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Suggested Citation:"Front Matter." National Research Council. 2010. Spectrum Management for Science in the 21st Century. Washington, DC: The National Academies Press. doi: 10.17226/12800.
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SPECTRUM MANAGEMENT FOR SCIENCE IN THE 21ST CENTURY

Committee on Scientific Use of the Radio Spectrum

Committee on Radio Frequencies

Board on Physics and Astronomy

Division on Engineering and Physical Sciences

NATIONAL RESEARCH COUNCIL OF THE NATIONAL ACADEMIES

THE NATIONAL ACADEMIES PRESS

Washington, D.C.
www.nap.edu

Suggested Citation:"Front Matter." National Research Council. 2010. Spectrum Management for Science in the 21st Century. Washington, DC: The National Academies Press. doi: 10.17226/12800.
×

THE NATIONAL ACADEMIES PRESS

500 Fifth Street, N.W. Washington, DC 20001

NOTICE: The project that is the subject of this report was approved by the Governing Board of the National Research Council, whose members are drawn from the councils of the National Academy of Sciences, the National Academy of Engineering, and the Institute of Medicine. The members of the committee responsible for the report were chosen for their special competences and with regard for appropriate balance.

This study was supported by the National Science Foundation under Grant No. 0410006, by the National Aeronautics and Space Administration under Award No. NNH05CC15C, and by the Department of Commerce under Award No. DG133R04CQ0009, TO #26. Any opinions, findings, conclusions, or recommendations expressed in this publication are those of the author(s) and do not necessarily reflect the views of the organizations or agencies that provided support for the project.

International Standard Book Number-13: 978-0-309-14686-9

International Standard Book Number-10: 0-309-14686-0

Copies of this report are available from the

National Academies Press,

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Copyright 2010 by the National Academy of Sciences. All rights reserved.

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Suggested Citation:"Front Matter." National Research Council. 2010. Spectrum Management for Science in the 21st Century. Washington, DC: The National Academies Press. doi: 10.17226/12800.
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THE NATIONAL ACADEMIES

Advisers to the Nation on Science, Engineering, and Medicine


The National Academy of Sciences is a private, nonprofit, self-perpetuating society of distinguished scholars engaged in scientific and engineering research, dedicated to the furtherance of science and technology and to their use for the general welfare. Upon the authority of the charter granted to it by the Congress in 1863, the Academy has a mandate that requires it to advise the federal government on scientific and technical matters. Dr. Ralph J. Cicerone is president of the National Academy of Sciences.


The National Academy of Engineering was established in 1964, under the charter of the National Academy of Sciences, as a parallel organization of outstanding engineers. It is autonomous in its administration and in the selection of its members, sharing with the National Academy of Sciences the responsibility for advising the federal government. The National Academy of Engineering also sponsors engineering programs aimed at meeting national needs, encourages education and research, and recognizes the superior achievements of engineers. Dr. Charles M. Vest is president of the National Academy of Engineering.


The Institute of Medicine was established in 1970 by the National Academy of Sciences to secure the services of eminent members of appropriate professions in the examination of policy matters pertaining to the health of the public. The Institute acts under the responsibility given to the National Academy of Sciences by its congressional charter to be an adviser to the federal government and, upon its own initiative, to identify issues of medical care, research, and education. Dr. Harvey V. Fineberg is president of the Institute of Medicine.


The National Research Council was organized by the National Academy of Sciences in 1916 to associate the broad community of science and technology with the Academy’s purposes of furthering knowledge and advising the federal government. Functioning in accordance with general policies determined by the Academy, the Council has become the principal operating agency of both the National Academy of Sciences and the National Academy of Engineering in providing services to the government, the public, and the scientific and engineering communities. The Council is administered jointly by both Academies and the Institute of Medicine. Dr. Ralph J. Cicerone and Dr. Charles M. Vest are chair and vice chair, respectively, of the National Research Council.


www.national-academies.org

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COMMITTEE ON SCIENTIFIC USE OF THE RADIO SPECTRUM

MARSHALL H. COHEN,

California Institute of Technology,

Co-Chair

ALBIN J. GASIEWSKI,

University of Colorado at Boulder,

Co-Chair

DONALD C. BACKER,

University of California, Berkeley

ROBERTA BALSTAD,

Columbia University

STEVEN W. ELLINGSON,

Virginia Polytechnic Institute and State University

DARREL EMERSON,

National Radio Astronomy Observatory

AARON S. EVANS,

University of Virginia and National Radio Astronomy Observatory

JOEL T. JOHNSON,

Ohio State University

PAUL KOLODZY,

Kolodzy Consulting, LLC

DAVID B. KUNKEE,

The Aerospace Corporation

MOLLY K. MACAULEY,

Resources for the Future, Inc.

JAMES M. MORAN,

Harvard-Smithsonian Center for Astrophysics

LEE G. MUNDY,

University of Maryland at College Park

TIMOTHY J. PEARSON,

California Institute of Technology

CHRISTOPHER S. RUF,

University of Michigan

FREDERICK S. SOLHEIM,

Radiometrics Corporation

DAVID H. STAELIN,

Massachusetts Institute of Technology

ALAN B. TANNER,

Jet Propulsion Laboratory

Staff

DONALD C. SHAPERO, Director,

Board on Physics and Astronomy

BRIAN D. DEWHURST, Program Officer (through July 2009)

DAVID LANG, Program Officer

MERCEDES ILAGAN, Administrative Assistant (through February 2008)

CARYN KNUTSEN, Program Associate (from March 2008)

VAN AN, Financial Associate (through May 2008)

BETH DOLAN, Financial Associate (from June 2008)

Suggested Citation:"Front Matter." National Research Council. 2010. Spectrum Management for Science in the 21st Century. Washington, DC: The National Academies Press. doi: 10.17226/12800.
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COMMITTEE ON RADIO FREQUENCIES

PAUL A. VANDEN BOUT,

National Radio Astronomy Observatory,

Chair

JEFFREY PIEPMEIER,

NASA Goddard Space Flight Center,

Vice-Chair

ANA P. BARROS,

Duke University

DOUGLAS C.-J. BOCK,

University of California, Berkeley/Combined Array for Research in Millimeter-wave Astronomy

STEVEN W. ELLINGSON,

Virginia Polytechnic Institute and State University

DAVID G. LONG,

Brigham Young University

DARREN McKAGUE,

University of Michigan

JAMES M. MORAN,

Harvard-Smithsonian Center for Astrophysics

MELINDA PIKET-MAY,

University of Colorado at Boulder

STEVEN C. REISING,

Colorado State University

ALAN E.E. ROGERS,

Massachusetts Institute of Technology/Haystack Observatory

LUCY ZIURYS,

University of Arizona

Staff

DONALD C. SHAPERO, Director,

Board on Physics and Astronomy

DAVID B. LANG, Program Officer

CARYN J. KNUTSEN, Research Associate

Suggested Citation:"Front Matter." National Research Council. 2010. Spectrum Management for Science in the 21st Century. Washington, DC: The National Academies Press. doi: 10.17226/12800.
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BOARD ON PHYSICS AND ASTRONOMY

MARC A. KASTNER,

Massachusetts Institute of Technology,

Chair

ADAM S. BURROWS,

Princeton University,

Vice-Chair

PHILIP H. BUCKSBAUM,

Stanford University

PATRICK L. COLESTOCK,

Los Alamos National Laboratory

JAMES DRAKE,

University of Maryland

JAMES EISENSTEIN,

California Institute of Technology

ANDREA M. GHEZ,

University of California, Los Angeles

PETER F. GREEN,

University of Michigan

LAURA H. GREENE,

University of Illinois at Urbana-Champaign

MARTHA P. HAYNES,

Cornell University

JOSEPH HEZIR,

EOP Group, Inc.

MARK B. KETCHEN,

IBM Thomas J. Watson Research Center

JOSEPH LYKKEN,

Fermi National Accelerator Laboratory

PIERRE MEYSTRE,

University of Arizona

HOMER A. NEAL,

University of Michigan

MONICA OLVERA DE LA CRUZ,

Northwestern University

JOSE N. ONUCHIC,

University of California, San Diego

LISA J. RANDALL,

Harvard University

CHARLES V. SHANK,

Janelia Farm, HHMI

MICHAEL S. TURNER,

University of Chicago

MICHAEL C.F. WIESCHER,

University of Notre Dame

Staff

DONALD C. SHAPERO, Director

MICHAEL MOLONEY, Associate Director

ROBERT L. RIEMER, Senior Program Officer

JAMES LANCASTER, Program Officer

DAVID B. LANG, Program Officer

TERI THOROWGOOD, Administrative Coordinator

CARYN J. KNUTSEN, Research Associate

BETH DOLAN, Financial Associate

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Preface

In the early years of the 21st century, policy officials recognized both the need for additional blocks of frequencies in the electromagnetic spectrum for new technologies and the desires of existing users to obtain additional bandwidth. A number of activities were thus begun, with the goals of identifying unused frequencies and suggesting methods by which the regulatory structure could encourage their more efficient use. In June 2002, the Federal Communications Commission (FCC) formed the Spectrum Policy Task Force for the following purposes:

  1. To provide specific recommendations to the FCC for ways in which to evolve the current “command-and-control” approach to spectrum policy into a more integrated, market-oriented approach that provides greater regulatory certainty while minimizing regulatory intervention; and

  2. To assist the FCC in addressing ubiquitous spectrum issues, including interference protection, spectral efficiency, effective public-safety communications, and implications of international spectrum policies.

The Spectrum Policy Task Force concluded that “while the commission has recently made some major strides in how spectrum is allocated and assigned in some bands, principally through flexible rules and competitive bidding, spectrum policy is not keeping pace with the relentless spectrum demands of the market. The task force has begun the process of reexamining 90 years of spectrum policy to

Suggested Citation:"Front Matter." National Research Council. 2010. Spectrum Management for Science in the 21st Century. Washington, DC: The National Academies Press. doi: 10.17226/12800.
×

ensure that the commission’s policies evolve with the consumer-driven evolution of new wireless technologies, devices, and services.”1

Recognizing the growing importance of radio observations to their respective missions and the increasing potential for interference from new wireless technologies, NASA, the Department of Commerce, and the National Science Foundation commissioned the National Research Council (NRC) to identify the spectrum needs of today’s scientific activities and to assist spectrum managers in balancing the requirements of scientific uses of the spectrum with those of other interests. This report is written in response to that request. The committee discussed its original charge at length and chose to consider only the passive (“receive-only”) scientific applications of the radio spectrum, and specifically how the requirements for spectrum could be expected to evolve over the next two decades.2 This decision did not imply any prioritization of the active versus passive scientific uses of the spectrum, but instead stemmed from the committee’s recognition that passive scientific uses involve unique issues and that the committee had a limited amount of time in which to complete its task.

To address its task, the NRC’s Committee on Scientific Use of the Radio Spectrum—comprising representatives of universities, private industry, and nonprofit organizations3—employed four in-person meetings, four town hall meetings, and numerous teleconferences in the development of its report. The committee’s work was aided by presentations from a number of outside experts who provided detailed information at in-person meetings.

The committee focused on three major topics: Earth remote sensing (see Chapter 2), radio astronomy (see Chapter 3), and interference mitigation (see Chapter 4). It conducted an in-depth study of each of the major topics, including the current and expected future status of Earth remote sensing and radio astronomy and applicable radio frequency interference mitigation technologies. The committee developed a series of findings on the basis of the material presented in these chapters, together with an associated series of recommendations, to help ensure the viability of these scientific endeavors. The findings and recommendations are detailed in Chapter 5. As dictated by the statement of task, the committee did not make recommendations on the allocation of specific frequencies, but it did comment on spectrum use by the relevant scientific communities and how it might be protected in the future.

This report attempts to lay the foundation of an effort to identify the spectrum needs of radio astronomy and Earth remote sensing, identify the benefits of these two activities, and develop practical, forward-looking approaches to spectrum

1

Federal Communications Commission, Report of the Spectrum Policy Task Force, Washington, D.C., November 2002.

2

The committee’s statement of task appears in Appendix A.

3

Biosketches of the members of the committee are provided in Appendix B.

Suggested Citation:"Front Matter." National Research Council. 2010. Spectrum Management for Science in the 21st Century. Washington, DC: The National Academies Press. doi: 10.17226/12800.
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access that are needed to ensure the necessary conditions for their important observations.

It is noted that a report on the uses of passive service4 bands for both Earth remote sensing and radio astronomy by a panel of the NRC’s Committee on Radio Frequencies (CORF) was published in 2007.5 The present report differs from the 2007 report in assessing both the current and future uses of the passive services. This report also includes a focus on technology for interference mitigation.

4

The passive services are those for which the signal is produced by nature and the applications are “receive-only.”

5

National Research Council, Handbook of Frequency Allocations and Spectrum Protection for Scientific Uses, Washington, D.C.: The National Academies Press, 2007.

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Acknowledgment of Reviewers

This report has been reviewed in draft form by individuals chosen for their diverse perspectives and technical expertise, in accordance with procedures approved by the National Research Council’s (NRC’s) Report Review Committee. The purpose of this independent review is to provide candid and critical comments that will assist the institution in making its published report as sound as possible and to ensure that the report meets institutional standards for objectivity, evidence, and responsiveness to the study charge. The review comments and draft manuscript remain confidential to protect the integrity of the deliberative process. We wish to thank the following individuals for their review of this report:

Paul Feldman, Fletcher, Heald & Hildreth, PLC,

Dale N. Hatfield, Independent Consultant, Longmont, Colorado

Anthony Janetos, Pacific Northwest National Laboratory,

Roger Lang, George Washington University,

Michael Marcus, Marcus Spectrum Solutions,

Thomas Meissner, Remote Sensing Systems, Inc.,

Steven Reising, Colorado State University,

Chris Salter, National Astronomy and Ionosphere Center, Cornell University,

Paul Vanden Bout, National Radio Astronomy Observatory,

William “Jack” Welch, University of California, Berkeley, and

David Woody, California Institute of Technology, Owens Valley Radio Observatory.

Suggested Citation:"Front Matter." National Research Council. 2010. Spectrum Management for Science in the 21st Century. Washington, DC: The National Academies Press. doi: 10.17226/12800.
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Although the reviewers listed above have provided many constructive comments and suggestions, they were not asked to endorse the conclusions or recommendations, nor did they see the final draft of the report before its release. The review of this report was overseen by Martha Haynes, Cornell University. Appointed by the NRC, she was responsible for making certain that an independent examination of this report was carried out in accordance with institutional procedures and that all review comments were carefully considered. Responsibility for the final content of this report rests entirely with the authoring committee and the institution.

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 2.2  Brightness Temperatures, Geophysical Measurements, and Missions,

 

48

   

 Fundamentals of Microwave Radiometry for EESS Applications,

 

48

   

 Measurement of Specific Geophysical Parameters,

 

52

   

 2.3  Current and Future Space Missions, Activities, and Spectrum Usage,

 

53

   

 2.4  Current and Future Non-Space-Based Activities and Spectrum Usage,

 

59

   

 2.5  The Impact of Radio Frequency Interference on Earth Exploration-Satellite Service Observations,

 

61

   

 Introduction to the Problem of Radio Frequency Interference: Immediate Impacts on EESS,

 

61

   

 Evidence of Impact of Radio Frequency Interference on EESS Observations,

 

63

   

 Potential Future Radio Frequency Interference and Its Impact on EESS Observations,

 

80

   

 2.6  Summary of the Importance of and Risks to Continued Contributions of the Earth Exploration-Satellite Service in the Future,

 

86

3

 

THE RADIO ASTRONOMY SERVICE

 

88

   

 3.1  The Scientific Impact of Radio Astronomy,

 

90

   

 Origin of Planets and the Solar System,

 

90

   

 Origin and Evolution of the Universe,

 

92

   

 Pulsars and General Relativity,

 

95

   

 Galactic Nuclei and Black Holes,

 

96

   

 Galaxies,

 

101

   

 Solar Physics and Space Weather,

 

102

   

 Serendipity and the Transient Universe,

 

104

   

 Summary,

 

105

   

 3.2  Radio Observatories and Radio Telescopes,

 

106

   

 3.3  Spectrum Requirements and Use,

 

113

   

 Continuum and Line Observations,

 

113

   

 Atmospheric Windows and Absorption Features,

 

115

   

 Current Radio Astronomy Service Allocations,

 

115

   

 Spectrum Use,

 

115

   

 3.4  Sensitivity Requirements,

 

120

   

 Sensitivity Limits,

 

122

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 3.5  Interference and Its Mitigation,

 

123

   

 Examples of Interference in a Protected Band,

 

125

   

 Mitigation,

 

127

   

 3.6  Importance of Radio Astronomy to the Nation,

 

130

   

 Radio Interferometry,

 

130

   

 Communications Disruptions,

 

131

   

 Fundamental Physics,

 

132

   

 Technology Development,

 

132

   

 Precision Antennas,

 

132

   

 Distributed Network Computing,

 

133

   

 Education and Public Outreach,

 

133

4

 

TECHNOLOGY AND OPPORTUNITIES FOR THE MITIGATION OF RADIO FREQUENCY INTERFERENCE

 

135

   

 4.1  Trends in Active Spectrum Usage,

 

136

   

 Current Allocations,

 

136

   

 Current Utilization Studies,

 

138

   

 4.2  Major Drivers of Spectrum Use,

 

145

   

 Assessment of Trends in Spectrum Use for 2008–2015,

 

145

   

 Third-Generation and Fourth-Generation Systems,

 

148

   

 Unlicensed Uses of the Radio Frequency Spectrum,

 

149

   

 Regulatory Changes That Impact Use,

 

151

   

 Technology Changes That Impact Use,

 

153

   

 Summary,

 

155

   

 4.3  Unilateral Mitigation Techniques,

 

156

   

 Technologies for Unilateral Mitigation,

 

157

   

 4.4  Mitigation Through Cooperative Spectrum Usage,

 

168

   

 4.5  Mitigation Costs, Limitations, and Benefits,

 

172

   

 Earth Exploration-Satellite Service (EESS),

 

173

   

 Radio Astronomy Service (RAS),

 

173

   

 Nature of the Costs of Radio Frequency Interference to the EESS and the RAS,

 

174

   

 Summary,

 

176

5

 

FINDINGS AND RECOMMENDATIONS

 

177

   

 5.1  Societal Value of the Passive Services,

 

178

   

 5.2  Characteristics of the Passive Spectrum Services,

 

180

   

 5.3  Threats to the EESS and the RAS from Unintentional Radio Frequency Interference,

 

182

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Radio observations of the cosmos are gathered by geoscientists using complex earth-orbiting satellites and ground-based equipment, and by radio astronomers using large ground-based radio telescopes. Signals from natural radio emissions are extremely weak, and the equipment used to measure them is becoming ever-more sophisticated and sensitive.

The radio spectrum is also being used by radiating, or "active," services, ranging from aircraft radars to rapidly expanding consumer services such as cellular telephones and wireless internet. These valuable active services transmit radio waves and thereby potentially interfere with the receive-only, or "passive," scientific services. Transmitters for the active services create an artificial "electronic fog" which can cause confusion, and, in severe cases, totally blinds the passive receivers.

Both the active and the passive services are increasing their use of the spectrum, and so the potential for interference, already strong, is also increasing. This book addresses the tension between the active services' demand for greater spectrum use and the passive users' need for quiet spectrum. The included recommendations provide a pathway for putting in place the regulatory mechanisms and associated supporting research activities necessary to meet the demands of both users.

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