SPECTRUM 

MANAGEMENT

Incentives, 

Opportunities, and 

Testing Needed to 

Enhance Spectrum 

Sharing

Report to Congressional Committees

November 2012

GAO-13-7

United States Government Accountability Office

GAO
United States Government Accountability Office

Highlights of GAO-13-7, a report to 

congressional committees. 

November 2012 

SPECTRUM MANAGEMENT

Incentives, Opportunities, and Testing Needed to 

Enhance Spectrum Sharing 

Why GAO Did This Study

The increasing popularity of wireless 

devices that use spectrum, combined

with federal spectrum needs for 

national defense and other public 

safety activities, have created 

concerns that a “spectrum crunch” is 

looming. However, there is also 

evidence that at any given time or 

place, spectrum lies fallow or is only 

intermittently used. In an effort to use 

spectrum as efficiently as possible, 

advisory groups and others have 

proposed solutions to share spectrum. 

This requested report examines (1) 

what factors prevent users from 

sharing spectrum more frequently and

(2) what actions the Federal 

Communications Commission (FCC), 

the National Communications 

Information Administration (NTIA), and 

others can take to encourage more 

sharing and efficient spectrum use. 

GAO reviewed plans and documents 

from FCC and NTIA regarding their 

management of nonfederal and federal 

spectrum-sharing activities, 

respectively. GAO also interviewed 

federal and commercial spectrum 

users, industry and academic experts,

and other stakeholders. 

What GAO Recommends

FCC and NTIA should jointly (1) report 

to Congress on the potential merits 

and effects of a spectrum fee, (2)

determine how to best promote

spectrum research and development, 

and (3) evaluate what regulatory 

changes might improve the spectrum 

sharing process. The agencies 

generally agreed with GAO’s findings 

but identified ongoing efforts that 

address the recommendations. GAO 

has modified the recommendations as 

described further in the report. 

What GAO Found

Some spectrum users may lack incentive to share spectrum or otherwise use it 

efficiently, and federal agencies and private users currently cannot easily identify 

spectrum available for sharing. Typically, paying the market price for a good or 

service helps to inform users of the value of the good and provides an incentive 

for efficient use. Federal agencies, however, pay only a small fee to the NTIA for 

spectrum assignments and therefore have little incentive to share spectrum. 

Federal agencies also face concerns that sharing could risk the success of 

security or safety missions, or could be costly in terms of upgrades to more 

spectrally efficient equipment. Nonfederal users, such as private companies, are 

also reluctant to share spectrum. For instance, license holders may be reluctant

to encourage additional competition, and companies may be hesitant to enter 

into sharing agreements that require potentially lengthy and unpredictable 

regulatory processes. Sharing can be costly for them, too. For example, 

nonfederal users may be required to cover all interference mitigation costs to use 

a federal spectrum band, which might include multiple federal users. Sharing can 

also be hindered because information on federal spectrum use is lacking and 

information regarding some federal spectrum use may never be publicly 

available, a situation that makes it difficult for users to identify potential spectrum 

for sharing. 

Federal advisors, agency officials, and experts have identified several options 

that could provide greater incentives and opportunities for more efficient 

spectrum use and sharing by federal and nonfederal users. These options 

include, among other things: considering spectrum usage fees to provide 

economic incentive for more efficient use and sharing; identifying more spectrum 

that could be made available for unlicensed use, since unlicensed use is 

inherently shared; encouraging research and development of technologies that 

can better enable sharing; and improving and expediting regulatory processes 

related to sharing. However, these options involve implementation challenges. 

For example, setting spectrum usage fees for federal users may not result in 

creating the proper incentives, because agency budgets might simply be 

increased to accommodate their current use. While new technologies that 

overcome some of the inherent challenges with sharing spectrum are being 

developed, proving those technologies under real-world conditions can be 

difficult, and few incentives exist at the federal level to encourage such 

technology development. Finally, FCC and NTIA have taken some actions to 

potentially reduce the amount of time and even the need for potential 

rulemakings sometimes associated with spectrum sharing, but stakeholders and 

experts suggested that more could be done to expedite the approval process, 

such as automating some steps and developing better capabilities to track the 

status of spectrum-sharing applications. However, any changes to federal 

regulatory processes related to spectrum management and sharing would need 

to be carefully studied with respect to potential benefits and costs.

View GAO-13-7. For more information, contact 

Mark Goldstein at (202) 512-2834 or 

goldsteinm@gao.gov. 
Page i GAO-13-7 Spectrum Sharing

Letter 1 

Scope and Methodology 3

Background 4

Some Users Lack Incentives and Face Barriers to Sharing 

Spectrum 11

Incentives and Opportunities to Share Spectrum Could Be 

Expanded 17

Conclusions 28

Recommendations for Executive Action 28

Agency Comments and Our Evaluation 29

Appendix I Federal Agencies, Nonfederal Spectrum Users and Experts 

Interviewed Regarding Spectrum Sharing 32

Appendix II Comments From the Department of Commerce 34

Appendix III Comments From the Federal Communications Commission 37

Appendix IV GAO Contact and Staff Acknowledgements 39

Table

Table 1: Subject Matter Experts Interviewed 33

Figures

Figure 1: Percentage of Federal Agency Frequency Assignments, 

2012 6

Figure 2: Illustration and Examples of Spectrum Sharing 7

Contents 
Page ii GAO-13-7 Spectrum Sharing

Abbreviations

4G fourth generation

AIP Administered Incentive Pricing

CSMAC Commerce Spectrum Management Advisory Committee

DARPA Defense Advanced Research Projects Agency

FCC Federal Communications Commission

FSMS Federal Spectrum Management System

GHz gigahertz

IRAC Interdepartment Radio Advisory Committee

LTE Long Term Evolution

MHz megahertz 

NTIA National Telecommunications and Information

 Administration

OMB Office of Management and Budget

PCAST President’s Council of Advisors on Science and

 Technology 

Wi-Fi wireless fidelity

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Page 1 GAO-13-7 Spectrum Sharing

United States Government Accountability Office 

Washington, DC 20548

November 14, 2012

The Honorable Fred Upton

Chairman

The Honorable Henry A. Waxman

Ranking Member

Committee on Energy and Commerce

House of Representatives

The Honorable John D. Rockefeller IV

Chairman

The Honorable Kay Bailey Hutchison

Ranking Member

Committee on Commerce, Science, and Transportation

United States Senate

The Honorable Greg Walden

Chairman

The Honorable Anna G. Eshoo

Ranking Member

Subcommittee on Communications and Technology

Committee on Energy and Commerce

House of Representatives

The propagation and popularity of smart phones, tablets, and other 

wireless devices has created an explosion in the demand for and use of 

more radio frequency spectrum to support services and data 

transmissions on these devices, particularly in dense, urban areas. 

Federal users—mostly government agencies—also require spectrum for 

national defense, homeland security, and other vital mission activities. To 

date, however, nearly all usable radio spectrum has been allocated either 

by the National Telecommunications and Information Administration 

(NTIA) within the Department of Commerce for federal government use or 

by the Federal Communications Commission (FCC) for commercial and 

other nonfederal use. Therefore, virtually no “green fields” of spectrum 

are currently available to allocate to new uses or technologies. Going 

forward, this scarcity could have implications for our economy, our 

competitiveness in global markets, and the ability of government at all 

levels to meet its key missions.

This situation notwithstanding, there is substantial evidence that at any 

given point in time at any given place, there is fallow or intermittently used 

 
 

Page 2 GAO-13-7 Spectrum Sharing

spectrum—certainly in sparsely populated rural areas, and even in 

heavily trafficked urban areas.1 Some experts suggest that the scarcity of 

spectrum in the United States is to some extent a result of the manner in 

which this resource has been allocated, managed, and used, rather than 

because of a physical scarcity of the resource. In an effort to address 

increasing demands for spectrum access, the current and past 

Administrations, Congress, FCC, and others have proposed a variety of 

policy, economic, and technological solutions to address the availability 

and efficient use of spectrum. For example, in 2010, the administration 

set a goal for 500 megahertz (MHz) of federal and nonfederal spectrum 

currently being unused or under-used to be repurposed for mobile 

broadband use. However, we have previously reported that repurposing 

spectrum has been and can be a contentious and highly protracted 

process, typically taking years.2 As a result, solutions geared toward 

greater sharing of spectrum among users—federal and nonfederal—have 

become more attractive because of the potential access to more 

spectrum and opportunities to use spectrum more efficiently that sharing 

presents. For instance, the President’s Council of Advisors on Science 

and Technology (PCAST) recently recommended that 1,000 MHz of 

spectrum previously occupied only by federal users be shared with 

nonfederal users.3

In light of these issues, and in response to your request, we examined (1) 

what factors currently prevent users from sharing spectrum more 

frequently and (2) what actions FCC, NTIA and others can take to 

encourage more sharing and more efficient spectrum use.

 

1

See Commerce Spectrum Management Advisory Committee, Incentives Subcommittee

Final Report (Washington, D.C.: January 11, 2011); President’s Council of Advisors on 

Science and Technology, Report to the President; Realizing the Full Potential of 

Government-held Spectrum to Spur Economic Growth, (Washington, D.C.: July 2012); 

and Department of Commerce, Spectrum Management for the 21st Century, (Washington, 

D.C.: 2008).

2

GAO, Commercial Spectrum: Plans and Actions to Meet Future Needs, Including 

Continued Use of Auctions, GAO-12-118 (Washington, D.C.: November 2011).

3

Report to the President: Realizing the Full Potential of Government-held Spectrum to 

Spur Economic Growth. 
 

Page 3 GAO-13-7 Spectrum Sharing

We reviewed federal legislation, regulations, and processes regarding 

spectrum management and spectrum sharing, including NTIA’s Manual of 

Regulations and Procedures for the Federal Radio Frequency 

Management; as well as various FCC plans, notices, orders and other 

publications related to spectrum management and sharing. We conducted 

multiple interviews with FCC, NTIA, and various advisory committees, 

such as the Commerce Spectrum Management Advisory Committee 

(CSMAC). We selected 7 of the 19 Interdepartment Radio Advisory 

Committee4

We also interviewed a variety of stakeholders and experts outside the 

federal government with knowledge and experience related to spectrum 

sharing issues. These stakeholders and experts fell into four groups:

(IRAC) agencies—the Departments of Commerce, Defense, 

Homeland Security, Interior, Justice, Transportation, and Treasury—

based on which agencies were most likely to have experience with 

spectrum sharing. We interviewed the spectrum managers for these 

departments to better understand their experiences with sharing, 

including successes and challenges, and analyzed the extent to which 

spectrum sharing was a part of their spectrum management plans.

• Nonfederal spectrum users: We interviewed officials from seven

commercial entities such as Verizon, Sprint, and other wireless and 

communications companies. We also interviewed local government 

officials regarding their spectrum sharing experiences. We selected 

these nonfederal users based on their experiences with sharing 

spectrum, or based on their vested interest in spectrum policy.

• Companies that create spectrum-sharing solutions: We interviewed 

two companies that create spectrum sharing technologies. We 

selected these companies based on recommendations from spectrum 

experts and federal agency officials about which companies were 

most active with spectrum sharing technology development.

• Industry and academic experts: We interviewed 16 industry and 

academic experts. We selected these experts based on their 

published and recognized research credentials for their work on 

 

4

IRAC’s main function is to assist NTIA in assigning frequencies and in developing 

policies, procedures, and technical criteria on management and use of spectrum. The 

Department of Defense has multiple participants on the IRAC from the Army, Navy and Air 

Force. The other member agencies include the Departments of Agriculture, Energy, State 

and Veterans Affairs; Broadcasting Board of Governors; United States Coast Guard; 

National Aeronautics and Space Administration; National Science Foundation and United 

States Postal Service.

Scope and 

Methodology
 

Page 4 GAO-13-7 Spectrum Sharing

spectrum management, spectrum sharing and the economic impacts 

of spectrum related policies, and on other stakeholders’ and experts’ 

recommendations.

• International spectrum management officials: We interviewed 

spectrum management officials from Canada, the United Kingdom, 

and Australia to compare other countries’ spectrum management and 

spectrum-sharing practices to that of the United States. We chose 

these three countries based on their level of experience dealing with 

spectrum-sharing issues. We also interviewed officials from the 

International Telecommunication Union to understand its role in 

advising international spectrum management and spectrum sharing 

policies.5

We also completed a literature search and reviewed recent reports and 

articles related to spectrum sharing, including academic and government 

reports as well as speeches and articles by the groups of officials and 

experts we interviewed as described above.

A complete list of the departments and agencies, experts and companies 

that we interviewed can be found in appendix I. The information and 

perspectives that we obtained from the interviews may not be generalized 

to all experts and industry stakeholders that have an interest in spectrum 

policy. Rather, comments and views were reviewed in context with 

current literature on spectrum management issues.

We conducted this performance audit from September 2011 to October 

2012 in accordance with generally accepted government auditing 

standards. Those standards require that we plan and perform the audit to 

obtain sufficient, appropriate evidence to provide a reasonable basis for 

our findings and conclusions based on our audit objectives. We believe 

that the evidence obtained provides a reasonable basis for our findings 

and conclusions based on our audit objectives.

In the United States, responsibility for managing spectrum—including 

allocating, assigning, regulating, and facilitating the sharing of spectrum—

 

5

The International Telecommunication Union allocates global radio spectrum and 

develops technical standards for information and communication technologies and their 

networks, among other things. It was founded in 1865 and became a specialized agency 

of the United Nations in 1947. Its membership comprises 193 countries and over 700 

private-sector entities. 

Background
 

Page 5 GAO-13-7 Spectrum Sharing

is divided between two agencies, NTIA and FCC. NTIA and FCC jointly 

determine the amount of spectrum allocated for federal and nonfederal 

use, including both exclusive and shared use. After this allocation occurs, 

in order to use spectrum, nonfederal users, such as wireless companies 

and local governments, must follow rules and be authorized by FCC to 

use specific frequencies.6 When spectrum is repurposed, FCC may also 

be authorized to hold an auction to distribute licenses through a bidding 

process. Federal users, like the military, must follow rules, and obtain 

frequency assignments from NTIA.7

Federal agencies use spectrum to help meet a variety of missions, 

including emergency communications, national defense, land 

management, and law enforcement. More than 60 federal agencies and 

departments combined have over 240,000 frequency assignments. As of 

September 2012, 9 departments and agencies had the vast majority of 

the assignments: the Department of Defense, the Federal Aviation 

Administration, the Department of Justice, the Department of Homeland 

Security, the Department of the Interior, the Department of Agriculture, 

the United States Coast Guard, the Department of Energy, and the 

Department of Commerce, respectively, hold 94 percent of all federally 

assigned spectrum. (See fig. 1.) Nonfederal entities (which include 

commercial companies and state and local governments) also use 

spectrum to provide a variety of services. For example, state and local 

police departments, fire departments, and other emergency services 

agencies use spectrum to transmit and receive critical voice and data 

communications, while commercial entities use spectrum to provide 

wireless services, including mobile voice and data, paging, broadcast 

radio and television, and satellite services.

Both NTIA and FCC have authority to 

issue rules and regulations on use of spectrum as necessary to ensure 

effective, efficient, and equitable domestic spectrum use.

 

6

Act of June 19, 1934, ch. 652, 48 Stat. 1064, as amended by the Middle Class Tax Relief 

and Job Creation Act of 2012, Pub. L. No. 112-96, Title VI, §§ 6401, 6402, 126 Stat. 156, 

223-225 (Feb. 22, 2012) (Communications Act), codified as title 47, United States Code 

Annotated §§ 307-3011 (Westlaw 2012). 

7

Telecommunications Authorization Act of 1992, Pub. L. No. 102-538, Title I, 106 Stat. 

3533 (Oct. 27, 1992), as amended, codified at 47 U.S.C. ch. 8 (NTIA Authorization Act). 
 

Page 6 GAO-13-7 Spectrum Sharing

Figure 1: Percentage of Federal Agency Frequency Assignments, 2012

Not all spectrum has equal value. The spectrum most highly valued 

generally consists of frequencies between 225 and 3700 MHz, as these 

frequencies have properties well suited to many important wireless 

technologies, such as mobile devices, and radio and television 

broadcasting. According to NTIA’s Office of Spectrum Management, 

federal agencies have exclusive use of about 18 percent of this highly 

valued spectrum, while nonfederal users have exclusive licenses to 

approximately 33 percent.8

 

8

For many mobile radio systems, this is the portion of the spectrum where scarcity 

concerns are the greatest. However, for some industry representatives, the range of highvalue spectrum is larger, located anywhere between 100 MHz to 6 GHz. As spectrumdependent technologies improve over time, the definition of high-value spectrum can 

change. 

The remainder of this spectrum is allocated to 

shared use. The types of and degree of sharing between governmental 

and nongovernmental users varies across the bands included within this 

shared spectrum. In addition, increasing demands on spectrum mean that 

federal and nonfederal users increasingly occupy adjacent bands, which 

in practice necessitates intensive coordination on technical rules. 

Estimates of the extent of predominant federal use within the spectrum 

allocated for shared use vary depending on the particular evaluation 

model and analyses employed. Depending on the estimate used, the total 
 

Page 7 GAO-13-7 Spectrum Sharing

percentage of the most highly valued spectrum exclusively or 

predominantly used by the federal government ranges from 

approximately 39 percent to 57 percent.

Spectrum sharing can be defined as the cooperative use of common 

spectrum that allows disparate missions to be achieved. In this way, 

multiple users agree to access the same spectrum at different times or 

locations, as well as negotiate other technical parameters, to avoid 

adversely interfering with one another. For sharing to occur, users and 

regulators must negotiate and resolve where (geographic sharing), when 

(sharing in time), and how (technical parameters) spectrum will be used. 

(See fig. 2.)

Figure 2: Illustration and Examples of Spectrum Sharing

Both FCC and NTIA manage the process that leads to spectrum sharing 

between federal and nonfederal users. The steps involved in the process 

include the following:
 

Page 8 GAO-13-7 Spectrum Sharing

• Prior to authorizing a nonfederal user to share spectrum with federal 

users, FCC will coordinate with NTIA on the allocation and service 

rulemakings required that define the technical and operating 

conditions for shared access to spectrum.9

• To have access to federal spectrum, the nonfederal entity must also 

obtain an FCC license. FCC will coordinate the allocation change or 

license application, including technical and operational conditions, for 

sharing federal spectrum through the Frequency Assignment 

Subcommittee of IRAC.

NTIA will provide draft 

findings to IRAC, which provides advice to NTIA regarding federal 

spectrum. FCC participates in IRAC as a liaison. IRAC determines 

which agencies would be affected by the nonfederal use of spectrum 

and acts as the forum where those agencies consider how they may 

accommodate the nonfederal user. According to NTIA, any nonfederal 

user may approach NTIA and IRAC to discuss a proposal to use 

federal or shared bands to determine any obstacles and best ways 

forward. In some cases, FCC encourages nonfederal applicants to 

work directly with concerned agencies to try to reach agreement on an 

arrangement that could then be adapted to FCC rules or licenses. 

Similarly, if federal users request frequency assignments in 

nonfederal or shared bands, these requests must be coordinated with 

FCC through IRAC. According to NTIA, thus far, all requests by 

federal entities to change an allocation have gone through NTIA to 

FCC and have required an FCC rulemaking.

• Next, before any spectrum sharing takes place in federal or shared 

spectrum, NTIA must vet the coordinating parties’ requests, assign 

frequencies, and ensure that the systems the parties will be using—

such as the land mobile radios used by state and local emergency 

responders that share spectrum with federal users—are compatible.

When spectrum sharing occurs solely among federal users within federal 

exclusive bands, IRAC’s Frequency Assignment Subcommittee, using 

NTIA’s database of federal frequency assignments, reviews the spectrum 

 

9

Under a Memorandum of Understanding between FCC and NTIA, all proposed actions 

that could potentially cause interference to government operations are coordinated with 

NTIA. In cases where a rulemaking is necessary to provide parties with access to federal 

spectrum, the rulemaking is coordinated with NTIA. For instance, FCC followed this 

process when a medical devices company sought to share spectrum used by the 

Department of Defense and other federal agencies. The proposed devices required wider 

bandwidths of spectrum to operate than similar medical devices that previously operated 

in medical network spectrum bands. To accommodate this and other similar uses, an FCC 

rulemaking was required to expand the amount of spectrum set aside for medical implant 

devices. 
 

Page 9 GAO-13-7 Spectrum Sharing

requests and identifies any potential interference concerns prior to

commencing the shared use. Federal sharing occurs routinely. For 

example, the Departments of Defense, and Transportation, and 

Department of Commerce’s National Oceanic and Atmospheric 

Administration share spectrum for directing aircraft and monitoring 

weather conditions. The Department of Defense also frequently shares 

spectrum among its own various programs, internal services and 

agencies.

When sharing occurs solely among nonfederal users, FCC seeks to allow 

flexibility for license holders to coordinate and negotiate spectrum-sharing 

agreements among themselves. FCC provides flexibility in a couple of 

ways. One way is through the expanded issuance of flexible use licenses. 

As opposed to traditional licenses, where usage is limited to the specific 

terms of the license (e.g., TV broadcast stations in specific markets), 

flexible use licenses allow for a wider array of uses without having to seek 

additional FCC authorization. Licensing expands the pool of potential 

entities that would be able to innovate and share the spectrum beyond 

those that would use the spectrum in a similar manner. However, with 

both traditional and flexible use licenses, if a proposed shared use is not 

consistent with the terms of a license, an FCC rulemaking would be 

required to allow that use. Another way FCC provides flexibility is with 

respect to its secondary market policies and rules that permit licensees to 

share their spectrum resource through spectrum lease arrangements.10

Spectrum sharing also occurs through unlicensed access by anyone 

using wireless equipment certified by FCC for those frequencies. 

Equipment such as wireless microphones, baby monitors, and garage 

door openers share spectrum with other services on a non-interference 

basis typically within a limited geographic range and at low power levels 

to avoid interference with higher priority uses. In contrast with most 

licensed spectrum use, unlicensed users have no regulatory protection 

While FCC tracks these secondary market transactions, users negotiate 

their own terms, making it difficult to gauge the extent to which sharing 

occurs among these users, if at all.

 

10In the Matter of Promoting Efficient Use of Spectrum through Elimination of Barriers to 

the Development of Secondary Markets, 18 FCC Rcd. 20604 (2003) (First Report and 

Order); 18 FCC Rcd. 24817 (2003) (Erratum); 19 FCC Rcd. 17503 (2004) (Second Report 

and Order), , 22 FCC Rcd. 7209 (April 11, 2007) (Third Report and Order); see also 47 

C.F.R. Pt. 1, Subpt. X.
 

Page 10 GAO-13-7 Spectrum Sharing

against interference from other licensed or unlicensed users in the band. 

Unlicensed use is regulated to ensure that devices do not cause 

interference to other operations in the spectrum. For example, wireless 

fidelity (Wi-Fi)11

Many technological developments have also increased spectrum 

efficiency and further enabled sharing. For example, dynamic spectrum 

access technologies under development could allow equipment to sense 

and select among available frequencies in an area, efficiently using 

whatever frequencies might be available. This allows users to share 

frequencies in the same location in very small increments of time.

devices share some band segments in the 5 gigahertz 

(GHz) range with military radar subject to the condition that the Wi-Fi 

devices are capable of spectrum sensing via dynamic frequency 

selection; if the Wi-Fi device detects a radar signal, the device must 

immediately vacate the channel the radar signal is on.

12

Software-defined radios also use spectrum more efficiently by accessing 

different frequencies in one location. In addition, these radios use more 

efficient batteries that allow them to perform more sophisticated tasks 

while using less spectrum than traditional radios. As another example, 

small cell technology allows users to share the same frequencies in close 

proximity to each other. Further, emerging fourth generation (4G) Long 

Term Evolution (LTE) technologies, as used by some smart phones to 

access the Internet, promise improvement in data transfer speeds.13

Research continues on these and other fronts to enable more efficient 

use of spectrum, including sharing.

 

11Wi-Fi is a technology that is often used in conjunction with a customer’s Internet service 

to connect devices, such as computers and smart phones, located within the customer’s 

home or business to the Internet.

12Dynamic spectrum access technologies are currently able to sense for available 

frequencies before transmission (listen before talk), but not sense during transmission. 

(listen while talk) Sensing before transmission involves sensing available frequencies, 

then jumping and transmitting, which causes lag time. The technology to enable sensing 

during transmission, which would allow a user to seamlessly continue communication 

while moving geographically through spectrum bands is still under development. 

13The international definition of 4G technology is transmitting data at 100 Megabits per 

second, but current 4G LTE technologies deliver top speeds of only 15 Megabits per 

second.
 

Page 11 GAO-13-7 Spectrum Sharing

While federal spectrum users often share spectrum among themselves, 

they may have little economic incentive to otherwise use spectrum 

efficiently, including sharing it with nonfederal users. From an economic 

perspective, when a consumer pays the market price for a good or 

service and thus cannot get more of it without this expense, the consumer 

has an incentive to get the most value and efficiency out of the good as 

possible. If no price is attached to a good—which is essentially the case 

with federal agencies’ use of spectrum14—the normal market incentive to 

use the good efficiently may be muted. In the case of federal spectrum 

users, obtaining new spectrum assignments may be difficult, so an 

agency may have an incentive to conserve and use the spectrum it 

currently has assigned to it or currently shares efficiently, but the extent of 

that incentive is likely weaker than if the agency had to pay market price 

for all of its spectrum needs. Consequently, federal spectrum users do not 

fully face a market incentive to conserve on their use of spectrum or use it 

in an efficient manner. The full market value of the spectrum assigned to 

federal agencies has not been assessed, but, according to one industry 

observer, would most likely be valued in the tens of billions of dollars. 

Similarly, many nonfederal users, such as television broadcasters and 

public safety entities, did not pay for spectrum when it was assigned to 

them and do not pay the full market price for their continuing use of 

spectrum, so, like federal agencies, they may not fully have market-based 

incentives to use spectrum efficiently.15

In contrast, licensed, commercial users that purchase spectrum at auction 

generally have market incentives to use their spectrum holdings 

efficiently, but these users also have incentives that work against their 

 

14Agencies pay only a small, annual fee for their spectrum which is not comparable to its 

full market value. According to NTIA, federal agencies pay $122 for each frequency 

assignment, totaling about $30 million paid by 47 agencies to NTIA for fiscal year 2012.

15It is the case, however, that when ownership of these companies changes hands, 

purchasers do pay for the value of all the assets of the company—including the value of 

the spectrum license.

Some Users Lack 

Incentives and Face 

Barriers to Sharing 

Spectrum

Some Users Lack 

Economic Incentives to 

Share Spectrum
 

Page 12 GAO-13-7 Spectrum Sharing

sharing spectrum. FCC officials and industry stakeholders and experts 

told us that these users may prefer not to share their unused spectrum 

because they are concerned about the potential for interference to 

degrade service quality to their customers. Also, they may not want to 

give potential competitors access to spectrum. Industry stakeholders and 

experts also said that companies seeking spectrum may prefer obtaining 

exclusive spectrum licenses over sharing spectrum that is licensed to 

another company or federal user, given uncertainties about regulatory 

approvals, interference, and enforcement if interference occurs.

Federal agencies will not risk mission failure, particularly when there are 

security and public safety implications. According to the agency officials 

we contacted, federal agencies will typically not agree to share spectrum 

if it puts achievement of their mission at risk. The officials stressed that 

when missions have security and safety implications, sharing spectrum 

may pose unacceptable risks. For example, the military tests aircraft and 

trains pilots using test ranges that can stretch hundreds of miles, 

maintaining constant wireless contact. While there may be times and 

locations where the frequencies are not in use because aircraft are not in 

the area, communication frequencies in the test ranges cannot be shared, 

according to officials in the Department of Defense, because even 

accidental interference in communications with an aircraft could result in 

catastrophic mission failure. Further, sharing information about such 

flights could expose pilots and aircraft, or the military’s larger mission, to 

increased risk. Federal law enforcement agencies are also concerned 

about how sharing spectrum could put missions at risk. For example, 

officials at the Departments of Treasury and Justice explained that 

interference with communications among agents could put the agents in 

danger and cause them to miss mission critical information. According to 

officials from the Department of Justice, the department tested sharing 

spectrum with a major commercial carrier in a metropolitan area in 2008 

and concluded that the department and the carrier t could not co-exist on 

the same spectrum. NTIA also reported that although sharing should be 

accommodated when appropriate, it is necessary to establish clear 

regulatory mechanisms for sharing to ensure that federal users are not 

required to assume responsibility for mitigating interference.16

 

16United States Department of Commerce, Relocation of Federal Radio Systems from the 

1710- 1755 MHz Spectrum Band: Fourth Annual Progress Report (March 2011).

Several Barriers Can Deter 

Users from Sharing 

Spectrum
 

Page 13 GAO-13-7 Spectrum Sharing

According to FCC officials, concerns about risk of mission failure can 

drive conservative technical standards for federal agencies’ missions that 

can make sharing spectrum impractical. In general, the technical 

analyses and resulting standards federal agencies develop are based on 

worst-case scenarios and not on assessments of the most likely scenario 

or a range of scenarios. Moreover, in contrast to FCC’s open rulemaking 

process, there is little opportunity for public input to the federal agencies’ 

standards-setting process. Stakeholders may meet or have discussions 

with NTIA and the relevant federal agencies, but this occurs without any 

formal public process. Nor do stakeholders have any effective means to 

appeal other than by asking FCC to reject NTIA’s analysis or standards.

Spectrum sharing can be costly. FCC and NTIA officials, as well as other 

agency officials and an industry stakeholder, told us that sharing federal 

spectrum can be costly for both the nonfederal and federal users seeking 

to share for the following reasons:

• Users may find that mitigation of potential interference can be costly in 

terms of equipment design and operation. For example, according to 

officials from one agency, sharing spectrum outside a law 

enforcement environment would require cognitive radios, which could 

be costly.17

• Users applying to share federal frequencies may find that those 

frequencies are being used by more than one federal agency or 

program. As a result of needing to mitigate interference for multiple 

users, costs to share spectrum in that band could increase.

• Federal users often use and rely on proven older technology that was 

designed to use spectrum to meet a specific mission and may be less 

efficient than more modern systems. Limited budgets may also 

prevent users from being able to invest in newer technology that can 

facilitate easier sharing. For example, officials at one agency said they 

maintain and use systems until the end of the system’s life cycle to 

assure continuity of operations and security.

Spectrum-sharing approval and enforcement processes can be lengthy 

and unpredictable. FCC and NTIA processes can cause two main 

problems when nonfederal users seek to share federal spectrum, 

according to stakeholders:

 

17 In any moment in time, cognitive radios have the ability to determine and use spectrum 

that is unused and available.
 

Page 14 GAO-13-7 Spectrum Sharing

• The spectrum-sharing approval process between FCC and NTIA can 

be lengthy and unpredictable, and the risk associated with it can be 

costly for new entrants. FCC officials told us that its internal processes 

can potentially last years if a rulemaking is required to allow shared 

use of spectrum.18 In addition to that time, NTIA officials said that 

IRAC’s investigation of potential harmful interference could also take 

months. In one example, federal users currently share the spectrum 

band of 413-457 MHz with a nonprofit medical devices provider. The 

spectrum is used for transmissions related to implant products for 

veterans. It took FCC, NTIA and the spectrum users approximately 2 

years (from 2009 to 2011) to facilitate this arrangement because an 

FCC rulemaking was required and all parties agreed to a lengthy 

evaluation of potential interference.19

• Stakeholders we interviewed told us that when federal and nonfederal 

users share spectrum, both parties worry that harmful interference 

may affect their missions or operations if the other party overreaches 

or does not follow the agreement. They also fear that any 

enforcement actions taken by FCC will happen too slowly to protect 

their interests and that enforcement outcomes may be unfavorable. 

According to officials at one agency, there are not many examples of 

large scale sharing of federal and nonfederal systems and limited 

The nonprofit in this case was 

funded by an endowment and was not dependent on income from the 

device to sustain itself during this process, but such delays, and the 

potential for a denial because of findings of harmful interference risks, 

could discourage for-profit companies from developing and investing 

in business plans that rely on sharing federal spectrum. However, 

officials at one agency commented that they have seen the timing of 

NTIA approval of federal participation drastically reduced over the 

past several years, from many months to less than a month as a 

result of additional coordination and negotiation of sharing done prior 

to the submission of frequency requests.

 

18The time it takes to complete rules varies because of the unique nature of each 

rulemaking. Certain factors, such as the technical complexity of the issue being addressed 

and the priority of the rulemaking in comparison to other issues, can also affect 

rulemaking time frames. FCC’s rulemaking process includes multiple steps as outlined by 

law with opportunities for the public to participate. FCC is generally not required to 

complete rules within limited time frames.

19According to Department of Defense officials, both the federal stakeholders, including 

the Department of Defense, and the medical device provider were involved in the 

interference analysis.
 

Page 15 GAO-13-7 Spectrum Sharing

governance and enforcement mechanisms exist to support such 

efforts.

Similar problems can arise when nonfederal users share spectrum with 

each other. Distrust of each other and of FCC’s decision-making and 

enforcement processes could discourage sharing. For example, if a 

proposed shared use does not fall within the terms of the incumbent’s 

license, FCC may need to engage in rulemaking proceedings, which can 

be long and unpredictable and can make spectrum-sharing arrangements 

unattractive to companies that otherwise might consider sharing.

Besides lacking incentives and overcoming other barriers, users may also 

have difficulty identifying spectrum available for sharing because data on 

available spectrum is incomplete or inaccurate, and information on some 

federal spectrum usage is not publicly available. According to NTIA 

officials, coordinating spectrum sharing requires accurate data on users, 

frequencies, locations, times, power levels, and equipment, among other 

things. We recently reported that both FCC’s and NTIA’s spectrum 

databases may contain incomplete and inaccurate data.20 We reported 

that a substantial number of surveyed users of FCC’s largest and most 

accessed license database, the Universal Licensing System, said that 

inaccurate and missing data hindered their use of the system to a great or 

moderate extent.21 NTIA collects basic, descriptive information on federal 

spectrum use, such as agency name, frequency, and location, in its 

Government Master File, and relies on agencies to evaluate and report 

their own current and future spectrum needs, even though agencies have 

not always provided accurate information on their spectrum use, which 

could be useful in coordinating sharing arrangements.22

 

20In November 2011, we reported on FCC’s Universal Licensing System, Consolidated 

Database System, International Bureau Filing System, and Experimental Licensing 

System. See GAO, Commercial Spectrum: Plans and Actions to Meet Future Needs, 

Including Continued Use of Auctions, 

Further, federal 

agency spectrum managers told us that agencies have not been asked to 

GAO-12-118 (Washington, D.C.: Nov. 23, 2011). In 

April 2011, we reported on NTIA’s Government Master File database. See GAO, 

Spectrum Management: NTIA Planning and Processes Need Strengthening to Promote 

the Efficient Use of Spectrum by Federal Agencies, GAO-11-352 (Washington, D.C.: Apr. 

12, 2011). 

21GAO-12-118. 

22GAO-11-352. 

Users May Be Unable to 

Easily Identify Spectrum 

Available for Sharing
 

Page 16 GAO-13-7 Spectrum Sharing

regularly update their spectrum plans, in which they were required to 

include an accounting of spectrum use. Federal agencies were directed to 

submit spectrum plans to NTIA and provide updates every 2 years.23

NTIA is developing a new data system that officials believe will provide 

more robust data that will enable more accurate analysis of spectrum 

usage and potential interference. The new system may in turn identify 

more sharing opportunities. NTIA officials plan for the new Federal 

Spectrum Management System (FSMS) to house more detailed data 

about agencies’ spectrum usage than the current Government Master 

File, including times of use, power levels, and equipment, among other 

information not currently collected. FSMS is scheduled to be operational 

in fiscal year 2014. However, the data will only be available to IRAC 

members and will not be publicly available.

Since 2008, NTIA has ceased requesting those updates and has put its 

strategic planning initiatives on hold because of limited resources.

Legislation has been introduced to try to address the lack of publicly 

available data on spectrum usage broadly.24 The legislation would require 

in part that FCC, in consultation with NTIA and the White House Office of 

Science and Technology, prepare a report for Congress that includes an 

inventory of each radio spectrum band they manage. The inventory is 

also to include data on the number of transmitters and receiver terminals 

in use, if available. Other technical parameters that allow for more 

specific evaluation of how spectrum can be shared will also be 

inventoried, including coverage area, receiver performance, location of 

transmitters, percentage and time of use, and a list and described use of 

unlicensed devices authorized to operate in the band. However, experts 

and federal officials we contacted told us that there may be some 

limitations to creating such an inventory. For instance, measuring 

spectrum usage can be difficult because it can only be accomplished on a 

small scale and technologies to measure or map widespread spectrum 

usage are not yet available.25

 

23See, President’s Memorandum on Improving Spectrum Management for the 21st 

Century, 49 Weekly Comp. Pres. Doc. 2875 (Nov. 29, 2004). 

Additionally, FCC and NTIA officials told us 

that information on some federal spectrum bands may never be made 

24S. 455, § 3, 112th Cong. (2011).

25The Department of Defense’s Defense Advanced Research Projects Agency is working 

on frequency mapping, as discussed later in this report.
 

Page 17 GAO-13-7 Spectrum Sharing

publicly available because of the sensitive or classified nature of some 

federal spectrum use.

Federal advisors and experts we spoke with identified several options that 

could provide incentives and opportunities for more efficient spectrum use 

and sharing, by federal and nonfederal users, which include, among 

others: (1) assessing spectrum fees; (2) expanding the availability of 

unlicensed spectrum; (3) identifying federal spectrum that can be shared 

and promoting sharing; (4) requiring agencies to give more consideration 

to sharing and efficiency; (5) improving and expediting the spectrumsharing process; and (6) increasing the federal focus on research, 

development and testing of technologies that can enable sharing, and 

improve spectral efficiency. We have previously reported that to improve 

spectrum efficiency among federal agencies, Congress may wish to 

consider evaluating what mechanisms could be adopted to provide better 

incentives and opportunities for agencies to move toward more efficient 

use of spectrum, which could free up some spectrum allocated for federal 

use to be made available for sharing or other purposes.26

Several advisory groups and industry experts, including those we 

interviewed, have recommended that fees be assessed based on 

spectrum usage. As previously mentioned, with the exception of fees for 

frequency assignments, federal users incur no costs for using spectrum 

and have few requirements for efficient use. As s result, federal users 

may have little incentive to share spectrum assigned to them with 

nonfederal users or identify opportunities to use it more efficiently—

except to the extent that sharing or more efficient use helps them achieve 

their mission requirements. In 2011, the CSMAC Incentives 

Subcommittee recommended that NTIA and FCC study the 

implementation of spectrum fees and solicit input from both federal and 

nonfederal users that might be subject to fees.27

 

26GAO, 2012 Annual Report: Opportunities to Reduce Duplication, Overlap and 

Fragmentation, Achieve Savings, and Enhance Revenue, 

The National Broadband 

Plan has also recommended that Congress consider granting FCC and 

NTIA authority to impose fees on unauctioned spectrum license holders—

GAO-12-342SP (Washington, 

D.C.: Feb. 28, 2012).

27CSMAC Incentives Subcommittee Final Report. 

Incentives and 

Opportunities to 

Share Spectrum 

Could Be Expanded

Assessing Spectrum Fees
 

Page 18 GAO-13-7 Spectrum Sharing

such as TV broadcasters and public safety entities—as well as 

government users.28 Fees could help to free spectrum for new uses, since 

licensees that use spectrum inefficiently may reduce their holdings or 

pursue sharing opportunities once they bear the opportunity cost of letting 

their spectrum remain fallow or underused. FCC officials told us that they 

have proposed spectrum usage fees at various times including in FCC’s 

most recent congressional budget submission and have requested, but 

have yet to receive, legislative authority to implement such a program.29

While noting the benefits of spectrum fees, the CSMAC Incentives 

Subcommittee report also notes specific concerns about the impact of 

spectrum fees on government users. For instance, some CSMAC 

members expressed concern that fees do not fit into the federal annual 

appropriations process and that new appropriations to cover fees are 

neither realistic nor warranted in the current budget environment. Other 

members suggested that fees will have no effect because agencies will 

be assured additional funds for their spectrum needs. Similarly, the 

National Broadband Plan notes that a different approach to setting fees 

may be appropriate for different spectrum users, and that a fee system 

must avoid disrupting public safety, national defense, and other essential 

government services that protect human life, safety, and property.30

To address some of the concerns regarding agency budgets, the recent 

PCAST report recommended the use of a “spectrum currency” process to 

promote spectrum efficiency. Rather than using funds to pay for 

spectrum, federal agencies would each be given an allocation of synthetic 

currency that they could use to “buy” their spectrum usage rights. Usage 

fees would be set based on valuations of comparable private sector uses 

for which the market has already set a price. Agencies would then have 

an incentive to use their assignments more efficiently or share spectrum. 

In the PCAST proposal, agencies would also not bear the costs of making 

spectrum available to others for sharing, because they could be 

 

28 In 2010, an FCC task force issued the National Broadband Plan. Federal 

Communications Commission, Connecting America: The National Broadband Plan, p. 83, 

Recommendation 5.6, (Mar. 16, 2010). 

29Federal Communications Commission, Fiscal Year 2013 Budget Estimates Submitted to 

Congress, p15 (Washington, D.C.: February 2012).

30 The National Broadband Plan, p83, Recommendation 5.6 (Mar. 16, 2010).
 

Page 19 GAO-13-7 Spectrum Sharing

reimbursed for their investments that made sharing possible from a 

proposed Spectrum Efficiency Fund.31

Internationally, some regulatory agencies have moved forward with 

charging market based rates for spectrum. Officials in two of the countries 

we spoke with said that the regulatory agency in their country collects 

user fees for government-agency spectrum use that reflect the 

opportunity cost of spectrum and serve as a means to encourage greater 

efficiency. For instance, the Australian Communications and Media 

Authority assesses two types of license fees for devices: (1) 

administrative charges to recover the direct costs of spectrum 

management and (2) annual license taxes to recover the indirect 

government costs of spectrum management. Officials suggested that

license fees provide incentives for efficient use. Similarly, the Office of 

Communications in the United Kingdom uses a concept known as 

Administered Incentive Pricing (AIP) to set charges for spectrum holdings 

to reflect the value of the spectrum and to promote efficient use. Officials 

in these countries told us that the fee structure also encourages agencies 

to seek more opportunities to share spectrum. For example, in response 

to the United Kingdom’s AIP system, one ministry conducted a study of 

which spectrum bands could be shared or, if not in full use, released for 

use by others. The ministry identified at least five bands to share and 

released additional bands because the cost associated with retaining 

those rights was not economically feasible for intermittent use. As a 

result, the ministry relinquished its rights to those underused bands.

According to stakeholders, unlicensed use is a valuable complement to 

licensed use and more spectrum could be made available for unlicensed 

use. Spectrum for unlicensed use can be used efficiently and for high 

value applications, like Wi-Fi, for example.32

 

31The PCAST recommended that the existing Spectrum Relocation Fund be redefined as 

a revolving Spectrum Efficiency Fund that reimburses federal agencies for investments in 

spectrum sharing and efficiency.

While FCC has generally 

32Wi-Fi networks can permit multiple computing devices in each discrete location to share 

a single wired connection to the Internet, thus efficiently sharing spectrum. Wi-Fi 

technologies are also being used to relieve network congestion. One report suggests that 

major wireless carriers, even with their large portfolios of exclusive-use, licensed 

spectrum, often rely on Wi-Fi infrastructure to offload traffic from their networks in 

congested areas, as much as 21 percent by some accounts.

Expanding Unlicensed Use
 

Page 20 GAO-13-7 Spectrum Sharing

relied on auctions to license spectrum, which over the years have 

generated billions in dollars of revenue for the United States Treasury, 

FCC is attempting to make more unlicensed spectrum available in the 

hope of fueling innovation and economic growth. Increasing the amount 

of spectrum available for unlicensed use allows more users to share 

spectrum without going through lengthy negotiations and interference 

mitigations, and also promotes more experimentation and innovation. To 

access exclusively licensed spectrum, users must enter into sharing 

agreements with the license holder sand negotiate access each time they

wish to use that spectrum. By contrast, when spectrum is available for 

unlicensed purposes, such negotiation is generally not needed and, 

according to some experts, may lead to more widespread 

experimentation and the development of innovative technologies. 

More recently, FCC has provided unlicensed access to additional 

spectrum, known as TV “white spaces,” to help address spectrum 

demands.33 The white spaces refer to the buffer zones that FCC provided 

between the television broadcasters to mitigate unwanted interference 

between adjacent stations. In the TV white space rules, the buffer zones 

are no longer needed, and FCC approved the previously unused 

spectrum for unlicensed use. To identify available white space spectrum, 

devices must access a database that responds with a list of the 

frequencies that are available for use at the device’s location.34 As an 

example, one local official explained that the City of Wilmington, North 

Carolina, uses TV white space spectrum to provide a network of public 

Wi-Fi access and public-safety surveillance functions. However, some 

experts have noted that the use of white space for rural areas holds more 

promise than large, dense urban areas because the sheer number of TV 

stations and higher usage in those areas makes use of the white spaces 

more challenging.

 

33In the Matter of Unlicensed Operation in the TV Broadcast Bands, 27 FCC 3,692 (Apr. 5, 

2012). 

34To date, FCC has designated two administrators to locate available white space 

spectrum for users of unlicensed devices, Spectrum Bridge and Telcordia Technologies. 

Devices must operate only on those channels designated by the administrator. 
 

Page 21 GAO-13-7 Spectrum Sharing

FCC and NTIA have noted the importance of sharing federal spectrum as 

a means to address spectrum demand. FCC’s Chairman recently said 

that it has become increasingly harder to find free and clear blocks of 

spectrum.35 The Chairman further said that it would be counterproductive 

to be limited to the choices of reallocation or nothing and that it may be 

the case that in some bands, sharing could allow access to spectrum that 

might otherwise take years and be costly to make available to other 

users. As we previously mentioned, in 2010, the President directed 

federal agencies to clear 500 MHz of spectrum for nonfederal uses by 

2020.36 In response to this directive, NTIA identified bands to evaluate for 

repurposing. For example, an interagency group was formed to determine 

the viability of accommodating commercial wireless broadband in the 

1755-1850 MHz band.37 However, the evaluation found that clearing this 

95 MHz band may take 10 years, cost $18 billion, and cause significant 

disruption. Furthermore, some federal systems could remain in the band 

indefinitely. To support NTIA’s effort regarding this band, FCC recently 

granted special temporary authority for T-Mobile to conduct tests to 

explore sharing between commercial wireless services and federal 

systems operating in the 1755-1780 MHz band.38 NTIA has also noted 

that the federal government must ensure effective spectrum use and push 

for sharing and other innovative uses wherever possible.39

 

35FCC Chairman Julius Genachowski, Prepared Remarks to International CTIA Wireless

(May 8, 2012). 

Further, it is 

critical that agencies participate in identifying strategies for more efficient 

use of spectrum, including sharing it, while maintaining essential federal 

missions. For example, NTIA asked CSMAC to advise on what kinds of 

sharing are workable in the long term. Consequently, CSMAC is 

reviewing options to analyze the impact federal systems remaining in the 

band might have on future commercial uses, and the sharing conditions 

that might be required to protect incumbent systems.

36Unleashing the Wireless Broadband Revolution, 75 Fed. Reg. 38,387 (June 28, 2010). 

37U.S. Department of Commerce, An Assessment of the Viability of Accommodating 

Wireless Broadband in the 1755-1850 MHz Band (March 2012).

38Special license granted to T-Mobile License LLC effective August 13, 2012.

39United States Department of Commerce, Plan and Timetable to Make available 500 

Megahertz of Spectrum available for Wireless Broadband (October 2010). 

Identifying Federal 

Spectrum That Can Be 

Shared and Promoting 

Sharing
 

Page 22 GAO-13-7 Spectrum Sharing

Recent PCAST recommendations could also create opportunities for 

nonfederal users to share 1,000 MHz of spectrum previously occupied 

only by federal users. Out of concern that additional clearing of federal 

users from spectrum is not sustainable, PCAST recently recommended 

that the President issue a new policy memorandum calling for the federal 

government to immediately identify 1,000 MHz of federal spectrum for 

sharing with nonfederal users.40 To facilitate sharing this spectrum, 

PCAST also recommended that FCC and NTIA implement a federal 

spectrum access system that includes data on when and where federal 

users could allow access to fallow spectrum. Such a system could help 

streamline the regulatory processes involved in sharing that we discussed 

earlier. However, PCAST acknowledged that implementing the structure 

they recommended will not be easy and could take a long time. Moreover, 

some experts and industry stakeholders suggest that sharing 1,000 MHz 

of federal spectrum may be no easier or less costly than previous efforts 

to vacate half that amount, given the barriers to sharing that exist.

In 2011, the Office of Management and Budget (OMB) updated its

guidance to federal agencies on preparing the fiscal year 2013 budget by 

asking agencies to consider the economic value of spectrum when 

developing their economic justifications for procuring new equipment.41

 

40Report to the President; Realizing the Full Potential of Government-held Spectrum to 

Spur Economic Growth. 

The guidance noted that spectrum should generally not be considered a 

free resource, but rather should be considered to have value. Therefore, 

budget requests for systems that require spectrum should include the 

evaluation of alternative systems or methods that reduce spectrum 

needs, such as spectrum sharing. In January 2011, CSMAC reported that 

the focus of this process had been on capital planning. The Committee 

stated that it believed it would be more useful to focus on ensuring that 

agencies give more consideration to trade-offs in spectrum use in their 

management processes. They also said that doing so will likely yield 

greater improvements in overall spectrum management and use. Toward 

that end, with respect to the budget for major spectrum-dependent 

communications systems, the Committee rewrote the circular, 

recommending that agencies specify in their spectrum proposals (a) 

41Office of Management and Budget, Preparation, Submission, and Execution of the 

Budget, Circular No. A–11 (Washington, D.C.: August 2011).

Requiring Agencies to Give 

More Consideration to 

Spectrum Sharing and 

Efficiency
 

Page 23 GAO-13-7 Spectrum Sharing

whether the system will share with other existing systems, (b) the extent 

to which replacement systems will be more spectrally efficient compared 

to the prior system, and (c) that there was consideration of non-spectrum 

dependent or commercial alternatives. The Middle Class Tax Relief and 

Job Creation Act required that OMB implement these recommendations.42

We have also reported that federal agencies generally invest in more 

spectrally efficient technologies when mission needs demand it, not 

according to any underlying, systematic consideration of spectrum 

efficiency.43 As a result, we recommended that FCC and NTIA jointly 

develop accepted models and methodologies to assess the impact of new 

technologies on overall spectrum use and that NTIA determine how to 

provide incentives to agencies to use spectrum more efficiently.44

FCC and NTIA have taken some actions to potentially reduce the amount 

of time and even the need for some potential rulemakings associated with 

spectrum sharing, but stakeholders and experts we interviewed 

suggested that more could be done to expedite the process. NTIA also 

encourages communication between federal and nonfederal users 

regarding sharing plans to deal with potential interference and other 

technical issues early in the process. These communications are 

important to provide certainty to nonfederal users about the availability of 

shared spectrum while also ensuring that critical federal operations are 

protected.

Stakeholders suggested that NTIA and FCC could do more to streamline 

or automate their processes, and that more complete databases of 

spectrum use, as discussed earlier, could help potential sharing entities 

identify opportunities. Some experts argued for FCC to shift from a 

“command and control” approach for spectrum management to a 

regulatory approach that was more flexible and adaptable to new 

technologies. Others argue that the process is further slowed down and 

 

4247 U.S.C. § 1456.

43GAO, Spectrum Management: Better Knowledge Needed to Take Advantage of 

Technologies That May Improve Spectrum Efficiency, GAO-04-666 (Washington, D.C.: 

May 2004).

44In response to the recommendation, FCC and NTIA jointly prepared the Federal 

Strategic Spectrum Plan which established a test bed and models to measure the impact 

of new technologies on spectrum use.

Improving and Expediting 

the Spectrum-Sharing 

Process
 

Page 24 GAO-13-7 Spectrum Sharing

complicated because two regulatory agencies are involved as opposed to 

a single agency, as is the case in other countries, and other industries.

CSMAC also reported that FCC and NTIA could do more to streamline 

the sharing approval process. For example, a common frustration is that a 

nonfederal entity seeking to share federal spectrum is unable to precisely 

follow the status of its spectrum sharing application once it is filed with the 

FCC. Further, it is not transparent in the experimental licensing process 

on the FCC website when FCC transmits applications to NTIA, when 

NTIA responds to FCC, and whether that response contains questions to 

which the applicant must respond to progress the application. On the 

NTIA side, IRAC’s Frequency Assignment Subcommittee established a 

review period of approximately nine days to respond with concurrence or 

concerns regarding an application. NTIA’s website provides some 

information regarding the status of an application in the IRAC process; 

however, the information is very generic and the nonfederal applicant has 

no means to obtain information as to why its request was tabled or to 

engage directly with the concerned parties. For applicants to more 

proactively engage FCC regarding concerns or other actions, CSMAC 

recommended that there be a public tracking capability that allows an 

FCC applicant to readily identify when FCC sent the application to NTIA, 

when NTIA responded, and whether NTIA had specific questions 

regarding the merits or technical components of the application. 

Regardless, any such changes to how spectrum is currently managed 

and regulated would need to be carefully studied with respect to potential 

benefits and costs.

Several technological advances promise to make sharing easier, but are 

still at early stages of development and testing. For example, various 

spectrum users and experts we contacted mentioned the potential of 

dynamic spectrum access technology. If made fully operational, dynamic 

spectrum access technology will be able to sense available frequencies in 

an area and jump among frequencies to seamlessly continue 

communication as the user moves geographically through spectrum 

bands. According to experts and researchers we spoke with, progress 

has been made but there is no indication of how long it will be before this 

technology is fully deployable. Similarly, current fourth generation (4G) 

Long Term Evolution (LTE) technologies promise the ability to facilitate 

channel sharing as well as much faster data transfer rates over time, 

which could also potentially free frequencies more quickly for use by 

others. However, experts we talked to could not predict how long it will be 

before data networks reach international 4G transmission standards and 

Increasing the Federal 

Focus on Research, 

Development and Testing
 

Page 25 GAO-13-7 Spectrum Sharing

thus, maximize spectral efficiency. Such new technologies can obviate or 

lessen the need for extensive regulatory procedures to enable sharing 

and can open up new market opportunities for wireless service providers. 

If a secondary user or sharing entity employs these technologies, the 

incumbent user or primary user would theoretically not experience 

interference, and agreements and rulemakings that are currently needed 

may not be necessary to enable sharing.

Although industry participants indicated that extensive testing under 

realistic conditions is critical to conducting basic research on spectrum 

efficient technologies, we found that only a few companies are involved in 

such research and may experience challenges in the testing process. 

Companies tend to focus technology development on current business 

objectives as opposed to conducting basic research that may not show an 

immediate business return. For example, NTIA officials told us that one 

company that indicated it would participate in NTIA’s dynamic spectrum 

access-testing project removed its technologist from the testing effort to a 

project more closely related to its internal business objectives. 

Furthermore, some products are too early in the development stage to 

even be fully tested. For example, NTIA officials said six companies 

responded to NTIA’s invitation to participate in the previously mentioned 

dynamic spectrum access-testing project. However, three handsets were 

received for the testing, and one of those did not work as intended. Other 

companies that responded told NTIA that they only had a concept and 

were not ready to test an actual prototype.

We have previously reported that the federal government has a key role 

in performing or otherwise encouraging research that the private industry 

would not do on its own.45 With respect to research and development on 

spectrum sharing and spectrum efficiency, we found that FCC and NTIA 

are involved in creating test beds and other opportunities for research and 

development.46

 

45GAO, Research and Development: Lessons learned from Previous Research Could 

Benefit FreedomCAR Initiative, 

For example, when FCC proposed a rulemaking to 

improve its experimental license program in November 2010, it invited 

comments on a number of ideas including the need to identify locations 

for test beds, where new technologies could be tested before being 

GAO-02-810T (Washington, D.C.: June 2002).

46A spectrum test bed consists of specific segments of spectrum set aside to test 

technologies, services or related techniques. 
 

Page 26 GAO-13-7 Spectrum Sharing

introduced to the market and frequency bands where FCC might provide 

increased flexibility to conduct experiments. Further, FCC is seeking to 

establish provisions that encourage the exploration of new technologies, 

including technologies that would facilitate spectrum sharing. To expand 

testing opportunities, PCAST recommended that real-world test services 

be provided to test federal and public-safety frequency bands. Similarly, 

the Wireless Spectrum Research and Development’s Senior Steering 

Group is conducting workshops regarding the development of a national 

wireless test environment.47 However, spectrum users told us that even 

though they understand the benefits of testing and development, they are 

reluctant to allow testing in their spectrum because of the potential for 

harmful interference. As previously mentioned, NTIA also has a pilot test 

bed program to evaluate dynamic spectrum access and technology for 

spectrum sharing in land mobile radio bands, but the program is in the 

early stages and requires additional access to spectrum for testing to be 

fully implemented.48

The Department of Defense—the federal agency with the largest number 

of spectrum assignments—is also involved in researching and developing 

new spectrum technologies, although they are still in the early stages. 

The Department’s Defense Advanced Research Projects Agency 

(DARPA) has several such efforts under way. For example, unlike 

existing databases that only provide limited, descriptive frequency 

assignment information, DARPA’s Advanced Radio Frequency Mapping 

program seeks to provide real-time awareness of spectrum use across 

frequency, geography, and time. With this information, spectrum 

managers and automatic spectrum allocation and management systems 

could operate more efficiently through improved interference mitigation. 

However, agency officials told us that this technology is at the basic 

research level and years away from market readiness. Also, in the 

beginning phases, the Communications Under Extreme Radio Frequency 

Spectrum Conditions program plans to address spectrum use and 

interference mitigation in a congested communications environment. 

According to DARPA officials, the program will work to develop 

 

47Formed as result of the President’s 2010 memorandum, Unleashing the Wireless 

Broadband Revolution, the Wireless Spectrum Research and Development’s Senior 

Steering Group coordinates spectrum-related research and development activities across 

the federal government, and helps identify gaps in the government’s research and 

development portfolio with respect to spectrally efficient technologies.

48Frequencies in the 410-420 MHz land-mobile-radio band will be used in this test bed.
 

Page 27 GAO-13-7 Spectrum Sharing

interference mitigation technologies (especially for jamming),49

Recent federal advisory committee recommendations and international 

examples also emphasize the importance of funding and providing 

incentives for research and development endeavors. For example, to 

promote research in efficient technologies, PCAST recommended that (1) 

the Research and Development Wireless Innovation Fund

interference tolerance, and higher spectrum utilization.

50 release funds 

for this purpose and (2) the current Spectrum Relocation Fund be 

redefined as the Spectrum Efficiency Fund.51 This adjustment would allow 

federal agencies to be reimbursed for general investments in improving 

spectrum sharing. PCAST also recently suggested that a partnership 

between the federal government and the private sector is the best 

mechanism to ensure optimal use of federal spectrum and related 

spectrum research and testing.52 Similarly, CSMAC recommended the 

creation of a Spectrum Innovation Fund. Unlike the Spectrum Relocation 

Fund, which is strictly limited to the actual costs incurred in relocating 

federal systems from auctioned spectrum bands, the Spectrum Innovation 

Fund could also be used for spectrum sharing and other opportunities to 

enhance spectrum efficiency.53 To deal with similar problems, the 

Canadian government instituted tax credits for research and development 

efforts by Canadian wireless companies, and required wireless 

companies to commit 2 percent of all revenues toward research and 

development activities related to spectrum.

 

49FCC defines jamming as illegal radio frequency transmissions that are designed to 

block, jam, or otherwise interfere with authorized radio communications. 

50The Wireless Innovation Fund is a part of the 2012 Payroll tax agreement for spectrum 

research and development. It will initially be a $100 million fund at the National Institute of 

Standards and Technology. The fund will receive an additional $200 million after approved 

auction income has been secured.

51The Spectrum Relocation Fund exists for the purpose of reimbursing agencies for the 

actual costs incurred in relocating or sharing federal spectrum. NTIA Authorization Act, 

§ 118, 47 U.S.C. § 928.

52Report to the President; Realizing the Full Potential of Government-held Spectrum to 

Spur Economic Growth. 

53CSMAC Incentives Subcommittee Final Report.
 

Page 28 GAO-13-7 Spectrum Sharing

As the demand for and use of spectrum continues to increase, federal 

and nonfederal users will need to be more cognizant of how efficiently 

spectrum is used. Sharing spectrum is one way to use spectrum more 

efficiently and make more spectrum available. While a number of barriers 

exist to sharing spectrum—such as incompatible uses, potentially 

prohibitive costs, and cumbersome regulatory processes—it is clear that 

first and foremost, users currently lack incentives to share the spectrum 

that is assigned or licensed to them. To address the incentive problem, 

spectrum experts, federal advisory groups, and others have made 

recommendations but have also identified implementation problems 

associated with different options. First, we agree with experts that 

spectrum usage fees should be given further consideration. We 

previously reported that incentive-based fees are designed to promote the 

efficient use of spectrum by compelling users to recognize the value to 

society of the spectrum that they use. Yet, designing a fee system is 

fraught with numerous obstacles and challenges, such as how such fees 

should be incorporated into agency budgets and the appropriations 

process in order to create the right incentives. A full evaluation of the 

potential benefits and impacts of implementing a fee structure would be a 

potential step in identifying the most prudent and effective approach. 

Second, because new technologies that could better facilitate sharing are 

in some cases years from market readiness, spectrum users could be 

encouraged to dedicate more resources to research and development. 

Additionally, users need spectrum access for testing new technologies. If 

there are continued limitations to accessing spectrum for testing, it may 

be impossible to validate technologies under realistic conditions, further 

delaying the availability of these technologies to users and the opening of 

new market opportunities and economic growth. Third, users have 

expressed concern about the timeliness of FCC and NTIA spectrumsharing processes. If these processes continue to be lengthy and 

unpredictable, federal and nonfederal users may continue to be reluctant 

to share spectrum. As the debate about these options continues, it is 

clear that more information is needed to further the understanding and 

discussion about which incentives and opportunities will be the most 

feasible and effective toward promoting sharing as a viable solution to 

address increasing spectrum demand.

To better identify the most feasible incentives to promote spectrum 

efficiency and sharing, we recommend that the NTIA Administrator and 

the FCC Chairman jointly take the following three actions:

Conclusions

Recommendations for 

Executive Action
 

Page 29 GAO-13-7 Spectrum Sharing

• Report their agencies’ views and conclusions regarding spectrum 

usage fees to the relevant congressional committees, specifically with 

respect to the merits, potential effects, and implementation challenges 

of such a fee structure, and what authority, if any, Congress would 

need to grant for such a structure to be implemented. 

• Based on the findings of current research and development efforts 

under way, determine how the federal government can best promote 

federal and nonfederal investment in the research and development of 

spectrally efficient technologies, and whether additional spectrum is 

needed for testing new spectrum efficient technologies. 

• Evaluate regulatory changes, if any, that can help improve and 

expedite the spectrum sharing process.

We provided a draft of this report to the Department of Commerce and 

FCC for review and comment. In response to our draft report, Commerce 

and FCC provided written comments, which are reprinted in appendix II 

and III, respectively. The agencies also provided technical corrections to 

the draft report, which we incorporated as appropriate. In summary, 

Commerce concurred with our findings, but believes that activities 

completed or under way by NTIA and FCC satisfy the recommendations 

contained in our draft report. In its written comments, FCC noted that the 

agency was pursuing the goals outlined in the National Broadband Plan, 

and highlighted several actions it is taking to promote more shared 

access to spectrum. 

In our draft report, we included four recommendations. The first 

recommendation was that NTIA and FCC jointly examine the merits and 

challenges associated with implementing spectrum usage fees. 

Commerce noted that the issue was examined by the CSMAC in 2010 

and 2011 and that consensus could not be reached regarding the 

imposition of such fees. Moreover, the agency states that further study is 

unlikely to resolve the issues. We agree that implementation of spectrum 

usage fees or a similar structure that can provide users with greater 

incentive to efficiently use or share spectrum raises several difficult 

questions, such as authority to implement a new fee structure and 

ensuring that federal operations are not disrupted. We also agree that 

further study may not resolve these issues. Nevertheless, our findings 

suggest that additional incentives are still needed for users to seek out 

more efficient ways of using spectrum, such as sharing, and that 

Congress could benefit from more information to fully understand the 

implications of a fee structure. Therefore, we altered our recommendation 

to state that NTIA and FCC, rather than initiate additional study on the 

issue, should provide Congress with the agencies’ views and conclusions 

Agency Comments 

and Our Evaluation
 

Page 30 GAO-13-7 Spectrum Sharing

regarding the merits, potential effects, and implementation challenges of 

such a fee structure, and authorities that Congress would need to grant 

that such a structure be implemented. We believe such actions would 

help provide members of Congress with information they could use to 

evaluate any proposed fee structure or other proposed incentive 

schemes.

Our second recommendation was that FCC and NTIA jointly study 

whether spectrum should be repurposed and made available for 

unlicensed use. However, in written comments the agencies identified 

NTIA’s and FCC’s recent efforts to identify spectrum for repurposing, 

which have focused on allowing unlicensed users to share the spectrum. 

Consequently, we removed that recommendation from our final report.

Our draft report also recommended that the agencies jointly study (1) 

actions that could help spur research and development and (2) regulatory 

changes that might improve the spectrum-sharing process. Commerce 

stated that NTIA and FCC already have efforts under way in these areas 

that fulfill the goals of these recommendations and that additional study is 

unnecessary. We acknowledge throughout the report that NTIA and FCC 

have activities under way in these areas, some of which were initiated 

during the course of our review. The intent of our recommendations was 

not to displace these activities with additional study, but rather to support 

these actions, and to encourage the agencies to take further steps to 

enable real world testing of spectrum-sharing technologies and to 

streamline and improve the regulatory processes that enable spectrum 

sharing. We revised our draft recommendations to clarify that we are 

encouraging NTIA and FCC to take further actions in these areas, as 

opposed to further study, and we will continue to monitor the agencies’ 

efforts in these areas.

In addition to Commerce and FCC, we also provided the Departments of 

Defense, Homeland Security, Interior, Justice, Transportation, and 

Treasury the opportunity to comment on segments of the report that 

pertain to the data and information they provided. Except for the 

Department of Transportation, which did not provide any comment, the 

agencies verified the key facts we obtained from them and provided 

technical corrections to the draft report, which we incorporated as 

appropriate.

We are sending copies of this report to the Secretary of Commerce, the 

Chairman of the Federal Communications Commission, and appropriate 
 

Page 31 GAO-13-7 Spectrum Sharing

congressional committees. In addition, the report will be available at no 

charge on GAO’s website at http://www.gao.gov. If you or members of 

your staff have any questions about this report, please contact me at 

(202) 512-2834 or goldsteinm@gao.gov. Contact points for our Offices of 

Congressional Relations and Public Affairs may be found on the last page 

of this report. Major contributors to this report are listed in appendix IV.

Mark L. Goldstein

Director, Physical Infrastructure
Appendix I: Federal Agencies, Nonfederal 

Spectrum Users and Experts Interviewed 

Regarding Spectrum Sharing

Page 32 GAO-13-7 Spectrum Sharing

• Department of Commerce

• National Oceanic and Aviation Administration

• National Telecommunications and Information Administration

• Department of Defense

• Army 

• Air Force

• Defense Advanced Research Projects Agency

• Defense Information Systems Agency

• Navy

• Department of Homeland Security

• Wireless Service Spectrum Management Office

• Customs and Border Patrol

• Department of the Interior

• Department of Justice

• Department of Transportation

• Department of the Treasury

• Treasury Inspector General for Tax Administration

• Federal Communications Commission

• City of Wilmington, North Carolina

• Google

• Metro PCS

• Microsoft

• Shared Spectrum (a spectrum sharing solutions company)

• Spectrum Bridge (a spectrum user, and also a spectrum sharing 

solutions company)

• Sprint 

• T-Mobile

• United States Cellular

• Verizon 

Appendix I: Federal Agencies, Nonfederal 

Spectrum Users and Experts Interviewed 

Regarding Spectrum Sharing

Selected Interdepartment 

Radio Advisory 

Committee Member 

Agencies

Nonfederal Spectrum 

Users
Appendix I: Federal Agencies, Nonfederal 

Spectrum Users and Experts Interviewed 

Regarding Spectrum Sharing

Page 33 GAO-13-7 Spectrum Sharing

Table 1: Subject Matter Experts Interviewed

Name Institutiona

Phillippe Aubineau International Telecommunications Union

Coleman D. Bazelon The Brattle Group

Michael Christensen Industry Canada

Andrew W. Clegg National Science Foundation

Larry Downes Spectrum consultant and author

Pierre de Vries University of Colorado

Gary M. Epstein Aspen Institute, International Digital Economy Accords

Tomas E. Gergely National Science Foundation

Thomas W. Hazlett George Mason University School of Law

Stephen Jones Office of Communications, U.K.

William Lehr Massachusetts Institute of Technology

Nevio Marinelli Australian Communications and Media Authority

Preston F. Marshall University of Southern California

Geoff McMillen Australian Communications and Media Authority

Linda K. Moore Congressional Research Service

Jon M. Peha Carnegie Mellon University

Jerry Pi Samsung 

Ravi Prakash University of Texas, Dallas Texas

Francois Rancy International Telecommunications Union

Richard Reaser CSMAC 

Raytheon

Greg Rosston Stanford Institute for Economic Policy Research

Jennifer A. Warren Lockheed Martin

Chris Woolford Office of Communications, U.K.

Source: GAO.

a

We interviewed experts as individuals, not as representatives of any institution. We provide 

information on institutions to help readers identify experts. 
Appendix II: Comments from the Department 

of Commerce

Page 34 GAO-13-7 Spectrum Sharing

Appendix II: Comments from the Department 

of Commerce
Appendix II: Comments from the Department 

of Commerce

Page 35 GAO-13-7 Spectrum Sharing
Appendix II: Comments from the Department 

of Commerce

Page 36 GAO-13-7 Spectrum Sharing
Appendix III: Comments from the Federal 

Communications Commission 

Page 37 GAO-13-7 Spectrum Sharing

Appendix III: Comments from the Federal 

Communications Commission
Appendix III: Comments from the Federal 

Communications Commission 

Page 38 GAO-13-7 Spectrum Sharing
Appendix IV: GAO Contact and Staff 

Acknowledgments

Page 39 GAO-13-7 Spectrum Sharing

Mark L. Goldstein, (202) 512-2834 or goldsteinm@gao.gov

In addition to the contact person named above, Andrew Von Ah 

(Assistant Director), Eli Albagli, Amy Abramowitz, Michael Clements, 

Andy Clinton, David Goldstein, Brian Hartman, Bert Japikse, Elke 

Kolodinski, Jean McSween, Erica Miles, Sally Moino, Joshua Ormond, 

Amy Rosewarne, Hai Tran, and Jarrod West made key contributions to 

this report.

Appendix IV: GAO Contact and Staff 

Acknowledgments 

GAO Contact

Staff 

Acknowledgments

(543292)
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