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OCR for page 1
1
Summary of Remarks Made by Forum Panelists
FEDERAL SPECTRUM USERS: DEFENSE, JUSTICE, TRANSPORTATION, AND
AVIATION
In Session 1A, panelists from several federal agencies1 discussed spectrum management
from the perspective of the defense, homeland security, justice, transportation, and aviation
missions. Speakers made a number of points emphasizing the special nature of federal spectrum
use, noting that
· Many federal spectrum applications--such as defense, safety-of-life operations for
commercial aviation, and law enforcement and other public safety uses--require very high
reliability and interoperability.
· Some federal uses of spectrum are tied to nongovernmental users, which complicates
efforts to modernize wireless systems. For example, the Federal Aviation Administration (FAA)
cannot easily change some of its services because the costs of new equipment would fall on
airlines and pilots.
· Technology changes must often be carefully coordinated to address interdependencies
among systems and to align spectrum use with both U.S. and international spectrum allocations.
· New demands for spectrum continue to emerge in the federal government. For
example, the Intelligent Vehicle Initiative, which is headed by the National Highway Traffic
Safety Administration and the Federal Highway Administration and carried out in partnership
with the automobile industry, aims to create a wireless alert system to warn drivers of changing
road conditions. Implementation of this and other new transportation systems will depend, in
part, on the availability of spectrum.
Regarding the efficiency of federal spectrum use, the panelists noted the following:
· Federal spectrum allocation and assignment processes provide greater flexibility than
does the process of allocating and assigning nonfederal spectrum, which tends to be more service-
and use-specific. This gives federal users greater freedom, for example, to exploit technological
innovation and thus the potential for more efficient use.
1Badri Younes, Department of Defense; David G. Boyd, Department of Homeland Security;
Merri Jo Gamble, Department of Justice; Tyler Duvall, Department of Transportation; and Donald Willis,
Federal Aviation Administration. Biographies for panelists are provided in Appendix C.
1
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2 SUMMARY OF A FORUM ON SPECTRUM MANAGEMENT POLICY REFORM
· Sharing of spectrum among federal users occurs today. For example, the FAA and
Department of Defense (DOD) share spectrum, as the FAA coordinates and authorizes DOD
electronic attack exercises and global positioning jamming activities.
· The Integrated Wireless Network Initiative under development by the Departments of
Justice, Treasury, and Homeland Security is a good example of a program that seeks to provide
interoperability and improve spectral efficiency by building a national land-based, mobile,
encrypted radio network to serve the diverse needs of multiple agencies.
· Spectrum sharing is central to the next generation of global positioning systems, for
which frequency allocations will support both public- and private-sector use.
Comments by panelists regarding possible changes in spectrum management policy
included these:
· Changes to spectrum management policy should balance potential economic benefits
against current and future needs of federal users. Potential commercial benefits should be
weighed against the operational requirements for protecting health and safety. A panelist also
argued that imposing spectrum fees on federal spectrum use would probably not be a useful
mechanism for increasing efficiency. It would, for example, be difficult to determine the value of
spectrum required for safety-of-life missions.
· A national strategic plan should be created to collectively identify how the federal
government could make use of spectrum as efficiently as possible given its operational needs.
Based on input from individual agencies, the plan should identify the mission requirements
driving spectrum needs and identify new technology under consideration by the agencies. The list
of priorities based on federal uses, along with other public and commercial needs, should serve as
a basis for spectrum allocation decisions.
· Automation of federal spectrum administrative processes, which would permit
spectrum use to be monitored and analyzed in real time, would make spectrum management
easier and permit spectrum to be used more effectively and efficiently.
· An integrated testbed should be developed to run trials of new technologies. This
would make it easier for government agencies to explore and adopt new technologies and
determine future possibilities for spectrum sharing.
FEDERAL SPECTRUM USERS: SCIENTIFIC USES
In Session 1B, panelists from the National Aeronautics and Space Administration
(NASA), the National Oceanographic and Atmospheric Administration (NOAA), and the
University of California at Berkeley2 discussed the characteristics of several scientific uses of
federal spectrum and implications for spectrum policy. Outlining the characteristics of several
scientific uses, the panelists observed that
· Services supporting basic research, science missions to outer space, and weather
forecasting require high reliability. Both passive measurements and communications with
spacecraft depend on the detection of very weak signals and are highly susceptible to
interference.
2Scott Pace, National Aeronautics and Space Administration; Richard Barth, National Oceanic
and Atmospheric Administration; Karen St. Germain, National Oceanic and Atmospheric Administration;
and Don Backer, University of California at Berkeley.
OCR for page 3
SUMMARY OF REMARKS MADE BY FORUM PANELISTS 3
· Radio astronomy and the Earth Exploration Satellite Service (EESS) are both passive
spectrum users. Because they are passive observers, they depend on the reception of very weak
signals. Each also has to operate in particular spectral bands dictated by physics--emission and
absorption in the atmosphere in the case of EESS and emissions of elements, molecules, and
stellar objects in the case of radio astronomy.
· EESS data are important for weather forecasting, the development of meteorological
and climate models, and other scientific research. EESS measures changes in the natural thermal
background and is thus very sensitive to interference. Observations are made globally by a
constellation of satellites, which means that spectrum has to be protected worldwide. Because the
signals of interest are very weak, the entire allocated bandwidth is used to squeeze out the best
possible signal-to-noise ratio.
· Radio astronomy data have been critical to improving our understanding of the
universe. The level of tolerable interference for radio astronomy, which measures naturally
occurring radiation from outer space, is roughly 10 orders of magnitude below that of remote-
sensing systems. Operation depends on dedicated spectrum allocations and geographic protection
in the form of radio quiet zones and coordinated operation zones in the vicinity of observatories.
· Satellite-based sensors look down at Earth and thus look at potential interferers, as
opposed to radio telescopes, which can look away from interferers.
· Passive uses raise particular concerns about proposals made in the Federal
Communications Commission's (FCC's) Spectrum Policy Task Force report.3 First, remote-
sensing systems depend on detecting signals significantly weaker than the existing noise floor
level tolerated by commercial systems, raising questions about how one would establish
permissible interference levels in remote-sensing bands. Second, passive users cannot be
detected for the purpose of dynamically controlling access to unused spectrum.
Speakers noted several efforts to make more efficient use of spectrum:
· New generations of satellite systems launched by NOAA and NASA have increased
their bandwidth efficiency. These improvements have been necessary because ongoing
improvements to space sensing equipment have increased the volume of data that must be
transferred from the satellites to ground stations.
· The consolidation of separate polar weather satellite programs operated by NOAA and
DOD into a single system called the National Polar-orbiting Operational Environmental Satellite
System (NPOESS) will improve the spectral efficiency of communications with the satellites in
the system.
Panelists offered a number of comments about future spectrum policy, including
· Making frequency assignments based on good-neighbor policies that aim to place
compatible technologies in adjacent bands of spectrum would be a useful approach.
· The impact on current and future scientific spectrum uses of the cumulative noise floor
level increases that may result from policy changes should be considered.
· Different burdens of proof with respect to safety are, appropriately, applied to safety-
critical services like communication with spacecraft and to normal commercial services. These
differing standards represent an obstacle to shared operation between these services.
3Federal Communications Commission (FCC). 2002. Spectrum Policy Task Force Report, ET
Docket No. 02- 135. FCC, Washington, D.C., November. Available online at
.
OCR for page 4
4 SUMMARY OF A FORUM ON SPECTRUM MANAGEMENT POLICY REFORM
STATE AND LOCAL GOVERNMENT USERS
In Session 2, public safety professionals and state and local officials4 discussed public
safety communication needs as they relate to current and emerging technologies and spectrum
availability. Comments made by panelists include the following:
· The operational needs of public safety (i.e., protection of life and property) cannot be
fully served by today's commercial systems. One reason is coverage. Public safety
communications requires ubiquitous coverage in rural and wilderness areas that are not well-
covered by commercial services. In urban areas, commercial systems do not always reach into
subway systems or interiors of buildings despite the density of base stations. Another reason is
that public safety communications must be able to handle high-volume surges when and where an
emergency occurs, which implies system overprovisioning. Finally, public safety systems must
robustly support one-to-many as well as one-to-one communications.
· Emerging technologies, such as microsensor arrays, mobile robots, radio frequency
identification systems, and augmented reality technology to overlay visual and audio data onto
real-world views for first responders, represent significant opportunities for public safety.
Realizing this potential would require the building of new communications networks, would lead
to significantly greater demand for public safety spectrum, and would heighten tensions between
public safety and commercial uses.
· Interoperability is a major technical and organizational issue. At a technical level it
requires coordination and sharing of information about frequency allocations and technology
standards. At an organizational level, it requires coordination between local first responders,
local elected officials, and state and federal leaders. Current interoperability guidelines produced
by the Department of Homeland Security's SAFECOM program and the National
Telecommunications and Information Administration (NTIA) have been important steps.
· Local government budgets, which provide most of the funding for public safety
communications, are coming under increased pressure. Eighty-three percent of cities are less able
to fund operations today than one year ago, according to a survey by the National League of
Cities.
· Understanding the nature and limitation of current public safety systems is the biggest
challenge facing local elected officials seeking to develop a plan and strategy to mitigate
problems.
· Local elected officials have limited time and technical resources to engage in or stay
abreast of the numerous activities at the federal level examining public safety issues. However, it
is important for local elected officials as well as public safety officials to be involved in these
activities.
· Public safety radios are expensive compared with commercial handsets--they cost
about $3,000--reflecting their specialized nature and the comparatively small market. If the costs
of these radios are to be significantly reduced, greater economies of scale will be necessary.
· Current attempts to provide enhanced services include establishment of a statewide
network in New York and a partnership in Washington, D.C., with Motorola and Flarion
Technologies that aims to build a broadband data network.
· Using dedicated infrastructure rather than commercial services for public safety
services is costly and is one reason that public safety technology lags the state of the art. Yet
4Glen Nash, State of California Department of General Services; Capt. Thomas Cowper, New
York State Wireless Project; Marilyn Praisner, Montgomery County (Md.) Council; Nancy Jesuale,
NetCity Engineering; Robert LeGrande, Office of the Chief Technology Officer, District of Columbia; and
Thera Bradshaw, City of Los Angeles.
OCR for page 5
SUMMARY OF REMARKS MADE BY FORUM PANELISTS 5
today's commercial systems have not been designed to meet public safety requirements. One
possible remedy is to move to nondedicated spectrum--and possibly nondedicated
infrastructure--while providing public safety users with priority access. Implementation would
require the incorporation of public safety requirements into the design of new systems and the
development of technologies supporting robust authentication of public safety users and priority
access to shared networks. Generally, more research is needed on future directions for public
safety communications.
· Wide-area mobile data applications will require more spectrum than planned new
allocations--4.9 GHz for broadband hotspot and fixed communication and 24 MHz in the 700
MHz band, which may or may not become available in 2006. Use of the 4.9 GHz band is
complicated by FCC rules that currently prohibit use of the 802.11j technology currently being
developed for use in the Japanese market. The Spectrum Coalition for Public Safety advocates
the allocation of an additional 10 MHz in the upper 700 MHz band.
FEDERAL SPECTRUM MANAGEMENT AUTHORITIES
In Session 3, panelists discussed current developments in spectrum policy.5 Panelists
noted that several spectrum reform initiatives were under way:
· Considerable progress has been made recently in several areas. For example, new
allocations have been made for ultrawideband, 5 GHz unlicensed, and 70 GHz, 80 GHz, and 90
GHz services, and new allocations are under consideration for third-generation (3G) wireless
services. Since the implementation of spectrum auctions, more than 25,000 licenses have been
made available and more than $14 billion in revenue has been received by the U.S. Treasury.
More flexible services rules and rules encouraging private spectrum transactions have provided
additional opportunities and incentives for efficient use.
· The administration's spectrum policy initiative, as outlined in the executive
memorandum, will recommend improvements to spectrum management policies and procedures.
One particularly useful outcome anticipated from the presidential initiative would be a concise
summary of what spectrum users, regulators, and Congress should be doing to improve spectrum
policy over the next 5 to 10 years.
· Areas under current FCC consideration include cognitive radios,6 receiver standards,7
interference temperature,8 standards for broadband over power lines,9 and the identification of
5Michael Gallagher, National Telecommunications and Information Administration, Department
of Commerce; John Muleta, Wireless Telecommunications Branch, Federal Communications Commission;
Julius Knapp, Office of Engineering and Technology, Federal Communications Commission; Andrea
Petro, Office of Management and Budget; and David Siddall, Paul, Hastings, Janofsky & Walker LLP.
6Federal Communications Commission. 2003. Notice of Proposed Rule-Making and Order.
Facilitating Opportunities for Flexible, Efficient, and Reliable Spectrum Use Employing Cognitive Radio
Technologies; Authorization and Use of Software Defined Radios. ET Docket No. 03-108, ET Docket No.
00-47 (terminated), FCC 03-322 (rel. December 30). Available online at
.
7Federal Communications Commission. 2003. Notice of Inquiry. Interference Immunity
Performance Specifications for Radio Receivers, Review of the Commission's Rules and Policies Affecting
the Conversion to Digital Television. ET Docket No. 03-65, MM Docket No. 00-39, FCC 03-54 (rel.
March 24). Available online at .
8Federal Communications Commission. 2003. Notice of Inquiry and Notice of Proposed
Rulemaking. Establishment of an Interference Temperature Metric to Quantify and Manage Interference
and to Expand Available Unlicensed Operation in Certain Fixed, Mobile and Satellite Frequency Bands.
OCR for page 6
6 SUMMARY OF A FORUM ON SPECTRUM MANAGEMENT POLICY REFORM
additional spectrum for advanced wireless services. More spectrum for unlicensed use is being
explored in the TV broadcast bands, in bands below 900 MHz, and for the 50-MHz reallocation
from federal government use to a mixed-use basis at 3.65 to 3.7 GHz. NTIA is also developing
recommendations for the mixed-use band.
· Current legislative proposals include the following: (1) establishing a spectrum
reallocation fund that would reimburse federal users that give up spectrum as a way of increasing
overall spectral efficiency and encouraging more effective allocation among public and private
sector users; (2) authorizing the FCC to charge fees on unauctioned spectrum licenses; and
(3) extending the FCC's auction authority, due to expire in 2007.
Panelists also raised a number of questions to be explored further in spectrum
management reform initiatives, including these:
· How many of the 90,000 frequency assignments require thorough review, and which
areas deserve the highest focus?
· What resources are the agencies that have equity in the spectrum applying to achieve
the goals of their mission for a sound spectrum policy?
· Are federal agencies applying sufficient leadership and resources (including
information technology) to address oft-cited spectrum challenges? Are the resources comparable
to those in the private sector and commensurate with the increasing attention being given to
spectrum issues?
· Alternatives to the current public safety business model, which is based on exclusive
use of spectrum and self-provisioning, should be considered. Issues to explore include (1) how to
separate network access from the provisioning and management of the network, (2) how to
increase choice among equipment vendors, and (3) how priority access can be used to provide
public safety communications with commercial systems and infrastructure.
· What enables the FCC and NTIA to work well together? What is the value of meeting
together on a monthly basis?
· How is interference testing done today? What are its motives, methods, and costs?
Would a centralized testing process and facility be useful?
· How does one tell if engineering principles--e.g., interference, harmful interference,
signal-to-noise-ratio, noise floor--are being invoked legitimately--or not?
· To what extent can economic incentives replace traditional spectrum planning? To
what extent will competition and consumer pressure provide incentives for industry to address
interference problems? How much of an incentive does purchasing spectrum rights provide
companies to invest in more efficient technologies rather than seeking new allocations?
FREQUENCY MANAGERS AND AMATEUR RADIO
In Session 4, panelists from the Association of Public-Safety Officials, Comsearch, the
United Telecom Council, and the American Radio Relay League10 discussed issues relating to
ET Docket No. 03-237, FCC 03-289 (rel. November 28). Available online at
.
9Federal Communications Commission. 2004. Notice of Proposed Rule Making. Carrier Current
Systems, Including Broadband Over Power Line Systems, Amendment of Part 15 Regarding New
Requirements and Measurement Guidelines for Access Broadband. ET Docket No. 03-104, ET Docket No.
04-37, FCC 04-29 (rel. February 23). Available online at
.
10Robert Gurss, Association of Public-Safety Officials; Kenneth Ryan, Comsearch; William
Moroney, UTC; and Paul Rinaldo, American Radio Relay League.
OCR for page 7
SUMMARY OF REMARKS MADE BY FORUM PANELISTS 7
frequency management and coordination for public safety, utilities and other critical
infrastructure, commercial applications, and amateur radio.
Panelists made several observations about requirements for public safety and critical
infrastructure uses of spectrum:
· Voice and data services for the control, operation, and maintenance of utility and other
critical infrastructure companies require a very high level of reliability, which has been provided
by dedicated networks and radio systems.
· In life-safety applications, efficiency should not be based simply on a measure of users
per channel, but rather on how spectrum can best be used to support these missions.
With regard to providing broadband services over power lines, panelists offered
contrasting views:
· The utility industry is encouraged about the potential of the technology to offer
broadband over power lines and provide an additional true facilities-based competitor in
broadband services. The industry is actively examining the interference issues that may result
from the service offering, and it is working with groups that could be affected by interference
problems.
· Amateur radio operators are concerned about emissions from broadband over power
lines. The interference concern is heightened because overhead power lines, many in close
proximity to amateur receivers, would act as transmitters. These segments would be resonant at
different frequencies depending on their length (e.g., reflecting pole spacing) and thus cannot be
planned for or filtered out properly. Because of the high potential for interference, discussions at
the FCC have focused on establishing a power limit that would accommodate both uses.
Panelists also offered several suggestions for improving spectrum management policies:
· Amateur radio operators have long made successful use of dynamic frequency
assignment by applying a listen-before-transmit rule and asking if a given channel is occupied
before transmitting.
· Software tools used by commercial frequency coordination and management
organizations, such as geographical information systems and databases, and the best practices of
those organizations could be useful in improving the efficiency and effectiveness of federal
spectrum management.
· Spectrum policy should provide flexibility to enable interoperability and spectrum
sharing between public safety and critical infrastructure users. There is also interest in exploring
the deployment of joint radio systems.
· Access to government databases containing nonrestricted data for frequency
assignments could improve the identification of relevant licensees and users and the coordination
of licenses for commercial services, especially those that are deployed in bands shared with the
government.
· Shared databases and common tools could also eventually allow for real-time
registration and coordination of commercial services, permitting same-day frequency clearance,
deployment, and operation.
OCR for page 8
8 SUMMARY OF A FORUM ON SPECTRUM MANAGEMENT POLICY REFORM
CONSUMER ADVOCACY ORGANIZATIONS
In Session 5, panelists from the Consumer Federation of America and the Media Access
Project11 discussed several issues of concern to consumer advocacy organizations with regard to
spectrum policy and associated issues of media access. The comments provided by the speakers
included these:
· Radio spectrum is a public resource that should be used to promote the widest possible
dissemination of information from diverse and even antagonistic sources. Broadcast licensees are
supposed to serve the public interest.
· As illustrated by the successful campaign to block low-power FM broadcasting,
incumbents tend to act to exclude competing or potentially disruptive technologies and services.
· A balance should be sought between unlicensed spectrum; exclusive licenses by
service, such as the family radio service that can only be used for voice services; and other
exclusive licensing to ensure that each broadcaster serves the public interest in its own broadcast
area..
· The view of spectrum licenses as property rights goes beyond the original premise
behind licensing. The granting of exclusive licenses to provide a service to the public reflected
the view at the time that this was the only way to make broadcasting economically viable.
· The adoption of secondary markets in spectrum is not likely to increase the number of
media voices, as large media firms will be able to outspend new competitors and prevent them
from developing competitive services.
CELLULAR CARRIERS
In session 6A, panelists from two national cellular carriers, Cingular Wireless and
Verizon Wireless, and an industry association, the Cellular Telecommunications & Internet
Association (CTIA),12 discussed the impact of spectrum policy on cellular voice and data
services. Observations made by panelists included these:
· Innovation and investment by cellular carriers have resulted in substantial growth and
increased spectral efficiency. Substantial investments in upgraded infrastructure and increased
capacity have been necessary to meet subscriber demand within existing spectrum allocations.
For example, the number of subscribers has grown by a factor of 12 over the past decade (from
12 million subscribers to over 150 million subscribers), the number of minutes used per
subscriber has grown fourfold, and the speed of commercially available data services has
increased roughly 100-fold (from 4.8 kbps to over 500 kbps). Only a fourfold increase in
spectrum, from 50 MHz to roughly 190 MHz, has been required to achieve these increases (this
does not include spectrum to be assigned for 3G services).
· Adding other users to cellular bands would be costly, create potential risks, and not
yield customer benefits in the form of new applications or services. It is appropriate to consider
ways of exploiting so-called white space, but this is not appropriate for bands where long-term
stability is required for investment and innovation to continue. New concepts introduced by the
11Harold Feld, Media Access Project, and Mark Cooper, Consumer Federation of America.
12Jim Bugel, Cingular Wireless; Jim Smoak, Verizon Wireless; and Diane Cornell, Cellular
Telecommunications & Internet Association.
OCR for page 9
SUMMARY OF REMARKS MADE BY FORUM PANELISTS 9
FCC's Spectrum Policy Task Force, such as spectrum sharing, will require careful economic and
technological analysis to understand the short- and long-term effects of such changes.
· A mix of licensed and unlicensed spectrum uses is appropriate, and cellular carriers
are making use of both today. Exclusive use over a spectrum band for licensed services provides
carriers with incentives to invest in infrastructure and to innovate, and it provides carriers with
needed protection from interference.
· Both government and commercial spectrum use should be subject to a cost-benefit
analysis that includes technical and economic aspects and opportunity costs.
· A useful approach to spectrum management reform would be the establishment of an
independent commission of spectrum experts to review spectrum allocations, analogous to the
reviews of military facilities conducted under the Base Realignment and Closure Act.
· A longer term for the U.S. ambassador to the World Radiocommunication Conference
would allow more attention to be devoted to international harmonization of spectrum allocations.
Although technological advances have made it possible to build handsets that can use multiple
bands, spectrum allocation differences from country to country add costs and ultimately increase
consumer prices.
· Panelists saw opportunities with respect to public safety spectrum use, both to improve
the spectral efficiency of these services and to establish new mechanisms for sharing or trading
public safety spectrum in exchange for priority access to commercial services.
BROADCASTING SERVICES
In Session 6B, panelists from a broadcast industry association, a broadcaster , and a
satellite service provider13 discussed spectrum policy on terrestrial broadcasting and associated
satellite services.
The panelists made the following observations:
· There are long-standing broadcast spectrum sharing arrangements between television
broadcasters and other users such as public safety and radio astronomy.
· Investments in digital transmitters by broadcasters are improving spectral efficiency
by doubling the number of digital television (DTV) stations in the same amount of spectrum.
· Progress is being made on the transmission side, with digital broadcasting operational
at 1,155 digital television stations in 203 television markets, containing 99.4 percent of U.S.
television households. In the receiver side, however, digital television penetration is well below
10 percent of households.
· Digital transmission for the broadcasters is expected to generate additional revenue
from such services as high-definition television, multicasting, and data transmission and other
value-added services.
· Digital repacking efforts aim to move all DTV stations to channels 2 to 51, returning
108 MHz of spectrum to the government. However, repacking has proved challenging in urban
areas and is complicated by the existence of low-power television stations and the congressional
desire for 175 additional DTV licenses.
· Changing the licensing structure by geographic area and increasing co-location, which
would permit greater use of adjacent channels, would promote further efficiency in the broadcast
spectrum and would create economic incentives for completing the transition to DTV.
· Although an estimated 85 percent of U.S. households receive a television signal from
cable or satellite antennas, roughly 80 million television sets, or one-third of all television sets in
13David Donovan, MSTV; Greg Schmidt, LinTV; and Kalpak S. Gude, PanAmSat.
OCR for page 10
10 SUMMARY OF A FORUM ON SPECTRUM MANAGEMENT POLICY REFORM
the United States (e.g., second sets in a kitchen or bedroom) receive only over-the-air terrestrial
television. The cable and satellite industries also rely on over-the-air television programming that
is rebroadcast over those systems.
· Underlay or unlicensed operation in broadcast spectrum should be delayed or
prohibited because (1) use of broadcast spectrum will undergo numerous changes as DTV
stations are repositioned during digital transition; (2) it will take time to characterize the
propagation of new DTV transmissions; (3) receivers, which are provided by the consumer
electronic industry and thus have performance characteristics not under the control of
broadcasters, are subject to interference from unlicensed devices; (4) no feedback mechanism
exists to advise of digital signal degradation; and (5) adding other users to broadcast bands would
undesirably constrain the future evolution of television transmission systems.
· Capacity increases being realized by the transition to digital technology for satellite
transmissions, permitting six regular digital channels or two HDTV channels as compared with
one analog channel per 36 MHz transponder, should not be used to justify the return of spectrum.
Instead, such increases should be viewed as providing an opportunity to offer more channels and
services, which in turn provides an economic incentive for the investment in the analog-to-digital
migration.
· Spectrum policies based on definitions of spectral efficiency that emphasize increasing
the number of spectrum users will harm the internal efficiency efforts of existing spectrum users.
· The higher-order modulation schemes that have been employed in satellite
communications increase both data rates and spectral efficiency but are more susceptible to
interference. Additionally, the smaller earth station antennas currently used by residential users
also render satellite links more susceptible to interference than were earlier generations of
antennas.
COMMERCIAL AND GOVERNMENT SERVICES AND APPLICATIONS
In Session 6C, panelists from General Dynamics Decision Systems, Boeing, Lockheed
Martin, and Iridium14 discussed commercial and government services and applications. Panelists
offered a number of observations about the evolution of wireless technology:
· Even as new technologies and spectrum management policies come into being, legacy
devices and associated management policies will still have to be accommodated for some time.
· New adaptive, smart radio technologies--software-defined radios, smart antennas, and
intelligent signal processing--can significantly increase the processing gain in the spatial domain
but the extent to which they do this will depend on a number of factors, including the band in
which they operate, the spectrum environment (propagation environmental condition), cost,
application, and platform.
· Many licensed spectrum applications, such as public safety, defense, and some
internal corporate business networks, are not market-based, and procuring them from the market
would be difficult, as commercial operators would not want to be liable for safety of life and
internal business uses that require accuracy 24 hours per day, 7 days per week.
Panelists also offered several observations about current and future policy-making
processes:
14 Bruce Fette, General Dynamics Decision Systems; Thomas Walsh, Boeing; Jennifer Warren,
Lockheed Martin; and Pat Mahoney, Iridium.
OCR for page 11
SUMMARY OF REMARKS MADE BY FORUM PANELISTS 11
· The current relationship between NTIA and the FCC, which is based in large part on
personality and individual working relationships, may not be adequate, especially as increased
sharing between federal and nonfederal spectrum users raises jurisdictional questions and
otherwise complicates decision making. These complications exist today: For instance, who
resolves disputes involving commercial services that have out-of-band impact on government-
exclusive bands?
· Increased information on coordination between the Interdepartment Radio Advisory
Committee (IRAC) and FCC would be helpful. A public tracking system to monitor the
application request process--for example, when the IRAC sends questions to the FCC about an
application--would increase confidence that all necessary information has been received,
decrease errors, and reduce the time staff spend responding to questions.
· The international dimensions of spectrum decisions, which are not emphasized in the
executive memorandum, deserve more attention. For example, domestic decisions can have a
significant impact on U.S. licensees that also operate in other countries and have to obtain
spectrum assignments or other regulatory approval there as well.
· There is a need to increase U.S. representation in bilateral and international
negotiations, which have broad implications for how U.S. allocations and operations are carried
out.
TECHNOLOGY, STANDARDS, AND COMMERCIAL R&D
Panelists in Session 7 discussed various ways in which standards setting and technology
development relate to spectrum policy.15 Several speakers addressed the issue of standards,
noting that
· Standards-based systems have experienced significant growth in both market size and
applications over the past few years, despite the recent downturn in the telecommunications
industry. The most notable example is wireless local area networking based on IEEE 802.11
standards.
· Standards do not freeze technology development in time. Standards are constantly
evolving as a result of competition among vendors to introduce new and improved technologies
and features. Such evolution drives the standards development organizations to continually
improve standards to meet the market demand while also maintaining some degree of backward
compatibility for current users.
· Although the standards process works well for establishing interoperability between
devices built to a common standard, it does not address interoperability or coexistence with other
systems very well. There is a potential role for regulators here--namely, the establishment of
rules covering the coexistence of different standards. These rules should be flexible enough to
permit continued technology evolution.
On the subject of licensed and unlicensed spectrum, speakers made several points,
including the following:
· Licensed and unlicensed approaches to managing spectrum play useful roles for
different technologies and applications, and both support increasing spectral efficiency.
15 Carl R. Stevenson, Agere Systems; Charles Wheatley, Qualcomm; Gee Rittenhouse, Lucent
Laboratories; Kevin Kahn, Intel Corporation; and Carl M. Panasik, Texas Instruments Inc.
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12 SUMMARY OF A FORUM ON SPECTRUM MANAGEMENT POLICY REFORM
· For public safety or homeland security applications, which have demanding
requirements, licensed spectrum would offer advantages over unlicensed spectrum because access
charges for services have driven efficiency, its reliability is proven, and it leverages world
competition to reduce costs. These applications could make use of commercial services if
provisions are made for priority access and if liability concerns are addressed.
· Unconstrained interference among different users is possible in unlicensed spectrum,
rendering some applications too unreliable. On the other hand, unlicensed spectrum allows new
technologies to enter the market quickly and offers new opportunities to provide services, such as
wide area networks (WANs).
· Protection for incumbent licensees will remain important.
· Carrier flexibility with respect to the technologies used in their assigned bands is an
important enabler of innovation.
· Additional spectrum for unlicensed devices would enable further innovation and use.
· Innovative technology approaches to identify unused spectrum, such as the
interference temperature, might not be applicable across all spectrum bands but could serve to
identify available spectrum in particular bands with well-defined incumbents.
Views were mixed about the need to increase interference protection for certain
unlicensed devices. Some panelists felt the increasing maturity and economic importance of
some unlicensed uses may be reason enough to create additional protection for certain devices
within unlicensed bands. Others were skeptical about imposing ruled-based enforcement
mechanisms on unlicensed devices because new rules could impede innovation and because there
are a variety of technical options that could be used to resolve interference problems.
Several international policy issues were addressed by the panelists:
· Encouraging technology neutrality in international allocations would permit operators
providing a service, rather than regulators, to determine the best technology architecture to
deliver the services and would permit competition on such dimensions as serving more users per
megahertz, better quality of service, higher data rates, and the introduction of new services.
· Establishing common worldwide bands for cellular mobile communications would
have substantial benefits. Handset designers have found ways of accommodating diverse
spectrum allocations, but this has made handsets more complicated than they need to be and has
added to their cost. Harmonization would create greater economies of scale for manufacturers,
make it more convenient for consumers to use the same device while traveling (especially
laptops), and reduce conflicts with regional regulations when portable devices are taken to other
countries.
WI-FI AND BROADBAND WIRELESS ACCESS TECHNOLOGIES
In Session 8, panelists from several firms involved in wireless LAN and broadband
technologies16 discussed the implications of these technologies for spectrum management policy.
Comments made by panelists included these:
16Michael Green, Atheros Communications; Leigh Chinitz, Chief Technical Advisor, Proxim;
Siavash Alamouti, Vivato; Duane Buddrius, Alvarion; Bradley Holmes, Arraycomm, Inc.; and Dewayne
Hendricks, the Dandin Group.
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SUMMARY OF REMARKS MADE BY FORUM PANELISTS 13
· Assumptions about spectrum capacity that underlie spectrum management decisions
should be carefully examined. Is spectrum really a finite, limited resource (as common wisdom
would have it), or is capacity actually infinite, with access constrained by time, geographic
location, and frequency?
· The benefits of unlicensed spectrum include the accelerated pace of innovation in
wireless communications and the ripple effects of these technologies on other segments of the
computing and communications market.
· Measures that would advance unlicensed applications include the allocation of
additional spectrum; reuse or shared use of currently underutilized bands; globally harmonized
allocations and harmonized technical rules for operation and compliance testing; the use of
advanced radio technologies; and a simplified product certification process.
· Wireless broadband could serve as an alternative means of delivering broadband to the
40 percent of households and other underserved groups that are not served by either cable or
digital subscriber line (DSL). Roughly 90 percent of these underserved customers are located in
rural areas. The following measures would help expand broadband coverage: (1) permit
increased transmitter power in unlicensed bands for wireless broadband and (2) identify
additional unlicensed spectrum or opportunities for spectrum underlay for wireless broadband.
· Policies should reward more efficient, flexible, and intelligent technologies that permit
incremental moves toward a more open, shared approach to spectrum management and allocation.
It would, however, be counterproductive to force spectrum users to become more spectrally
efficient only to reassign to others the spectrum that was opened up.
· Techniques for spectrum sharing with priority access provide an opportunity to
support and enhance national security and public safety applications without requiring separate
allocations.
· Smart antenna technologies offer a number of advantages over conventional antennas,
including less interference, an increase in bandwidth efficiency and wireless system coverage,
and a reduction in the number of standard radios and thus the total energy transmitted. Full
exploitation of the technology would be advanced if policy would (1) take account of the antenna
gains achieved by smart antennas rather than applying power limits designed for standard
antennas systems and (2) emphasize the efficiency of wireless systems rather than individual
radios.
GOVERNMENT AND ACADEMIC RESEARCH AND DEVELOPMENT
In Session 9, researchers and research managers from Rutgers, the Massachusetts
Institute of Technology, and the Defense Advanced Research Projects Agency (DARPA)17
discussed several active areas of wireless research and some policy implications.
· Inflexible spectrum policies, which can lead to spot shortages, are the driver for
research on dynamic spectrum allocation techniques.
· DARPA's XG program is developing technology to support radios that can
dynamically adapt to the spectral and policy environment. One core program component is
dynamic spectrum selection based on propagation characteristics, measured spectrum use, and
inferred potential interference. The other core component is a policy language to describe rules
for spectrum use that allow the regulations in any particular operating environment to be
17Preston Marshall, Advanced Technology Office, DARPA; Dipankar Raychaudhuri, Rutgers
University; and Moe Win, Massachusetts Institute of Technology.
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14 SUMMARY OF A FORUM ON SPECTRUM MANAGEMENT POLICY REFORM
systematically described and followed by a radio. Results from the XG program will be placed
in the public domain with the expectation that the commercial sector will further develop and
commercialize the technologies and thus make radios more cost-effective.
· Two areas of research into dynamic frequency allocation are agile radios and cross-
layer coordination among radios.
· Agile or cognitive radios are able to select frequencies dynamically across a wide
bandwidth and to generate a variety of waveforms.
· Higher layer spectrum coordination protocols, which provide mechanisms for radio
devices to observe each other, are a possible enabler for spectrum sharing scenarios such as
spectrum underlay or dense unlicensed band deployment. Because interference is a receiver
property, spectrum protocols may be needed to overcome the inherent "hidden node" problem, in
which two transmitters (no matter how agile) cannot hear each other but still interfere at a
receiver that is located between them. Two approaches are being developed to solve this
problem. One is a spectrum policy service that uses an Internet connection to provide a network
layer service that identifies what is operating within a given locality. Another approach, a
spectrum etiquette protocol, would use a common wireless signaling channel rather than an
Internet connection. An 802.11-based protocol has already been developed to provide this
service. Experiments to reduce interference between Bluetooth and 802.11 transmissions suggest
that significant improvements can be made in throughput and quality of service. Either approach
would depend on the development of standardized protocols and could leverage the DARPA XG
program's work on codifying policy.
· Large-scale trials of alternative cognitive radio and spectrum coordination protocol
approaches would help establish the viability of these approaches and provide estimates of the
spectral efficiency they could achieve.
· Ultrawideband (UWB) has had a long history with different meanings and definitions.
UWB's first use was in the spark gap radios pioneered by Marconi. UWB has come back into
play with a recent FCC ruling permitting its use. Today's UWB technology uses very narrow,
short pulses for uses such as short-range, high-speed data for broadband access networks. Based
on the FCC definition, numerous opportunities exist for the deployment of UWB systems,
especially with the wide range of unlicensed spectrum allocation, from 3.1 to 10 GHz. There are
no backward compatibility issues because its use has not been permitted until recently.
· FCC rules permit UWB to be used for many applications but interestingly prohibit its
use for toys. One current area of interest for UWB is short-range communications within the
home.
· Today, UWB is permitted in only one country, the United States, so UWB
applications under development will eventually be constrained by allocation decisions and rules
established by regulators around the world.
Representative terms from entire chapter:
spectrum management
