The U.S. is facing a significant coincidence of interests in compelling initiatives for the reallocation of a share of the radio spectrum, specifically the 18.1 to 18.6 GHz band, towards commercial application in space communications. This initiative, encouraged jointly by the National Telecommunications and Information Administration (NTIA) and the National Aeronautics and Space Administration. is a potential tipping point in space infrastructure development and the interaction of government agencies with the growing commercial aerospace sector.
The genesis of this movement lies in the formation this year of a task force dedicated to the 18 GHz band. This joint task force sees the active participation of key players such as NASA, the Department of Defence (DOD) and the NTIA itself, reflecting the strategic relevance and complexity of the implications of such a reallocation. The primary objective of this working group is to carefully evaluate the need for a domestic allocation of the band in question to the Inter-Satellite Service (ISS), opening new frontiers for communication between satellites.
The core of the arguments in support of this reallocation lies in NASA’s changed requirements in terms of space-to-space links. The report produced by the working group highlights a crucial transition: NASA no longer plans to build additional tracking and data transmission satellites (TDRS), which have formed the backbone of its satellite communications infrastructure for decades. This decision imposes the need to find alternative, sustainable solutions to ensure the continuity of the inter-satellite data links that are essential for the agency’s future space missions.
The allocation of new frequencies to federal and non-federal entities in the 18 GHz band for inter-satellite service is a forward-looking initiative that can provide the necessary regulatory assurance to stimulate the development of commercial services that will be capable of meeting NASA’s future needs. This vision also aligns with the direction of the US Congress, which has been calling for NASA to make use of commercial space services as far as feasible while promoting the growth and innovation of the private space industry.
Useful for federal missions
The 18 GHz band, however, is not planned to be used to fulfil the needs of NASA alone. The working group’s report emphasises its potential use in support of other federal missions requiring inter-satellite links operating in the satellite Ka-band, further expanding the range of applications and benefits from this reallocation.
The working group’s proposal goes so far as to urge swift action by the Federal Communications Commission (FCC). The hope is that the FCC will issue a Notice of Proposed Rulemaking (NPRM) as soon as possible to define the allocations and service rules for the new use of the 18 GHz band for the ISS. Subsequently, an early adoption of a Report and Order is hoped for, formally sanctioning this reallocation and outlining the regulatory framework. The implications of such a decision are multiple and far-reaching. The availability of a dedicated band for commercial space-to-space communications could incentivise new players to enter the market, stimulating competition and innovation in the development of advanced satellite communication technologies and services. This could result in more efficient, flexible and potentially cheaper solutions for inter-satellite communication needs, benefiting not only NASA but also other government agencies and, eventually, the private sector.
Better communication services
The reallocation of the 18 GHz band can also encourage the development of novel satellite architectures and interconnected satellite constellations that can offer global communications services with increased resilience and capacity. The low latency, high data rate inter-satellite links provided by this band can significantly contribute to the performance of a wide range of applications, including Earth observation, scientific communications, satellite navigation, and even space exploration missions in the future.
Also, the redistribution of a portion of the radio spectrum is a complex task requiring a delicate balance of interests of all the parties involved. Today, the 18 GHz band can be used for other government and commercial purposes, and it will be necessary to ensure that the new allocation for space-to-space communications will not create harmful interference to existing services. The FCC’s rulemaking process will, therefore, have to weigh carefully the potential benefits of the new allocation against the need to protect existing spectrum uses.
The US initiative to free up the 18 GHz band for commercial space-to-space communications is a strategic initiative that may reshape the satellite communications ecosystem. The fact that NASA and NTIA are working together, with the support of the Department of Defence, is a testament to a recognition of the necessity to invest in advanced space communications infrastructure. The potential replacement of traditional TDRS systems with new commercial services and the opening of the band to other federal and, ultimately, commercial applications have the potential to trigger a virtuous circle of innovation and growth in the aerospace sector. The next critical step will be for the FCC to translate this vision into a concrete regulatory framework able to guide the development and deployment of this promising technology.
