[Federal Register Volume 66, Number 113 (Tuesday, June 12, 2001)]
[Proposed Rules]
[Pages 31585-31589]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 01-14526]


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FEDERAL COMMUNICATIONS COMMISSION

47 CFR Part 15

[ET Docket 99-231; FCC 01-158]


Spread Spectrum Devices

AGENCY: Federal Communications Commission.

ACTION: Proposed rule.

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SUMMARY: This document proposes to amend the Commission's rules to 
improve spectrum sharing by unlicensed devices operating in the 2.4 GHz 
band (2400--2483.5 MHz), provide for introduction of new digital 
transmission technologies, and eliminate unnecessary regulations for 
spread spectrum systems. We take these actions to facilitate the 
continued development and deployment of new wireless devices for 
businesses and consumers.

DATES: Comments must be filed on or before August 27, 2001, and reply 
comments must be filed on or before September 25, 2001.

ADDRESSES: Comments filed through the Commission's Electronic Comment 
Filing System (ECFS) can be sent as an electronic file via the Internet 
to http://www.fcc.gov/e-file/ecfs.html. Parties who chose to file 
comments by paper should send comments to the Commission's Secretary, 
Magalie Roman Salas, Office of the Secretary, Federal Communications 
Commission, 445 Twelfth Street SW., TW-A325, Washington, DC 20554.

FOR FURTHER INFORMATION CONTACT: Neal McNeil, Office of Engineering and 
Technology, (202) 418-2408, TTY (202) 418-2989, e-mail: 
<a href="/cdn-cgi/l/email-protection#422c2f212c272b2e022421216c252d34"><span class="__cf_email__" data-cfemail="e18f8c828f84888da1878282cf868e97">[email protected]</span></a>.

SUPPLEMENTARY INFORMATION: This is a summary of the Commission's 
Further Notice of Proposed Rule Making and Order, ET Docket 99-231, FCC 
01-158, adopted May 10, 2001 and released May 11, 2001. The full text 
of this document is available for inspection and copying during regular 
business hours in the FCC Reference Center (Room CY-A257), 445 12th 
Street, SW, Washington, DC 20554. The complete text of this document 
also may be purchased from the Commission's duplication contractor, 
International Transcription Service, Inc., (202) 857-3800, 1231 20th 
Street, NW., Washington, DC 20036.

Summary of Further Notice of Proposed Rulemaking and Order

    1. The Further Notice of Proposed Rulemaking and Order (``FNPRM'') 
propose to amend part 15 of the Commission's rules to improve spectrum 
sharing by unlicensed devices operating in the 2.4 GHz band (2400--
2483.5 MHz), provide for introduction of new digital transmission 
technologies, and eliminate unnecessary regulations for spread spectrum 
systems. Specifically, this FNPRM proposes to revise the rules for 
frequency hopping spread spectrum systems operating in the 2.4 GHz band 
to reduce the amount of spectrum that must be used with certain types 
of operation, and to allow new digital transmission technologies to 
operate pursuant to the same rules as spread spectrum systems. It also 
proposes to eliminate the processing gain requirement for direct 
sequence spread spectrum systems, which will provide manufacturers with 
increased flexibility and regulatory certainty in the design of their 
products. We take these actions to facilitate the continued development 
and deployment of new wireless devices for businesses and consumers.
    2. The original Notice of Proposed Rule Making (``NPRM'') 64 FR 
38877, July 20, 1999, in this proceeding, which was initiated in 
response to a request from the Home RF working group, proposed to amend 
the rules to allow frequency hopping spread spectrum systems operating 
in the 2.4 GHz band to use hopping channel bandwidths wider than 1 MHz. 
The NPRM also proposed to adopt a new method for determining compliance 
with the requirement that direct sequence systems exhibit a minimum of 
10 dB processing gain. The First Report and Order (``First R&O'') 65 FR 
57557, September 25, 2000, in this proceeding amended the spread 
spectrum rules to allow frequency hopping spread spectrum transmitters 
in the 2.4 GHz band to use bandwidths between 1 MHz and 5 MHz at a 
reduced power output of up to 125 mW. Frequency hopping systems with a 
bandwidth of up to 1 MHz are required to use at least 75 non-
overlapping hopping frequencies. Use of 75 hopping frequencies is 
generally not feasible for systems having a bandwidth in excess of 1 
MHz because the 2.4 GHz band, which covers 2400-2483.5 MHz, provides 
only 83.5 megahertz of spectrum. Accordingly, the rules were amended to 
permit systems using a bandwidth greater than 1 MHz but less than or 
equal to 5 MHz to use as few as 15 non-overlapping channels provided 
that the total span of hopping channels be at least 75 MHz. Therefore, 
while a system using 5 MHz hopping channel bandwidths is permitted to 
use as few as 15 hopping frequencies, one using 3 MHz hopping channel 
bandwidths must use at least 25 hopping frequencies to comply with the 
rules.
    3. Frequency Hopping Spread Spectrum Systems. Thirteen parties 
filed a Joint Petition for Clarification, or in the Alternative, 
Partial Reconsideration (``Joint Petition'') in response to the First 
R&O requesting that the Commission clarify its rules to specify a 
minimum of 15 hopping channels for any frequency hopping system 
operating in the 2.4 GHz that uses adaptive hopping techniques as 
allowed under 47 CFR 15.247(h) and limits its output power to 125 mW, 
regardless of hopping channel bandwidth. We propose to amend 47 CFR 
15.247 by incorporating the changes proposed in the Joint Petition. 
Interested parties are invited to comment on the acceptability of this 
proposal. Commenters are encouraged to include technical analyses that 
support claims that this change will either improve or degrade sharing 
of this spectrum. We particularly invite comment as to whether use of 
adaptive hopping techniques should be mandatory and how we should 
determine compliance with this requirement when evaluating specific 
devices for purposes of equipment certification. Commenters are also

[[Page 31586]]

encouraged to examine alternative operating parameters or conditions 
that may achieve the same goals. For example, the operating conditions 
in the Joint Petition would allow a system using 1 MHz bandwidth 
hopping channels to use as little as 18% of the available spectrum at 
2.4 GHz to implement adaptive hopping techniques. Could the Commission 
realize the goals of the petitioners by requiring that adaptive hopping 
systems use a minimum of 25% or 50% of the band with a power reduction 
in relationship to amount of spectrum used? Could even fewer hops be 
used efficiently and effectively with a corresponding reduction in 
power? Those commenters who do not agree that the rule changes would be 
beneficial to operation in the 2.4 GHz band should provide an 
explanation.
    4. Digital Transmission Systems. We observe that new digital 
transmission technologies have been developed that have spectrum 
characteristics similar to spread spectrum systems. Indeed, proponents 
of some of these technologies allege that their systems meet the 
processing gain requirement of 47 CFR 15.247(e) for direct sequence 
spread spectrum systems. However, the current rules only provide for 
specific types of spread spectrum technology and do not provide 
latitude to permit other types of technologies that have similar 
spectrum characteristics. We believe that the rules should be modified 
to permit the operation of these alternative digital technologies. We 
propose to amend 47 CFR 15.247 to provide for use of spread spectrum or 
digital technologies. This proposed change would apply for operations 
in the current spread spectrum bands at 915 MHz, 2.4 GHz and 5.7 GHz. 
Digital technologies would be required to meet the same technical 
requirements as spread spectrum systems, as modified in this 
proceeding. We believe that this proposal will allow more and more 
diverse products to utilize those bands and thereby increase consumer 
choice. It would provide the flexibility and certainty needed to 
promote the introduction of new, non-interfering products into the 
band, without the need for frequent rule changes to address each 
specific new technology that may be developed.
    5. The rules for part 15 spread spectrum systems limit maximum peak 
output power to 1 watt. In addition, the rules for direct sequence 
systems limit peak power spectral density conducted to the antenna to 8 
dBm in any 3 kHz band during any time interval of continuous operation. 
This peak power density limit is intended to control interference by 
ensuring that the transmitted energy in a direct sequence system is not 
concentrated in any one portion of the emission bandwidth. In 
considering the appropriate power limits for digital modulation 
systems, it appears that the spectrum characteristics of these systems 
are very similar to the characteristics of direct sequence spread 
spectrum systems. Accordingly, it appears that digital systems may 
exhibit no more potential to cause interference to other devices than 
direct sequence systems. With this in mind, we invite comment on 
whether digitally modulated systems should be allowed to operate at the 
same power levels as direct sequence spread spectrum systems, namely 1 
watt maximum output power with power spectral density not exceeding 8 
dBm in any 3 kHz band. However, we also invite comment as to whether 
the flexibility we are allowing for digitally modulated systems 
warrants a reduction in permitted power levels to reduce the likelihood 
of any adverse impact on other systems operating in this spectrum, 
similar to the reduced power levels adopted for wide-band frequency 
hopping systems. If we find it necessary to reduce the allowed power 
for digitally modulated systems, should we make any changes in the 
power level adjustments for point-to-point operation in 
Sec. 15.247(b)(3)?
    6. The proposals made herein would more closely align the 
Sec. 15.247 rules with the U-NII rules. We seek comment on whether the 
same result would be achieved by amending the U-NII rules to include 
the 915 MHz and 2.4 GHz bands. The upper limit of the 5.725-5.825 GHz 
U-NII band would also need to be expanded to 5.850 GHz in order to 
realign the standards with those presently permitted under Sec. 15.247. 
We specifically invite comment on any detrimental impact this could 
have on manufacturers.
    7. Direct Sequence Processing Gain. The processing gain requirement 
was adopted more than ten years ago as a means to ensure that 
manufacturers would not take advantage of the higher power levels 
afforded spread spectrum devices by designing systems with wide 
bandwidths where much of the energy transmitted is not needed for 
communication. As the spread spectrum industry has matured it is not 
clear that this requirement continues to be necessary. Manufacturers 
have an incentive to design their systems to include processing gain in 
order for their devices to operate properly when located near other 
radio frequency devices. In addition, it has become increasingly 
difficult to determine the true processing gain of certain direct 
sequence spread spectrum systems. We observe that uncertainties about 
the processing gain requirement can be a significant impediment to the 
introduction of new technologies. In light of these factors, we are now 
proposing to eliminate the processing gain requirement for direct 
sequence spread spectrum systems. We invite comment on this proposal.

Initial Regulatory Flexibility Analysis

    8. As required by Section 603 of the Regulatory Flexibility Act,\1\ 
the Commission has prepared an Initial Regulatory Flexibility Analysis 
(IRFA) of the expected significant economic impact on small entities by 
the policies and rules proposed in this Further Notice of Proposed Rule 
Making and Order (Further Notice). Written public comments are 
requested on the IRFA. Comments must be identified as responses to the 
IRFA and must be filed by the deadlines for comments on the Further 
Notice of Proposed Rule Making.
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    \1\ 5 U.S.C. 603.
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A. Need for and Objectives of the Proposed Rules

    9. This Further Notice of Proposed Rulemaking proposes changes that 
remove unnecessary regulatory barriers to the introduction of new 
wireless devices using spread spectrum and other digital technologies. 
The proposals will also improve sharing of the spectrum by wireless 
devices operating in the 2.4 GHz band (2400-2483.5 MHz). Specifically, 
the FNPRM proposes to relax the frequency hopping spread spectrum rules 
in Sec. 15.247 in accordance with a Joint Petition for Clarification, 
or in the Alternative, Partial Reconsideration filed by thirteen 
parties.\2\ The proposed changes would permit all frequency hopping 
systems in the 2.4 GHz band to use as few as fifteen hopping channels 
instead of the seventy-five hopping channels some systems are now 
required to use. Systems using the minimum number of channels will be 
required to employ adaptive hopping techniques in order to avoid 
transmitting on occupied frequencies.
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    \2\ See Joint Petition for Clarification or, in the Alternative, 
Partial Reconsideration filed October 25, 2000 in ET Docket 99-231 
on behalf of 3Comm, Apple Computer, Cisco Systems, Dell Computer, 
IBM, Intel Corporation, Intersil, Lucent Technologies, Microsoft, 
Nokia Inc., Silicon Wave, Toshiba America Information Systems, and 
Texas Instruments.
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    10. The FNPRM seeks comments regarding alternative operating 
parameters or conditions for frequency

[[Page 31587]]

hopping systems that may achieve the same goals. For example, the 
operating conditions in the Joint Petition would allow a system using 1 
MHz bandwidth hopping channels to use as little as 18% of the available 
spectrum at 2.4 GHz to implement adaptive hopping techniques. The FNPRM 
asks whether the Commission could realize the goals of the petitioners 
by requiring that adaptive hopping systems use a minimum of 25% or 50% 
of the band with a power reduction in relationship to amount of 
spectrum used.
    11. The FNPRM also proposes to modify the rules for non-frequency 
hopping spread spectrum systems in the 915 MHz (902-928 MHz), 2.4 GHz, 
and 5.7 GHz (5725-5850 MHz) bands to accommodate developing systems 
that use digital modulation techniques. Systems using digital 
modulation techniques would be required to meet the same technical 
requirements as spread spectrum systems, as modified in this 
proceeding. The Commission believes that this proposal will allow more 
and more diverse products to utilize those bands and thereby increase 
consumer choice. It would also provide the flexibility and certainty 
needed to promote the introduction of new, non-interfering products 
into the band, without the need for frequent rule changes to address 
each specific new technology that may be developed. This proposal would 
more closely align the Sec. 15.247 spread spectrum rules with the 
Sec. 15.407 U-NII rules. Therefore, we seek comment on whether the same 
result would be achieved by amending the U-NII rules to include the 915 
MHz and 2.4 GHz bands.
    12. Finally, the FNPRM proposes to eliminate the processing gain 
requirement for direct sequence spread spectrum systems. The processing 
gain requirement was adopted more than ten years ago as a means to 
ensure that manufacturers would not take advantage of the higher power 
levels afforded spread spectrum devices by designing systems with wide 
bandwidths where much of the energy transmitted is not needed for 
communication. As the spread spectrum industry has matured it is not 
clear that this requirement continues to be necessary. Manufacturers 
have an incentive to design their systems to include processing gain in 
order for their devices to operate properly when located near other 
radio frequency devices.

B. Legal Basis

    13. The proposed action is taken pursuant to Sections 4(i), 301, 
302, 303(e), 303(f), and 303(r) of the Communications Act of 1934, as 
amended, 47 U.S.C. 154(i), 301, 302, 303(e), 303(f), and 303(r).

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

    14. 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.\3\ The Regulatory 
Flexibility Act 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.\4\ A small business concern in its field of operation; and (3) 
satisfies any additional criteria established by the SBA.\5\
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    \3\ 5 U.S.C. 603(b)(3).
    \4\ Id. 601(3).
    \5\ Id. 632.
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    15. The Commission has not developed a definition of small entities 
applicable to unlicensed communications devices manufacturers. 
Therefore, we will utilize the SBA definition applicable to 
manufacturers of Radio and Television Broadcasting and Communications 
Equipment. According to the SBA regulations, unlicensed transmitter 
manufacturers must have 750 or fewer employees on order to qualify as a 
small business concern.\6\ Census Bureau data indicates that there are 
858 U.S. companies that manufacture radio and television broadcasting 
and communications equipment, and that 778 of these firms have fewer 
than 750 employees and would be classified as small entities.\7\ We do 
not believe this action would have a negative impact on small entities 
that manufacture unlicensed spread spectrum devices. Indeed, we believe 
the actions should benefit small entities because it should make 
available increased business opportunities to small entities. We 
request comment on these assessments.
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    \6\ See 13 CFR 121.201, NAICS Code 334220 (SIC Code 3663). 
Although SBA now uses the NAICS classifications, instead of SIC, the 
size standard remains the same.
    \7\ See U.S. Dept. of Commerce, 1992 Census of Transportation, 
Communications and Utilities (issued May 1995), SIC category 3663 
(NAICS Code 334220).
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D. Description of Projected Reporting, Recordkeeping and Other 
Compliance Requirements

    16. Part 15 transmitters are already required to be authorized 
under the Commission's certification procedure as a prerequisite to 
marketing and importation. See 47 CFR 15.101, 15.201, 15.305, and 
15.405. Additionally, manufacturers of direct sequence spread spectrum 
systems must submit a determination of system processing gain to the 
Commission in order to obtain product certification.
    17. The proposed regulations will add permissible methods of 
operation for frequency hopping spread spectrum systems. No new 
reporting or recordkeeping requirements are proposed for the 
manufacturers of frequency hopping spread spectrum devices. However, 
the rules proposed in the Further Notice would eliminate the 
requirement that manufacturers of direct sequence systems submit 
evidence of compliance with a minimum processing gain. Therefore, the 
proposed rules reduce the reporting and recordkeeping burdens placed on 
all manufacturers, including small entities. None of the proposals 
would require alteration of any existing products.

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

    18. The RFA requires an agency to describe any significant 
alternatives that it has considered in reaching its proposed approach, 
which may include the following four alternatives: (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 or reporting requirements under the rule for 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.
    19. At this time, the Commission does not believe the proposals 
contained in the Further Notice will have a significant economic impact 
on small entities. The Further Notice does not propose new device 
design standards. Instead, it relaxes the rules with respect to the 
types of devices which are allowed to operate pursuant to the spread 
spectrum regulations. There is no burden of compliance with the 
proposed changes. Manufacturers may continue to produce devices which 
comply with the former rules and, if desired, design devices to comply 
with the new regulations. The proposed rules will apply equally to 
large and small entities. Therefore, there is no inequitable impact on 
small entities. Finally, the FNPRM does not recommend a deadline for 
implementation. We believe that the proposals are relatively simple and 
do not require a transition period to

[[Page 31588]]

implement. An entity desiring to take advantage of the relaxed 
regulations may do so at any time.
    20. Unless our views are altered by comments, we find that the 
proposed rule changes contained in this FNPRM will not present a 
significant economic burden to small entities. Therefore it is not 
necessary at this time to propose alternative rules. Notwithstanding 
our finding, we request comment on alternatives that might minimize the 
amount of adverse economic impact, if any, on small entities.

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

    21. None.
    22. Pursuant to sections 4(i), 301, 302, 303(e), 303(f), and 303(r) 
of the Communications Act of 1934, as amended, 47 U.S.C. Sections 
154(i), 301, 302, 303(e), 303(f), and 303(r), the Further Notice of 
Proposed Rule Making is hereby Adopted.

List of Subjects in 47 CFR Part 15

    Communications equipment.

Federal Communications Commission.
Magalie Roman Salas,
Secretary.

Proposed Rule Changes

    For the reasons discussed in the preamble, the Federal 
Communications Commission proposes to amend 47 CFR Part 15 as follows:

PART 15--RADIO FREQUENCY DEVICES

    1. The authority citation for part 15 continues to read as follows:

    Authority: 47 U.S.C. 154, 302, 303, 304, 307, 336 and 544A.
    2. Amend Sec. 15.247 as follows:
    a. Revise paragraphs (a) introductory text, (a)(1)(ii), 
(a)(1)(iii), (a)(2), (b)(1), (c) and (d).
    b. Redesignate paragraphs (b)(3) and (b)(4) as paragraphs (b)(4) 
and (b)(5).
    c. Add a new paragraph (b)(3), and revise new paragraphs (b)(4) and 
(b)(5).
    d. Remove paragraph (e).
    e. Redesignate paragraphs (f), (g), and (h) as paragraphs (e), (f), 
and (g).
    f. Revise new paragraphs (e), (f), and (g) (The Note following 
redesignated paragraph (g) is unchanged.).
    The additions and revisions read as follows:


Sec. 15.247  Operation within the bands 902-928 MHz, 2400-2483.5 MHz, 
and 5725-5850 MHz.

    (a) Operation under the provisions of this section is limited to 
frequency hopping and direct sequence spread spectrum systems and 
digitally modulated intentional radiators that comply with the 
following provisions:
    (1) * * *
    (ii) Frequency hopping systems operating in the 5725-5850 MHz band 
shall use at least 75 hopping frequencies. The maximum 20 dB bandwidth 
of the hopping channel is 1 MHz. The average time of occupancy on any 
frequency shall not be greater than 0.4 seconds within a 30 second 
period.
    (iii) Frequency hopping systems in the 2400-2483.5 MHz band shall 
use at least 75 non-overlapping channels, except that as few as 15 non-
overlapping channels may be used for systems that intelligently modify 
their hopsets in accordance with paragraph (g) of this section. Hopsets 
modified in this manner must be re-determined at least once every 30 
seconds. The average time of occupancy on any channel shall not be 
greater than 0.4 seconds within a period of 0.4 seconds multiplied by 
the number of hopping channels employed.
    (2) Systems using direct sequence spread spectrum and digital 
modulation techniques may operate in the 902-928 MHz, 2400-2483.5 MHz, 
and 5725-5850 MHz bands.
    (b) * * *
    (1) For frequency hopping systems in the 2400-2483.5 MHz band 
employing at least 75 hopping channels, and all frequency hopping 
systems in the 5725-5850 MHz band: 1 Watt. For all other frequency 
hopping systems in the 2400-2483.5 band: 0.125 Watt
* * * * *
    (3) For systems using digital modulation in the 902-928 MHz, 2400-
2483.5 MHz, and 5725-5780 MHz bands: 1 Watt.
    (4) Except as shown below in this paragraph (b)(4), if transmitting 
antennas of directional gain greater than 6 dBi are used, the peak 
output power from the intentional radiator shall be reduced below the 
stated values in paragraph (b)(3) by the amount in dB that the 
directional gain of the antenna exceeds 6 dBi.
    (i) Systems operating in the 2400-2483.5 MHz band that are used 
exclusively for fixed, point-to-point operations may employ 
transmitting antennas with directional gain greater than 6 dBi provided 
the maximum peak output power of the intentional radiator is reduced by 
1 dB for every 3 dB that the directional gain of the antenna exceeds 6 
dBi.
    (ii) Systems operating in the 5725-5850 MHz band that are used 
exclusively for fixed, point-to-point operations may employ 
transmitting antennas with directional gain greater than 6 dBi without 
any corresponding reduction in transmitter peak output power.
    (iii) Fixed, point-to-point operation, as used in paragraphs 
(b)(4)(i) and (b)(4)(ii) of this section, excludes the use of point-to-
multipoint systems, omnidirectional applications, and multiple co-
located intentional radiators transmitting the same information. The 
operator of the spread spectrum intentional radiator or, if the 
equipment is professionally installed, the installer is responsible for 
ensuring that the system is used exclusively for fixed, point-to-point 
operations. The instruction manual furnished with the intentional 
radiator shall contain language in the installation instructions 
informing the operator and the installer of this responsibility.
    (5) Systems operating under the provisions of this section shall be 
operated in a manner that ensures that the public is not exposed to 
radio frequency energy levels in excess of the Commission's guidelines. 
See Sec. 1.1307(b)(1) of this chapter.
    (c) In any 100 kHz bandwidth outside the frequency band in which 
the spread spectrum or digitally modulated intentional radiator is 
operating, the radio frequency power than is produced by the 
intentional radiator shall be at least 20 dB below that in the 100 kHz 
bandwidth within the band that contains the highest level of the 
desired power, based on either an RF conducted or a radiated 
measurement. Attenuation below the general limits specified in 
Sec. 15.209(a) is not required. In addition, radiated emissions which 
fall in the restricted bands, as defined in Sec. 15.205(a), must also 
comply with the radiated emission limits specified in Sec. 15.209(a) 
(see Sec. 15.205(c)).
    (d) For direct sequence spread spectrum and digitally modulated 
systems, the peak power spectral density conducted from the intentional 
radiator to the antenna shall not be greater than 8 dBm in any 3 kHz 
band during any time interval of continuous transmission.
    (e) For the purposes of this section, hybrid systems are those that 
employ a combination of both frequency hopping and direct sequence or 
digital modulation techniques. The frequency hopping operation of the 
hybrid system, with the direct sequence or digital modulation operation 
turned off, shall have an average time of occupancy on any frequency 
not to exceed 0.4 seconds within a time period in seconds equal to the 
number of hopping frequencies employed multiplied by 0.4. The direct 
sequence or the digital modulation

[[Page 31589]]

operation of the hybrid system, with the frequency hopping operation 
turned off, shall comply with the power density requirements of 
paragraph (d) of this section.
    (f) Frequency hopping systems are not required to employ all 
available hopping channels during each transmission. However, the 
system, consisting of both the transmitter and the receiver, must be 
designed to comply with all of the regulations in this section should 
the transmitter be presented with a continuous data (or information) 
stream. In addition, a system employing short transmission bursts must 
comply with the definition of a frequency hopping system and must 
distribute its transmissions over the minimum number of hopping 
channels specified in this section.
    (g) The incorporation of intelligence within a frequency hopping 
system that permits the system to recognize other users within the 
spectrum band so that it individually and independently chooses and 
adapts its hopsets to avoid hopping on occupied channels is permitted. 
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.
* * * * *
[FR Doc. 01-14526 Filed 6-11-01; 8:45 am]
BILLING CODE 6712-01-U


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