IEC 60728-10:2001

Cabled distribution systems for television and sound signals - Part 10: System performance of return path

Deals with the transparent return path of cable networks operated in the frequency range 5 MHz to 65 MHz. Lays down basic methods of measurement for signals used in the return path, in order to assess the performance and performance limits.

General Information

• Status: Published
• Publication Date: 06-Mar-2001
• ICS: 33.060.40 - Cabled distribution systems
• Technical Committee: TC 100 - Audio, video and multimedia systems and equipment
• Current Stage: DELPUB - Deleted Publication
• Completion Date: 27-Jun-2005

Relations

• Revised: IEC 60728-10:2005 - Cable networks for television signals, sound signals and interactive services - Part 10: System performance of return paths
• Effective Date: 05-Sep-2023

Standards Content (Sample)

INTERNATIONAL IEC
STANDARD
60728-10
First edition
2001-03
Cabled distribution systems for television
and sound signals –
Part 10:
System performance of return path

Reference number
Publication numbering
As from 1 January 1997 all IEC publications are issued with a designation in the
60000 series. For example, IEC 34-1 is now referred to as IEC 60034-1.

Consolidated editions
The IEC is now publishing consolidated versions of its publications. For example,

edition numbers 1.0, 1.1 and 1.2 refer, respectively, to the base publication, the
base publication incorporating amendment 1 and the base publication incorporating
amendments 1 and 2.
Further information on IEC publications
The technical content of IEC publications is kept under constant review by the IEC,
thus ensuring that the content reflects current technology. Information relating to
this publication, including its validity, is available in the IEC Catalogue of
publications (see below) in addition to new editions, amendments and corrigenda.
Information on the subjects under consideration and work in progress undertaken
by the technical committee which has prepared this publication, as well as the list
of publications issued, is also available from the following:
• IEC Web Site (www.iec.ch)
• Catalogue of IEC publications
The on-line catalogue on the IEC web site (www.iec.ch/catlg-e.htm) enables
you to search by a variety of criteria including text searches, technical
committees and date of publication. On-line information is also available on
recently issued publications, withdrawn and replaced publications, as well as
corrigenda.
• IEC Just Published
This summary of recently issued publications (www.iec.ch/JP.htm) is also
available by email. Please contact the Customer Service Centre (see below) for
further information.
• Customer Service Centre
If you have any questions regarding this publication or need further assistance,
please contact the Customer Service Centre:
Email: [e-mail]
Tel: [phone]
Fax: [phone]
INTERNATIONAL IEC
STANDARD
60728-10
First edition
2001-03
Cabled distribution systems for television
and sound signals –
Part 10:
System performance of return path
:
 IEC 2001  Copyright - all rights reserved
No part of this publication may be reproduced or utilized in any form or by any means, electronic or
mechanical, including photocopying and microfilm, without permission in writing from the publisher.
International Electrotechnical Commission 3, rue de Varembé Geneva, Switzerland
Telefax: [phone] e-mail: [e-mail] IEC web site http://www.iec.ch
Commission Electrotechnique Internationale
PRICE CODE
U
International Electrotechnical Commission
For price, see current catalogue

– 2 – 60728-10  IEC:2001(E)
CONTENTS
Page
FOREWORD .3

INTRODUCTION.4

Clause
1 Scope.5

2 Normative references .6

3 Terms, definitions, symbols and abbreviations .7

3.1 Terms and definitions .7

3.2 Symbols .9
3.3 Abbreviations .9
4 Methods of measurement .10
4.1 Set-up of the network .10
4.2 Measurement of signal level .11
4.3 Measurement of amplitude response .13
4.4 Measurement of signal to noise ratio (S/N) .13
4.5 Measurement of multiple interference .14
4.6 Measurement of impulse noise .15
4.7 Measurement of echo ratio .16
4.8 Measurement of group delay variation .17
4.9 Measurement of frequency error .17
4.10 Measurement of bit error rate (BER) .18
5 System performance requirements .20
5.1 Introduction .20
5.2 Analogue parameters influencing system performance.21
5.3 General requirements.22
5.4 Specific system performance requirements.22
6 System performance recommendations .23
6.1 Proposal for the use of the return path bandwidth .23
Annex A (informative) System performance requirements for different modulation techniques.25
Annex B (normative) Correction factors for noise.26
Bibliography.28

Figure 1 – Reference points of an active return path system (example).5
Figure 2 – Procedure for set-up and adjustment of the upstream system .11
Figure 3 – Arrangement of test equipment for measurement of echo ratio.17
Figure 4 – Test set-up for frequency stability measurement .18
Figure 5 – Principle of BER measurement .18
Figure 6 – Upstream signals affecting downstream signals .20
Figure 7 – Downstream signals affecting upstream signals .21
Figure 8 – Upstream signals of service 1 affecting upstream signals of a different service
(e.g. service 2).21
Figure 9 – Upstream signals of a specific service (e.g. service 2) affecting upstream signals
of the same service.21
Figure 10 – Identification of the most common sub-bands within the return path band with
limited transmission quality .24
Figure B.1 – Noise correction factor (CF) versus measured level difference (D) .27
dB dB
60728-10  IEC:2001(E) – 3 –
INTERNATIONAL ELECTROTECHNICAL COMMISSION

____________
CABLED DISTRIBUTION SYSTEMS FOR TELEVISION

AND SOUND SIGNALS –
Part 10: System performance of return path

FOREWORD
1) The IEC (International Electrotechnical Commission) is a worldwide organization for standardization comprising all
national electrotechnical committees (IEC National Committees). The object of the IEC is to promote international
co-operation on all questions concerning standardization in the electrical and electronic fields. To this end and in
addition to other activities, the IEC publishes International Standards. Their preparation is entrusted to technical
committees; any IEC National Committee interested in the subject dealt with may participate in this preparatory
work. International, governmental and non-governmental organizations liaising with the IEC also participate in this
preparation. The IEC collaborates closely with the International Organization for Standardization (ISO) in
accordance with conditions determined by agreement between the two organizations.
2) The formal decisions or agreements of the IEC on technical matters express, as nearly as possible, an international
consensus of opinion on the relevant subjects since each technical committee has representation from all
interested National Committees.
3) The documents produced have the form of recommendations for international use and are published in the form of
standards, technical specifications, technical reports or guides and they are accepted by the National Committees
in that sense.
4) In order to promote international unification, IEC National Committees undertake to apply IEC International
Standards transparently to the maximum extent possible in their national and regional standards. Any divergence
between the IEC Standard and the corresponding national or regional standard shall be clearly indicated in the
latter.
5) The IEC provides no marking procedure to indicate its approval and cannot be rendered responsible for any
equipment declared to be in conformity with one of its standards.
6) Attention is drawn to the possibility that some of the elements of this International Standard may be the subject of
patent rights. The IEC shall not be held responsible for identifying any or all such patent rights.
International Standard IEC 60728-10 has been prepared by TA 5: Cable networks for television
signals, sound signals and interactive services, of IEC technical committee 100: Audio, video and
multimedia systems and equipment.
The text of this standard is based on the following documents:
FDIS Report on voting
100/200/FDIS 100/224/RVD
Full information on the voting for the approval of this standard can be found in the report on voting

indicated in the above table.
This publication has been drafted in accordance with the ISO/IEC Directives, Part 3.
Annex A is for information only.
Annex B forms an integral part of this standard.
The committee has decided that the contents of this publication will remain unchanged until 2003.
At this date, the publication will be
reconfirmed;
withdrawn;
replaced by a revised edition, or
amended.
A bilingual version of this standard may be issued at a later date.

– 4 – 60728-10  IEC:2001(E)
INTRODUCTION
Standards of the IEC 60728 series deal with cable networks for television signals, sound signals

and interactive services including equipment for:

– head-end -reception, processing and distribution of television and sound signals and their

associated data signals;
– processing, interfacing and transmitting all kinds of signals for interactive services using all

applicable transmission media.

They apply to all kinds of networks such as:

– CATV-systems;
– MATV-systems and SMATV-systems;
– individual receiving systems and
– all kinds of equipment installed in such systems.
The extent of this standardization work is from the antennas and special signal source inputs to
the head-end or other interface points to the network up to the system outlet or, where no system
outlet exists, the terminal input.
The standardization of any user terminals (i.e. tuners, receivers, decoders, multimedia terminals,
etc.) is excluded.
60728-10  IEC:2001(E) – 5 –
CABLED DISTRIBUTION SYSTEMS FOR TELEVISION

AND SOUND SIGNALS –
Part 10: System performance of return path

1 Scope
This part of IEC 60728 deals with the transparent return path of cable networks operated in the
frequency range between 5 MHz and 65 MHz or parts thereof. Higher frequencies may be used in
fibre-based networks.
NOTE In addition, it is possible to use the frequency range from 0 MHz to 5 MHz for return path transmissions, for
example for NMS or other control, monitoring and signalling purposes. Applications below 5 MHz are not covered by
this standard.
An active return path typically carries only return signals. A passive return path can be used for
both return and forward signals.
This part of IEC 60728 lays down the basic methods of measurement for signals typically used in
the return path of cable networks in order to assess the performance of those signals and their
performance limits.
All requirements refer to the performance limits which have to be obtained between the reference
points (figure 1) of the return path system.
One reference point is the network termination close to the subscriber. It is the last point where all
forward and return signals are present and carried on the same cable. If no network termination
point exists, the reference point is the system outlet.
The other reference point is the input of the return signal receiver (or transceiver). At this point the
transparent signal path ends and beyond this point the signal is treated in a non-transparent way.
The return signal receiver can be situated at the head-end but can also be at the node of the
coaxial cell or at any other point of the network.
TV
O
E
Network termination
Reference point
IEC  330/01
Figure 1 – Reference points of an active return path system (example)

– 6 – 60728-10  IEC:2001(E)
In addition to the system performance requirements for the transparent return path, system

performance recommendations are laid down in this part of IEC 60728, for example for the overall

frequency allocation, for the use of specific modulation techniques for different interactive

multimedia services or for different sub-bands within the return path frequency range, etc.

Specific equipment inst
...