[Federal Register Volume 61, Number 67 (Friday, April 5, 1996)]
[Proposed Rules]
[Pages 15206-15208]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 96-8386]
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FEDERAL COMMUNICATIONS COMMISSION
47 CFR Parts 2 and 15
[ET Docket No. 96-8; FCC 96-36]
Spread Spectrum Transmitters
AGENCY: Federal Communications Commission.
ACTION: Proposed rule.
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SUMMARY: By this Notice of Proposed Rule Making (``NPRM''), the
Commission proposes to amend its rules regarding the operation of
spread spectrum transmission systems in the 902-928 MHz, 2400-2483.5
MHz and 5725-5850 MHz bands. For simplicity, these bands will be
referenced in this proposal as 915 MHz, 2450 MHz and 5800 MHz,
respectively. The Commission proposes to eliminate the limit on
directional gain antennas for spread spectrum transmitters operating in
the 5800 MHz band. We are also proposing to reduce, from 50 to 25, the
minimum number of channels required for frequency hopping spread
spectrum systems operating in the 915 MHZ band. These proposals are in
response to Petitions for Rule Making filed by Western Multiplex
Corporation (WMC) and Spectralink Corporation (Spectralink). We are
also denying a Petition for Rule Making from Symbol Technologies, Inc.
(Symbol). Further, the Commission on its own motion proposes a number
of amendments to the spread spectrum regulations to clarify the
existing regulations, to codify existing policies into the rules, and
to update the current definitions. These changes will expand the
ability of equipment manufacturers to develop spread spectrum systems
for unlicensed use.
DATES: Comments must be filed on or before June 19, 1996, and reply
comments must be filed on or before July 19, 1996.
[[Page 15207]]
ADDRESSES: Federal Communications Commission, 1919 M Street, N.W.,
Washington, D.C. 20554.
FOR FURTHER INFORMATION CONTACT: John Reed, Office of Engineering and
Technology, (202) 418-2455.
SUPPLEMENTARY INFORMATION: This is a summary of the Commission's Notice
of Proposed Rule Making, ET Docket No. 96-8, FCC 96-36, adopted January
30, 1996, and released February 5, 1996. The full text of this
Commission decision is available for inspection and copying during
normal business hours in the FCC Reference Center (Room 239), 1919 M
Street, N.W., Washington, D.C., and also may be purchased from the
Commission's duplication contractor, International Transcription
Service, (202) 857-3800, 2100 M Street, N.W., Suite 140, Washington
D.C. 20037.
Summary of Notice
1. The Commission is proposing to amend Parts 2 and 15 of the rules
regarding the operation of spread spectrum transmission systems in the
915 MHz, 2450 MHz and 5800 MHz bands. The spread spectrum rules, as
originally adopted, did not specify a limit on antenna gain. At that
time there were few other operators in these bands and little potential
that interference would be caused to other users. Further, we wished to
offer an incentive to spur the development of spread spectrum systems.
These bands, especially the 915 MHz and the 2450 MHz bands, are now
becoming more crowded, particularly with mobile units, increasing the
potential that spread spectrum systems using high gain antennas will
cause harmful interference. In addition to the licensed radio services,
wireless computer local area network systems and various consumer
products, such as cordless telephones, are being used under Part 15 in
the 915 MHz and 2450 MHz bands.
2. Since there are few operators in the 5800 MHz band, the
potential that harmful interference will occur from the use of
directional antennas is much lower. There are also fewer mobile users
in the 5800 MHz band. It is easier to engineer a fixed, point-to-point
system to operate without causing harmful interference problems if the
other stations in that band are fixed in location. Further, the 5800
MHz band is ideal for fixed, point-to-point wideband microwave
operations, the type of applications desired by WMC. Accordingly, the
Commission believes the limit on directional antenna gain should only
be eliminated for spread spectrum systems operating in the 5800 MHz
band. We request comment on this proposal. While we are not inclined to
provide a similar relaxation for the 2450 MHz band, we also ask for
comment on whether we should eliminate the 6 dB limit on directional
antenna gain in this band.
3. The Commission further believes that if spread spectrum
transmitters employing high gain antennas were made available to the
general public, it would be difficult to ensure that these systems are
used only for fixed, point-to-point applications. In addition, high
gain directional antenna systems, because of their narrow transmission
beamwidth and the problems associated with aligning the transmitter
with the receiver site, are not products that would normally be
employed by the general public. Accordingly, we believe that the
marketing of spread spectrum systems employing high gain antennas
should be limited to commercial or industrial operators and exclude
sales to the general public. The Commission further proposes to hold
the operator of a spread spectrum system responsible for ensuring that
the system is operated in a compliant manner. In addition, we propose
to require that the manual supplied with the spread spectrum
transmitter contain language in the installation instructions notifying
the operator of this responsibility.
4. In addition, absent controls regarding the locations and manner
in which spread spectrum transmitters may be used, systems employing
high gain directional antennas could expose the public to potentially
harmful signal levels that exceed the radio frequency exposure limits
in our rules and recommended by various standards-setting
organizations. In order to meet our obligation under the National
Environmental Policy Act, we propose to hold the holder of the grant of
certification for the transmitter, the grantee, responsible for
ensuring that the equipment is designed to minimize exposure of the
public to excessive radio frequency (RF) signal levels. Comments are
requested concerning possible biological hazards from the high
effective radiated power levels that could be emitted from these
systems, any additional methods that can be employed to prevent
unnecessary exposure of the public, and whether we should prescribe the
use of specific means for preventing such exposure.
5. The Commission also seeks comments in two additional areas
regarding the technical standards for spread spectrum transmission
systems operating without a limit on directional antenna gain. The
first of these concerns a reduction in the output power of the
transmitter based on the amount that the increase in directional
antenna gain exceeds the current limit of 6 dBi. We propose that the
output power of a transmitter would need to be decreased by 1 dB for
every 3 dB that the antenna gain exceeds 6 dBi in order to maintain an
``equivalent'' area of interference, i.e., the geographic area over
which interference could result with a directional antenna as compared
to the area obtained with an omnidirectional antenna. See the proposed
new Section 15.274(b)(4) in Appendix B of the NPRM. We are also seeking
comments on whether the rules should specify limits on the horizontal
and vertical beamwidths of antennas used with point-to-point systems.
Certain antenna designs, e.g., a horizontally polarized yagi antenna,
concentrate the signal strength in azimuth (horizontal) but not in
elevation (vertical). A fixed, point-to-point system employing an
antenna with a wide elevation beamwidth that is pointed towards an
office building with multiple floors could result in severe
interference problems to any party in that building who is in line with
the system and is operating in the same band. Several antenna designs
concentrate the radiated signals in both azimuth and elevation, e.g.,
circular dish antennas and stacked yagi antennas. The Commission
believes that any interference problems resulting from excessive
vertical emissions could be resolved if the 3 dB beamwidths, in both
the vertical and the horizontal planes, of the high gain directional
antennas employed with these fixed, point-to-point systems differ by no
more than a factor of two and are proposing such a limit.
6. As SpectraLink observes in its petition, there could be mutual
interference problems between wideband, multilateration LMS systems and
Part 15 frequency hopping spread spectrum systems, and it would be
beneficial if these two operations could avoid sharing the same
spectrum. The modification sought by SpectraLink would appear to
promote frequency sharing within this band. Therefore, the Commission
proposes to amend the rules to permit frequency hopping spread spectrum
systems in the 915 MHz band to use only 25 hopping channels, provided
that those systems employ hopping channel bandwidths of at least 250
kHz and the transmitters operate at a reduced power level. Hopping
systems using channel bandwidths less than 250 kHz already can avoid
operating in the bands used by broadband multilateration LMS systems
and require no decrease in the
[[Page 15208]]
minimum number of hopping channels. For frequency hopping systems
employing channel bandwidths of 250 kHz or greater, we propose to
reduce the minimum number of hopping channels to 25. Consistent with
this plan, we are also proposing to modify the maximum average time of
occupancy on any hopping frequency to 0.4 seconds in any 10 second
period to correspond to the reduction in the number of hopping
channels. Comments are also requested as to whether the rules should
specify a formula for the minimum number of hopping channels based on
the amount by which the bandwidth of the hopping channel exceeds 250
kHz.
7. Further, in order to reduce the potential for interference due
to the smaller number of hopping channels, we propose to require that
frequency hopping spread spectrum systems in the 915 MHz band that use
fewer than 50 hopping channels operate with a maximum peak transmitter
output power of 500 mW.
8. We are also denying the Petition for Rule Making from Symbol to
reduce the minimum number of hopping channels for frequency hopping
spread spectrum systems operating in the 2450 MHz or 5800 MHz bands.
9. There are also several additional regulations concerning Part 15
spread spectrum transmission systems that need to be clarified,
codified or amended. They are Spectral power density, Short duration
transmissions, Measurement of processing gain, Limits on unwanted
emissions, Frequency hopping coordination, External radio frequency
power amplifiers, Transition provisions, Definition of direct sequence
and Pseudorandom sequence and frequency hopping systems. These are
discussed in more detail in the full text of the Commission's NPRM, ET
Docket 96-8.
Initial Regulatory Flexibility Analysis
1. Reason for Action: This rule making proceeding is initiated to
obtain comment regarding proposed changes to the regulations for non-
licensed spread spectrum transmitters.
2. Objectives: The Commission seeks to determine if the standards
should be amended as sought in Petitions for Rule Making filed by WMC,
Symbol and SpectraLink. Additional amendments are also proposed to
clarify the existing regulations and to codify existing policies into
the rules.
3. 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.
4. Reporting, Recordkeeping and Other Compliance Requirements: Part
15 spread spectrum transmitters are already required to be authorized
under the Commission's certification procedure as a prerequisite to
marketing and importation. The changes proposed in this proceeding
would not change any of the current reporting or recordkeeping
requirements. Further, the proposed regulations add permissible methods
of operation and would not require the modification of any existing
products.
5. Federal Rules Which Overlap, Duplicate or Conflict With These
Rules: None.
6. Description, Potential Impact and Number of Small Entities
Involved: The actions proposed in this proceeding add permissible
methods of operation and will not require the modification of any
existing products. Accordingly, there should be no mandatory impact on
any small entities.
7. Any Significant Alternatives Minimizing the Impact on Small
Entities Consistent with Stated Objectives: None.
List of Subjects
47 CFR Part 2
Communications equipment, Radio.
47 CFR Part 15
Communications equipment, Radio.
Federal Commications Commission.
William F. Caton,
Acting Secretary.
[FR Doc. 96-8386 Filed 4-4-96; 8:45 am]
BILLING CODE 6712-01-P
