**United States of America**

**DRAFT PROPOSAL FOR THE WORK OF THE CONFERENCE**

**Agenda Item 1.2**: to review and take action, as required, on No.
**5.134** and related Resolutions **517 (Rev.WRC**-**97)** and **537
(WRC**-**97)** and Recommendations **515 (Rev.WRC**-**97)**, **517
(HFBC**-**87)**, **519 (WARC**-**92)** and Appendix **11**, in the light
of the studies and actions set out therein, having particular regard to
the advancement of new modulation techniques, including digital
techniques, capable of providing an optimum balance between sound
quality, bandwidth and circuit reliability in the use of the HF bands
allocated to the broadcasting service*.*

**Background Information**: This agenda item is directed towards the
operational use of digital modulation techniques for broadcasting in the
HF bands. There has been sufficient progress in ITU-R SG 6, so that the
digital modulation techniques to be considered under this agenda item
are limited to just the digital modulation techniques recommended in
Recommendation ITU-R **BS.1514**. WRC-2003 will therefore be fully
competent to set any necessary conditions for introducing these
digitally modulated emissions to the HF bands allocated to broadcasting.

The collection of all the articles, resolutions and recommendations
listed in the agenda item text are the ones that will need to be
reviewed for suppression or modification in the light of the progress
that has been made in the intervening years for digital modulation use
in the HF broadcasting bands. To complete the overall need, some
additions will have to be made. The suppressions, modifications and
additions that are incorporated in the U.S. proposal form an integrated
package that deals in an efficient manner with all the aspects of the
consequent needs connected with this non-allocation agenda item. By and
large, the specific wording of these suggested changes are those that
were developed within the ITU-R's Study Group 6 at its WP6E meetings
during 2001.

Recommendation ITU-R **BS.1514,** mentioned above, is a system
recommendation, wherein the acceptable digital modulation techniques are
recorded. The development and testing of this modulation, including its
various "modes" associated with different levels of robustness and audio
quality, has brought the techniques close to consumer product status. It
is expected that by the end of 2003, or not long thereafter, there will
be on the market receivers that include a HF digital capability. In
addition, modern HF transmitters can accept these digital signal inputs.

It is because of this progress that this agenda item and this proposal
exist \-- and, without diminishing broadcaster and listener access to
traditional amplitude modulation, simply permits digital modulation in
the mix of acceptable and available listening.

Furthermore, since the introduction of digital modulation for
operational use is two years or so from 2002, the proposed modifications
to existing articles, resolutions and recommendations treat all HF
broadcasting bands on an equal footing. There is no longer any
compelling reason to separate the conditions of use of the "WARC-92"
bands from the other HF broadcasting bands. The solution proposed is to
modify Article footnote **5.134** so that any ITU-R approved amplitude
modulation or digital modulation can be broadcast in the "WARC-92" bands
after 1 April 2007. Before that time, the proposal is not to permit
broadcasting in these bands, other than on a non-harmful interference
basis (as is the current situation using **4.4**).

Three resolutions and recommendations are proposed to be suppressed
since they are no longer relevant. They are noted at the end of the
proposal, with appropriate reasons.

**Proposals:**

**USA/ /1 MOD**

**RESOLUTION 517 [(Rev.WRC-03)~~(~~]{.underline}~~Rev.WRC-97)~~**

[Introduction of digitally modulated and single-sideband
emissions]{.underline}~~Transition from double-sideband to
single-sideband or other spectrum-efficient modulation techniques~~ in
the high-frequency bands between 5 900 KHz and 26 100 KHz allocated to
the broadcasting service

The World Radiocommunication Conference (Caracas,
~~1997~~[2003]{.underline}),

considering

*a)* that [digital techniques are being introduced into many existing
services]{.underline} ~~the high-frequency (HF) bands allocated to the
broadcasting service between 5 900 kHz and 26 100 kHz are severely
congested~~;

*b)* that [digital and]{.underline} single-sideband (SSB) techniques
allow more ~~efficient~~ [effective]{.underline} utilization of the
frequency spectrum than double-sideband (DSB) techniques;

*c)* that [digital and]{.underline} SSB techniques enable reception
quality to be improved;

~~*d)* that recommendation 515(Rev.WRC-97) encourages the acceleration
design and manufacture of SSM transmitters and receivers;~~

*~~e~~[d]{.underline})* Appendix **11** concerning the [digital
and]{.underline} SSB system specification[s]{.underline} in the HF
broadcasting services;

~~*f)* that rapid developments are taking place in digital sound
broadcasting technologies;~~

[*e)* that ITU-R in its Recommendation ITU-R **BS.1514** has recommended
system characteristics for digital sound broadcasts in the broadcast
bands below 30 MHz]{.underline}~~;~~

*~~g~~[f]{.underline})* that digital modulation techniques are expected
to provide the means to achieve the optimum balance between sound
quality, circuit reliability and bandwidth;

*~~h~~[g]{.underline})* that digitally modulated emissions can, in
general, provide more efficient coverage than amplitude-modulated
transmissions by using fewer simultaneous frequencies and less power;

*[h]{.underline})* that it is economically attractive, using current
technology, to convert [modern]{.underline} conventional DSB
broadcasting systems to ~~SSB~~ [digital]{.underline} operation [in
accordance with *considering d)* above]{.underline};

*[j]{.underline})* that some DSB transmitters have been used with
digital modulation techniques without transmitter modifications;

l)  ~~that the lifetime of a receiver is of the order of ten years;~~

~~m)~~*[k)]{.underline}* that ITU-R is carrying out ~~urgent~~
[further]{.underline} studies on the development of broadcasting using
digital[ly]{.underline} modulat[ed]{.underline}~~ion~~ emissions in the
bands allocated to the broadcasting service below 30
MHz~~;~~[,]{.underline}

~~n) that other spectrum-efficient modulation techniques may be
developed in the future,~~

> resolves

1 that the [early introduction of digitally modulated emissions
as]{.underline} ~~procedure in the Annex to this Resolution shall be
used for the purpose of ensuring an orderly transition from DSB to SSB
or other spectrum-efficient modulation techniques~~ recommended by ITU-R
in the HF bands between 5 900 kHz and 26 100 kHz allocated to the
broadcasting service [is to be encouraged]{.underline};

2 that [digitally modulated and SSB emissions shall comply with the
characteristics specified in Appendix **11**]{.underline};

3 that whenever an administration replaces a DSB emission by an emission
using digital or SSB modulation techniques, it shall ensure that the
level of interference is not greater than that caused by the original
DSB emission, and shall use RF Protection values specified in
Recommendations **DAB [(WRC-03)]{.underline}** [and **517 (Rev.
WRC-03)**;]{.underline}

~~2~~[4]{.underline} that the ~~final date for the cessation~~
[continued use]{.underline} of DSB shall be periodically reviewed by
[a]{.underline} competent future world radiocommunication conference in
the light of the latest available complete statistics on the [capability
of administrations to introduce digital systems]{.underline} ~~worldwide
distribution of SSB and other spectrum-efficient modulation technique
transmitters and receivers, as called for in Resolution **537
(WRC-97)**,~~

instructs the Director of the Radiocommunication Bureau

to compile and maintain the statistics referred to in *resolves*
~~2~~[4]{.underline}, to make these statistics available to
administrations and to submit summaries thereof to a competent future
world radiocommunication conference~~s~~,

invites ITU-R

to continue its studies on digital techniques in HF broadcasting ~~as a
matter of urgency~~ with a view to assist in the development of this
technology for future use,

invites administrations

[1]{.underline} to assist the Director of the Radiocommunication Bureau
by providing the relevant statistical data and to participate in ITU-R
studies on matters relating to the development and introduction of
digitally modulated [emissions]{.underline} ~~transmissions~~ in the HF
bands between 5 900 kHz and 26 100 kHz allocated to the broadcasting
service~~.~~[;]{.underline}

[2 to bring to the notice of transmitter and receiver manufacturers the
most recent results of relevant ITU-R studies on spectrum-efficient
modulation techniques suitable for use at HF as well as the information
referred to in considerings *d)* and *e).*]{.underline}

**Reasons:** The changes to this resolution reflect the introduction of
digital and SSB emissions and the consequent need to protect DSB
emissions from digital and single sideband emissions, and vice versa.
The introduction of digital emissions does not substitute for single
sideband emission use. The resolution has been modified so that both are
considered on an equal regulatory footing. Several modifications made in
the *considerings* are a consequence of digital modulation development
for HF broadcasting since WRC-97.

USA/ /2 SUP

**ANNEX TO RESOLUTION 517 (Rev.WRC-97)**

**Reasons**: Due to the modifications to Resolution 517 related to the
introduction of digital and SSB emissions and deletion of the
requirement of the transition procedures, this annex is no longer
needed. This annex deals with a previous idea that all DSB would cease
after 2015. The complete package with regard to this agenda item
considers that this concept of cessation of one of the approved
modulation methods should be considered by a future competent
conference; that it is unrealistic to consider ceasing a particular type
of modulation without any concern for the listener and broadcaster
market 12 years after WRC-03.

###  {#section .Heading_b}

USA/ /3 MOD

APPENDIX 11

[System specifications for]{.underline} Double-Sideband (DSB), ~~and~~
Single-Sideband (SSB) [and Digitally Modulated Emissions]{.underline}
~~System Specifications~~ in the HF Broadcasting Service

**Reasons:** Updating the appendix title to reflect the proposed use.

**USA/ /4 [NOC]{.underline}**

Double-sideband system (DSB)

**Reasons**: The current text is adequate as written.

**PART B - Single-sideband system (SSB)**

1 System parameters

### USA/ /5 MOD {#usa-5-mod .Heading_b}

## 1.1 Channel spacing

[In a mixed DSB, SSB and Digital environment]{.underline} ~~During the
transition period~~ (see Resolution **517 ([Rev. WRC-03]{.underline}
~~HFBC-87~~)**), the channel spacing shall be 10 kHz. In the interest of
spectrum conservation, ~~during the transition period,~~ it is also
permissible to interleave SSB emissions midway between two adjacent DSB
channels, i.e., with 5 kHz separation between carrier frequencies,
provided that the interleaved emission is not to the same geographical
area as either of the emissions between which it is interleaved.

[In an all inclusive SSB environment,]{.underline} ~~After the end of
the transition period~~ the channel spacing and carrier frequency
separation shall be 5 kHz.

**Reasons**: Updating this text to reflect digital and SSB use and
deleting text concerning the transition period. No change in the carrier
reduction levels.

USA/ /6 MOD

6.  Carrier reduction (relative to peak envelope power)

[In a mixed DSB, SSB and Digital environment]{.underline} ~~During the
transition period~~ the carrier reduction shall be 6 dB to allow SSB
emissions to be received by conventional DSB receivers with envelope
detection without significant deterioration of the reception quality.

[In an all inclusive SSB environment]{.underline} ~~At the end of the
transition period~~, the carrier reduction shall be 12 dB.

**Reasons:** Updating this text to reflect digital and SSB use and
deleting text concerning the transition period. No change in the carrier
reduction levels.

USA/ /7 ADD

PART C - Digital system

1 System parameters

**1.1 Channel spacing**

The initial spacing for digitally modulated emissions use shall be 10
kHz. However, interleaved channels with a separation of 5 kHz may be
used in accordance with the appropriate protection criteria appearing in
Recommendation **DAB (WRC-03)**, provided that the interleaved emission
is not to the same geographical area as either of the emissions between
which it is interleaved.

1.2 Channel utilisation

Channels using digitally modulated emissions may be commingled with
analogue emissions in the same HFBC band provided the protection to the
analogue emissions is at least as great as that which currently is in
force with analogue-to-analogue protection. To accomplish this may
require that the digital spectral power density (and total power) be
lower by several dB than is currently used for the same emission circuit
using either DSB or SSB emissions.

**2 Emission characteristics**

**2.1 Bandwidth and centre frequency**

A full digitally modulated emission will have a 10 kHz bandwidth with
its centre frequency at any of the 5 kHz possibilities within the HFBC
bands.

There are "simulcast" modes, which are a combination of analogue and
digital emissions of the same programme in the same channel, that may
use a digital emission of 5 kHz or 10 kHz bandwidth, next to either a 5
kHz or 10 kHz analogue emission. In all cases of this type, the 5 kHz
interleaved raster used in HFBC shall be adhered to in placing the
emission within the HFBC bands.

2.2 Frequency tolerance

To be entered after WP6E determines the values at its September 2002
meeting.

2.3 Audio frequency band

Digital source coding within a 10 kHz bandwidth, taking account of the
need for various levels of error avoidance, detection and correction
coding emission mitigation, can range from the equivalent of monophonic
FM (approximately 15 kHz) to low level speech codec performance of the
order of 3 kHz. The choice of audio quality is connected to the needs of
the broadcaster/listener, and includes such characteristics to consider
as the propagation channel conditions expected. There is no single
specification, only the upper and lower bounds noted in this paragraph.

2.4 Modulation

Quadrature amplitude modulation (QAM) with Orthogonal frequency division
multiplexing (OFDM) shall be used. 64 QAM is feasible under many
propagation conditions; factors of ½, ¼ and perhaps 1/8 of this are
specified for use when needed.

**Reasons**: Part C is added to address the requirements of digital
systems. Specific channelization values, audio frequency bandwidths and
"modes" of digital modulation conform to ITU-R system Recommendation
**BS.1514**.

**USA/ /8 ADD**

**DRAFT RECOMMENDATION DAB (WRC-03)**

RF protection ratios associated with digitally modulated emissions in
the\
HF bands allocated exclusively to the broadcasting service

The World Radiocommunication Conference (Caracas, 2003),

considering

*a)* that this Conference has resolved to encourage the introduction of
digitally modulated emissions in the high frequency broadcast bands
allocated exclusively to the broadcasting service;

*b)* that the current use of the spectrum is based on the use of
double-sideband (DSB) emissions;

*c)* that RF co-channel and adjacent channel protection ratios are among
the fundamental parameters when determining compatibility;

d*)* that this Conference has adopted Resolution **517 (Rev. WRC-03)**
relating to the introduction of digitally modulated emissions in the HF
bands allocated exclusively to the broadcasting service;

*e)* that Part C of Appendix **11** contains digital system
specifications that refer to this recommendation for matters dealing
with appropriate protection ratios,

recommends

**1** that in the application of Article **12**, the protection ratios
specified in the Annex to this Recommendation be used for all those
cases where digitally modulated emissions operate in the same bands as
double-sideband analogue emissions.

### Reasons: This resolution provides protection ratios associated with digital emissions in the same manner as that of Recommendation 517, originally from HFBC-87, which deals with SSB and DSB only. It, along with its annex, specifies the levels of protection required both to protect the amplitude modulation transmissions from digital modulation emissions, digital modulation emissions from other digital modulation emissions, and digital modulation emissions from amplitude modulation emissions. {#reasons-this-resolution-provides-protection-ratios-associated-with-digital-emissions-in-the-same-manner-as-that-of-recommendation-517-originally-from-hfbc-87-which-deals-with-ssb-and-dsb-only.-it-along-with-its-annex-specifies-the-levels-of-protection-required-both-to-protect-the-amplitude-modulation-transmissions-from-digital-modulation-emissions-digital-modulation-emissions-from-other-digital-modulation-emissions-and-digital-modulation-emissions-from-amplitude-modulation-emissions. .Heading_b}

USA/ /9 ADD

**ANNEX TO RECOMMENDATION DAB (WRC-03)**

RF protection ratio values

1.  In accordance with Resolution **517 (Rev. WRC-03)** digital
    modulation may be used in any of the HF bands allocated exclusively
    to the broadcasting service. This accommodation has to be made with
    the appropriate amounts of protection given to both analogue and
    digital emissions. RF protection ratios are part of the overall
    regulation of these emissions. Their values appear in the table in
    this annex.

2.  The table consists of RF protection ratios for co-channel and
    adjacent channel conditions. The independent variable in the table
    is the centre frequency separation in kHz of any pair of emissions,
    wanted vs. unwanted. The ratio data are in decibels.

3.  The digital modulation governing these protection ratios is that
    which appears in summary in Part C of Appendix **11**, as revised at
    this conference, and the analogue modulation is double-sideband
    modulation or single sideband modulation as summarized in Parts A
    and B, respectively, of the same Appendix.

Protection Ratio Table

+-----------+------+---+-------+--------+--------+---------+--------+
| **Wanted  | **Ot |   | **C   |        |        |         |        |
| signal**  | her\ |   | entre |        |        |         |        |
|           | sign |   | freq  |        |        |         |        |
|           | al** |   | uency |        |        |         |        |
|           |      |   | separ |        |        |         |        |
|           |      |   | ation |        |        |         |        |
|           |      |   | (k    |        |        |         |        |
|           |      |   | Hz)** |        |        |         |        |
+-----------+------+---+-------+--------+--------+---------+--------+
|           |      |   |       |        |        |         |        |
+-----------+------+---+-------+--------+--------+---------+--------+
|           |      |   | 0     | 5      | 10     | 15      | 20     |
+-----------+------+---+-------+--------+--------+---------+--------+
| **DSB**   | **D  | ^ | 6     | 3      | -31    | -42     | -48    |
|           | igit | 1 |       |        |        |         |        |
|           | al** | ) |       |        |        |         |        |
|           |      | ^ |       |        |        |         |        |
+-----------+------+---+-------+--------+--------+---------+--------+
| **        | **D  | ^ | 8     | 2      | -31    | -38     | -40    |
| Digital** | SB** | 2 |       |        |        |         |        |
|           |      | ) |       |        |        |         |        |
|           |      | ^ |       |        |        |         |        |
+-----------+------+---+-------+--------+--------+---------+--------+
| **        | **D  | ^ | 17    | 12     | -35    | -39     | -44    |
| Digital** | igit | 2 |       |        |        |         |        |
|           | al** | ) |       |        |        |         |        |
|           |      | ^ |       |        |        |         |        |
+-----------+------+---+-------+--------+--------+---------+--------+
| ###       | **D  | ^ | \-    | \-     | \-     | \-      | \-     |
| ##### SSB | igit | 3 |       |        |        |         |        |
|           | al** | ) |       |        |        |         |        |
|           |      | ^ |       |        |        |         |        |
+-----------+------+---+-------+--------+--------+---------+--------+
| Digital   | **S  | ^ | \-    | \-     | \-     | \-      | \-     |
|           | SB** | 3 |       |        |        |         |        |
|           |      | ) |       |        |        |         |        |
|           |      | ^ |       |        |        |         |        |
+-----------+------+---+-------+--------+--------+---------+--------+

Notes:

> ^1)^ Values relative to the DSB/DSB co-channel RF protection ratio

2)  Values for a BER of 10^-4^

3)  Values for SSB into digital and digital into SSB will be supplied
    from the TG6/7 meeting to be held in September 2002.

**Reasons**: This annex provides the appropriate amounts of protection
given to both analogue and digital emissions and supports the text of
DRAFT RECOMMENDATION **DAB (WRC-03)**.

USA/ /10 MOD

**RECOMMENDATION 517 (**~~HFBC-87~~**[Rev.WRC-03]{.underline})**

~~Relative~~ RF protection ratio values for single-sideband (SSB)
emissions in the HF bands allocated exclusively to the broadcasting
service

The World ~~Administrative Radio~~ [Radiocommunication]{.underline}
Conference ~~for the Planning of the HF Bands Allocated to the
Broadcasting Service~~ ([Caracas, 2003]{.underline} ~~1987~~),

considering

*a)* that [WRC-97]{.underline} ~~the Conference has~~ adopted [Article
**12** as the seasonal]{.underline} ~~a method for the~~ planning
[procedure for]{.underline} ~~of~~ the HF bands allocated exclusively to
the broadcasting service;

*b)*that this ~~method~~ [procedure]{.underline} is based
[principally]{.underline} on the use of double-sideband (DSB) emissions;

*c)* that the RF co-channel protection ratio is one of the fundamental
planning parameters;

*d)* that ~~the~~ [this]{.underline} Conference has adopted Resolution
**517 [(Rev. WRC-03)]{.underline}** relating to the ~~transition~~
[introduction of digitally modulated and]{.underline} ~~from DSB to~~
SSB emissions in the HF bands allocated exclusively to the broadcasting
service ~~and Recommendation 515 relating to the introduction of
transmitters and receivers capable of both DSB and SSB modes of
operation~~;

*e)* that the SSB system characteristics for HF broadcasting are
contained in Appendix **11**;

~~*f)* that, however, due to their provisional nature, the values of the
relative RF protection ratio to be applied for all relevant combinations
of wanted and unwanted DSB and SSB emissions have not been included in
the Appendix mentioned in considering e);~~

*~~g~~[f]{.underline})* that ~~preliminary~~ studies have shown that SSB
emissions may require a lower RF co‑channel protection ratio for the
same reception quality;

~~*h)* Resolution 514 (HFBC-87)~~[^1] ~~relating to the procedure to be
applied by the Radio Regulations Board and the Bureau in the revision of
relevant parts of their Technical Standards used for HF broadcasting,~~

recommends

that, ~~subject to the procedure to be applied by the Radio Regulations
Board and the Bureau in the revision of relevant parts of their
Technical Standards used for HF broadcasting given in Resolution 514
(HFBC-87)\*,~~ the values of relative RF protection ratio given in the
Annex to this Recommendation be used by the Bureau in its [application
of Article **12**]{.underline} ~~Technical Standards~~ relating to SSB
[and DSB]{.underline} emissions in the HF bands allocated exclusively to
the broadcasting service,

~~invites the ITU-R~~

~~to continue to study the values of relative RF protection ratio for
the different cases and frequency separations covered in the Annex to
this Recommendation,~~

~~and recommends administrations~~

~~to participate actively in these studies.~~

**Reasons**: This recommendation has been modified to reflect the
introduction of digital emissions. No substantive changes were made in
the protection ration values with SSB vs. DSB amplitude modulation.

**USA/ /11 MOD**

**ANNEX TO RECOMMENDATION 517
(**~~HFBC-87~~**[Rev.WRC-03]{.underline})**

~~Relative~~ RF protection ratio values

1 The values of ~~relative~~ RF protection ratio given in the table
should be used whenever SSB emissions in conformity with the
specification in Appendix **11** are involved in the use of the HF bands
allocated exclusively to the broadcasting service.

~~2 The values given refer to the case of co-channel DSB wanted and
unwanted signals for the same reception quality.~~

~~3~~[2]{.underline} For the reception of DSB and SSB (6 dB carrier
reduction relative to peak envelope power) wanted signals, a
conventional DSB receiver with envelope detection designed for a channel
spacing of 10 kHz is assumed.

~~4~~[3]{.underline} For the reception of an SSB wanted signal (12 dB
carrier reduction relative to peak envelope power), the reference
receiver as specified in Appendix **11**, Part B, Section 3, is assumed.

~~5~~[4]{.underline} SSB signals with 6 dB carrier reduction relative to
peak envelope power assume equivalent sideband power as specified in
Appendix **11**, Part B, § 1.2.

~~6~~[5]{.underline} The figures for case 2 in the following table
relate to a situation where the centre frequency of the intermediate
frequency pass-band of the DSB receiver is tuned to the carrier
frequency of the wanted SSB signal. If this is not the case, the value
for a difference of +5 kHz may increase to --1 dB.\]

**~~Relative~~ RF protection ratio values with reference to the
co-channel RF protection\
ratio for DSB wanted and unwanted signals (dB)^1^ for use in the HF
bands\
allocated exclusively to the broadcasting service**

1.  Frequency separation ∆*f* less than --20 kHz, as well as ∆*f*
    greater than 20 kHz, need not be considered.

**Reasons**: Minor text changes were made to update the annex from
**HFBC-87**. No changes were made in the DSB vs. SSB table of protection
ratios.

USA/ /12 MOD

**5.134** The ~~use of the~~ bands 5 900-5 950 kHz, 7 300-7 350 kHz,
9 400-9 500 kHz, 11 600‑11 650 kHz, 12 050-12 100 kHz,
13 570-13 600 kHz, 13 800-13 870 kHz, 15 600‑15 800 kHz, 17 480-17 550
kHz and 18 900-19 020 kHz ~~by~~[are allocated to]{.underline} the
broadcasting service [on a primary basis as from 1 April
2007.]{.underline}~~is limited to single sideband emissions with the
characteristics specified in Appendix 11 or to any other spectrum
efficient modulation techniques recommended by ITU-R. Access to these
bands shall be subject to the decisions of a competent conference.~~

**Reasons**: The proposed modification provides a simple unambiguous
regulatory environment for the use of the WARC-92 extension bands both
before and after the envisaged implementation date of 1 April 2007.
Before the 01/04/07 date, there is no change: in other words, the bands
are not allocated to HFBC. After that date, broadcasters can choose any
modulation means that has ITU-R approval, such as the digital modulation
described in ITU-R Recommendation **BS.1514** and the SSB and DSB
amplitude modulations noted in Article **11**.

**USA/ /13 SUP**

RESOLUTION 537 (WRC-97)

**Reasons**: The survey mentioned in the resolution on transmitter and
receiver statistics related to SSB has been completed, and submitted by
the BR for WRC-2000, as requested from WRC-97. Therefore, there is no
need to carry forward this resolution. The associated Recommendation
**515 (Rev.WRC-97)** is also proposed for suppression as detailed below.

**USA/ /14 SUP**

RECOMMENDATION 515 (Rev.WRC-97)

**Reasons**: With the adoption of this Recommendation **BS.1514** and
the fact that IEC has been informed of this development, Recommendation
**515 (Rev.WRC-97)** can be suppressed.

**USA/ /15 SUP**

RECOMMENDATION 519 (WARC-92)

**Reasons:** This Recommendation, from WARC-92, considers the
possibility of advancing the date of cessation of DSB. In the light of
broadcasting needs in HF, this is totally unrealistic. Thus, there is
concern within many Administrations, expressed on many occasions at
WRC‑97, that the introduction of SSB into HF Broadcasting (and now
digital modulation) should not restrict the ability of administrations
to continue with their existing DSB transmissions for the foreseeable
future and that at this point in time it is inappropriate to specify a
cessation of DSB in favour of SSB in the year 2015. It is also evident
from information presented at WRC-2000 by the Director that the interest
in SSB within HF Broadcasting is virtually non-existent. This
Recommendation should therefore be suppressed.

**USA/ /16 MOD**

ARTICLE 23.12

~~Double-sideband and single side-band t~~[T]{.underline}ransmitting
stations operating in the HF bands allocated exclusively to the
Broadcasting Service shall meet the system specifications contained in
Appendix 11.

**Reasons:** A consequential change that reflects the change in Appendix
**11** that has added digital modulation to the acceptable modulation
methods.

[^1]: ^\*^ ~~This Resolution was abrogated by WRC-97.~~