**Before the**

**FEDERAL COMMUNICATIONS COMMISSION**

**Washington, DC 20554**

+-----------------------------------+---+------------------------------+
| In the Matter of                  | ) | ET Docket No. 03-122         |
|                                   |   |                              |
| Revision of Parts 2 and 15 of the | ) | RM - 10371                   |
| Commission's Rules to Permit      |   |                              |
| Unlicensed National Information   | ) |                              |
| Infrastructure (U‑NII) Devices in |   |                              |
| the 5 GHz Band                    | ) |                              |
|                                   |   |                              |
|                                   | ) |                              |
|                                   |   |                              |
|                                   | ) |                              |
|                                   |   |                              |
|                                   | ) |                              |
+-----------------------------------+---+------------------------------+

**[COMMENTS OF THE NATIONAL TELECOMMUNICATIONS]{.underline}**

**[AND INFORMATION ADMINISTRATION]{.underline}**

Michael D. Gallagher Kathy D. Smith

Acting Assistant Secretary for Chief Counsel

Communications and Information

Fredrick R. Wentland

Associate Administrator

Office of Spectrum Management

Charles T. Glass

Telecommunications Specialist

Office of Spectrum Management

Edward F. Drocella

Robert L. Sole

Electronics Engineers

Office of Spectrum Management National Telecommunications and

Information Administration

U.S. Department of Commerce

Room 4713

1401 Constitution Avenue, N.W.

Washington, DC 20230

\(202\) 482-1816

October 1, 2003

**TABLE OF CONTENTS**

**[Section]{.underline}** **[Page]{.underline}**

EXECUTIVE SUMMARY . . . . . . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . iv

I.  INTRODUCTION . . . . . . . . . . . . . . . . . . . . . . . . . . . .
    . . . . . . . . . . . . . . . . . 2

II. NTIA SUPPORTS THE COMMISSION'S PROPOSAL TO CHANGE

> THE U.S. TABLE OF FREQUENCY ALLOCATIONS TO
>
> ACCOMMODATE THE NEEDS OF FEDERAL AND NON-FEDERAL
>
> GOVERNMENT RADIO SERVICES OPERATNG IN THE 5 GHZ
>
> FREQUENCY RANGE. . . . . . . . . . . . . . . . . . . . . . . . . . . .
> . . . . . . . . . . . . . . . 3

III. NTIA SUPPORTS THE COMMISSION'S PROPOSAL TO MODIFY

> THE PART 15 RULES TO ACCOMMODATE EXPANDED USE OF
>
> U-NII DEVICES. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
> . . . . . . . . . . . . . . . . . . . 7

IV. NTIA SUPPORTS THE COMMISSION'S PROPOSAL TO REQUIRE

> U-NII DEVICES OPERATING IN THE 5.25-5.35 GHZ AND
>
> 5.47-5.725 GHZ FREQUENCY BANDS TO EMPLOY DFS TO AVOID
>
> INTERFERING WITH CRITICAL FEDERAL RADAR OPERATIONS . . . 7

V.  NTIA IS LEADING A PROJECT TEAM WITH GOVERNMENT

> AND INDUSTRY REPRESENTATIVES TO DEVELOP COMPLIANCE
>
> MEASUREMENT PROCEDURES FOR DFS ENABLED U-NII
>
> DEVICES. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
> . . . . . . . . . . . . . . . . . . . . .9

VI. NTIA SUPPORTS IMPLEMENTING TPC IN BOTH THE 5.25-5.35 GHZ

> AND 5.47-5.725 GHZ FREQUENCY BANDS . . . . . . . . . . . . . . . . . .
> . . . . 11

VII. NTIA RECOMMENDS THAT U-NII DEVICES OPERATING IN

> THE 5.25-5.35 GHZ FREQUENCY BAND THAT ARE
>
> IMPORTED SHOULD ADHERE TO THE COMMISSION'S
>
> PROPOSED TRANSITION SCHEDULE FOR DOMESTIC DEVICES . 13

VIII. IN ORDER TO AVOID CONFUSION, NTIA RECOMMENDS

> THAT ADDITIONAL DEFINITIONS BE INCLUDED IN THE
>
> COMMISSION'S RULES FOR U-NII DEVICES . . . . . . . . . . . . . . . . .
> . 13
>
> IX\. CONCLUSION . . . . . . . . . . . . . . . . . . . . . . . . . . .
> . . . . . . . . . . . . . . . . . . . 15
>
> DESCRIPTION OF RADAR USAGE IN THE 5 GHZ FREQUENCY
>
> RANGE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
> . . . . . . . . . . . . . . . . APPENDIX A
>
> DRAFT MEASUREMENT PROCEDURES FOR DFS EQUIPPED
>
> U-NII DEVICES. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
> . . . . . . . . . . . . . . . APPENDIX B
>
> SCHEDULE OF PROJECTED MILESTONES FOR 5 GHZ PROJECT
>
> TEAM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
> . . . . . . . . . . . . . . . . . . APPENDIX C

**EXECUTIVE SUMMARY**

The National Telecommunications and Information Administration (NTIA)
commends the Federal Communications Commission (Commission) for
initiating this proceeding to expand the options for unlicensed device
use, and particularly, linking such expanded use to adoption of new
technologies for active interference-avoidance. NTIA agrees with the
Commission regarding the significant benefits to the economy,
businesses, consumers, and government agencies that could be gained by
allowing unlicensed devices to operate in the 5.47-5.725 GHz frequency
range, provided that such operation is tied to effective implementation
of active interference-avoidance techniques. NTIA would also like to
commend the Commission for its careful consideration and review of
existing Part 15 Rules in the 5.25-5.35 GHz band as well as
consideration of the federal government and private sector spectrum
requirements in the 5 GHz frequency range. NTIA provides the following
comments to specific issues raised in the Unlicensed-National
Information Infrastructure (U-NII) Notice of Proposed Rulemaking (NPRM)
that may have an impact on critical federal systems used for scientific
research, aviation, and national defense.

NTIA supports the Commission's proposals to upgrade the frequency
allocations of federal government Radiolocation Service, and federal and
non-federal government Space Research Service (active) and the Earth
Exploration-Satellite Service (active) in the 5 GHz frequency range.
Upgrading these allocations is consistent with the allocations adopted
internationally, and will provide the necessary protection to federal
systems supporting national defense as well as federal and non-federal
commercial and scientific operations. In addition to the allocation
upgrades in the 5 GHz frequency range, several footnotes were adopted at
the World Radiocommunication Conference 2003 (WRC-2003). There were also
modifications made to several existing footnotes in the 5 GHz frequency
range. The Commission's proposal to modify the U.S. Table of Frequency
Allocations did not include the new footnotes or the modifications to
existing footnotes that were adopted at WRC-2003. NTIA believes that the
modifications to the U.S. Table of Frequency Allocations should include
the appropriate new footnotes and modifications to existing footnotes
adopted at WRC-2003. NTIA believes that the inclusion of these new
footnotes and the modifications to existing footnotes are necessary
because of the complex sharing arrangements that exist between the
diverse federal and non-federal government radio services operating in
the 5 GHz frequency range.

NTIA supports the Commission's proposal to modify the Part 15 Rules to
allow U-NII devices to operate in the 5.47-5.725 GHz band on a
non-interference basis. Utilization of the mitigation measures proposed
in the NPRM along with the additional 255 MHz of spectrum for U-NII
devices to spread across will provide protection to vital government
systems. The Commission's proposal will also meet current industry needs
as well as future growth in the radio local area network radio local
area network (RLAN) industry which has proven to be one of the few
technology success stories in the current economy.

NTIA concurs with the Commission's proposal that Dynamic Frequency
Selection (DFS) should be required in the existing 5.25-5.35 GHz U-NII
band as well as the proposed U-NII 5.47-5.725 GHz band. NTIA also
concurs with the technical limits on DFS proposed by the Commission.
Comprehensive studies carried out jointly between NTIA, Department of
Defense, and private industry with Commission representatives has proven
the requirement for these technical limits. Specifically, NTIA considers
the proposed power limits, detection threshold, move time, and
non-occupancy period as fundamental for the protection of government
radars and no relaxation in the proposed values can be accepted based on
the studies cited above. DFS is an integral part of the protection
measures that allows for sharing between the U-NII devices and existing
primary government users. NTIA is of the opinion that the DFS mechanism
should be required to detect a single radar pulse present during
coincidence of the transmitted radar pulse and the dedicated listen
period of the DFS mechanism between each packet/frame. The requirement
should be for detection of a single pulse during this coincidence
period. In addition, the DFS mechanism should be allowed to average
received power over successive 1 microsecond periods during the
dedicated listen period. Given the typical pulse widths and pulse
repetition rates of the radars operating in these bands, as well as the
average power levels transmitted by these radars, the DFS mechanism
should have no problems detecting single radar pulses during
coincidence. This will not allow for radar signal detection and instead
forces the DFS to rely on signal detection above the DFS detection
threshold no matter the source. This provides further protection of
radar systems given the high probability of masking of radar signals
from adjacent, competing U-NII devices.

NTIA's Office of Spectrum Management is leading a government/industry
project team to develop proposed compliance measurement procedures for
DFS equipped U-NII devices. This project team will be responsible for
addressing technical issues related to the generation of radar signals
and the techniques to reliably measure these signals. NTIA believes that
this government/industry project team has the expertise to provide
guidance to the Commission in the development of the compliance
measurement procedures for DFS equipped U-NII devices. A first draft of
the proposed compliance measurement procedures is provided as part of
these comments. There are plans in the November 2003 timeframe for
manufacturers to bring DFS equipped devices to NTIA's Institute for
Telecommunication Sciences to validate the draft measurement procedures.
This testing will be dependent on the availability of DFS equipped U-NII
devices. NTIA will submit a report to the Commission documenting the
results of these measurements and any modifications to the draft
procedures. NTIA believes that providing the draft measurement
procedures to the Commission as part of the public record will allow
other parties that are not participating in the government/industry
project team to review and provide comments on the proposed measurement
procedures.

The current Institute of Electrical and Electronics Engineers (IEEE)
802.11 standards require Transmitter Power Control (TPC) in both the
5.25-5.35 GHz and 5.47-5.725 GHz bands as a means to facilitate sharing
among U-NII devices. Therefore, NTIA believes that it should not create
a burden on industry to implement TPC in both bands. NTIA believes that
TPC will provide a mitigation factor of at least 3 dB within the
EESS/SRS satellite footprint providing additional protection for these
critical government operations.

NTIA agrees with the Commission's transition schedule for domestically
manufactured U-NII devices operating in the 5.25-5.35 GHz band. NTIA
believes that this approach will lessen the burden on manufacturers by
allowing them adequate time to redesign their devices to comply with the
DFS and TPC requirements necessary to protect federal systems. NTIA
recommends that the Commission require that imported U-NII devices
operating in the 5.25-5.35 GHz band adhere to the Commission's Rules
(e.g., DFS and TPC), one year after the date of publication of the
Report and Order in the Federal Register.

Finally, NTIA recommends that the Commission include additional
definitions in their rules for U-NII devices. The additional definitions
proposed by NTIA are consistent with the terminology employed by the
RLAN industry, and will help to avoid confusion that may arise when
developing compliance measurement procedures for U-NII devices.

**Before the**

**FEDERAL COMMUNICATIONS COMMISSION**

**Washington, DC 20554**

+-----------------------------------+---+------------------------------+
| In the Matter of                  | ) | ET Docket No. 03-122         |
|                                   |   |                              |
| Revision of Parts 2 and 15 of the | ) | RM - 10371                   |
| Commission's Rules to Permit      |   |                              |
| Unlicensed National Information   | ) |                              |
| Infrastructure (U‑NII) Devices in |   |                              |
| the 5 GHz Band                    | ) |                              |
|                                   |   |                              |
|                                   | ) |                              |
|                                   |   |                              |
|                                   | ) |                              |
|                                   |   |                              |
|                                   | ) |                              |
+-----------------------------------+---+------------------------------+

**[COMMENTS OF THE NATIONAL TELECOMMUNICATIONS]{.underline}**

**[AND INFORMATION ADMINISTRATION]{.underline}**

The National Telecommunications and Information Administration (NTIA),
an Executive Branch agency within the Department of Commerce, is the
President's principal adviser on domestic and international
telecommunications policy, including policies relating to the Nation's
economic and technological advancement in telecommunications.
Accordingly, NTIA makes recommendations regarding telecommunications
policies and presents Executive Branch views on telecommunications
matters to the Congress, the Federal Communications Commission
(Commission), and the public. NTIA, through the Office of Spectrum
Management, is also responsible for managing the Federal Government's
use of the radio frequency spectrum. NTIA respectfully submits the
following comments in response to the Commission's Notice of Proposed
Rulemaking (NPRM) in the above-captioned proceeding.[^1]

**I. INTRODUCTION**

The U-NII NPRM is seeking comments on the feasibility of allowing
unlicensed devices to operate in additional frequency bands.
Specifically, the NPRM proposes to amend Part 15 of the Commission's
Rules governing the operation of Unlicensed National Information
Infrastructure (U‑NII) devices, including Radio Local Area Networks
(RLANs), to make available an additional 255 megahertz of spectrum in
the 5.47--5.725 GHz band, and on the technical requirements that would
be necessary to ensure that such devices do not cause interference to
authorized services operating within the 5.25-5.35 GHz and 5.47-5.725
GHz bands.[^2] The Commission also proposes other changes to the United
States (U.S.) Table of Frequency Allocations to accommodate the needs of
other radio services operating in the 5 GHz region of the spectrum.
Finally, the Commission proposes to modify certain technical
requirements for U‑NII devices in the Part 15 Rules to protect various
radio services against harmful interference.[^3] These proposals are
consistent with the outcome of the World Radiocommunication Conference
2003 (WRC-2003) and the subsequent changes to the international Radio
Regulations.

NTIA commends the Commission for initiating this proceeding to expand
the options for unlicensed device use and particularly, linking such
expanded use to adoption of new technologies for active interference
avoidance. NTIA agrees with the Commission regarding the significant
benefits to the economy, businesses, consumers, and government agencies
that could be gained by allowing unlicensed devices to operate in the
5.47-5.725 GHz frequency range, provided that such use is tied to
effective implementation of active interference avoidance techniques.
NTIA would also like to commend the Commission for its careful
consideration and review of existing Part 15 Rules in the 5.25-5.35 GHz
band as well as consideration of the federal government and private
sector spectrum requirements in the 5 GHz frequency range. NTIA provides
the following comments in response to specific issues raised in the
U-NII NPRM.

**II. NTIA SUPPORTS THE COMMISSION'S PROPOSAL TO CHANGE THE U.S. TABLE
OF FREQUENCY ALLOCATIONS TO ACCOMMODATE THE NEEDS OF FEDERAL AND
NON-FEDERAL GOVERNMENT RADIO SERVICES OPERATING IN THE 5 GHZ FREQUENCY
RANGE.**

In the U-NII NPRM, the Commission proposes to modify the U.S. Table of
Frequency

Allocations to upgrade the status of the federal government
Radiolocation Service to primary in the 5.46--5.65 GHz band.[^4] The
Commission further proposes to add primary allocations for the federal
government and secondary allocations for the non-federal government
Space Research Service (active) (SRS) in the 5.35-5.57 GHz band and the
Earth Exploration-Satellite Service (active) (EESS) in the 5.46‑5.57 GHz
band.[^5] The Commission also proposes to upgrade the allocation status
of non-federal government Radiolocation to primary in the 5.47-5.65 GHz
band.[^6]

The Department of Defense (DoD) operates numerous radars in the
5.25-5.925 GHz frequency range in support of national defense, military
test range surveillance and instrumentation operations, airborne radar
transponders, battlefield missile surveillance and tracking, weather
radar observations, shipborne missile and gunfire control, and
navigational aids to assist precision positioning of ships.[^7]
Non-military government radar operations in the 5.25-5.925 GHz frequency
range include support for airborne weather and navigation, weather
phenomena research studies, and airport terminal Doppler weather
radars.[^8] Appendix A provides a description of radar usage in the 5
GHz frequency range.

The primary factors driving the need for additional radar spectrum
include changes in requirements, missions, and technology which result
in the use of narrow pulse widths, and wide emission bandwidths to
achieve the resolution necessary to detect smaller and less reflective
targets in the presence of background clutter.[^9] Given the increasing
demands for spectrum in the 5.25-5.925 GHz frequency range to support
radar system development, there is a need to upgrade the allocations of
the federal government radiolocation spectrum allocated on a secondary
basis to primary. Upgrading the allocation from secondary to primary in
the 5.46-5.65 GHz frequency range will provide the same regulatory
protection throughout the entire tuning range of these radar systems.
This upgrade to primary allocation is necessary to safeguard the
operation of existing and future radar operations in the 5 GHz frequency
range from potential interference resulting from the increased sharing
demands to accommodate new licensed and unlicensed radio services.

Active sensing is the measurement on board a spacecraft of signals
transmitted by a sensor and then reflected, refracted, or scattered by
the Earth's surface or its atmosphere. Prior to WRC-2003, the U.S.
Government identified a requirement to expand the bandwidth available
for spaceborne altimeters and synthetic aperture radars (SARs) operating
in the EESS (active) in the 5.25-5.46 GHz band from 210 MHz to 320 MHz
(5.25-5.57 GHz). This increase in spectrum is necessary to satisfy a
requirement for altimeter height measurements with a standard deviation
of 1 to 2.5 centimeters and a SAR requirement for measurements with
enhanced ground resolution of 1 meter. The higher quality data collected
using wideband SARs will allow scientist to gain new insights into the
prediction of climatic changes. These wideband SARs will also provide
the higher resolution necessary for commercial applications, such as
high-resolution surface mapping. For example, by increasing the
bandwidth available to SARs it will be possible to precisely map the
boundary of oil spills to a resolution of 1 meter.

NTIA supports the Commission's proposals to upgrade the frequency
allocations of federal government Radiolocation, and federal and
non-federal government SRS (active) and EESS (active) in the 5 GHz
frequency range. Upgrading these allocations is consistent with the
allocations adopted internationally, and will provide the necessary
protection to federal systems supporting national defense as well as
federal and non-federal commercial and scientific operations. NTIA notes
that the U-NII NPRM does not include the new footnotes or the
modifications to existing footnotes that were adopted at WRC-2003.[^10]
NTIA believes that the modifications to the U.S. Table of Frequency
Allocations should include the appropriate new footnotes and
modifications to existing footnotes adopted at WRC-2003. NTIA recommends
that the Commission include the following new footnotes in the U.S.
Table of Frequency Allocations:

**USXXX\--**Federal Government stations in the radiolocation service
operating in the band 5350-5470 MHz, shall not cause harmful
interference to, nor claim protection from, Federal stations in the
aeronautical radionavigation service operating in accordance with No.
5.449.

**USYYY\--**Federal Government stations in the radiolocation service
operating in the band 5470-5650 MHz, with the exception of ground based
radars used for meteorological purposes operating in the band 5600-5650
MHz, shall nor cause harmful interference to, nor claim protection from,
Federal Government stations in the maritime radionavigation service.

**USZZZ**\--Federal Government stations in the space research service
(active) operating in the band 5350-5460 MHz shall not cause harmful
interference to nor claim protection from Federal Government and
non-Federal Government stations in the aeronautical radionavigation
service nor Federal Government stations in the radiolocation service.

NTIA also recommends that the following modifications adopted at
WRC-2003 to international footnotes 5.448A and 5.448B be reflected in
the U.S. Table of Frequency Allocations:

**5.448A \--**~~The use of the frequency band 5250-5350 MHz by the earth
exploration-~~ ~~satellite (active) and space research (active) services
shall not constrain the future~~ ~~development and deployment of the
radiolocation service.~~ **The Earth exploration-satellite (active) and
space research (active) services in the frequency band 5250-5350 MHz
shall not claim protection from the radiolocation service.**

**5.448B\--**~~The earth exploration-satellite (active) service
operating in the band~~ ~~5350-5460 MHz shall not cause harmful
interference to, or constrain the use and~~ ~~development of, the
aeronautical radionavigation service.~~ **The Earth
exploration-satellite service (active) operating in the band 5350-5570
MHz and space research service (active) operating in the band 5460-5570
MHz shall not cause harmful interference to the aeronautical
radionavigation service in the band 5350-5460 MHz, the radionavigation
service in the band 5460-5470 MHz and the maritime radionavigation
service in the band 5470- 5570 MHz.**

NTIA believes that the inclusion of these new footnotes and the
modifications to existing footnotes are necessary because of the complex
sharing arrangements that exist between the diverse federal and non
federal government radio services operating in the 5 GHz frequency
range. These new footnotes and modifications to the existing footnotes
were supported as the U.S. position for WRC-2003.

**III. NTIA SUPPORTS THE COMMISSION'S PROPOSAL TO MODIFY THE PART 15
RULES TO ACCOMMODATE EXPANDED USE OF U-NII DEVICES.**

The Commission is proposing to modify the Part 15 rules to allow U-NII
devices to

operate in the 5.47-5.725 GHz band on a non-interference basis. This
proposal will increase the

available spectrum available for U-NII devices by 255 MHz, facilitating
the development of a

wide range of new and innovative unlicensed devices. The Commission
seeks comment on this

proposal.[^11]

NTIA supports the Commission's proposal to modify the Part 15 Rules to
allow U-NII devices to operate in the 5.47-5.725 GHz band on a
non-interference basis. Utilization of the mitigation measures proposed
in the NPRM along with the additional 255 MHz of spectrum for U-NII
devices to spread across will provide protection of the vital government
systems. The Commission's proposal will also meet current industry needs
as well as future growth in the RLAN industry which has proven to be one
of the few technology success stories in the current economy.

**IV. NTIA SUPPORTS THE COMMISSION'S PROPOSAL TO REQUIRE U-NII DEVICES
OPERATING IN THE 5.25-5.35 GHZ AND 5.47-5.725 GHZ FREQUENCY BANDS TO
EMPLOY DFS TO AVOID INTERFERING WITH CRITCAL FEDERAL RADAR OPERATIONS.**

In order to ensure protection of existing radar operations, the
Commission is

proposing that U-NII devices authorized to operate in the 5.25-5.35 GHz
and 5.47-5.725

GHz bands employ a listen-before-talk mechanism referred to as Dynamic
Frequency Selection

(DFS). DFS is an interference avoidance mechanism, that when employed in
a U-NII device, will monitor the radio environment for the presence of a
radar.[^12] For systems, where multiple devices operate under a central
controller, the Commission is proposing that only the central controller
have DFS capability. The Commission is seeking comment on requiring
U-NII devices to have DFS and how to identify remote units that operate
under the control of a central controller.[^13] The Commission is also
seeking comment on the minimum number of pulses needed for a DFS system
to reliably detect a radar signal.[^14]

NTIA concurs with the Commission's proposal that DFS should be required
in the existing 5.25-5.35 GHz U-NII band as well as the proposed U-NII
5.47-5.725 GHz band. NTIA also concurs with the technical limits on DFS
proposed by the Commission. Comprehensive studies carried out jointly
between NTIA, DoD, and private industry with Commission representatives
have proven the requirement for these technical limits. Specifically,
NTIA considers the proposed power limits, detection threshold, move
time, and non-occupancy period as fundamental for the protection of
government radars and no relaxation in the proposed values can be
accepted based on the studies cited above. DFS is an integral part of
the protection measures that allows for sharing between the U-NII
devices and existing primary government users. NTIA is of the opinion
that the DFS mechanism should be required to detect a single radar pulse
present during coincidence of the transmitted radar pulse and the
dedicated listen period of the DFS mechanism between each packet/frame.
Setting a specific hard number of pulses before detection is difficult
given that coincidence between a radar pulse and listen period is
statistical in nature based on packet/frame length and probability of a
radar pulse being present during the listen period as based on radar
pulse width and pulse repetition rate as well as antenna pointing angle
(radar antenna scan function) with respect to the U-NII device. The
requirement should be for detection of a single pulse during this
coincidence period. In addition, the DFS mechanism should be allowed to
average received power over successive 1 microsecond periods during the
dedicated listen period. Given the typical pulse widths and pulse
repetition rates of the radars operating in these bands, as well as the
average power levels transmitted by these radars, the DFS mechanism
should have no problem detecting single radar pulses during coincidence.
This will not allow for radar detection and instead forces the DFS to
rely on signal detection above the DFS detection threshold no matter the
source. This provides further protection of radar systems given the high
probability of masking of radar signals from adjacent, competing U-NII
devices.

Internationally, there is also a requirement for a dedicated 10 minute
monitoring period as part of the required non-occupancy period for
channels on which the detection threshold is exceeded in the 5.6-5.65
GHz band. NTIA concurs with the Commission in excluding this from the
domestic rulemaking. The joint studies clearly show that the required 30
minute non-occupancy period that was included in the U-NII NPRM is
sufficient to provide protection to circular scanning weather radars
that require protection using the non-occupancy period.

**V. NTIA IS LEADING A PROJECT TEAM WITH GOVERNMENT AND INDUSTRY
REPRESENTATIVES TO DEVELOP COMPLIANCE MEASUREMENT PROCEDURES FOR DFS
ENABLED U-NII DEVICES.**

Determining whether or not a U-NII device with DFS capability can
reliably detect a

radar signal will require very specialized compliance measurement
procedures, that are beyond

the measurement procedures currently found in the Commission's Part 15
Rules. In order to

address this issue the Commission is seeking comment on the appropriate
measurement

procedures to ensure compliance with the requirements for DFS.[^15]

NTIA recognizes the difficulties encountered in reliably detecting radar
signals. NTIA's

Institute for Telecommunication Sciences (ITS) has many years of
experience in detecting and

measuring radar signals. These measurements require very specialized
measurement instruments

and measurement techniques that take into account the characteristics of
the signals being measured (*e.g.*, pulse width, pulse repetition
frequency, antenna scan rate). The test facilities that perform the
Commission's equipment compliance measurements will in all likelihood
not have this specialized measurement equipment or have experience in
generating the radar signals that are necessary to determine whether or
not DFS equipped U-NII devices comply with the Commission's Rules. NTIA
believes that the measurement procedures developed must correctly
determine compliance with the Commission's Rules without undermining the
protection effects of DFS. However, the measurement procedures should
not unnecessarily cause manufacturers to incur undue costs or delays in
the deployment of equipment.

In preparing for WRC-2003, the government (NTIA, Commission, and DoD)
worked

closely with industry representatives to reach agreement on the United
States' 5 GHz proposals for the conference. A similar approach will be
employed to develop a proposal for the compliance measurement procedures
for DFS equipped U-NII devices. NTIA's Office of Spectrum Management is
leading a government/industry project team to develop proposed
compliance measurement procedures. This project team will be responsible
for addressing technical issues related to the generation of radar
signals and the techniques to reliably measure these signals. NTIA
believes that this government/industry project team has the expertise to
provide guidance to the Commission in the development of the compliance
measurement procedures. A first draft of the compliance measurement
procedures is provided in Appendix B. There are plans in the November
2003 timeframe for manufacturers to bring DFS equipped devices to ITS to
validate the draft measurement procedures in Appendix B. This testing
will be dependent on the availability of DFS equipped U-NII devices.
NTIA will submit a report to the Commission documenting the results of
these measurements and any modifications to the draft procedures in
Appendix B. NTIA believes that providing the draft measurement
procedures to the Commission as part of the public record will allow
other parties that are not participating in the government/industry
project team to review and provide comments on the measurement
procedures. A schedule of the project team's projected milestones is
provided in Appendix C.

**VI. NTIA SUPPORTS IMPLEMENTING TPC IN BOTH THE 5.25-5.35 GHZ AND
5.47-5.725 GHZ FREQUENCY BANDS.**

The Commission is proposing to require a transmit power control (TPC)
mechanism in the 5.47-5.725 GHz frequency band to further reduce the
potential impact on EESS and SRS operations. Consistent with the U.S.
proposals to the WRC-03, the Commission is proposing that U-NII devices
employ a TPC mechanism that will ensure a 6 dB drop in power when
triggered. The Commission seeks comment the appropriate triggering
mechanism and whether TPC should keep a receiver parameter such as
received signal strength, bit error rate, or block error rate below a
certain threshold. The Commission also seeks comment on whether it will
be necessary to require U-NII devices to employ TPC if their maximum
power is 3 dB or more below the maximum permitted under the rules.[^16]

In the U-NII NPRM the Commission proposes that U-NII devices employ a
TPC mechanism that will ensure a 6 dB drop in the transmit power when
triggered.[^17] However, NTIA believes that the correct amount of
reduction should be a 3 dB drop in system power when triggered. Further,
NTIA is of the opinion that recent changes to the international
regulations regarding TPC suggest that a 3 dB drop in system power
should be considered for both the 5.25-5.35 GHz band and the 5.47-5.725
GHz band. The international regulations require:

*that in the bands 5250-5350 MHz and 5470-5725 MHz, systems in the
mobile service shall either employ transmitter power control to provide,
on average, a mitigation factor of at least 3 dB on the maximum average
output power of the systems, or, if transmitter power control is not in
use, then the maximum mean e.i.r.p. shall be reduced by 3 dB.* [^18]

An analysis of this language, taken in context of likely RLAN deployment
shows that for domestic regulations there should be a requirement for
devices to have TPC capability or, a maximum power no greater than 3 dB
below the standard maximum transmit power, for both bands. Any further
definition or requirement with respect to TPC is not required given that
the great preponderance of U-NII devices operate at power levels greater
than 6 dB below the maximum transmit power and this will always provide,
on average, a mitigation factor of at least 3 dB within the EESS/SRS
satellite footprint. Moreover, NTIA believes that since the current
Institute of Electrical and Electronics Engineers (IEEE) 802.11
standards require TPC in both of these bands as a means to facilitate
sharing among U-NII devices it should not create a burden on industry to
implement TPC in both the 5.25-5.35 GHz and 5.47-5.725 GHz frequency
bands.

**VII. NTIA RECOMMENDS THAT U-NII DEVICES OPERATING IN THE 5.25-5.35 GHZ
BAND THAT ARE IMPORTED SHOULD ADHERE TO THE COMMISSION'S PROPOSED
TRANSITION SCHEDULE FOR DOMESTIC DEVICES.**

> The NPRM acknowledges that U-NII devices are currently operating in
> the 5.25-5.35

GHz band without DFS capability. To address this issue the Commission
proposes that all U-NII devices certified one year after the Report and
Order is published in the Federal Register must employ DFS. The
Commission also proposes that all U-NII devices operating in the
5.25-5.35 GHz band that are imported or shipped in the interstate
commerce on or after two years from the date of publication in the
Federal Register must comply with these standards.[^19]

NTIA agrees with the Commission's transition schedule for domestically
manufactured U-NII devices operating in the 5.25-5.35 GHz band. NTIA
believes that this approach will lessen the burden on manufacturers by
allowing them adequate time to redesign their devices to comply with the
DFS and TPC requirements that are necessary to protect federal systems.
NTIA recommends that the Commission require that imported U-NII devices
operating in the 5.25-5.35 GHz band also adhere to the Commission's
Rules (*e.g.*, DFS and TPC), one year after the date of publication of
the Report and Order in the Federal Register.

**VIII. IN ORDER TO AVOID CONFUSION, NTIA RECOMMENDS THAT ADDITIONAL
DEFINITIONS BE INCLUDED IN THE COMMISSION'S RULES FOR U-NII DEVICES.**

In the U-NII NPRM, the Commission proposes that when multiple devices
operate under a central control that only the central controller be
required to employ DFS capability, however, the Commission does not
provide a definition for the controller.[^20] In §15.407(h)(2)(a)(i) and
(ii) of the proposed rules, the Commission makes reference to master and
slave operational modes of the U-NII devices, without providing
definitions for either operational mode.[^21] NTIA believes that based
on the terminology used by the RLAN industry that the controller is a
Master Device. The RLAN industry uses very specific terminology to
describe U-NII devices and the operating relationship between these
devices. Understanding the relationship between the different
operational modes of U-NII devices is important when applying the DFS
technical requirements specified in the Commission's Rules. NTIA
believes that in order to avoid confusion, the following definitions
should be included in the Commission's Rules in Section 15.403 for U-NII
devices:

**Channel:** amount of spectrum used by a single U-NII device operating
on one of the specific carrier frequencies.

**Client Device:** a U-NII device operating in Client mode.

**Client Mode:** operating mode in which the transmissions of the U-NII
device are under the control of the Master. A U-NII device in Client
mode is not able to initiate a network.

**Master Device:** a U-NII device operating in Master mode.

**Master Mode:** operating mode in which the U-NII device 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 U-NII devices. A U-NII network has at least
one device operating in Master mode.

NTIA also believes that Section 15.407(h)(2)(a)(i) and (ii) of the
Commission's Rules should be amended as follows:

> a\) Operational Modes. The DFS requirement applies to the following
> operational modes:
>
> i\) The requirement for channel availability check time applies in the
> ~~master~~ ~~operational mode~~ **Master Mode**.
>
> ii\) The requirement for channel move time applies in both the
> ~~master and slave operational modes~~ **Master Mode and Client
> Mode.**

NTIA believes that these definitions are consistent with the terminology
employed by the RLAN industry, and including them in the Commission's
Rules will help to avoid confusion that may arise when applying the DFS
technical requirements.

**IX. CONCLUSION**

NTIA commends the Commission for initiating this proceeding to expand
the options for unlicensed device use. NTIA agrees with the Commission
regarding the significant public benefits that could be gained by
increasing the spectrum available for unlicensed devices, provided that
such use is tied to effective implementation of active interference
avoidance techniques. NTIA will continue to work with the Commission and
industry to resolve the technical issues surrounding the successful
implementation of DFS equipped U-NII devices in an effort to continue
the workable arrangement of facilitating the development and deployment
of unlicensed wireless devices while protecting critical federal
systems.

Respectfully submitted,

Michael D. Gallagher Kathy D. Smith

Acting Assistant Secretary for Chief Counsel

Communications and Information

Fredrick R. Wentland National Telecommunications

Associate Administrator and Information Administration

Office of Spectrum Management U.S. Department of Commerce

Room 4713

Charles T. Glass 1401 Constitution Avenue, N.W.

Telecommunications Specialist Washington, DC 20230

Office of Spectrum Management (202) 482-1816

Edward F. Drocella

Robert L. Sole

Electronics Engineers

Office of Spectrum Management

October 1, 2003

**APPENDIX A**

**DESCRIPTION OF RADAR USAGE IN THE**

**5 GHZ FREQUENCY RANGE**

## INTRODUCTION {#introduction .unnumbered}

There is a presumption that all Federal Government radar systems
operating in the 5 GHz frequency bands have the same technical
characteristics and operate on military installations geographically
separated from heavily populated areas. This section of the report
provides a description of the federal radar usage in the 5 GHz frequency
bands. To describe the radar usage in the 5 GHz frequency range, the
four distinct frequency bands will be considered. The four frequency
bands are: 5250-5350 MHz, 5470-5600 MHz, 5650-5670 MHz, and 5650-5725
MHz. The spectral occupancy and the anticipated future development of
radars in the 5250-5725 MHz frequency range are also discussed.

##  {#section .unnumbered}

## FEDERAL RADARS OPERATING IN THE 5250-5350 MHZ BAND {#federal-radars-operating-in-the-5250-5350-mhz-band .unnumbered}

The Federal Government radar systems operating in the 5250-5350 MHz band
are primarily used by the military. These military radars have the
operational capability to tune across the entire 5250-5725 MHz frequency
range. The military radars that operate in this include both target
search and tracking radars that can use a single frequencies or can
employ frequency hopping using frequencies across the entire band. In
the past these radars have been limited to operating on or near military
installations. However, this was based on the military's usage prior to
the terrorist attacks on September 11, 2001. One of the areas of concern
in assessing interference to military radars regards future radar
deployments and the expanding role of military radars in support of
homeland defense. This expanded role could result in a requirement to
deploy military radars in cities and near highways.

##  {#section-1 .unnumbered}

## FEDERAL RADARS OPERATING IN THE 5470-5600 MHZ BAND {#federal-radars-operating-in-the-5470-5600-mhz-band .unnumbered}

The radars that operate in the 5470-5500 MHz band used by military
systems that are capable of tuning across the entire 5400-5900 MHz
frequency range. The 5470-5600 MHz frequency band is also used by marine
radars that are used for maritime navigation. The marine radar provides
ships with surface search, navigation capabilities, and tracking
services, particularly in inclement weather. These navigation radars are
used by all categories of commercial and Government vessels, including
foreign and U.S. flagged cargo, oil tankers and passenger ships
operating in U.S. waters, and is vital sensor for safe navigation of
waterways. The marine navigation radar provides indications and data on
surface craft, obstructions, buoy markers, and navigation marks to
assist in navigation and collision avoidance. Emissions from maritime
radionavigation radars are observable at distances of at least several
kilometers inland. The emissions are strong in the vicinity of the
shoreline, on bridges near waterways, and coastlines.

### FEDERAL RADARS OPERATING IN THE 5600-5650 MHZ BAND {#federal-radars-operating-in-the-5600-5650-mhz-band .unnumbered}

The 5600-5650 MHz band is used by Terminal Doppler Weather Radar (TDWR)
which provides quantitative measurements of gusts, wind shear, micro
bursts, and other weather hazards for improving the safety of operations
at major airports in the United States. In addition to TDWR,
non-Government meteorological radars operate throughout the 5350-5625
MHz frequency range. In general weather surveillance radars operate near
populated areas.

## FEDERAL RADARS OPERATING IN THE 5650-5725 MHZ BAND {#federal-radars-operating-in-the-5650-5725-mhz-band .unnumbered}

The radars that operate in the 5650-5725 MHz band are used primarily by
military systems that are capable of tuning across the entire 5400-5900
MHz frequency range. The radars operating in this band segment can be
either mobile or transportable and are used for surveillance and test
range instrumentation. Test range instrumentation radars are used for to
provide highly accurate position data on space launch vehicles and
aeronautical vehicles undergoing developmental and operational testing.
Periods of operation can last from minutes up to 4-5 hours, depending
upon the test program that is being supported. Operations are conducted
at scheduled times 24 hours per day, 7 days a week. One of the areas of
concern in assessing interference to military radars regards future
radar deployments and the expanding role of military radars in support
of homeland defense. This expanded role could result in a requirement to
deploy military radars in cities and near highways.

**SPECTRUM OCCUPANCY IN THE 5250-5725 MHZ BAND**

Spectrum occupancy measurements in the 5250-5925 MHz band were performed
by NTIA near the cities of San Diego, Los Angles, San Francisco, and
Colorado.[^22] The activity in the 5250-5925 MHz band in all of these
areas was highly dynamic. Radar measurement personnel have noted that,
during the past 25 years of spectrum survey measurements in the band
5250-5925 MHz, weather and diurnal cycles have had a strong effect on
the levels of occupancy in the band. Based on the measured spectral
occupancy measurements, it is clear that in the frequency range between
5470-5725 MHz, the maximum observed signal levels are much higher as
compared to levels in the other parts of the 5 GHz frequency range.

**ANTICIPATED FUTURE RADAR DEVELOPMEMT TRENDS AT 5 GHZ**

It is not currently known what new radar systems will be developed for
use in the 5250-5725 MHz frequency range in the next few decades. But
the limited amounts of spectrum available for future radar development
makes it likely that new radar systems will be developed in the 5 GHz
frequency range. Current trends in advanced radar design can provide
some guidance as to the likely emission characteristics of such radar
systems. To the extent that these new designs can be anticipated new
services should be designed to be electromagnetically compatible with
future radar systems.

Advanced radar designs are tending toward increased use of modulated
compressed-pulse waveforms. These approaches include various types of
phase coding (e.g., Barker codes, minimum shift keying, etc.) and
frequency modulation (e.g., chirping). Assuming that this trend toward
incorporating larger amounts of information in radar pulses continues,
it can be expected that even compressed pulse lengths will increase.
Already, some 3 GHz radars are transmitting pulse lengths on the order
of 50 microseconds and 100 microseconds pulses are foreseeable. Longer
pulses will tend to increase the average power output of the advanced
radar transmitters. The trend is also toward solid state power output
devices which will have lower peak power levels, resulting in lower
detected power in the receiver systems.

**APPENDIX B**

**DRAFT MEASUREMENT PROCEDURES FOR DFS EQUIPPED U-NII DEVICES**

# Introduction {#introduction-1 .unnumbered}

The purpose of this appendix is to define procedures for testing of the
radar detection capability referred to as Dynamic Frequency Selection
(DFS) of unlicensed U-NII equipment operating in the frequency bands
5250 MHz to 5350 MHz and 5470 MHz to 5725 MHz. These procedures will be
used to test the efficacy of DFS as an interference mechanism as
formulated by the International Telecommunication
Union-Radiocommunications Sector (ITU-R) and documented in
Recommendation ITU-R M.1652 and called for in the U-NII Notice of
Proposed Rulemaking (NPRM).[^23] A major source for the content of this
document is the European Telecommunication Standards Institute (ETSI)
draft EN 301 893 version 1.2.2, which is the approved final European
conformance standard for 5GHz operation. Using ETSI EN 301 893 and its
associated reference documents as baseline for developing this test plan
does not infer that the United States confers with all of the standards,
practices, procedures, and tolerances set within them.

# Scope {#scope .unnumbered}

The scope of this document includes an overview of DFS operational
requirements, the detection and response criteria and methods of
measuring compliance with these criteria. The methods include
calibration and test procedures for conducted and radiated measurements.
Conducted measurements are preferred over radiated measurements because
they are more precise and contain less measurement errors. Equipment
with an integral antenna may be equipped with a temporary antenna
connector in order to facilitate the conducted tests. When the antenna
can not be separated from the device and a radio frequency (RF) test
port is not provided, radiated measurements may be performed.

General information about test sites and measurement techniques are
assumed to be known and not covered here.

Procedures for equipment submission; certification and other regulatory
aspects are not covered in this document.

# References {#references .unnumbered}

> \[1\] Draft New Recommendation ITU-R M.1652
>
> \[2\] Draft EN 301 893 ETSI (RLAN Radio Conformance Test standard)

# Definitions, symbols and abbreviations {#definitions-symbols-and-abbreviations .unnumbered}

## Definitions {#definitions .unnumbered}

For the purposes of the present document, following terms and
definitions apply.

**5 GHz U-NII bands:** Frequency ranges: 5150 - 5250 MHz,
5250 - 5350 MHz, 5470 - 5725 MHz and 5725  5825 MHz.

**Association:** an active relationship between two wireless devices in
which one device (referred to as "Master device" in this document)
exercises certain control functions to which the other device (referred
to as "Client device" in this document) has to respond.

**Burst:** a period during which radio waves are intentionally
transmitted, preceded and succeeded by periods during which no
intentional transmission is made.

**Channel:** amount of spectrum used by a single unlicensed U-NII device
operating on one of the specified carrier frequencies

**Channel Availability Check Time:** the time during which a channel
shall be checked for the presence of a radar signal with a level above
the Interference Detection Threshold. No transmissions shall occur
during this time.

**Channel Closing Transmission Time:** the aggregate duration of
transmissions of control information by unlicensed U-NII devices during
the Channel Move Time which starts upon detection of an interfering
signal above the Interference Detection Threshold*.* The aggregate
duration of all transmissions shall not count quiet periods in between
transmissions.

**Channel Move Time:** the time taken by an unlicensed U-NII device to
cease all transmissions on the current channel upon detection of an
interfering signal above the Interference Detection Threshold.

**Client Device:** an unlicensed U-NII device operating in Client mode.

**Client mode:** operating mode in which the transmissions of the
unlicensed U-NII device are under control of the Master. An unlicensed
U-NII device in Client mode is not able to initiate a network.

**In-Service Monitoring:** a mechanism to check a channel in use by the
unlicensed U-NII device for the presence of a radar signal with a level
above the Interference Detection Threshold.

**Interference Detection Threshold** is the level to be used by the DFS
function to detect radar interference.

**Master Device:** an unlicensed U-NII device operating in Master mode.

**Master mode:** operating mode in which the unlicensed U-NII device 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. An unlicensed U-NII
network always has at least one unlicensed device operating in Master
mode.

**Simulated Radar burst:** a series of periodic radio wave pulses,
separated by a period during which no pulses are transmitted.

## Symbols {#symbols .unnumbered}

> For the purposes of the present document, the following symbols apply:
>
> A Measured power output (dBm)
>
> B Radar burst period
>
> Ch~f~ Channel free from radars
>
> Ch~r~ Channel occupied by a radar
>
> D Measured power density
>
> E Field strength
>
> E~o~ Reference field strength
>
> f~c~ Carrier frequency
>
> G Antenna gain (dBi)
>
> L Radar burst length
>
> n Number of channels
>
> P~H~ Calculated EIRP at highest power level
>
> P~L~ Calculated EIRP at lowest power level
>
> PD Calculated power density
>
> R Distance
>
> R~o~ Reference distance
>
> S0 Signal power
>
> T0 Time instant
>
> T1 Time instant
>
> T2 Time instant
>
> T3 Time instant
>
> W Radar pulse width
>
> x Observed duty cycle

## Abbreviations {#abbreviations .unnumbered}

> For the purposes of the present document, the following abbreviations
> apply:
>
> DFS Dynamic Frequency Selection
>
> EMC Electro-Magnetic Compatibility
>
> EIRP Equivalent Isotropic Radiated Power
>
> LV Low Voltage
>
> PRF Pulse Repetition Frequency
>
> RE Radio Equipment
>
> UUT Unit Under Test

# Technical Requirements for DFS {#technical-requirements-for-dfs .unnumbered}

## DFS Overview {#dfs-overview .unnumbered}

An unlicensed U-NII network shall employ a DFS function to:

-   detect interference from other systems and to avoid co-channel
    operation with these systems, notably radar systems.

-   provide on aggregate a uniform loading of the spectrum across all
    devices by selecting at startup, at random, on one of the channels
    that the unlicensed device is capable of operating.

The DFS function as described in the present document is not tested for
its ability to detect frequency agile radars. Within the context of the
operation of the DFS function, an unlicensed U-NII device shall operate
in either Master mode or Client mode. Unlicensed devices operating in
Client mode (Client device) can only operate in a network controlled by
a unlicensed U-NII device operating in Master mode (Master device).

The operational behavior and individual DFS requirements that are
associated with these modes are as follows:

### Master Devices {#master-devices .unnumbered}

a)  The Master device shall use a Radar Interference Detection function
    in order to detect radar signals with a level above the
    *Interference Detection Threshold* in the frequency ranges
    5250  5350 MHz and 5470  5725 MHz. Radar detection is not required
    in the frequency range 5150  5250 MHz or 5725  5825 MHz.

b)  The Master device initiates an unlicensed U-NII network by
    transmitting control signals that will enable other unlicensed U-NII
    devices to Associate (participate in a wireless network) with the
    Master device.

c)  Before initiating a network on a Channel, the master shall perform a
    C*hannel Availability Check* for a certain duration (*Channel
    Availability Check Time*) to ensure that there is no radar operating
    on the Channel, using the Radar Interference Detection function
    described under a).

d)  During normal operation, the Master shall monitor the operating
    channel *(In-Service Monitoring)* to ensure that there is no radar
    operating on the channel, using the Radar Interference Detection
    function described under a).

e)  If the Master device has detected a radar signal, during In-Service
    Monitoring as described under d), the operating Channel of the
    unlicensed U-NII network is made unavailable. The Master shall
    instruct all Associated devices to stop transmitting on this
    Channel, which they shall do within the *Channel Move Time*. The
    Aggregate Transmissions during the *Channel Move Time* should be
    limited to the *Channel Closing Transmission Time*.

f)  A Master device shall not attempt to initiate a network on a Channel
    in the frequency range 5600-5650 MHz during a period defined as the
    *Non-Occupancy Period* after a radar has been detected in that
    Channel, regardless of the outcome of any In-Service Monitoring or
    Channel Availability Check procedures. The *Non-Occupancy Period*
    commences at the time the radar was detected in the Channel.

### Client devices {#client-devices .unnumbered}

a)  An unlicensed U-NII Client device shall not transmit before having
    received an appropriate enabling signal from a Master device.

b)  An unlicensed U-NII Client device shall stop all its transmissions
    whenever instructed by a Master device to which it is associated.
    The device shall not resume any transmissions until it has again
    received enabling signals from a Master device.

c)  An unlicensed U-NII Client device that incorporates a Radar
    Interference Detection function shall inform the Master device and
    stop its networks transmission if it detects a radar.

The Master device may implement the Radar Interference Detection
function referred to under a) using another device Associated with the
Master. In such a case, the combination should be tested against the
requirements applicable to the Master.

## Applicability {#applicability .unnumbered}

In Tables 1 and 2 shown below, the applicability of DFS requirements
prior to use of a channel *(Channel Availability Check)* and during
normal operation *(In-Service Monitoring)* for each of the above
mentioned operational modes.

The manufacturer shall state whether the UUT is capable of operating as
a Master and/or as a Client. If the UUT is capable of operating in more
than one operating mode then each operating mode shall be tested
separately.

Table 1: Applicability of DFS requirements prior to use of a channel

+-------------------------------+----------+--------------+------------+
| Requirement                   | Ope      |              |            |
|                               | rational |              |            |
|                               | Mode     |              |            |
+-------------------------------+----------+--------------+------------+
|                               | Master   | Client       | Client     |
|                               |          |              | (with      |
|                               |          | (without     | radar      |
|                               |          | radar        | detection) |
|                               |          | detection)   |            |
+-------------------------------+----------+--------------+------------+
| Non --occupancy period        |          | Not required |            |
|                               |          |              |            |
| (required for band 5600-5650  |          |              |            |
| MHz)                          |          |              |            |
+-------------------------------+----------+--------------+------------+
| Interference Detection        |          | Not required |            |
| Threshold                     |          |              |            |
+-------------------------------+----------+--------------+------------+
| Channel Availability Check    |          | Not required | Not        |
| Time                          |          |              | required   |
+-------------------------------+----------+--------------+------------+
| Uniform Spreading             |          | Not required | Not        |
|                               |          |              | required   |
+-------------------------------+----------+--------------+------------+

Table 2: Applicability of DFS requirements during normal operation

+-------------------------------+----------+-------------+------------+
| Requirement                   | Ope      |             |            |
|                               | rational |             |            |
|                               | Mode     |             |            |
+-------------------------------+----------+-------------+------------+
|                               | Master   | Client      | Client     |
|                               |          |             | (with      |
|                               |          | (without    | radar      |
|                               |          | radar       | detection) |
|                               |          | detection)  |            |
+-------------------------------+----------+-------------+------------+
| Interference Detection        |          | Not         |            |
| Threshold                     |          | required    |            |
+-------------------------------+----------+-------------+------------+
| Channel Closing Transmission  |          |             |            |
| Time                          |          |             |            |
+-------------------------------+----------+-------------+------------+
| Channel Move Time             |          |             |            |
+-------------------------------+----------+-------------+------------+

## Detection Threshold values {#detection-threshold-values .unnumbered}

The following tables give the DFS thresholds for Master devices and for
Client devices.

Table 3A: Interference Threshold values, Master

+---------------------------------------------+------------------------+
| Maximum Transmit Power                      | Value                  |
|                                             |                        |
|                                             | (see note)             |
+---------------------------------------------+------------------------+
| 200 mW                                      | -64 dBm                |
+---------------------------------------------+------------------------+
| 200 mW                                      | -62 dBm                |
+---------------------------------------------+------------------------+
| Note: This is the level at the input of the |                        |
| receiver assuming a 0 dBi receive antenna   |                        |
+---------------------------------------------+------------------------+

Table 3B: Interference Threshold values, Client

  ---------------------------------------------- ------------------------
  Maximum Transmit Power                         Value

  200 mW                                         -64 dBm

  200 mW                                         -62 dBm

  Note: This is the level at the input of the    
  receiver assuming a 0 dBi receive antenna      
  ---------------------------------------------- ------------------------

## Response Requirements {#response-requirements .unnumbered}

The following table gives the response requirements for DFS
implementation.

Table 4: DFS Response requirement values

  -------------------------------------------------- --------------------
  Parameter                                          Value

  Non-occupancy period                               30 minutes

  Channel Availability Check Time                    60 s

  Channel Move Time                                  10 s

  Channel Closing Transmission Time                  260 ms
  -------------------------------------------------- --------------------

# Testing for Compliance with Technical Requirements {#testing-for-compliance-with-technical-requirements .unnumbered}

## Radar Test Signals {#radar-test-signals .unnumbered}

The DFS test signals shown in Table 5 shall be used.

Table 5: Parameters of DFS test signals

+----------------------+----------+-----+-----------+------+--------+
| Radar test signal    | Pulse    | Pu  | Burst     | B    | H      |
|                      | re       | lse | length L  | urst | opping |
|                      | petition | wi  | \[ms\] /  | Pe   |        |
|                      | f        | dth | No. of    | riod | Rate   |
|                      | requency | W   | pulses    | B    |        |
|                      | PRF      | \[µ |           | \[s  | (Note  |
|                      | \[pps\]  | s\] | (Note 1)  | ec\] | 4)     |
|                      |          |     |           | (    |        |
|                      |          |     |           | Note |        |
|                      |          |     |           | 2)   |        |
+----------------------+----------+-----+-----------+------+--------+
| Fixed Frequency      | 700      | 1   | 26 / 18   | 10   | Na     |
| Radar signal 1       |          |     |           |      |        |
+----------------------+----------+-----+-----------+------+--------+
| Fixed Frequency      | 1800     | 1   | 5 / 10    | 2    | Na     |
| Radar signal 2       |          |     |           |      |        |
+----------------------+----------+-----+-----------+------+--------+
| Frequency Hopping    | 3000     | 1   | 100/300   | 10   | 1 kHz  |
| Radar                |          |     |           |      |        |
+----------------------+----------+-----+-----------+------+--------+

> Note 1: This represents the number of pulses seen at the unit under
> test (UUT) per radar scan N = \[{antenna beamwidth (deg)} x {pulse
> repetition rate (pps)}\] / \[{scan rate (deg/s)}\]
>
> Note 2: Burst period represents the time between successive scans of
> the radar beam\
> B = 360/{scan rate (deg/s)}
>
> Note 3: Radar bandwidth is less than that of the unlicensed U-NII
> device.
>
> Note 4: The characteristics of this frequency hopping radar do not
> correspond to any specific system. It can hop across the 5250-5725 MHz
> band. The frequencies will be selected by using a random without
> replacement algorithm until all 475 frequencies have been used. After
> all have been used, the pattern is reset and a new random set is
> generated.

Figure 1: General structure of the DFS test transmission sequences

![](media/image1.png){width="5.708333333333333in"
height="1.7784722222222222in"}

## Test Procedures {#test-procedures .unnumbered}

### DFS Testing {#dfs-testing .unnumbered}

#### Conducted Test conditions {#conducted-test-conditions .unnumbered}

The conformance requirements given in the section on Technical
Requirements for DFS shall be verified under normal operating
conditions, and in each of the stated frequency range(s), and with each
of the applicable radar signals defined in Table 5.

For a UUT with antenna connector(s) and using external antenna(s), or
for a UUT with integral antenna(s) but with a temporary antenna
connector provided, conducted measurements shall be used. In this case,
and if the UUT has a Radar Interference Detection Function, the output
power of the signal generator producing the radar test signals shall
provide a received signal power at the antenna connector of the UUT with
a level equal to (*Interference Detection Threshold* + G), see Tables 3A
and 3B. Parameter G \[dBi\] corresponds to the gain of the antenna
assembly stated by the manufacturer. If more than one antenna assembly
is intended, the gain of the antenna assembly with the lowest gain shall
be used.

For a UUT with integral antenna(s) and without temporary antenna
connector, radiated measurements shall be used. In this case, and if the
UUT has a Radar Interference Detection Function, the output power of the
signal generator shall provide a signal power at the antenna with a
level equal to *Interference Detection Threshold.*

Some of the tests may be performed more readily if the channel selection
mechanism for the uniform spreading requirement can be disabled, for
example, to ensure selection of a channel outside the 5150-5250 MHz and
5725-5825 MHz bands.

It should be noted that once a UUT is powered on, it will not start its
normal operating functions immediately, as it will have to finish its
power-up cycle first (T~power_up~). As such, the UUT, as well as any
other device used in the set-up, may be equipped with a feature that
will indicate its status during the testing, including, for example,
power-up mode, normal operation mode, channel check status and radar
detection event.

#### Conducted Test Configurations {#conducted-test-configurations .unnumbered}

The sections below contain simplified block diagrams that focus on the
radar signal injection path for each of the different conducted set-ups
to be used. The basic set-up is identical for all cases. Full details of
this setup, including calibration, can be found in Annex B to this
document.

#####  Test of the DFS functions of the Master {#test-of-the-dfs-functions-of-the-master .unnumbered}

###### Set-up A: Master with injection at the Master {#set-up-a-master-with-injection-at-the-master .unnumbered}

When the UUT is an unlicensed device operating as a Master, the test
set-up, further referred to as *'Set-up A'* shall be used.

*'Set-up A'* consists of a signal generator connected to the UUT and an
unlicensed device operating as a Client. The latter is assumed to
Associate with the UUT (Master).

Figure 2 shows a block diagram for *'Set-up A.'*

Figure 2: Conducted Set-Up where UUT is a Master and Radar Test Signals\
are injected into the Master

![](media/image2.wmf)

##### Test of DFS functions of the Client {#test-of-dfs-functions-of-the-client .unnumbered}

###### Set-up B: Client with injection at the Master {#set-up-b-client-with-injection-at-the-master .unnumbered}

When the UUT is an unlicensed device operating as a Client, with or
without a Radar Interference Detection Function (RIDF), the test set-up,
further referred to as '*Set-up B'* shall be used*.*

*'Set-up B'* consists of a signal generator connected to a unlicensed
device operating as a Master and the UUT. The latter is assumed to
Associate with the Master.

Figure 3 shows an example for *'Set-up B.'* The set-up used shall be
documented in the test report.

Figure 3: Conducted Set-Up B where UUT is a Client and Radar Test
Signals\
are injected into the Master

![](media/image3.wmf)

###### Set-up C: Client with injection at the Client {#set-up-c-client-with-injection-at-the-client .unnumbered}

When the UUT is an unlicensed device operating as a Client with a Radar
Interference Detection Function (RIDF), the tests described in the
section on Test of DFS Function of the Client need to be repeated using
a set-up, further referred to as '*Set-up C.'*

*'Set-up C' consists of a* signal generator connected to the UUT
(Client).

Figure 4 shows an example for *'Set-up C.'*

Figure 4: Conducted Set-Up C - where UUT is a Client and Radar Test
Signals\
are injected into the Client

![](media/image4.wmf)

For the purposes of the test, the UUT as well as other unlicensed U-NII
devices used in the set-up may be equipped with a specific user
interface to allow monitoring of the behavior of the different devices
of the set-up during the tests.

The UUT is capable of transmitting a test transmission sequence. The
signal generator is capable of generating any of the radar test signals
defined in Table 5. Adequate measurement equipment, *e.g.*, spectrum
analyzer, shall be used to measure the aggregate transmission time of
the UUT.

#### Radiated Test conditions {#radiated-test-conditions .unnumbered}

The conformance requirements given in the section on Technical
Requirements for DFS shall be verified under normal operating
conditions, and in each of the stated frequency range(s), and with each
of the applicable radar signals defined in Table 5.

For a UUT with integral antenna(s) and without temporary antenna
connector, radiated measurements shall be used. In this case, and if the
UUT has a Radar Interference Detection Function, the output power of the
signal generator shall provide a signal power at the antenna with a
level equal to *Interference Detection Threshold .*

Some of the tests may be performed more readily if the channel selection
mechanism for the uniform spreading requirement can be disabled, for
example, to ensure selection of a channel outside the 5150-5250 MHz and
5725-5825 MHz bands. It should be noted that once a UUT is powered on,
it will not start its normal operating functions immediately, as it will
have to finish its power-up cycle first (T~power_up~). As such, the UUT,
as well as any other device used in the set-up, may be equipped with a
feature that will indicate its status during the testing, including, for
example, power-up mode, normal operation mode, channel check status and
radar detection event.

#### Radiated Test Configurations {#radiated-test-configurations .unnumbered}

The sections below contain simplified block diagrams that focus on the
radar signal injection path for each of the different radiated set-ups
to be used. The basic set-up is identical for all cases. Full details of
this setup, including calibration, can be found in Annex C to this
document.

##### Test of the DFS functions of the Master {#test-of-the-dfs-functions-of-the-master-1 .unnumbered}

######  Set-up A: Master with injection at the Master {#set-up-a-master-with-injection-at-the-master-1 .unnumbered}

When the UUT is an unlicensed U-NII device operating as a Master, the
test set-up, further referred to as *'Set-up A'* shall be used.

*'Set-up A'* consists of a signal generator connected to the UUT and an
unlicensed U-NII device operating as a Client. The latter is assumed to
be associated with the UUT (Master).

Figure 5 shows a block diagram for *'Set-up A.'*

Figure 5: Radiated Set-Up where UUT is a Master and Radar Test Signals\
are injected into the Master

##### Test of DFS functions of the Client {#test-of-dfs-functions-of-the-client-1 .unnumbered}

###### Set-up B: Client with injection at the Master {#set-up-b-client-with-injection-at-the-master-1 .unnumbered}

When the UUT is an unlicensed U-NII device operating as a Client, with
or without a RIDF, the test set-up, further referred to as '*Set-up B'*
shall be used*.*

*'Set-up B'* consists of a signal generator connected to an unlicensed
U-NII device operating as a Master and the UUT. The latter is assumed to
be associated with the Master.

Figure 6 shows an example for *'Set-up B.'* The set-up used shall be
documented in the test report.

Figure 6: Radiated Set-Up B where UUT is a Client and Radar Test
Signals\
are injected into the Master

###### Set-up C: Client with injection at the Client {#set-up-c-client-with-injection-at-the-client-1 .unnumbered}

When the UUT is an unlicensed U-NII device operating as a Client with a
RIDF, the tests described in Test of DFS Functions as the Client need to
be repeated using a set-up, further referred to as '*Set-up C.'*

*'Set-up C' consists of a* signal generator connected to the UUT
(Client).

Figure 7 shows an example for *'Set-up C.'*

Figure 7: Radiated Set-Up C - where UUT is a Client and Radar Test
Signals\
are injected into the Client

For the purposes of the test, the UUT as well as other unlicensed U-NII
devices used in the set-up may be equipped with a specific user
interface to allow monitoring of the behavior of the different devices
of the set-up during the tests.

The UUT is capable of transmitting a test transmission sequence. The
signal generator is capable of generating any of the radar test signals
defined in Table 5.

Adequate measurement equipment, *e.g.*, spectrum analyzer, shall be used
to measure the aggregate transmission time of the UUT.

#### Radar Signal Generation and Calibration {#radar-signal-generation-and-calibration .unnumbered}

Detailed set-up and instructions for calibration are given in Annexes B
and C.

#### Unlicensed U-NII device initialization {#unlicensed-u-nii-device-initialization .unnumbered}

This section describes the verification procedure for the Channel
Availability Check to be performed at initialization of an unlicensed
U-NII device. See section on DFS overview.

One channel, outside the 5150-5250 MHz and 5725-5825 MHz range, is
selected from the stated operating frequency range(s) of the UUT. This
channel is designated as Ch~r~ (channel occupied by a radar).

The UUT shall be configured to select Ch~r~ as the first operating
channel.

T~ch_avail_check~ is the minimum Channel Availability Check Time as
specified in Table 4.

The different steps below define the procedure to verify the response
behavior parameters when a radar burst is generated on the selected
channel at the beginning or at the end of the Channel Availability Check
Time.

##### Radar burst at the beginning of the Channel Availability Check Time {#radar-burst-at-the-beginning-of-the-channel-availability-check-time .unnumbered}

The steps below define the procedure to verify successful radar
detection on the selected channel during a period equal to the *Channel
Availability Check Time* and avoidance of operation on that channel when
a radar burst with a level equal to the *Interference Detection
Threshold* occurs at the beginning of the Channel Availability Check
Time.

a)  The signal generator and UUT are connected using the applicable test
    set-ups described in section on Conducted Tests and the power of the
    UUT is switched off.

b)  The UUT is powered on at T0. T1 denotes the instant when the UUT has
    completed its power-up sequence (T~power_up~). The channel
    availability check is expected to commence on Ch~r~ at instant T1
    and is expected to end no sooner than T1 + T~ch_avail_check~ unless
    a radar is detected sooner.

c)  Radar bursts are generated on Ch~r~ using one of the test patterns
    defined in Table 5. Radar bursts should commence at time T1 and
    should continue for approximately 6 seconds.

d)  Visual indication on the UUT of successful detection of the radar
    burst (if indication is available) should be recorded. Observation
    of Ch~r~ shall continue until the UUT starts transmitting on another
    channel. *(In the example given below, the UUT performs a channel
    availability check on a new channel after it has detected a radar on
    Ch~r~).* It shall be verified and recorded that during the above
    steps no transmissions occurred on Ch~r.~

e)  A timing trace or description of the observed timing and behavior of
    the UUT should be reported.

Figure 8: Example of timing for radar testing at the beginning of\
the Channel Availability Check Time

![](media/image5.wmf)

##### Radar burst at the end of the Channel Availability Check Time {#radar-burst-at-the-end-of-the-channel-availability-check-time .unnumbered}

The steps below define the procedure to verify successful radar
detection on the selected channel during a period equal to the *Channel
Availability Check Time* and avoidance of operation on that channel when
a radar burst with a level equal to the *Interference Detection
Threshold* occurs at the end of the Channel Availability Check Time.

a)  The signal generator and UUT are connected using the applicable test
    set-ups referred to in section on Conducted Test Configurations and
    the power of the UUT is switched off.

b)  The UUT is powered up at T0. T1 denotes the instant when the UUT has
    completed its power-up sequence (T~power_up~). The channel
    availability check is expected to commence on Ch~r~ at instant T1
    and is expected to end no sooner than T1 + T~ch_avail_check~ unless
    a radar is detected sooner.

c)  Radar bursts are generated on Ch~r~ using one of the test patterns
    defined in section 5.1 at a level defined in the DFS Overview
    section. Radar bursts should commence near the end of the minimum
    required Channel Availability Check Time at time T1 +
    T~ch_avail_check~ -- 6 \[sec\] and should continue for the duration
    of this test.

d)  Visual indication on the UUT of successful detection of the radar
    burst (if indication is available) should be recorded. Observation
    of Ch~r~ shall continue until the UUT starts transmitting on another
    channel. *(In the example given below, the UUT performs a channel
    availability check on a new channel after it has detected a radar on
    Ch~r~).* It shall be verified and recorded that during the above
    steps no transmissions occurred on Ch~r.~

e)  A timing trace or description of the observed timing and behavior of
    the UUT should be recorded.

Figure 9: Example of timing for radar testing towards the end of\
the Channel Availability Check Time

![](media/image6.wmf)

#### In-Service Monitoring {#in-service-monitoring .unnumbered}

These tests define how the following DFS parameters can be verified
during In-Service Monitoring

-   Interference Detection Threshold

-   Channel Closing Transmission Time

-   Channel Move Time

-   Non-Occupancy Period

The steps below define the procedure to determine the above mentioned
parameters when a radar burst with a level equal to the *Interference
Detection Threshold* is generated on the channel of operation of the
unlicensed U-NII device *(In- Service Monitoring).*

a)  A channel outside 5150-5250 MHz and 5725-5825 MHz bands is selected
    from the stated operating frequency range(s).

b)  In case the UUT is an unlicensed U-NII device operating as a Client
    (with or without Radar Interference Detection Function), an
    unlicensed U-NII device operating as a Master will be used to allow
    the UUT to associate with the Master. In case the UUT is a Master,
    an unlicensed U-NII device operating as a Client will be used and it
    is assumed that the Client will associate with the UUT (Master). In
    both cases, the signal generator shall be connected to the Master.

c)  The UUT transmits a test transmission sequence on the selected
    channel.

d)  At a certain time T0 the signal generator starts generating one of
    the radar test patterns defined in Table 5 at a level defined in the
    section on Response Requirements on the selected channel. T1 denotes
    the end of the first radar burst.

e)  The transmissions of the UUT following instant T1 on the selected
    channel shall be observed for a duration of at least 10 seconds. The
    aggregate duration of all transmissions from the UUT during the
    observation time (*Channel Closing Transmission Time)* shall be
    noted and compared to the limit defined in Table 4. Note: the
    aggregate duration of all transmissions of the UUT does not include
    quiet periods in between transmissions of the UUT.

f)  T2 denotes the instant when the UUT has ceased all transmissions on
    the channel. The time difference between T1 and T2 shall be
    measured. This value *(Channel Move Time*) shall be noted and
    compared with the limit defined in Table 4.

g)  When the UUT is an unlicensed U-NII device operating as a Master,
    following instant T2, the selected channel shall be monitored for an
    additional 30 minutes (*Non-Occupancy Period*) until instant T3, to
    verify that the UUT does not resume any transmissions on this
    channel.

h)  The test shall be repeated using each of the radar signals defined
    in the section on Testing for Compliance with Technical
    Requirements;

i)  In case the UUT is an unlicensed U-NII device operating as a Client
    with a Radar Interference Detection Function, the steps a) to h)
    shall be repeated with the generator connected to the UUT.

Figure 10: Channel Closing Transmission Time & Channel Clearing Time

![](media/image7.wmf)

**Annex A**

# General Requirements {#general-requirements .Appendix-1 .unnumbered}

## Product information {#product-information .Appendix-2}

The following information shall be stated by the manufacturer in order
to facilitate the execution of the test suites:

a)  the operating frequency range(s) of the equipment;

b)  the operating modes (Master and/or Client)

c)  the highest and the lowest possible power level (equivalent
    isotropically radiated power (EIRP)) of the equipment;

d)  the intended antenna assemblies and their corresponding gains;

e)  the test sequences or messages used for communication between Master
    and Client devices.

## Interpretation of the measurement results  {#interpretation-of-the-measurement-results .Appendix-2}

The interpretation of the results recorded in a test report for the
measurements described in the present document shall be as follows:

-   the measured value related to the corresponding limit will be used
    to decide whether an equipment meets the requirements of the present
    document;

-   the value of the measurement uncertainty for the measurement of each
    parameter shall be included in the test report;

-   the recorded value of the measurement uncertainty shall be, for each
    measurement, equal to or lower than the figures in Table A.1;

-   the shared risk approach shall be applied for the interpreting of
    all measurement results.

Table A.1: Maximum measurement uncertainty

  ------------------------------------------------ ----------------------
  Parameter                                        Uncertainty

  RF frequency                                     ±1 x 10^-5^

  RF power conducted                               ±1.5 dB

  RF power radiated                                ±2 dB

  Spurious emissions, conducted                    ±3 dB

  Spurious emissions, radiated                     ±2 dB

  Time                                             ±5 %
  ------------------------------------------------ ----------------------

**Channel Loading**

The data test file that is used for transmissions to/from the master and
the client should be constructed so that the data packets are
representative of the weighting factors shown in Table A2 for packet
size and data rate (Annex 4 Table 4 of Recommendation ITU-R M. 1652).

**Table A2**

Weighting of data test file

  ---------------- ---------------- ----- ---------------- ----------------
  Packet size\     Weight                 Data rate        Weight
  (bytes)                                 (Mbit/s)         

  64               0.6                    6                0.1

  538              0.2                    12               0.1

  1 500            0.2                    18               0.1

                                          24               0.3

                                          36               0.3

                                          54               0.1
  ---------------- ---------------- ----- ---------------- ----------------

# Annex B {#annex-b .Appendix-1 .unnumbered}

# Conducted Test Set-up and Calibration {#conducted-test-set-up-and-calibration .Appendix-1 .unnumbered}

## Block Diagram {#block-diagram .Appendix-2}

Conducted measurements are the preferred method to perform these tests.
In this method, cables are used to supply the unlicensed U-NII device
signals to/from the devices under test and the test equipment. Equipment
with an integral antenna may be equipped with a temporary antenna
connector in order to facilitate the conducted tests. Figure B1 shows a
detailed set-up for performing conducted measurements.

Figure B1: Conducted DFS Measurements - Test Set-Up

![](media/image8.wmf)

It is important to note that the Signal Generator used should have the
'Short Pulse' option to guarantee that the Automatic Level Control
circuitry can also deal with short pulses (this will be verified during
the calibration part.). It might be possible that the function of the
Delay/Trigger unit is part of the features of Spectrum Analyzer #1.

The value of the attenuator #1 and attenuator #2 are chosen in such a
way that the received unlicensed U-NII signal (unlicensed U-NII device
#2) at the input of the UUT (unlicensed U-NII device #1) is minimum
about 20 dB above the threshold level to be tested (the received
unlicensed U-NII device signal should be much stronger as the radar test
signals).

The duty cycle of the unlicensed U-NII device transmissions should be
sufficiently high. Also the duration of the unlicensed U-NII device
transmissions should be sufficiently high to allow the measurements to
be repeated a number of times (*e.g.*, 10 times). In order to allow some
of the tests to be repeated on the same channel, it may be required for
the diagnostic software to disable the 'move to a new channel feature'
after a radar pulse was detected the first time, otherwise the whole
set-up need to be re-calibrated on the new frequency.

## Calibration procedure {#calibration-procedure .Appendix-2}

1)  During this calibration, there are no transmissions initiated by the
    UUT.

2)  For calibrating the test set-up (exact threshold level at the UUT,
    unlicensed device #1), the UUT is replaced by a Spectrum Analyzer
    with an accurate power level measurement feature.

3)  The Spectrum Analyzer #2 is switched to Zero Span' mode and to the
    'Time Domain' mode and it shall be verified if the level of each of
    the Radar pulses is identical. This is required to verify the proper
    functioning of ALC circuit of the Signal Generator for short pulses.
    For each of the tests (different radar test signals), the level of
    the Signal Generator is adjusted until the appropriate level (e.g.
    -62 dBm) is measured by the Spectrum Analyzer #2.

4)  The Spectrum Analyzer #1 is switched to 'Zero Span' mode and to the
    'Time Domain' mode with an adaptive sweep time. The time base of the
    Spectrum Analyzer is externally triggered by the Pulse Generator
    through a delay circuit so that the sweep is already started a few
    ms before the first pulse of the Signal Generator appears. This will
    bring the radar burst clearly within the view window of the
    analyzer.

5)  A reference point, indicating the start of the first pulse of the
    radar test signal (often equal to the time of the external trigger)
    should be set (marker T1) before any UUT transmissions are
    initiated.

6)  The Radar Test Signal is switched off.

## Taking Measurements {#taking-measurements .Appendix-2}

-   The Monitor/Diagnostic Device (PC#2) starts transmissions between
    the 2 unlicensed U-NII devices.

-   The Control Device #2 will switch on the Radar Test Signal at the
    instances indicated in the procedures in section 5

-   The screen will now show the behavior of the unlicensed U-NII
    devices to the Radar Test Signal.

Note: it should be possible, with the above described set-up, to
distinguish (on the spectrum analyzer screen) (1) the Radar Test
Signals, (2) U-NII

**Annex C**

# Radiated Test Set-up and Calibration {#radiated-test-set-up-and-calibration .Appendix-1 .unnumbered}

## Block Diagram {#block-diagram-1 .Appendix-2}

Radiated tests may be performed when the antenna of the unlicensed U-NII
device is integral (i.e., the antenna cannot be separated from the
device) and an external antenna port is not provided. Figure C1 shows a
detailed set-up for performing the radiated test measurements.

**Figure C-1.**

**Calibration procedure**

> During this calibration, there are no transmissions initiated by the
> UUT.

1)  For calibrating the test set-up (exact threshold level at the UUT)
    Spectrum analyzer #2 will be used to measure the power output of the
    radar signal simulator for each type of signal in Table 5.

2)  Spectrum Analyzer #2 will be set to zero span mode with the RMS
    detector at the frequency of the chosen unlicensed device channel.
    The resolution and video bandwidth will be set to 1 MHz. The
    unlicensed device integration time as defined by the ITU is 1
    microsecond. In order to achieve this integration time, the sweep
    time of the analyzer must be set appropriately as follows. If the
    analyzer has 1000 points or "bins" across its display, the sweep
    time is equal to that number multiplied by 1 microsecond, or 1
    millisecond. For 8000 points (the maximum on the Agilent E440
    analyzer) the sweep time would be set to 8 milliseconds.

3)  The radar signal generator will be turned on (for each radar type)
    and be allowed to "free run." The pulses will be constantly on and
    not generated in bursts. Note that the frequency hopping radar will
    be set to a fixed frequency.

4)  The step attenuator will be used to adjust the power level at
    Spectrum Analyzer #2 to the level that is required for the tests.

> This value must be adjusted for the gain of the horn antenna connected
> to the analyzer and adjusted once again if the antenna on the
> unlicensed U-NNII device has gain.
>
> The techniques for measuring pulsed emissions from radars can be found
> in ITU-R M.1177-2.

5)  After the attenuator has been adjusted to achieve the proper power
    level the RF output of the simulator will be turned off.

**Taking Measurements**

**Fixed Frequency Radar Simulator**

1)  The power level (-64, -62, -55 dBm) of the radar signal will be
    calibrated for the appropriate radar signal type in Table 5 at the
    antenna of the unlicensed U-NII device. The higher power level (-55
    dBm) will be used to test the DFS functionality of the unlicensed
    device before the ITU detection thresholds are tested.

2)  The unlicensed U-NII devices will be turned on and be instructed to
    operate on the appropriate unlicensed U-NII channel that must
    incorporate DFS functions. Attenuators or some type of power control
    will be used to set the power of the unlicensed link \[to be
    determined\] dB above the radar simulator power.

3)  The radar simulator will be turned on and emulate one of the two
    fixed frequency radars in Table 5 with the appropriate parameters
    (pulsewidth, burst length, and burst period).

4)  Spectrum analyzer #1 and a diagnostic computer/monitor will be used
    to monitor the output of the unit under test (UUT) to observe that
    its behavior is consistent with the channel occupancy and move times
    of ITU-R M.1652.

5)  If the UUT does not properly detect the simulated radar pulses in
    \[to be determined\] minutes the device will not pass the test.

Note that both types of Fixed frequency radars from Table 5 will be
tested.

**Frequency Hopping Radar Simulator**

1)  The power level (-64, -62, -55 dBm) of the radar signal will be
    calibrated for the frequency hopping radar signal type in Table 5 at
    the antenna of the unlicensed U-NII device. The higher power level
    (-55 dBm) will be used to test the DFS functionality of the
    unlicensed device before the ITU detection thresholds are tested.

2)  The unlicensed U-NII devices will be turned on and be instructed to
    operate on the appropriate U-NII channel that must incorporate DFS
    functions. Attenuators or some type of power control will be used to
    set the power of the unlicensed link \[to be determined\] db above
    the radar simulator power.

3)  The radar simulator will be turned on and emulate the frequency
    hopping radar in Table 5 with the appropriate parameters
    (pulsewidth, burst length, burst period, and hopping rate).

4)  Spectrum analyzer #1 and a diagnostic computer/monitor will be used
    to monitor the output of the unit under test (UUT) to observe that
    its behavior is consistent with the channel occupancy and move times
    of ITU-R M.1652.

5)  The UUT will be monitored for \[to be determined\] minutes to
    determine if it can detect the frequency hopping radar.

**APPENDIX C**

**SCHEDULE OF PROJECTED MILESTONES**

**FOR 5 GHZ PROJECT TEAM**

  ---------------------------- -------------- ---------------- ----------------- ------------
  **Task_Name**                **Duration**   **Start_Date**   **Finish_Date**   **Status**

  **Bench Test Procedures**    116 days       9-Jun-03         14-Nov-03         Incomplete

  Draft Bench Test Procedures  39 days        9-Jun-03         31-Jul-03         Yes

  Draft Deadline               1 day          31-Jul-03        31-Jul-03         Yes

  DFS Project Team Meeting     1 day          15-Aug-03        15-Aug-03         Yes

  Finalize Bench Test          11 days        18-Aug-03        31-Aug-03         Yes
  Procedures                                                                     

  Bench Test Procedure         1 day          31-Aug-03        31-Aug-03         Yes
  Deadline                                                                       

  FCC NPRM Comment Reply       1 day          3-Sep-03         3-Sep-03          Yes
  Deadline                                                                       

  Bench Testing                10 days        3-Nov-03         14-Nov-03         Confirmed

                                                                                 

  **Bench Test Report**        76 days        17-Nov-03        1-Mar-04          Incomplete

  Draft Report                 66 days        17-Nov-03        16-Feb-04         Pending

  DFS Project Team Meeting     1 day          15-Jan-04        15-Jan-04         Pending

  DFS Project Team Meeting     1 day          2-Feb-04         2-Feb-04          Pending

  Submit to FCC                1 day          1-Mar-04         1-Mar-04          Pending

                                                                                 

  **Field Test Procedures**    100 days       1-Mar-04         15-Jul-04         Incomplete

  Outline Field Test           34 days        1-Mar-04         15-Apr-04         Pending
  Procedures                                                                     

  Draft Field Test Procedures  22 days        16-Apr-04        16-May-04         Pending

  Draft Deadline               1 day          16-May-04        16-May-04         Pending

  DFS Project Team Meeting     1 day          5-May-04         5-May-04          Pending

  Radar Asset Confirmation     1 day          31-May-04        31-May-04         Pending
  Deadline                                                                       

  DFS Project Team Meeting     1 day          1-Jun-04         1-Jun-04          Pending

  Finalize Field Test          11 days        1-Jun-04         15-Jun-04         Pending
  Procedures                                                                     

  Field Test Procedures        1 day          15-Jun-04        15-Jun-04         Pending
  Deadline                                                                       

  Field Testing                11 days        1-Jul-04         15-Jul-04         Pending

                                                                                 

  **Field Test Report**        66 days        16-Jul-04        15-Oct-04         Incomplete

  Draft Report                 13 days        16-Jul-04        3-Aug-04          Pending

  DFS Project Team Meeting     1 day          31-Jul-04        31-Jul-04         Pending

  DFS Project Team Meeting     1 day          3-Aug-04         3-Aug-04          Pending

  Submit to FCC                1 day          15-Oct-04        15-Oct-04         Pending

                                                                                 

  **Comprehensive NTIA         65 days        19-Oct-04        17-Jan-05         Incomplete
  Report**                                                                       

  Draft Report                 57 days        19-Oct-04        5-Jan-05          Pending

  Report Deadline              1 day          3-Jan-05         3-Jan-05          Pending

  Submit to FCC                1 day          17-Jan-05        17-Jan-05         Pending

                                                                                 

  **ITU Methodology**          296 days       15-Mar-04        29-Apr-05         Incomplete

  Draft DFS Testing Question   192 days       15-Mar-04        6-Dec-04          Pending

  Drafting of DFS Test         106 days       15-Mar-04        6-Aug-04          Pending
  Question                                                                       

  Submit to U.S. Preparatory   1 day          11-Aug-04        11-Aug-04         Pending
  Process                                                                        

  Submit to ITU-R WP 8A        1 day          1-Sep-04         1-Sep-04          Pending

  Draft New Question Deadline  1 day          6-Dec-04         6-Dec-04          Pending

  Draft Methodology            207 days       15-Jul-04        29-Apr-05         Pending
  Recommendation                                                                 

  Drafting of DFS              45 days        15-Jul-04        15-Sep-04         Pending
  Recommendation                                                                 

  Submit to U.S. Preparatory   1 day          17-Sep-04        17-Sep-04         Pending
  Process                                                                        

  Submit to ITU-R WP 8A        1 day          1-Oct-04         1-Oct-04          Pending

  Draft New Recommendation     1 day          29-Apr-05        29-Apr-05         Pending
  Deadline                                                                       
  ---------------------------- -------------- ---------------- ----------------- ------------

[^1]: *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*, Notice of Proposed Rulemaking, ET Docket No.
    03-122, (released June 4, 2003) ("U-NII NPRM").

[^2]: *See* 47 C.F.R. Part 15 Subpart E -- Unlicensed National
    Information Infrastructure Devices. U-NII devices are
    "\[i\]ntentional radiators operating in the frequency bands
    5.15-5.35 GHz and 5.725-5.825 GHz that use wideband digital
    modulation techniques and provide a wide array of high data rate
    mobile and fixed communications for individuals, businesses, and
    institutions." 47 C.F.R. §15.403(i).

[^3]: The rules being proposing are those deemed necessary to protect
    incumbent users from interference. Industry standards being
    developed by the Institute for Electrical and Electronics Engineers
    (IEEE) or others may contain more detailed technical requirements.

[^4]: The U.S. Table of Frequency Allocations is set forth in Section
    2.106 of the Commission's Rules, 47 C.F.R. § 2.106.

[^5]: The Commission previously proposed primary Federal Government EESS
    (active) and SRS (active) allocations in the 5.25-5.35 GHz band and
    a Federal Government EESS (active) allocation in the 5.35-5.46 GHz
    band. *See Amendment of Parts 2, 25, and 87 of the Commission's
    Rules to Implement Decisions from World Radio Communication
    Conferences Concerning Frequency Bands Between 28 MHz and 36 GHz and
    to Otherwise Update the Rules in this Frequency Range*, Notice of
    Proposed Rulemaking, ET Docket No. 02-305, 17 F.C.C. Rcd. 19756
    (2003)*.*

[^6]: U-NII NPRM at ¶ 13.

[^7]: NTIA Special Publication 00-40, *Federal Radar Spectrum
    Requirements*, National Telecommunications and Information
    Administration, at 19 (May 2000).

[^8]: *Id.*

[^9]: To detect smaller targets narrower pulse widths are necessary. The
    bandwidth of a pulsed signal is related to the inverse of the pulse
    width (*e.g.*, smaller pulse widths result in wider emission
    bandwidths).

[^10]: *World Radiocommunication Conference 2003 (WRC-03) Final Acts
    (Provisional) as published on 4 July 2003*, International
    Telecommunication Union (Revision 1), at 28 (Sept. 4, 2003).

[^11]: U-NII NPRM at ¶ 14.

[^12]: *Id*. at ¶ 20.

[^13]: *Id.* at ¶ 22.

[^14]: *Id.* at ¶ 23.

[^15]: *Id*. at ¶ 25.

[^16]: *Id*. at ¶ 24.

[^17]: *Id.*

[^18]: World Radio Conference Resolution 229 Resolves 7 (2003).

[^19]: U-NII NPRM at ¶ 26.

[^20]: *Id*. at ¶ 22.

[^21]: *Id*. at Appendix B.

[^22]: 1 NTIA Report 97-334, *Broadband Spectrum Survey at San Diego,
    California,* National Telecommunications and Information
    Administration (Dec. 1996); NTIA Report 97-336, *Broadband Spectrum
    Survey at Los Angeles, California* National Telecommunications and
    Information Administration (May 1997); NTIA Report 99-367,
    *Broadband Spectrum Survey at San Francisco, California* *May-June
    1995*, National Telecommunications and Information Administration
    (July 1999); NTIA Report 95-321, *Broadband Spectrum Survey at
    Denver, Colorado,* National Telecommunications and Information
    Administration (Sept. 1995).

[^23]: 1 *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*, Notice of Proposed Rulemaking, ET Docket No.
    03-122, (released June 4, 2003) ("U-NII NPRM").