EN 62273-1:2007
(Main)Methods of measurement for radio transmitters - Part 1: Performance characteristics of terrestrial digital television transmitters
Methods of measurement for radio transmitters - Part 1: Performance characteristics of terrestrial digital television transmitters
gives the conditions for measuring the performance parameters of terrestrial digital transmitters and for facilitating the comparison of measurements which are carried out by different personnel. It contains details of specially selected methods for determining the most important performance parameters of digital transmitters. The measurement methods described apply to a limited number of performance parameters, i.e. those which can give rise to ambiguous interpretation due to the use of different methods and conditions. They are neither restrictive nor mandatory: measurements can be chosen for each particular case. If necessary, additional tests can be carried out but they shall comply with those standards which have been established by other study groups, subcommittees of the IEC or other international or suitably accredited organizations.
Messverfahren für Funksender - Teil 1: Übertragungseigenschaften von terrestrischen digitalen Fernsehsendern
Méthodes de mesure applicables aux émetteurs radioélectriques - Partie 1: Qualité de fonctionnement des émetteurs de télévision numérique terrestre
La CEI 62273-1:2007 définit les conditions permettant de mesurer les performances des émetteurs numériques terrestres et de faciliter la comparaison de mesures réalisées par différentes personnes. Elle détaille des méthodes plus particulièrement choisies pour déterminer les caractéristiques de performance principales des émetteurs numériques. Les méthodes de mesure décrites s'appliquent à un nombre limité de caractéristiques, comme par exemple, celles qui donneraient lieu à une interprétation ambiguë de par l'utilisation de différentes méthodes et conditions de mise en application. Elles ne sont ni restrictives, ni obligatoires: il est permis de choisir la méthode d'évaluation en fonction du cas se présentant. Il est envisageable de compléter les essais réalisés; dans ce cas, ils doivent respecter les normes établies par d'autres groupes d'étude, par des sous-comités de la CEI ou d'autres organismes internationaux ou accrédités. La présente version bilingue (2012-03) correspond à la version anglaise monolingue publiée en 2007-02.
Metode za meritve radijskih oddajnikov - 1. del: Karakteristike zmogljivosti prizemne digitalne televizije (IEC 62273-1:2007)
General Information
Standards Content (Sample)
SLOVENSKI STANDARD
01-december-2007
Metode za meritve radijskih oddajnikov – 1. del: Karakteristike zmogljivosti
prizemne digitalne televizije (IEC 62273-1:2007)
Methods of measurement for radio transmitters -- Part 1: Performance characteristics of
terrestrial digital television transmitters (IEC 62273-1:2007)
Messverfahren für Funksender -- Teil 1: Übertragungseigenschaften von terrestrischen
digitalen Fernsehsendern (IEC 62273-1:2007)
Méthodes de mesure applicables aux émetteurs radioélectriques -- Partie 1: Qualité de
fonctionnement des émetteurs de télévision numérique terrestre (IEC 62273-1:2007)
Ta slovenski standard je istoveten z: EN 62273-1:2007
ICS:
33.060.20 Sprejemna in oddajna Receiving and transmitting
oprema equipment
33.170 Televizijska in radijska Television and radio
difuzija broadcasting
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.
EUROPEAN STANDARD
EN 62273-1
NORME EUROPÉENNE
April 2007
EUROPÄISCHE NORM
ICS 33.060.20
English version
Methods of measurement for radio transmitters -
Part 1: Performance characteristics
of terrestrial digital television transmitters
(IEC 62273-1:2007)
Méthodes de mesure applicables Messverfahren für Funksender -
aux émetteurs radioélectriques - Teil 1: Übertragungseigenschaften
Partie 1: Qualité de fonctionnement von terrestrischen digitalen
des émetteurs de télévision Fernsehsendern
numérique terrestre (IEC 62273-1:2007)
(CEI 62273-1:2007)
This European Standard was approved by CENELEC on 2007-03-01. CENELEC members are bound to comply
with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this European Standard
the status of a national standard without any alteration.
Up-to-date lists and bibliographical references concerning such national standards may be obtained on
application to the Central Secretariat or to any CENELEC member.
This European Standard exists in three official versions (English, French, German). A version in any other
language made by translation under the responsibility of a CENELEC member into its own language and notified
to the Central Secretariat has the same status as the official versions.
CENELEC members are the national electrotechnical committees of Austria, Belgium, Bulgaria, Cyprus, the
Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia,
Lithuania, Luxembourg, Malta, the Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain,
Sweden, Switzerland and the United Kingdom.
CENELEC
European Committee for Electrotechnical Standardization
Comité Européen de Normalisation Electrotechnique
Europäisches Komitee für Elektrotechnische Normung
Central Secretariat: rue de Stassart 35, B - 1050 Brussels
© 2007 CENELEC - All rights of exploitation in any form and by any means reserved worldwide for CENELEC members.
Ref. No. EN 62273-1:2007 E
Foreword
The text of document 103/63/FDIS, future edition 1 of IEC 62273-1, prepared by IEC TC 103,
Transmitting equipment for radio communication, was submitted to the IEC-CENELEC parallel vote and
was approved by CENELEC as EN 62273-1 on 2007-03-01.
The following dates were fixed:
– latest date by which the EN has to be implemented
at national level by publication of an identical
national standard or by endorsement (dop) 2007-12-01
– latest date by which the national standards conflicting
with the EN have to be withdrawn (dow) 2010-03-01
Annex ZA has been added by CENELEC.
__________
Endorsement notice
The text of the International Standard IEC 62273-1:2007 was approved by CENELEC as a European
Standard without any modification.
In the official version, for Bibliography, the following note has to be added for the standard indicated:
IEC 60244-2 + NOTE Harmonized as HD 236.2 S1:1977 (not modified).
IEC 60244-2A
__________
- 3 - EN 62273-1:2007
Annex ZA
(normative)
Normative references to international publications
with their corresponding European publications
The following referenced documents are indispensable for the application of this document. For dated
references, only the edition cited applies. For undated references, the latest edition of the referenced
document (including any amendments) applies.
NOTE When an international publication has been modified by common modifications, indicated by (mod), the relevant EN/HD
applies.
Publication Year Title EN/HD Year
1) 2)
IEC 60215 - Safety requirements for radio transmitting EN 60215 1989
equipment
1) 2)
IEC 60244-1 - Methods of measurement for radio EN 60244-1 2000
transmitters -
Part 1: General characteristics for broadcast
transmitters
1)
ITU-R - Error correction, data framing, modulation - -
Recommendation and emission methods for digital terrestrial
BT.1306-3 telesision broadcasting
ITU-R 2004 Radio Regulations - -
1)
Undated reference.
2)
Valid edition at date of issue.
INTERNATIONAL IEC
STANDARD 62273-1
First edition
2007-02
Methods of measurement for radio transmitters –
Part 1:
Performance characteristics of terrestrial
digital television transmitters
© IEC 2007 ⎯ 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, PO Box 131, CH-1211 Geneva 20, Switzerland
Telephone: +41 22 919 02 11 Telefax: +41 22 919 03 00 E-mail: inmail@iec.ch Web: www.iec.ch
PRICE CODE
Commission Electrotechnique Internationale W
International Electrotechnical Commission
МеждународнаяЭлектротехническаяКомиссия
For price, see current catalogue
– 2 – 62273-1 © IEC:2007(E)
CONTENTS
FOREWORD.4
1 Scope.6
2 Normative references .6
3 Terms, definitions and abbreviations .7
4 General conditions of measurement .9
4.1 Temperature and humidity.9
4.2 Conditions for primary power supply.9
4.3 Output power.9
4.4 Test load .9
4.5 Auxiliary equipment .9
4.6 Test equipment and test signals .10
5 General characteristics.10
5.1 Frequency .10
5.2 Output power.11
5.3 Spurious domain emission.14
5.4 Out-of-band domain emission.14
5.5 Occupied bandwidth .15
5.6 Power consumption .16
6 Transmitted signal characteristics.16
6.1 Intermodulation (shoulders).16
6.2 Modulation error ration (MER) .17
6.3 Bit error ratio (BER) .17
6.4 Equivalent noise degradation .18
6.5 Phase noise .19
7 Protection against atmospheric discharge.20
8 Acoustic noise .20
9 Safety.20
Annex A (normative) Eye-height characteristics .21
Annex B (normative) Characteristic frequency .22
Annex C (normative) Frequency drift.25
Annex D (normative) Attenuation of the measuring coupler .26
Annex E (normative) Spurious emissions/out-of-band emissions.28
Annex F (normative) DVB-T shoulder attenuation measurement .32
Annex G (normative) Modulation error ratio (MER) measurement.36
Annex H (normative) Bit error rate (BER) measurement .38
Bibliography.39
62273-1 © IEC:2007(E) – 3 –
Figure 1 – Measuring set-up for output power .12
Figure 2 – Measuring set-up for spurious emission, out-of-band emission and
bandwidth .15
Figure A.1 – Transmitter eye diagram for jitter .21
Figure B.1 – Measurement.23
Figure B.2 – Frequency spectrum analysis.24
Figure D.1 – Measurement.26
Figure D.2 – Relative coupling .27
Figure D.3 – Coupling attenuation.27
Figure E.1 – Attenuation curve.29
Figure E.2 – Out-of-band and spurious emissions .30
Figure E.3 – Output filter.30
Figure E.4 – High-frequency spectrum .31
Figure E.5 – Superimpose curve .31
Figure F.1 – Measurement .32
Figure F.2 – Shoulder attenuation.33
Figure F.3 – Analyser setting .33
Figure F.4 – Measurement system of intermodulation .34
Figure F.5 – Measurement of intermodulation at the upper side of the channel .35
Figure G.1 – Measurement .36
Figure H.1 – Measurement.38
Table 1 – Measurement parameters for out-of-band emission .15
Table 2 – Measurement parameters for occupied bandwidth .16
Table 3 – Equivalent noise bandwidth .18
Table A.1 – Electrical characteristic specifications for ASI link .21
– 4 – 62273-1 © IEC:2007(E)
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
METHODS OF MEASUREMENT FOR RADIO TRANSMITTERS –
Part 1: Performance characteristics of terrestrial
digital television transmitters
FOREWORD
1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising
all national electrotechnical committees (IEC National Committees). The object of 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, IEC publishes International Standards, Technical Specifications,
Technical Reports, Publicly Available Specifications (PAS) and Guides (hereafter referred to as “IEC
Publication(s)”). 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. 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 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 IEC National Committees.
3) IEC Publications have the form of recommendations for international use and are accepted by IEC National
Committees in that sense. While all reasonable efforts are made to ensure that the technical content of IEC
Publications is accurate, IEC cannot be held responsible for the way in which they are used or for any
misinterpretation by any end user.
4) In order to promote international uniformity, IEC National Committees undertake to apply IEC Publications
transparently to the maximum extent possible in their national and regional publications. Any divergence
between any IEC Publication and the corresponding national or regional publication shall be clearly indicated in
the latter.
5) IEC provides no marking procedure to indicate its approval and cannot be rendered responsible for any
equipment declared to be in conformity with an IEC Publication.
6) All users should ensure that they have the latest edition of this publication.
7) No liability shall attach to IEC or its directors, employees, servants or agents including individual experts and
members of its technical committees and IEC National Committees for any personal injury, property damage or
other damage of any nature whatsoever, whether direct or indirect, or for costs (including legal fees) and
expenses arising out of the publication, use of, or reliance upon, this IEC Publication or any other IEC
Publications.
8) Attention is drawn to the Normative references cited in this publication. Use of the referenced publications is
indispensable for the correct application of this publication.
9) Attention is drawn to the possibility that some of the elements of this IEC Publication may be the subject of
patent rights. IEC shall not be held responsible for identifying any or all such patent rights.
International Standard IEC 62273-1 has been prepared by IEC technical committee 103:
Transmitting equipment for radio communication
The text of this standard is based on the following documents:
FDIS Report on voting
103/63/FDIS 103/65/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 2.
The list of all the publications of the IEC 62273 series, under the general title Methods of
measurement for radio transmitters, can be found on the IEC website.
62273-1 © IEC:2007(E) – 5 –
The committee has decided that the contents of this publication will remain unchanged until
the maintenance result date indicated on the IEC web site under "http://webstore.iec.ch" in
the data related to the specific publication. At this date, the publication will be
• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.
A bilingual edition of this document may be issued at a later date.
– 6 – 62273-1 © IEC:2007(E)
METHODS OF MEASUREMENT FOR RADIO TRANSMITTERS –
Part 1: Performance characteristics of terrestrial
digital television transmitters
1 Scope
This part of IEC 62273 gives the conditions for measuring the performance parameters of
terrestrial digital transmitters and for facilitating the comparison of measurements which are
carried out by different personnel. It contains details of specially selected methods for
determining the most important performance parameters of digital transmitters. The
measurement methods described apply to a limited number of performance parameters, i.e.
those which can give rise to ambiguous interpretation due to the use of different methods and
conditions. They are neither restrictive nor mandatory: measurements can be chosen for each
particular case. If necessary, additional tests can be carried out but they shall comply with
those standards which have been established by other study groups, subcommittees of the
IEC or other international or suitably accredited organizations.
No limits have been assigned to quantify acceptable ranges of performance parameters.
These are judged to be properly included in the technical specifications for individual
transmitters; however, the terms and the manner used to quantify them should ideally be
those described in a future IEC publication.
The measurement methods described in this standard are intended for type approval tests.
However they can equally well apply to acceptance tests measurements and quality control
tests either in factories or on site.
Test signals are used to measure performance parameters for both digital and analogue
terrestrial transmitters. Their electronic characteristics and their associated performance
parameters are widely understood. The test signals are measured after they have gone
through the transmitter equipment to determine if their degradation is within the required
quality criteria.
This standard does not go into any detail regarding MPEG 2 signals or DVB processes nor
does it deal with digital signal processing.
2 Normative references
The following referenced documents are indispensable for the application of this document.
For dated references, only the edition cited applies. For undated references, the latest edition
of the referenced document (including any amendments) applies.
IEC 60215, Safety requirements for radio transmitting equipment
IEC 60244-1, Methods of measurement for radio transmitters – Part 1: General characteristics
for broadcast transmitters
ITU-R Recommendation BT.1306-3, Error correction, data framing, modulation and emission
methods for digital terrestrial television broadcasting.
ITU-R:2004, Radio Regulations
62273-1 © IEC:2007(E) – 7 –
ETS 30 0744, Digital video broadcasting – Framing structure, channel coding and modulation
for digital terrestrial television.
ETSI 101 290, Digital video broadcasting (DVB) – Measurement guidelines for DVB system
3 Terms, definitions and abbreviations
For the purposes of this document, the following terms, definitions and abbreviations apply.
3.1
ASI
Asynchronous Serial Interface
3.2
ATSC
Advanced Television Systems Committee
3.3
BER
Bit Error Ratio
3.4
BW
Bandwidth
3.5
C/N
Ratio of the r.f. or i.f. carrier power to noise power
3.6
COFDM
Coded Orthogonal Frequency Division Multiplex
3.7
CPE
Common Phase Error
3.8
DVB
Digital Video Broadcasting
3.9
DVB-T
Digital Video Broadcasting baseline system for digital terrestrial television
3.10
END
Equivalent Noise Degradation
3.11
ETS
European Telecommunication Standard
3.12
ICI
Inter Carrier Interference
– 8 – 62273-1 © IEC:2007(E)
3.13
IEC
International Electrotechnical Commission
3.14
ISDB-T
Integrated Services Digital Broadcasting for Terrestrial broadcasting system
3.15
ISO
International Organization for Standardization
3.16
ITU
International Telecommunication Union
3.17
JEITA
Japan Electronics & Information Technology Industries Association
3.18
LO
Local Oscillator
3.19
MER
Modulation Error Ratio
3.20
MPEG
Moving Picture Expert Group
3.21
OFDM
Orthogonal Frequency Division Multiplex
3.22
PRBS
Pseudo Random Binary Sequence
3.23
QAM
Quadrature Amplitude Modulation
3.24
RF
Radiofrequency
3.25
RS
Reed-Solomon
3.26
SFN
Single Frequency Network
62273-1 © IEC:2007(E) – 9 –
4 General conditions of measurement
4.1 Temperature and humidity
Equipment to be measured shall be operated in an environment which meets the temperature
and humidity requirements as defined in their technical specifications. Temperature and
humidity must never be such as to cause condensation on the equipment during
measurements. In the absence of temperature and humidity requirements in the technical
specifications, the provisions of IEC 60244-1 shall apply.
4.2 Conditions for primary power supply
The measurement are carried out at the nominal voltage and the nominal frequency of the
power supply given in relevant equipment specification.
During a series of measurements carried out as part of one test on one equipment, the
voltage and frequency of the power supply shall not deviate from the nominal values more
than indicated in the relevant equipment specification.
When the nominal voltage and frequency cannot be obtained during the measurement, the
following shall apply.
a) If the quantities to be measured depend on voltage and/or frequency and the law
dependence is known, the values are measured at a voltage and frequency which shall
be within the limits laid down in the relevant equipment specification. If necessary, the
measured quantities shall be corrected to the nominal voltage and/or frequency by
calculation.
b) If the quantities to be measured depend on voltage and/or frequency and the law of
dependence is unknown, the values are measured at a voltage and frequency which shall
be within 2 % of nominal voltage and 1 % of the nominal frequency, unless closer
tolerances are specified in the equipment specification.
The conditions for primary power voltage and frequency shall be specified in the
equipment specification. If the conditions for primary power are not specified, the
provisions of IEC 60244-1, Clause 5, shall apply.
Measurements shall be carried out at the nominal voltage and the nominal frequency of
the power supply given in the relevant equipment specification.
4.3 Output power
The tests shall be carried out with the transmitter set to its nominal power output after the
time for stabilization, as defined in the transmitter technical specification, has elapsed.
Nominal output power is taken to mean the average output power as defined by the
manufacturer.
4.4 Test load
The impedance of the test load to which the transmitter is connected shall satisfy the
following requirements.
The nominal value of the test load shall be the same as the line characteristic impedance for
which the transmitter has been designed. The tolerances for this equality shall be the same as
the load tolerances as defined in the transmitter technical specification. The test load
impedance shall remain adequately constant throughout the required frequency band for test
4.5 Auxiliary equipment
If the transmitter technical specification makes reference to related auxiliary units such as
pass-band filters to limit the transmitted signal frequencies or multiplexing units for multiplex
transmissions, these units shall be used during the test.
– 10 – 62273-1 © IEC:2007(E)
4.6 Test equipment and test signals
These test procedures for digital television transmitters require that the test signals used shall
conform to the digital standard implemented in the transmitter (ATSC, DVB-T, ISDB-T) and
that the measuring equipment is sufficiently accurate and stable and has the necessary
dynamic range to provide error-free measurements of transmitter performance parameters.
However, in order to validate the physical layer of the vector r.f. signal that carrying
modulating the input signal. In the case of an ASI type signal, an eye-height measurement
should be taken at the signal input to the transmitter being tested. The eye-height diagram
shows the I and Q time-domain base band modulating signals. Interference caused by
distortions which reduce the eye height can be observed. Limits for the eye-height diagram
are given in Annex A.
5 General characteristics
5.1 Frequency
5.1.1 General
In order to achieve effective use of the radiofrequency spectrum and limit mutual interference
caused by radio services occupying adjacent channels, any departure from the frequency
assignees to a transmitter shall be kept within strictly observed limits. These are defined by
the International Telecommunication Union and are laid down in the Radio Regulations. The
frequency tolerance of frequency bands are given in IEC 60244-1, Annex C. In addition to the
above, for the SFN mode, each transmitter frequency shall be kept within reasonable limits to
avoid the degradation caused by the frequency deviation of plural transmitters. The
acceptable limits for SFN operation depends on the network configuration and transmission
parameters; therefore, the acceptable limits for SFN may be specified for each system.
5.1.2 Characteristic frequency
A frequency which can easily be identified and measured in the occupied band of an emission
The term “characteristic frequency” is used in this standard to denote the actual frequency of
that component of the emission, the nominal value of which is the assigned frequency.
Complementary information is given in Annex B.
5.1.3 Frequency tolerance
The frequency tolerance is the permissible departure of the characteristic frequency of an
emission from the assigned frequency. The frequency tolerance is expressed in parts per 10
or in hertz.
5.1.4 Frequency stability
The frequency stability is the extent to which an emission maintains its assigned frequency
within frequency tolerance.
A random departure from the assigned frequency is expressed as frequency error.
5.1.5 Frequency error
The frequency error is the difference between the assigned frequency and the characteristic
frequency, and shall not exceed the specified frequency tolerance.
The maximum frequency error is expressed in hertz and shall be compared with the frequency
tolerance in the ITU Radio Regulations or with the relevant statement in the equipment
specification.
62273-1 © IEC:2007(E) – 11 –
5.1.6 Frequency drift
The frequency drift of an emission is the uncontrolled continuous and irreversible variation of
frequency against a predetermined time scale.
The latter shall be chosen to identify short-term and/or long-term frequency variations,
expressed in hertz against a defined timescale defined in the technical specification for the
equipment.
Complementary information is given in Annex C.
5.1.7 Frequency-setting error
When a transmitter is set to a particular frequency, the characteristics frequency obtained will
generally differ from the assigned frequency. This is the frequency-setting error.
5.1.8 Condition of operation
The transmitter shall be operated under the conditions given in Clause 4. These conditions
shall be clearly stated together with the condition of modulation.
5.1.9 Methods of measurement of the characteristic frequency of an emission
The characteristic frequency may be measured with any suitable measuring device, provided
that the accuracy attained during the measurement is better than approximately 10 % of the
frequency tolerance of the frequency stability given in the relevant equipment specification of
the transmitter.
NOTE To achieve the required accuracy, the spectrum analyser and, if necessary, the frequency counter used
should be synchronized with a frequency reference independent of the transmitter being tested (GPS 10 MHz or
rubidium standard).
Other methods of great precision use a standard reference frequency, the frequency of which
is known with high accuracy. With such a method, the reception of a standard frequency
transmission may be used to advantage.
When the frequency is to be measured as a function of time, measurements shall be made at
intervals that are short enough to reveal the presence of superimposed periodic variations
and long enough to reveal frequency drift. It is recommended that the measurements are
made with a recording instrument.
The accuracy of the measuring method, if known, shall be stated with the results of the
measurements. If not known, an estimate should be given, based on measuring data.
The conditions of operation shall also be given together with the assigned frequency of the
emission which has been used as the characteristics frequency.
5.2 Output power
5.2.1 General note on output power
For a digital signal with the COFDM modulation process the power is distributed evenly
throughout the transmission channel. Hence, when taking power measurements on such a
signal, the total bandwidth occupied by the modulated signal shall be taken into account. The
product of the mean power of the aerial voltage and current signals is defined as the power
output for a particular channel.
The output power is the first parameter to be measured when checking performance
parameters or carrying out conformity checks. In the case of a digital signal, the mean power
value is the most appropriate for the modulation type being used
– 12 – 62273-1 © IEC:2007(E)
5.2.2 Measuring arrangement
Figure 1 shows the measuring set-up to be used.
5.2.3 Test signal
The transmission parameters of the test signal shall be specified for each system. If no such
specification is given, a signal comprising PRBS 2^23-1-8K 64-QAM 7/8 ¼ from the COFDM
encoder and modulator shall be used.
5.2.4 Method of measurement
5.2.4.1 Calorimetric method
The value for the output power is derived either by measuring the heat dissipated in the test
load or from a bolometer reading of the r.f. signal derived from a calibrated directive coupler
on the transmitter output line. The output power is expressed in watts.
Directional
coupler
Digital Auxiliary Terminating
transmitter unit load
Bolometer
IEC 128/07
Figure 1 – Measuring set-up for output power
When the temperature rise of the water in the test load is used to derive the output power
value, the following two sets of readings are taken so as to minimize the thermometer errors.
a) Thermometer A: water temperature at load inlet; Thermometer B: water temperature at
load outlet
b) Thermometer B: water temperature at load inlet; Thermometer A: water temperature at
load outlet
Inlet and outlet temperatures are taken as the averages of the two readings in each case.
The output power value is derived from the following formula:
P(W) = 0,069D.Δθ
where
P(W) is the measured power;
D is the water flow rate in litres per minute;
Δθ: is the difference between the load inlet and the outlet water temperatures in °C.
This formula only applies in the absence of additives to the water.
62273-1 © IEC:2007(E) – 13 –
When a bolometer reading of the r.f. signal from a calibrated directional coupler is used to
derive the output power value, the following formula is used:
ATT/10
P(W) = (10 ) × (Pm) × (cal factor)
where
P(W) is the measured power;
ATT(dB) is the attenuation of the directional coupler;
cal factor(%) is the calibration factor for the bolometer probe at the operating frequency.
The method of calibration of the directional coupler is given in Annex D.
Since the output power value is a fundamental reference point when quantifying non-linear
distortion parameters, it is recommended that a permanent output power reading is displayed
by a measuring instrument capable of measuring the r.f. signal from the directional coupler
which is bridged across the output r.f. line. This reading shall be available throughout the
validation of the transmitter performance parameters.
5.2.4.2 Spectrum analyser method
a) Set the modulator output to reference signal
b) Connect a spectrum analyser to the measurement point, using a cable the loss of
which has been calibrated. If the power level at the measurement point is too high,
adjust it in such a way that it falls within the measurement range of the spectrum
analyser, using a calibrated directional coupler and attenuator.
c) Setting of the spectrum analyser
Centre frequency Span RBW VBW Detect mode Channel BW
Centre frequency of the 10 MHz 30 kHz 300 kHz Sample detection See note
modulated wave
NOTE The channel bandwidth is defined for each system. Use the channel power measurement to measure the
power.
d) Determine the power from the reading of the spectrum analyser and the calibration
value.
Power (dBm) = Spectrum analyser reading (dBm) + cable loss (dB) + calibration value (dB)
+
directional coupler coupling factor (dB) + attenuator value
p(dBm)/10
P(W) = 10 /1000
– 14 – 62273-1 © IEC:2007(E)
5.3 Spurious domain emission
5.3.1 Definition
Spurious emission is an emission on a frequency or frequencies which are outside the
necessary bandwidth and the level of which may be reduced without affecting the
corresponding transmission of information. Spurious emissions include harmonic emissions,
parasitic emissions, intermodulation products, frequency conversion products, and single
sideband phase noise, but exclude out-of-band emissions (Article 1, No. 1.145 of the ITU
Radio Regulations).
The reference bandwidth is the bandwidth in which the spurious emission level is specified.
5.3.2 Method of measurement
Measurements are taken using the set-up shown in Figure 2. The directive coupler which
bridges the output transmission line shall have an appropriate directivity; also, its frequency
response (with a fall-off of 6 dB per octave) shall be taken into account when taking
measurements. A spectrum analyser having a dynamic range of at least 70 dB and with a
resolution bandwidth between 1 kHz and 1 MHz shall be used. The dynamic range of the
measurement should be extended by the use of appropriate filters. The transmission
parameter of the test signal shall be specified for each system. If no such specification is
given, a signal comprising PRBS 2^23-1 8K 64-QAM 7/8 ¼ from the COFDM encoder and
modulator is used.
The limits are absolute value or attenuation compared to the average output power supplied
by the transmitter; at nominal power the harmonic level shall be measured at the same
resolution bandwidth.
The values shall be expressed in W/dBm or dB.
Complementary information is given in Annex E.
5.4 Out-of-band domain emission
5.4.1 Definition
Out-of-band emission is an emission on a frequency or frequencies immediately outside the
necessary bandwidth which results from the modulation process, but excluding spurious
emissions (Article 1, No. 1.144 of the ITU Radio Regulations). The boundary between the out-
of- band and spurious domain occurs at a separation of ±250 % of necessary bandwidth.
The value of the out-of-band emission shall be defined for critical and non-critical mask.
5.4.2 Method of measurement
Measurements are taken using the set-up shown in Figure 2. The transmission parameter set
of test signal shall be specified for each system, but, unless specified, PRBS 2^23-1 8K
64-QAM 7/8 ¼ from the COFDM encoder and modulator is used.
Power values of out-of-band signals are measured with an r.f. spectrum analyser whose
resolution is specified for each system, but, unless specified, the parameter sets shown in
Table 1 shall apply. The frequencies at which power values are measured are chosen in
relation to the central channel frequency. The results are given in a table or as a graph in
which relative values in dB are given for frequencies that are related to the centre channel
frequency
62273-1 © IEC:2007(E) – 15 –
Table 1 – Measurement parameters for out-of-band emission
Centre frequency Sweep range Resolution Filter Detect mode Note
(span) bandwidth passband
(RBW) (VBW)
Centre frequency of the 500 % of the 4 kHz 4 kHz Positive peak Standard for
r.f. signal necessary detection DVB-T system
bandwidth
Centre frequency of the 500 % of the 10 kHz 300 Hz or Positive peak Standard for
r.f. signal necessary lower detection ISDB-T system
bandwidth
Power output
reading
Directional
coupler
Digital
Auxiliary Terminating
transmitter unit load
Spectrum
analyser
IEC 129/07
Figure 2 – Measuring set-up for spurious emission,
out-of-band emission and bandwidth
5.5 Occupied bandwidth
5.5.1 Definition
The width of a frequency band is such that, below the lower and above the upper, frequency
limits the mean powers emitted are each equal to a specified percentage β/2 of the total mean
power of a given emission.
Unless otherwise specified in an ITU-R Recommendation for the appropriate class of emission
the value of β/2 should be taken as 0,5 % (Article 1, No. 153 of the ITU Radio Regulations)
5.5.2 Method of measurement
Measurements are taken using the set-up shown in Figure 2. The transmission parameter set
of test signal shall be specified for each system, but, unless specified, PRBS 2^23-1 8K
64-QAM 7/8 ¼ from the COFDM encoder and modulator is used.
Power values of signals are measured with an r.f. spectrum analyser whose resolution is
specified for each system, but unless specified, the parameter sets are shown in Table 2.
The bandwidth should be determined containing 99 % of the energy of COFDM signal from
the spectrum measured by the spectrum analyser.
– 16 – 62273-1 © IEC:2007(E)
Table 2 – Measurement parameters for occupied bandwidth
Centre frequency Sweep range Resolution Filter Detect mode Note
(span) bandwidth passband
(RBW) (VBW)
Centre frequency of 20 MHz 4 kHz 4 kHz Positive peak Standard for
the r.f. signal detection DVB-T system
Centre frequency of 20 MHz 10 kHz 300 Hz or Positive peak Standard for
the r.f. signal lower detection ISDB-T system
Complementary information is given in Annex E.
5.6 Power consumption
This parameter is measured in conformity with 5.4 of IEC 60244-1. The transmission
parameter set of test signals shall be specified for each system, but, unless specified, PRBS
2^23-1 8K 64-QAM 7/8 ¼ from the COFDM encoder and modulator is used.
6 Transmitted signal characteristics
6.1 Intermodulation (shoulders)
6.1.1 Definition
For the multi-carrier transmission system such as COFDM, intermodulation distortion mainly
caused by transmitter non-linearity may affect the critical degradation to the COFDM signal.
Intermodulation distortion is composed of unwanted spectral energy both in-band and out-of-
band. The in-band energy will cause the degradation of the transmitted signal and the out-of-
band energy will cause adjacent channel interference.
The quantity of intermodulation distortion products may be measured as the out-of-band
emission of the transmitter. This out-of band emission is named “shoulder attenuation”.
NOTE Out-of-band emission caused by the transmitter may be decreased by an output filter. Therefore, shoulder
attenuation should be measured without an output filter.
6.1.2 Methods of measurement
Measurements are taken using the set-up shown in Figure 2. The transmission parameter set
of test signals shall be specified for each system, but, unless specified, PRBS 2^23-1 8K 64-
QAM 7/8 ¼ from the COFDM encoder and modulator is used.
Power values of out-of-band signals are measured with an r.f. spectrum analyser whose
resolution is specified for each system, but, unless specified, the parameter sets shown in
Table 1 shall apply. The frequencies at which power values are measured are chosen in
relation to the centre channel frequency. The difference of maximum value of the in-band
spectrum and the measured value of the out-of-band spectrum is defined as a ”shoulder
attenuation”. The frequencies of out-of-band emission for measurement shall be specified for
each system.
Complementary information is given in Annex F.
62273-1 © IEC:2007(E) – 17 –
6.2 Modulation error ration (MER)
6.2.1 Definition
This parameter is a measure of the total degradation in the transmitted signal due to residual
carrier presence (i.e., carrier not totally suppressed) and amplitude/frequency and
phase/frequency response degradations. It should be determined with the use of a receiver
with the lowest possible noise factor in order to avoid causing distortion. The MER value is
derived from the following formula.
N
⎧ ⎫
where
2 2
⎪ ()I +Q ⎪
I is the in-phase component; ∑ j j
⎪ ⎪
⎪ ⎪
j=1
Q is the quadrature
MER = 10 lg dB
⎨ ⎬
N
component;
⎪ ⎪
2 2
()δI + δQ
j j
N is the number of carriers; ∑
⎪ ⎪
⎪ ⎪
j=1
J is the carrier index. ⎩ ⎭
The sum of the square of the magnitudes of the ideal symbol vectors is divided by the sum of
the square of the magnitudes of the symbol error vectors. The result expressed as a power
ratio in dB, is defined as the modulation error ratio.
6.2.2 Method of measurement
Measurements are taken at the transmitter output using the set-up shown in Figure 2; an MER
measuring unit is used instead of the spectrum analyser. The modulation parameters shall be
specified for each system. If no such specification is given, measurements shall be carried out
using QPSK, 16-QAM and 64-QAM signals.
Measurements shall be taken on all carriers, with an integration period to enable a sufficient
number of samples to be averaged. Unless otherwise specified, 100 OFDM samples shall be
averaged. The performance to be achieved will be specified in the technical specification for
the equipment.
Complementary information is given in Annex G
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