**Before the**

**Federal Communications Commission**

**Washington, D.C. 20554**

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| In the Matter of                 | * | ET Docket No. 03-108           |
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**NOTICE OF PROPOSED RULE MAKING AND ORDER**

**Adopted: December 17, 2003 Released: December 30, 2003**

**Comment date:** **\[75 days from publication in Federal Register\]**

**Reply comment date:** **\[105 days from publication in Federal
Register\]**

By the Commission: Chairman Powell, Commissioners Copps, Martin and
Adelstein issuing separate statements.

Table of Contents [Para. No.]{.underline}

[**I.** **Introduction and executive summary**
1](#introduction-and-executive-summary)

[**II.** **Background** 8](#background)

[**III.** **Discussion** 18](#discussion)

[**A.** **Cognitive Radio Capabilities**
20](#cognitive-radio-capabilities)

[**B.** **Application: Rural Markets and Unlicensed Devices**
33](#application-rural-markets-and-unlicensed-devices)

[1. Background 33](#background-1)

[2. Discussion 36](#discussion-1)

[**C.** **Application: Secondary Markets**
48](#application-secondary-markets)

[1. General 48](#general)

[2. Interruptible Spectrum Leasing 51](#interruptible-spectrum-leasing)

[**D.** **Other Applications of Cognitive Radio Technology**
68](#other-applications-of-cognitive-radio-technology)

[1. Dynamically Coordinated Spectrum Sharing
68](#dynamically-coordinated-spectrum-sharing)

[2. Facilitating Interoperability between Communication Systems
74](#facilitating-interoperability-between-communication-systems)

[3. Mesh Networks 77](#mesh-networks)

[**E.** **SDR and Cognitive Radio Equipment Authorization Rule Changes**
81](#sdr-and-cognitive-radio-equipment-authorization-rule-changes)

[1. Background 81](#background-3)

[2. Proposals for Part 2 rule changes 85](#__RefHeading___Toc59414248)

[3. Proposals for Part 15 rule changes 95](#__RefHeading___Toc59414249)

[4. Pre-certification testing requirements for cognitive radios
99](#__RefHeading___Toc59414250)

[**IV.** **PROCEDURAL MATTERS** 108](#procedural-matters)

[**V.** **ORDERING CLAUSES** 11](#ordering-clauses)**7**

[**APPENDIX A: PROPOSED RULE CHANGES**](#__RefHeading___Toc59412438)

[APPENDIX B: INITIAL REGULATORY FLEXIBILITY
ANALYSIS](#__RefHeading___Toc59412439)

# Introduction and executive summary

1.  The growth of wireless services over the past several years
    demonstrates the vast and growing demand of American businesses,
    consumers, and government for spectrum-based communication links.
    Spectrum access, efficiency, and reliability have become critical
    public policy issues. Advances in technology are creating the
    potential for radio systems to use spectrum more intensively and
    more efficiently than in the past. Among these advances are
    cognitive radio technologies that can make possible more intensive
    and efficient spectrum use by licensees within their own networks,
    and by spectrum users sharing spectrum access on a negotiated or an
    opportunistic basis.[^1] These technologies include, among other
    things, the ability of devices to determine their location, sense
    spectrum use by neighboring devices, change frequency, adjust output
    power, and even alter transmission parameters and characteristics.
    Cognitive radio technologies open spectrum for use in space, time,
    and frequency dimensions that until now have been unavailable. Such
    technologies are employed today in applications such as wireless
    LANs and mobile wireless service networks, and promise greater
    future benefits.

2.  The ability of cognitive radio technologies to adapt a radio's use
    of spectrum to the real-time conditions of its operating environment
    offers regulators, licensees, and the public the potential for more
    flexible, efficient, and comprehensive use of available spectrum
    while reducing the risk of harmful interference. The important
    potential of these technologies emerges at a crucial time, as the
    Commission addresses increasingly more complex questions of
    improving access to and increasing usage of the finite spectrum
    available, while also seeking to maintain efficiency and reliability
    in spectrum use. The Spectrum Policy Task Force ("SPTF"), in its
    2002 Report, concluded, among other things, that smart radio
    technologies can enable better and more intensive access to spectrum
    and recommended that the Commission strive to remove regulatory
    barriers to their use.[^2]

3.  Cognitive radio technologies can be used to improve spectrum access
    and efficiency of spectrum use under at least four possible
    scenarios. First, a licensee can employ cognitive radio technologies
    internally within its own network to increase the efficiency of use.
    Second, cognitive radio technologies can facilitate secondary
    markets in spectrum use, implemented by voluntary agreements between
    licensees and third parties. For instance, a licensee and third
    party could sign an agreement allowing secondary spectrum uses made
    possible only by deployment of cognitive radio technologies.
    Ultimately cognitive radio devices could be developed that
    "negotiate" with a licensee's system and use spectrum only if
    agreement is reached between a device and the system. Third,
    cognitive radio technologies can facilitate automated frequency
    coordination among licensees of co-primary services. Such
    coordination could be done voluntarily by the licensees under more
    general coordination rules imposed by Commission rules, or the
    Commission could require the use of an automated coordination
    mechanism. Fourth, cognitive radio technologies can be used to
    enable non-voluntary third party access to spectrum, for instance as
    an unlicensed device operating at times or in locations where
    licensed spectrum is not in use.

4.  We undertake this proceeding to explore all the uses of cognitive
    radio technology to facilitate the improved spectrum use made
    possible by the emergence of the powerful real-time processing
    capabilities of cognitive radio technologies. [^3] We also seek
    comment on how our rules and enforcement policies should address
    possible regulatory concerns posed by authorizing spectrum access
    based on a radio frequency (RF) device's ability to reliably gather
    and process real-time information about its RF environment or on the
    ability of device and/or users to cooperatively negotiate for
    spectrum access. We propose and seek comment on rules intended to
    allow a full realization of the potential of these technologies
    under all our regulatory models for spectrum based services.

5.  More specifically, in this *Notice* we first consider in some detail
    the technical capabilities that are or could be incorporated into
    cognitive radio systems and seek comment on possible additional
    capabilities. We then address several specific applications of these
    technologies. These applications cut across the various scenarios
    discussed above. Among the various areas in which cognitive radio
    technologies may provide potential benefits are: permitting the use
    of higher power by unlicensed devices in rural or other areas of
    limited spectrum use, facilitating secondary markets in spectrum,
    enabling possible real-time frequency coordination (such as between
    NGSO satellite and other services), facilitating interoperability
    among different radio systems, and allowing for more extensive
    deployment of mesh networks. We finally consider our equipment
    authorization rules, and whether changes should be made to these
    rules to reflect the growing importance of cognitive radio
    technologies.[^4]

6.  In a number of these areas, we propose specific rule changes to help
    enable devices using cognitive radio technologies. For instance, we
    set out a proposal under which unlicensed devices employing certain
    cognitive radio capabilities would be permitted to transmit at
    higher power levels in rural areas and other areas of limited
    spectrum use. We also include a detailed technical model for
    spectrum leasing based on cognitive radio capabilities that would
    assure a licensee that it would be able to interrupt a lessee's use
    and reclaim spectrum in real time when the need arises. Such a model
    would appear to be most directly applicable to leasing by public
    safety entities if we decide to permit such leasing, but also
    important to other licensees interested in leasing spectrum. We also
    set out proposals: to streamline our rules that require that a copy
    of certain devices' radio software be supplied to the Commission, to
    clarify when devices must be certified under the software defined
    radio rules, and to allow unlicensed devices to automatically select
    their transmit frequency band based upon the country of operation.
    Finally, in light of the initiation of this proceeding, we are
    closing the SDR proceeding of ET Docket No. 00-47.

7.  In sum, we are seeking in this proceeding to facilitate
    opportunities for flexible, efficient, and reliable spectrum use
    employing cognitive radio technologies. We are seeking comment
    generally on how we should modify our rules to enable more effective
    use of cognitive radio technologies, including potential
    applications across a variety of scenarios involving both licensed
    spectrum and unlicensed devices. We are also seeking comment
    specifically on the proposals set out below. By initiating this
    proceeding, we recognize the importance of new cognitive radio
    technologies, which are likely to become more prevalent over the
    next few years and which hold tremendous promise in helping to
    facilitate more effective and efficient access to spectrum. We seek
    to ensure that our rules and policies do not inadvertently hinder
    development and deployment of such technologies, but instead enable
    a full realization of their potential benefits.

# Background

8.  Over the past several years, increasing attention has been paid to
    incorporating new computer processing capabilities into radio system
    technologies. As recognized by the Commission and others in various
    procedural contexts, radio systems are increasingly incorporating
    software into radio system design, and are gaining increased
    abilities to be "cognitive"---to adapt their behavior based on
    external factors.[^5] In addition, this Commission recently opened
    up additional opportunities for taking advantage of the potential of
    cognitive radio technologies in its secondary markets report and
    order.[^6]

9.  Radio manufacturers are incorporating software programming
    capabilities into radios that can make basic functions more easily
    changeable. For more than a decade, most commercial radios have
    contained a microprocessor and software to control operating
    parameters such as frequency and modulation type, although the
    software installed at the factory was not readily changeable after
    manufacture. A software defined radio (SDR) is a device in which the
    operating parameters are controlled by software, allowing the radio
    to be programmed to transmit and receive on a variety of frequencies
    and/or to use one or more different transmission formats supported
    by its hardware design. Manufacturers are now producing radios in
    which the control software can be altered after the radio leaves the
    factory. The ability to change software after manufacture affords
    the user substantial flexibility to operate in a variety of
    frequency bands and/or to use differing modulation systems to access
    available radio services consistent with the Commission's operating
    and service rules.

10. A cognitive radio (CR) is a radio that can change its transmitter
    parameters based on interaction with the environment in which is
    operates. This interaction may involve active negotiation or
    communications with other spectrum users and/or passive sensing and
    decision making within the radio. The majority of cognitive radios
    will probably be SDRs, but neither having software nor being field
    reprogrammable are requirements of a cognitive radio. For instance,
    a cordless phone in the 43.71-44.49 MHz band is a simple form of
    cognitive radio, yet none of the present models have modifiable
    software.[^7]

11. As noted above, radios with cognitive capabilities are already in
    use. Some radios such as wireless LAN devices and CDMA networks
    incorporate cognitive capabilities to allow more efficient spectrum
    use, although there is no requirement in the rules to incorporate
    such capabilities. There are other devices that the Commission's
    rules currently require to have cognitive capabilities. For example,
    to prevent interference to private land mobile radio service
    operations, cordless telephones operating in the 43.71-44.49 MHz
    band are required to incorporate an automatic channel selection
    mechanism that prevents establishment of a communication link on any
    occupied frequency in this band.[^8] Similarly, unlicensed Personal
    Communication Service (PCS) devices are required to monitor the
    spectrum prior to transmission to avoid interference to other
    unlicensed PCS devices.[^9] Further, Unlicensed National Information
    Infrastructure (U-NII) devices operating in the 5.25-5.35 GHz and
    5.47-5.725 GHz bands are required to incorporate dynamic frequency
    selection and transmit power control to avoid interference to
    Federal Government operations.[^10]

12. The Commission has an interest in the development of SDR and
    cognitive radio because these technologies have the potential to
    vastly improve the efficiency of spectrum usage at a time when the
    demand for wireless communications services is rapidly increasing.
    Such radios also have the potential to overcome some of the
    incompatibilities that exist between various communications services
    both domestically and worldwide. The Commission asked its
    Technological Advisory Council (TAC) to assess and report on the
    current state of the art for software defined radios, cognitive
    radios, and similar devices and, to the extent possible, predict
    future developments for these technologies.[^11] The TAC was also
    asked to suggest ways that the availability of such devices might
    affect the Commission's traditional approaches to spectrum
    management and ways the agency could facilitate experimentation and
    commercial deployment of such devices.[^12] Subsequently, the
    Commission adopted a *Notice of Inquiry,* ET Docket No. 00-47 to
    consider whether any changes to the rules were needed to accommodate
    SDR.[^13] Based on the comments received in response to the *Notice
    of Inquiry*, the Commission proposed certain changes to the
    equipment authorization rules for SDRs.[^14] The Commission adopted
    rule changes for SDRs in September 2001 that established a
    definition for SDR and a new procedure for obtaining approval for
    software changes to a radio, and required devices certified as SDRs
    to incorporate a means to prevent unauthorized modifications.[^15]
    In adopting the rule changes, the Commission stated that it would
    consider whether more detailed security requirements were needed for
    SDRs at a later date and left the proceeding open. Because we are
    addressing possible changes to the SDR security and certification
    requirements in this proceeding, we are closing ET Docket No. 00-47
    without adopting any additional rules or changing any rules in that
    proceeding.

13. The SPTF also considered the potential impact of cognitive radios on
    spectrum policy in its November 2002 Report.[^16] It stated that
    while technological advances are contributing to the increased
    diversity of spectrum-based consumer applications, technological
    advances are also providing some potential answers to current
    spectrum policy challenges.[^17] Some recent and significant
    technological advances it noted include the increased use of digital
    technologies and the development of cognitive radio.[^18] The SPTF
    specifically noted that cognitive radios can search the radio
    spectrum, sense the environment and operate in spectrum not used by
    others.[^19] According to the SPTF, by operating in the so called
    white -- or unused -- spaces in the spectrum, cognitive radios can
    therefore enable better and more intensive use of the radio
    spectrum.[^20]

14. On May 19, 2003, the Commission held a workshop to explore state of
    cognitive radio technologies.[^21] The workshop explored the
    application of these new technologies to a variety of spectrum
    management scenarios including, secondary markets, public sector
    spectrum leasing, and new approaches for unlicensed operations in
    new and existing bands.

15. The Commission currently has a pending proceeding that addresses
    cognitive radio technologies in specific applications. The
    Commission adopted a *Notice of Inquiry* in December 2002 seeking
    comment on the possibility of allowing unlicensed operation in
    additional frequency bands, specifically, unused portions of the TV
    broadcast spectrum and the 3650-3700 MHz band.[^22] In that
    proceeding, the Commission recognized that an unlicensed device
    operating in those bands would likely need to incorporate cognitive
    features to share spectrum without causing interference. Such
    features would include the ability to sense spectrum use or know
    where it is located in relation to other transmitters.

16. Federal Government interest in cognitive radio technology has also
    been growing. For example, the Defense Advanced Research Projects
    Agency (DARPA) is administering the neXt Generation (XG)
    Communication program.[^23] This program is developing technology to
    allow, through adaptive techniques, multiple users to share common
    spectrum, yet avoid conflicts in time, frequency, code, and other
    signal characteristics. The goal of the XG program is to enable a
    spectrum usage increase of a factor of ten and achieve easier global
    regulatory compliance. The program is intended to develop technology
    that is applicable to both military and civilian use. DARPA issued
    two requests for comments in the XG program: one concerning the
    program\'s overarching view of adaptive spectrum communications, and
    the other concerning the main features of XG protocols, interfaces,
    behavior sets,[^24] and spectrum access policies.[^25] DARPA states
    that three more requests for comments will be issued in the near
    future that provide more detailed descriptions of the XG features
    outlined in the previously issued request for comments.[^26]

17. In the international arena, other administrations are considering
    the impact of cognitive radio technologies. For example, the agenda
    for the 2007 World Radiocommunication Conference (WRC-07) will
    consider frequency-related matters for the future development of
    International Mobile Telecommunications-2000 (IMT-2000) and systems
    beyond IMT-2000, taking into account the results of ITU-R studies in
    accordance with Resolution 228, as modified at the 2003 World
    Radiocommunication Conference (WRC-03).[^27] In particular, these
    ITU-R studies will be looking at the evolution of IMT-2000 and
    pre-IMT-2000 systems through advances in technology, such as
    adaptive antennas and software defined and cognitive radio
    technology.[^28]

# Discussion

18. Many of today's radio systems contain microprocessors and can, or
    could be programmed to, change their transmission characteristics
    based on their operating environment. The techniques used to do this
    encompass a variety of technologies. For example, some devices can
    automatically select an unoccupied frequency based on detection of
    the frequencies currently in use, or can raise or lower their output
    power to establish a link or to save battery power. Advances in
    technology and, in particular, the ability to rely on software
    changes to modify radio operations as needed, suggest that we should
    not attempt to regulate cognitive radio technology in a way that
    could limit its potential. Instead, it is preferable that we
    understand the types of capabilities that cognitive radio technology
    could provide and how cognitive radio technology could benefit the
    Commission's spectrum management functions. We intend to look
    broadly at these issues, yet we also recognize that technology is
    often designed to address specific objectives. We also recognize
    that cognitive radio technology could raise new interference issues
    that will need to be considered. We expect that cognitive radio
    technology's scope of capabilities and techniques will evolve, and
    all of features need not be present in a given application for the
    radio to be deemed "cognitive." With this broad analytic approach,
    we hope to be in a better position to determine how the use of
    cognitive radio technology could benefit our regulatory processes
    for a given application.

19. In this Notice, we first explore the benefits of cognitive radio
    technology use for spectrum management and regulation and the broad
    capabilities that such technology could encompass. We intend to use
    this framework for further analysis of specific applications of this
    technology. We also seek comment and set forth proposals regarding
    specific applications: rural markets and unlicensed devices, public
    sector spectrum leasing, dynamically coordinated spectrum sharing,
    interoperability between communication systems, and mesh networks.
    We are further proposing changes to our equipment authorization
    processes to accommodate software-defined radios and cognitive radio
    systems.

## Cognitive Radio Capabilities 

20. Cognitive radio technologies have the potential to provide a number
    of benefits that would result in increased access to spectrum and
    also make new and improved communication services available to the
    public. A cognitive radio could negotiate cooperatively with other
    spectrum users to enable more efficient sharing of spectrum. A
    cognitive radio could also identify portions of the spectrum that
    are unused at a specific time or location and transmit in such
    unused "white spaces," resulting in more intense, more efficient use
    of the spectrum while avoiding interference to other users.[^29]
    Cognitive radio technology could also be used to facilitate
    interoperability between or among communication systems in which
    frequency bands and/or transmission formats differ. For example,
    cognitive radio could select the appropriate operating frequency and
    transmission format, or it could act as a "bridge" between two
    systems by receiving signals at one frequency and format and
    retransmitting them at a different frequency and format.[^30]
    Cognitive radio technology can also help advance specific Commission
    policies, such as facilitating the use of secondary markets in
    spectrum and improving access to spectrum in rural areas.[^31]

21. Cognitive radio systems can be deployed in network-centric,
    distributed, ad hoc, and mesh architectures, and serve the needs of
    both licensed and unlicensed applications. For example, cognitive
    radios can function either by employing cognitive capabilities
    within a network base station that in turn controls multiple
    individual handsets or by incorporating capabilities within
    individual devices.

22. There are a number of capabilities that can be incorporated into
    cognitive radios. A first is frequency agility, which is the ability
    of a radio to change its operating frequency, combined with a method
    to dynamically select the appropriate operating frequency based on
    the sensing of signals from other transmitters or on some other
    method. A second is adaptive modulation that can modify transmission
    characteristics and waveforms to exploit opportunities to use
    spectrum.[^32] A third capability is transmit power control, which
    allows transmission at the allowable limits when necessary, but
    reduces the transmitter power to a lower level to allow greater
    sharing of spectrum when higher power operation is not necessary. A
    fourth capability that a cognitive radio could incorporate is the
    ability to determine its location and the location of other
    transmitters, and then select the appropriate operating parameters
    such as the power and frequency allowed at its location. Fifth, a
    cognitive radio could incorporate a mechanism that would enable
    sharing of spectrum under the terms of an agreement between a
    licensee and a third party. Parties may eventually be able to
    negotiate for spectrum use on an ad hoc or real-time basis, without
    the need for prior agreements between all parties. In addition to
    these capabilities, any SDR, including a cognitive radio, could
    incorporate security features to permit only authorized use and
    prevent unauthorized modifications. We seek comment on what other
    features and capabilities a cognitive radio could incorporate.

23. While cognitive radios could incorporate all of the capabilities
    listed above and possibly others, the types of technologies that
    would need to be employed in a particular device would vary based on
    the frequency bands where the equipment is deployed and the types of
    services authorized to operate in those bands. Multiple capabilities
    may in all likelihood be used simultaneously in cognitive
    processing. For example, devices sensing unused spectrum may rely on
    frequency agility in selecting their band of operations and adaptive
    modulation techniques in setting the power, frequency and type of
    signal transmitted. Devices might further manage their signals with
    the location of themselves and other transmitters in mind.
    Negotiations and exchanges with other users might also occur,
    contributing to the increased efficiency and reduction of
    interference for all spectrum users. We review each of these
    capabilities below and seek comment how cognitive radio capabilities
    might function together to achieve spectrum access, efficiency and
    interference mitigation.

24. Dynamic frequency selection (DFS) is defined in the rules as a
    mechanism that dynamically detects signals from other radio
    frequency systems and avoids co-channel operation with those
    systems.[^33] This term was developed in the context of unlicensed
    devices to refer to a technique that uses spectrum sensing and
    frequency selection technology to avoid interference to radar
    systems. We will use this term in the context of cognitive radio to
    more broadly refer to a mechanism that selects an appropriate
    operating frequency for a device based on some specific condition.
    The conditions could include, for example: the location of the
    device, its proximity to other devices, the presence or absence of a
    beacon signal indicating whether use of certain frequencies is
    permitted by a licensee, or an operating requirement to adjust power
    to the minimum needed to establish a reliable communication link.
    Alternatively, a device could change the polarization of its antenna
    to allow two devices to share the same frequency, with one device
    using one polarization and the other using a different polarization.
    The methods that a device could use to decide when to change
    frequency or polarization could include spectrum sensing, geographic
    location monitoring, or an instruction from a network or another
    device. Spectrum sensing may be appropriate in bands for example,
    where services may transmit for long periods of time, *e.g*.,
    broadcast type services, and sensing techniques would not need to be
    repeated frequently to be effective. In other services where
    transmissions occur on an intermittent basis, sensing may be needed
    more often. In the case of unlicensed devices operating in the
    5470-5725 MHz frequency range, the Commission requires continuous
    sensing to prevent interference.

25. There are techniques that can be used to increase the ability of a
    sensing receiver to reliably detect other signals in a band which
    rely on the fact that it is not necessary to decode the information
    in a signal to determine whether a signal is present. For example,
    the use of specialized detectors can improve the ability to sense
    the presence of other signals by 30-40 dB.[^34] Most applications of
    signal detection in commercial practice are based on "radiometric
    detectors" which only function if the signal is greater than the
    noise level in the receiver system. However, in the past decade
    information has become available about an alternative technology
    called cyclostationary detectors or feature detectors which use
    longer sensing times and internal computation to achieve signal
    sensitivities below the noise level for signals of known format. By
    processing a large number of transmitted symbols, without the need
    to demodulate them individually, such a feature detector can achieve
    a processing gain over a radiometric detector which does not use
    knowledge of the signal format. In practice, processing gains of
    30-40 dB can be achieved with computation resources typical of
    today's microprocessors. With such a detector capable of receiving
    signals more than 30 dB below the noise floor the hidden node
    problem[^35] that might result in missing the presence of a signal
    becomes much less likely than with radiometric detectors.

26. Adaptive modulation techniques can modify transmission
    characteristics and waveforms to provide opportunities for improved
    spectrum access and more intensive use of spectrum while "working
    around" other signals that are present. A cognitive radio could
    select the appropriate modulation type for use with a particular
    transmission system to permit interoperability between systems. For
    example, it could switch between different channel access schemes
    such as time division multiple access (TDMA) and code division
    multiple access (CDMA) depending on the type of system in use.[^36]
    Other possible uses of adaptive modulation include dynamically
    selecting the transmission bandwidth based on the availability of
    spectrum and the desired transmission data rate. In addition, new
    types of modulation may be possible in a cognitive radio, such as
    splitting a signal to occupy multiple non-contiguous frequency bands
    simultaneously. For example, using "heteromorphic" waveforms and
    other techniques, open spaces in spectrum can be identified and
    accessed based on a variety of factors.[^37] Heteromorphic waveforms
    can use gaps in spectrum based on time, space, power, frequency,
    bandwidth, data rate, modulation, coding or other characteristics.

27. Transmit power control (TPC) is a feature that enables a device to
    dynamically switch between several transmission power levels in the
    data transmission process. This feature has long been incorporated
    into various communication systems and devices. The term TPC will be
    used broadly to refer to a mechanism that switches the output power
    of a device based upon specific conditions. The conditions could
    include the proximity to other devices, the maximum power permitted
    at a geographic location, or an operating requirement to adjust
    power to the minimum needed to establish a reliable communication
    link.

28. A cognitive radio could incorporate the capability to determine its
    location and the location of other transmitters, and then select the
    appropriate operating parameters such as the power and frequency
    allowed at its location. This could be done by using a geo-location
    technique such as GPS to determine the geographic location, and then
    accessing a database incorporated in a device or by accessing a
    database over a network. In bands such as those used for satellite
    downlinks that are receive-only and do not transmit a signal,
    location technology may be an appropriate method of avoiding
    interference because sensing technology would not be able to
    identify the locations of nearby receivers.

29. A cognitive radio could incorporate a mechanism that would enable
    sharing of spectrum under the terms of an agreement between a
    licensee and a lessee. Because this capability is best explained in
    conjunction with spectrum leasing, it is discussed below in the
    section on secondary markets.

30. While the capabilities described above can enable cognitive radios
    to use spectrum more efficiently, relying on these capabilities in a
    radio raises the possibility of new types of abuse. A GPS receiver
    in a radio could be re-programmed with a geographic offset that
    would make the radio behave as though it were at a location far from
    its actual location. Additionally, databases used to determine the
    location of other transmitters and/or receive sites could be altered
    so a device would not "know" about the presence of other users that
    require protection from interference. Further, software used to
    select the appropriate operating parameters could be altered to make
    a radio transmit at frequencies, power levels or locations where it
    should not. We are seeking comment below on how best to enable
    cognitive radio technologies while taking these issues into account.
    In addition, there are technologies that could possibly be used to
    address some of the device security concerns described above, as
    well as problems in communications security. Both the computer and
    consumer electronics industries have begun to address such problems
    of "trusted computing" and how to secure a device against both
    tampering by third-parties as well as unauthorized modifications by
    its owner. Evolving technologies address problems like third-parties
    eavesdropping on private communications, tampering with messages in
    transit, or misrepresenting a sender's identity (spoofing) in a
    non-secure communication.[^38] In the network computing context,
    technologies are available that can provide a "peer enforcement"
    mechanism; a feature allows a device to identify other users or
    systems operating outside of specific parameters. In the RF radio
    context, our concern has been that a transmitter with unauthorized
    software modifications could violate Commission rules and thereby
    potentially interfere with other services. Manufacturers may be able
    to adapt "peer enforcement" constructs to cognitive radios and these
    new features may minimize the need for direct Commission
    involvement. In addition to a "peer enforcement" mechanism that
    identifies radios operating in violation of the Commission rules,
    new security technologies could allow development of time-limited
    licensing schemes which could ensure that devices are regularly
    updated to maintain compliance with our rules. If, for instance, a
    device were to have to connect to a manufacturer's web site
    periodically in order to retain the right to operate, certain
    assurances could be made about the validity of the device's
    operating parameters and the control software for those parameters.

31. We seek comment on all issues related to the application of
    cognitive radio technology, including the frequency bands and
    services that are most likely to benefit from this technology. We
    conclude that we should continue to prohibit unlicensed devices from
    emitting in designated restricted bands,[^39] which include many
    bands used for Federal Government operations, and seek comment on
    this tentative conclusion.

32. The capabilities that can be employed in cognitive radios could be
    applied in a variety of specific applications and could bring about
    significant changes in how people approach the use of spectrum. As
    we discuss below, some applications could make more efficient use of
    spectrum and others could facilitate the introduction of new uses.
    Some applications could likely be introduced under existing rules,
    whereas other applications may require specific rule changes, as we
    discuss in more detail below.

## Application: Rural Markets and Unlicensed Devices

### Background

33. In its Report, the Spectrum Policy Task Force recommended that the
    Commission explore ways to improve access to spectrum in rural
    areas.[^40] The Commission recently adopted a *Notice of Proposed
    Rule Making* to consider proposals for facilitating access to
    spectrum based services in rural areas.[^41] This *Rural Services
    Notice* addresses licensed spectrum use, and states that the
    Commission will consider unlicensed spectrum use in rural areas in a
    separate proceeding.[^42] We note that the *Rural Services* *Notice*
    seeks comment on a definition of rural areas.[^43]

34. The lower population density and the greater distances between
    people in rural areas can make it difficult for certain types of
    unlicensed operations at the current Part 15 limits to provide
    adequate signal coverage. Such operations include Wireless Internet
    Service Providers (WISPs) and wireless LANs operated between
    buildings or other locations with a large separation between
    transmitters. These operations could potentially benefit from higher
    power limits in rural areas, which would result in greater
    transmission range. Because spectrum is generally not as intensively
    used in rural areas, it may be possible for unlicensed devices to
    operate at higher power levels in those areas without causing
    harmful interference to authorized services. The application of
    cognitive radio technology could help ensure that devices limit
    their higher power operation to only rural areas.

35. Devices such as transmitters used by WISPs and wireless LANs often
    operate under the Part 15 spread spectrum rules in Section
    15.247.[^44] In addition, any type of operation (*e.g*., cordless
    phones, wireless cameras, fleet management devices) is permitted in
    certain bands under Section 15.249.[^45] The power limits currently
    permitted vary depending on the frequency band and in some cases the
    signal characteristics, such as the number of hopping channels for
    spread spectrum devices.

### Discussion

36. Permitting unlicensed devices to operate at higher power levels in
    rural areas could help provide improved access to spectrum in those
    areas by permitting greater transmission range and therefore greater
    coverage areas. Accordingly, we propose to allow higher power
    operation for certain types of unlicensed devices in circumstances,
    as discussed below, that should benefit consumers in rural areas. We
    note that while licensed devices are typically licensed for use in a
    specified geographic area at a specific maximum power level,
    unlicensed devices generally have no geographic restrictions on
    operation and can be used in any location. Because spectrum use in
    rural areas is generally extremely low, measuring spectrum occupancy
    is a method that could potentially be used to determine when a
    device is in a rural area and is eligible to operate at higher
    power. We propose to permit higher power operation by unlicensed
    devices in any area that has limited spectrum use, provided the
    device has capabilities to determine whether it is in an area with
    limited spectrum use. This proposal will benefit persons living in
    rural areas as well as persons living in other areas that may be
    underserved by spectrum based services.

37. We propose to implement these changes by adding a new rule section
    that applies specifically to cognitive radio devices operating in
    the industrial, scientific and medical (ISM) bands on the
    frequencies specified in Sections 15.247 and 15.249 of the rules.
    This proposed rule section would permit higher power operation for
    cognitive devices than these sections currently allow, provided that
    the devices meet all the other requirements of Sections 15.247 and
    15.249, and that the devices incorporate certain features to
    determine that they are in an area with limited spectrum use. We
    also propose to require that unlicensed devices capable of higher
    power operation in areas of limited spectrum use incorporate TPC
    capabilities that, when the device is operating at greater than 1
    Watt, will limit its power output to the minimum level necessary for
    reliable communications. We do not propose any changes to the
    current Sections 15.247 and 15.249 for non-cognitive radio devices.
    The proposed rule for cognitive devices references all the current
    requirements in these sections at this time, which include
    requirements for spread spectrum systems to use specific channel
    spacings, channel bandwidths, power spectral density or number of
    hopping channels.[^46] These requirements were established to
    facilitate spectrum sharing with licensed services and between
    unlicensed operations. However, in areas where spectrum use is low,
    all of the current requirements in the spread spectrum rules to
    facilitate spectrum sharing may not be necessary due to the limited
    number of users in such areas. Because cognitive devices could
    determine when spectrum is in use and avoid transmission on those
    frequencies, it may be possible to relax some of the current
    requirements in the rules in addition to raising the maximum power
    for cognitive devices operated in areas with limited spectrum use
    without causing interference to other users.

38. We propose to allow a transmitter power increase of up to 6 times
    (approximately 8 dB) higher than the current limits in the 902-928
    MHz, 2400-2483.5 MHz and 5725-5850 MHz bands under Section 15.247 of
    the rules, and in the 902-928 MHz, 2400-2483.5 MHz, 5725-5875 MHz
    and 24.0-24.25 GHz bands under Section 15.249 of the rules.[^47]
    This increase is consistent with the Commission's recent proposal in
    ET Docket 03-201 to permit a power increase of 8 dB for spread
    spectrum systems using sectorized antennas.[^48] This proposal would
    increase the signal range by a factor of up to 2.5 and increase the
    coverage area by a factor of six as compared to the current limits,
    which would be particularly beneficial for wireless LAN and WISP
    uses.[^49] Specifically, the proposed maximum transmitter power
    levels or maximum field strength levels in areas with limited
    spectrum use would be:

    a.  Spread Spectrum Devices (§ 15.247)

        -   6 watts for digital transmission systems and the following
            frequency hopping systems: systems in the 2400-2483.5 MHz
            band using at least 75 hopping channels, all systems in the
            5725-5850 MHz band and systems in the 902-928 MHz band using
            at least 50 hopping channels

        -   1.5 watts for frequency hopping systems in the 902-928 MHz
            band using at least 25, but fewer than 50 hopping channels

        -   0.75 watts for frequency hopping systems in the 2400-2483.5
            MHz band using fewer than 75 hopping channels

    b.  Unlicensed operation in the 900 MHz, 2.4 GHz, 5.8 GHz and 24 GHz
        bands (§ 15.249)

        -   125 millivolts per meter at a distance of 3 meters in the
            902-928 MHz, 2400-2483.5 MHz and 5725-5875 MHz bands

        -   625 millivolts per meter at a distance of 3 meters in the
            24.0-24.25 GHz band.

39. We note that all of the bands where higher power operation is
    proposed are allocated on a primary basis for ISM equipment, which
    is generally not susceptible to interference from other
    devices.[^50] However, each of these bands is also used by licensed
    services that are entitled to protection from interference by Part
    15 devices. For example, the 902-928 MHz band is used by the
    Location and Monitoring Service (LMS),[^51] and all of these bands
    are used by Amateur Radio licensees. Because we are proposing to
    both limit higher power operation to areas with limited spectrum use
    and require devices to sense spectrum use before commencing
    transmissions, we believe that implementation of this proposal would
    not significantly increase the interference potential to licensed
    services that operate in one or more of the subject ISM bands. We
    seek comment on this view. We also seek comment on whether any
    particular licensed uses of these bands or portions thereof should
    receive greater protection or be excluded from this proposal? For
    example, the 2400-2402 MHz band is used by the Amateur Satellite
    Service, which we have noted is potentially more vulnerable to
    aggregate interference than other applications.[^52]

40. We seek comment on these proposals, including whether higher power
    operation should be permitted in all frequency bands under Sections
    15.247 and 15.249 of the rules, and whether there should be any
    restrictions on the applications or types of devices that may
    operate at higher power. We also seek comment on whether there are
    any requirements currently in the rules that could be relaxed or
    eliminated for cognitive radio devices. For example, in addition to
    the requirements for spread spectrum devices noted above, Section
    15.247(h) contains a provision that prohibits the synchronization of
    the timing of hop sets in a non-cognitive way to prevent a group of
    devices from monopolizing the use of the spectrum and blocking other
    devices from transmitting.[^53] Could this section be eliminated for
    cognitive devices without adversely affecting spectrum sharing? We
    also seek comment on whether we should exempt devices operating
    under the control of a master controller from complying with DFS or
    other requirements.[^54]

41. We further seek comment on whether higher power operation should be
    permitted for devices operating under any other sections in Part 15.
    For example, Section 15.209 allows operation at a low level in
    almost any frequency band other than the TV bands and certain
    designated restricted bands.[^55] Should higher power operation be
    allowed under that section? We seek comment on whether the increased
    levels we are proposing are sufficient to be of benefit to WISPs,
    wireless LANs or other unlicensed operations in areas with limited
    spectrum use, and how much of an increase in service area these
    levels would allow in practice. We also seek comment on whether
    these power increases are likely to result in interference to other
    users, and the sufficiency of our proposal that TPC be used to
    ensure that these higher power unlicensed devices satisfy the
    applicable power limits -- both inside and outside areas of limited
    spectrum use.

42. We propose that devices operating under the new rule section comply
    with the same harmonic and out-of-band emission limits as devices
    operating under Sections 15.247 and 15.249 of the rules. The current
    harmonic emission limits for devices operating under Section 15.249
    are independent of the in-band power. Theses limits are 500
    microvolts per meter at a distance of three meters for devices
    operating in the 902-928 MHz, 2400-2483.5 MHz and 5725-5875 MHz
    bands, and 2500 microvolts per meter at a distance of three meters
    for devices operating in the 24.0-24.25 GHz band. [^56] The
    out-of-band emission limit for devices operating under Section
    15.249, 50 dB below the in-band emission limit, is a function of the
    in-band field strength.[^57] For devices operating under Section
    15.247, the limit for out-of-band emissions that fall within
    designated restricted bands is also independent of the in-band
    power.[^58] However, the Section 15.247 limit for out-of-band
    emissions that fall outside restricted bands, 20 dB below the
    in-band power, is a function of the in-band power. We seek comment
    on whether we should adjust the limits so that out-of-band emissions
    from equipment operating at higher power levels are no greater than
    the current rules allow. Additionally, we note that the 2400-2483.5
    MHz band is adjacent to the mobile satellite service downlink band
    at 2483.5-2500 MHz. We seek comment on the effect that raising the
    power of unlicensed devices could have on satellite receive
    terminals in the adjacent band.[^59]

43. Also, we note the presence of federal radiolocation operations in
    the 5725-5925 MHz frequency band. The Department of Defense operates
    fixed, transportable and mobile radars that are used primarily for
    surveillance, test range, instrumentation, airborne transponders,
    and experimental testing. These radars are used extensively in
    support of national and military test range operations in the
    tracking and control of manned and unmanned airborne vehicles. Many
    of the installations where these radars operate are located in rural
    areas. We seek comment on the potential effects of our proposal,
    including its cognitive radio safeguards, on such federal
    radiolocation operations

44. As discussed above, we propose that unlicensed devices be permitted
    to operate at higher power in areas with limited spectrum use. We
    propose that limited spectrum use be defined as the authorized band
    of operation, *e.g*., the 2400-2483.5 MHz band, having a certain
    percentage of spectrum unused. We propose to define "unused
    spectrum" for this purpose as spectrum with a measured aggregate
    noise plus interference power no greater than 30 dB above the
    calculated thermal noise floor within a measurement bandwidth of
    1.25 MHz, which is the same value specified for unlicensed PCS
    devices.[^60] We also propose that a device must be able to sense
    across the entire authorized band of operation to determine spectrum
    occupancy before commencing transmissions at higher power. We seek
    comment on these proposals, including the specific percentage of
    spectrum that must be vacant for a band to be considered "empty
    enough" to allow higher power transmission. We seek comment on the
    specific 30 dB monitoring threshold level proposed in these
    bands.[^61] Because some devices that operate in the spread spectrum
    bands hop frequency and may not be on a particular frequency at a
    given instance in time, we seek comment on how long a device must
    sense a band of spectrum to determine it is unused before the device
    can transmit at higher power. We also seek comment on the type of
    receive antenna that should be used in measuring spectrum occupancy,
    whether the proposed monitoring threshold is reasonable and how wide
    a frequency band should be monitored to make this determination. We
    further seek comment on the capabilities a device needs to determine
    when spectrum is empty enough, whether the required capabilities are
    achievable now or in the near future, and whether they could be
    economically incorporated into devices.

45. We propose to require that unlicensed devices operating at higher
    power levels continue to comply with the current RF safety
    requirements.[^62] We recognize that although it may be relatively
    easy for a WISP provider to increase its power, for instance, from a
    central base station, a user's ability to increase its power on the
    return path may be constrained due to battery or RF safety issues.
    However, the use of properly designed sectorized receive antennas,
    coupled with their inherent gain, at the central site could overcome
    this perceived limitation. We seek comment on whether there are any
    possible problems with unlicensed devices operating at higher power
    levels meeting the RF safety limits.

46. It seems apparent that allowing some devices in a band to operate
    with higher power could block the use of lower power devices,
    resulting in a situation where certain devices would not be able to
    operate. We therefore seek comment on whether a device operating at
    higher power should have to re-sense spectrum use at periodic
    intervals to determine whether other users are attempting to
    transmit. If so, how often should it re-sense? Would such a
    requirement have undesirable effects, such as requiring a WISP to
    lower power or turn off completely, and possibly lose a connection
    when another device such as a cordless telephone comes on the air,
    or causing users of lower power devices to simply cease operating if
    they received interference? Alternatively, should there be a
    requirement for devices operating at a higher power level to shut
    down for some period of time at a set interval to allow an
    opportunity for other devices to access spectrum? If so, what would
    be the appropriate time intervals?

47. We seek comment on alternative methods, such as geo-location, that a
    device could use to determine if it is in a rural area, and whether
    a combination of techniques should be required. If a cognitive radio
    device relied on geo-location, we would defer to WTB Docket No.
    03-202 for an appropriate definition of rural area.[^63] We seek
    comment in this docket on the positional accuracy necessary if a
    geo-location technology such as GPS were used. How would a device
    using geo-location access a table or database showing where
    operation is permitted, and who would be responsible for maintaining
    the database? Should the geo-location technology be required to be
    incorporated within the device? How would the device react if it
    were unable to determine its exact position, for example, if it were
    to be indoors? Could some surrogate method, such as measuring the
    number of AM or FM broadcast signals in an area prove useful as an
    alternative optional method for identifying an area that is sparsely
    populated from a spectrum perspective where higher power operation
    could be permitted? We also seek comment on whether alternative
    approaches such as registration should be permitted to authorize
    operation under higher power limits in rural areas. Finally, we seek
    comment on whether there are any special enforcement issues when
    cognitive radio technologies are used to permit the higher power
    operation we have proposed.

## Application: Secondary Markets

### General

48. We recently took several steps in the *Secondary Markets Report and
    Order and Further Notice (Secondary Markets Order*) to facilitate
    and streamline the ability of spectrum users to gain access to
    licensed spectrum by entering into spectrum leasing arrangements on
    reasonable market-driven terms between the private parties.
    Specifically, we adopted rules to remove regulatory uncertainty and
    establish clear policies and rules concerning leasing arrangements.
    In many Wireless Radio Services, licensees are now free to enter
    into voluntary leasing transactions with spectrum users seeking
    access to a licensee's spectrum.[^64] While the flexible framework
    facilitating spectrum leasing arrangements does not impose any
    special technical requirements or constraints on such transactions,
    in some cases these arrangements may be made easier through the use
    of emerging technologies like cognitive radio. As discussed in our
    *Secondary Markets Order*, the ability of potential spectrum lessees
    to identify available leasing opportunities and negotiate with
    licensees, *e.g., access mechanism*, is important for successful
    secondary market transactions.[^65] Also, mechanisms to ensure that
    licensees can reclaim their spectrum from spectrum lessees, *e.g.,
    reversion mechanisms*, are an important consideration for many
    licensees. The *Further Notice* portion of the *Secondary Markets
    Order* seeks comment on changes needed in licensing policies or in
    the provision of licensing information to facilitate development of
    such a secondary marketplace in spectrum. The *Further Notice* also
    acknowledged the Commission's plans to conduct a separate proceeding
    on cognitive radio that might, *inter alia*, address the issue of
    technical requirements for possible leasing of public safety
    spectrum.

49. A cognitive radio could incorporate mechanisms that would enable
    voluntary spectrum leasing transactions between licensees and
    potential lessees that would not otherwise be possible without such
    technology. Such leasing is currently permitted for a significant
    number of non-public safety Wireless Radio Service licensees, but
    subject to potentially prohibitive transaction costs. Cognitive
    radio technology could possibly drive transaction costs to a lower
    level by automating some or all of the process of negotiating the
    terms of a lease. A lease could specify the frequencies available,
    power levels, locations where the spectrum could be used and time
    limits on use, and the radio could ensure that the terms are met.
    While we expect that these capabilities would typically be used in
    the context of a prior leasing arrangement between the parties
    involved, cognitive radio technology could eventually allow
    licensees and potential lessees to negotiate for leased spectrum use
    on an *ad hoc* or real-time basis,[^66] without the need for prior
    leasing agreements with all potential lessees (subject, of course,
    to whatever requirements the Commission has imposed on the nature
    and/or filing process for spectrum leases).

50. Licensees and potential lessees could exchange information via a
    communication link identifying the spectrum that would be leased as
    well as the then current terms and conditions for its use. The
    licensee could, in this manner, control access to and keep track of
    third party use of leased spectrum by, for example, an exchange of
    "tokens" sent to the lessee's devices.[^67] Security of such
    transactions can be reinforced using technologies like the modern
    Public Key Infrastructure (PKI) mechanisms used widely by industry
    today. We seek comment on technical methods that might be used to
    provide information necessary for leasing and how a device would
    "enforce" the terms of the lease. Although the Commission may not
    need to adopt specific technical requirements for these mechanisms,
    we seek comment on whether the Commission could reduce uncertainties
    that may inhibit leasing transactions by encouraging voluntary
    technical standards for access to a licensee's spectrum. What
    approaches to facilitating spectrum leasing transactions could best
    achieve the goals of our flexible and market-driven policies for
    spectrum leasing?

### Interruptible Spectrum Leasing 

#### Background 

51. As described above, secondary market arrangements encompass a wide
    variety of transactions. We expect that many licensees will enter
    into leasing arrangements under which they retain only minimal
    rights to access the spectrum for their own use during the term of
    the lease. Other licensees, however, may wish to condition leased
    use of their spectrum on retaining the right to "interrupt" or
    preempt a lessee's use temporarily in order to satisfy their
    particular operational requirements for immediate access,
    reliability, or security. For instance, a licensee may have a
    critical need to access substantial amounts of spectrum, but only
    very infrequently and for limited time periods. Such a licensee may
    well be very interested in leasing its unused spectrum, but only if
    it can assure that its critical needs will continue to be satisfied.
    Cognitive radio technologies would appear to make interruptible
    leasing practical for the first time, and thus open new
    opportunities for licensees to make their spectrum available to
    third parties on a voluntary basis. We would anticipate that
    interruptible spectrum leasing would be particularly relevant to
    possible leasing by public safety licensees, whose responsibilities
    and spectrum usage requirements are likely to demand robust
    technical mechanisms to ensure interruptible spectrum leasing.

52. By way of background, the Commission provides state and local
    jurisdictions with dedicated spectrum to carry out their public
    safety obligations. Pursuant to Part 90 of our rules, the Commission
    licenses and regulates non-federal[^68] radio communications of
    state and local governmental entities and certain other categories
    of activities.[^69] Communications transmitted over public safety
    facilities may include, for example, communications among members of
    a firefighting team, directions to an ambulance crew, or
    coordination among different police and fire agencies responding to
    a regional crisis. The activities supported by public safety
    communications systems rely heavily on the immediate, reliable and
    secure use of spectrum, particularly when safety of life is
    involved. Public safety activities and their associated
    communications needs are by their very nature highly time-critical,
    and characterized by the very high peak-to-average use ratios with
    low average use, discussed above.[^70] Given these constraints, the
    feasibility of leased use of public safety spectrum during periods
    of low usage may depend heavily on the availability of technology to
    ensure that public safety entities would regain immediate access to
    their spectrum when needed for emergency use. Cognitive radio
    technology can provide the technical mechanisms to ensure the leased
    spectrum is instantly and reliably available for public safety use
    during emergencies serve a critical role in making leased use of
    public safety spectrum possible.

53. In the Further Notice portion of the Secondary Markets Order, we
    sought comment on whether to permit public safety licensees to lease
    their licensed spectrum to other entities.[^71] We noted that
    allowing public safety licensees to lease their spectrum had the
    potential to bring a variety of public interest benefits including:
    more efficient use of public safety spectrum, providing an avenue
    for multiple public safety entities to use the same spectrum, and
    providing financial resources to public safety licensees.[^72] We
    also recognized that public safety licensees who chose to enter into
    leasing arrangements would need near-instant access to their full
    spectrum capacity during emergencies. We noted that while public
    safety entities have traditionally used technology that required
    assignment of full-time dedicated spectrum, new technologies might
    allow reliable near-instant access by public safety licensees during
    emergency periods, yet still permit use by lessees at times of low
    public safety demand. We stated our intention to begin a proceeding
    on cognitive radio technologies that would address this topic.[^73]
    While the issue of public safety leasing remains pending in the
    Secondary Markets proceeding, we seek comment below on possible
    approaches for use of cognitive radio to enhance the efficient
    leased use of public safety spectrum.

#### Discussion

54. In this item, we seek comment on potential mechanisms for lessees to
    access spectrum by means of cognitive radio technology that would
    provide licensees with the ability to rapidly regain the use of the
    spectrum when needed. Technology that provides licensees with highly
    reliable and near-instant access to leased spectrum could be
    beneficial to a wide variety of spectrum users, such as satellite,
    cellular, PCS and private radio network licensees, and we
    accordingly are seeking comment generally on what steps might
    facilitate the use of this technology. For instance, specifying the
    technical methods of accessing and reclaiming spectrum could benefit
    both licensees and potential lessees by standardizing equipment
    designs, thus lowering equipment, and therefore transaction, costs.
    An important potential application of this framework is to possible
    public safety spectrum leasing, where access to, as well as reliable
    and secure use of, spectrum are critical and the public interest may
    require strong technical assurances. Therefore, with respect to that
    particular application, we are seeking comment *inter alia* on
    whether, if we decide to permit public safety leasing,[^74] we
    should identify one or more specific technical approaches in its
    rules to be employed by lessees, either at the discretion of the
    public safety licensee or on a mandatory basis under our rules.

55. As described in detail below, we focus here on technical measures
    for ensuring return of spectrum to the primary licensee under
    pre-designated conditions. Cognitive radio technologies can be used
    both to identify spectrum that is available for leased use and to
    ensure that it reverts to the licensee under the prescribed
    conditions. In particular, we set forth the details of a "beacon"
    approach that would ensure that licensees would retain real-time
    access to their leased spectrum. Of course, the beacon and other
    approaches described below are not necessarily the only ones that
    could facilitate leased access to spectrum while providing licensees
    with the ability to reclaim it quickly with ultra-high reliability.
    We therefore seek comment on other methods that could achieve the
    same goals, and how these methods should be reflected in our rules.

56. *Access/Reversion Mechanisms*. There are generally two categories of
    access/reversion mechanisms that could be used, those that rely on
    the overt permission of the licensee and others that sense the
    operating environment.[^75] Each mechanism represents a somewhat
    different balance of reliability, security, cost, and complexity.
    Among mechanisms relying on overt exchanges for permission, the
    least complex and possibly most economical to implement are
    mechanisms that would permit a lessee to transmit until the licensee
    signals the user to cease operations. Reliability is limited under
    this approach because a lessee who is unable to receive the signal
    ordering it to cease operation may not properly relinquish use of
    the spectrum. "Handshaking" approaches would offer more reliability
    and security by requiring a lessee to request and receive explicit
    permission to use spectrum before each transmission, but this
    approach increases the complexity of implementation and the large
    number of interactions between the two parties may require the
    dedication of a separate "control" frequency. Reversion mechanisms
    using sensing techniques have tradeoffs. "Listen before talk"
    mechanisms would permit a lessee to transmit whenever it did not
    detect a signal by the licensee on a given channel. This mechanism
    is fallible, however, because the licensee's signal may not be heard
    by the lessee under unfavorable propagation conditions.

57. "Beacon" systems offer more in the way of the robust security and
    reliability features that are essential for interruptible spectrum
    leasing. In a beacon system, the lessee's transmitter must have the
    ability to receive a control signal sent continuously by the
    licensee at times when transmissions by the lessee are permitted.
    The lessee may not commence transmissions if the beacon signal is
    not received, and if the beacon signal is present but then stops
    while the lessee is transmitting, transmissions must cease within a
    specified time interval. The beacon could be an RF signal sent by
    the licensee on a designated control frequency, or it may be a
    signal received over a physical connection such as fiber, copper or
    coaxial cable. If the beacon signal suffers from unfavorable
    propagation or the physical connection is lost and the beacon signal
    is not heard by a lessee, the licensee has "fail-safe" protection
    against interference, because if the lessee cannot hear the beacon
    signal, it must cease transmission.

58. We seek particular comment on the beacon approach, which appears to
    provide the reliability necessary for some leasing arrangements, and
    can incorporate features needed for secure access, yet offers
    reasonable cost and acceptable complexity to implement and maintain.
    For example, applying this approach to a public safety leasing
    scenario, the public safety licensee would have control of the
    beacon and thus could directly regain control of the spectrum when
    needed. The beacon approach also allows a licensee to incorporate
    both access and reversion techniques into a technical solution, if
    it so desires. The lessee's device would have to incorporate the
    capability to check for the beacon signal at prescribed intervals.
    If the lessee's transmitter failed to receive a properly
    authenticated beacon signal for a prescribed time period, it would
    be programmed to assume access is no longer authorized and would
    cease use of the leased spectrum. The licensee would have the
    ability to reclaim the use of its spectrum after the prescribed
    listening period. In addition, the licensee's access, return, or
    reversion of its spectrum would not be impeded by unfavorable signal
    propagation because no explicit order to the lessee is necessary to
    terminate the lessee's use.

59. We also seek comment on how information about permissible leased
    uses of spectrum could be exchanged via a technical mechanism, such
    as a beacon signal, and on the cognitive capabilities that equipment
    used by a lessee must have, such as DFS, TPC and geo-location
    determination, to work with the chosen technical mechanism. For
    example, the negotiation of spectrum leasing opportunities would
    most likely require information about spectrum availability, *e.g*.,
    which channels, scope of authorized service area, and the
    characteristics of the spectrum available, *e.g*., modulation, power
    limits. Other necessary information might include the amount of
    spectrum available, its expected duration, and perhaps its cost.
    Different technical information would be needed depending on the
    nature of the service, frequency bands employed, minimum acceptable
    quality of service requirements, and other characteristics of
    licensed and leased spectrum users. We recognize that some of this
    information might be provided in the negotiation of a long-term
    leasing agreement. However, cognitive radio technology could be
    designed to allow licensees to make this information available on a
    real-time basis and allow automated negotiation of the terms of
    leased access. In any case, any access mechanism would have to be
    consistent with the legal framework providing for secondary market
    transactions in spectrum that we adopt in our separate proceeding on
    secondary markets.

60. We seek comment on technical methods that might be used by a beacon
    approach, including those associated with a real-time automated
    negotiation of leased use rights. In this regard, we describe below
    several specific technical proposals for a beacon mechanism and the
    equipment that could be used by the spectrum lessees. As noted
    above, the beacon need not necessarily be in the form of an RF
    signal, but could be a physical connection like fiber, copper or
    coaxial cable and achieve the same results because the key factor of
    the beacon is the presence of the encrypted signal controlled by the
    licensee. First, under our proposal, the beacon signal would be sent
    either constantly or no less frequently than once per second so
    equipment used by lessees will be able to quickly detect the absence
    of an authorized beacon signal. Second, to protect against
    unauthorized use of spectrum, the beacon would contain information
    on the channel(s) available to prevent unauthorized use of channels
    by lessees. In addition, the beacon would include the time of day
    and an electronic signature to prevent "spoofing," whereby an
    unauthorized third-party originates a rogue beacon signal or
    retransmits an earlier beacon signal.[^76] The beacon's electronic
    signature should be sufficiently robust to make generating a rogue
    signal extremely difficult, *e.g.*, use 128-bit encryption, but we
    seek comment on what level of security would be needed to protect
    against unauthorized use. While we seek comment on the need for the
    Commission to define the technical requirements of beacon signatures
    in order to avoid possible harm from licensees using duplicitous
    signatures, we recognize that ongoing industry efforts towards
    standards, such as for public safety communications, might address
    such issues without need for regulatory oversight. We also seek
    comment whether multiple beacons should be required in the event
    that a licensee wishes to make multiple channels or frequency bands
    available to multiple lessees.

61. Under such a beacon proposal, cognitive devices used by spectrum
    lessees could incorporate these and other technical safeguards to
    ensure that use of the spectrum by the licensee would not be
    compromised. For example, devices would be capable of frequency
    agility to allow operation only on the channels or frequencies
    designated as available by the licensee and avoid operation on any
    other frequencies. We seek comment on other approaches that might be
    used to constrain leased use to authorized channels. We thus seek
    comment on all of the proposals regarding access/reversion discussed
    above and on alternatives that may provide similar levels of
    reliability, security, and implementation complexity.

62. *Public Safety Leasing.* For the reasons summarized above, one
    particularly apt use of interruptible leasing would appear to be
    possible spectrum leasing by public safety entities. We anticipate
    that public safety licensees will seek to condition leased use on
    terms that preserve their unfettered right of access to the leased
    spectrum as appropriate to meet public safety needs. For these
    services, it may be in the public interest to ensure that access and
    reversion can be achieved reliably and in a manner secure against
    unauthorized use, yet without undue complexity and burdensome costs
    for implementers. Furthermore, the public interest may also require
    that the provision of leased use of this licensed spectrum must not
    diminish the ability of these licensees to meet their public
    interest responsibilities. Thus, we seek particular comment in the
    public safety context on the beacon proposal and the other
    access/reversion mechanisms discussed above. One potential approach
    would be to establish a technical model for reliable access to and
    secure reversion of leased spectrum that certain licensees would
    have the option of using to structure their leasing arrangements.
    Alternatively, the Commission could adopt the technical model in the
    form of minimum technical requirements for lessees of public safety
    spectrum. Under either alternative, establishing technical criteria
    for cognitive radio devices to provide for access to and reversion
    of leased spectrum could help to achieve the significant benefits of
    spectrum leasing without detrimentally affecting public safety
    licensees' critical reliance on wireless communications. In any
    case, any technical rules that result from this proceeding with
    respect to leased use of public safety spectrum would be subject to
    the outcome of the *Secondary Markets* proceeding.

63. In addition to seeking comment on the application of technical
    access/reversion models to possible public safety leasing, we also
    seek comment here on particular technical issues that would appear
    to have particular relevance to possible public safety leasing. For
    example, would changes in modulation type or other parameters as
    opposed to a cessation of transmission be sufficient in the event a
    public safety licensee needs to reclaim spectrum? We also anticipate
    that transmitters operated on leased public safety frequencies would
    incorporate TPC so the public safety licensee could specify the
    appropriate operating power, and would be programmed to detect a
    properly authenticated public safety beacon within two seconds or
    cease use of the leased spectrum. We seek comment on these
    proposals, as well as on alternatives to the proposed signal and
    reversion times that could offer acceptable reversion capability to
    the public safety licensee. Additionally, other cognitive radio
    technologies may offer alternative approaches to the proposed beacon
    approach. We seek comment on any alternatives that may also achieve
    our goals, *e.g.,* reliability, security, rapid reversion, etc., for
    public safety spectrum leasing.

64. The speed with which a public safety licensee can reclaim access to
    its licensed spectrum will be an important consideration in any
    reliable public safety reversion mechanism. In many instances,
    public safety use, for example, may not spike within a few seconds
    in response to emergencies but is more likely to grow at a rapid
    non-linear rate. Under such usage, instantaneous reversion may be
    unnecessary, and an appropriate reversion return time may be
    identified. We seek comment on whether and how cognitive radio
    technologies could be employed to permit the "tiering" of leased
    channels, which could make some channels available under a system
    with fast turnaround and other channels with slower turnaround. We
    also seek comment on public safety use and what appropriate minimums
    for time to return and at what rates are needed from usage patterns.
    We seek comment on whether beacon technology would best be
    implemented in multiple-channel trunked base stations; and whether
    one or more channels in such base stations could serve the beacon
    function.  We also seek comment on how use of beacon-based
    technology could guard against interference when, on
    occasion, radios in a given system operate in the direct mode,
    *i.e. *a mobile or portable radio communicating directly with
    another mobile or portable radio without the signals going through
    the base station.

65. We also seek comment specifically on how the goals for public safety
    access to spectrum should be achieved, including any alternative
    features that proposed technical solutions should employ, and on
    other considerations important to addressing the technical aspects
    of public safety spectrum leasing transactions. In this regard, we
    recognize that although public safety licensees would want to retain
    control of any cognitive based technology used to ensure the
    reversion of leased spectrum, the acquisition of the technology may
    be funded by lessee(s), subject to the terms of a negotiated lease.

66. Although these specific issues may be of particular import to
    possible public safety leasing, we also seek comment on them in the
    context of interruptible leasing by licensees other than public
    safety entities.

67. *Other Issues.* We also seek comment on how to ensure that lessees
    of spectrum do not inadvertently transmit outside the licensee's
    authorized area and cause harm to other users. In general, we assume
    that a beacon transmitting in a licensed public safety frequency
    band at the same power level normally used in the band would provide
    coverage over the public safety entity's licensed area. This should
    act as a safeguard against lessee operation beyond the licensed
    service area because the lessee's radio will not be able to receive
    the beacon beyond a certain distance. However, because the coverage
    area of a beacon may not precisely match the licensee's service area
    and could extend beyond the service area, it may be possible for a
    lessee to receive a beacon signal outside the authorized service
    area. We seek comment on whether there are technical mechanisms that
    could be used to ensure that lessees operate only within the
    geographic limitations of the license.

## Other Applications of Cognitive Radio Technology

### Dynamically Coordinated Spectrum Sharing 

68. Cognitive radio devices' awareness of their environment and ability
    to use spectrum in response thereto offer new approaches as well as
    significant benefits for our existing procedures facilitating
    spectrum sharing. Many licensed services and their associated
    devices operate in the same frequency bands by coordinating their
    use to avoid mutual interference. Coordinated use enables more users
    to use a given frequency band than would otherwise be possible
    without coordinated sharing. Below we seek comment on the capability
    of cognitive radio technologies to encourage coordinated spectrum
    sharing under existing and new regulatory frameworks.

69. *Coordination of Licensed Operations*. Under current policies,
    co-frequency spectrum sharing among licensed services is usually
    accomplished with formalized procedures. These "prior coordination"
    procedures generally require applicants and licensees to identity
    and address the interference potential of their proposed spectrum
    use with incumbent users in an engineering analysis performed prior
    to filing an application.[^77] Typically these engineering analyses
    are based on "worst case" assumptions, even if the "worst case"
    occurs relatively infrequently. Prior coordination approaches are
    generally practical and spectrally efficient when sharing conditions
    do not change significantly over time. Prior coordinated sharing in
    the C-Band between GSO FSS and terrestrial fixed services (FS) did
    not result in significant underutilized spectrum because early GSO
    earth stations operated with a limited number of transponders on a
    single satellite and both the earth station and the FS facilities'
    directionality remained constant. Today GSO earth stations are
    usually coordinated for more than one satellite orbit position and
    transponder configuration, often called "full-band, full-arc" to
    support business models that supply satellite capacity on demand,
    such as with "teleport" providers, and also ensure systems can
    rapidly respond to satellite failures without interference.[^78]
    Such coordination scenarios may offer opportunities for dynamically
    coordinated spectrum reuse.

70. Informal *ad hoc* sharing mechanisms are often used in frequency
    bands with different services that have unpredictable spectrum use
    patterns. Typically, informal sharing mechanisms rely on local
    frequency coordinators to manually track frequency use in a given
    geographic area and inform parties of frequencies currently not in
    use. Coordination potentially could be made more effective with
    real-time information gathering and automated waveform selection
    made possible by cognitive radio technologies.

71. The benefits that could be gained by relying on cognitive technology
    to facilitate real-time spectrum coordination could become very
    significant as more and varied services share spectrum. Our rules
    often require that new services sharing spectrum with incumbent
    operations coordinate proposed spectrum use with existing
    operations. In many cases, our rules provide a framework for
    sharing, such as between non-geostationary orbit (NGSO) FSS and
    fixed/mobile operations.[^79] NGSO FSS satellites move across the
    sky, requiring that an earth station track and utilize multiple
    satellites to maintain continuity of service. As a result,
    particular frequencies are effectively unused in directions other
    than the instantaneous direction in which an earth station is
    pointed. Using commercially available software tools, information
    about the satellite system and its orbit parameters, sensed
    information about the RF environment, or direct information about
    the satellite system, the direction of the earth stations'
    transmission or reception could be identified, allowing some users
    to share frequencies in directions that could be identified for
    coordinated use.

72. Various cognitive techniques could be used to facilitate
    coordination and increase spectrum reuse by performing necessary
    engineering analysis and other frequency coordination tasks in near
    real-time. We note that our existing framework, and industry
    practices, for NGSO FSS sharing rely on such dynamic coordination
    techniques.[^80] For example, such tools and technologies could be
    used to perform engineering analysis to identify desired to
    undesired signal ratios for terrestrial and satellite links, because
    satellite orbit parameters, desired time period, and locations of
    terrestrial links and earth station are known or calculable. The
    actual occurrence of "worst case" interference conditions could be
    anticipated and avoided by changing terrestrial paths, changing
    satellite uplink or downlink paths, modifying RF parameters, or
    through other techniques. Using cognitive radio technology, one
    could have FS links in areas that would otherwise not be available
    under static coordination procedures (such as within certain
    distances of FSS earth stations). For example, terrestrial
    operations that occasionally operate near NGSO earth stations could
    potentially improve their spectral access by agreeing to employ
    technologies that would anticipate interference and modify or cease
    operations on a given path and reroute traffic via different paths
    (using known poly-grid approaches) to prevent that
    interference.[^81] Alternatively, predicted interference could be
    avoided if the NGSO satellite earth station could change or
    "hand-off" to a different satellite when the NGSO signal path was
    approaching that of the terrestrial fixed system. Thus, by adding
    cognitive radio capabilities in the terrestrial or satellite
    systems, or both, it can become possible to increase spectrum
    sharing beyond what it is otherwise possible. Furthermore, cognitive
    capabilities could improve sharing among terrestrial users as well.

73. We seek comment on ways that we may encourage the use of dynamic
    coordination approaches. For example, what incentives or regulatory
    frameworks for dynamic coordination approaches might facilitate
    satellite and terrestrial coordinated sharing. What coordination
    procedures would be appropriate for terrestrial to terrestrial
    sharing? Could satellite providers employ a spectrum reversion
    mechanism discussed above to permit real-time coordinated use
    without unreasonable risk of interference to their operations? Would
    financial incentives encouraging dynamic coordination approaches be
    warranted? Could our secondary market spectrum leasing provide a
    framework for such financial incentives? Would explicitly making
    dynamic coordination an option in our existing coordination
    procedures be in the public interest?

### Facilitating Interoperability between Communication Systems

74. An important focus of the Commission has been the facilitation of
    interoperability among non-federal public safety entities. Cognitive
    radio technologies offer urgently needed solutions to the
    increasingly crucial interoperability demands facing
    first-responders and other licensed users.[^82] The Act and our
    rules currently provide a regulatory framework for
    interoperability.[^83] This framework includes various Commission
    efforts to facilitate interoperability between non-federal entities
    at the national, regional, state-wide and local level.[^84] Also of
    importance is interoperability between non-federal public safety
    entities and federal government first responders. For instance, the
    Commission has provided for federal government entities' use of 700
    MHz public safety spectrum when used for interoperable
    communications.[^85] In addition, non-federal public safety entities
    sometimes use frequencies allocated to federal government use.[^86]
    The Commission has continued to broaden this framework in the
    context of other proceedings by designating new spectrum for public
    safety interoperable use, for instance in the DTV transition where
    2.6 MHz of the 24 MHz of added spectrum is reserved for public
    safety interoperable use.[^87] Despite these efforts, lack of
    interoperability has been identified as a significant problem in the
    response to several disasters involving multiple jurisdictions, such
    as the September 11, 2001, attack on the Pentagon and the 1982 Air
    Florida crash.[^88] Cognitive radio technologies addressed in this
    proceeding offer a new means of reducing risks to safety of life and
    national security by increasing the opportunities for first
    responders interoperability.

75. Both industry and government bodies are actively addressing the
    complex issues posed by the need for interoperable communication
    between public safety entities. The Public Safety National
    Coordination Committee (NCC) recently made recommendations on
    interoperability and other related issues in their report to the
    Commission.[^89] The Commission's Office of Homeland Security is
    also exploring potential changes to the Commission's technical
    rules, policies, procedures, or practices that would facilitate
    development of cognitive radio technology to enhance public safety
    communications.[^90]

76. Cognitive radio devices' capability to automatically or with some
    user input identify systems and users that need bridging, could
    facilitate interoperability under our existing regulatory framework.
    Devices capable of sensing and identifying signals could dynamically
    respond to new jurisdictions seeking to deploy interoperable
    systems. Devices could, in real time, adapt waveforms received from
    one system and change their modulation formats (such as APCO25 to
    FM) and frequencies and facilitate interoperability with other
    systems. For example, during their response to the Pentagon attack,
    Arlington County Fire's ability to communicate with firemen
    reporting from other jurisdiction would not have been limited to
    their supply of radios to distribute. A device could simply have
    bridged communications from any jurisdictions arriving with their
    own radios. Cognitive radio devices could also be used to connect to
    password protected databases available for public safety use that
    could help identify the kinds of frequencies and waveforms that
    dynamic interoperability would need to bridge.[^91] Devices could
    also perform this interoperability bridging using encryption
    technology when secure communications are required.[^92] Such a
    feature might be very useful for federal entities utilizing secure
    communications systems that assume responsibility for coordinating
    rescue and response efforts. FBI entities who assume control of
    coordinating such efforts may need to bridge from secure
    communication systems in order to communicate with certain
    non-federal entities. Cognitive radios may also contribute to the
    provision of E911 by providing a bridge between systems using
    different air interfaces to provide wireless E911 services. We seek
    comment on how cognitive radio technologies can facilitate
    interoperability between systems. We also seek comment on any rule
    changes necessary to take advantage of these benefits for
    interoperability between systems.[^93] We also seek comment on how
    cognitive radio technologies can provide support to wireless E911
    services.

### Mesh Networks

77. Emerging technologies, such as "mesh" networks, rely on each node in
    an RF network to collect and disseminate information and optimize
    spectrum use by relaying messages through the RF network.[^94] We
    seek comment on the application of this technology and possible rule
    changes needed to facilitate the use of these technologies.

78. In a mesh network, each transmitter interacts on a peer-to-peer
    basis with other nearby transmitters, while also sending and
    receiving messages mimicking a router that relays messages to and
    from neighboring transmitters. Through this relaying process, a
    message can be routed through other transmitters to its destination
    based on the current conditions of the network. The received power
    at an antenna is reduced as the distance from a transmitter
    increases, and thus more power is required to transmit to a receiver
    farther away. Mesh networks function by "whispering" at low power to
    a neighbor rather than "yelling" at a high-power to a node far away.
    This approach may be spectrally more efficient than simply
    transmitting directly to a desired receiver at some distance and
    provide for better sharing scenarios. We seek comment how such
    techniques could be applied to facilitate our goals of improved
    spectrum sharing.

79. Mesh networks can allow radio use to expand to areas beyond the
    reach of network base stations, yet enable multiple users to avoid
    interference to each other. This capability could make it possible
    to deploy operations in areas where line of site is obstructed or
    unavailable and the propagation characteristics of the band would
    otherwise require unobstructed line of site. For example, such a
    capability could be helpful for both licensed and unlicensed
    operations in the microwave bands where common obstructions such as
    trees limit the ability to deploy services with low power. We seek
    comment how this technology might serve our efforts to facilitate
    broadband communication services to consumers, and any rule changes
    that might be necessary. We also seek comment on the impact that
    mesh networks will have on the aggregate interference to licensed
    services.

80. The ability of mesh networks to "self-heal" by responding to
    failures in the network may offer important benefits for ensuring
    network reliability. If one link in a mesh network fails, a message
    can be routed to its destination through alternate links. In this
    way all transmissions from the nodes of a mesh network operate in
    coordinated manner, in the same manner that Internet routers
    intelligently respond to outages by routing traffic around failures.
    We seek comment on how such capabilities could improve the
    reliability of wireless operations.

## SDR and Cognitive Radio Equipment Authorization Rule Changes

### Background

81. Most radio transmitters are required to be certified before they can
    be marketed within the United States and Part 2 of the FCC rules
    specifies the procedures for obtaining certification for both
    licensed and unlicensed transmitters.[^95] The certification rules
    require that the equipment be tested to show compliance with the
    applicable technical rules, and that an application, test report and
    certain exhibits be filed with either the Commission or a designated
    Telecommunication Certification Body (TCB).[^96] The rules also
    provide that when any changes are made to the operating frequency
    range, modulation type or maximum output power of an approved device
    the manufacturer must file a new application for certification.[^97]
    The rules permit certain changes to an approved device to be made
    though a "permissive change" procedure. The permissive change rules
    require manufacturers to submit either a streamlined filing or no
    filing and do not require manufacturers to place a new
    identification number on a device.[^98]

82. In 2001, the Commission adopted changes to the equipment
    authorization rules to accommodate the developing software defined
    radio (SDR) technology.[^99] The Commission defined a software
    defined radio as a transmitter in which the operating parameters of
    frequency range, modulation type or maximum output power (either
    radiated or conducted) can be altered by making a change in software
    that controls the operation of the device without making any changes
    in the hardware components that affect the radio frequency
    emissions.[^100] Although this broad definition covers both radios
    that have software imbedded on chips when the software can not be
    readily changed by the user as well as radios that are designed so
    the software can be easily changed after manufacture, the primary
    focus of this item is on the latter category. Possible ways to load
    new software into a radio after manufacture include over the air,
    through a connection to a personal computer or other programming
    device, and by replacement of a card or chip.

83. The SDR rules were intended to make possible for manufacturers to
    obtain approval for changes to the operating parameters of a radio
    resulting from software changes without the need to physically
    re-label a device with a new FCC identification number in the field.
    The Commission made the rules permissive, rather than mandatory,
    thereby permitting a manufacturer the option to his declare a device
    an SDR at the time of filing for certification, but not requiring
    the manufacturer to do so. The Commission adopted the following rule
    changes for SDRs:

-   Established a new streamlined procedure for obtaining approval for
    changes to the operating parameters of SDRs that result from
    changing the software in the device.[^101] The same FCC
    identification number may be used when changes are made to an
    approved device.

-   Allowed a device's FCC identification number to be displayed
    electronically, rather than on a physical label.[^102]

-   Required SDRs to incorporate security features to ensure that only
    software that is part of an approved hardware/software combination
    can be loaded into an SDR. The exact methods are left to the
    manufacturer.[^103]

-   Required manufacturers to supply a copy of the software that
    controls the operating parameters of a radio to the Commission upon
    request.[^104]

84. Although the SDR rules were adopted over two years ago, to date no
    manufacturers have filed applications to certify a device under our
    new SDR rules. However, devices have been certified that would meet
    the Commission's broad definition of an SDR, but the manufacturer
    did not choose to declare them as such at the time of certification.
    We, therefore, do not know whether these devices incorporate
    features to prevent unauthorized changes to the operating parameters
    because there is no requirement to incorporate security features in
    a transmitter that is not declared as an SDR. Thus, we are concerned
    about the potential for parties to make unauthorized changes to
    software programmable radios after they are manufactured and first
    sold which could result in harmful interference to authorized
    services. Further, we note that manufacturers are now developing
    transmitters that are "partitioned" into two or more physical
    sections connected by wires, where one section houses the control
    software and another contains the RF transmission functions.[^105]
    We, therefore, believe it is time to revisit the SDR rules to
    determine if changes are needed concerning whether the SDR rules
    should be permissive or mandatory, the types of security features
    that an SDR must incorporate, and the approval process for SDRs that
    are contained in modular transmitters.

### Proposals for Part 2 rule changes

85. *Submission of radio software*. The rules requires the applicant,
    grantee, or other party responsible for compliance of an SDR to
    submit a copy of the software source code that controls the device's
    radio frequency operating parameters to the Commission upon
    request.[^106] This requirement is analogous to the requirement to
    supply photographs and circuit diagrams for hardware based devices
    and was added to assist in enforcement by allowing the Commission's
    staff to obtain information it could examine to determine if
    unauthorized changes had been made.

86. Because of the expected complexity and variations in the programming
    languages of the software used to control radio operating
    parameters, examining radio software is unlikely to be an effective
    way to determine whether unauthorized changes have been made to a
    device. Source code generally can not be directly compared to the
    software loaded within a device because the source code is compiled
    before loading and additional changes to the code may be made in the
    loading process. Even if there were a way to compare software,
    manufacturers are permitted to make changes to the software that
    have no effect on the operating parameters at any time without
    notice to the Commission, and it could prove difficult for the
    Commission's staff to determine whether such changes affect the
    compliance of a device. A high level description of the radio
    software and flow diagram of how it works would be more useful in
    understanding the operation of a device than a copy of the software.
    We therefore propose to delete the requirement that grantees or
    applicants supply a copy of their radio software upon request, and
    propose to add a less burdensome requirement that applicants supply
    a description and flow diagram of the software that controls the
    radio operating parameters. The existing requirement in the rules
    that certified equipment must comply with the applicable technical
    rules appears to be a sufficient safeguard against unauthorized
    changes to equipment.[^107] Further, the rules require that an
    applicant or grantee supply a sample of a device to the Commission
    upon request that we can test to determine if a device is
    compliant.[^108] Grantees are also required to maintain records of
    equipment specifications and any changes that may affect compliance,
    which must be made available for inspection by the Commission.[^109]

87. *Applicability of SDR Rules*. As noted above, the current rules
    allow a manufacturer to declare that a particular radio is an SDR
    when the application for equipment authorization is filed, but
    currently do not require this declaration. By not declaring a radio
    as an SDR, the manufacturer is not required to incorporate the
    necessary security features to ensure that only software that is
    part of an approved hardware/software combination can be loaded.
    This means that a radio can be potentially modifiable, and perhaps
    easily so, to operate with parameters not permitted by the rules, or
    to operate outside those that were approved for the device, thus
    increasing the risk of interference to authorized radio services.
    However, not all radios that meet the broad definition of an SDR are
    easily modifiable after manufacture. For example, many radios
    incorporate software on chips that can not be reprogrammed or easily
    replaced by a user.

88. We seek comment on the need for a requirement that
    manufacturers/importers declare certain equipment as SDRs, including
    the benefits of such a requirement in reducing interference and its
    possible burdens on manufacturers. We also seek comment on the types
    of devices to which this requirement should apply, including how the
    rules should distinguish between transmitters that must be
    identified as SDRs and those that need not be. Our goal for such a
    requirement is to minimize the possibility of unauthorized operation
    of software programmable radios, yet avoid imposing new requirements
    on manufacturers whose equipment meet the definition of SDR but are
    designed in a manner such that the transmission control software is
    not easily modified. For example, should we require that
    transmitters into which software can be loaded to change the
    operating parameters after manufacture be declared as SDRs, and that
    they comply with the requirements for SDRs, including incorporation
    of a means to prevent unauthorized software changes? Should this
    requirement apply to transmitters in which the software can be
    modified through means such as a physical interface to a personal
    computer or other device, an over-the-air download, use of a keypad
    or buttons on the device, or by replacing a board, card or chip that
    is not permanently attached to the device? Should this requirement
    apply to radios that can only be reprogrammed by the manufacturer or
    service center using proprietary software that has some form of
    security protection?

89. We further seek comment on whether a requirement to declare certain
    devices as SDRs should apply to transmitter modules. The Commission
    recently proposed in a separate proceeding providing manufacturers
    additional flexibility for authorization of transmitter modules that
    are partitioned into separate radio front ends and firmware provided
    they use digital keys to ensure that only a radio front end and
    firmware that have been certified together may operate
    together.[^110] Would the proposed partitioning and digital key
    requirements for transmitter modules be sufficient to protect
    against unauthorized software modifications of modules and eliminate
    the need to require modules to be declared as SDRs?

90. Equipment used by amateur radio operators is generally exempt from a
    certification requirement.[^111] We have maintained this policy to
    encourage innovation and experimentation in the Amateur Radio
    Service.[^112] However, we are concerned that it may be possible for
    parties to modify SDRs marketed as amateur equipment to operate in
    frequencies bands not allocated to the Amateur Radio Service if
    appropriate security measures are not employed. However, we do not
    wish to prevent licensed amateurs from building or modifying
    equipment, including SDRs that operate only in amateur bands in
    accordance with the rules. Accordingly, we propose that manufactured
    SDRs that are designed to operate solely in amateur bands are exempt
    from the mandatory declaration and certification requirements,
    provided the equipment incorporates features in hardware to prevent
    operation outside of amateur bands. We seek comment on this
    proposal.

91. At present there is a clear distinction between radio transmitter
    technology, regulated under Section 2.801(a) of our rules and
    various radio service rules, and personal computer technology,
    regulated in a much less restrictive way under Subpart B of Part 15
    of our rules. However, increasing computer speeds and speeds of
    digital-to-analog converters (DAC)[^113] may well blur this
    distinction. A general purpose computer capable of outputting
    digital samples at rates in the million sample/seconds range or
    higher could be connected to a general purpose high-power,
    high-speed DAC card which could effectively function as a radio
    transmitter. The marketing of such computers, DACs, and software to
    make them interact could undermine our present equipment
    authorization program at the risk of increasing interference to
    legitimate spectrum users since none of them would be subject to the
    normal authorization requirements. At present this is not a problem,
    but we wish to consider modest steps now to help ensure that this
    scenario does not become a serious problem.

92. While such high-speed DACs are presently marketed to the scientific
    community at high unit costs, we are not aware of any which are
    marketed as consumer items. We seek comment on whether we need to
    restrict the mass marketing of high-speed DACs that could be
    diverted for use as radio transmitters and whether we can do so
    without adversely affecting other uses of such computer peripherals
    or the marketing of computer peripherals that cannot be misused. We
    seek comment on one possible approach as well as welcoming
    alternative proposals. Would it make sense to require that
    digital-to-analog converters marketed as computer peripherals
    that 1) operate at more than one million digital input
    samples/second, 2) have output power levels greater than 100 mW
    and, 3) have an output connector for the analog output be limited in
    marketing to commercial, industrial and business users as we require
    for Class A digital devices? Would it be preferable to characterize
    such systems in terms of output frequency and bandwidth rather than
    input sampling rate? What sampling rate and power limits would be
    needed to avoid impacting DACs that might have a legitimate consumer
    use such as, for video systems and other media applications? Is
    there a practical way to incorporate security features that would
    limit the frequency range or other operating parameters of these
    devices? We also seek comment on the specific types of devices that
    would be affected and the potential burden on manufacturers.

93. *Security and authentication requirements*. The rules require that
    manufacturers take steps to ensure that only software that is part
    of an approved hardware/software combination can be loaded into an
    SDR.[^114] The software must not allow the user to operate the
    transmitter with frequencies, output power, modulation types or
    other parameters outside the range of those that were
    approved.[^115] Manufacturers may use authentication codes or any
    other means to meet these requirements, and must describe the
    methods in their application for equipment authorization.[^116] In
    adopting these requirements, the Commission stated that it may have
    to specify more detailed security requirements at a later date as
    SDR technology develops.[^117]

94. We seek comment on whether any modifications are necessary to the
    security and authentication requirements in the rules. Specifically,
    we seek comment on whether the current rules provide adequate
    safeguards against unauthorized modifications to SDRs. We also seek
    comment on whether more explicit security requirements are
    necessary, such as requiring electronic signatures in software to
    verify the software's authenticity. We further seek comment on what
    should happen in the event that reasonable security methods
    ultimately are broken. Should there be limits to a manufacturer's
    responsibility if, for example, the manufacturer follows an accepted
    industry standard for security?[^118] If manufacturers'
    responsibility is limited, how would the Commission enforce its
    rules, *e.g*., if interference occurs, against the users of
    unauthorized software or the creators/distributors of unauthorized
    software? At least one party has proposed rule changes to clarify
    how a manufacturer can comply with the requirements of Section
    2.932(e) of our rules, and to define the standard of care to be
    applied.[^119] We seek comment whether defining compliance using
    "commercially reasonable measures," or some other standard, such as
    "industry accepted practice," would appropriately balance our goals
    for ensuring compliance with our rules and burdens on manufacturers.
    As described above, device with cognitive capabilities may be
    subject to new forms of abuse to which other devices are not
    susceptible. Of course, devices with cognitive capabilities would
    generally require certification by the Commission, and thus are
    subject to the marketing and use restrictions of Section
    2.803.[^120] We seek comment on how we can enable the use of
    cognitive radio technologies, but prevent abuses such as those
    described above. Are there features that could be incorporated into
    devices to help detect attempts to physically tamper with spectrum
    sensing and geo-location technologies built into devices? Could
    devices be designed to detect alterations to control software or
    databases and cease operation if such alterations are detected?

### Proposals for Part 15 rule changes

95. *Automatic frequency selection for unlicensed devices*. Many
    frequency bands where unlicensed operation is permitted are not
    harmonized worldwide. For example, in the United States, unlicensed
    operation is permitted in the 2400-2483.5 MHz band, while in other
    countries operation is permitted in the 2400-2500 MHz band.[^121]
    The 2483.5-2500 MHz band is used for the Mobile Satellite Service
    (MSS) in the United States and is a restricted band under Part 15,
    therefore unlicensed devices are not permitted to transmit in that
    band to prevent interference to the MSS.[^122] Unlicensed
    transmitters are now being manufactured in which the frequency range
    of operation can be software selectable. However, a transmitter can
    not be approved in the United States unless it is capable of
    complying with the technical requirements of the rule part under
    which it will be operated.[^123] Therefore, an unlicensed
    transmitter that is capable of operation outside permitted bands of
    operation under Part 15 of the rules cannot be certified for
    operation in the United States.

96. Manufacturers would like the ability to certify devices to operate
    over a wider frequency range than is permitted in the United States,
    provided the devices incorporate some sort of technology that
    selects the appropriate operating frequency ranges based on the
    country in which they are used. A device could limit its operation
    to authorized frequencies when used in the United States, but could
    operate on additional frequencies as permitted in other countries.
    This approach could allow the production of devices that could be
    used worldwide, or at least in a number of different countries, and
    eliminate the need for manufacturers to produce multiple versions of
    a device for use in different countries.

97. Allowing certification of frequency selectable wireless devices
    could benefit consumers and manufacturers by reducing production
    costs and allowing production of devices that can be used in both
    the United States and other countries. We therefore propose to allow
    certification of Part 15 devices that are capable of operating on
    non-Part 15 frequencies. We propose to require that such devices
    incorporate DFS to select the appropriate operating frequency based
    on the country of operation and must operate on only Part 15
    frequencies when used in the United States. In addition, we propose
    that such devices must incorporate a means to determine the country
    of operation. There are several methods that a device could use to
    make this determination. One is to incorporate geo-location
    capability, such as GPS, combined with a database, to determine the
    device's geographic location. Alternatively, a device could rely on
    information provided by another device to determine the country of
    operation or the permissible frequency band. For example, a device
    such as a wireless LAN card could rely on a network access point to
    select the appropriate operating frequency band. Under that
    scenario, it would be necessary to assure that the network access
    point is capable of determining its location and communicating that
    information to a connected device.

98. We seek comment on this proposal; in particular, the means that a
    device should employ to determine its country of operation and
    select the appropriate operating frequency range. Are there methods
    other than the ones described above that could be employed? How
    should a device respond if it is unable to determine its geographic
    location? If the frequency band or country of operation is
    determined by an external device such as a network access point,
    what specific requirements should apply to different types of
    devices used in a system such as wireless LAN cards and network
    access points? We also seek comment on how to assure that users
    cannot select an unauthorized frequency range or easily modify
    devices to operate in unauthorized frequency ranges. Consistent with
    our proposals above, we seek comment on whether devices in which the
    operating frequency range can be selected through software should be
    required to be declared as SDRs, and therefore required to meet the
    security and authentication requirements for SDRs to prevent
    unauthorized modifications.

### Pre-certification testing requirements for cognitive radios

99. Transmitters must be tested to show compliance with the applicable
    technical requirements before they can be certified. For unlicensed
    transmitters, both the technical requirements and the test
    procedures are specified in Part 15 of the rules.[^124] For
    transmitters used in licensed services, the technical requirements
    are contained in the rule part for a particular service, and the
    test procedures are specified in Part 2 of the rules.[^125] The
    types of tests specified in these procedures include field strength,
    output power, spurious emissions, occupied bandwidth and frequency
    stability.

100. With most transmitters, the output is tested in response to a
     single or limited number of input conditions to show compliance
     with the rules for the service(s) in which they will operate.
     Cognitive radios must also be tested to show compliance with the
     rules for the services in which they will operate, but unlike other
     transmitters it may also be necessary to test the output in
     response to various inputs or various combinations of inputs.
     Because cognitive radios can perform functions not envisioned at
     the time the current rules were developed, it may be necessary to
     specify additional tests to ensure the compliance of cognitive
     radios. The types of tests to be required will vary depending upon
     the types of technical requirements specified for a radio in a
     particular service, and applicants for equipment authorization will
     be required to provide the results of such testing before
     certification is granted. We expect that in the near future, any
     new testing procedures for cognitive radios will be specified at
     the same time as new cognitive radio rules are adopted as we did in
     the proceeding making new spectrum available for unlicensed devices
     in the 5 GHz band. However, it may eventually be necessary to
     establish a more general framework for testing cognitive radios. As
     discussed below, we seek comment on the new types of tests that
     will be required in two broad areas - unlicensed and licensed
     transmitters.

101. *Tests required for unlicensed devices*. As indicated above, we are
     proposing to allow unlicensed transmitters to operate at higher
     power levels in areas with limited spectrum use. In order to make
     the determination as to when higher power operation is permissible,
     the transmitter must have the ability to scan the spectrum to
     determine occupancy. To verify whether a device has the
     capabilities that we ultimately decide are necessary, there are
     potentially a number of specific tests that may have to be
     performed on a specific device. These tests would include:

-   Determine the frequency range that can be scanned by device

-   Measure the scanning resolution bandwidth

-   Determine the sensitivity of the scanning receiver used to examine
    spectrum occupancy

-   Test the ability of the device to correctly determine spectrum
    occupancy based on presence of various standardized input test
    signals.

-   Determine time period to monitor before declaring that the spectrum
    is not occupied.

-   Ensure transmitter power control adjusts to the correct level.

-   Time to revisit a portion of the spectrum to ensure that it is still
    unused.

-   Response time to vacate a portion of the spectrum when it is
    determined that the spectrum is being used.

102. We seek comment on the above tests as well as on any other tests
     that may be needed to assure compliance by unlicensed devices with
     the SDR and any new cognitive radio rules, as well as a more
     detailed description of the measurement procedures that could be
     used. For testing a device's response to various standardized input
     signals, we seek comment on the frequencies, types and levels of
     the signals that should be used. Should there be a series of input
     signal tests required, and if so, what should they be? We also seek
     comment on whether the Commission should develop such test
     procedures or whether they should be developed through an industry
     standards organization such as ANSI.

103. *Tests required for interruptible radios*. We discussed above that
     cognitive radios could conceivably share spectrum with other
     services, such as public safety or commercial users. Such sharing
     could be facilitated by use of a reversion mechanism, as proposed
     for public safety frequencies, that causes the cognitive radio to
     cease transmission when the primary user of the spectrum needs to
     use it. The reversion mechanism could be the loss of a beacon
     signal or there could be some other control signal telling the
     cognitive radio to cease transmission. In order to assure that the
     reversion mechanism works properly, certain new tests may be needed
     for radios using one of these technologies. We seek comment on the
     testing criteria may be appropriate for an RF beacon based system.
     Likewise, we seek comment on what testing criteria may be
     appropriate for beacon systems whose signal is not delivered over
     the air. We seek comment on whether these tests are appropriate,
     and whether additional tests should be required:

-   Ability of the radio to sense a beacon or other control signal on
    the appropriate frequency or from another source.

-   Minimum receive sensitivity for the control signal.

-   Response time to vacate channel when beacon signal is lost or other
    control signal orders cessation of transmission.

104. *Other required tests specific to cognitive radios*. In addition to
     the specific cases described above, there may be a need to
     establish a more general framework for testing cognitive radios. We
     seek comment on the need for the following tests for different
     types of cognitive radio technology.

105. Listen-before-talk systems scan one or more frequency ranges to
     determine whether there are any other users present before
     transmission. The following tests may be appropriate for
     listen-before-talk systems:

-   Determining the frequency band that is scanned by device

-   Measuring the scanning resolution bandwidth

-   Sensitivity of the scanning receiver used to determine spectrum
    occupancy

-   Ability of the device to select an operating frequency and power
    level based the presence of various standardized test input signals.

-   Determine time period to monitor before declaring that the spectrum
    is not occupied.

-   Time to revisit a portion of the spectrum to ensure that it is still
    unused.

-   Response time to vacate a portion of the spectrum when it is
    determined that the spectrum is being used.

We seek comment on the need for these tests and on any other tests that
may be needed for listen-before-talk systems. For testing a device's
response to various standardized input signals, we seek comment on the
frequencies, types and levels of the signals that should be used. Should
we require a series of input signal tests, and if so, how many?

106. Geo-location systems use GPS or some other method to determine the
     transmitter's location. A database can be used to determine the
     transmitter's proximity to other devices that need to be protected
     from interference. The following tests may be necessary for devices
     that use geo-location. We seek comment on the need for these tests
     and for any other tests that may be required for radios that
     incorporate geo-location technology:

-   Ability to correctly identify its location based on GPS or some
    other method

-   Ability to access database to correctly determine location and
    authorized operating parameters of other transmitters in the
    vicinity

-   Device response when geo-location signal is lost or can not be found

107. Cognitive radios may allow transmissions using new or novel
     formats. For example, it may be possible to divide a signal so
     transmissions occur simultaneously using multiple non-contiguous
     frequency blocks.[^126] Such waveforms could potentially result in
     more efficient use of spectrum by allowing small unused blocks of
     spectrum to be "combined" into larger, more useful blocks of
     spectrum. However, this type of technology raises some novel
     measurement issues because the Commission did not envision its use
     when developed the rules. We therefore seek comment on the
     following questions related to this technology.

-   How should the transmit power be measured to determine compliance
    with the power limits? Should the measurement be of the power per
    channel, the total power over all channels, or some other
    measurement?

-   How can the bandwidth be measured?

-   How should the modulation type be defined?

# PROCEDURAL MATTERS

*Initial Regulat*o*ry Flexibility Analysis*

108. As required by the Regulatory Flexibility Act, 5 U.S.C. § 603, the
     Commission has prepared an Initial Regulatory Flexibility Analysis
     (IRFA) of the possible significant economic impact on small
     entities of the policies and rules proposed in this document. The
     IRFA is set forth in Appendix C. Written public comments are
     requested on the IRFA. These comments must be filed in accordance
     with the same filing deadlines as comments filed in response to
     this Notice of Proposed Rule Making as set forth in paragraph 111,
     and have a separate and distinct heading designating them as
     responses to the IRFA.

*Initial Paperwork Reduction Act of 1995 Analysis*

109. This Notice contains either a proposed or modified information
     collection. As part of its continuing effort to reduce paperwork
     burdens, we invite the general public and the Office of Management
     and Budget (OMB) to take this opportunity to comment on the
     information collections contained in this Notice, as required by
     the Paperwork Reduction Act of 1995, Public Law 104-13. Public and
     agency comments are due at the same time as other comments on this
     Notice; OMB comments are due 60 days from date of publication of
     this Notice in the Federal Register. Comments should address: (a)
     whether the proposed collection of information is necessary for the
     proper performance of the functions of the Commission, including
     whether the information shall have practical utility; (b) the
     accuracy of the Commission's burden estimates; (c) ways to enhance
     the quality, utility, and clarity of the information collected;
     and (d) ways to minimize the burden of the collection of
     information on the respondents, including the use of automated
     collection techniques or other forms of information technology.

110. *Ex Parte Presentations*. This is a permit-but-disclose notice and
     comment rule making proceeding. *Ex parte* presentations are
     permitted, except during the Sunshine Agenda period, provided they
     are disclosed as provided in the Commission\'s rules. *See
     generally* 47 C.F.R. §§ 1.1202, 1.1203, and 1.2306(a).

111. *Filing Comments*. Pursuant to Sections 1.415 and 1.419 of the
     Commission\'s rules, 47 C.F.R. §§ 1.415, 1.419, interested parties
     may file comments on or before [\[]{.underline}75 days from
     publication in Federal Register[\]]{.underline}, and reply comments
     on or before [\[]{.underline}105 days from publication in Federal
     Register[\]]{.underline}. Comments may be filed using the
     Commission\'s Electronic Comment Filing System (ECFS) or by filing
     paper copies. See Electronic Filing of Documents in Rulemaking
     Proceedings, 63 Fed. Reg. 24121 (1998).

112. Comments filed through the ECFS can be sent as an electronic file
     via the Internet to <http://www.fcc.gov/cgb/ecfs/>. Generally, only
     one copy of an electronic submission must be filed. If multiple
     docket or rulemaking numbers appear in the caption of this
     proceeding, however, commenters must transmit one electronic copy
     of the comments to each docket or rulemaking number referenced in
     the caption. In completing the transmittal screen, commenters
     should include their full name, U.S. Postal Service mailing
     address, and the applicable docket or rulemaking number. Parties
     may also submit an electronic comment by Internet e-mail. To get
     filing instructions for e-mail comments, commenters should send an
     e-mail to <ecfs@fcc.gov>, and should include the following words in
     the body of the message, \"get form .\" A sample form and
     directions will be sent in reply. Parties who choose to file by
     paper must file an original and four copies of each filing. If more
     than one docket or rulemaking number appear in the caption of this
     proceeding, commenters must submit two additional copies for each
     additional docket or rulemaking number.

113. Filings can be sent by hand or messenger delivery, by commercial
     overnight courier, or by first-class or overnight U.S. Postal
     Service mail (although we continue to experience delays in
     receiving U.S. Postal Service mail).

114. The Commission\'s contractor, Natek, Inc., will receive
     hand-delivered or messenger-delivered paper filings for the
     Commission\'s Secretary at 236 Massachusetts Avenue, N.E., Suite
     110, Washington, D.C. 20002.

> -The filing hours at this location are 8:00 a.m. to 7:00 p.m.
>
> -All hand deliveries must be held together with rubber bands or
> fasteners.
>
> -Any envelopes must be disposed of before entering the building.
>
> -Commercial overnight mail (other than U.S. Postal Service Express
> Mail and Priority Mail) must be sent to 9300 East Hampton Drive,
> Capitol Heights, MD 20743.
>
> -U.S. Postal Service first-class mail, Express Mail, and Priority Mail
> should be addressed to 445 12th Street, SW, Washington, D.C. 20554.
>
> -All filings must be addressed to the Commission\'s Secretary, Office
> of the Secretary, Federal Communications Commission.

115. Parties who choose to file by paper should also submit their
     comments on diskette. Such a submission should be on a 3.5-inch
     diskette formatted in an IBM compatible format using Microsoft Word
     or compatible software. The diskette should be accompanied by a
     cover letter and should be submitted in "read only" mode. The
     diskette should be clearly labeled with the commenter's name,
     proceeding (including the lead docket number, type of pleading
     (comment or reply comment), date of submission, and the name of the
     electronic file on the diskette. The label should also include the
     following phrase \"Disk Copy -- Not an Original.\" Each diskette
     should contain only party's pleading, preferably in a single
     electronic file. In addition, commenters must send diskette copies
     to the Commission's copy contractor, Natek Inc., Portals II, 445
     12th Street, SW, Room CY-B402, Washington, DC, 20554.

116. Alternative formats (computer diskette, large print, audio cassette
     and Braille) are available to persons with disabilities by
     contacting Brian Millin at (202) 418-7426, TTY (202) 418-2555, or
     via e-mail to Brian.Millin@fcc.gov. This Notice can also be
     downloaded at <http://www.fcc.gov/oet>.

# ORDERING CLAUSES

117. IT IS ORDERED that, pursuant to Sections 4(i), 302, 303(e), 303(f),
     303(r) and 307 of the Communications Act of 1934, as amended, 47
     U.S.C. Sections 154(i), 302, 303(e), 303(f), 303(r) and 307, this
     Notice of Proposed Rule Making IS HEREBY ADOPTED.

118. IT IS FURTHER ORDERED that, pursuant to Sections 4(i), 302, 303(e),
     303(f), 303(r) and 307 of the Communications Act of 1934, as
     amended, 47 U.S.C. Sections 154(i), 302, 303(e), 303(f), 303(r) and
     307, ET Docket No. 00-47 IS TERMINATED.[^127]

119. IT IS FURTHER ORDERED that the Commission\'s Consumer and
     Governmental Affairs Bureau, Reference Information Center, SHALL
     SEND a copy of this notice, Including the Initial Regulatory
     Flexibility Analysis, to the Chief Counsel for Advocacy of the
     Small Business Administration.

120. For further information regarding this Notice of Proposed Rule
     Making, contact Mr. Hugh L. Van Tuyl, (202) 418-7506, e-mail
     [*Hugh.VanTuyl@fcc.gov*](mailto:Hugh.VanTuyl@fcc.gov) or Mr. James
     Miller, (202) 418-7351, e-mail
     [*James.Miller@fcc.gov*](mailto:James.Miller@fcc.gov).

> FEDERAL COMMUNICATIONS COMMISSION
>
> Marlene H. Dortch
>
> Secretary

[]{#__RefHeading___Toc59412438 .anchor}APPENDIX A: PROPOSED RULE CHANGES

Part 2 of Title 47 of the Code of Federal Regulations is proposed to be
amended as follows:

1.  The authority citation for Part 2 continues to read as follows:

> AUTHORITY: 47 U.S.C. 154, 302a, 303 and 336, unless otherwise noted.

2.  Section 2.944 is proposed to be revised to read as follows.

> § 2.944 Submission of radio software description.
>
> Applications for certification of software defined radios must include
> a description and flow diagram of the software that controls the radio
> frequency operating parameters.

3.  Section 2.1033 is proposed to be revised by adding new paragraphs
    (b)(12) and (c)(18)

> § 2.1033 Application for certification.
>
> \* \* \* \* \*
>
> \(b\) \* \* \*
>
> \(12\) Applications for certification of software defined radios must
> include the information required by §§ 2.932(e) and 2.944.
>
> \(13\) Applications for certification of radios operated pursuant to §
> 90.xxx must demonstrate compliance with the requirements in § 90.yyy.
>
> \(c\) \* \* \*
>
> \(18\) Applications for certification of software defined radios must
> include the information required by §§ 2.932(e) and 2.944.
>
> Part 15 of Title 47 of the Code of Federal Regulations is proposed to
> be amended as follows:

4.  The authority citation of Part 15 continues to read as follows:

> AUTHORITY: 47 U.S.C. 154, 302, 303, 304, 307, 336, and 544A.

5.  A new Section 15.202 is proposed to be added to read as follows:

> § 15.202 Certified operating frequency range
>
> Certification may be obtained for a device that is capable of
> operating on frequencies not permitted by this part, provided the
> device incorporates DFS and operates on only United States frequencies
> when operated in the United States.

6.  A new Section 15.206 is proposed to be added to read as follows:

> § 15.206 Cognitive radio devices

\(a\) Devices operating under the provisions of § 15.247 may operate
with a power level six times greater than the maximum permitted in these
sections under the conditions specified in paragraph (c) of this
section.

\(b\) Devices operating under the provisions of 15.249 may operate with
a field strength level 2.5 higher than the maximum permitted in this
section under the conditions specified in paragraph (c) of this section.

\(c\) Intentional radiators operating may operate at the higher power
limits specified in paragraphs (a) and (b) of this section subject to
the following conditions:

\(i\) Devices must incorporate a mechanism for monitoring the entire
band that its transmissions are permitted to occupy.

\(ii\) Devices must monitor for signals exceeding a monitoring threshold
of 30 dB above the thermal noise power within a measurement bandwidth of
1.25 MHz.

\(iii\) Devices may operate at higher power if signals exceeding the
monitoring threshold are detected in less than XX% of the band in which
they are permitted to operate

\(iv\) Devices must incorporate transmit power control to limit their
power output to no greater than the maximum normally permitted in §§
15.247 or 15.249 when the criteria in paragraph (c)(iii) is not met or
when higher power operation is not necessary for reliable
communications.

7.  A new Section 90.xxx is proposed to be added to read as follows:

> § 90.xxx Secondary Leasing of a Public Safety License

Secondary Leasing of a Public Safety License shall operate subject to
the following minimum reversion technical requirements:

\(1\) Devices operating under this rule must employ mechanisms for the
immediate, reliable, and secure preemption by and reversion to the
primary public safety licensee. Devices must employ such mechanisms as
required to ensure they operate lawfully and in compliance with the
leasing agreements authorized in this part.

\(2\) Devices employing a Beacon Signal Detector mechanism as provided
in section xx.xxx of this part shall be in compliance with the minimum
reversion technical requirements of this rule.

8.  A new Section 90.yyy is proposed to be added to read as follows:

> § 90.yyy Technical Requirements: Beacon Signal Detector Leasing
> Operations

Operations conducted under the rules governing secondary leasing
agreements in § xx.xxx of this part may operate subject to a beacon
system satisfying the following criteria:

\(1\) Public Safety licensees shall transmit a beacon signal no less
frequently than once per second specifying the frequency or frequencies
available for use, the time of day and a secure identifying signature of
the Public Safety Licensee Leasor.

\(2\) Devices operating under § xx.xxx of this part must detect the
Public Safety Licensee's beacon signal or cease operations within two
seconds. Devices must also incorporate a means to select the
transmission frequency specified in the Public Safety Licensee's beacon
signal.

[]{#__RefHeading___Toc59412439 .anchor}APPENDIX B: INITIAL REGULATORY
FLEXIBILITY ANALYSIS

As required by the Regulatory Flexibility Act of 1980, as amended
(RFA),[^128] the Commission has prepared this present Initial Regulatory
Flexibility Analysis (IRFA) of the possible significant economic impact
on a substantial number of small entities small entities by the policies
and rules proposed in this Notice of Proposed Rule Making (Notice).
Written public comments are requested on this IRFA. Comments must be
identified as responses to the IRFA and must be filed by the deadlines
for comments on the Notice provided in paragraph 111 of the item. The
Commission will send a copy of the Notice, including this IRFA, to the
Chief Counsel for Advocacy of the Small Business Administration
(SBA).[^129] In addition, the Notice and IRFA (or summaries thereof)
will be published in the Federal Register.[^130]

**A. Need for, and Objectives of, the Proposed Rules**

In the Notice of Proposed Rule Making section, we propose several
changes to Parts 2, 15 and other Parts of the rules. Specifically, we
propose to:

1\) eliminate the requirement for applicants and grantees of equipment
authorization to supply a copy of the software that controls the
operating parameters of a software defined radio, but add a new
requirement that applicants for equipment authorization supply a
description and flow diagram showing how the radio software operates

2\) require that certain radios that meet the definition of a software
defined radio must be declared as such at the time of filing the
certification application, and that they must incorporate a means to
prevent unauthorized software changes that could change the operating
parameters of the radio.

3\) permit certification of wireless LAN cards that incorporate
additional frequency bands for use in other countries, but limit their
operation to authorized frequencies in the United States,

4\) permit certain unlicensed devices to operate at higher power levels
in areas with limited spectrum use;

5\) allow equipment to be developed that could allow public safety
entities to lease spectrum on a temporary basis but reclaim it
immediately when necessary.

These proposals, if adopted, will prove beneficial to manufacturers and
users of unlicensed technology, including those who provide services to
rural communities. Specifically, we note that a growing number of
wireless internet service providers (WISPs) are using unlicensed devices
within wireless networks to serve the needs of consumers. WISPs around
the country are providing an alternative high-speed connection in areas
where cable or DSL services have been slow to arrive. The higher power
limits proposed herein will help to foster a viable last mile solution
for delivering Internet services, other data applications, or even video
and voice services to underserved, rural, or isolated communities.

These proposals could also benefit public sector entities by allowing
the development of "smart" equipment that could enable the leasing of
public sector spectrum to generate needed revenue, but would contain
safeguards that allow the spectrum to be reclaimed by the public sector
entity in the event of an emergency.

**B. Legal Basis**

The proposed action is authorized under Sections 4(i), 301, 302, 303(e),
303(f), 303(r), 304 and 307 of the Communications Act of 1934, as
amended, 47 U.S.C. Sections 154(i), 301, 302, 303(e), 303(f), 303(r),
304 and 307.

**C. Description and Estimate of the Number of Small Entities To Which
the Proposed Rules Will Apply**

The RFA directs agencies to provide a description of, and, where
feasible, an estimate of the number of small entities that may be
affected by the proposed rules, if adopted.[^131] The RFA defines the
term "small entity" as having the same meaning as the terms "small
business," "small organization," and "small business concern" under
Section 3 of the Small Business Act.[^132] Under the Small Business Act,
a "small business concern" is one that: (1) is independently owned and
operated; (2) is not dominant in its field of operations; and (3) meets
may additional criteria established by the Small Business Administration
(SBA).[^133]

**Radio and Television Broadcasting and Wireless Communications
Equipment Manufacturers**

The Commission has not developed a definition of small entities
applicable to unlicensed communications devices manufacturers.
Therefore, we will utilize the SBA definition application to
manufacturers of Radio and Television Broadcasting and Communications
Equipment. Under the SBA\'s regulations, a Radio and Television
Broadcasting and Wireless Communications Equipment Manufacturer must
have 750 or fewer employees in order to qualify as a small business
concern.[^134] Census Bureau data indicates that there are 1,215 U.S.
establishments that manufacture radio and television broadcasting and
wireless communications equipment, and that 1,150 of these
establishments have fewer than 500 employees and would be classified as
small entities.[^135] The remaining 65 establishments have 500 or more
employees; however, we are unable to determine how many of those have
fewer than 750 employees and therefore, also qualify as small entities
under the SBA definition. We therefore conclude that there are at least
1,150 small manufacturers of radio and television broadcasting and
wireless communications equipment, and possibly there are more that
operate with more than 500 but fewer than 750 employees.

**WISPs and other Wireless Telecommunication Service Providers**

The SBA has developed a small business size standard for Cellular and
Other Wireless Telecommunication, which consists of all such firms
having 1,500 or fewer employees.[^136] According to Census Bureau data
for 1997, in this category there was a total of 977 firms that operated
for the entire year.[^137] Of this total, 965 firms had employment of
1,000 employees or more.[^138] Thus, under this size standard, the
majority of firms can be considered small.

**D. Description of Projected Reporting, Recordkeeping, and Other
Compliance Requirements**

Both licensed and unlicensed transmitters are already required to be
authorized under the Commission\'s certification procedure as a
prerequisite to marketing and importation, and the proposals in this
proceeding would not change that requirement. There would, however, be
several changes to the compliance requirements.

Software defined radios in which the software can be easily changed
after manufacture would have to be declared as software defined radios
at the time the application for certification is filed. This would be a
change from the current process, in which declaring a device as a
software defined radio is optional. A software defined radio must
incorporate security features to prevent unauthorized software changes
that affect the operating parameters, and the applicant must describe
them in the certification application. We do not expect that this would
be a significant compliance burden because manufacturers of radios that
would be affected by this requirement generally already take steps to
ensure the security of the radio software.

Unlicensed transmitters that would be permitted to operate at higher
power in rural and other areas with limited spectrum would have to
incorporate sensing capabilities to ensure that higher power operations
could occur only in areas where it is permitted. The applicant for
certification would have to demonstrate in the application that the
equipment meets the requirements.

E.  **Steps Taken to Minimize Significant Economic Impact on Small
    Entities, and Significant Alternatives Considered**

The RFA requires an agency to describe any significant, specifically
small business, alternatives that it has considered in reaching its
proposed approach, which may include the following four alternatives
(among others): "(1) the establishment of differing compliance or
reporting requirements or timetables that take into account the
resources available to small entities; (2) the clarification,
consolidation, or simplification of compliance and reporting
requirements under the rule for such small entities; (3) the use of
performance, rather than design standards; and (4) an exemption from
coverage of the rule, or any part thereof, for small entities."[^139]

If the rules proposed in this notice are adopted, we believe they would
have a significant economic impact on a substantial number of small
entities because the rules will impose the following costs: 1)
compliance with equipment technical requirements, such as incorporating
cognitive capabilities into devices capable of higher power or
multi-band operation or using a beacon or other mechanism to enable
leased use of spectrum, and 2) compliance with reporting requirements,
such as declaring certain radios as software defined radios and
supplying certain information about the equipment to the Commission.
However, the burdens for complying with the proposed rules would be the
same for both large and small entities. Therefore, there would be no
differential and adverse impact on smaller entities. Further, the
proposals in this *Notice* are beneficial to both large and small
entities. Because we believe that the economic impact of the proposed
rules on smaller entities would be, in this setting, beneficial rather
than adverse, we believe it would be premature to consider specific
alternatives to the proposed rules. However, we solicit comment on any
such alternatives commenters may wish to suggest for the purpose of
facilitating the Commission\'s intention to minimize any adverse impact
on smaller entities.

**F. Federal Rules that May Duplicate, Overlap, or Conflict With the
Proposed Rule**

None.

**SEPARATE STATEMENT OF**

**CHAIRMAN MICHAEL K. POWELL**

*Re: Facilitating Opportunities for Flexible, Efficient, and Reliable
Spectrum Use Employing Cognitive Radio Technologies (ET Docket No.
03-108); Authorization and Use of Software Defined Radios (ET Docket No.
00-47), Notice of Proposed Rulemaking and Order*

Today we take another step forward to improve access and efficiency of
our Nation's spectrum and to provide opportunities beyond today's
horizon. I am pleased to support this item that grew out of the Spectrum
Policy Task Force and that explores the many benefits of smart radio
technology and its real-time processing capabilities. Last week, I had
the pleasure of visiting several high-tech companies and met with tribal
communities that are taking advantage of these new and innovative
technologies.

Recent advances in smart radio technologies have the potential to
provide more innovative, flexible, and comprehensive use of spectrum
while at the same time minimizing the risk of harmful interference. On a
real-time basis, smart radios determine their location or environment,
have the flexibility to select the best frequencies to use, know how to
avoid interference with existing users, and can use vacant spectrum
channels. Not only do they have flexibility to use a variety of
frequencies, they also can understand and transmit in many different
formats.

Smart radio technologies also offer potential solutions to the
increasingly crucial interoperability demands facing public safety
entities and other licensed users to enable them to coordinate response
and recovery efforts and ensure national security. Because they can use
different frequencies and modulation techniques, smart radios could also
translate signals between two different radio systems. This ability may
enable more interoperability between public safety first responders --
so that, in an emergency, firefighters from one jurisdiction could more
effectively communicate with firefighters in another jurisdiction.

Today's Notice of Proposed Rulemaking and Order is part of a larger
effort to expand opportunities for wireless services in rural America.
We recently adopted two Notices of Proposed Rulemakings designed to
foster advanced telecommunications in rural America. First, an NPRM on
how we can clarify rules to minimize regulatory costs and provide
incentives to serve rural markets. And second, an NPRM on modified power
limits, new technologies such as smart antennas, and streamlined
equipment approval.

In this proceeding, we will consider the technical capabilities as well
as proposed changes to the Commission's rules and equipment
authorization processes to accommodate and enable more efficient use of
software defined radio and cognitive radio system technologies. Of
special note is the potential of smart radios to facilitate spectrum
leasing transactions, including possible leasing of public safety
spectrum that would not otherwise be possible without the technology.

The possible uses for smart radios are wide ranging. The challenge
before the Commission is to determine how we can open the door for these
technologies so as not to shut out any of their tremendous potential.

**SEPARATE STATEMENT OF**

**COMMISSIONER MICHAEL J. COPPS**

Re: *Facilitating Opportunities for Flexible, Efficient, and Reliable
Spectrum Use Employing Cognitive Radio Technologies (ET Docket No.
03-108); Authorization and Use of Software Defined Radios (ET Docket No.
00-47), Notice of Proposed Rule Making and Order*

Cognitive radios have the potential to be a powerful tool for increasing
spectral efficiency while keeping interference at acceptably low levels.
So, I hope that this NPRM keeps us moving in the direction of allowing
consumers and companies to take advantage of these new technologies. I
am also eager to explore the idea of allowing higher power levels for
unlicensed technologies in rural areas. The wireless networking
community has been asking for this for a long time now. If higher powers
allow them to bring more service to under-served areas, and more
competition to areas largely bereft of competition, we are already late
to the game. So I'm glad we're moving forward.

Finally, I want to note that while this NPRM examines technologies that
would allow public safety entities such as police departments and fire
companies to lease spectrum to non-public-safety users, I will need to
be convinced that this is a good idea before voting to allow it. While I
want to increase the efficiency of spectrum use in crowded bands, I will
need to see proof that allowing commercial operation in the same bands
relied on by policemen and firemen is safe. And I will need to be
convinced that the lure of big dollar figures from commercial companies
will not lead to states and municipalities living in difficult budget
environments to lease out not only extra spectrum, but also core
spectrum.

**SEPARATE STATEMENT OF**

**COMMISSIONER KEVIN J . MARTIN**

*Re: Facilitating Opportunities for Flexible, Efficient, and Reliable
Spectrum Use Employing Cognitive Radio Technologies (ET Docket No.
03-108); Authorization and Use of Software Defined Radios (ET Docket No.
00-47)*, Notice of Proposed Rulemaking and Order

I am very pleased to support this item, which seeks to facilitate the
development of cognitive or "smart" radio technology. Cognitive radio
technology has truly great potential to improve spectrum access and
efficiency. Among other things, the technology allows for greater
sharing of spectrum. As I have previously discussed, promoting spectrum
sharing is a fundamental part of encouraging efficient spectrum usage.
*See*, *e.g.*, Remarks by Kevin J. Martin to the FCBA Policy Summit &
CLE, *U.S. Spectrum Policy: Convergence or Co-Existence?* (Mar. 5,
2002). While the amount of available spectrum is ultimately limited only
by technology, the spectrum supply currently feels very limited. Sharing
spectrum is a crucial means to get more mileage out of this important
resource. *See id.* Cognitive radio technology allows for greater
spectrum sharing by enabling devices to find and use available spectrum
in different frequencies, times, or spaces. This can be as simple as
frequency hopping in a wireless local area network or as advanced as
DARPA's XG program, which would allow multiple users to share common
spectrum by avoiding conflicts in time, frequency, code, and other
signal characteristics. I am confident that we will see even greater
advances in spectrum sharing through cognitive radio technology, and the
Commission should do what it can to facilitate such advances.

Cognitive radio technology also makes possible improved spectrum access
in rural areas. Many Wireless Internet Service Providers (WISPs) are
using unlicensed spectrum to provide innovative services in rural areas
but are finding it difficult to provide adequate signal coverage because
of our current Part 15 power limits. This item proposes allowing such
providers to increase their power input if they use cognitive radio
technology to avoid interference to other users. I am very supportive of
this proposal, and I look forward to receiving comments.

Cognitive radio technology also has great potential for enabling
interoperability among public safety agencies. Lack of interoperability
has been identified as a significant problem in our response to the
September 11 attacks and in other disasters involving multiple
jurisdictions, and we must all focus on improving interoperability.
Cognitive radio technology can play an important part in that
improvement by enabling devices to bridge communications between
jurisdictions using different frequencies and modulation formats.
Through such a mechanism, a fire department from Long Island could
communicate effectively with a police department from Manhattan even if
they use completely different radio systems. Such interoperability is
crucial to enabling public safety agencies to do their jobs.

Accordingly, for all of these reasons, I look forward to receiving
comment on how we can best promote cognitive radio technology.

**SEPARATE STATEMENT OF**

**COMMISSIONER JONATHAN S. ADELSTEIN**

*Re: Facilitating Opportunities for Flexible, Efficient, and Reliable
Spectrum Use Employing Cognitive Radio Technologies; ET Docket No.
03-108; Authorization and Use of Software Defined Radios (ET Docket No.
00-47), Notice of Proposed Rulemaking and Order*

Earlier this year, I had the privilege of helping the Office of
Engineering and Technology open its workshop on cognitive radio
technologies. At that time, I remarked that cognitive radios can
potentially play a key role in shaping our spectrum use in the future. I
believe that these technologies should lead to the advent of smarter
unlicensed devices that make greater use of spectrum than is possible
today. Cognitive radios may also provide licensees with innovative ways
to use their current spectrum more efficiently, and to lease their
spectrum more easily on the secondary market. I had the opportunity to
see cognitive radios demonstrated during the past year and am just
amazed by their potential.

It is for all of these reasons that I am so pleased this item on
cognitive radios is before us today. I recently restated my interest in
having the Commission make more of an effort to get spectrum in the
hands of people who are ready and willing to use it. This is such a
timely discussion of the very latest radio technologies and of how we
can best harness these developments to improve access to spectrum by
those providers who want to serve underserved areas. Spectrum is a
finite public resource. And in order to improve our country's use of it,
we need to improve access to spectrum-based services, and this effort
will facilitate that process.

I am particularly pleased with our proposal to allow higher power
operation for unlicensed devices operating in rural and other areas of
low spectrum use. We heard last month at our wireless ISP forum that
operators across the country need improved access to spectrum. Improving
access to spectrum can drive broadband deployment deeper and farther
into all parts of America. This item takes such an important step in
making that broadband deployment more of a reality.

I believe that cognitive radios will play an important role in "spectrum
facilitation." That means stripping away barriers -- regulatory,
economic, or technical -- to get spectrum into the hands of operators
serving consumers at the most local levels. Cognitive radios can
literally leapfrog the technical and legal problems that currently
hamper many of today's spectrum access opportunities. Spectrum policy is
a two-sided coin: a framework for innovation on one side, with spectrum
facilitation on the other.

I also find the discussion of interruptible spectrum leasing very
interesting. Such a development may enable previously reluctant
licensees to explore a technological fix to address some of the current
challenges of spectrum leasing. While I remain unsure that we should
actually allow public safety licensees to potentially lease their
spectrum to commercial providers, I appreciate the value in having a
discussion on the technical aspects of interruptible spectrum leasing
and its possible use by public safety licensees.

[^1]: The term cognitive radio technology emerged from the application
    of advanced software techniques to radio processing. Dr. Joseph
    Mitola III, *Cognitive Radio An Integrated Agent Architecture for
    Software Defined Radio, Dissertation*, Royal Institute of Technology
    (KTH) (May 8, 2000) *available at*
    http://www.it.kth.se/\~jmitola/Mitola_Dissertation8_Integrated.pdf.
    Distinctions in the use of this and other terms are emerging to
    describe the variety of problems and techniques of improved spectral
    use. We employ the term cognitive radio in this proceeding to
    describe the adaptive awareness capability of these technologies,
    but recognize that the use of the term is evolving in ways that may
    focus on such aspects as learning or reasoning.

[^2]: *See* *Spectrum Policy Task Force Report* ("*Task Force Report*"),
    ET Docket No. 02-135, November 15, 2002, at p. 13-14. The SPTF was a
    multi-disciplinary team of FCC staff established by FCC Chairman
    Powell in June 2002 to assist the Commission in identifying and
    evaluating changes in spectrum policy that would increase the public
    benefits derived from spectrum use.

[^3]: *See* Commission Docket Created In Connection With OET Workshop on
    Cognitive Radio Technologies ET Docket No. 03-108, *Public Notice*,
    DA 03-1480, (rel. May 2, 2003) (opening ET Docket No. 03-108).

[^4]: This proceeding is complementary to other Commission proceedings
    considering specific uses of cognitive radio technologies including:
    (1) additional spectrum for unlicensed devices in the 5470-5725 MHz
    frequency range, *In the matter of Revision of Parts 2 and 15 of the
    Commission's Rules to Permit Unlicensed National Information
    Infrastructure (U-NII) Devices in the 5 GHz Band*, ET Docket No.
    03-122, *Report And Order*, FCC 03-287 (rel. Nov. 18, 2003) (*U-NII
    R&O*). We are not proposing any changes to the rules adopted in that
    proceeding. (2) additional spectrum for unlicensed devices below 900
    MHz and in the 3 GHz band (the TV broadcast and 3650-3700 MHz
    bands), *In the Matter of Additional Spectrum for Unlicensed Below
    900 MHz and in the 3 GHz Band,* ET Docket No. 02-380, *Notice of
    Inquiry*, 17 FCC Rcd 25632 (2002); and (3) interference temperature,
    *In the matter of Establishment of an Interference Temperature
    Metric to Quantify and Manage Interference and to Expand Available
    Unlicensed Operation in the Fixed, Mobile and Satellite Frequency
    Bands*, ET Docket No. 03-237*, Notice of Inquiry and Notice of
    Proposed Rulemaking,* FCC 03-289 (adopted Nov. 13, 2003).

[^5]: *See In the matter of Authorization and Use of Software Defined
    Radios,* ET Docket No. 00-47, *Report and Order*, 16 FCC Rcd 17373
    (2001).

[^6]: *See In the Matter of Promoting Efficient Use of Spectrum Through
    Elimination of Barriers to the Development of Secondary Markets*, WT
    Docket No. 00-230, *Report and Order and Further Notice of Proposed
    Rule Making*, 18 FCC Rcd 20604 (2003).

[^7]: As discussed below, such telephones must include an automatic
    channel selection mechanism to prevent operation on occupied
    channels.

[^8]: *See* 47 C.F.R. § 15.233(b)(2)(i). We note that with advancements
    in technology, cordless telephones now generally operate in higher
    frequency bands.

[^9]: *See* 47 C.F.R. §§ 15.321 and 15.323.

[^10]: *See* *U-NII R&O*.

[^11]: *See Official Requests from the Federal Communications Commission
    to the Technological Advisory Council*, dated May 26, 1999,
    available at
    [www.fcc.gov/oet/tac/requests.pdf](http://www.fcc.gov/oet/tac/requests.pdf).

[^12]: Reports of the TAC's activities are available at
    <http://www.fcc.gov/oet/tac/meetings2.html>. In addition, copies of
    TAC papers are available at
    [http://www.jacksons.net/tac/First%20Term/index.html#SDR](http://www.jacksons.net/tac/First Term/index.html#SDR).

[^13]: *See Notice of Inquiry* in ET Docket No. 00-47, 15 FCC Rcd 5930
    (2000).

[^14]: *See Notice of Proposed Rule Making* in ET Docket No. 00-47, 15
    FCC Rcd 24442 (2000).

[^15]: *See First Report and Order* in ET Docket No. 00-47, 16 FCC Rcd
    17373 (2001).

[^16]: The SPTF sought comment to identify and evaluate possible
    spectrum policy changes and delivered its report to the Commission
    in November 2002. See "Commission Seeks Public Comment on Spectrum
    Policy Task Force Report," Public Notice, 17 FCC Rcd 24316 (2002)
    and *Task Force Report* at p. 1-2. In this Notice, we use the term
    "cognitive radio" to describe the technologies discussed in the SPTF
    Report to improve spectrum use, including "software defined radio."

[^17]: *See Task Force Report* at 13.

[^18]: *Id.*

[^19]: *Id.* at 14.

[^20]: *Id.* Commenters to the report generally supported exploring the
    benefits of cognitive radio technology in this regard. *See
    generally*, Cingular Wireless, LLC Comments January 27, 2003;
    Cognio, Inc. Comments January 27, 2003; Shared Spectrum Company
    Comments January 27, 2003. Others registered concern that the
    technology was still developmental. *See generally* CTIA Comments
    January 27, 2003; New York Office of Technology Comments January 27,
    2003.

[^21]: *See "*The Office of Engineering and Technology hosting Workshop
    on Cognitive Radio Technologies May 19, 2003," ET Docket No. 03-108,
    *Public Notice* (rel. May 16, 2003). We build on information
    obtained in that workshop in this proceeding.

[^22]: *See Notice of Inquiry* in ET Docket No. 02-380, 17 FCC Rcd 25632
    (2003).

[^23]: Information on the XG program is available at
    [www.darpa.mil/ato/programs/XG/](http://www.darpa.mil/ato/programs/XG/).

[^24]: Five abstract behavior sets have been identified for XG: sensing,
    identification, dissemination, allocation, and use or opportunities.

[^25]: *See* <http://www.darpa.mil/ato/programs/xg/rfcs.htm>.

[^26]: *Id.*

[^27]: *See* Resolution 802, WRC-03, agenda item 1.4. IMT-2000 is a set
    of technical standards developed by the ITU to foster the
    development of third generation (3G) and future advanced wireless
    systems. For a description of the system characteristics and
    capabilities of IMT-2000 systems, see the FCC Staff Final Report,
    "Spectrum Study of the 2500-2690 MHz Band: The Potential for
    Accommodating Third Generation Mobile Systems," March 30, 2001,
    available at <http://www.fcc.gov/3G/>.

[^28]: These issues have been jointly assigned to Working Parties 8A and
    8F.

[^29]: *See, e.g.,* FCC Cognitive Radio Workshop, "Frequency Agile
    Spectrum Access Technologies," Presentation by Mark McHenry, Shared
    Spectrum Company (May 19, 2003).

[^30]: *See* Intel Corporation Reply, ET Docket No. 02-380 at 14-18 (May
    16, 2003); *see also* FCC Cognitive Radio Workshop, "Cognitive Radio
    Technologies in the Public Safety & Governmental Arenas,"
    Presentation by Dr. Mike Marcus, Associate Chief, Office of
    Engineering and Technology, FCC (May 19, 2003).

[^31]: *See* In the Matter of Promoting Efficient Use of Spectrum
    Through Elimination of Barriers to the Development of Secondary
    Markets, *Report and Order and Further Notice of Proposed
    Rulemaking*, FCC 03-113 at 88, 103, para. 232, 291 (rel. Oct. 6,
    2003) (*Secondary Markets R&O/FNPRM)*; Facilitating the Provision of
    Spectrum-Based Service to Rural Areas and Promoting Opportunities
    for Rural Telephone Companies to Provide Spectrum-Based Services,
    *Notice of Proposed Rulemaking*, FCC 03-222 at 27, para. 50 (rel.
    Oct. 6, 2003) (*Rural NPRM*).

[^32]: Hetereomorphic waveforms and other new techniques would allow two
    or more waveforms to co-exist by using different polarity, code,
    orthangonality, etc.

[^33]: *See* 47 C.F.R. § 15.403(g).

[^34]: The Commission has held tutorials discussing the use of feature
    detectors and commenters have described the application of these
    techniques to various spectrum sharing scenarios. *See* John W.
    Betz, PhD, Feature Detection, (Feb. 12 2003), *available at*
    <http://www.fcc.gov/realaudio/presentations/2003/021203/featuredetection.pdf>;
    *see also* Shared Spectrum Company, Hidden Node Problem Discussions,
    *ex parte* (Sep. 25, 2003), *available at*
    <http://fccweb01w/prod/ecfs/retrieve.cgi?native_or_pdf=pdf&id_document=6515182975>.
    Dr. Betz's presentation contains a detailed bibliography of academic
    publications on the subject.

[^35]: The hidden node problem refers to the case of a signal that
    reaches a desired receiver near the sensor, but is undetected at the
    sensor due to local terrain features that block it from the sensor.
    An example might be a TV signal which is received at an antenna on
    top of a building whereas building shadowing prevents a ground level
    radiometric detector from detecting the signal since the signal
    strength in the shadow is very weak. In such a case use of a small
    co-channel transmitter at the sensor site might result in
    interference to the higher TV antenna. The use of a feature detector
    much more sensitive than the TV receiver (which requires a signal
    10-20 dB **above** the noise level) makes this much less likely.

[^36]: In a time division multiple access (TDMA) system, the same
    frequency is shared by multiple users. The frequency is divided into
    time slots, with each user transmitting for one time slot and then
    remaining silent for a specific number of time slots. In a code
    division multiple access (CDMA) system, multiple users can also
    operate simultaneously in a frequency band. Each user's signal is
    coded, which allows a receiver with the corresponding code to hear
    the desired signal. There are many variations of TDMA and CDMA
    systems in use.

[^37]: *See generally* Scott Seidel, Robert Breinig, Robert Berezdivin,
    Adaptive Air Interface Waveform for Flexibility and Performance in
    Commercial Wireless Communications Systems, presentation to the
    World Wireless Research Forum, March 8, 2002.

[^38]: *See generally* John W. Rittinghouse and William M. Hancock,
    *Cybersecurity Operations Handbook* (2003); Limor Elbaz, Using
    Public Key Cryptography in Mobile Phones, White Paper, Discretix
    Technologies Ltd. (October 2002), available at
    <http://www.discretix.com/white_paper_c3.pdf>.

[^39]: *See* 47 C.F.R. § 15.205. Unlicensed devices may not
    intentionally transmit in these bands.

[^40]: *See Task Force Report* at 58.

[^41]: *See generally Rural NPRM* at 7, para. 10.

[^42]: *Rural NPRM* at 27, para. 50.

[^43]: *See generally Rural NPRM* at 7, para. 10.

[^44]: *See* 47 C.F.R. §§ 15.247. The spread spectrum rules allow
    operation in the bands 902-928 MHz, 2400-2483.5 MHz and 5725-5850
    MHz.

[^45]: *See* 47 C.F.R. § 15.249. This section allows operation in the
    bands 902-928 MHz, 2400-2483.5 MHz, 5725-5875 MHz and 24.0-24.25
    GHz.

[^46]: *See* 47 C.F.R. § 15.247(a). Section 15.249 does not contain
    operational requirements comparable to those for spread spectrum
    devices because the maximum power permitted under Section 15.249 is
    significantly lower than the maximum permitted for spread spectrum
    devices, thus significantly reducing the potential for interference.

[^47]: Devices operating under Section 15.249 must comply with field
    strength limits rather than power limits. An increase of 8 dB
    corresponds to a 2.5 times increase in field strength.

[^48]: *See Notice of Proposed Rule Making* in ET Docket No. 03-201, 18
    FCC Rcd 18910 (2003).

[^49]: The power at a receiver is a function of the transmit power, the
    propagation (or path) loss between the transmitter and receiver, and
    the receive antenna gain. That is:

    Received power = transmit power -- path loss + receive antenna gain

    If the transmit power is increased by a factor of six (8 dB), then
    the path loss between the transmitter and receiver could be
    increased by 8 dB and result in the same received power. An 8 dB
    increase in path loss corresponds to an increase in the separation
    distance between the transmitter and receiver by a factor of 2.5,
    assuming no other path losses due to factors such as terrain,
    foliage, buildings or atmospheric conditions. The increase in
    coverage area is proportional to the square of this distance, which
    is a factor of approximately six, assuming an omni-directional
    transmit antenna and a circular coverage area.

[^50]: *See* 47 C.F.R. § 2.106, International footnote 5.150, stating
    that radio communication services operating in certain bands,
    including the 902-928 MHz, 2400-2500 MHz, 5725-5875 MHz and 24-24.25
    GHz bands, must accept interference received from ISM applications.
    The ISM bands are also listed in 47 C.F.R. § 18.301. ISM equipment
    uses radio frequency energy to perform work such as heating or
    lighting rather than communications. *See* 47 C.F.R. § 18.107(c).
    Examples of ISM equipment include microwave ovens, industrial
    heating equipment, and RF lighting devices. Because ISM equipment
    does not perform communication functions, it is not susceptible to
    interference from RF communication devices.

[^51]: We also note that spectrum in the 902-928 MHz band dedicated for
    licensed use by the multilateration Location and Monitoring Service
    (M-LMS) is the subject of a pending petition for rulemaking filed by
    Progeny LMS, LLC. *See* "Wireless Telecommunications Bureau Seeks
    Comment On Petition For Rulemaking Regarding Location And Monitoring
    Service Rules," *Public Notice*, DA 02-817, 17 FCC Rcd 6438 (WTB
    rel. Apr. 10, 2002); *see also* "Wireless Telecommunications Bureau
    Extends Comment Cycle On Petition For Rulemaking Regarding Location
    And Monitoring Service Rules," *Public Notice*, DA 02-1070, 17 FCC
    Rcd 8377 (WTB rel. May 7, 2002) (extending the deadline for comments
    on the petition).

[^52]: *See* Amendment of Parts 2 and 97 of the Commission's Rules to
    Create a Low Frequency Allocation for the Amateur Radio Service,
    *Report and Order*, ET Docket No.02-98, 18 FCC Rcd. 10258 (2003),
    paras.43-44.

[^53]: *See* 47 C.F.R. § 15.247(h). This section states that the
    incorporation of intelligence in frequency hopping spread spectrum
    systems is permitted if it allows the system to individually and
    independently choose and adapt its hopsets to avoid hopping on
    occupied channels. The coordination of frequency hopping systems in
    any other manner for the express purpose of avoiding the
    simultaneous occupancy of individual hopping frequencies by multiple
    transmitters is not permitted.

[^54]: A master device was defined in the U-NII proceeding as a device
    operating in a mode in which it has the capability to transmit
    without receiving an enabling signal. In this mode it is able to
    select a channel and initiate a network by sending enabling signals
    to other unlicensed U-NII devices. *See U-NII R&O* at Appendix C.

[^55]: *See* 47 C.F.R. §§ 15.209 and 15.205. The Commission recently
    proposed to allow unlicensed devices to operate on unused channels
    in the TV bands. That issue will be addressed in a separate
    proceeding. *See Notice of Inquiry* in ET Docket 02-380, 17 FCC Rcd
    25632 (2002).

[^56]: *See* 47 C.F.R. § 15.249.

[^57]: *See* 47 C.F.R. § 15.249(d). This section does not require
    out-of-band emissions to be attenuated below the levels in 47 C.F.R.
    § 15.209.

[^58]: *See* 47 C.F.R. § 15.247(c). Certain bands are designated as
    restricted bands under Part 15 of the rules. Only spurious emissions
    are permitted in restricted bands, and the levels must not exceed
    the emission limits in Section 15.209. *See* 47 C.F.R. §§ 15.205 and
    15.209.

[^59]: The 2483.5-2500 MHz band is a restricted band, and the proposed
    rules would not change the current emission limit in this band.

[^60]: *See* 47 C.F.R. § 15.323(c)(2). This section specifies a
    monitoring threshold of 30 dB above the thermal noise floor for a
    bandwidth equivalent to the emission bandwidth for a device. While a
    precise emission bandwidth is not specified, this section specifies
    channel bandwidths of 1.25 MHz.

[^61]: Other numbers may well be appropriate in bands with other sharing
    scenarios.

[^62]: *See* 47 C.F.R. § 2.1091 and 2.1093.

[^63]: *See generally Rural NPRM* at 7, para. 10.

[^64]: *Secondary Markets R&O/FNPRM* at 37, para. 84.

[^65]: *See generally id.* at 84, paras. 221-23.

[^66]: Academic literature has also described real-time secondary
    markets as "spot markets" in spectrum. *See generally* J. M. Peha
    and S. Panichpapiboon, [\"Real-Time Secondary Markets for
    Spectrum,\"](http://intel.si.umich.edu/tprc/papers/2003/208/RealTimeSecondaryMkt.pdf)
    *Proc. 31st Telecommunications Policy Research Conference (TPRC),*
    Sept. 2003.

[^67]: Token approaches rely on the encrypted exchange of unique
    information used to verify a user's identity when opening and
    maintaining a secure communications exchange. Tokens would provide a
    means of ensuring lessees would only transmit on available
    frequencies when they receive an electronic token authorizing them
    to do so. These tokens would among other things enforce terms such
    as the specific period of time allowed, thus providing PS licensees
    a high confidence that lessees will vacate the spectrum when the
    lease expires. Such technology is used in other resource allocation
    problems, such as in enforcement of software license terms. PKI
    applications facilitate the authentication and exchange of
    information needed for the encryption of secure communications.
    Cognitive radio technologies could facilitate negotiation
    capabilities through the use of such techniques. We discuss the
    encryption techniques involved in greater detail in *infra note*
    Error: Reference source not found.

[^68]: The Commission's statutory authority limits its jurisdiction to
    the regulation of non-federal entities. Use of spectrum by federal
    entities is managed by the National Telecommunications and
    Information Administration (NTIA).

[^69]: *See* 47 C.F.R. § 90.15 (medical services, rescue organizations,
    veterinarians, persons with disabilities, disaster relief
    organizations, school buses, beach patrols, establishments in
    isolated places, communications standby facilities, and emergency
    repair of public communications facilities).

[^70]: *See Spectrum Policy Task Force Report* at 43; Bykowsky, Mark M.
    and Marcus, Michael J., "Facilitating Spectrum Management Reform via
    Callable/Interruptible Spectrum," 2002 Telecommunications Policy
    Research Conference (September 2002) at 15, available at
    [[http://intel.si.umich.edu/tprc/papers/2002/147/SpectrumMgmtReform.pdf]{.underline}](http://intel.si.umich.edu/tprc/papers/2002/147/SpectrumMgmtReform.pdf)
    (*Bykowsky/Marcus Report)*; FCC Cognitive Radio Workshop, "Cognitive
    Radio Technologies in the Public Safety & Governmental Arenas,"
    Presentation by Michael Marcus, Sc. D., Office of Engineering and
    Technology, Federal Communications Commission, at 2, 12 (May 19,
    2003) (*Marcus Cognitive Radio Workshop Presentation*).

[^71]: *See Secondary Markets R&O/FNPRM* at 103-104, para. 291-92.

[^72]: *See Secondary Markets R&O/FNPRM* at 103-104, para. 291-92.

[^73]: *See generally id.* at 87-88, para. 232.

[^74]: As described in text, our consideration of interruptible spectrum
    leasing in this proceeding was contemplated at the time that the
    *Secondary Markets Further Notice* was adopted, and is in no way
    intended to prejudge our decision in that proceeding whether to
    permit leasing by public safety licensees.

[^75]: *See generally* Comments of the Dandin Group, Docket 02-135, July
    8, 2002; Comments of Prof. Jon Peha, Docket 02-135, July 7, 2002.

[^76]: Two methods of encryption could facilitate this approach.
    "Secret-key," or symmetric-key, encryption uses a single "private"
    key for both encryption and decryption that must be exchanged for
    users to securely communicate. "Public-key," or asymmetric-key
    encryption, used in PKI systems, uses two keys, a private key held
    locally, and a public key stored on a key server that used alone can
    enable secure communications. The public-key approach does not
    require the private key be exchanged, making it less susceptible to
    masquerading than the secret-key method. However, public-key
    encryption involves more processing and therefore requires more
    processing power and time to send and receive data. These methods
    are currently used to maintain the security of electronic mail and
    online transactions over the Internet and allow users to send
    messages or exchange confidential information that can not be viewed
    by unauthorized parties.

[^77]: *See generally* 47 C.F.R. §101.103. While the rules in Section
    101.103 apply to the fixed service, other terrestrial services have
    adopted this general approach either through duplication of the
    procedures or direct reference to that section. For BAS, Section
    74.638(b) incorporates by reference the coordination procedures in
    Section 101.103(d). For CARS, Section 78.36 describes the same,
    rather than incorporate by reference, the coordination procedures in
    Section 101.103(d). Likewise, similar rules govern the prior
    coordination of satellite earth stations. *See* 47 C.F.R. §§ 25.203,
    25.251. Frequency coordination is also required in the Private Land
    Mobile Radio Services (PLMRS). *See* 47 C.F.R. § 90.175.

[^78]: While such spot-markets in satellite capacity were not envisioned
    in the 1960's when our coordination approaches were first devised,
    today providers of satellite capacity provide such connectivity even
    on minute by minute basis, across various bands, and through
    numerous satellites.

[^79]: For example, the 1990 proceeding allocating spectrum for FSS
    feeder links in the 27.5-29.5 GHz first presented the instant issue
    of terrestrial and satellite sharing. In that proceeding we
    considered the feasibility of FSS feeder link earth stations
    providing backbone services for Iridium coordinating with existing
    and terrestrial services such as the LMDS services*. See Rulemaking
    to Amend Parts 1, 2, 21, and 25 of the commission's Rules to
    Redesignate the 27.5-29.5 GHz Frequency Band, to Reallocate the
    29.5-30.0 GHz Frequency Band, to Establish Rules and Policies for
    Local Multipoint Distribution Service and for Fixed Satellite
    Service*, CC Docket No. 92-297, *First Report and Order and Fourth
    Notice of Proposed Rulemaking,* FCC 96-311 at 11-12, para. 27 (rel.
    July 22, 1996). The Commission has also allocated NGSO FSS spectrum
    in the Ku-band where NGSO FSS uplink and downlink operations
    coordinate with existing terrestrial. *See generally Amendment of
    Parts 2 and 25 of the Commission's Rules to Permit Operation of NGSO
    FSS Systems Co-Frequency with GSO and Terrestrial Systems in the
    Ku-Band Frequency Range,* FCC 00-418, *First Report and Order and
    Further Notice of Proposed Rule Making,* ET Docket No. 98-206, 16
    FCC Rcd 4096 (rel. Dec. 8, 2000) (*NGSO FSS R&O*). NGSO FSS downlink
    operations share with FS operations in the 10.7-11.7 GHz band, and
    NGSO FSS downlink operations share with BAS and CARS operations in
    most parts of the 12.75-13.25 GHz band. *Id*.

[^80]: To prevent interference when satellites from two NGSO FSS
    satellite systems align above an earth station, such systems
    potentially rely on at least three cognitive capabilities. When such
    an alignment is detected or predicted by an NGSO system, the system
    can avoid interference by using: different frequencies, alternative
    satellites in their respective systems, or alternative
    polarizations. *See* ITU-R S.1431; *In the matter of the
    Establishment of Policies and Service Rules for the
    Non-Geostationary Satellite Orbit, Fixed Satellite Service in the Ku
    Band,* IB Docket No. 01-96, *Report and Order and Further Notice of
    Proposed Rulemaking*, FCC 02-123, 17 FCC Rcd 7841, 7857, para. 53
    (2002).

[^81]: Polygrid, or mesh, networks emphasize the use of multiple nodes
    to create a large number of possible paths to connect two or more
    endpoints. The multiple connectivity of such networks allow
    endpoints to be connected even when some individual links have to be
    turned off to prevent interference to or from NGSO satellite
    systems. *See generally* Harry G. Barker III , David A. Calabrese,
    David A. Garbin, J. Edward Knepley, Dr. Martin J. Fischer, and Dr.
    Gregor W. Swinsky, The Circuit Switched Network Design and Analysis
    Model: A Chronology of Its Development and Use, published in the
    2000 The Telecommunications Review (discussing defense applications
    of polygrid routing features in wireline networks), *available at*
    <http://www.mitretek.org/pubs/telecom/review00/article8.doc>.

[^82]: Wide agreement exists among expert commissions, official reports
    and other documents on the critical need to provide first responder
    and emergency management agencies at the Federal, State and local
    levels with interoperable communications systems to enable them to
    coordinate response and recovery efforts. *See e.g,*
    Intergovernmental Dimensions of Domestic Preparedness, Harvard
    Executive Session Memorandum, Appendix H, Third Annual Report to the
    President and the Congress of the Advisory Panel to Assess Domestic
    Response Capabilities for Terrorism Involving Weapons of Mass
    Destruction; A National Action Plan for Safety and Security in
    America's Cities, The United States Conference of Mayors, December
    2001; Institute for Security Technology Studies at Dartmouth
    College, The First Line of Defense: Tools and Technology Needs of
    America's First Responders in the Aftermath of September 11, 2001,
    available at <http://www.ists.dartmouth.edu/iria/fld/fld_draft.pdf>.

[^83]: Section 154(o) states "\[f\]or the purpose of obtaining maximum
    effectiveness from the use of radio and wire communications in
    connection with safety of life and property, the commission shall
    investigate and study all phases of the problem and the best methods
    of obtaining the cooperation and coordination of these systems." 47
    U.S.C. § 154(o); *see also* 47 U.S.C. § 151. Interoperability among
    public safety systems is defined in Section 90.7 of our rules as
    "\[a\]n essential communication link within public safety and public
    service wireless communications systems which permits units from two
    or more different entities to interact with one another and to
    exchange information according to a prescribed method in order to
    achieve predictable results." 47 C.F.R. § 90.7. Our rules currently
    provide for interoperability in some bands and define standards for
    such communications. *See e.g.* 47 C.F.R. § 90.547 (requiring mobile
    and portable transmitters operating in 764-776 & 794-806 MHz be
    capable of operating on all designated nationwide narrowband
    interoperability channels); 47 C.F.R. § 90.548 (defining technical
    standards for narrowband interoperability channels); 47 C.F.R. §
    90.549 (requiring transmitters operating in 764-776 & 794-806 MHz
    bands be certified as required by general technical requirements for
    Part 90).

[^84]: The frequencies include 2.6 MHz of the 700 MHz band, 5 channels
    in the 800 MHz band, 5 channels in the 150 MHz band (VHF band), and
    4 channels in the 450 MHz band (UHF band). Among these frequencies,
    five channels are designated for nationwide interoperability
    communications. Regional planning committees address a variety of
    interoperability frequency planning at the regional level. Under
    this framework States administer interoperable spectrum on the state
    level. 47 CFR § 90.525(a) ("States are responsible for
    administration of the Interoperability channels in the 764-776 MHz
    and 794-806 MHz frequency bands.").

[^85]: *See e.g.* 47 C.F.R. § 2.103(b).

[^86]: For instance, non-federal responders from Montgomery County,
    Maryland Fire & Rescue; Prince William county, Virginia, Fire &
    Rescue; Virginia State Police; Virginia Department of
    Transportation; and numerous federal responders including the F.B.I.
    and U.S. Park Police Public operate across the entire span of the
    138-174 MHz band. *See* Public Safety Wireless Network Program,
    Answering the Call: Communications Lessons Learned from the Pentagon
    Attack at 7-8 Table 1 and Map 1 (January 2002), available at
    <http://www.pswn.gov/admin/librarydocs7/Answering_the_Call_Pentagon_Attack.pdf>
    (summarizing communication systems used by jurisdictions responding
    to Pentagon attack).

[^87]: *See generally The Development of Operational, Technical and
    Spectrum Requirements for Meeting Federal, State and Local Public
    Safety Agency Communication Requirements through the Year 2010*, WT
    Docket No. 96-86, *First Report and Order and Third Notice of
    Proposed Rulemaking*, 14 FCC Rcd 152 (1998).

[^88]: Interoperability was a serious concern in the response to the
    terrorist attack on the Pentagon. *See* Federal Emergency Management
    Agency, Managing the Emergency Consequences of Terrorist Incidents,
    INTERIM PLANNING GUIDE FOR STATE AND LOCAL GOVERNMENTS 25 n.9. (July
    2002), available at
    <http://www.fema.gov/pdf/onp/managingemerconseq.pdf>.
    Interoperability was also a serious problem for first responders to
    the crash of Air Florida flight 90 in 1982 that resulted in 78
    deaths under the 14^th^ street bridge just miles from the Pentagon.

[^89]: *See* Letter from Kathleen M.H. Wallman to Michael Powell,
    Chairman, Federal Communications Commission, WT Docket No. 96-86
    (July 25, 2003) \[hereinafter NCC *ex parte*\].

[^90]: FCC Homeland Security Action Plan (July 10, 2003), *available at*
    <http://hraunfoss.fcc.gov/edocs_public/attachmatch/DOC-236428A2.doc>.

[^91]: To date, the Commission has declined to require the use of a
    password protected pre-coordination data base in the regional
    planning process. *See* The Development Of Operational, Technical
    and Spectrum Requirements for Meeting Federal, State and Local
    Public Safety Agency Communication Requirements Through the Year
    2010, WT Docket No. 96-86, *Fourth Memorandum Opinion and Order*, 17
    FCC Rcd. 4736, 4737 (2002). However, the NCC urges the Commission to
    review this decision and mandate its use. *See* *NCC ex parte* at 6.

[^92]: Our rules currently permit encrypted communication on all but two
    national channels reserved for interoperability. *See* 47 C.F.R. §
    90.533(a).

[^93]: The NCC recommended that the Commission amend Section 90 of its
    Rules to include a new section titled "Interoperability Channels:
    Administration, Use, Limitations" that would consolidate existing
    rules governing interoperability and any new rules that the
    Commission may adopt in response to the NCC's recommendations. *See*
    *NCC ex parte* at 6.

[^94]: *See* FCC Tutorial, Wireless Ad Hoc Mesh Network Technology, DA
    02-1201, *Public Notice* (rel. May 20, 2002).

[^95]: *See* 47 C.F.R. Part 2, subpart J.

[^96]: *See* 47 C.F.R. §§ 2.1033 and 2.960.

[^97]: *See* 47 C.F.R. § 2.1043(a).

[^98]: *See* 47 C.F.R. § 2.1043(b). There are three classes of
    permissive changes. A Class I permissive change includes minor
    modifications to a device that do not degrade the characteristics
    measured at the time of certification. No filing is required for a
    Class I change. A Class II permissive change includes modifications
    to a device that degrade the characteristics measured at the time of
    certification, although the device must continue to comply with the
    applicable rules. Manufacturers must supply information on the Class
    II changes to the Commission or TCB and must receive an
    acknowledgement from the Commission or TCB that the changes are
    acceptable before the modified equipment may be marketed. A Class
    III permissive change includes modifications to the software in a
    software defined radio that change the frequency, modulation type,
    output power or maximum field strength outside the parameters
    previously approved. Manufacturers must submit a description of the
    Class III changes and test results showing that the equipment
    complies with the applicable rules with the new software loaded to
    the Commission and must receive an acknowledgement that the changes
    are acceptable before the modified equipment may be marketed. TCBs
    are currently not permitted to certify SDRs.

[^99]: *See First Report and Order* in ET Docket No. 00-47, 16 FCC Rcd
    17373 (2001).

[^100]: *See* 47 C.F.R. § 2.1.

[^101]: *See* 47 C.F.R. § 2.1043(b)(3).

[^102]: *See* 47 C.F.R. § 2.925(e).

[^103]: *See* 47 C.F.R. § 2.932(e).

[^104]: *See* 47 C.F.R. § 2.944.

[^105]: For example, a notebook computer may run software that digitally
    generates a radio frequency waveform and sends the data to a
    wireless LAN card that further processes and transmits the radio
    signal.

[^106]: *See* 47 C.F.R. § 2.944. Failure to comply within 14 days may be
    grounds for denial of equipment authorization or monetary
    forfeitures.

[^107]: *See* 47 C.F.R. § 2.931.

[^108]: *See* 47 C.F.R. §§ 2.943 and 2.946.

[^109]: *See* 47 C.F.R. §§ 2.936(a) and 2.938(a). We note that Sections
    303(e) and Section 4(i) of the Communications Act continue to give
    the Commission authority to request data that will assist us in
    carrying out our responsibilities under the Act. *See* 47 U.S.C. §§
    154(i) and 303(e).

[^110]: *See generally In the matter of Modification of Parts 2 and 15
    of the Commission's Rules for unlicensed devices and equipment
    approval*, ET Docket No. 03-201, *Notice of Proposed Rulemaking*,
    FCC 03-223 (rel. Sep. 17, 2003).

[^111]: Amateur radio equipment is exempt from a certification
    requirement, except for external power amplifiers operating below
    144 MHz. Such amplifiers must have no gain in the 26-28 MHz band to
    ensure that they can not be used to amplify the output of
    transmitters operating in the Citizen's Band (CB) Radio Service.
    *See* 47 C.F.R. §§ 97.315 and 97.317.

[^112]: *See* 47 C.F.R. § 97.1.

[^113]: The common personal computer sound card uses a low speed DAC,
    typically about 40,000 samples/second, to produce audio output.

[^114]: *See* 47 C.F.R. § 2.932(e).

[^115]: *Id.*

[^116]: *Id.*

[^117]: *See Report and Order* in ET Docket No. 00-47, 16 FCC Rcd 17373,
    13383 (2001).

[^118]: *See* Vanu Inc. Comment, August 1, 2003.

[^119]: Vanu proposes the following language to clarify compliance with
    47 C.F.R. § 2.932(e):

    > A manufacturer will be deemed to comply with the first sentence of
    > Section 2.932(e) if it has taken measures that are commercially
    > reasonable in light of standards employed in the software defined
    > radio industry and other analogous industries at the time,
    > provided that it has not marketed a device containing a software
    > vulnerability that was publicly known, or known to the
    > manufacturer, at the time of marketing.

    Vanu Inc. Comment, at 2 November 19, 2003.

[^120]: *See* 47 C.F.R. § 2.803.

[^121]: *See* 47 C.F.R. §§ 15.247 and 15.249.

[^122]: *See* 47 C.F.R. §§ 15.205 and 25.202.

[^123]: *See* 47 C.F.R. § 2.915(a)(1).

[^124]: *See* 47 C.F.R. §§ 15.31 through 15.35. These sections specify
    general testing procedures applicable to unlicensed transmitters. In
    addition, some industry procedures such as the ANSI C63.4 procedure
    for measuring emissions from intentional and unintentional radiators
    are incorporated by reference into the rules.

[^125]: *See* 47 C.F.R. §§ 2.1046 through 2.1060.

[^126]: This technology has been referred to as "heteromorphic
    waveforms".

[^127]: *See* paragraph 12 above.

[^128]: ^ ?^ *See* 5 U.S.C. § 603. The RFA, *see* 5 U.S.C. § 601 - 612
    has been amended by the Small Business Regulatory Enforcement
    Fairness Act of 1996 (SBREFA ), Pub. L. No. 104-121, Title II, 110
    Stat. 857 (1996).

[^129]: *See* 5 U.S.C. § 603(a).

[^130]: *See* 5 U.S.C. § 603(a).

[^131]: *See* U.S.C. § 603(b)(3).

[^132]: *Id.* § 601(3).

[^133]: *Id.* § 632.

[^134]: 13 C.F.R. § 121.201, NAICS code 334220.

[^135]: Economics and Statistics Administration, Bureau of Census, U.S.
    Department of Commerce, 1997 Economic Census, Industry Series -
    Manufacturing, Radio and Television Broadcasting and Wireless
    Communications Equipment Manufacturing, Table 4 at 9 (1999). The
    amount of 500 employees was used to estimate the number of small
    business firms because the relevant Census categories stopped at 499
    employees and began at 500 employees. No category for 750 employees
    existed. Thus, the number is as accurate as it is possible to
    calculate with the available information.

[^136]: 13 C.F.R. § 121.201, NAICS code 517212 (changed from 513322 in
    October 2002).

[^137]: U.S. Census Bureau, 1997 Economic Census, Subject Series:
    Information, "Establishment and Firm Size (Including Legal Form of
    Organization), "Table 5, NAICS code 513322 (issued October 2000).

[^138]: *Id.* The census data do not provide a more precise estimate of
    the number of firms that have 1,500 or fewer employees; the largest
    category provided is "Firms with 1,000 employees or more."

[^139]: 5 U.S.C. § 603(c)(1) -- (c)(4).