Spectrum Interference in the New World of Space and 5G


As a spectrum manager in the commercial communications satellite industry, one issue that of daily concern is spectrum interference. With the advent of what I call new dawn for space and terrestrial communications industry, this issue is an increasing challenge as new technology allow the greater exploitation of the spectrum environment. However, with these exciting opportunities, there is a greater likelihood of unacceptable spectrum interference. Nonetheless, working together, we can minimize this risk into our commercial satellites and other space-borne and terrestrial communications technologies, thereby bringing high-quality communications services to the United States and globally.

The satellite industry is heading in this exciting time. First, the digital universe is growing faster than at any time before. For example, when we look at 2013, the digital universe represented by the stack of memory in tablets would only reach two-thirds of the way to the moon. In 2020, we expect that stack to grow to 6.6 times to the moon. Further, in 2015 we had less than 5 Exabyte of global mobile traffic and in 2020 we estimate there will we more than 30 Exabyte of global mobile traffic — and that growth is not expected to slow down — especially with the advent of the roll-out of the 5G global network of networks early next decade.

It is not surprising then that when you look at the space environment, the use of spectrum by the commercial satellite industry’s growth is astounding. First, we expect demand for broadband services provided by Geostationary Orbit (GEO) satellite networks to increase exponentially with the greater demands for speed and capacity and greater need to bring services anywhere at any time. Today’s systems, including Hughes, are supporting Federal Communications Commission (FCC) -defined broadband speeds of 25/3 Mbps and more, with speeds of 100 Mbps and more expected in the early part of the next decade. The commercial satellite broadband industry today supports millions of subscribers worldwide and has invested tens of billions of dollars in its networks. These investments and subs keep increasing and their communications must be protected.

On the horizon, we are also seeing the deployment of networks of thousands of Non-Geostationary Orbit (NGSO) satellites that will bring advanced broadband and 5G services globally on a cost-effective basis, including to the polar regions and the oceans, which today have limited coverage. Other NGSO systems will provide a variety of services including weather monitoring, tracking, and the like. These systems are not just important for commercial services, but also are critical for other uses such as those of the U.S. military, national security, and public safety. And once again, the development of these systems is resulting in significant investment in infrastructure in the U.S. and globally. And because of these and other growing space demands, we have seen the development of a strong U.S. launch industry with new entrants such as SpaceX and Blue Origin and others on the horizons. In addition, we have been able to attract increasing satellite manufacturing capabilities, such as Airbus in Florida. As a satellite operator, I welcome these new players who bring increased competition into the satellite industry, as well as increased reliability and lower costs.

Each commercial satellite system will have its own individual demands for spectrum that are required to be met and are important for the United States and the world to meet needs for 5G communications. Of course, it is critical to ensure that these communications are protected from harmful interference.

When we look at the potential for harmful interference to commercial satellites, we must not limit our examination to looking up only –spaced based threats. An equally important area where we may face interference is from terrestrial technologies including 5G, as well as other non-terrestrial technologies, such as high-altitude platforms.

Now, the good news. We are starting with a very sound basis to protect commercial satellites from harmful interference. On the space side, between satellite systems, the International Telecommunications Union (an arm of the United Nations) has implemented an effective coordination process between satellite networks for spectrum (and also the use of the GEO). Under this process, satellite network operators engage in coordination to avoid harmful interference to one another and, because of this framework, are able to actively address interference concerns before launch and occurrences when they happen. Further, there are domestic and international rules that govern spectrum use that protect against the potential for harmful interference. These include the ITU Radio Regulations, which are updated every three to four 4 years at World Radiocommunication Conferences as well as domestic rules that countries, including the United States, have implemented that impose technical restrictions on operations to prevent unacceptable interference.

In addition, there is a fair amount of informal operator to operator communications to avoid harmful interference and address issues as they occur. Because of the need for all operators to avoid harmful interference, both the formal and informal approaches generally work well. The issue comes up if there are bad actors or folks who are simply uninformed about these processes; in this case, neither formal nor informal processes will work.

With the current focus on increasing awareness and need for a sustainable space environment, combined with increasing pressure on access to spectrum, the White House has announced several important policies that should advance interference protection. First, earlier this year, the President released Space Directive 3 (SD 3), which has the important goal of preventing unintentional Radio Frequency (RF) interference. In particular, SD3 recognizes that growing orbital congestion is increasing the risk to U.S. space assets from unintentional RF interference and that the United States should continue to improve policies, processes, and technologies for spectrum use (including allocations and licensing) to address these challenges and ensure appropriate spectrum use for current and future operations.

In addition, SD 3 tasks the U.S. government to verify consistency between policy and existing regulations regarding global access; investigate the advantages of addressing spectrum in conjunction with the development of STM systems, standards, and best practices; and promote flexible spectrum use; and investigate emerging technologies for potential use by space systems.

To this end, the Secretaries of Commerce and Transportation, in coordination with the Secretaries of State and Defense, the NASA administrator, and the director of national intelligence, and in consultation with the chairman of the FCC, are required coordinate to mitigate the risk of harmful interference and promptly address any harmful interference that may occur.

SD 3 has been complemented by the recent White House Spectrum Memo, which has a domestic focus and the goal of which is to increase spectrum access for all users, including on a shared basis, through the transparency of spectrum use and improved cooperation and collaboration between federal and non-federal spectrum stakeholders. In addition, it charges the government with creating flexible models for spectrum management; developing advanced technologies, innovative spectrum-utilization methods, and spectrum-sharing tools and techniques that increase spectrum access, efficiency, and effectiveness; building a secure, automated capability to facilitate assessments of spectrum use and expedite coordination of shared access among federal and non-federal spectrum stakeholders; and improving the global competitiveness of United States terrestrial and space-related industries and augment the mission capabilities of federal entities through spectrum policies, domestic regulations, and leadership in international forums.

So, how can we leverage these policies to improve the satellite industry’s protection from interference? Let’s start with the very basics. What does the commercial satellite industry need to be protected from harmful interference?

Our first building block is the one we rely on today. Use of the ITU coordination process, as well as the ITU radio regulations and domestic regulations which protect against interference. These regulations must be clear, transparent and not overly administratively burdensome as the White House policies recognize. However, SD 3 also recognizes that these processes must be improved. With an upcoming World Radio Conference this year important issues will be addressed on the large fleets of NGSO systems which are coming and how to better include them in the ITU coordination process. However, further action needs to be taken on a number of fronts, including for small satellites — especially as the operators may not be so sophisticated to understand existing processes.

In addition, domestic governments must address these challenges head-on. In the United States, the FCC has been actively addressing both issues and is in the process of revising its regimes to begin to address the very real issue of having new fleets of NGSOs and small satellites operating in the RF spectrum resource.

While work is underway both on international and domestic bases, I am concerned that we are not moving quickly enough. Unfortunately, there are certain administrative processes that must be followed to address these important spectrum issues. Accordingly, as discussed below, it is important for governments and the ITU to start to look at ways to enable flexibility in the appropriate regulations to enable innovation. In addition, informal processes can help fill the gap. This is an area that warrants further attention.

Additionally, international and domestic work to manage spectrum interference must continue to be complemented by an individual operator’s efforts at informal coordination. I am happy to report that several of our industry associations are actively looking at developing best practices to address these critical issues.

Moving on, the satellite industry also needs adequate access to spectrum with adequate interference protections contained in the regulatory regimes for all our uses — both gateways and user terminals; this means there are certain bands today where technology does not enable co-primary sharing between two ubiquitous services, such as 5G mobile terrestrial and satellite broadband to work on a non-interference basis. This means that interference from terrestrial systems and other non-terrestrial uses must be managed on both a domestic and international basis to ensure all services are able to operate free from unacceptable interference. This is a very real issue that is on-going at the WRC preparatory process. The terrestrial mobile industry is currently seeking 33 GHz of spectrum for 5G mobile terrestrial services, much of which is in bands already allocated to satellite communications and some of which is designated for satellite user terminal use Despite these existing satellite allocations and identifications, the wireless industry wants full and clear access to these bands — without any protections for the satellite, even though previous WRCs have recognized the need for spectrum for ubiquitous use of approximately four GHz of spectrum for satellite user terminals. This remains a critical issue for the industry and also for my company, as we are far along in the construction process of advanced broadband satellites in these bands. It would be unfortunate if the satellite industry is limited in the role it can play in the 5G network and in the future because of a lack of access to spectrum or access without required protections from interference.

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