Authorized for Public Release 

Spectrum 101 

An Introduction to National Aeronautics and Space 

Administration Spectrum Management 

February 2016 
i 

Table of Contents 

1. Introduction ................................................................................................................................. 1 

1.1 Document Structure ...................................................................................................................... 1 

1.2 What is Spectrum and Why Is It Important? ................................................................................ 1 

1.3 Sources of Increased Congestion and Contention ........................................................................ 3 

1.4 Spectrum Opportunities and Risks for National Aeronautics and Space Administration ............ 3 

1.5 Way Forward ................................................................................................................................ 4

2. Spectrum Basics ...........................................................................................................................6 

2.1 Overview .......................................................................................................................................6 

2.1.1 Spectrum as “Fuel” .......................................................................................................6

2.2 Band Designators .........................................................................................................................7 

2.3 What is Spectrum Management? ..................................................................................................9 

2.3.1 Spectrum Allocation .....................................................................................................9 

2.3.2 Spectrum Authorization .............................................................................................10 

2.3.3 Spectrum Engineering (Technical Standards) ...........................................................10 

2.3.4 Spectrum Compliance ................................................................................................11 

2.4 How It Works ..............................................................................................................................11 

2.4.1 Active vs. Passive Services ........................................................................................12 

3. Domestic and International Spectrum Regulatory Environment .........................................13 

3.1 National Spectrum Management – Dual Agency Management .................................................13 

3.1.1 National Telecommunications and Information Administration (NTIA) ..................15 

3.1.2 Federal Communications Commission (FCC) ...........................................................16 

3.2 International Spectrum Management .........................................................................................18 

3.2.1 International Telecommunication Union (ITU) .........................................................18 

3.2.2 US Engagement in the ITU Process ...........................................................................18 

3.2.3 International Spectrum Issues and NASA Equities ....................................................20 

3.2.4 NASA Engagement with Other 

 International Entities Concerned with Space Sciences Spectrum ..............................21 

4. NASA Spectrum Organization and Management ..................................................................23 

4.1 NASA Spectrum Organization ...................................................................................................23 

4.2 NASA Frequency Allocation and Assignment 

Process and Procedures ...............................................................................................................25 

4.2.1 Frequency Allocations ....................................................................................................... 25 

4.2.2 Frequency Assignments ..................................................................................................... 26 

5. NASA Spectrum Use ..................................................................................................................28 

5.1 Overview .....................................................................................................................................28 

5.2 Earth Science ..............................................................................................................................30 

5.3 Space Science..............................................................................................................................32 

5.4 Human Space Exploration ..........................................................................................................34 

5.5 Aeronautics and Space Technology Development .....................................................................35 
ii 

6. National Spectrum Issues and NASA Equities ........................................................................37 

6.1 Mobile Broadband ......................................................................................................................37 

6.2 National Broadband Plan ............................................................................................................38 

6.2.1 Evolving Auction Policy ............................................................................................38 

6.3 Spectrum Sharing ........................................................................................................................40 

6.3.1 Sharing in 3.5 GHz .....................................................................................................40 

6.3.2 Sharing in the 5 GHz Band .........................................................................................41 

6.4 “New Space” Issues ....................................................................................................................42 

6.5 Global Positioning System Issues ...............................................................................................44 

7. Conclusion ..................................................................................................................................46 

Attachment A – Process for Spectrum Authorization .......................................................................48 

Attachment B – NASA WRC-15 Objectives and Results ................................................................49 

Attachment C – NASA WRC-19 Objectives ....................................................................................54 

Attachment D – List of Acronyms ....................................................................................................57 

Attachment E – List of Figures .........................................................................................................59 

Attachment F – List of Tables ..........................................................................................................60 

 
iii 

Executive Summary 

Electromagnetic spectrum is the valuable but limited resource that makes possible virtually every 

mission that the National Aeronautics and Space Administration (NASA) undertakes, including in 

the areas of earth science, space science, human space exploration and aeronautical research. Yet 

even as spectrum access is growing increasingly important for NASA missions, the migration of 

the Internet from wireline platforms to the world of mobile communications is creating 

unprecedented pressure for more spectrum capacity to be made available for commercial wireless 

broadband services. 

What is Spectrum? The basic building block of radio communications are radio waves. The key 

characteristics of spectrum are the propagation features and the amount of information that signals 

can carry. A signal is broadly defined as a detectable quantity (e.g., current, voltage, 

electromagnetic field) that varies in time. An important signal for radio communications is one 

where the quantity varies as a periodic sine wave. Frequency is the number of cycles that occur in 

one second and is defined in units of Hertz (Hz), which is another name for cycle per second. The 

frequency of a signal is the reciprocal of its period. The amplitude of the signal is half the peakto-peak separation of the quantity that is changing with time, e.g., voltage. In general, signals sent 

using the higher frequencies have lower propagation distances but a higher data-carrying capacity 

and the opposite for longer wavelengths with lower frequencies makes up for the Radiofrequency 

(RF) spectrum. The range from 3 kiloHertz (kHz) to 300 GigaHertz (GHz) that may be used for 

wireless communication. Shorter wavelengths with higher frequencies make up the optical 

spectrum, while the part of the spectrum that can be seen is the visible spectrum. NASA relies on 

a range of tools for communicating and creating images utilizing almost every single component 

of the electromagnetic spectrum in one way or another. 

This report is designed to provide a better understanding of basic issues for NASA spectrum access 

and management by addressing: what spectrum is; how it is managed; key topics with respect to 

international and domestic policy decisions; how NASA organizes its spectrum management 

activities; opportunities and challenges; and future spectrum requirements for space missions. 

Individual sections are modular and designed to be read either in sequence or separately to address 

specific issues based on the following chapters: (1) Introduction; (2) Spectrum Basics; (3) 

Domestic and International Spectrum Regulatory Environment; (4) NASA Spectrum Organization 

and Management; (5) NASA Spectrum Use; (6) National Spectrum Issues and NASA Equities; (7) 

International Spectrum Issues and NASA Equities; and (8) Conclusion. 

Introduction: Like all federal spectrum users, NASA requires assured access to spectrum to reflect 

the long-term nature of investments, in systems – including satellites – designed to remain in 

operation for decades, versus the 18-month lifecycle of new cellphones. Thus, new commercial 

technology trends present both opportunities and challenges. In addition, passive scientific use of 

spectrum – for example in the form of Earth remote sensing satellites that glean weather and 

climate information – must be protected from unwanted interference in the face of expanding 

activity from active services, such as wireless broadband. 

Spectrum Basics: A transmitter generates a radio wave, which is then detected by a receiver. An 

antenna allows a transmitter to send energy into space and a receiver to pick up energy from space. 
iv 

Transmitters and receivers are typically designed to operate over a limited range of frequencies. 

Use of the radio spectrum is regulated, access is controlled and rules for use are enforced because 

of the potential for interference between uncoordinated uses. Spectrum is scarce because at any 

time and place, one use of a frequency precludes its use for another purpose. This has given rise 

to technological innovation and regulatory flexibility to increase the extent to which spectrum is 

shared between different users, either on the basis of time or geography. 

Regulatory Environment: In the US, two main policy bodies oversee spectrum use – the 

Department of Commerce’s National Telecommunications and Information Administration 

(NTIA) and the Federal Communications Commission (FCC). For federal spectrum, NTIA is the 

lead authority and for non-federal spectrum, the FCC has regulatory purview. Both agencies work 

together to ensure that policy decisions promote spectrum use consistent with both US economic 

interests and government user requirements. The dual management framework used in the US is 

unique in the world; most other countries have a single government agency perform the spectrum 

management function over both public and private sector uses. 

US activities regarding international frequency management are carried out under the leadership 

of the Department of State (DoS), whose role is to ensure the US speaks with one voice and that 

all applicable precedents and treaties are followed. 

International regulation and coordination of spectrum use occurs through the International 

Telecommunication Union (ITU), in compliance with a set of international rules and regulations 

(also known as the Radio Regulations). The ITU is the UN agency for matters dealing with 

information and communications technology. The State Department, along with NTIA and the 

FCC, oversees US preparations for ITU meetings. The ITU publishes the Radio Regulations (RR) 

as agreed at World Radiocommunication Conferences (WRCs), which occur every three to four 

years and update the RR, including spectrum allocations to various services. ITU member nations 

generally develop national frequency management regulations consistent with the RR. 

NASA Spectrum Management: Within this overarching national policy framework, NASA 

organizations manage the Agency’s use of spectrum and ensure NASA access to spectrum for all 

missions using space-based and ground-based assets. The NASA Spectrum Management Program 

ensures that all NASA activities comply with national and international rules and regulations 

applicable to spectrum use and facilitates securing spectrum and orbital resources (both 

domestically and internationally) to enable aeronautical and space mission requirements. 

Agency spectrum management responsibilities reside in the Space Communications and 

Navigation (SCaN) program office. SCaN’s Deputy Associate Administrator oversees the overall 

planning, policy development, and administration of the NASA Spectrum Management Program. 

The Director of Spectrum Policy and Planning oversees: NASA activities to obtain adequate 

international and national allocations of frequency bands; to pursue coordination of proposed 

NASA frequency use with other domestic and foreign users of the frequencies; and to obtain 

approval of frequency assignments by NTIA. The National and International Spectrum Program

Managers implement spectrum management initiatives and day-to-day spectrum management 

activities. They represent NASA in national and international fora, including committees and 

working groups responsible for developing frequency allocations and associated technical and 
v 

procedural rules. Center Spectrum Managers provide the latest communications requirements 

regarding implementation of projects and missions at the Center to the National and International 

Spectrum Program Managers. 

NASA has adopted procedures for requesting frequency assignments and obtaining new frequency 

allocations in order to effectively implement national and international spectrum management 

policy. In almost all cases, identification of spectrum support for NASA needs is focused on 

frequency bands allocated nationally and internationally for the particular radio service for which 

the Agency requires support. This includes both terrestrial use (e.g. fixed, mobile, radiolocation, 

radionavigation and other terrestrial radio service allocations) and space use (e.g., space radio 

service allocations that support the US space programs). 

NASA Spectrum Use: NASA’s investigations of the universe are accomplished mainly through 

the use of unmanned automated spacecraft. These missions employ both passive and active 

instruments operating at various frequencies to measure data from the Earth, planets, Sun, and 

other phenomena. They require highly reliable communications, often over long periods of time 

and at great distances, to guide and control the spacecraft and to bring back the images and new 

scientific data they collect. NASA’s spacecraft must be: tracked and controlled; the health, 

condition, and safety of the spacecraft must be monitored; and the scientific data that is obtained 

must be transmitted to mission operators. Channels are needed for robust, low data rate 

communications designed for critical Tracking, Telemetry, and Commanding (TT&C), and in the 

case of crewed spacecraft, for voice services. Still other channels are needed for high data rate 

communications for transmission of mission data. 

NASA operates a sophisticated global infrastructure, consisting of several component networks, 

including the Deep Space Network (DSN), which is used to support scientific spacecraft; Space 

Network (SN), which provides tracking and data relay for spacecraft, satellites, and expendable 

launch vehicles using space and ground segments. It includes the Tracking and Data Relay 

Satellite System (TDRSS); and Near Earth Network (NEN), which consists of ground stations 

owned by NASA, commercial entities, and other partners that provide communications and 

tracking services to missions in the near earth region. 

Earth science research at NASA has turned space-based observing technology and scientific 

expertise to use for the study of Earth and its integrated system of land, ocean, atmosphere, ice, 

and biological processes. Spaceborne sensors, which rely on spectrum, are the only tools that can 

provide environmental data repetitively on a global scale. To support the intermediate and long 

term goals of understanding the Earth, NASA has developed numerous radio sensors designed to 

fly onboard spacecraft. 

NASA’s space science missions are designed to study the mysteries of the universe from origins 

to destiny, to explore the solar system, to discover planets around other stars, to search for life 

beyond Earth and to chart the evolution of the universe and understand its galaxies, stars, planets, 

and life. NASA’s scientific investigations are carried out via spectrum-dependent unmanned 

automated spacecraft. 
vi 

NASA efforts to open the frontiers of space by human exploration could not be accomplished 

without spectrum. In exploring space, NASA has brought together a wide range of technologies, 

machines and people in the development of such programs as the Space Transportation System 

(STS) and the International Space Station (ISS). NASA is developing the capabilities needed to 

send humans to an asteroid by 2025 and Mars in the 2030s. Yet another spectrum-reliant focal 

point for NASA initiatives is Aeronautics and Space Technology Development. NASA is focused 

on developing technology solutions that will eliminate barriers to growth for the civil aviation 

system and provide a safe, efficient national aviation system.

National Spectrum Issues: Key drivers of the explosive growth in mobile broadband include the 

development of smartphones and other mobile computing devices, the emergence of broad new 

classes of connected devices (the Internet of things) and the rollout of Fourth-Generation (4G) 

wireless technologies such as Long Term Evolution (LTE). Several portions of the radio spectrum 

that are under consideration to keep up with wireless industry spectrum demand, including for 

unlicensed devices, carry potential implications for NASA equities. 

To meet this burgeoning commercial demand, in 2010, the FCC released a National Broadband 

Plan that called for making additional spectrum available for wireless broadband use – 500 

MegaHertz (MHz) by 2020, setting off a national spectrum “policy” race for even more spectrum 

bands to be considered to meet this goal. In a June 2010 Executive Memorandum, the President 

adopted this 500 MHz goal as US policy. A 2013 Executive Memo focused on increased sharing. 

Sharing efforts were further promoted when, in 2012, the President’s Council of Advisors on 

Science and Technology (PCAST) concluded that the traditional method for accommodating new 

services by clearing and reallocating portions of federal spectrum is not a sustainable model for 

national spectrum policy because it is too costly and takes too much time. PCAST made a series 

of recommendations for federal spectrum focused on large-scale sharing opportunities. 

NASA’s spectrum use is also affected by the needs of the growing commercial space sector, which 

has grown beyond the provision of basic communications and broadcasting services through 

satellites, to the provision of Earth resources information and development of new markets such 

as space tourism. The private sector is developing launch vehicles and facilities, as well as 

payloads, which require access to spectrum resources. To support the increased spectrum 

requirements arising from the growth of this sector, NASA is working with federal regulators to 

assess ways that federal spectrum traditionally used by NASA for its own operations can be made 

available, when needed, by private sector stakeholders for commercial launches and operations in 

space. 

International Issues: Because NASA missions require spectrum access on a global basis, NASA 

must influence developments in the international arena to ensure that its capabilities that are 

spectrum-dependent will have access to spectrum where and when needed. There are two paths 

within the US for the development of spectrum management rules and procedures contained in the 

international RR. One is a technical path where engineering studies concerning radio matters are 

conducted, which provide technical bases for international RR; the other is a more political path 

where preparations leading to a WRC involve discussions in domestic and international bodies. 

NASA participates in both domestic and international forums in making the technical studies 

necessary to promote and protect operations in the space science services. It also participates in 

bilateral and multilateral discussions, where negotiations occur that could affect these operations. 
vii 

As with domestic spectrum policy trends, WRC issues in recent conference cycles have faced 

pressures relating to the dynamic tension between public sector users and commercial mobile 

wireless providers around the globe. Often, there is an interplay between domestic and 

international policy directions, including an interest on the part of US technology developers in 

the identification of certain bands for mobile broadband applications as part of the WRC process 

to help create further leverage for such bands being put into play for commercial reallocation at 

home (for example the 5 GHz bands.). 

At WRC-12, NASA succeeded in getting several items of specific interest included for 

consideration on its agenda and subsequently approved at WRC-15,: (1) A possible Earth 

Exploration Satellite Service (EESS) uplink allocation in the 7-8 GHz range to help alleviate 

congestion in the 2 GHz bands; (2) A review of current limits on use of 410-420 MHz for Space 

Research Service (SRS) operations; (3) An expansion of 600 MHz around 9.5 GHz to support 

EESS (active) operations; and (4) Consideration of nanosat/picosat regulatory issues. 

While NASA remains vigilant about a range of potential WRC issues that could affect its 

operations, there are several spectrum access issues that raise potentially higher concerns. These 

include: (1) spectrum allocations for mobile broadband/International Mobile Telecommunication 

(IMT); (2) increasing broadband spectrum for the fixed satellite service; and (3) various proposals 

for spectrum in or adjacent to passive sensing bands. 

Conclusion: The spectrum management environment, which continues to be shaped by advanced 

technology capabilities, evolving policy frameworks and emerging operating requirements, poses 

both opportunities and challenges for NASA spectrum equities. NASA remains committed to 

proactively addressing both to meet its own mission requirements and help to contribute to 

balanced policy decisions regarding spectrum access. US policymakers are confronting what 

industry has described as a spectrum capacity crunch, with several bands that are under study for 

future wireless industry use carrying potential implications for NASA equities. At the ITU, the 

ITU-Radiocommunications Sector (ITU-R) is addressing future demand challenges, as well, as it 

works to finalize its vision of the connected future via planning efforts for Fifth-Generation (5G) 

Wireless. Simply put, challenges and opportunities in this complex electromagnetic spectrum 

environment are redefining how NASA carries out its roles as a proactive spectrum steward. 
1 

Chapter 1 

1. Introduction 

Spectrum use is an essential element of NASA global missions and activities, ranging from satellite 

communications, earth remote sensing, and weather monitoring to disaster response, satelliteaided search and rescue and space weather forecast. Spectrum is the “lifeblood” that enables the 

execution of virtually every mission that NASA undertakes – whether in the areas of earth science, 

space science, human space exploration, or aeronautical research. These initiatives depend on 

electromagnetic spectrum to deliver important public benefits, including scientific advances, 

contributions to jobs in the aerospace industry and technology transfer to commercial markets. 

1.1 Document Structure 

This paper has been developed to provide background and perspective on basic issues and trends 

for NASA spectrum management. This includes explanations of what spectrum is; how it is 

managed from a regulatory, technology and engineering perspective; who the major players are 

with respect to international and domestic policymaking; how NASA organizes its own spectrum 

management activities; current spectrum management opportunities and challenges for the 

Agency; and future spectrum requirements for space missions. Respective sections in the 

document are modular and are designed to be read either in sequence or separately to address 

specific issue areas. Accordingly, the paper is divided into the following chapters: 

Chapter 1: Introduction 

Chapter 2: Spectrum Basics 

Chapter 3: Domestic and International Spectrum Regulatory Environment 

Chapter 4: NASA Spectrum Organization and Management

Chapter 5: NASA Spectrum Use 

Chapter 6: National Spectrum Issues and NASA Equities 

Chapter 7: International Spectrum Issues and NASA Equities 

Chapter 8: Conclusion 

1.2 What is Spectrum and Why Is It Important? 

Frequency bands have relative advantages and disadvantages, and are chosen depending on the 

characteristics needed to carry out a mission or provide a service. NASA uses spectrum across a 

broad array of frequency ranges (see Figure 1.1). 

In addition to the usable electromagnetic spectrum being a scarce resource, many prime pieces of 

Chapter 1 Purpose: To provide an overview of why assured spectrum access is critical to 

all of NASA’s missions, how the electromagnetic spectrum environment in which NASA 

operates is changing and how the Agency is responding.
2 

spectrum “real estate” (bands that are appropriate for certain uses) are attractive to both 

government and private sector users. This is because the propagation characteristics that make 

certain bands useful for government purposes also make them similarly useful for commercial 

wireless services. These properties include the ability of radiowaves to penetrate terrain, travel 

long distances or pass through buildings or cloud cover. While signals at lower frequency bands 

(e.g., below 3 GHz) can propagate for miles and pass with relative ease through structures, 

millimeter wave signals (e.g., above 30 GHz) can travel only a few miles and do not penetrate 

buildings well for terrestrial applications.i

 

Across the US economy, mobile broadband is emerging as a disruptive technology (see Figure 

1.2) because it represents the convergence onto new platforms of two major transformational 

communications trends  the Internet and wireless capabilities. Wireless broadband is an 

economic growth engine in the US and a cornerstone of technological competitiveness. At the 

same time, spectrum enables a broad range of federal government services and applications, 

including NASA operations.

All spectrum auctioned to commercial carriers so far by the FCC, which is the US regulator with 

purview over commercial spectrum, has been below 3 GHz. However, millimeter wave bands are 

also under study for potential broadband applications. Spectrum above 30 GHz can facilitate more 

densely packed communications links to provide efficient use and secure transmissions. 

Figure 1.1: Representative NASA Spectrum Use 

Figure 1.1: Representative NASA Spectrum Use 
3 

Regulatory restrictions or 

requirements (the spectrum equivalent 

of “zoning”) also affect how useful a 

piece of spectrum may be for certain 

kinds of services or users. One 

example are the limits of power levels 

in a particular RF band in order to 

avoid causing harmful interference to 

systems in adjacent or nearby bands.ii

 

1.3 Sources of Increased 

Congestion and Contention 

All these factors make spectrum a 

valuable but limited resource. In the 

commercial world, contention for 

access to federal government bands is 

growing. Several federal bands are 

the focus of the National Broadband 

Initiative, for which the White House 

has set a goal of making an additional 

500 megahertz (MHz) of federal and 

non-federal spectrum available for 

mobile broadband use by 2020. 

Several bands that are under study for future wireless industry use carry potential implications for 

NASA equities. In other cases, new advanced wireless broadband uses that are entering spectrum 

bands adjacent to current NASA operations may impact Agency capabilities and require an 

adjacent band compatibility analysis to ensure that NASA missions do not encounter harmful 

interference and can continue without interruption. Global Positioning System (GPS) capabilities 

on which NASA relies face increased challenges with regard to the potential for harmful 

interference as new spectrum “neighbors” seek access to adjacent or nearby bands. 

Policymakers have embraced an approach of increasingly making new capacity available through 

sharing, as well as the traditional methods of relocating and clearing incumbent users to repurpose 

bands to the private sector. These efforts are focused on bands above the traditional “beachfront” 

spectrum sought by wireless carriers at auction (i.e., below 3 GHz). Policymakers are assessing 

how some of these bands can be shared, including as part of a tiered system of access between 

government incumbents, private sector licensees and unlicensed applications. The PCAST issued 

a landmark report in 2012 that advanced this tiered concept of sharing. It made a series of 

recommendations for making additional federal spectrum available on a shared basis for 

commercial wireless broadband use.iii

1.4 Spectrum Opportunities and Risks for NASA 

NASA spectrum requirements are complex, unique and evolving to support its critical missions. 

Figure 1.2: Cisco Forecasts Mobile Data Traffic 

(2014-2019)
4 

NASA uses radio spectrum to track, command and control spacecraft from mission launch to 

completion, to collect scientific/environmental information using a variety of sensors, and to 

communicate collected information to Earth facilities, either directly or through relay satellites. 

Spectrum access for human exploration enables ISS operations, development of commercial 

spaceflight capabilities and human exploration beyond Low-Earth Orbit (LEO). To explore space, 

NASA has brought into play a wide breadth and depth of technologies, machines and people in 

the development of programs such as the STS and the ISS. All of these capabilities include 

spectrum access as a critical component, including as part of developing the capabilities needed to 

send humans to an asteroid by 2025 and Mars in the 2030s. 

In comparison to commercial wireless applications, many aspects of spectrum-based NASA 

mission capabilities are designed for specific scientific purposes, for which no commercial 

substitute is available. Like all federal spectrum users, NASA requires assured access to spectrum 

to reflect the long-term nature of investments, in systems  including satellites  designed to 

remain in operation for decades, versus the 18-month lifecycle of new cellphones. Thus, new 

commercial technology trends regarding commercial applications and services present both 

opportunities and challenges. 

In addition, passive scientific use of spectrum – for example, in the form of Earth remote sensing 

satellites used to glean weather and climate information – need to be protected from unwanted 

interference in the face of expanded activity from active services, such as wireless broadband.iv 

The challenge is that these important NASA systems and initiatives represent billions of dollars in 

investment and continue to provide vital services to the public, which are sometimes harder to 

quantify in economic terms than is the case for wireless broadband. 

1.5 Way Forward 

In a period of increased demand for spectrum, including NASA’s, the development of spectrum 

policy that meets all users’ needs has been challenged by economic, mission, and technology 

considerations. In general, policymakers have attempted to strike a balance between unlicensed 

wireless operations, which prefer cost-free methods of access to bands without guarantees of 

protection against harmful interference, and additional spectrum for licensed operators, which 

generate significant revenue through auction but require extensive clearing and sharing efforts to 

make spectrum usable. 

Against this backdrop, NASA is an effective spectrum steward, harnessing technology to use 

limited spectrum resources more efficiently and effectively to address current requirements and to 

prepare for future needs for NASA’s space communication and navigation services and global 

terrestrial communication services. NASA’s approach to these spectrum roles and responsibilities 

is guided by a focus on safety, mission success, and risk management. 

As part of this stewardship approach, the NASA Spectrum Management program provides the 

overall planning, policy, coordination and implementation necessary to ensure adequate access to 

and protection of electromagnetic spectrum in support of NASA’s present and future 

programmatic goals. The Spectrum Management Division, located within the Human Exploration 

and Operations Mission Directorate (HEOMD) maintains NASA Policy Directives, NASA 
5 

Procedural Requirements, and other spectrum guidance documents, as needed. NASA missions 

requiring the use of the electromagnetic spectrum for communications or sensor operations follow 

the process outlined in Attachment A. 

i See FCC Office of Engineering and Technology Bulletin No. 70, July 1997, “Millimeter Wave Propagation: 

Spectrum Management Implications.” It is important to note that for space-based operations, windows in the 

atmosphere exist that allow spaceborne instruments to see to the Earth’s surface or to various layers in the 

atmosphere. 

ii The amount of mobile data offloaded to WiFi networks rose by 875 percent in the US in 2013, as wireless carriers 

tried to address growing strain on their own networks. This represents remarkable growth given that WiFi 

offloading was such a nascent trend in 2010 that it was not accounted for in the FCC’s National Broadband Plan. 

iii See PCAST report Realizing the Full Potential of Government-Held Spectrum to Spur Economic Growth, 2012. iv See National Academies Study, Spectrum Management for Science in the 21st Century, November 2010.

                                                            
6 

Chapter 2 

2. Spectrum Basics 

2.1 Overview 

The electromagnetic spectrum refers to the phenomena of electromagnetic waves, which propagate 

through space at different radio frequencies. Longer wavelengths with lower frequencies make up 

the radio spectrum, which is typically the frequency range from 3 kHz to 300 GHz that may be 

used for wireless communication. Shorter wavelengths with higher frequencies make up the 

optical spectrum, while the part of the spectrum that can be seen is the visible spectrum. NASA 

relies on a range of tools for communicating and creating images utilizing almost every single 

component of the electromagnetic spectrum in one way or another. 

2.1.1 Spectrum as “Fuel” 

RF spectrum enables a broad range of wireless applications, including mobile broadband 

smartphones, radio and television broadcasting, GPS position locating, aeronautical and maritime 

radio navigation, satellite command and control, and remote sensing of the atmosphere and surface 

of the Earth and planets. 

Radio waves constitute the basic building block of radio communications. Like waves in the 

ocean, they can be focused and bent and, like a wave traveling through water, have a wavelength 

(i.e., distance between wave crests) and a frequency (i.e., number of wave crests passing a point 

in a unit of time). Frequency is measured in the unit hertz (Hz), referring to a number of cycles 

per second.i

 

Bandwidth is the portion of spectrum that a given communications system can use (a system that 

operates on frequencies between 150 MHz and 200 MHz has a bandwidth of 50 MHz). A 

transmitter typically seeks to communicate with a particular receiver and the transmitting antenna 

directs the majority of the signal toward that receiver (the receiving antenna is most sensitive to 

signals coming from the direction of the transmitter). At the same time an antenna radiates signal 

at lower levels and can receive signals from all directions. An interfering signal will be amplified 

and detected like the desired signal once it enters the receiver.ii

To avoid interference, more than one person usually cannot transmit radio signals at the same 

frequencies, at the same time, in the same direction. As soon as one user stops transmitting signals 

over a portion of the spectrum, another can immediately re-use it. Spectrum is scarce because at 

any time and place, one use of a frequency precludes its use for another purpose. At the same 

time, this scarcity has given rise to technological innovation and regulatory flexibility to increase 

Chapter 2 Purpose: To describe the basic elements of what electromagnetic spectrum is, 

how it is managed and the implications for the electromagnetic environment in which 

NASA missions operate. 
7 

the extent to which spectrum is shared between different users, either on the basis of time or 

geography (see Chapter 6). 

2.2 Band Designators 

Frequencies are often grouped in ranges called bands. There are numerous ways frequency bands 

have been designated. A common method is to use a letter designator to identify the various bands. 

The Institute of Electrical and Electronics Engineers (IEEE) has published a standard for the letter 

designation of RF bands (see Figure 2.1). These codes are used by some engineers for radar, 

satellite, and terrestrial communications. The ITU designates bands (see Figure 2.2). 

Figure 2.1: Letter Designation of RF Bands 

In the US, the two main policymakers who oversee spectrum use – the NTIA and the FCC – have 

divided the usable radio spectrum (0-300 GHz) into about 800 frequency bands, which are 

allocated to 34 radio services (e.g., fixed, radionavigation, mobile, broadcasting, and various 

satellite services) (see Chapter 3).

Frequency Range Wavelength Band 

3-30 MHz 100-10 m High Frequency (HF) 

30-300 MHz 10-1 m Very High Frequency (VHF) 

300-1000 MHz 100-30 cm Ultra High Frequency (UHF) 

1-2 GHz 30-15 cm L 

2-4 GHz 30-15 cm S 

4-8 GHz 15-7.5 cm C 

8-12 GHz 7.5-3.75 cm X 

12-18 GHz 3.75-2.5 cm Ku 

18-27 GHz 1.67-1.11 cm K 

27-40 GHz 11.1-7.5 mm Ka 

40-75 GHz 7.5 mm-4 mm V 

75-110 GHz 4 mm-2.73 mm W 

Figure 2.2: ITU Band Designation 

Table 2.1: Spectrum Bands Used by NASA 
8 

Band Frequency Range 

Very Low Frequency (VLF) 

Dynamic Spectrograph of a VLF "Whistler". 

(3 kHz-30 kHz) 

Low Frequency (LF) 

STEREO/WAVES (SWAVES) uses LF radio imaging to study coronal mass 

ejections. 

(30 kHz-300 kHz) 

Medium Frequency (MF) 

Non-Directional Beacons use MF radio frequencies to deliver directional 

information to aircraft. NASA and the Federal Aviation Administration (FAA) 

are working to improve non-directional beacon technology. 

(300 kHz-3000 

kHz) 

HF 

Also called “short wave” and used for long distance communications; NASA 

uses HF at test ranges. 

(3 MHz-30 MHz) 

VHF 

NASA utilizes the VHF band by airborne sensors to study the thickness of sea 

ice. 

(30 MHz-300 

MHz) 

UHF 

NASA astronauts use UHF systems as backups for their voice communication 

systems. NASA also uses these frequencies to remotely sense the Earth’s 

surface (e.g. soil moisture with the Soil Moisture Active Passive (SMAP) 

mission) and atmosphere. 

(300 MHz-3000 

MHz) 

Super High Frequency (SHF) 

Numerous NASA and National Oceanic and Atmospheric Administration 

(NOAA) missions use SHF frequencies to probe the Earth’s atmosphere and 

surface. The Tropical Rainfall Measuring Mission and Global Precipitation 

Measurement missions observe the structure of rain in 3 dimensions. 

(3 GHz-30 GHz) 

Tracking and Data Relay Satellite (TDRS) 

The current configuration consists of nine in-orbit satellites (four first 

generation, three second generation and two third generation satellites) 

distributed to provide near continuous information relay service to missions 

like the ISS. 

S band (2-4 GHz) 

Ku-Band (12-18 

GHz) 

Ka-band (27-40 

GHz) 

Extremely High Frequency (EHF) 

Numerous NASA and NOAA missions can use EHF frequencies to probe the 

Earth’s surface, although they primarily are used to probe the atmosphere. 

(30GHz-300GHz) 

Infrared (IR) 

The Geostationary Operational Environmental Satellite (GOES) satellites use 

IR technology to view and track hurricane paths. 

(.003 x 1014 Hz-4 x 

1014 Hz) 

Visible 

Terra uses the visible light spectrum to take true color images of the Earth and 

its features. 

(4 x 1014 Hz-7.5 x 

1014 Hz) 

Ultraviolet (UV) 

The Solar and Heliospheric Observatory is studying the sun- from its core to its 

outer corona to its outer wind. 

(7.5 x 1014 Hz-3 x 

1016 Hz) 

X-Ray 

The GOES satellites use an X-ray imager to photograph and study the sun. 

(3 x 1016 HzUpward) 

Gamma Ray/Cosmic Ray 

Gamma Rays or Cosmic Rays are used to further study the universe. 
9 

2.3 What is Spectrum Management? 

Spectrum management is the oversight of RF spectrum use. Use of the radio spectrum is regulated, 

access is controlled and rules for use are enforced because of the potential for interference between 

uncoordinated uses. In the spectrum management process, frequency bands are allocated for 

particular uses, and specific technical and operating rules, developed by spectrum managers, 

govern the use of spectrum within those allocations. As the complexity and sheer number of 

radiocommunication systems has grown, the responsibilities for coordinating spectrum use also 

have become more complicated. 

2.3.1 Spectrum Allocation 

Spectrum allocation is a distribution of 

frequencies to radio services. An 

allocation designates the use of a given 

band by one or more 

radiocommunication services. 

National and international tables of 

frequency allocations contain lists of 

these band designations. The US 

Table of Frequency Allocationsi

covers the radio spectrum between 9 

kHz and 300 GHz (see Figure 2.4).

The key characteristics of spectrum are 

the propagation features and the 

amount of information that signals can 

carry. In general, signals sent using the higher frequencies have lower propagation distances but 

afford more bandwidth and thus a higher data-carrying capacity. NASA's Earth Science Division 

sensors operate at specific frequencies depending on the physics of substances to be studied. 

Required sensor frequencies occur throughout the radio spectrum, from 1.4 GHz to beyond 300 

GHz. 

There are a number of considerations taken into account when spectrum allocations are made. 

These might include: the public need for and benefits of a proposed service; amount of spectrum 

required; potential for interference to/from other services; technical considerations, such as 

propagation conditions and apparatus limitations; and international considerations. 

2.3.1.1 Primary vs. Secondary Allocation 

The ITU and, in turn, individual national regulators designate spectrum allocations as primary or 

secondary. 

 Primary allocations grant specific services priority in using a particular swathe of allocated 

                                                            

i

 U.S. Frequency Allocation Chart as of October 2011. (2011, August 1). Retrieved October 16, 2015, from 

http://www.ntia.doc.gov/ 

Figure 2.4: Table of Frequency Allocations 
10 

spectrum. In cases where there are multiple primary services within a band, they have equal 

rights. A station has the right to be protected from any others that start operation at a later date. 

 Secondary allocations involve services that must protect all primary allocations in a particular 

band. Services operating in secondary allocations must not cause harmful interference to, and 

must accept interference from, primary users. All secondary service stations have equal rights 

among themselves in the same band.

2.3.2 Spectrum Authorization 

Authorization – via frequency assignments – is the process by which users are licensed to access 

the spectrum resource. An assignment is a frequency or set of frequencies allotted to a given radio 

station for use under specified conditions. This may involve assigning specific frequencies to 

users, assigning certain frequency bands or sub-bands to users who may be able to transfer such 

spectrum rights to others, or it may mean authorizing the use of specific categories of equipment 

(unlicensed devices). 

Spectrum authorization activities include analyzing requirements for proposed frequencies in 

accordance with national frequency allocations and any applicable technical standards in order to 

select the most appropriate frequencies for radiocommunication systems. These activities also 

include actions to coordinate proposed assignments with existing assignments and to protect 

radiocommunication systems from harmful interference. An operator is assigned a frequency or 

set of frequencies in order to provide communications services, and this assignment of frequencies 

is done in a way to avoid harmful interference with other users of the spectrum. Spectrum 

authorization strategies ensure proper radio spectrum use, facilitate reuse, and achieve spectrum 

efficiency. 

2.3.3 Spectrum Engineering (Technical Standards) 

There are technical standards that describe procedures for how spectrum is used (spectrum 

operating standards) and standards that state conditions of apparatus compliance (radio equipment 

standards). 

 Spectrum operating standards state the minimal technical requirements for the efficient use of 

a specified frequency band or bands. 

 Equipment standards involve certification of radio equipment such as transmitters, receivers 

and antennas in order to determine compliance with radio operating standards. 

In general, technical standards are important to users of radio services and radio equipment since 

operators rely on them as a basis for preventing interference and for ensuring that radio systems 

perform as designed. Standards documentation might include: general information describing the 

equipment and the application; an indication of licensing and certification requirements; spectrum 

channel plan arrangements; modulation techniques used by the equipment; transmitter power; and 

transmission limits for unwanted emissions. Radio equipment standards basically define the limits 

on how certain radio equipment can interfere with other equipment in either shared or nearby 

frequency assignments. Regulators typically use technical standards to determine how certain 

radio equipment will interact with other equipment in either shared or adjacent frequency 
11 

assignments. The mutual interaction of electronic equipment is known as “Electromagnetic 

Compatibility” (EMC). 

2.3.4 Spectrum Compliance 

Spectrum monitoring and compliance activities are needed to ensure user compliance with 

frequency allocations, terms of assignments and technical standards. These activities help users 

to avoid incompatible frequency usage through the identification of sources of harmful 

interference, and to resolve interference problems for existing and potential users. Ensuring 

compliance with national spectrum management regulations maximizes the benefit of the spectrum 

resource to society. 

2.4 How It Works

These spectrum management aspects all come into play as part of how the FCC and NTIA carry 

out their respective roles and responsibilities (see Chapter 3). 

Over the years, the FCC has used a variety of methods to assign spectrum for commercial users, 

including assigning mobile licenses as part of comparative hearings. In 1993, Congress authorized 

the FCC to use auctions to award spectrum licenses for certain wireless communications services. 

Besides auctions, there are other mechanisms that the FCC uses to make spectrum available for 

wireless services, including licensed and unlicensed spectrum. Some licensed frequencies are 

allocated for public safety. In spectrum designated as "unlicensed," users can operate without a 

license but must use certified radio equipment and comply with technical requirements (i.e., power 

limits). Under the Commission's rules, users of license-exempt bands do not have exclusive use 

of the spectrum and are subject to interference. Should harmful interference occur, the operator is 

required to immediately correct the interference problem or cease operations. Typically, 

unlicensed devices operate at very low power over relatively short distances, and often employ 

various techniques, such as dynamic spectrum access or listen-before-talk protocols, to reduce the 

interference risk to others as well as themselves. NTIA, on the other hand, assigns frequencies to, 

and amends, modifies, and revokes assignments for radio stations operated by federal users. NTIA 

also makes frequency allocations and establishes policies concerning spectrum assignment 

allocation and use. 

In some cases, different federal agencies also have various direct responsibilities for certain 

activities that have spectrum management implications, depending on the services and operations 

at issue. For example, an NTIA frequency assignment covers authorization for federal (civil, 

military) agencies to transmit from terrestrial or space radio stations. An FCC license, on the other 

hand, is required for permission to non-federal (i.e., commercial) entities to transmit from 

terrestrial or space radio stations. Other non-spectrum regulatory activities may influence 

spectrum authorizations and licensing. For example, the FAA issues licenses for commercial space 

launch and reentry activities to protect public health and safety, safety of property, and national 

security and foreign policy interests of the US consistent with its statutory authorities. 

 
12 

2.4.1 Active vs. Passive Services

Spectrum is also used by both active (transmitting and receiving) and passive (receive-only) 

services, both of which are utilized by NASA for its missions (see Chapter 5). Examples of active 

or radiating services include radar and advanced wireless broadband applications. Receive-only 

or passive services do not radiate and examples include the EESS and Radio Astronomy Service 

(RAS). 

At the World Radio Administrative Conference (WARC) in 1959 (a predecessor to the current 

WRC)iii, the ITU accepted the idea of a “passive service.” The WARC agreed the needs of radio 

astronomy and space science would be included in the international RR, including the Table of 

Frequency Allocations. The RAS was established. 

 An Extraordinary Administrative Conference for space communications in 1963 revised the 

frequency allocation table laid down by the 1959 WARC, to provide frequency allocations 

for radionavigation-, meteorological- and communication-satellite services and for space 

research and radio astronomy. 

 At the ITU’s WARC for Space Telecommunications in 1971 (WARC-71), the EESS was 

established. Frequencies were allocated for the transmission of data from space to Earth in 

order to accommodate the needs of satellite programs that use sensors to obtain data about the 

Earth’s environment. 

i

 One thousand hertz is referred to as a kilohertz (kHz), 1 million hertz as a megahertz (MHz), and 1 billion hertz as 

a gigahertz (GHz). 

ii See NTIA Web site. http://www.ntia.doc.gov/book-page/regulating-use-spectrum. iii For further explanation of WRC, see section 3.2. 

                                                            
13 

Chapter 3 

3. Domestic and International Spectrum Regulatory 

Environment 

Given the critical importance of radio frequency spectrum, governments participate in both 

international and national spectrum management policymaking bodies. NASA plays an active role 

in all these organizations. 

3.1 National Spectrum Management – Dual Agency Management 

In the US, two federal agencies have responsibilities for management of spectrum. For federal 

spectrum, NTIA is the lead authority. For non-federal spectrum, the FCC has regulatory purview. 

The Communications Act of 1934 divided authority over spectrum between the executive branch 

(federal uses) and the FCC (non-federal uses). Historically, the White House Office of 

Telecommunications Policy administered frequency assignments for federal uses. In 1977, this 

White House authority was delegated to the Commerce Department, through the Assistant 

Secretary who administers the NTIA.i As an independent agency, the FCC is under direct 

Congressional oversight. 

The NTIA Organization Act stipulates that the Assistant Secretary’s responsibilities include 

assigning frequencies to federal government users, establishing policies for spectrum assignment 

allocation and use, and providing departments and agencies with guidance “to assure that their 

conduct of telecommunications activities is consistent with these policies.” 

The NTIA and FCC are required to work together to ensure that spectrum policy decisions promote 

efficient use of the spectrum consistent with both US economic interests and national security 

requirements. NTIA can file comments on behalf of the Administration and as part of its role in 

managing use of federal spectrum in FCC proceedings. In such cases, it cites its role as the 

President’s principal adviser on telecommunications policies. To accomplish these goals of 

economic benefits balanced with national security needs, the Chairperson of the FCC and the 

Assistant Secretary for Communications and Information, NTIA signed a Memorandum of 

Understanding (MOU) in January 2003 that formalized their long-standing cooperative 

relationship. 

Under the MOU, the Chairperson of the FCC and the Assistant Secretary for Communications and 

Information agree to meet at least twice each calendar year to conduct joint spectrum planning. 

Further, they agree that their staffs will meet regularly to exchange information of mutual interest 

concerning spectrum management. Both agencies give notice to each other of all proposed actions 

Chapter 3 Purpose: To provide an overview of the various domestic and international 

regulatory agencies involved in the management of RF spectrum. 
14 

that could potentially cause interference to operations authorized by the other. Final action by the 

either agency, however, does not require approval of the other. 

 Figure 3.1: US Spectrum Management Process

The majority of all spectrum has been allocated for shared use between both federal government 

and non-federal government users, but both groups have exclusive access to some bands and 

federal spectrum is typically extensively shared among different government services and 

applications. Some shared bands allow significant interaction between government and nongovernment uses. For example, federal radio facilities allow private sector ships and aircraft to 

communicate and navigate. Federal law enforcement agencies communicate with their state and 

local government counterparts, and federal electrical power systems interconnect with non-federal 

power systems. The allocation plan changes to meet evolving domestic and international spectrum 

needs. 

The dual management scheme used by the US to manage spectrum is different than most other 

countries, which typically have a single government agency perform the spectrum management 

function over both public and private sector uses. Both approaches have advantages and 

disadvantages. When a single agency manages spectrum, it is much easier for those countries to 

arrive at a unified national position. The dual management scheme makes arriving at a single 
15 

position more challenging, but it ensures that private and government concerns are both 

considered. As the commercial potential of spectrum use is ever increasing, the kind of bifurcated 

system used in the US helps to ensure that decisions concerning commercial interests are balanced 

with their impact on government uses of spectrum. Similarly, decisions concerning government 

interests are made while taking into account commercial interests. 

Further details on the various federal spectrum agencies and advisory groups are discussed below: 

3.1.1 National Telecommunications and Information Administration (NTIA) 

As the executive branch agency principally responsible for advising the President on 

telecommunications and information policies, NTIA also manages the day-to day federal use of 

spectrum in planning for spectrum uses and granting specific frequency assignments to agencies. 

It performs its spectrum management function through the Office of Spectrum Management 

(OSM). OSM establishes plans and policies that are intended to ensure the effective, efficient, and 

equitable use of spectrum. This includes public safety operations and the 

coordination and registration of federal government satellite networks. It 

also satisfies the specific frequency assignment needs of federal agencies and 

provides spectrum certification for new federal agency radio communication 

systems. The NTIA Manual of Regulations and Procedures for Federal 

Radio Frequency Management is the guidebook for frequency authorization 

to federal agencies in the US. The manual defines the information required 

for obtaining frequency authorization and provides the standards and 

guidelines for frequency use. NTIA seeks collaboration through several groups, discussed below. 

Interdepartment Radio Advisory Committee (IRAC): IRAC assists NTIA in assigning frequencies 

to US government radio stations and in developing policies, programs, procedures and technical 

criteria for allocation management and use of spectrum. This includes coordinating federal 

spectrum use and resolving interference conflicts among federal agencies. In addition to NASA, 

the following agencies are members of the IRAC: the Departments of Agriculture; Army; Air 

Force; Commerce; Energy; Health and Human Services; Homeland Security; Interior; Justice; 

Navy; State; Treasury and Veterans Affairs; the US Coast Guard; the FAA; the General Services 

Administration; the National Science Foundation; the Broadcasting Board of Governors; and the 

US Postal Service. The FCC is not a formal member but has a designated liaison representative. 

The NASA IRAC representative is the Deputy Director of Spectrum Policy. 

NTIA reaches its decisions by using the consensus advice from the IRAC, NTIA staff technical 

and policy analyses, and, when appropriate, public input. This allows each agency to review 

proposals for new radio services and stations from other federal users (and non-federal users in 

bands where regulatory jurisdiction is shared by NTIA and the FCC) to determine if the new 

proposals will have an adverse impact on existing and planned operating systems. Affected users 

can then negotiate directly and develop a timely technical resolution to the potential problem. 

Each government agency decides – on the basis of factors such as policies, rules, regulations, 

frequency allocations, and the availability of frequencies – whether, what, and how many mission 

requirements can be fulfilled by using telecommunications systems. Each agency makes the 
16 

necessary technical studies, selects potential frequencies, coordinates with other agencies 

involved, and prepares and files an application with NTIA’s OSM’s Spectrum Services Division 

(SSD), for consideration by the Frequency Assignment Subcommittee (FAS) of the IRAC.ii

Other key policy advisory groups include: 

Policy and Plans Steering Group (PPSG): The NTIA’s Assistant Secretary has a coordination 

process - in the form of the PPSG - to ensure that Federal matters are considered as part of policy 

decisions and to resolve policy disputes. The PPSG consists of the Assistant Secretaries, or 

equivalent, with spectrum management oversight in agencies that have major spectrum issues. The 

PPSG provides advice to NTIA’s Assistant Secretary and helps resolve major contentious 

spectrum policy issues that affect the use of spectrum by federal and non-federal users. NASA’s 

Director, Spectrum Policy and Planning Division serves as part of this group, which was created 

as part of a series of recommendations that arose from an Executive Memorandum signed in June 

2003. 

Commerce Spectrum Management Advisory Committee (CSMAC): The CSMAC consists of 

private sector spectrum experts who advise the Assistant Secretary, NTIA on a broad range of 

issues regarding spectrum policy, including many issues specific to federal government users, 

although agencies do not have representation on CSMAC outside of NTIA’s own participation. 

The CSMAC is a federal advisory committee that has been in operation since 2006. In recent 

years, CSMAC has addressed issues ranging from potential user fees to sharing scenarios between 

federal and non-federal users as part of specific preparatory activities leading to the 2014 FCC 

Advanced Wireless Service (AWS)-3 auction. 

3.1.2 Federal Communications Commission (FCC) 

The FCC is directed by five commissioners, who are appointed by the 

President and are confirmed by the Senate for five-year terms. The President 

designates one of the Commissioners as Chairman (only three 

commissioners can belong to the same political party, so the party affiliation 

of the Chairman is always determined by which party is in control of the 

White House). FCC Commissioners make all regulatory decisions, except 

for those made on delegated authority at the agency’s bureau-level. FCC 

rules and regulations (allocations/standards) governing non-federal spectrum are maintained in the 

Code of Federal Regulations. 

NTIA works closely with the spectrum management components of the FCC, discussed below. 

Office of Engineering and Technology (OET): The OET advises the FCC on technical and policy 

issues pertaining to both wireless and wireline proceedings. In cooperation with other 

organizations in the FCC, OET directs staff work with respect to general frequency allocation 

proceedings and other proceedings involving technical issues. In addition, OET prepares 

recommendations for legislation concerning technical issues, and reviews recommendations for 

rulemaking involving technical proposals that are initiated by other offices. OET serves as the 

primary contact point between the spectrum management activity of NTIA and the FCC by 

providing liaison with the IRAC for the Commission. 
17 

Wireless Telecommunications Bureau (WTB): The WTB handles the FCC’s domestic wireless 

telecommunications programs and policies – except those involving satellite communications or 

broadcasting – including licensing and regulatory functions. The WTB is also responsible for 

implementing the FCC’s statutory authority to assign spectrum licenses by competitive bidding. 

International Bureau (IB): The IB serves as the focal point within the FCC for cooperation and 

consultation on international telecommunications matters with other federal agencies, international 

or foreign organizations, and appropriate regulatory bodies and officials of foreign 

governments. The IB develops, recommends, and administers policies, rules, and procedures for 

the authorization and regulation of international telecommunications facilities and services, 

including domestic and international satellite systems. The IB represents the FCC on international 

telecommunications matters at conferences and meetings, and directs and coordinates the FCC’s 

preparation for such conferences and meetings. The IB also oversees the international 

coordination of spectrum allocations and specific frequency and orbital assignments. 

Enforcement Bureau (EB): The EB is the primary unit within the FCC responsible for 

enforcement of provisions of the Communications Act, the FCC rules, FCC orders, and the terms 

and conditions of station licenses. The EB investigates alleged violations of the FCC’s technical, 

operational, and competitive rules, and recommends or issues appropriate enforcement actions. 

3.1.3 NASA Engagement with other Domestic Entities Concerned with Space Sciences 

Spectrum 

NASA participates in the Space-based Positioning, 

Navigation and Timing Executive Committee 

(PNT EXCOM). Space based PNT EXCOM 

covers GPS, GPS augmentation and other global 

navigation satellite systems. The National 

Committee is chaired by the Deputy Secretaries of 

Defense and Transportation. The membership includes top leaders for the Departments of State; 

Interior; Agriculture; Commerce; Homeland Security; the Joint Chiefs of Staff; and NASA. The 

PNT EXCOM has addressed timely policy issues as national regulatory decisions increasingly 

have created new challenges for GPS operations. Recent regulatory issues addressed by the PNT 

EXCOM that have had high visibility have included inputs to the FCC’s LightSquared regulatory 

proceeding. 

3.2 International Spectrum Management 

US activities regarding international spectrum management are carried out under the leadership of 

the DoS. The DoS is involved in all international aspects of spectrum management including 

bilateral discussions with neighboring countries about operations of radio systems near the borders. 

Its role is to ensure that the US speaks with one voice and that all applicable precedents and treaties 

are followed 
18 

International regulation and coordination of spectrum use occurs through the ITU, in compliance 

with a set of international rules and regulations. The DoS, along with NTIA and the FCC, oversees 

US preparations for meetings of the ITU.

3.2.1 International Telecommunication Union (ITU) 

The ITU was founded in 1865, and since 1947, it has been the UN’s agency for 

matters dealing with information and communications technology (see Figure 

3.2). Within the ITU, the ITU-R carries out activities concerning radio 

communications and spectrum management. The ITU publishes the international 

RR, which are the recognized framework for the use of the spectrum and have 

treaty status. ITU member nations generally develop national spectrum 

management regulations consistent with the RR. The ITU publishes the RR as agreed at WRCs 

(states remain sovereign and may operate systems in derogation of the RR, provided they do not 

cause and are willing to accept interference. Such national exceptions are usually listed in 

footnotes to the RR). 

Four of the ITU-R organizations affect spectrum and spectrum management: 

WRC: The WRC meetings occur periodically, about every four years. Each WRC has a specific 

agenda associated with specific radiocommunication services and updates the international RR, 

which include the allocations of spectrum to the various radio services. These allocations have 

worldwide effect except where regional or national requirements differ and regional members 

agree to these differences. 

Radio Regulations Board (RRB): The RRB approves the Rules of Procedure used by the 

Radiocommunication Bureau (BR) to register frequency assignments. It addresses matters 

referred by the BR that cannot be resolved by reference to the Radio Regulations or to the Rules 

of Procedure. It adjudicates interference conflicts among member nations. 

BR: The BR operates under the Rules of Procedure established by the RRB to achieve an orderly 

recording and registration of frequency assignments, and, when necessary, the associated orbital 

characteristics of satellites. It maintains the Master International Frequency Register. It also 

advises member nations and the RRB on technical matters of interference and spectrum use. 

Radiocommunication Study Group (SGs): The SGs evaluate a variety of questions relating to 

radiocommunication issues. The focus of their work is on the use of spectrum in terrestrial and 

space communications, the characteristics and performance of radio systems, the operation of radio 

stations, and the radiocommunication aspects of distress and safety matters. Currently there are 

six study groups, each of which is divided into permanent working parties. 

3.2.2 US Engagement in the ITU Process 

While the DoS has responsibility for all international negotiations concerning international 

spectrum usage, both NTIA and the FCC advise the DoS in this role. Each agency has 

responsibility to seek assurance that the multi-year preparatory effort for the WRC meets US needs 

and is supported by the best technical information available. 
19 

The international negotiation process occurs in cycles that match the occurrence of each WRC. 

Each WRC proposes Agenda Items (AIs) for the next WRC. These lead to a list of issues that 

must be resolved and proposals that must be generated. The US begins the WRC cycle by 

operating within a well-defined advisory committee process that precedes establishment of the US 

delegation and appointment of a head of delegation. Meetings are conducted throughout the cycle 

to prepare US positions and strategy. Negotiations are held in bilateral, multilateral, and regional 

conferences to garner support for US positions. US delegations to these conferences are 

comprised, for the most part, of those who have participated in the multi-year process that prepared 

the US proposals and supporting material. These individuals include career government 

professionals who are experienced in this type of negotiation and private sector individuals with 

extensive technical expertise who have participated in the preparatory process and past 

conferences. 

 NASA, as well as other federal agencies, submits proposals to the IRAC Radio Conference 

Subcommittee (RCS). Upon approval within the RCS, proposals are then coordinated with 

an FCC WRC Advisory Committee for acceptance by the private sector. In a similar fashion, 

private sector proposals are coordinated through the RCS for approval by the federal sector. 

Proposals are ultimately reconciled between the FCC and NTIA before going to the US DoS 

for submission to the conferences. 

 In general, technical studies of current interest are supplied to the US Study Group or 

appropriate Working Party by member agencies. 

 When approved by the Study Group or Working Party, they are forwarded to the National 

Committee of the US DoS’s International Telecommunications Advisory Committee for the 

Radiocommunication Sector for national policy review prior to being submitted to the ITU-R 

Radiocommunication Assemblies, Study Groups, Working Parties, or item specific Task 

Groups. 

 The results of these studies provide the technical bases for Radiocommunication Conferences. 

Significant technical interests for NASA are in the ITU-R Study Group concerned with the space 

science services, Study Group 7 and its Working Parties 7A, 7B, 7C, and 7D, which support federal 

and commercial space programs. In addition to the space sciences services, NASA also contributes 

to the work of Study Group 1 (Spectrum Management), Study Group 3 (Radiowave Propagation), 

Study Group 4 (Satellite Service), Study Group 5 (Terrestrial Services), and Study Group 6 

(Broadcasting Services). These efforts occur to assist the commercial industry in better meeting 

the long-term communications requirements of NASA, as well as to protect and promote NASA 

use of the spectrum. 
20 

3.2.3 International Spectrum Issues and NASA Equities 

NASA must maintain a steady awareness of developments in the international arena. The primary 

venue of concern is the ITU where the international rules and regulations for use of the radio 

spectrum are developed. 

Figure 3.2: ITU Structure 
21 

In preparation for WRCs, NASA participates in both domestic and international forums, providing 

technical studies necessary to promote and protect operations in the space science services. It also 

participates in bilateral and multilateral discussions, such as in meetings convened by the CITEL. 

As with domestic spectrum policy trends, WRC issues in recent 

conference cycles have faced pressures relating to the dynamic tension 

between public sector users and commercial mobile wireless providers 

around the globe. In early 2012, the ITU-R embarked on a program to 

develop “IMT for 2020 and beyond”. In 2015, the ITU-R finalized its 

vision of the “5G” mobile broadband connected society. This view of the 

horizon for the future of mobile technology was considered at WRC-15. 

At WRC-19, further deliberations on additional spectrum to support the 

future growth of IMT will take place. The entire process is planned to be 

completed by 2020 when draft new ITU-R Recommendations detailing specifications for the new 

radio interfaces are expected to be submitted for approval within ITU-R. Attachments B and C 

provide some details regarding WRC-15 and WRC-19, respectively. 

NASA has been historically successful in obtaining AIs for consideration at WRCs in support of 

NASA’s changing mission requirements and in reflection of NASA spectrum policy directions. 

NASA continues to be vigilant in protecting existing spectrum provisions from proposals that 

could affect its existing and planned operations. 

3.2.4 NASA Engagement with Other International Entities Concerned with Space Sciences 

Spectrum 

NASA’s responsibilities include informally regulating and overseeing (together with its partner 

space agencies) the spectrum allocations that have been made to the space science services by the 

ITU. In addition to meeting regularly with international counterparts such as the European Space 

Agency (ESA) and the Space Agency of Japan (JAXA), NASA leads the Space Frequency 

Coordination Group (SFCG) and the Interagency Operations Advisory Group (IOAG). These are 

organizations of space agencies that make agreements and provide recommendations about how 

best to use allocated frequency bands, and how to provide cross-support for each other’s missions. 

NASA also participates in activities of Inter-American Telecommunicaiton Commission (CITEL), 

an entity within the Organization of American States (OAS), which coordinate 

telecommunications matters in the hemisphere. Participation by NASA in the SFCG and CITEL 

is especially important because at ITU conferences, the SFCG provides a unified position from 

space sciences interests and CITEL provides a unified position from countries of the hemisphere. 

NASA is also the leader of the Consultative Committee for Space Data Systems (CCSDS); another 

world-wide group of space agencies that develop and promulgate standards for space hardware 

and software, for example, for spectrum efficient modulation techniques, that improve spectrum 

efficiency. 

i

 The NTIA Organization Act directs the Commerce Secretary to assign to the Assistant Secretary and the NTIA the 

responsibility for the performance of the Secretary's communications and information functions. These functions 

were transferred to the Assistant Secretary of Commerce for Communications and Information (Administrator, 

                                                            
22 

                                                                                                                                                                                               

NTIA) by Department of Commerce Organization Order 10-10 of Oct. 5, 1992. This authority and delegation has 

been codified in the NTIA Organization Act, Pub. L. No. 102-538, 106 Stat. 3533 (1992) (codified at 47 U.S.C. 901 

et seq.) 

ii The OSM/SSD, using a combination of computer and manual procedures, reviews the applications for accuracy, 

completeness, and compliance with regulations and procedures. FAS agendas are distributed to each FAS member 

agency for study regarding the protection of their existing assignments. OSM/SSD reviews the agendas to ensure 

adequate justification, compliance with policy and regulations, technical appropriateness, potential for major 

problems, whether or not spectrum support for the system, if applicable, has been certified by the Spectrum Planning 

Subcommittee, and whether there is a conflict with the assignments of the FAS non-member agencies. Each month 

the FAS considers pending items and takes action within established policy guidelines. 
23 

Chapter 4 

4. NASA Spectrum Organization and Management 

This chapter describes the NASA organizations that manage the Agency’s use of the 

electromagnetic spectrum and the general processes that are involved in securing NASA’s access 

to spectrum for all missions using space-based and ground-based assets. The NASA Spectrum 

Management Program ensures that all NASA activities comply with national and international 

rules and regulations applicable to use of the electromagnetic spectrum and facilitates securing 

spectrum and orbital resources (both domestically and internationally) needed to enable 

aeronautical and space mission requirements. 

Per NASA Policy Directive (NPD) 2570.5 and NASA Process Requirements (NPR) 2570.1, it is 

NASA policy that any NASA system that requires use of the electromagnetic spectrum for 

transmission, reception or both shall follow the spectrum regulatory rules and processes. NASA 

has a comprehensive procedural requirements document, NPR 2570.1 that provides step-by-step 

guidance to all programs, projects and activities on the process of obtaining spectrum access. 

In addition, the requirement for NASA’s spectrum management activities is codified in federal 

law, including the Communications Act of 1934, as amended, the Communications Satellite Act 

of 1952, the Commercialization of Space Act of 1983 and National Space Policy. 

4.1 NASA Spectrum Organization 

Agency spectrum management responsibilities reside in the SCaN program office, as delegated 

from the Associate Administrator, HEOMD, the NASA Spectrum Manager. 

SCaN’s Deputy Associate Administrator oversees the overall planning, policy development, and 

administration of the NASA Spectrum Management Program (see Figure 4.1). 

The Director of Spectrum Policy and Planning oversees NASA’s activities to obtain adequate 

international and national allocations of frequency bands, to pursue coordination of proposed 

NASA frequency use with other domestic and foreign users of the frequencies, and to obtain 

approval of frequency assignments to NASA by NTIA. The Director is also responsible for the 

planning of long-term national and international spectrum management initiatives aimed at 

improving the spectrum environment for NASA, including maintaining long-range spectrum 

forecasts to identify needed spectrum management initiatives. These forecast demands are, in turn, 

driven by the projected launch dates of planned missions and other spectrum needs. 

The National and International Spectrum Program Managers are responsible for the 

implementation of spectrum management initiatives and for day-to-day spectrum management 

activities. They represent NASA in national and international fora, including committees and 

Chapter 4 Purpose: To provide an overview of the NASA spectrum organization and its 

process for securing spectrum for mission requirements.
24 

working groups responsible for developing frequency allocations and associated technical and 

procedural rules. They maintain records of NASA frequency usage and track NASA’s efforts 

toward coordination and approval of proposed frequency usage. They also draft policy proposals 

and recommendations for consideration by national and international regulatory bodies, such as 

for the IRAC and ITU. 

Center Spectrum Managers have the responsibility to provide the latest communications 

requirements regarding implementation of projects and missions at the Center to the National and 

International Spectrum Program Managers. The National Spectrum Program Manager, in 

consultation with each Center Spectrum Manager and the International Spectrum Program 

Manager, provides an assessment of these spectrum requirements and the actions needed to fulfill 

them. The Center Spectrum Manager of the originating project is responsible for obtaining an 

approved frequency assignment(s) and has the overall responsibility for spectrum at the execution 

site. Each spectrum user within NASA is responsible for contacting his or her Center’s Spectrum 

Manager during the earliest phase of a planned project to convey its spectrum requirements. 

Figure 4.1: NASA Spectrum Management Organization 
25 

4.2 NASA Frequency Allocation and Assignment Process and Procedures 

NASA has adopted procedures for requesting frequency assignments and obtaining new frequency 

allocations in order to effectively implement national and international spectrum management 

policy. These procedures allow for a thorough, coordinated process from identification of Agency 

program/project needs to national and international recognition of actual frequency band usage 

and are outlined in the NPR 2570.1. 

4.2.1 Frequency Allocations 

In almost all cases, identification of spectrum support for NASA needs is focused on frequency 

bands currently allocated nationally and internationally for the particular radio service for which 

the Agency requires support. This includes both terrestrial use (e.g. fixed, mobile, radiolocation, 

radionavigation and other terrestrial radio service allocations) and space use (e.g., space radio 

service allocations that support the US space programs). 

When selecting operating frequencies, NASA must adhere to the National Table of Frequency 

Allocations published in the NTIA Manual and adhere to the standards and recommendations for 

spectrum use established by ITU and SFCG. 

Some terrestrial systems operated by NASA may be classified as major telecommunications 

systems. These are systems which, even though spectrum allocations currently exist, are required 

to be submitted to NTIA for certification of spectrum support, because they have large bandwidth 

requirements, new modulation techniques, novel applications, or are considered to have a 

significant impact on the existing electromagnetic environment. For these, NTIA has established 

a systems review process, for the purpose of certification of spectrum support, by which that use 

is coordinated within the US and internationally. 

Further, the use of a frequency that has been allocated to two or more services or is used by multiple 

federal government agencies often requires coordination with the other affected agencies. This 

coordination is handled unofficially prior to a formal frequency authorization request in order to 

address any interference concerns and to avoid any resulting delays in spectrum certification. 

However, when policymakers make decisions to reallocate certain bands of spectrum to different 

uses, or from federal to non-federal allocations, it may be necessary to relocate Agency operations 

elsewhere in the spectrum where appropriate allocations do not currently exist. Requirements to 

seek access to different spectrum also may arise when current bands used by NASA become 

congested as new scientific, technological, and commercial requirements emerge and take up 

additional capacity. As part of long-range planning for new systems, NASA also may seek access 

to bands that require allocation changes, as current bands used by federal space operations on a 

primary or a secondary basis become increasingly congested from other services and applications 

whose spectrum requirements are also growing. In such cases, the identification of the need for a 

new allocation may be made by reference to the Table of Frequency Allocations or as a result of 

the systems review process, which includes a study of current frequency band occupancy. 
26 

An example of this need for a new allocation occurred in recent years regarding Ka-band spectrum. 

As the spectrum used for communications links between ground stations and spacecraft in S-band 

and X-band became more heavily used and congested, NASA realized that spectrum at Ka-band 

might be required to accommodate communications for future missions. Spectrum for an uplink 

was needed to complement spectrum already allocated for space-to-Earth transmissions. NASA 

was successful at WRC-12 in achieving a new allocation at 22.55-23.15 GHz to complement 

spectrum at 25.5-27.0 GHz. 

In cases where new frequency allocations are deemed necessary, it is imperative that very longlead-times (i.e., ten years or longer) be allowed for the national and international processes which 

are required for new allocations. WRCs review, and if necessary, revise the RR. Since WRCs are 

conducted on a periodic basis (i.e., normally every three-four years), it is essential that NASA is 

prepared to identify new requirements well in advance of these conferences, so that supporting 

technical and regulatory information can be prepared and presented. NASA can seek to influence 

WRC outcomes, but only as part of the US governmental preparatory process. NASA promotes 

its position within the US delegation, which is comprised of other US federal agencies, nongovernmental entities and commercial/private companies. The delegation meets regularly and 

refines its position. Key members of the US delegation also attend preparatory meetings with 

other countries and other regional bodies to share their preliminary thoughts on AIs before the 

WRC. As mentioned earlier, each nation is sovereign, and the US seeks to incorporate WRC 

decisions into its National Table of Frequency Allocations. 

4.2.2 Frequency Assignments 

All Center activities are assigned frequencies by NTIA through the NASA IRAC FAS 

representative. The NASA FAS representative forwards these assignments to the appropriate 

Center Spectrum Manager upon completion of the frequency coordination process. The NASA 

FAS representative also informs the National Spectrum Program Manager when the assignment 

has been approved by NTIA. Based on this authorization, Center Spectrum Managers may issue 

Center RF Authorizations (RFA). 

The frequency assignment process (see Figure 4.2) is initiated at the user NASA center/facility 

and results in the issuance by NTIA of an RFA or Special Temporary Authorization (STA). If the 

use is not for a major terrestrial program or not for frequencies to be used for transmissions to and 

from space, the frequency assignment process is fairly simple. 

NASA has a specified step-by-step process to guide the process for both terrestrial and space 

assignments, which is outlined in the NPR 2570.1 (see Attachment A). For a federal system, the 

frequency authorization process is well defined by NASA procedures. For non-federal designated 

systems affiliated with or supported by NASA, the non-NASA owner and/or operator of the 

satellite and electromagnetic spectrum systems must obtain spectrum licensing through the 

appropriate FCC process. 
27 

Figure 4.2: Frequency Authorization Process
28 

Chapter 5 

5. NASA Spectrum Use

NASA’s needs for radio frequency spectrum have evolved and grown over the decades and include 

a wide array of programs and applications. NASA conducts missions encompassing space 

exploration, Earth science, basic scientific research, and technology development. Virtually every 

one of these endeavors requires use of the radio spectrum. 

NASA’s requirements for access to the radio spectrum are unique. There are no alternatives 

available to the Agency to command its complex spacecraft, since any use of landlines is 

impossible. NASA missions may operate at great distances from the earth, resulting in the need 

to receive and process very weak signals from spacecraft and to transmit commands with very high 

power to reach spacecraft. These missions employ both passive and active instruments operating 

at various frequencies to measure data from the Earth, planets, Sun and other phenomena. 

5.1 Overview 

NASA’s investigations of the universe are accomplished mainly through the use of unmanned 

automated spacecraft. Missions require highly reliable communications, often over long periods 

of time and at great distances, to guide and control the spacecraft and to bring back the images and 

new scientific data they collect. Because many deep-space missions continue for periods of several 

years, and because there are usually several missions in progress at the same time, there is a 

corresponding need to provide for communication with several spacecraft at any given time. 

NASA’s spacecraft must be tracked and controlled; the health, condition and safety of the 

spacecraft must be monitored; and the scientific data that is obtained must be transmitted to 

mission operators. Channels are needed for robust, low data rate communications designed for 

critical TT&C and, in the case of crewed spacecraft, for voice services. Still other channels are 

needed for high data rate communications for transmission of scientific or payload data. 

To satisfy its communications needs, NASA operates a sophisticated global infrastructure, 

consisting of several component networks: 

 The DSN is used to support scientific spacecraft; it provides coverage from LEO to the edge 

of the solar system. 

 The SN provides tracking and data relay for spacecraft, satellites, and expendable launch 

vehicles using space and ground segments. It includes the TDRS, which are communications 

satellites in geostationary orbit used to relay data from spacecraft to fixed ground locations. 

The satellite relays provide continuous global coverage of Earth orbits from equatorial to 

highly inclined orbits. 

Chapter 5 Purpose: To provide an overview of NASA spectrum utilization that conveys 

the diversity of its operations and associated spectrum requirements. 
29 

 The NEN consists of ground stations owned by NASA, commercial entities, and other partners 

that providing communications and tracking services to missions operating in the near earth 

region. Most of the EESS-related missions use this network. 

Figure 5.1: NASA Communications Networks 

In order to support the intermediate and long term goals of understanding the Earth, NASA has 

developed numerous radio sensors designed to fly onboard spacecraft. These sensors may be 

passive or active in operation. Passive sensors measure the natural emissions of the Earth’s and 

atmospheric constituents at particular frequencies or frequency ranges in order to provide a 

description of the Earth's environment. These sensors are particularly prone to RF interference 

from other emitters and, if possible, need exclusive allocations in bands of critical importance. 

Active sensors are spaceborne radars that can provide information on the geological structure of 

the Earth and the state of and movement of Earth’s oceans. These sensors use spectrum allocated 

to the EESS. 

In most cases, identification of RF spectrum support for Agency needs is focused on frequency 

bands currently allocated nationally and internationally for the particular radio service for which 

NASA requires support. This includes both space use (in spectrum allocated to space science 

services) and terrestrial use (in fixed and mobile service allocations). However, in some cases, 

particularly as new scientific, technological or commercial requirements emerge or as bands 

become congested, it may be necessary to consider implementing Agency operations elsewhere in 

the RF spectrum where appropriate service allocations do not currently exist. 
30 

5.2 Earth Science 

Earth Science research at 

NASA has turned space-based 

observing technology and 

scientific expertise to use for 

the study of our home planet. 

Planet Earth is an integrated 

system of land, ocean, 

atmosphere, ice, and biological 

processes. The lives of people 

everywhere on Earth are 

affected by environmental 

conditions of the land, the 

oceans, and the atmosphere. 

Spaceborne sensors are the 

only tools that can provide 

environmental data repetitively on a global scale. From the vantage point of space, we are 

beginning to understand how environmental processes work and how they interact. 

EESS sensors utilize several frequencies driven by the physics involved but observed everywhere 

on the Earth's surface or in its atmosphere (this is unlike the RAS, which, in the extreme, would 

like to observe the spectrum from direct current to gamma rays but only from a few geographical 

locations, e.g. an observatory on a mountain top). These EESS sensors allow global “pictures” to 

be taken of the Earth on a daily basis in a wide range of frequencies. Use of the passive and active 

microwave sensors removes the need for sunlight and permits penetration of clouds, thus providing 

nighttime as well as all-weather coverage. These sensors can measure: temperature, humidity, 

cloud, and trace gas profiles; surface soil moisture; ocean and estuarian salinity; sea-surface 

temperature; land-surface roughness and biomass; ocean surface wave height and sea state; and 

the moisture content and melt character of ice and snow. Snow and ice-covered areas and bodies 

of water can be mapped under all weather conditions and at various penetration depths. 

The passive observations of the EESS require significant bandwidth to achieve measurable signal 

levels. EESS passive observations can be divided into two categories, observations around specific 

absorption bands (at lower frequencies, primarily atmospheric water lines and oxygen lines) and 

measurements of geophysical parameters requiring simultaneous observations from many bands. 

Passive observations around the water lines yield the profile of water in the atmosphere as a 

function of altitude, while observations around the oxygen lines yield the temperature profile of 

the atmosphere. Although a single observation may not be critical in itself, when combined with 

other such observations they are used to produce modern weather forecasts. The forecasting 

programs constantly update and fine-tune the resulting forecasts by assimilating real-time, or near 

real-time data. Substantial improvements have been made in such forecasts by the addition of 

satellite microwave observations of the atmosphere, particularly in the southern hemisphere where 

other observations had been fewer and farther between. 
31 

Other passive observations yield geophysical parameters such as vegetation biomass, soil 

moisture, surface roughness, cloud liquid water, and integrated water content over the land and 

salinity, wind speed, sea surface temperature, water vapor, and liquid clouds over the oceans. 

However, these parameters frequently appear in combination with most, if not all, of the others. 

This situation requires multiple observations at different frequencies to resolve the individual 

components. Rarely is one parameter predominant and able to be measured with adequate 

accuracy using only one or two bands. 

Regulatory agencies have recognized the need for protecting passive bands. The ITU frequency 

allocation table states that no station shall be authorized to transmit in the following bands: 1400-

1427 MHz, 2690-2700 MHz, 10.68-10.7 GHz, 15.35-15.4 GHz, 23.6-24 GHz, 31.3-31.5 GHz, 

31.5-31.8 GHz (in Region 2), 50.2-50.4 GHz, 52.6-54.25 GHz, 86-92 GHz, 100-102 GHz, 109.5-

111.8 GHz, 114.25-116 GHz, 148.5-151.5 GHz, 164-167 GHz, 182-185 GHz, 190-191.8 GHz, 

200-209 GHz, 226-231.5 GHz, and 250-252 GHz. 

RFs are formally allocated up to 275 GHz. However, the ITU recognizes that some higher 

frequencies are of interest to the EESS, RAS, and SRS. Passive bands between 275 GHz and 1000 

GHz have been identified and are listed in the RR. The use by passive services in these bands does 

not preclude the use of active services, and all frequencies in the range 1000-3000 GHz may be 

used by both active and passive services. 

Active measurements take many forms. A Synthetic Aperture Radar (SAR) uses the Doppler shift 

in the return signal to substitute for one dimension of the antenna, and the full two-dimensional 

aperture is synthesized computationally. An SAR produces images of the rain and terrain below 

and to the side of the spacecraft, depending upon the frequency used. Lower frequencies (typically 

below 10 GHz) penetrate rain and vegetation, while higher frequencies are used to measure rain 

and cloud parameters. SAR images of the same terrain taken from two locations can be used to 

produce topographic maps. SAR images taken from the same location but at different times can 

be combined (as both the amplitude and phase of the return signal are recorded) to produce 

interferograms, which map the surface movement associated with earthquakes, landslides, and 

volcanoes. This technique, called interferometric SAR, can measure sub-centimeter ground 

movement at distances of over 700 kilometers. Another technique, called scatterometry, uses 

variations in the return signal as a function of azimuth to resolve the speed and direction of sea 

surface winds. Satellite-borne altimeters are used to monitor sea surface heights, which can be 

used to forecast upcoming El Niño/La Niña conditions. Precipitation radars (typically around 13 

GHz) determine the rainfall rate over the Earth's surface and the three-dimensional structure of the 

rainfall. Cloud profile radars (~94 GHz) measure the cloud reflectivity profile. 

In addition to their use of spectrum for sensors, the Earth science missions also use spectrum for 

tracking, guidance of spacecraft, monitoring of spacecraft “health”, and control of instrumentation. 

The data collected by sensors is transmitted by radio links to facilities on Earth, either directly or 

through relay satellites. The radio spectrum utilized for this purpose is primarily in the vicinity of 

2 GHz (S-band) for low-rate data and 7/8 GHz (X-band) for high-rate data. 

Recent missions contributing to Earth Science are the Orbiting Carbon Observatory-2 (OCO-2) 

and SMAP. OCO-2 is NASA’s first Earth remote sensing satellite dedicated to study atmospheric 
32 

carbon dioxide from Space. OCO-2 collects global measurements of atmospheric CO2 with the 

precision, resolution, and coverage needed to characterize its sources and will also be able to 

quantify CO2 variability over the seasonal cycles year after year. SMAP data have both high 

science value and high applications value. The accuracy, resolution, and global coverage of SMAP 

soil moisture and freeze/thaw measurements will be invaluable across many science and 

applications disciplines including hydrology, climate, carbon cycle, and the meteorological, 

environmental and ecology applications communities. Current climate models’ uncertainties 

result in disagreement on whether there will be more or less water regionally compared to today; 

however, SMAP data will enable climate models to be brought into agreement on future trends in 

water resource availability. SMAP contains both an active sensor SAR operating at 1.26 GHz and 

a passive sensor radiometer operating at 1.41 GHz. 

In addition, NASA provides complete satellites and their instruments to the US Geological Survey 

to monitor the Earth’s surface with their Land Remote Sensing Satellite series and to the NOAA 

to monitor weather with their geosynchronous satellites (GOES series) and low Earth orbiting 

series. These missions monitor the Earth’s environment for operational purposes, rather than the 

research orientation of NASA. 

5.3 Space Science 

NASA’s space science missions are intended to 

examine the mysteries of the universe from 

origins to destiny, to explore the solar system, to 

discover planets around other stars, to search for 

life beyond Earth and to chart the evolution of 

the universe and understand its galaxies, stars, 

planets, and life. Active and passive remote 

sensing of the Moon and other planetary bodies 

is performed in the SRS. NASA’s scientific 

investigation of the solar system is being 

accomplished mainly through the use of 

unmanned automated spacecraft. These 

spacecraft have created a virtual human presence 

in the solar system, exploring new territories and 

investigating the solar system in all its 

complexity. NASA has also sent probes into 

interstellar space, beginning a human presence 

even beyond the solar system. NASA is probing 

the universe to the beginning of time, looking 

ever deeper with increasingly capable telescopes. 

Space science missions require highly reliable 

communications, and in turn spectrum access, 

often over long periods of time and great distances. The large distances involved in deep-space 

research result in a need for high power transmitters and very sensitive receivers at Earth stations 

that communicate with the spacecraft. Spectrum to support deep space research specifically has 
33 

been allocated in S-band at 2110-2120 MHz (Earth-to-space) and 2290-2300 MHz (space-toEarth). Because many deep-space missions continue for periods of several years, and because 

there are usually several missions in progress at the same time, there is a corresponding need for 

communication with several spacecraft at any given time. Coverage of simultaneous missions 

requires nearly continuous usage of RF bands allocated for space research communication. 

Many are familiar with NASA’s space science efforts through images received from the Hubble 

Space Telescope. Hubble is the largest optical telescope to be placed in space to date, and is the 

first science mission designed to be repaired and upgraded while in orbit. Above the distortion of 

the atmosphere, far above rain clouds and light pollution, it has an unobstructed view of the 

universe. Scientists have used Hubble to observe the most distant stars and galaxies as well as the 

planets in our solar system. It has made more than one million observations since its mission 

began in 1990; and as of Hubble's 24th anniversary in April 2014, Hubble observations have 

produced more than 100 terabytes of data. Since January 2013, the Hubble has generated 844 

gigabytes of data per month. 

The James Webb Space Telescope, planned for later in the decade, will be the premier observatory 

of the next decade, serving thousands of astronomers worldwide. Webb will be located at 

the second Lagrange point, about a million miles from the Earth. It will study every phase in the 

history of our Universe, ranging from the first luminous glows after the Big Bang, to the formation 

of solar systems capable of supporting life on planets like Earth, to the evolution of our own Solar 

System. 

The Solar Dynamics Observatory (SDO) is taking a close look at the Sun, the source of all space 

weather. Space weather affects not only our lives here on Earth, but the Earth itself, and everything 

outside its atmosphere (astronauts and satellites out in space and even the other planets). SDO 

will help us understand where the Sun’s energy comes from, how the inside of the Sun works, and 

how energy is stored and released in the Sun’s atmosphere. SDO produces enough data to fill a 

single compact disc every 36 seconds. SDO has no recording system but sends all of its date, in 

real time, directly to its own ground station in New Mexico. 

 
34 

5.4 Human Space Exploration 

NASA seeks to open the 

frontiers of space by human 

exploration, enabling the 

development of operations in 

space and expanding the 

human experience into the far 

reaches of the solar system. In 

exploring space, NASA has 

brought together a wide range 

of technologies, machines and 

people in the development of 

such programs as the STS and 

the ISS. NASA now has even 

more ambitious goals in sight. 

NASA is developing the 

capabilities needed to send 

humans to an asteroid by 2025 

and Mars in the 2030s – goals 

outlined in the NASA Authorization Act of 2010 and in the US National Space Policy, also issued 

in 2010. A fleet of robotic spacecraft and rovers already are on and around Mars, paving the way 

for future human explorers. While robotic explorers have studied Mars for more than 40 years, 

NASA’s path for the human exploration of Mars begins in LEO aboard the ISS. Astronauts on the 

orbiting laboratory are helping to prove many of the technologies and communications systems 

needed for human missions to deep space, including Mars. 

NASA is building a new spacecraft that will usher in the new era of space exploration. The Orion 

spacecraft is designed to meet the evolving needs of our nation’s deep space exploration program 

for decades to come. It will be the safest, most advanced spacecraft ever built, and it will be 

flexible and capable enough to take astronauts to a variety of destinations. Orion will utilize 

advances in propulsion, communications, life support, structural design, navigation and power. Its 

unique life support, propulsion, thermal protection and avionics systems will enable extended 

duration deep space missions. With destinations including near-Earth asteroids, our own Moon, 

the moons of Mars and eventually Mars itself, Orion will carry astronauts into a new era of 

exploration. 

The next step will be to deep space, where NASA will send a robotic mission to capture and 

redirect an asteroid to orbit the moon. Astronauts aboard the Orion spacecraft will explore the 

asteroid in the 2020s, returning to Earth with samples. This experience in human spaceflight 

beyond LEO will help NASA test new systems and capabilities, such as Solar Electric Propulsion, 

which will be needed to send cargo as part of human missions to Mars. 

Beginning in 2017, NASA’s Space Launch System (SLS) rocket will enable “proving ground” 

missions to test new capabilities. Human missions to Mars will rely on Orion and an evolved 

version of SLS that will be the most powerful launch vehicle ever flown. SLS will be the most 
35 

powerful rocket in history and is designed to be flexible and evolvable, to meet a variety of crew 

and cargo mission needs. SLS will launch astronauts in the Agency’s Orion spacecraft on missions 

to an asteroid and eventually to Mars, while opening new possibilities for other payloads including 

robotic scientific missions to places like Mars, Saturn and Jupiter. 

As NASA sets its sights on exploring beyond LEO, the ability of the private sector to provide 

routine access to space and the ISS is of vital importance. NASA’s Commercial Orbital 

Transportation Services (COTS) program was the catalyst for this expanding new industry. Under 

COTS, NASA helped commercial partners develop and demonstrate their own cargo space 

transportation capabilities to serve the US government and other potential customers. Two 

companies, Space Exploration Technologies (SpaceX) and Orbital Alliant Techsystems (ATK) 

developed technologies and capabilities to complete orbital space flight demonstrations. The ISS 

Program has purchased cargo delivery services from both companies to resupply the space station 

through 2015. 

NASA’s Commercial Crew Program (CCP) was formed to facilitate the development of a US 

commercial crew space transportation capability with the goal of achieving safe, reliable and costeffective access to and from the International Space Station and LEO. CCP has invested in 

multiple American companies that are designing and developing transportation capabilities to and 

from LEO and the ISS. By supporting the development of human spaceflight capabilities, NASA 

is laying the foundation for future commercial transportation capabilities. After several rounds of 

development and certification, two contracts have been awarded, to Boeing and SpaceX, for 

commercially built and operated transportation systems, which will transport NASA crew to the 

ISS. 

All of these programs have required, and will continue to require, extremely complex and critical 

radio systems. These radio systems will require bands of frequencies spanning the spectrum from 

about 100 MHz up to more than 30 GHz. 

5.5 Aeronautics and Space Technology Development 

Another of NASA’s endeavors is to pioneer the 

identification, development, and verification of 

high-payoff aeronautics technologies. NASA is 

focused on developing technology solutions that 

will eliminate barriers to growth for the civil 

aviation system and provide a safe, efficient 

national aviation system. To these ends, it 

conducts testing in the areas of aviation, flight 

research, airframes, and aeropropulsion. NASA 

operates one-of-a-kind aircraft to support a wide 

variety of research missions. These “testbeds” 

provide platforms for aerodynamic system and 

propulsion research and testing, and for validation 

of sensors intended for use in space. NASA uses 

RF spectrum for the reception of data, including 
36 

video, from airborne vehicles and for telecommand of those vehicles. Vehicles include 

experimental aircraft, remotely piloted aircraft, and high altitude balloons. 

NASA requires access to the radio spectrum in order to conduct these tests of new technologies in 

aeronautics and space transportation. NASA flight test and research operations vary in both scope 

and time. Aircraft, which include models, may fly at altitudes from a few feet up to altitudes on 

the order of 5000 feet and ranges may extend from an immediate locale out to a range of several 

hundred miles. Missions might last from minutes, to hours or days, and their scheduling may be 

dependent upon competing missions at the test centers. 

In many cases, prototypes undergo various test and validation phases using conventional terrestrial 

spectrum allocations for mobile or point-to-point operations. For links between in-flight aircraft 

and ground systems, NASA requires access to spectrum allocations for aeronautical telemetry. 

The RF spectrum is used to provide real-time flight data information from test vehicles to the 

ground, real time video of cockpit or project information, and real time command and control of 

the vehicle, including flight termination. 

In addition to flight test and research operations for experimental aircraft, NASA also operates 

Unmanned Aeronautical Vehicles (UAVs) and scientific balloons. UAVs are used for the purpose 

of conducting airborne remote sensing and science observations. These operations might involve 

development and calibration of sensors, or collection of data to support NASA Earth science 

programs concerned with the measurement of environmental parameters. The primary objective 

of the NASA balloon programs is to provide high altitude platforms for scientific and technological 

investigations; they also provide a platform for the demonstration of promising new instrument 

and spacecraft technologies. NASA balloons will routinely fly above 100,000 feet. Balloon 

operations vary in their time and frequency of use. Shorter missions may last between two hours 

to three days and may occur 15 to 20 times per year; longer missions, lasting up to several weeks, 

may occur several times per year, while extended duration missions, up to 100 days, may also 

occur once or twice per year. 

NASA requires spectrum for links between aircraft and ground systems. This spectrum is used to 

provide real-time flight data information from test vehicles to the ground, real time video of cockpit 

or project information, and real time command and control of the vehicle, including flight 

termination. For its testing, NASA uses spectrum allocated for Aeronautical Telemetry Service in 

the L-Band at 1435-1525 MHz; S-Band at 2200-2300 MHz; Upper S-Band at 2310-2390 MHz; 

and C-Band at 4400-4940 MHz and 5925-6700 MHz. 

 
37 

Chapter 6 

6. National Spectrum Issues and NASA Equities 

Contention for spectrum is coming from both unlicensed and licensed wireless operations, which 

seek access to additional federal government bands to meet burgeoning consumer demand for 

broadband, including in federal bands used by NASA. 

Looking toward the future, the development and distribution of new wireless broadband products 

and services will accelerate, driven by consumer demand for ubiquitous access to communications 

and information. 

To address growing demands for spectrum, several domestic policy trends are coming together 

right now, including expanded use of sharing between different types of users (such as federal 

government and commercial). Policymakers and technology developers are also looking to both 

leverage the potential use of higher frequencies and to increase the efficiency of utilization in the 

most desirable spectrum below 3 GHz. Another issue is an increase in demand from the 

commercial sector for the use of the same frequencies and in the same geographies that are critical 

for NASA applications. Against this backdrop, policymakers are also increasingly interested in 

finding new ways to create incentives for more efficient federal Agency spectrum use, including 

potential use of new economic tools such as market-based spectrum user fees or incentive auctions 

of Federal spectrum bands. Collectively, such issues are affecting NASA’s existing and planned 

operations throughout the radio spectrum. 

6.1 Mobile Broadband 

Key drivers of mobile broadband growth include the development of smartphones and other 

mobile computing devices, the emergence of broad new classes of connected devices (the Internet 

of things) and the rollout of 4G wireless technologies such as LTE. According to the Cisco Visual 

Networking Index, worldwide mobile data traffic is expected to reach 15.9 exabytesi

 per month by 

2018.ii An increase in mobile broadband use raises demand for other wireless services, such as 

point-to-point wireless services for backhaul and unlicensed Wi-Fi networks, to enhance the 

overall delivery of broadband to consumers. 

Unlicensed services such as Wi-Fi are important complements to licensed mobile networks and to 

wireline networks. Wi-Fi provides wireless Internet access for personal computers and handheld 

devices and is also used by businesses to link computer-based communications within a local area. 

Many wireless devices that operate on licensed frequencies can also use the unlicensed frequencies 

set aside for Wi-Fi. Most smartphones and tablets available today feature Wi-Fi, and users take 

advantage of this capability inside homes or businesses where high-speed broadband connectivity 

is available. 

Chapter 6 Purpose: To provide an overview of current domestic spectrum issues and their 

relationship to NASA spectrum utilization. 
38 

Several portions of the radio spectrum that are under consideration for future wireless industry use 

for mobile broadband – as a result of the above-mentioned drivers – carry potential implications 

for NASA equities. One example is the so-called S-band (2025-2110 MHz and 2200-2290 MHz), 

in which the Agency has vital command and control uplinks and important data return downlinks 

as well as links to its TDRSS relay satellite system. Another is the 5 GHz band (5150-5925 MHz), 

in which the Agency operates sensors that collect important data on the Earth’s environment. 

6.2 National Broadband Plan 

In 2010, the FCC released a National Broadband Plan that called for making additional spectrum 

available for wireless broadband use – 500 MHz – by 2020. The National Broadband Plan made 

several recommendations for obtaining the additional spectrum for wireless broadband use. 

For example, the plan recommended that the FCC create a new way of auctioning certain 

commercial spectrum bands, based on providing a portion of auction revenues to incumbents as 

an incentive for giving up spectrum entirely or giving up a portion of licensed channels and sharing 

remaining capacity. 

The plan provided details for how the FCC would carry out these voluntary incentive auctions, 

which will be the first of their kind in the world, starting with broadcast television bands in the 

highly valued 600 MHz range (there has also been interest, including in Congress, for applying 

this nascent auction model to federal bands). The plan recommended that the FCC should 

accelerate terrestrial deployment in 90 MHz of MSS spectrum by building on past efforts to enable 

terrestrial deployment in MSS bands, which originally had been restricted for satellite-based uses. 

A June 2010 Executive Memorandum adopted the same 500 MHz goal by 2020 as the Broadband 

Plan. The President directed the Secretary of Commerce, through NTIA, to collaborate with the 

FCC to produce a ten-year plan and timetable for making available 500 MHz of federal and nonfederal spectrum suitable for wireless broadband use on a shared or exclusive basis. A follow-up 

memorandum in 2013 focused on expediting progress toward making more spectrum available for 

broadband, including as part of new sharing efforts. 

6.2.1 Evolving Auction Policy 

Most importantly for federal agencies, the plan said that the FCC should make up to 60 megahertz 

available by auctioning AWS bands, including, if possible, 20 MHz from federal allocations. This 

recommendation expedited momentum toward repurposing the federal spectrum band of 1755-

1780 MHz, in which NASA has some user equities paired with the commercial band of 2155-2175 

MHz. Potential synergies existed between this AWS-3 band and spectrum allocated to federal use 

at 1755-1780 MHz. 

Subsequent to the release of the FCC’s plan, Congressional action was taken in the form of the 

spectrum provisions in the Middle Class Tax Relief and Job Creation Act of 2012. The spectrum 

provisions of this legislation, known as the Spectrum Act, gave the FCC incentive auction authority 

and set a series of auction deadlines in order to meet deficit reduction goals and to provide funding 

for a planned national first responder network, FirstNet. The 1755-1780 MHz band was not among 
39 

those included in the 65 megahertz required to be auctioned, but the paired commercial band, 2155-

2180 MHz was, providing momentum for an auction of both bands. 

In April of 2014, the FCC adopted rules governing use of AWS-3 spectrum in the 1695-1710 MHz, 

1755-1780 MHz, and 2155-2180 MHz bands. The 1755-1780 MHz band was made available on 

a shared basis with a limited number of federal incumbents indefinitely, while most of the federal 

systems will over time relocate out of the band. As part of new requirements under the Spectrum 

Act, NASA successfully submitted a transition plan to a new Technical Review Panel for its 

operations that will relocate from this spectrum on a reimbursed basis as a portion of auction 

revenue. The Commission also adopted rules to allocate and license the 1695-1710 MHz band for 

uplink/mobile operations on an unpaired shared basis with incumbent federal meteorologicalsatellite data users. Upon its conclusion in January 2015, the AWS-3 auction had generated the 

highest auction revenue in FCC history, about $45 billion. This result is leading policy makers to 

consider its implications for future spectrum allocations. 

 

Potential Reallocation – Case in Point 

Since 2010, the NTIA, in collaboration with the FCC and other federal agencies, has prepared 

a plan and timetable that identified over 2,200 MHz of federal and non-federal spectrum that 

could be evaluated for potential opportunities for wireless broadband use. Among the bands 

identified were those containing NASA equities, including 2200-2290 MHz. As of the start 

of 2015, NTIA has identified more than 405 MHz of federal spectrum as available or 

potentially available for broadband use. 

NTIA has described a methodology for reviewing additional federal spectrum bands to reach 

the 500 MHz goal. As part of these deliberations, one band mentioned for reallocation was 

2200-2290 MHz, which is the “backbone spectrum band” for NASA and is critical to the 

agency. This spectrum provides ideal propagation characteristics for reliable communications 

with spacecraft; it permits use of omni-directional spacecraft antennae for emergency/allweather situations. Many of the world’s space agencies also operate or plan communications 

networks in 2 GHz; and efforts are underway toward interoperability, that would permit 

resource sharing and cross-support. NTIA and the ITU-R have documented the results of 

studies that show that it is not feasible to share between the space science services and high 

density mobile systems. 

If this spectrum were to be re-allocated in the US, existing and planned spacecraft would lose 

the ability to communicate data or would face costly redesign. Existing communications 

networks would face re-fitting into other bands, if spectrum were even available. NASA 

would become isolated from other space agencies, and the US would lose benefits of 

international harmonization, including potential interoperability. 
40 

6.3 Spectrum Sharing

Spectrum sharing among federal agencies, including NASA, is already widely practiced to gain 

efficiencies from crowded federal bands. New sharing considerations between federal and nonfederal bands marks a point of departure and large-scale sharing between government incumbents 

and new commercial entrants is largely untested in many bands. Policymakers are assessing how 

bands such as 3.55-3.65 GHz and frequencies in the 5 GHz range can be shared between federal 

users and new commercial wireless applications. Although the spectrum used by NASA has not 

been affected thus far, the methodologies being developed could be considered by policymakers 

in the future for imposition in frequencies of interest to NASA. 

In July 2012, PCAST (see Chapter 1) concluded that the traditional method for accommodating 

new services by clearing and reallocating portions of federal spectrum is not a sustainable model 

for national spectrum policy because it is too costly and takes too much time. 

In part, PCAST recommended that the federal government should share underutilized federal 

spectrum to the maximum extent possible and identify 1,000 MHz of federal spectrum for shared 

use. It also recommended that policymakers authorize and implement, in collaboration with 

industry partners, a federal Spectrum Access System (SAS), which would serve as an information 

and control clearinghouse for the band-by-band registrations and conditions of use that would 

apply to all users with access to each shared federal band under its jurisdiction. 

Under PCAST’s vision, the federal SAS would be designed to address the availability of both 

geolocation databases operating almost in real time along with cognitive radio capabilities (i.e., 

sensing, dynamic spectrum access), working separately or in combination, make opportunistic 

access feasible on a band-by-band basis, subject to conditions that would be tailored to avoid 

harmful interference to licensed operations. While tech players such as Google have been 

advocates for this solution, it has not yet been deployed and it is not yet clear how a database would 

address federal government incumbent system (i.e., SAS) security concerns. 

PCAST recommended that the shared spectrum be organized into three tiers: 

 The first tier would consist of incumbent federal users, who would be entitled to full 

protection for their operations within their deployed areas. 

 The second tier would consist of users that would receive short-term priority authorizations 

to operate within designated geographic areas. Secondary users would receive protection 

from interference from third tier users but would be required to avoid interference with and 

accept interference from the federal primary users. 

 Third tier users (General Authorized Access [GAA]) would be entitled to use the spectrum 

on an opportunistic basis and would not be entitled to interference protection. 

6.3.1 Sharing in 3.5 GHz 

Prior to new sharing rules adopted for 3.5 GHz by the FCC in April 2015, NTIA had identified 

this spectrum for potential shared federal and non-federal broadband use (NASA does not have 
41 

operations in this band but has a potential interest in how such a framework may be applied to 

other swathes of Federal spectrum in the future). 

 

Incumbent uses in the band include high powered Department of Defense (DoD) radars as well as 

non-federal Fixed Satellite Service (FSS) earth stations used for receive-only, space-to-earth 

operations and feeder links. In the adjacent band below 3550 MHz there are high-powered ground 

and airborne military radars. NTIA initially recommended, based on the commercial wireless 

broadband technology that it assessed, that new commercial uses of the band should occur outside 

of large “exclusion zones,” which would be designed to protect government operations. Tech 

companies had a particular interest in finding more flexible sharing solutions for commercial 

access to this spectrum because they perceived the exclusion zones as being too large  and 

covering too many critical markets  to facilitate broadband operations. 

The final rules for the band, for a so-called Citizens Broadband Radio Service, include a threetiered spectrum authorization framework for Incumbent, Priority, and GAA users. The FCC’s 

order creates a roadmap to allow commercial operations in the band on a shared basis by leveraging 

spectrum sensing technologies. In an initial phase, coastal protections will be 77 percent smaller 

than previously anticipated to protect military users. The FCC said this reduction reflects extensive 

cooperative work between the FCC, NTIA and DoD. For the incumbent tier, a two-phase approach 

will reduce the exclusion zones. The first phase will feature the exclusion zones, which are smaller 

than initially proposed. The second will feature an environmental sensor network to enable devices 

to operate in the exclusion zones when incumbents are not operating. 

Besides the incumbent tier, rules for the GAA will let any user with a certified device to operate 

without seeking further FCC approval, similar to how unlicensed uses can function, except that 

they will need to register. Under the Priority Access tier, short-term priority rights to a portion of 

the band will be available through future spectrum auctions. One or more SASs, operated by 

commercial entities, will allow coexistence among the different user tiers, similar to what PCAST 

envisioned. 

6.3.2 Sharing in the 5 GHz Band 

Many of the spectrum issues facing NASA are embodied in current deliberations regarding future 

use of spectrum in the 5.150-5.975 GHz portion of the radio spectrum. Broadband proponents 

seek increased access to the 5 GHz bands for unlicensed use. Policymakers have endorsed sharing 

concepts and may consider applying methods being developed at 3.5 GHz. In the meantime, 

NASA and other agencies use the spectrum for important services, which could be affected by the 

new entrants. 

The Commission first made available 300 megahertz of spectrum in the frequency bands 5.15-5.35 

GHz and 5.725-5.825 GHz bands for unlicensed intentional radiators, known as Unlicensed 

National Information Infrastructure (U-NII) devices in 1997. In 2003, the Commission made an 

additional 255 megahertz of spectrum available in the 5.47-5.725 GHz band for U-NII devices. 

The 5.35- 5.47 GHz band is allocated on a primary basis to the EESS Research, and Radiolocation 

Services for federal operations and on a secondary basis for non-federal operations. NASA uses 
42 

this band for test and launch range instrumentation radars to track rockets, missiles, satellites, 

launch vehicles, and other targets. NASA operates a limited number of Unmanned Aircraft 

systems in the band that are used for downlink transmissions of data to ground control receivers. 

SAR systems in the 5.35-5.47 GHz band perform space-based observations and measurements of 

surface topography, soil moisture, and sea surface height. These wideband SARs provide the 

resolution necessary for applications such as high-resolution surface mapping.iii NASA, in joint 

ventures with the French agency, Centre National d’Etudes Spatiales, also operates a space-based 

altimeter system in the 5.14-5.46 GHz band to obtain measurements of the Earth’s ocean surface 

height. 

As required by the Spectrum Act, NTIA has published a report, prepared in consultation with DoD 

and other affected federal agencies, evaluating spectrum sharing technologies and the risk to 

federal users of unlicensed operations in the band. In 2013, the FCC issued a Notice of Proposed 

Rulemaking (NPRM) seeking comment on making available an additional 195 megahertz of 

spectrum in the 5.35-5.47 GHz and 5.85-5.925 GHz bands for unlicensed broadband use. The 

FCC has not yet adopted final rules. 

6.4 “New Space” Issues

Beyond the mobile broadband policy debate, NASA’s spectrum use is affected by the needs of the 

growing commercial space sector. This sector has grown beyond the provision of basic 

communications and broadcasting services through satellites, to the provision of Earth resources 

information and the development of envisioned markets such as space tourism. The private sector 

is developing launch vehicles and facilities, as well as payloads, which require access to spectrum 

resources. NASA is working with federal regulators to assess ways that federal spectrum 

traditionally used by NASA for its own operations can be made available, when needed, by private 

sector stakeholders for commercial launches and operations in space. 

Under the National Aeronautics and Space Act of 1958, NASA has the responsibility to encourage, 

to the maximum extent possible, the commercial use of space. In June 2010, the President 

announced a National Space Policy, which expresses the President’s direction for the Nation’s 

space activities.iv Most, but not all, of the spectrum allocated to the Space Research and Space 

Operations services in the US has been designated for federal-only use. Since federal agencies 

have been the primary users of this spectrum, historically there has been no incentive to establish 

the allocations on a shared basis in the US frequency allocation tables. However concern is now 

being raised by commercial providers over their lack of access to currently allocated space services 

spectrum. 

The end of NASA’s space shuttle program has led to the development of a new era of cargo 

delivery and manned space travel initiatives that promise to continue the US legacy of exploration, 

education and discovery. Several private companies have been selected to take cargo and, in the 

future, people into space to support the ISS and other NASA initiatives. SpaceX and Orbital ATK 

have recently accomplished successful missions to the space station. Other companies are 

developing the capability to take tourists on suborbital forays into space. To support the nascent 

private launch industry, a number of non-federal government owned space ports have been 

established. 
43 

Commercial users currently utilize two avenues to secure FCC authorization of their proposed use 

of space services spectrum: 

 They may pursue a license, including a STA, under the Commission’s rules and regulations 

covering the commercial Satellite Communications Services. This is a less certain form of 

spectrum access for commercial providers, since STAs are granted with a fixed expiration 

date, usually six months. v

 Commercial users may also pursue an Experimental Radio Service license (or an STA) under 

the rules governing the Experimental Radio Service. This service is intended to provide for 

experimental uses of radio frequencies and development of techniques and systems that are 

not otherwise permitted under existing service rules. 

In May 2013, the FCC released an NPRM/Notice of Inquiry (NOI), which addresses the spectrum 

needs of the commercial space launch industry. The FCC proposed several alternatives for 

providing spectrum for use during commercial space launches, thereby providing launch vehicles 

with interference protection. During launches by federal agencies, spectrum in the 420-430 MHz, 

2200-2290 MHz, and 5650-5925 MHz bands has been typically used to send a self-destruct signal 

to the launch vehicle (if needed) and information from the launch vehicle to controllers on ground, 

as well as to track the launch vehicle by radar. The Commission is considering how to modify the 

allocations to allow non-federal use of these bands in order to provide commercial entities access 

to spectrum. In the NOI, the FCC sought comment broadly on the future spectrum needs of the 

commercial space sector. It asked about the communication needs of suborbital space flights and 

commercial space stations, whether access to other frequency bands will be required, and whether 

amendments to the Commission’s rules will be needed. 

The federal bands under consideration for more predictable commercial space industry access for 

launches are already used by government agencies, including the key NASA band of 2200-2290 

MHz. Among issues of interest to NASA are whether there is sufficient spectrum available in this 

band for use during commercial launches and whether use of this band could sustain the anticipated 

growth of the commercial launch sector and if additional federal bands will be studied for other 

aspects of commercial space services, including re-entry or the “on orbit” phase of a mission that 

would require changes in allocations to Federal spectrum. 

 
44 

6.5 GPS Issues 

New wireless broadband uses that are entering 

spectrum bands adjacent to current NASA operations 

may impact Agency capabilities and require an 

adjacent band compatibility analysis to ensure that 

NASA missions do not encounter harmful 

interference and can continue without interruption. 

One example of this involves GPS capabilities on 

which NASA relies and which faces greater 

challenges with regard to the increased potential for 

harmful interference as new spectrum “neighbors” 

seek access to adjacent or nearby bands. GPS service 

is provided in the frequency band, 1559-1610 MHz. 

In the era of advanced wireless communications, 

new technology capabilities have created challenges 

for the continued operation of GPS without harmful 

interference. In 2002, for example, after a protracted regulatory proceeding, the FCC approved 

new rules for ultra-wideband, which is a technology that spreads a low-level signal across a very 

wide swath of spectrum. The final rules included provisions to protect GPS systems, however, 

during the development of the rules, the potential threat to GPS was a critical part of the policy 

debate. 

More recently, concerns over how to protect GPS have been sparked by flexibility for terrestrial 

operations sought by MSS licensee, LightSquared, using the bands allocated for this service at 

1525-1544 MHz and 1545-1559 MHz downlink and 1626.5-1645.5 MHz and 1646.5-1660.5 MHz 

uplink. LightSquared also has an authorization to use Ancillary Terrestrial Component (ATC) in 

the same frequency bands. ATC facilities are intended to provide voice and data communication 

for users equipped with dual-mode MSS/ATC devices; when MSS/ATC operation was first 

considered by the FCC, it was expected the number of ATC devices would be small. 

 LightSquared’s business plan called for utilizing this ATC authority to develop a 

nationwide terrestrial network, and to sell wholesale access to its network’s infrastructure. 

In January 2011, the FCC granted LightSquared a waiver of the Commission’s rules, which 

allowed LightSquared and its wholesale customers to offer terrestrial-only devices rather 

than having to incorporate both the satellite and terrestrial services. 

 Companies that provide global positioning systems and the United States Air Force, which 

maintains and operates the space and control segments of the GPS system, opposed the 

FCC waiver, because of concerns that LightSquared’s service might interfere with GPS 

service. Tens of thousands of base stations transmitting in the satellite-to-earth part of the 

MSS spectrum closest to the GPS spectrum raised the possibility that the high power 

terrestrial signals would interfere with far weaker GPS signals coming from space.

In April 2011, responding to concerns raised by the US GPS Industry Council and NTIA about 

LightSquared’s planned operations, the FCC stated that LightSquared could not commence 

Figure 6.1: The GPS Constellation flies 

in medium Earth orbit at an altitude of 

20,200 km (12,550 miles) 
45 

offering a commercial terrestrial service until the FCC had concluded that the concerns about 

harmful interference were resolved. The FCC stated that responsibility lies also with incumbent 

users, who should use receivers that reasonably discriminate against reception of signals outside 

their allocated spectrum. 

NASA has a number of GPS-dependent applications, which could be vulnerable to interference 

from the network as originally proposed by LightSquared. Affected systems could include groundbased, airborne, and space-based receivers used to support activities such as: Earth science 

research; weather forecasting; disaster monitoring; ground-truth calibration of instruments on 

orbit; precision navigation for aircraft and spacecraft; and search and rescue efforts. Research into 

development of future aeronautical applications might be affected, as well. 

In September 2012, LightSquared submitted applications to modify its licenses as part of an 

alternative proposal, which it said would provide a comprehensive solution to the issues that had 

precluded the deployment of its terrestrial wireless network. Lightsquared’s proposal include a 

spectrum swap to replace its terrestrial downlinks in 1545-1555 MHz and, instead, conduct them 

at 1670-1680 MHz. 

The FCC has not yet made final decisions on LightSquared requests for regulatory relief. To date, 

the LightSquared proceedings underscore the new challenges that policymakers and incumbent 

government operations face in balancing concerns about protecting mission critical Federal 

operations from interference and providing capacity for new broadband services. 

i

 One exabyte is one quintillion bytes, a billion gigabytes, or 1018 bytes. ii See Cisco Visual Networking Index, available at http://www.cisco.com/c/en/us/solutions/service-provider/visualnetworking-index-vni/index.html. 

iii Canada operates an Earth exploration-satellite, known as RADARSAT, in the 5.35-5.47 GHz band to provide 

mission critical data in support of national security, public safety, law enforcement, and civilian applications in 

Canada and the United States. For example, the United States Coast Guard International Ice Patrol uses 

RADARSAT data to detect and track icebergs. 

iv One of the principles in this Policy is that a robust and competitive commercial space sector is vital to continued 

progress in space. It states that the US is committed to encouraging and facilitating the growth of a US commercial 

space sector that supports US needs, is globally competitive, and advances US leadership in the generation of new 

markets and innovation-driven entrepreneurship. 

v In the case of contemplated new space services, for which there are no current applicable rules, the Commission 

has traditionally granted operating authority on an ad-hoc, case-by-case, basis until it has obtained sufficient 

experience and information to proceed to a formal rulemaking process.

                                                            
46 

Chapter 7 

7. Conclusion

Because nearly every endeavor that NASA undertakes requires communications or data transfer 

via the electromagnetic spectrum, the Agency remains committed to meeting the spectrum access 

needs of its global missions and activities. The electromagnetic spectrum environment in which 

NASA operates is constantly evolving, driven by both its own operating requirements and the 

rapidly escalating demands of the commercial wireless broadband sector for access to this limited 

resource. 

The spectrum management environment – driven by advanced technology capabilities, evolving 

policy frameworks and emerging operating requirements – poses both opportunities and challenges 

for NASA spectrum equities. With regard to challenges, national policymakers in the US have 

referred to the spectrum capacity crunch, with several bands that are under study for future wireless 

industry use carrying potential implications for NASA equities. These dynamic tensions between 

public sector and private sector spectrum access for existing and planned operations are playing 

out internationally, as well. At the ITU, this is occurring most visibly in the WRC arena and 

beyond, as the ITU-R works to finalize its vision of the connected future via planning efforts for 

5G. 

New sources of congestion and contention in spectrum bands used by NASA to carry out vital 

space missions are coming not just from the consumer wireless broadband sector but also from the 

commercial space sector, which is developing launch vehicles and facilities, as well as payloads, 

which require access to spectrum resources. 

Simply put, challenges and opportunities in this complex electromagnetic spectrum environment 

are redefining how NASA carries out its roles as a proactive spectrum steward. As part of critical 

international deliberations, including most notably those that unfold at WRCs, NASA remains ever 

vigilant to protect existing spectrum provisions from proposals that could affect its existing and 

planned operations. 

Increasingly, challenges and opportunities are intertwined. For example, NASA is working with 

federal regulators to assess ways that federal spectrum traditionally used by NASA for its own 

operations can be made available, when necessary, by private sector stakeholders for commercial 

launches and operations in space. On the one hand, NASA has statutorily mandated roles and 

responsibilities to encourage, to the maximum extent possible, the commercial use of space. At 

the same time, NASA is actively engaged in ensuring that spectrum access will be available when 

and where needed to support communications services essential to the operations of all NASA 

space flight missions. 

An increased focus by policymakers on spectrum sharing also presents both a challenge and an 

opportunity for NASA. The challenge is that a new range of bands that are critical to NASA 

mission requirements remain under scrutiny for potential mobile broadband access, including on 

a shared basis. The opportunity is that shared access, if the rules of the road are balanced to protect 
47 

NASA’s current and future user requirements, can provide new opportunities for meeting the needs 

of both private sector and public sector users. 

 
48 

Attachment A - Process for Spectrum Authorization 

All NASA missions requiring the use of the electromagnetic spectrum for communications 

transmission or reception (or both) or for sensor operations should follow the basic process 

outlined below. 

Per NPD 2570.5 and NPR 2570.1, it is NASA policy that any NASA system that requires the use 

of the electromagnetic spectrum for transmission, reception, or both shall follow the US spectrum 

regulatory rules and processes. The Spectrum Policy and Planning Division recently updated NPR 

2570.1, and all NASA programs and projects should obtain and review the latest version (NPR 

2570.1C, 22 Sep 2014). NPD 2570.5 and NPR 2570.1 provide detailed information that applies to 

all NASA science, technology, and exploration spaceflight programs/projects, both human-crewed 

and robotic. 

For guidance, NASA spaceflight projects that require the use of the electromagnetic spectrum for 

transmission, reception, or both should consider the following: 

 Frequency bands allocated to the science servicesi are appropriate, from a regulatory 

perspective, for spaceflight nominal operations, critical events, contingency operations, 

and emergency applications. For all spaceflight trajectories and distances from Earth (e.g. 

low-Earth, Lunar, or Mars missions), the frequency selection should be based on program 

requirements and considerations, as well as spectrum regulations. 

 From the NASA's Spectrum Policy and Planning Division's perspective, there is no 

preference to any of the science service allocated bands for routine and emergency 

applications of human-crewed or robotic missions. 

 All NASA spaceflight missions, regardless of size, to include small satellite systems, shall 

comply with United States spectrum regulatory rules and processes. All missions, 

including those sponsored by NASA via contract or grant to non-NASA entities, shall be 

coordinated with the relevant Center Spectrum Manager. 

 Center Spectrum Managers shall ensure that all missions comply with US spectrum 

regulatory rules and processes, to include hosted payload services. 

As noted in NPD 2570.5 and NPR 2570.1, all NASA program spectrum-related decisions and 

processes shall be coordinated with the Center Spectrum Managers and the NASA Spectrum Plans 

and Policy Division.

 

                                                            

i

 For example, one such science service, the Space Research Service (SRS), includes a number of bands useful for 

space communications including, but not limited to: 2025-2120 MHz, 2200-2300 MHz, 7145-7235 MHz, 8400-8500 

MHz, 25.5-27.0 GHz, 31.8-32.3 GHz, 34.2-34.7 GHz, etc. Specific constraints (e.g., Earth-to-space, space-to-Earth, 

use beyond 2M km (deep space), power flux density limits, etc.) may apply depending on the frequency band. 

NASA Center Spectrum Managers, as per NPD 2570.5 and NPR 2570.1, can assist in identifying these constraints. 
49 

Attachment B - NASA WRC-15 Objectives and Results 

NASA was successful at WRC-12 in getting several items added to the WRC-15 agenda: (1) An 

EESS uplink allocation in the 7-8 GHz range; (2) Review of current limits on the use of the 410-

420 MHz band for SRS operations; (3) An expansion of 600 megahertz around 9.5 GHz to support 

EESS (active) operations; and (4) Consideration of nanosat/picosat regulatory issues. 

Band Type Use NASA Recommendations 

7-8 GHz EESS uplink -EESS (space-to-Earth) allocation in 

the frequency band 8025-8400 MHz; 

terrestrial allocations to FS and MS in 

this range 

-2025-2110 MHz uplink band is 

crowded and many new satellite 

networks are anticipated 

Sharing with other services shown to 

be possible; provide primary 

allocation in the 7190-7250 MHz to 

alleviate growing congestion at 2025-

2110 MHz 

410-420 MHz SRS Astronaut EVA in the immediate 

vicinity of the ISS 

Remove five km distance limitation to 

permit proximity operations by 

visiting vehicles 

9.5 GHz EESS Active sensors (SARs) in 9300-9900 

MHz 

Expand by 600 MHz at 9900-10500 

MHz with appropriate provisions to 

protect incumbent services in order to 

enable higher resolution by next 

generation SAR sensors 

Table B1: NASA WRC-15 Spectrum Objectives 

B1 EESS Uplink at 7-8 GHz 

A sizable number of future EESS missions will require large data transmissions to spacecraft for 

operations plans and dynamic spacecraft software modifications. These requirements cannot be 

accommodated in the existing EESS uplink; 1,000 satellite networks have been filed with the ITU 

and many new are expected, including many microsatellites, nanosatellites and picosatellites. It 

will become extremely difficult, if not impossible, to coordinate the satellite networks’ spectrum 

requirements within the 2025-2110 MHz band. 

The EESS (Earth-to-space) allocation in the 7-8 GHz frequency range would help alleviate 

constraints in the 2025-2110 MHz band, sharing studies between EESS and other services in the 

7-8 GHz frequency range showed that sharing would be feasible in the 7190-7250 MHz band. As 

a result, WRC-15 established a new primary allocation to the EESS (Earth-to-space) in the 7190-

7250 MHz band, with conditions that ensure the protection of currently allocated services. 

B2 SRS at 410-420 MHz 

The 410-420 MHz band is used today for astronaut Extra Vehicular Activities communications in 

the immediate vicinity of the ISS. This band would be advantageous for proximity operations of 

ISS visiting vehicles. The band currently has power (Power Flux Density [PFD]) and distance 

limitations (5 km), agreed at WRC 1992. NASA proposed to modify the regulations to remove 
50 

the five km limit, while the PFD limits are sufficient to protect the terrestrial and mobile services 

in the band. WRC-15 agreed to the removal of the distance limitation. 

B3 EESS Expansion at 9.5 GHz 

WRC-15 considered an expansion to the EESS (active), by 600 MHz, to the 9300-9900 MHz band 

within the 8700-9300 MHz and 9900-10500 MHz frequency ranges. The expansion would enable 

higher image resolutions of less than 30 cm for next generation SAR sensors. 

NASA supported an extension of the current allocation to include the 9300-9900 MHz band. 

Currently, the US supports a primary allocation to EESS in the 9900-10500 MHz band, with 

appropriate provisions to ensure the protection of the incumbent services. Agreement was reached 

at WRC-15 on an EESS (active) extension in the bands 9200-9300 MHz and 9900-10400 MHz on 

a primary basis with provisions protecting incumbent services. However agreement under RR 9.21 

is required for operation in Algeria, Saudi Arabia, Bahrain, Egypt, Indonesia, Iran, Lebanon and 

Tunisia. 

B4 Regulations for Nanosatellites and Picosatellites 

WRC-15 considered regulatory aspects for nanosatellites and picosatellites. WRC-12 invited the 

ITU-R to examine the procedures for notifying space networks and to consider possible 

modifications to enable the deployment and operation of nanosatellites and picosatellites, while 

taking into account the short development time, short mission time and unique orbital 

characteristics of these types of satellites. 

Many of these satellites are launched for scientific, experimental or educational purposes, 

sometimes in the form of constellations, but there is a growing interest for commercial nonscientific applications. 

Consideration of this AI took into account the comparatively short development time and the 

potential lack of advance knowledge of certain operational parameters. It was also recognized that 

there is a need to educate the operators of these satellites regarding their regulatory obligations for 

filing with the ITU and, in some cases, coordinating operations internationally. 

WRC-15 concluded that frequency bands should align with their associated applications. The 

unique physical characteristics of these satellites are largely irrelevant to spectrum management 

and these satellites should be treated in the same manner as any other satellite technology. 

However, WRC-15 recognized that the time frames associated with the development and 

operations of these satellites, as well as the lack of advance knowledge of certain orbital 

parameters, can make the existing satellite filing procedures difficult. Any changes to the filing 

procedures in the RR will be considered under a standing WRC AI, which considers satellite 

coordination and registering procedures. 

 
51 

B5 Other WRC Items 

While NASA must be vigilant to protect all existing spectrum provisions from proposals that could 

affect its operations, there were several specific items of concern. These were: (1) Spectrum 

allocations for mobile broadband/IMT; (2) MSS uplink and downlink allocations in the 22-26 GHz 

band; and (3) MMSS uplinks in the 8025-8400 MHz band (see Table 7.2).

Bandwidth Type Use Study Results 

1400-1427 MHz EESS (Passive) Critical passive band for Earth 

observing Satellites 

A relevant combination of channel 

arrangements, guard bands and/or 

improved filters and other measures 

would be needed to allow the design 

of mobile systems in adjacent bands 

that are compliant with the specified 

OOBE values. 

2025-2110 MHz

2200-2290 MHz

SRS Provides vital command and control 

uplinks and important data return 

downlinks as well as links to 

NASA’s TDRS system. 

Sharing is not feasible between IMT 

systems and the forward and return 

(space-to-space) links of incumbent 

data relay satellites operating in 

these frequency bands. 

5350-5470 MHz EESS (active) Active Earth observing systems 

include SARs and altimeters 

Given assumed RLAN parameters, 

studies were made under the general 

assumption that the RLANs would 

be limited to indoor use only. 

Sharing between RLANs and the 

EESS (active) systems in this band 

would not be feasible. 

22-26 GHz MMS NASA uses SRS (Earth-to-space) 

band 22.55-23.15 GHz and 

EESS/SRS (space-to-Earth) band 

25.5-27.0 GHz; the Inter-satellite 

bands 22.55-23.55 GHz and 25.25-

27.5 GHz; EESS (passive) band 

23.6-24 GHz as well as 22.21-22.5 

GHz. 

Any mobile satellite services will be 

impacted planned NASA use of 

these bands. 

7-8 GHz MMSS Space science data downloads occur 

at 8025-8400 MHz EESS (space-toEarth) and 8400-8450 MHz SRS 

(space-to-Earth) (deep space). 

Ship operating in the vicinity of 

Earth stations near coasts could 

cause interference; enforcement of 

large exclusion zones would not be 

feasible in practice and interference 

would be difficult to track due to the 

mobile nature of the ships. 

Table B2: NASA WRC-15 Spectrum Concerns 

B5.1 Mobile Broadband/IMT 

Mobile communications, including mobile broadband communications contribute positively to the 

economic and social developments of both developed and developing countries. Many 

administrations are investigating a wide range of applications and systems to bridge the digital 

divide using IMT and other terrestrial mobile broadband applications. 
52 

The ITU is working towards realizing the future vision of mobile broadband communications. In 

early 2012, the ITU-R embarked on a program to develop “IMT for 2020 and beyond”; and it has 

described a timeline towards “IMT-2020”. In 2015, the ITU-R finalized its vision of the “5G” 

mobile broadband connected society. This view of the horizon for the future of mobile technology 

was considered at WRC-15, where deliberations on additional spectrum took place in support of 

the future growth of IMT. In the next phase, in the 2016-2017 timeframe, the ITU-R expects that 

its Working Party 5D will define in detail the performance requirements, evaluation criteria and 

methodology for the assessment of a new IMT radio interface. 

It is anticipated that the timeframe for Administration proposals will be focused in 2019. In 2019-

2020 the evaluation by independent external evaluation groups and definition of the new radio 

interfaces to be included in “IMT-2020” will take place. The process is planned to be completed 

in 2020 when a draft new ITU-R Recommendation with detailed specifications for the new radio 

interfaces will be submitted for approval within ITU-R. 

WRC-12 called for studies on future spectrum requirements and potential candidate frequency 

bands below 6 GHz for IMT and other terrestrial mobile broadband applications. Several bands 

under consideration at WRC-15 included spectrum vital to current and planned NASA operations: 

1400-1427 MHz; 2025-2110/2200-2290 MHz; and 5350-5470 MHz. 

WRC-15 made a number of spectrum allocations for mobile broadband/IMT. However, no 

allocation changes were made in the 1350-1400 MHz, 2025-2110 MHz, 2200-2290 MHz and 

5350-5470 MHz bands. In addition, NASA successfully obtained inclusion in the RR, mandatory 

out-of-band emission (OOBE) limits on IMT in the 1427-1452 MHz band to protect EESS 

(passive) in the adjacent 1400-1427 MHz band at levels sufficient to protect the passive operations. 

Given the seemingly endless efforts to find additional spectrum for IMT and related broadband 

services, NASA will have to continue to be vigilant in protecting spectrum in which it has equities. 

 

B5.2 Mobile-Satellite Service in 22-26 GHz 

One AI that raised concerns for NASA at WRC-12 involved the mobile satellite community 

seeking new allocations within the 4-16 GHz range. WRC-12 considered making additional 

allocations in several bands between 4 GHz and 16 GHz. Two of the six bands considered as 

possible candidate bands included the heavily utilized 7145-7235 MHz and 8400-8500 MHz space 

research service bands. Extensive study prior to WRC-12 had proved that sharing in these bands 

was not feasible, nor was it found to be feasible in any of the six candidate bands. NASA 

accomplished its goal to protect the 7/8 GHz space science bands, and WRC-12 decided to make 

no frequency allocation changes. However, the conference specified a WRC-15 AI that again 

caused NASA to strive to ensure protection of space science service allocations. 

WRC-15 considered spectrum requirements and possible additional spectrum allocations for the 

mobile-satellite service in the Earth-to-space and space-to-Earth directions, including a satellite 

component for broadband applications (e.g., IMT) within the frequency range from 22 GHz to 26 

GHz. WRC-12 called for sharing and compatibility studies towards additional allocations to the 

mobile-satellite service within portions of the allocated bands between 22 GHz and 26 GHz, while 
53 

ensuring protection of existing services within the bands.xv Some MSS interests identified the 

bands 23.15-25.55 GHz, 24.25-24.5 GHz and 25.25-25.5 GHz for possible re-allocation. 

For NASA, the main frequency bands at risk were: 

 The SRS Earth-to-space band 22.55-23.15 GHz 

 The Inter-satellite band 22.55-23.55 GHz and the Inter-satellite band 25.25-27.5 GHz 

 The EESS (passive) band 23.6-24 GHz as well as 22.21-22.5 GHz 

 The EESS/SRS space-to-Earth band 25.5-27.0 GHz 

As happened at WRC-12, WRC-15 decided not to provide any new MSS allocations within the 

22-26 GHz band, thus eliminating the risk from MSS to NASA’s equities within this frequency 

range. 

B5.3 MMSS at 7/8 GHz 

WRC-15 considered the possibility of allocating the bands 7375-7750 MHz and 8025-8400 MHz 

to the maritime-mobile satellite service, while ensuring compatibility with incumbent services. 

The potentially affected space science service bands were 8025-8400 MHz EESS (space-to-Earth) 

and 8400-8450 MHz SRS (space-to-Earth) (deep space). 

NASA was concerned about potential interference to EESS reception in 8025-8400 MHz at high 

latitudes from transmissions from ships operating in proximity to earth stations, as well as out-ofband interference to SRS (deep space) reception in the 8400-8450 MHz band. Large exclusion 

zones would be needed to avoid interference to existing and future EESS and SRS earth stations 

from a potentially large numbers of ships. Many of the more than 100 existing EESS and SRS 

earth stations are located near coastal areas (e.g., Svalbard, McMurdo, Maspalomas, Lannion, and 

Wallops) could be seriously affected by emissions from vessels navigating in the area up to 

distances of hundreds of kilometers from the coastline. The enforcement of large exclusion zones 

would not be feasible in practice, leading to interference that would be very difficult to track due 

to the mobile nature of the systems. Thus, NASA opposed an allocation to MMSS in 8025-8400 

MHz and strived to retain the current allocations. 

WRC-15 provided a MMSS downlink in the 7375-7750 MHz band and in alignment with NASA’s 

interests, did not allocate MMSS in the 8025-8400 MHz band. 

xv It also recognizes that unwanted emissions in the band 23.6-24 GHz will need to be limited to ensure protection of 

systems of the EESS (passive), SRS (passive) and radio astronomy services

                                                            
54 

Attachment C - NASA WRC-19 Objectives 

The WRC-19 agenda contains 16 individual AIs along with several standing AIs that are 

included in all WRC’s. Of these, NASA has primary interest in three items and concerns with 

eight items. Each of these AIs is summarized below and the potential impact to NASA is 

provided for those items of concern. 

C1 WRC-19 Items of Interest 

AI 1.2 - In-band power limits for MSS/Metsat/EESS earth stations in 401-403 MHz and 399.9-

400.05 MHz 

This item will examine the possible establishment of in-band power limits for earth stations 

operating in mobile-satellite service (MSS), the meteorological-satellite service (Metsat) and the 

Earth exploration-satellite service (EESS) in the frequency bands 401-403 MHz and 399.9-

400.05 MHz. 

AI 1.3 - Possible upgrade to primary for Metsat (space-to-Earth) allocation and a new primary 

EESS (space-to-Earth) allocation in 460-470 MHz 

This item is to consider the possibility of upgrading the secondary space-to-Earth Metsat 

allocation to primary status and adding a primary space-to-Earth EESS allocation in the 

frequency band 460-470 MHz. 

AI 1.7 - Requirements for SOS TT&C for Non-Geosynchronous Orbit (NGSO) short duration 

mission satellites 

This item calls for assessing the suitability of using existing Space Operations Service (SOS) 

allocations below 1 GHz to accommodate the telemetry, tracking and command (TT&C) 

requirements for non-geostationary satellites with short duration missions and if those allocations 

are determined to be unsuitable, consider possible new allocations or an upgrade of the existing 

allocations to the SOS within the frequency ranges 150.05-174 MHz and 400.15-420 MHz while 

protecting the incumbent services, both in-band as well as in adjacent bands. 

C2 WRC-19 Items of Concern 

AI 1.5 - Earth stations in motion communicating with FSS Geosynchronous Orbit (GSO) stations 

in 17.7-19.7 GHz (s-to-E) and 27.5-29.5 GHz (Earth-to-space) 

This item is to examine the possibility of using the frequency band 17.7-19.7 GHz in the spaceto-Earth direction and the frequency band 27.5-29.5 GHz in the Earth-to-space direction by earth 

stations in motion communicating with geostationary space stations in the FSS. NASA use of 

the 18.6-18.8 by the EESS (passive) could be impacted, as well as the potential for adjacent band 

interference into NASA’s Tracking and Data Relay Satellite System (TDRSS). 

AI 1.6 - NGSO FSS in (s-to-E): 37.5-39.5 GHz/39.5-42.5 GHz and (Earth-to-space): 47.2-

50.2 GHz/50.4-51.4 GHz 
55 

This item will study the technical, operational issues and regulatory provisions for the possibility 

of allowing non-geostationary FSS satellite systems to operate uplinks in the frequency bands 

37.5-39.5 GHz and 39.5-42.5 GHz and downlinks in the frequency bands 47.2-50.2 GHz and 

50.4-51.4 GHz. Bands that overlap NASA uses are identified in this item so there is a potential 

for impacts to NASA data communication and passive remote sensing equities. 

AI 1.13 – Identification of bands for the future development of IMT 

This item is essentially a continuation of the ongoing identification of spectrum for IMT and 

seeks the additional allocations to the mobile services on a primary basis in portion(s) of the 

frequency range between 24.25 and 86 GHz for the future development of IMT for 2020 and 

beyond. Specifically under examination are the frequency bands, which currently have primary 

MS allocations: 24.25-27.5 GHz, 37-40.5 GHz, 42.5-43.5 GHz, 45.5-47 GHz, 47.2-50.2 GHz, 

50.4-52.6 GHz, 66-76 GHz and 81-86 GHz. In addition, the frequency bands 31.8-33.4 GHz, 

40.5-42.5 GHz and 47-47.2 GHz may be considered for new allocations to the mobile service on 

a primary basis. 

This item encompasses many bands that overlap NASA uses so there is a great potential for 

adverse impacts to NASA data communication and passive remote sensing equities. 

AI 1.14 – Broadband delivered by high-altitude platform stations 

This item will examine facilitating access to broadband applications delivered by high-altitude 

platform stations in frequency band 38-39.5 GHz on a global level and in Region 2, in the 

frequency bands 21.4-22 GHz and 24.25-27.5 GHz. 

NASA equities adjacent to or using the 24.25-27.5 GHz band could be adversely impacted. 

AI 1.15 – Frequency identification for land-mobile and fixed services applications in the range 

275-450 GHz

This item calls for identification for use by administrations for the land-mobile and fixed service 

applications operating in the frequency range 275-450 GHz. 

The NASA passive remote sensing and radio astronomy operations in bands above 275 GHz 

need to be protected. 

AI 1.16 - Radio Local Area Network (RLANs) in bands between 5150-5925 MHz

This item is a continuation one segment of the WRC-15 IMT AI 1.1 and seeks to identify 

potential Wireless Access System (WAS)/RLAN mitigation techniques to facilitate sharing with 

incumbent systems in the frequency bands 5150-5350 MHz, 5350-5470 MHz, 5725-5850 MHz 

and 5850-5925 MHz. 

NASA passive remote sensing in the frequency band 5350-5470 MHz band could be severely 

impacted. 
56 

 

AI 9 Issue 1.4 - Stations on-board suborbital vehicles 

This item calls for studies of stations on board sub-orbital vehicles to identify any required 

technical and operational measures that could assist in avoiding harmful interference between 

radiocommunication services, as well as determining the stations’ spectrum requirements and, 

based on the outcome of those studies, consider a possible future AI for WRC-23. 

NASA uses many sub-orbital vehicles (e.g., sounding rockets) so has both interests and concerns 

with this item. 

AI 9 Issue 1.9 - Spectrum needs and possible FSS (Earth-to-space) allocation in 51.4-52.4 GHz 

band

This item calls for sharing and compatibility studies with existing services, on a primary and 

secondary basis, including in adjacent bands as appropriate, to determine the suitability, 

including protection of fixed and mobile services, of new primary Earth-to-space FSS allocations 

in the frequency band 51.4-52.4 GHz limited to FSS feeder links for geostationary orbit use, and 

the possible associated regulatory actions. 

NASA systems operating in the passive frequency band 52.6-54.25 GHz must be protected. 

Bands Under Consideration WRC-19 AIs

1.6 NGSO FSS 1.13 IMT 1.14 High Altitude 

Platform Station 9 Issue 1.9

 24.25-27.5 24.25-27.5 (Region 2) 

37.5-39.5 (space-to-Earth) 37-40.5 38-39.5 (globally) 

39.5-42.5 (space-to-Earth) 40.5-42.5 

47.2-50.2 (Earth-to-space) 47.2-50.2 

50.4-51.4 (Earth-to-space) 50.4-52.6 51.4-52.4 (Earth-to-space) 

Table C1: Frequency Overlaps of WRC-19 AIs 

 
57 

Attachment D - List of Acronyms 

Acronym Description 

4G Fourth Generation 

5G Fifth Generation 

AI Agenda Item 

ATK Alliant Technical Systems 

BR Radiocommunication Bureau 

CCP Commercial Crew Program 

CITEL Inter-American Telecommunication Commission 

COTS Commercial Orbital Transportation Services 

CPM Conference Prepatory Meeting 

CSMAC Commerce Spectrum Management Advisory Committee 

DoD Department of Defense 

DoS Department of State 

DSN Deep Space Network 

EESS Earth Exploration Satellite Service 

EHF Extremely High Frequency 

FAA Federal Aviation Administration 

FAS Frequency Assignment Subcommittee 

FCC Federal Communications Commission 

GAA General Access User 

GHz Gigahertz 

GOES Geostationary Operational Environmental Satellite 

GSO Geosynchronous Orbit 

HF High Frequency 

Hz Hertz 

IB International Bureau 

IMT International Mobile Telecommunication 

IR Infrared 

IRAC Interdepartment Radio Advisory Committee 

ISS International Space Station 

ITU International Telecommunication Union 

ITU-R ITU-Radiocommunications 

JTG Joint Task Group 

kHz Kilohertz 

LF Low Frequency 

LTE Long Term Evolution 

MF Medium Frequency 

MSS Mobile-Satellite Service 

MMSS Maritime Mobile-Satellite Service 

MOU Memorandum of Understanding 

NASA National Aeronautics and Space Administration 

NEN Near Earth Network 

NGSO Non-Geosynchronous Orbit 
58 

NOAA National Oceanic and Atmospheric Administration 

NOI Notice of Inquiry 

NPD NASA Policy Directive 

NPR NASA Process Requirements 

NPRM Notice of Proposed Rulemaking 

NTIA National Telecommunications and Information Administration 

OCO-2 Orbiting Carbon Observatory-2 

OET Office of Engineering and Technology 

OSM Office of Spectrum Management 

PCAST President’s Council of Advisors on Science and Technology 

PNT EXCOM Space-based Positioning, Navigation and Timing Executive Committee 

PPSG Policy and Plans Steering Group 

RAS Radio Astronomy Service 

RCS Radio Conference Subcommittee 

RF Radiofrequency 

RFA RF Authorizations 

RLAN Radio Local Area Network 

RR Radio Regulations 

RRB Radio Regulations Board 

SAR Synthetic Aperture Radar 

SAS Spectrum Access System 

SCaN Space Communications and Navigation 

SDO Solar Dynamics Observatory 

SFCG Space Frequency Coordination Group 

SGs Radiocommunication Study Group 

SHF Super High Frequency 

SLS Space Launch System 

SMAP Soil Moisture Active Passive 

SN Space Network 

SpaceX Space Exploration Technologies 

SRS Space Research Service 

SSD Spectrum Services Division 

STA Special Temporary Authorization 

STS Space Transportation System 

SWAVES Stereo/Waves 

TDRS Tracking and Data Relay Satellite 

TT&C Tracking, Telemetry, and Commanding 

UAVs Unmanned Aeronautical Vehicles 

UHF Ultra High Frequency 

U-NII Unlicensed National Information Infrastructure 

UV Ultraviolet 

VLF Very Low Frequency 

WARC World Radio Administrative Conference 

WRC World Radiocommunication Conferences 

WTB Wireless Telecommunications Bureau 
59 

Attachment E - List of Figures 

Figure Page 

Figure 1.1: Representative NASA Spectrum Use 2 

Figure 1.2: Cisco Forecasts Mobile Data Traffic (2014-2019) 3 

Figure 2.1: Depiction of the Electromagnetic Spectrum 7 

 

Figure 2.2: Letter Designation of RF Bands 7 

Figure 2.3: ITU Band Designation 8 

Figure 2.4: Table of Frequency Allocations 9 

Figure 3.1: US Spectrum Management Process 14 

Figure 3.2: ITU Structure 20 

Figure 4.1: NASA Spectrum Management Organization 24 

Figure 4.2: Frequency Authorization Process 27

Figure 5.1: Representative NASA Spectrum Use 29

Figure 6.1: The GPS Constellation flies in medium Earth orbit at an altitude of 

 20,200 km (12,550 miles) 44 

 
60 

Attachment F - Tables 

Table Page 

Table 2.1: Spectrum Bands Used by NASA 8 

Table B1: NASA WRC-15 Spectrum Objectives 49 

Table B2: NASA WRC-15 Spectrum Concerns 51 

Table C1: Frequency Overlaps of WRC-19 AIs 56