D2D services can be sub-divided into two categories:
D2D that leverages spectrum licensed to mobile operators (this may be referred to as D2D mobile or D2D in mobile bands); and
D2D that uses mobile satellite services (MSS) spectrum – also known as D2D MSS.
D2D is projected to be a multi-billion pound revenue opportunity, which the telecoms industry is actively seeking to tap into, striking partnerships with, or investing in, a host of satellite players. In the US, T-Mobile has partnered with SpaceX’s Starlink to launch a global space-based 4G and 5G mobile network. Using T-Mobile’s spectrum and Starlink’s satellites, this agreement aims to ensure “no more cell phone dead zones“ for T-Mobile customers. Vodafone is also keen to be at the forefront of this new battleground, having announced plans for the first commercial D2D service in Europe in 2025 and the creation of a European wholesale satellite service business with AST SpaceMobile. While D2D was in its infancy just a few years ago, it is maturing quickly, with additional operators – e.g. Entel, Kyivstar and Salt – working alongside satellite providers to in-fill networks and deliver broadband to hard to reach areas.
Regulators see the potential of D2D to enhance coverage and resilience, with the US positioning itself at the forefront
Policymakers are also keen to capitalise on the convergence of technologies to provide citizens with the best connectivity possible. In Sweden, the Post and Telecom Authority (PTS) has long been a supporter of satellite, considering it the “the only realistic alternative” to deliver connectivity across sparsely populated rural communities, including to meet broadband coverage targets set by the Government. In 2025, the PTS will introduce a new theme in its Technical Forum on Spectrum Usage Needs in order to understand the industry's spectrum requirements for D2D services over the next five to 15 years, as well as whether regulation must change to enable an effective service offering.
In the UK, Ofcom considers the potential benefit of D2D may be limited compared to countries with large areas of low population density where coverage can be poor. As with other relatively densely populated countries in Europe, the addressable market may represent just a fraction of the population. However, Ofcom still sees upsides for consumers living in or visiting rural areas or using coastal waters, and considers that its proposals would support growth in the UK by enabling innovative new services and that they would make it easier for operators to roll out mobile infrastructure. Canada’s federal institution that leads its Innovation, Science and Economic Development (ISED) portfolio considers that D2D mobile could help close coverage gaps, including along roads and motorways, with its policy objectives in this area also centred on promoting competition and investment, and supporting the increased reliability and resiliency of telecoms services. Notably, the US has not only pitched D2D as a way of expanding the reach of telecoms services, including emergency services, but also as a means of ensuring efficient spectrum management and securing leadership in cutting-edge, space-based technologies.
Developing successful D2D mobile services will depend on ensuring access to operator’s licensed spectrum, mitigating interference and overcoming performance challenges
Despite rising confidence in the promise of D2D services to close persistent digital divides, there are barriers to the further growth of the technology and ultimately the rate of end user adoption, which also present new challenges for policymakers. In addition to the need to introduce new handsets or adapt existing ones to enable these services, D2D MSS requires access to a dedicated supply of spectrum (e.g. in the L- and potentially the Ka- and Ku-bands) – a likely motivation behind the AST Space Mobile/Ligado Networks deal. Apple has a ‘walled garden’ proprietary solution with sole access to Globalstar's MSS spectrum in order to deliver emergency communications via iPhones, while Google has an agreement with intermediary provider Skylo to support its Pixel smartphones, driving competition among OEMs in this space. Similarly, securing appropriate terrestrial spectrum could be a challenge in the context of D2D mobile, with operators possibly reluctant to surrender valuable and finite resources used for traditional mobile broadband and divert them to fledgling satellite services, which could prompt regulators to consider mandating some sort of leasing or sharing model.
With the arrival of D2D mobile, there is a heightened chance of interference between satellites and mobile operators’ ground-based infrastructure. As such, one operator’s use of satellite should not degrade the performance of an adjacent terrestrial mobile network. There is also the risk of interference between countries, which has led to a push from some governments for satellite providers to set up monitoring zones near international borders, not route data through gateways or prevent unauthorised movement of end user terminals geolocation-based restrictions. D2D MSS avoids mobile operator interference by using dedicated satellite spectrum but as the Qualcomm/Iridium partnership showed, having the technological capabilities does not guarantee take-up by smartphone manufacturers.
Interference concerns are compounded by apprehension about quality of service given that it may take several minutes to send and receive messages via satellite, which only becomes more difficult as the consumer base rises. Although delivery times and capacity are expected to improve, D2D mobile will therefore be unlikely to be able to replicate the performance of 4G/5G networks, raising questions about whether operators will be able to effectively monetise the service and/or use it to meet regulatory obligations, such as coverage commitments. In New Zealand, the Commerce Commission filed criminal charges against One NZ, alleging its “unqualified” marketing misled consumers and distorted competition by overstating the coverage and performance customers could receive as a result of the operator’s partnership with SpaceX. Further, OneWeb’s 48-hour outage indicates that satellites may be as prone to failure as their terrestrial counterparts.
Operators’ spectrum licences traditionally do not authorise the transmission of telecoms services from space
A notable barrier in many countries is that operators have not yet been permitted to offer D2D mobile services using their existing spectrum holdings, indicating that regulation may need to be revised or introduced to reflect and facilitate technological advancements. In Australia, smartphones used in D2D mobile services can be provided under the current spectrum licensing framework without the need for explicit approval from the Australian Communications and Media Authority (ACMA). However, operators in Brazil, Canada, Chile, Japan, New Zealand, the UK and the US have required regulatory permissions and/or supervision to test (and in the case of New Zealand, launch) D2D services. As things stand, spectrum licences are typically defined for terrestrial usage only, the terms of which are set by the international Radio Regulations treaty maintained by the ITU. This still leaves room for D2D mobile services to be tested and launched within a country’s borders (with some technical limitations, including no protections from interference), suggesting that achieving universal coverage has more to do with a regulatory gap than a technological barrier. However, this issue will be a major agenda item at WRC-27, raising the possibility that regulatory obstacles could arise. Amid increasing pressure to accelerate approvals for pre-commercial trials, the choice for regulators is to wait until such services have been formally considered at the conference and to adopt the ITU's recommendations, or to develop a national authorisation model ahead of time.
Amid the outstanding questions and risks, certain regulators are taking steps to explore how to adapt existing regulations to accommodate and support this technology. The US, Australia and Canada have moved (in that order) to consult and establish frameworks or guidance for D2D, although One NZ has claimed the first commercial launch of D2D mobile services (albeit for texts only) in the world and KDDI in Japan completed a test of the technology in October 2024 following regulatory approval. In Brazil, Anatel has created a regulatory sandbox in the 850MHz band to enable operators to test D2D services until the end of 2025, while the UK is the first country in Europe to propose authorisations of the technology – see Figure 1.
An important milestone was reached in March 2024 when in the US, the Federal Communications Commission (FCC) adopted its Supplemental Coverage from Space (SCS) Framework, which came as a response to the development of telecoms-satellite partnerships. The framework – which the regulator considers will help deliver a “Single Network Future” – authorises mobile operators to extend coverage through cooperation with satellite providers using licensed, flexible use spectrum (if they respect the non-interference requirements). As discussed at MWC25, the US model is seen as a good starting point that has scope to iterate, as well as a useful reference for other countries. The FCC’s SCS regime was followed by ACMA’s regulatory guidance for operators of IMT satellite direct-to-mobile (i.e. D2D mobile) services and clearly influenced the thinking of Innovation, Science and Economic Development Canada (ISED) in its Decision on a Policy, Licensing and Technical Framework for Supplemental Mobile Coverage by Satellite (SMCS) – see Table 1.
However, other countries are at an earlier stage with licensing D2D, with some preparations complicated due to the scope for cross-border spectrum interference. The UK aside, Europe generally remains cautious due to high terrestrial coverage and spectrum congestion, as well as the presence of exclusion zones that reduce the ability of D2D to provide service in coverage gaps, including along national borders. While D2D mobile is arguably more suited island nations or countries with large landmasses, the EU’s Radio Spectrum Policy Group (RSPG) has consulted on a draft opinion on D2D and associated single market issues, which could be the first step towards a regime for supplemental coverage from space. However, delivering a regulatory framework based on international agreement of so many European countries will take time and therefore may only be completed close to WRC-27.
Providers of D2D services will be required to prevent interference but will face no protections themselves
Given the importance of mitigating interference, regulators have sought to tackle the issue in newly created D2D regimes – even excluding certain spectrum bands where the risk is greatest. In the US, one of the key objectives of the FCC’s SCS framework is to minimise the risk of harmful interference, both domestically and internationally, to existing terrestrial and satellite networks that support non-federal and federal users. The regulator has reminded licensees that SCS operations shall not cause harmful interference to other countries’ operations that conform to the ITU Radio Regulations and shall eliminate any harmful interference immediately, considering this provides a sufficient basis for moving forward with authorising D2D services. SpaceX requested a waiver on power limits for SCS in order to provide higher bandwidth levels, although stakeholders strongly objected, raising concerns about interference, and the FCC ultimately rejected the request.
In Canada, ISED noted concerns regarding the potential for interference from SMCS to existing licensees and the desire to ensure that SMCS does not impede current and future deployment of terrestrial networks by mobile operators holding existing spectrum licences. While retaining the view that potential interference could be mitigated through the adoption of appropriate coexistence measures and technical requirements, ISED (like the FCC) has has permitted the use of SMCS under a secondary allocation, and on a “no interference, no protection” basis (in light of the current absence of ITU recognition and provisions). In the UK, Ofcom has proposed that the conditions of any authorisation would require the operator(s) to manage the D2D network in a manner that does not cause harmful radio interference to existing spectrum users in the UK and overseas, and has outlined draft technical conditions for effective coexistence with terrestrial mobile networks and adjacent adjacent band spectrum users (e.g. in the 1400MHz and 2.6GHz bands). Notably, ACMA’s guidance appears fairly high level on the issue of interference, stating an expectation that spectrum licensees offering D2D mobile services should undertake their own due diligence to protect against interference, and that the regulator will closely monitor developments but may consider introducing specific coexistence requirements if necessary.
Authorisation of HAPs has so far been absent from D2D frameworks despite interest from operators
One type of infrastructure being explored to deliver those services is HAPs, which often reflect stratospheric drones or balloons. At MWC25, for example, Deutsche Telekom showcased an unmanned aerial vehicle (UAV) that would be operated as a flying mobile base station for temporary coverage. That said, HAPs have been markedly absent from the D2D regulatory frameworks implemented or proposed to date – and completely so from ACMA’s guidance and ISED’s decision. In the latest draft regime from Ofcom, decided not to develop any proposals that would authorise HAPs to D2D services. In its July 2024 call for inputs (CFI), the regulator did ask the question but received limited responses, suggesting limited interest in commercial deployment of HAPs in the short term. Ofcom stated, however, that it would welcome approaches from stakeholders as and when they are ready to offer services in the UK, and can review its position in the future, should evidence of demand arise. Similarly, some stakeholders suggested in response to the FCC’s notice of proposed rulemaking (NPRM) that the regulator accept applications for SCS from non-satellite, non-terrestrial service platforms, such as HAPS. However, the FCC stated that the draft framework did not make proposals regarding, or seek comment on, the issue of satellite services to airborne devices, with its final decision finding no need to change tack. That is not to say that HAPs are not of interest in this context and are being explored by NTT Docomo and SoftBank in Japan as a means of delivering 4G and/or 5G connectivity.
Regulators are making a range of spectrum bands available for D2D mobile, although they currently vary by region
Within authorisation frameworks for D2D mobile, regulators are outlining the licensed spectrum bands that may be used for these new services, typically on a national basis – see Table 2. In the US, the FCC’s SCS framework requires satellite operators to have a spectrum lease agreement with their terrestrial partner and existing satellite licensing under Part 25 of the FCC’s rules. The regime authorises flexible use in the 600MHz, 700MHz, 800MHz and 1900MHz bands. Understandably, in Canada, ISED’s SMCS model applies initially to a number of the same bands, while also requiring a non-exclusive agreement between a mobile operator and a satellite provider. While it is currently unclear from the agreements which spectrum bands will be used for Starlink’s operator partnerships in Japan and Switzerland, it has been reported that its global operations will use spectrum in the 1429-2690MHz range. In the US, it was announced the Starlink’s LEO satellites would use the 1900MHz, or n25, band, specifically 1910-1915MHz (for Earth to space communications) and 1990-1995MHz (for space to Earth). In Australia and the UK, regulatory frameworks either allow or could allow spectrum at 2.6GHz to also be used for D2D mobile services, with this band originally licensed for 4G services but now used for 5G as well.
National roaming obligations are not yet a feature of D2D regimes, but this is likely to change as the technology matures
Given the existence of national roaming obligations in some countries, there have been debates around whether an operator’s use of D2D technology should be covered by these requirements, which has in turn presented an issue on which there may be scope for an eventual divergence between different regulatory regimes. In the US, the FCC requested views from stakeholders on whether there are public interest reasons that Part 25 satellite provider lessees should be required to comply with any other service rules applicable to their terrestrial service partners, including roaming rules. The regulator ultimately declined to apply roaming requirements to SCS at this time, considering doing so would be premature and may introduce complexity and additional technical considerations that could affect the technology’s development, while also citing its tendency not to intervene in commercial agreements. In Canada, ISED consulted on two options for applying mandatory roaming to SMCS but came to similar conclusions than the FCC that imposing such an obligation now could stifle the development and deployment of D2D. It sided with the majority of stakeholders and will revisit a possible mandatory roaming requirement for SMCS licences in the future (i.e. 3-5 years).
In the UK, the issue of roaming was not included in Ofcom’s CFI nor in its November 2024 statement, indicating that it was not a major focus of stakeholder comments. However, the March 2025 consultation, Ofcom stated that it recognised the potential for D2D to extend emergency services access across the UK, and that it would engage with mobile operators and prospective satellite providers on this theme. Similarly, ISED has stated that it will revisit the applicability of network resilience and reliability requirements to SMCS as the technology matures and determine when the Memorandum of Understanding (MOU) on Telecommunications Reliability obligations for emergency roaming would be applied to SMCS. Elsewhere, Ghana’s Satellite Licensing Framework – though not focused predominantly on D2D – states that the trial or commercial deployment of direct connectivity between space stations and mobile devices must be received regulatory approval and be undertaken through the provider of the Rural Telephony Network (RuraCom), which has existing roaming agreements with the country’s mobile operators.
