Ultra-Wideband Transmission Systems, 6771-6776 [05-2505]

Agencies

• FEDERAL COMMUNICATIONS COMMISSION

[Federal Register Volume 70, Number 26 (Wednesday, February 9, 2005)]
[Rules and Regulations]
[Pages 6771-6776]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: 05-2505]


-----------------------------------------------------------------------

FEDERAL COMMUNICATIONS COMMISSION

47 CFR Part 15

[ET Docket No. 98-153; FCC 04-285]


Ultra-Wideband Transmission Systems

AGENCY: Federal Communications Commission.

ACTION: Final rule.

-----------------------------------------------------------------------

SUMMARY: This document responds to two petitions for reconsideration 
that were filed in response to the Commission's decision to establish 
regulations for unlicensed ultra-wideband (``UWB'') operation. It also 
responds to the rule making proposals contained in the Memorandum 
Opinion and Order and Further Notice of Proposed Rule Making in this 
docket. The order establishes new rules for wideband unlicensed devices 
operating in the 5925-7250 MHz, 16.2-17.7 GHz, and 22.12-29 GHz bands.

DATES: Effective March 11, 2005.

FOR FURTHER INFORMATION CONTACT: John Reed (202) 418-2455, Policy and 
Rules Division, Office of Engineering and Technology.

SUPPLEMENTARY INFORMATION: This is a summary of the Second Report and 
Order and Second Memorandum Opinion and Order (``2nd R&O and 2nd 
MO&O''), FCC 04-285, adopted December 15, 2004, and released December 
16, 2004. 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 copy contractor, Best Copy and Printing, Inc. 445 12th 
Street, Room CY-B402, Washington, DC, (202) 488-5300; FAX (202) 488-
5563. The full text may also be downloaded at: www.fcc.gov. Alternative 
formats are available to persons with disabilities by contacting Brian 
Millin at (202) 418-7426 or TTY (202) 418-7365.

Summary of Second Report and Order

    1. On February 14, 2002, the Commission adopted a First Report and 
Order implementing regulations to permit the unlicensed operation of 
ultra-wideband transmission systems. In response to fourteen petitions 
for reconsideration, a Memorandum Opinion and Order and Further Notice 
of Proposed Rule Making (``MO&O and FNPRM'') was adopted on February 
13, 2003, 69 FR 19746 and 69 FR 19773, April 22, 2003. Specifically, 
the Commission proposed amendments to four areas of its part 15 
regulations. These amendments addressed: (1) The operation of low PRF 
systems in the 3.1-10.6 GHz band; (2) the measurement procedures 
applied to frequency hopping vehicular radar systems operating in the 
22-29 GHz band; (3) the peak power limits applicable to wide-bandwidth, 
non-UWB part 15 transmitters; and (4) the elimination of the UWB 
definition.
    2. Low PRF UWB systems. In the FNPRM, the Commission invited 
comment on whether to amend the rules to permit the operation of any 
UWB product under the UWB standards currently designated for hand-held 
devices as long as the PRF does not exceed 200 kHz and the equipment 
employs a pulsed or an impulse modulation. In the 2nd R&O, the 
Commission declines to amend its rules stating that low PRF systems can 
have a higher potential for causing interference unless some type of 
signal processing is incorporated in the victim receiver. The 
Commission will accommodate the requests from the equipment developers 
by increasing the peak power emission limit for select frequency bands 
available under the non-UWB part 15 regulations.
    3. Non-UWB peak power emission limits. When an average emission 
limit

[[Page 6772]]

is specified for non-UWB devices, the rules also specify a limit on 
peak power that is 20 dB greater than the average limit. In some cases, 
peak measurement by a spectrum analyzer requires the application of a 
pulse desensitization correction factor (``PDCF'') in order to 
compensate for the analyzer's inability to respond fast enough to 
measure the true peak for pulse widths narrower than the inverse of the 
resolution bandwidth. This peak limit may effectively prohibit some 
wideband operations. Further, a limit on the total peak power level is 
not well suited to measure the operation of, or represent the 
interference potential of, transmitters that employ extremely wide 
bandwidths. For that reason, the Commission proposed in the FNPRM to 
implement the same peak limit that is applied to UWB systems.
    4. The total peak power of such a wideband system is not relevant 
to the interference potential of the device. Rather, it is the 
potential power in the bandwidth of the victim receiver that is 
relevant. In the 2nd R&O, the Commission recognizes that allowing 
increased peak power levels could have an impact on some radio services 
and also expresses concerned that allowing higher peak power levels 
could result in a significant increase in the number of consumer 
products along with a corresponding increase in interference potential. 
Thus, it believes that cautious constraints on the permitted frequency 
bands of operation and the standards for operation within those bands 
are necessary while it gains experience.
    5. The Commission is amending its part 15 rules to permit higher 
peak emission levels in the 5925-7250 MHz band, indicating that the 
fixed, fixed-satellite, and mobile systems employed in this band likely 
incorporate a sufficient level of signal processing to reduce, if not 
eliminate, their vulnerability to increased peak emission levels, or it 
is expected that such authorized systems would generally be located in 
remote areas or with the receiving antennas situated in such a manner 
that they would not be routinely subject to emissions from nearby part 
15 devices. The Commission also is permitting higher peak emission 
levels in the 16.2-17.7 GHz band but will limit operation within this 
band to vehicular back-up assistance radars that operate only when the 
vehicle is in reverse. This will significantly limit the proliferation 
of such devices and should ensure that harmful interference does not 
occur to the authorized radio services. Potential equipment 
manufacturers are forewarned that the 17.3-17.7 GHz portion of the 
16.2-17.7 GHz band has been allocated in Region 2 and the United States 
for the Broadcast Satellite Service, effective April 1, 2007. Once this 
allocation becomes effective, there is a possibility that the 17.3-17.7 
GHz band may become designated as a restricted band and that part 15 
fundamental emissions will be prohibited in this portion of the 
spectrum.
    6. A peak EIRP limit of 20 log (RBW/50) dBm is adopted for the 
5925-7250 MHz and 16.2-17.7 GHz bands, with RBW, the resolution 
bandwidth of the measurement instrument, being 1 to 50 MHz. This peak 
limit applies to the 50 MHz band centered at the frequency at which the 
highest average emission level occurs. RBW must be no greater than the 
-10 dB bandwidth of the emission. If frequency hopping or stepped 
frequency modulation is employed, the frequency hop or step function 
shall be disabled and the transmitter shall operate continuously on a 
fundamental frequency to measure the -10 dB bandwidth that is used to 
determine the maximum RBW that may be employed for the peak emission 
level. For transmitters operating under these new peak limits, the 
Commission is adopting the more stringent UWB average emission 
specifications requested by the National Telecommunications and 
Information Administration (``NTIA''). These limits and other pertinent 
standards are shown in the accompanying changes to the rules.
    7. Vehicular radar systems. In the FNPRM, the Commission proposed 
to permit pulsed frequency hopping vehicular radars to be included 
under the definition of a UWB device provided the transmitters occupy 
the minimum required bandwidth within any 10 millisecond period rather 
than at any instantaneous point in time. However, the Commission is 
unwilling at this time to classify as a UWB device a frequency hopping 
transmitter that emits relatively narrowband signals. However, the 
systems can be accommodated under the non-UWB rules by increasing the 
peak power emission limit. As requested by NTIA, a frequency hopped 
vehicular radar system may not operate in the restricted bands. Thus, 
the frequency band of operation that is being established for this 
vehicle radar system is 23.12-29.0 GHz, exclusive of the restricted 
band at 23.6-24.0 GHz. Vehicular radar transmitters operating under 
these new peak limits also will be subject to limits similar to the UWB 
average emission specifications, as requested by NTIA. Any type of 
modulation may be employed. These limits and other pertinent standards 
are shown in the accompanying changes to the rules.
    8. The interference aspects of a transmitter employing frequency 
hopping, stepped frequency modulation or gating are quite similar, as 
viewed by a receiver, in that both appear to the receiver to emit for a 
short period of time followed by a quiet period. Permitting the 
emissions from frequency hopping systems to be measured with the 
hopping active could give such systems a competitive advantage by 
permitting higher instantaneous average power levels than what are 
allowed for gated systems. Thus, the Commission also is eliminating the 
requirement that gated or stepped systems operating under this new 
regulation be tested with the gating or step function turned off. 
However, no provision is provided to permit transmitters employing 
swept frequency modulation to perform measurements with the sweep 
stopped. The Commission also is adopting NTIA's requested measurement 
procedure requiring that the RMS average and peak emission measurements 
be repeated with the analyzer in the maximum hold mode until there is 
no significant increase, i.e., less than 3 dB, in any of the maximum 
hold values.
    9. The UWB regulations for operation in the 22-29 GHz band require 
vehicular radar systems that employ gating to be measured with the 
transmitter gated on and should be subject to the same measurement 
procedures. Thus, the Commission is amending the UWB regulations to 
permit the emissions from gated vehicular radar systems to be measured 
with the gating active. However, as requested by NTIA similar 
provisions are not being applied to UWB systems that employ frequency 
hopping, stepped frequency or similar modulation techniques.
    10. Clarification of existing non-UWB peak power emission limits. 
As proposed in the FNPRM, the Commission is amending 47 CFR 15.35(b) to 
clarify that the peak power requirement applies to the total peak power 
produced by the device, unless specifically stated otherwise, and may 
necessitate the use of a PDCF. This clarification does not result in 
any changes to the current part 15 standards and should eliminate any 
confusion on the need to apply a PDCF under certain modulation and 
measurement conditions.
    11. UWB definition. In the FNPRM, the Commission proposed to 
eliminate the minimum bandwidth requirement and to permit the operation 
of any transmission system, regardless of its

[[Page 6773]]

bandwidth, as long as it complies with the standards for UWB operation 
set forth in Subpart F of 47 CFR part 15. However, the Commission has 
accommodated the narrowband operations sought by the proponents in this 
proceeding through its amendments to the peak power levels while 
keeping any further expansion of equipment applications out of the 
sensitive restricted bands. Because of these changes, there is no 
necessity at this time to eliminate the UWB minimum bandwidth 
requirements. Such changes could be disruptive and could further delay 
the introduction of UWB devices.

Summary of Second Memorandum Opinion and Order

    12. The 2nd MO&O addresses two petitions for reconsideration that 
were filed in response to the Memorandum Opinion and Order and Further 
Notice of Proposed Rule Making. Cingular, Inc. objected to the presence 
and level of emissions from UWB devices that may appear in the 
frequency bands allocated for the Cellular Radiotelephone Service 
(``cellular'') and for the Personal Communications Services (``PCS''); 
claimed that the Commission can not legally permit the unlicensed 
operation of radio frequency (``RF'') devices except as specifically 
authorized by Congress under 47 U.S.C. 307(e); and claimed that 
cellular and PCS licensees have exclusive use of the spectrum assigned 
to their respective operations and that any emissions from UWB devices 
undermine this exclusivity. The issues raised by Cingular are dismissed 
or denied, as appropriate. The Satellite Industry Association (``SIA'') 
argued that the UWB emission limits in the 3650-4200 MHz band used by 
C-band fixed satellite systems (``FSS'') are excessive and will result 
in harmful interference. The SIA petition is denied.

Administrative Provisions

    13. The Commission will send a copy of this Second Report & Order 
and Second Memorandum Opinion and Order in a report to be sent to 
Congress and the General Accounting Office pursuant to the 
Congressional Review Act, see 5 U.S.C. 801(a)(1)(A).
    14. Final Regulatory Flexibility Certification. The Regulatory 
Flexibility Act of 1980, as amended (RFA),\1\ requires that a 
regulatory flexibility analysis be prepared for notice-and-comment rule 
making proceedings, unless the agency certifies that ``the rule will 
not, if promulgated, have a significant economic impact on a 
substantial number of small entities.'' \2\ The RFA generally defines 
the term ``small entity'' as having the same meaning as the terms 
``small business,'' ``small organization,'' and ``small governmental 
jurisdiction.'' \3\ In addition, the term ``small business'' has the 
same meaning as the term ``small business concern'' under the Small 
Business Act.\4\ A ``small business concern'' is one which: (1) Is 
independently owned and operated; (2) is not dominant in its field of 
operation; and (3) satisfies any additional criteria established by the 
Small Business Administration (SBA).\5\
---------------------------------------------------------------------------

    \1\ The RFA, see 5 U.S.C. 601-612, has been amended by the Small 
Business Regulatory Enforcement Fairness Act of 1996 (SBREFA), 
Public Law 104-121, Title II, 110 Stat. 857 (1996).
    \2\ 5 U.S.C. 605(b).
    \3\ 5 U.S.C. 601(6).
    \4\ 5 U.S.C. 601(3) (incorporating by reference the definition 
of ``small-business concern'' in the Small Business Act, 15 U.S.C. 
632). Pursuant to 5 U.S.C. 601(3), the statutory definition of a 
small business applies ``unless an agency, after consultation with 
the Office of Advocacy of the Small Business Administration and 
after opportunity for public comment, establishes one or more 
definitions of such term which are appropriate to the activities of 
the agency and publishes such definition(s) in the Federal 
Register.''
    \5\ 15 U.S.C. 632.
---------------------------------------------------------------------------

    15. In this Second Report and Order and Second Memorandum Opinion 
and Order, we are implementing a change to the rules to facilitate the 
operation of wideband unlicensed transmitters. We also are responding 
to two petitions for reconsideration regarding rules that permit the 
marketing and operation of products incorporating ultra-wideband 
(``UWB'') technology. UWB devices operate by employing very narrow or 
short duration pulses that result in very large or wideband 
transmission bandwidths. With appropriate technical standards, UWB 
devices can operate on spectrum occupied by existing radio services 
without causing interference, thereby permitting scarce spectrum 
resources to be used more efficiently. Further, as noted in the text we 
have continued to apply conservative limits to the standards applicable 
for UWB operation, until such time as we gain additional experience, to 
ensure that harmful interference would not be caused to other radio 
spectrum users. Further, the changes adopted in this proceeding will 
not affect any party legally manufacturing or marketing UWB devices. 
Thus, we expect that our actions do not amount to a significant 
economic impact. Accordingly, we certify that the rules being adopted 
in this Memorandum Opinion and Order will not have a significant 
economic impact on a substantial number of small entities.
    16. The Commission will send a copy of the Second Report and Order 
and Second Memorandum Opinion and Order, including a copy of this Final 
Regulatory Flexibility Certification, in a report to Congress pursuant 
to the Congressional Review Act.\6\ In addition, the Second Report and 
Order and Second Memorandum Opinion and Order and this final 
certification will be sent to the Chief Counsel for Advocacy of the 
SBA, and will be published in the Federal Register.\7\
---------------------------------------------------------------------------

    \6\ See 5 U.S.C. 801(a)(1)(A).
    \7\ See 5 U.S.C. 605(b).
---------------------------------------------------------------------------

    17. Ordering Clauses. This action is taken pursuant to Sections 
4(i), 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), 302, 303(e), 
303(f), 303(r), 304 and 307. It also is ordered that part 15 of the 
Commission's Rules and Regulations is amended as specified in rule 
changes, effective 30 days after publication in the Federal Register. 
It is ordered that the Petition for Reconsideration from Cingular, 
Inc., is denied. It is ordered that the Petition for Reconsideration 
from Satellite Industry Association is dismissed.
    18. The Commission's Consumer and Governmental Affairs Bureau, 
Reference Information Center, shall send a copy of this Second Report 
and Order and Second Memorandum Opinion and Order, including the Final 
Regulatory Flexibility Certification, to the Chief Counsel for Advocacy 
of the Small Business Administration.
    19. It is further ordered that this proceeding is terminated.

List of Subjects 47 CFR Part 15

    Communications equipment, Radio, Reporting and recordkeeping 
requirements, Security measures.

Federal Communications Commission.
William F. Caton,
Deputy Secretary.

Rule Changes

0
For the reasons discussed in the preamble, title 47 of the Code of 
Federal Regulations, part 15, is amended as follows:

PART 15--RADIO FREQUENCY DEVICES

0
1. The authority citation for part 15 continues to read as follows:

    Authority: 47 U.S.C. 154, 302a, 303, 304, 307, 336 and 544a.

0
2. Section 15.35 is amended by revising paragraph (b) to read as 
follows:


Sec.  15.35  Measurement detector functions and bandwidths.

* * * * *

[[Page 6774]]

    (b) Unless otherwise specified, on any frequency or frequencies 
above 1000 MHz, the radiated emission limits are based on the use of 
measurement instrumentation employing an average detector function. 
Unless otherwise specified, measurements above 1000 MHz shall be 
performed using a minimum resolution bandwidth of 1 MHz. When average 
radiated emission measurements are specified in this part, including 
average emission measurements below 1000 MHz, there also is a limit on 
the peak level of the radio frequency emissions. Unless otherwise 
specified, e.g., see Sec. Sec.  15.250, 15.252, 15.255, and 15.509-
15.519, the limit on peak radio frequency emissions is 20 dB above the 
maximum permitted average emission limit applicable to the equipment 
under test. This peak limit applies to the total peak emission level 
radiated by the device, e.g., the total peak power level. Note that the 
use of a pulse desensitization correction factor may be needed to 
determine the total peak emission level. The instruction manual or 
application note for the measurement instrument should be consulted for 
determining pulse desensitization factors, as necessary.
* * * * *

0
3. Section 15.215 is amended by revising paragraph (c), to read as 
follows:


Sec.  15.215  Additional provisions to the general radiated emission 
limitations.

* * * * *
    (c) Intentional radiators operating under the alternative 
provisions to the general emission limits, as contained in Sec. Sec.  
15.217 through 15.257 and in Subpart E of this part, must be designed 
to ensure that the 20 dB bandwidth of the emission, or whatever 
bandwidth may otherwise be specified in the specific rule section under 
which the equipment operates, is contained within the frequency band 
designated in the rule section under which the equipment is operated. 
The requirement to contain the designated bandwidth of the emission 
within the specified frequency band includes the effects from frequency 
sweeping, frequency hopping and other modulation techniques that may be 
employed as well as the frequency stability of the transmitter over 
expected variations in temperature and supply voltage. If a frequency 
stability is not specified in the regulations, it is recommended that 
the fundamental emission be kept within at least the central 80% of the 
permitted band in order to minimize the possibility of out-of-band 
operation.

0
4. Section 15.250 is added to read as follows:


Sec.  15.250  Operation of wideband systems within the band 5925-7250 
MHz.

    (a) The -10 dB bandwidth of a device operating under the provisions 
of this section must be contained within the 5925-7250 MHz band under 
all conditions of operation including the effects from stepped 
frequency, frequency hopping or other modulation techniques that may be 
employed as well as the frequency stability of the transmitter over 
expected variations in temperature and supply voltage.
    (b) The -10 dB bandwidth of the fundamental emission shall be at 
least 50 MHz. For transmitters that employ frequency hopping, stepped 
frequency or similar modulation types, measurement of the -10 dB 
minimum bandwidth specified in this paragraph shall be made with the 
frequency hop or step function disabled and with the transmitter 
operating continuously at a fundamental frequency following the 
provisions of Sec.  15.31(m).
    (c) Operation on board an aircraft or a satellite is prohibited. 
Devices operating under this section may not be employed for the 
operation of toys. Except for operation onboard a ship or a terrestrial 
transportation vehicle, the use of a fixed outdoor infrastructure is 
prohibited. A fixed infrastructure includes antennas mounted on outdoor 
structures, e.g., antennas mounted on the outside of a building or on a 
telephone pole.
    (d) Emissions from a transmitter operating under this section shall 
not exceed the following equivalent isotropically radiated power (EIRP) 
density levels:
    (1) The radiated emissions above 960 MHz from a device operating 
under the provisions of this section shall not exceed the following RMS 
average limits based on measurements using a 1 MHz resolution 
bandwidth:

------------------------------------------------------------------------
                                                                EIRP in
                       Frequency in MHz                           dBm
------------------------------------------------------------------------
960-1610.....................................................      -75.3
1610-1990....................................................      -63.3
1990-3100....................................................      -61.3
3100-5925....................................................      -51.3
5925-7250....................................................      -41.3
7250-10600...................................................      -51.3
Above 10600..................................................      -61.3
------------------------------------------------------------------------

    (2) In addition to the radiated emission limits specified in the 
table in paragraph (d)(1) of this section, transmitters operating under 
the provisions of this section shall not exceed the following RMS 
average limits when measured using a resolution bandwidth of no less 
than 1 kHz:

------------------------------------------------------------------------
                                                                EIRP in
                       Frequency in MHz                           dBm
------------------------------------------------------------------------
1164-1240....................................................      -85.3
1559-1610....................................................      -85.3
------------------------------------------------------------------------

    (3) There is a limit on the peak level of the emissions contained 
within a 50 MHz bandwidth centered on the frequency at which the 
highest radiated emission occurs and this 50 MHz bandwidth must be 
contained within the 5925-7250 MHz band. The peak EIRP limit is 20 log 
(RBW/50) dBm where RBW is the resolution bandwidth in megahertz that is 
employed by the measurement instrument. RBW shall not be lower than 1 
MHz or greater than 50 MHz. The video bandwidth of the measurement 
instrument shall not be less than RBW. If RBW is greater than 3 MHz, 
the application for certification filed with the Commission shall 
contain a detailed description of the test procedure, calibration of 
the test setup, and the instrumentation employed in the testing.
    (4) Radiated emissions at or below 960 MHz shall not exceed the 
emission levels in Sec.  15.209.
    (5) Emissions from digital circuitry used to enable the operation 
of the transmitter may comply with the limits in Sec.  15.209 provided 
it can be clearly demonstrated that those emissions are due solely to 
emissions from digital circuitry contained within the transmitter and 
the emissions are not intended to be radiated from the transmitter's 
antenna. Emissions from associated digital devices, as defined in Sec.  
15.3(k), e.g., emissions from digital circuitry used to control 
additional functions or capabilities other than the operation of the 
transmitter, are subject to the limits contained in subpart B of this 
part. Emissisons from these digital circuits shall not be employed in 
determining the -10 dB bandwidth of the fundamental emission or the 
frequency at which the highest emission level occurs.
    (e) Measurement procedures:
    (1) All emissions at and below 960 MHz are based on measurements 
employing a CISPR quasi-peak detector. Unless otherwise specified, all 
RMS average emission levels specified in this section are to be 
measured utilizing a 1 MHz resolution bandwidth with a one millisecond 
dwell over each 1 MHz segment. The frequency span of the analyzer 
should equal the number of sampling bins times 1 MHz and the sweep rate 
of the analyzer should equal the number of sampling bins times one 
millisecond. The provision in Sec.  15.35(c) that allows emissions to 
be averaged over a 100 millisecond period does not

[[Page 6775]]

apply to devices operating under this section. The video bandwidth of 
the measurement instrument shall not be less than the resolution 
bandwidth and trace averaging shall not be employed. The RMS average 
emission measurement is to be repeated over multiple sweeps with the 
analyzer set for maximum hold until the amplitude stabilizes.
    (2) The peak emission measurement is to be repeated over multiple 
sweeps with the analyzer set for maximum hold until the amplitude 
stabilizes.
    (3) For transmitters that employ frequency hopping, stepped 
frequency or similar modulation types, the peak emission level 
measurement, the measurement of the RMS average emission levels, and 
the measurement to determine the frequency at which the highest level 
emission occurs shall be made with the frequency hop or step function 
active. Gated signals may be measured with the gating active. The 
provisions of Sec.  15.31(c) continue to apply to transmitters that 
employ swept frequency modulation.
    (4) The -10 dB bandwidth is based on measurement using a peak 
detector, a 1 MHz resolution bandwidth, and a video bandwidth greater 
than or equal to the resolution bandwidth.
    (5) Alternative measurement procedures may be considered by the 
Commission.

0
5. Section 15.252 is added to read as follows:


Sec.  15.252  Operation of wideband vehicular radar systems within the 
bands 16.2-17.7 GHz and 23.12-29.0 GHz.

    (a) Operation under this section is limited to field disturbance 
sensors that are mounted in terrestrial transportation vehicles. 
Terrestrial use is limited to earth surface-based, non-aviation 
applications. Operation within the 16.2-17.7 GHz band is limited to 
field disturbance sensors that are used only for back-up assistance and 
that operate only when the vehicle is engaged in reverse.
    (1) The -10 dB bandwidth of the fundamental emission shall be 
located within the 16.2-17.7 GHz band or within the 23.12-29.0 GHz 
band, exclusive of the 23.6-24.0 GHz restricted band, as appropriate, 
under all conditions of operation including the effects from stepped 
frequency, frequency hopping or other modulation techniques that may be 
employed as well as the frequency stability of the transmitter over 
expected variations in temperature and supply voltage.
    (2) The -10 dB bandwidth of the fundamental emission shall be 10 
MHz or greater. For transmitters that employ frequency hopping, stepped 
frequency or similar modulation types, measurement of the -10 dB 
minimum bandwidth specified in this paragraph shall be made with the 
frequency hop or step function disabled and with the transmitter 
operating continuously at a fundamental frequency following the 
provisions of Sec.  15.31(m).
    (3) For systems operating in the 23.12-29.0 GHz band, the 
frequencies at which the highest average emission level and at which 
the highest peak level emission appear shall be greater than 24.075 
GHz.
    (4) These devices shall operate only when the vehicle is operating, 
e.g., the engine is running. Operation shall occur only upon specific 
activation, such as upon starting the vehicle, changing gears, or 
engaging a turn signal. The operation of these devices shall be related 
to the proper functioning of the transportation vehicle, e.g., 
collision avoidance.
    (b) Emissions from a transmitter operating under this section shall 
not exceed the following equivalent isotropically radiated power (EIRP) 
density levels:
    (1) For transmitters operating in the 16.2-17.7 GHz band, the RMS 
average radiated emissions above 960 MHz from a device operating under 
the provisions of this section shall not exceed the following EIRP 
limits based on measurements using a 1 MHz resolution bandwidth:

------------------------------------------------------------------------
                                                                EIRP in
                       Frequency in MHz                           dBm
------------------------------------------------------------------------
960-1610.....................................................      -75.3
1610-16,200..................................................      -61.3
16,200-17,700................................................      -41.3
Above 17,700.................................................      -61.3
------------------------------------------------------------------------

    (2) For transmitters operating in the 23.12-29.0 GHz band, the RMS 
average radiated emissions above 960 MHz from a device operating under 
the provisions of this section shall not exceed the following EIRP 
limits based on measurements using a 1 MHz resolution bandwidth:

------------------------------------------------------------------------
                                                                EIRP in
                       Frequency in MHz                           dBm
------------------------------------------------------------------------
960-1610.....................................................      -75.3
1610-23,120..................................................      -61.3
23,120-23,600................................................      -41.3
23,600-24,000................................................      -61.3
24,000-29,000................................................      -41.3
Above 29,000.................................................     --61.3
------------------------------------------------------------------------

    (3) In addition to the radiated emission limits specified in the 
tables in paragraphs (b)(1) and (b)(2) of this section, transmitters 
operating under the provisions of this section shall not exceed the 
following RMS average EIRP limits when measured using a resolution 
bandwidth of no less than 1 kHz:

------------------------------------------------------------------------
                                                                EIRP in
                       Frequency in MHz                           dBm
------------------------------------------------------------------------
1164-1240....................................................      -85.3
1559-1610....................................................      -85.3
------------------------------------------------------------------------

    (4) There is a limit on the peak level of the emissions contained 
within a 50 MHz bandwidth centered on the frequency at which the 
highest radiated emission occurs and this 50 MHz bandwidth must be 
contained within the 16.2-17.7 GHz band or the 24.05-29.0 GHz band, as 
appropriate. The peak EIRP limit is 20 log (RBW/50) dBm where RBW is 
the resolution bandwidth in MHz employed by the measurement instrument. 
RBW shall not be lower than 1 MHz or greater than 50 MHz. Further, RBW 
shall not be greater than the -10 dB bandwidth of the device under 
test. For transmitters that employ frequency hopping, stepped frequency 
or similar modulation types, measurement of the -10 dB minimum 
bandwidth specified in this paragraph shall be made with the frequency 
hop or step function disabled and with the transmitter operating 
continuously at a fundamental frequency. The video bandwidth of the 
measurement instrument shall not be less than RBW. The limit on peak 
emissions applies to the 50 MHz bandwidth centered on the frequency at 
which the highest level radiated emission occurs. If RBW is greater 
than 3 MHz, the application for certification shall contain a detailed 
description of the test procedure, the instrumentation employed in the 
testing, and the calibration of the test setup.
    (5) Radiated emissions at or below 960 MHz shall not exceed the 
emission levels in Sec.  15.209.
    (6) Emissions from digital circuitry used to enable the operation 
of the transmitter may comply with the limits in Sec.  15.209 provided 
it can be clearly demonstrated that those emissions are due solely to 
emissions from digital circuitry contained within the transmitter and 
the emissions are not intended to be radiated from the transmitter's 
antenna. Emissions from associated digital devices, as defined in Sec.  
15.3(k) , e.g., emissions from digital circuitry used to control 
additional functions or capabilities other than the operation of the 
transmitter, are subject to the limits contained in subpart B of this 
part. Emissions from these digital circuits shall not be employed in 
determining the -10 dB bandwidth of

[[Page 6776]]

the fundamental emission or the frequency at which the highest emission 
level occurs.
    (c) Measurement procedures:
    (1) All emissions at and below 960 MHz are based on measurements 
employing a CISPR quasi-peak detector. Unless otherwise specified, all 
RMS average emission levels specified in this section are to be 
measured utilizing a 1 MHz resolution bandwidth with a one millisecond 
dwell over each 1 MHz segment. The frequency span of the analyzer 
should equal the number of sampling bins times 1 MHz and the sweep rate 
of the analyzer should equal the number of sampling bins times one 
millisecond. The provision in Sec.  15.35(c) that allows emissions to 
be averaged over a 100 millisecond period does not apply to devices 
operating under this section. The video bandwidth of the measurement 
instrument shall not be less than the resolution bandwidth and trace 
averaging shall not be employed. The RMS average emission measurement 
is to be repeated over multiple sweeps with the analyzer set for 
maximum hold until the amplitude stabilizes.
    (2) The peak emission measurement is to be repeated over multiple 
sweeps with the analyzer set for maximum hold until the amplitude 
stabilizes.
    (3) For transmitters that employ frequency hopping, stepped 
frequency or similar modulation types, the peak emission level 
measurement, the measurement of the RMS average emission levels, the 
measurement to determine the center frequency, and the measurement to 
determine the frequency at which the highest level emission occurs 
shall be made with the frequency hop or step function active. Gated 
signals may be measured with the gating active. The provisions of Sec.  
15.31(c) continue to apply to transmitters that employ swept frequency 
modulation.
    (4) The -10 dB bandwidth is based on measurement using a peak 
detector, a 1 MHz resolution bandwidth, and a video bandwidth greater 
than or equal to the resolution bandwidth.
    (5) Alternative measurement procedures may be considered by the 
Commission.

0
6. Section 15.515 is amended by adding a new paragraph (g) to read as 
follows:


Sec.  15.515  Technical requirements for vehicular radar systems.

* * * * *
    (g) The emission levels from devices operating under the provisions 
of this section that employ gated transmissions may be measured with 
the gating active. Measurements made in this manner shall be repeated 
over multiple sweeps with the analyzer set for maximum hold until the 
amplitude stabilizes.
0
7. Section 15.521 is amended by revising paragraph (d) to read as 
follows:


Sec.  15.521  Technical requirements applicable to all UWB devices.

* * * * *
    (d) Within the tables in Sec. Sec.  15.509, 15.511, 15.513, 15.515, 
15.517, and 15.519, the tighter emission limit applies at the band 
edges. Radiated emission levels at and below 960 MHz are based on 
measurements employing a CISPR quasi-peak detector. Radiated emission 
levels above 960 MHz are based on RMS average measurements over a 1 MHz 
resolution bandwidth. The RMS average measurement is based on the use 
of a spectrum analyzer with a resolution bandwidth of 1 MHz, an RMS 
detector, and a 1 millisecond or less averaging time. Unless otherwise 
stated, if pulse gating is employed where the transmitter is quiescent 
for intervals that are long compared to the nominal pulse repetition 
interval, measurements shall be made with the pulse train gated on. 
Alternative measurement procedures may be considered by the Commission.
* * * * *
[FR Doc. 05-2505 Filed 2-8-05; 8:45 am]
BILLING CODE 6712-01-P