IEC 62634:2015

IEC 62634 ®
Edition 2.0 2015-03
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Radio data system (RDS) – Receiver products and characteristics – Methods of
measurement
Système de radiodiffusion de données (RDS) – Récepteurs et caractéristiques –
Méthodes de mesure
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IEC 62634 ®
Edition 2.0 2015-03
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Radio data system (RDS) – Receiver products and characteristics – Methods of

measurement
Système de radiodiffusion de données (RDS) – Récepteurs et caractéristiques –

Méthodes de mesure
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 33.060.20 ISBN 978-2-8322-2267-6

– 2 – IEC 62634:2015 © IEC 2015
CONTENTS
FOREWORD . 4
INTRODUCTION . 6
1 Scope . 7
2 Normative references. 7
3 Terms, definitions and abbreviations . 7
3.1 Terms and definitions . 7
3.2 Abbreviations . 8
4 Measuring method . 8
4.1 Standard measuring signal . 8
4.2 RDS data conditions . 9
4.2.1 General . 9
4.2.2 Matching circuit . 9
5 Measurement of the RDS sensitivity . 10
5.1 General . 10
5.2 Method of measurement . 10
5.3 Presentation of the results . 10
6 Measurement of the RDS data acquisition . 10
6.1 General . 10
6.2 Time to synchronise . 10
6.3 Time to detect a first PI . 11
6.4 Method of measurement . 11
7 Measurement of the large signal capabilities . 11
7.1 General . 11
7.2 Resistance to high wanted signal levels . 11
7.2.1 Method of measurement . 11
7.2.2 Large wanted signal requirement . 11
7.3 RDS performance at large unwanted signal . 11
7.3.1 Method of measurement . 11
7.3.2 Large unwanted signal requirements . 12
8 Measurement of the RDS selectivity . 12
8.1 General . 12
8.2 Method of measurement . 12
9 Considerations and guidelines for evaluation of the dynamic RDS performance . 13
9.1 General . 13
9.2 RDS dynamic behaviour . 13
9.3 Traffic announcements TA/TP . 14
9.3.1 TA message . 14
9.3.2 End of TA message . 14
9.3.3 TP search . 14
9.3.4 TA announcement skip . 14
9.4 Regionalisation . 14
9.4.1 Implementations . 14
9.4.2 Requirement . 15
Bibliography . 16

Figure 1 – Coupling circuit . 9
Figure 2 – Matching circuits for RDS product devices with three different input
impedances . 9

Table 1 – Presentation of the measurement result . 12
Table 2 – AF example . 15

– 4 – IEC 62634:2015 © IEC 2015
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
RADIO DATA SYSTEM (RDS) – RECEIVER PRODUCTS
AND CHARACTERISTICS – METHODS OF MEASUREMENT

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,
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Publication(s)”). Their preparation is entrusted to technical committees; any IEC National Committee interested
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with the International Organization for Standardization (ISO) in accordance with conditions determined by
agreement between the two organizations.
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5) IEC itself does not provide any attestation of conformity. Independent certification bodies provide conformity
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services carried out by independent certification bodies.
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
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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 62634 has been prepared by technical area 1: Terminals for audio,
video and data services and contents, of IEC technical committee 100: Audio, video and
multimedia systems and equipment.
This second edition cancels and replaces the first edition published in 2011. This edition
constitutes a technical revision.
This edition includes the following significant technical changes with respect to the previous
edition:
• the ±100 kHz test measurement case from Clause 8 of IEC 62634:2011 was deleted as it
did not permit to achieve stable and reproducible measurement results;
• an error has been corrected. The term “de-emphasis” shall read correctly “pre-emphasis”.

The text of this standard is based on the following documents:
CDV Report on voting
100/2121/CCDV 100/2419/RVC
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 committee has decided that the contents of this publication will remain unchanged until
the stability date indicated on the IEC website 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.
– 6 – IEC 62634:2015 © IEC 2015
INTRODUCTION
This International Standard gives commonly agreed measuring methods to complement the
RDS standard IEC 62106 and the RBDS standard (NRSC-4-A) in the USA.
The RDS measuring methods presented here are directed at all manufacturers of RDS
receiver products, and in particular tuner modules with embedded RDS functionality, including
TMC (see ISO 14819 series of standards).

RADIO DATA SYSTEM (RDS) – RECEIVER PRODUCTS
AND CHARACTERISTICS – METHODS OF MEASUREMENT

1 Scope
This International Standard describes how to measure minimum RDS receiver performance
requirements which concern three RDS receiver product categories. However, it should be
noted that there are also RDS receiver products on the market that significantly out-perform
the minimum RDS receiver performance requirements quoted.
Methods and algorithms to achieve automatic programme service-following by means of AF
lists are, however, very customer- and manufacturer-specific, and are therefore not covered in
this standard.
2 Normative references
The following documents, in whole or in part, are normatively referenced in this document and
are indispensable for its application. For dated references, only the edition cited applies. For
undated references, the latest edition of the referenced document (including any
amendments) applies.
IEC 62106, Specification of the Radio Data System (RDS) for VHF/FM sound broadcasting in
the frequency range from 87,5 MHz to 108,0 MHz
3 Terms, definitions and abbreviations
3.1 Terms and definitions
For the purposes of this document, the following terms and definitions apply. Terms and
definitions of the RDS features used shall be found in IEC 62106.
3.1.1
RDS product category 1
RDS receiver product with high-ohmic input impedance
EXAMPLE For portable devices.
3.1.2
RDS product category 2
RDS receiver product with 50 Ω input impedance
EXAMPLE Car radio optimized for active antenna.
3.1.3
RDS product category 3
RDS receiver product with 75 Ω input impedance
EXAMPLE Car radio optimized for rod antenna or home receiver.
3.1.4
RDS reception
the signal at which the RDS signal is received with 50 % non-corrected error-free blocks
Note 1 to entry: In practice, the level at which the TP bit is immediately detected.

– 8 – IEC 62634:2015 © IEC 2015
3.1.5
large signal behaviour
capability of the RDS receiver to fulfil its function at or in the neighbourhood of strong FM
signals
3.1.6
RDS selectivity
capability of the RDS receiver to cope with adjacent signals at both sides of the tuning
frequency: ± 200 kHz
3.2 Abbreviations
For the purposes of this document, the following abbreviations apply.
AF Alternative Frequency
dBµV Signal level in µV; 0 dBµV = 1 µV, 6 dBµV = 2 µV, 20 dBµV = 10 µV
EON Enhanced Other Networks information
FM Frequency Modulation
GUI Graphic User Interface
IPR Intellectual Property Rights
PI Programme Identification
PND Personal Navigation Device
PS Programme Service name
PTY Programme TYpe
RDS Radio Data System
RBDS USA Radio Data System
S+200 Unwanted signal, +200 kHz offset from the wanted signal
S−200 Unwanted signal, −200 kHz offset from the wanted signal
TA/TP Traffic Announcement/Traffic Programme
TMC Traffic Message Channel
4 Measuring method
4.1 Standard measuring signal
Unless otherwise stated, the following measuring signal shall be applied.
Tuning frequency 97,1 MHz
Signal input level V 60 dBµV
i
Deviation ∆f 22,5 kHz
Modulation frequency F 1 kHz
mod
Pilot 19 kHz deviation 6,75 kHz
Modulation method L = R
Deviation RDS carrier ∆f 2 kHz
RDS
Pre-emphasis 50 µs  (USA: 75 µs)
Where an unwanted signal will be added, for RDS car radio selectivity measurements, this will
be done with the coupling circuit shown in Figure 1. The circuit shows how to couple two

See NRSC-4-A, RBDS standard cited in the Bibliography.

generators with 50 Ω output so that the total output impedance remains 50 Ω. Depending on
the input impedance, one of the matching circuits shown in Figure 2 should be applied in
addition.
50 Ω 16,7 Ω
16,7 Ω
Car radio
G
V1
EMF
50 Ω 16,7 Ω
50 Ω
G
V2
EMF
IEC
Figure 1 – Coupling circuit
4.2 RDS data conditions
4.2.1 General
The RDS data shall consist of an appropriate PI code, a PS name, one or more AFs and
chosen values for, e.g. TP (=1), DI (=0000), TA (=0), PTY (=00001) and M/S (=1), with a
maximum repetition rate for group type 0A of four groups per second. Use group type A only.
4.2.2 Matching circuit
For the three types of RDS product devices (modules for portable devices, car radio and
home receiver), the matching circuit is given in Figure 2.
RDS RDS
50 Ω product 50 Ω product
R R
i i
G G
50 Ω
x kΩ
V V V V
EMF i EMF i
RDS device with RDS device with

high input impedance 50 Ω input impedance

RDS
product
50 Ω 10 Ω 45 Ω
R
i
G
60 Ω
75 Ω
V V
EMF i
RDS device with
75 Ω input impedance
IEC
Figure 2 – Matching circuits for RDS product devices
with three different input impedances

– 10 – IEC 62634:2015 © IEC 2015
RF generators have a characteristic impedance of 50 Ω. For a device with an input impedance
of 50 Ω, no additional matching circuit is needed. The antenna input signal V is then
i
V − 6 dB. In case of a category 1 device like a PND, which generally has a high input
EMF
impedance, V is then almost equal to the generator voltage V . When the input impedance
i EMF
cannot be ignored in relation to the 50 Ω generator impedance, the correction shall be
calculated separately.
EXAMPLE For a device with 2 kΩ input impedance this will give V = V × 2 000/(2 000 + 50) and in dBµV this
i EMF
yields V dBµV = V dBµV − 0,2 dBµV.

i EMF
5 Measurement of the RDS sensitivity
5.1 General
The lowest FM input signal is determined for which RDS reception is obtained.
5.2 Method of measurement
The receiver and the signal source are operated under standard measuring conditions,
according to 4.1.
a) When a GUI is available, which is capable of measuring good and bad blocks, then a
reading of 50 % good blocks is an accurate result for the sensitivity measurement. The
ratio should be calculated over at least 2 000 receivable blocks.
b) A good alternative in the case, where a GUI and statistical read-out is not available to
measure the level of correctly received RDS blocks, is the TP flag.
Turn the signal level up until 50 % error free RDS blocks are received. Alternatively, turn the
signal level up until the TP flag lights up. Repeat this three times and take the average value
of these three observations.
If the TP flag cannot be displayed, then the complete PS can be used instead. However, care
should be taken that a new programme service name is entered into the RDS encoder each
time a new measurement is done. The new programme service name shall differ from the
previous one in all eight characters.
5.3 Presentation of the results
The result is presented in dBµV.
Minimum receiver sensitivity requirement: RDS product category 1 21 dBµV
RDS product category 2 18 dBµV
RDS product category 3 18 dBµV
6 Measurement of the RDS data acquisition
6.1 General
Particularly for tuner modules or circuits with RDS fully integrated for mobile use, it is
important to know the time to synchronize after a re-tune. Strongly related to this is the time
to receive the PI code for the first time.
6.2 Time to synchronise
When tuned to an FM-RDS station, it is important to have RDS synchronisation immediately.

Taking into account the synchronising time of the system and the recognition of at least two
consecutive RDS blocks, the time to synchronise RDS shall be maximum 120 ms, 80 % over
100 measurements.
6.3 Time to detect a first PI
In addition to the time to synchronise, it is often required to specify the time to detect the PI
code for the first time. There is a fixed relationship between both, the PI code is present in
block A of all groups and in block C’ of the B groups. The maximum time shall not exceed
180 ms. A value of 160 ms shall not be exceeded in 80 % over 100 measurements.
6.4 Method of measurement
The tuner module or receiver and the signal source are operated under standard measuring
conditions, according to 4.1.
The RDS monitor program on the PC screen shall provide the information of time needed to
synchronise. Tune from a frequency higher and a frequency lower than the wanted frequency
of 97,1 MHz. (Tuning should be from both sides of the wanted frequency, because the
behaviour can be different). Read out the value for the time needed to synchronise and the
time needed to read the PI code.
Repeat this at least 100 times. 80 % of the results shall then be below the minimum
requirements.
The following minimum requirements apply.
Time to synchronise 120 ms
Time to PI detection 160 ms
7 Measurement of the large signal capabilities
7.1 General
The two issues to be dealt with are the following.
a) The product shall be resistant to high signal levels of the wanted frequency.
b) RDS decoding shall work correctly in the presence of strong FM signals other than the
wanted one.
7.2 Resistance to high wanted signal levels
7.2.1 Method of measurement
The tuner module or receiver and the signal source are operated under standard measuring
conditions, according to 4.1; turn the input signal level up until 120 dBµV.
7.2.2 Large wanted signal requirement
No defects shall occur.
7.3 RDS performance at large unwanted signal
7.3.1 Method of measurement
The tuner module or receiver and the signal source are operated under standard measuring
conditions according to 4.1. In addition, one of the signals according to Table 1 is added.

– 12 – IEC 62634:2015 © IEC 2015
Table 1 – Presentation of the measurement result
Wanted frequency Unwanted frequency Result
97,1 MHz 91,1 MHz ____ dBµV
RDS sensitivity level +6 dB 103,1 MHz
____ dBµV
The wanted and unwanted signals are applied simultaneously by means of a combining
network in accordance with 4.1. Adjust the RF level of the wanted frequency to the RDS
sensitivity level (50 % correct RDS blocks) without the unwanted signal. Add 6 dB to this level.
Adjust the unwanted strong signal until the RDS sensitivity level of 50 % correct blocks is
reached again.
7.3.2 Large unwanted signal requirements
The following are minimum large unwanted signal requirements:
RDS product category 1 RDS reception at 50 % correct blocks 60 dBµV
RDS product category 2 and 3 RDS reception at 50 % correct blocks 88 dBµV
8 Measurement of the RDS selectivity
8.1 General
RDS selectivity: The capability of the RDS receiver to cope with adjacent signals at both sides
of the tuning frequency: ± 200 kHz.
8.2 Method of measurement
The wanted and unwanted signals are applied simultaneously by means of a combining
network in accordance with Figure 1. Adjust the RF level of the wanted frequency without the
unwanted signal to the RDS sensitivity level (50 % correct RDS blocks).
Add 6 dB to this level.
Add the unwanted frequency: Tuned wanted frequency with a distance of ± 200 kHz
Deviation ∆f 22,5 kHz
Modulation frequency F 1 kHz
mod
Modulation method L = R
Pre-emphasis 50 µs (USA: 75 µs)
Check the RDS reception. Adjust the unwanted signal until the RDS sensitivity level of 50 %
error-free blocks is reached again.
The level of the unwanted signal related to the wanted signal in dB is presented as
S+200, S-200 RDS selectivity.
The following are minimum RDS selectivity requirements:
• RDS product category 1: S ± 200  32 dB
• RDS product category 2: S ± 200  50 dB
• RDS product category 3: S ± 200  50 dB

9 Considerations and guidelines for evaluation of the dynamic RDS
performance
9.1 General
The issues in this clause are highly significant for a well performing RDS product, mostly car
radios. However, clear performance values and levels cannot be given, because of
manufacturer and/or customer specific implementations. Therefore a set of general
considerations and guidelines is given here with the view to help to evaluate the dynamic RDS
performance in the products concerned.
9.2 RDS dynamic behaviour
An ideal RDS radio switches in time inaudibly over to an alternative frequency (AF) with the
best audio quality. Variations in sound should not occur.
Car radio manufacturers have developed algorithms to achieve this in the best possible way.
Therefore objective criteria or switching levels will not be specified, as they are often subject
to IPR. In this standard a few key criteria are nevertheless given, which will need to be taken
into account, where applicable, in order to ensure a proper dynamic behaviour of the RDS
product.
a) Signal level of an AF in relation to the tuned frequency.
b) Multipath distortion: Distortion of the audio, caused by reflections, like in mountainous
areas.
c) Noise: Unwanted signals in higher parts of the audio spectrum, generally coming from
adjacent FM channels.
d) RDS reception: The number of correctly received RDS blocks; valid for the tuned
frequency only. This is also relevant for TMC reception.
A radio will receive either single (Method A) or multiple (Method B) AF list(s). The order, in
which these AFs are stored and used, is manufacturer specific. Important is, however, that the
radio checks these AFs at certain intervals, to identify their quality, taking those first three
criteria mentioned above into account. All modern tuners nowadays offer the possibility of
doing these AF checks in an almost “inaudible” way. When the overall signal quality of an AF
from the list becomes better than the currently tuned frequency, then the radio shall switch to
this better AF.
Correct processing of the PI code: Before releasing the audio of the new frequency however,
first a PI check shall be made in order to verify that the new frequency carries indeed the
same wanted radio programme.
Manufacturers of car radios have developed and optimized over the years algorithms to adapt
the dynamic RDS performance to most challenging receiving conditions. We have to consider
here mountainous areas, tunnel roads and areas with a poor coverage. Quite often the AF
lists are exceeding 25 AF or sometimes even 30 AFs.
RDS car radios that are capable to cope with these complex receiving conditions, can well
make the difference in comparison to more average or poor and not so well performing radios.
The car industry has been deeply involved in evaluating this process.
Simulations on the bench may give only a first impression and show, if the most basic
functions will work properly. However, the real dynamic RDS performance at these
challenging conditions can only be validated at critical locations and on the roads, where such
critical receiving conditions then really occur.
A simple bench test can start with only two or three generators with programmable AF lists, to
make sure that the radio will at least “recognise” each generator, when tuned to just one of

– 14 – IEC 62634:2015 © IEC 2015
them. By varying the signal level or introducing multipath or noise distortion to the tuned
frequency (= generator), the radio shall look for the best alternative frequency (= one of the
other generators) and then switch accordingly.
9.3 Traffic announcements TA/TP
9.3.1 TA message
The following customer requirements apply.
The radio shall detect a Traffic announcement (TA) on the tuned programme (TP) or one of
the cross-linked programmes via EON. The radio shall switch to the TA message from any
source currently in use.
During a TA, the display indication and the volume level are either product specific or
customer adjustable.
9.3.2 End of TA message
After the TA message, the radio shall return to the previous status.
When, during the traffic message, RDS synchronization is lost, the radio shall return to the
previous situation within a fixed period. A practical value is 2 min.
9.3.3 TP search
When a TP or TP/EON search is started, it will be done according to the following criteria.
The radio stops at the first station, which corresponds to TP = 1 being present in all groups or
TP/EON being signalled in the type 0A group.
According to the following status of the TP and TA flags in the 0A group, i.e. TP = 1 and
TA = 0, or TP = 0 and TA = 1 or TP = 1 and TA = 1, a traffic announcement is currently on air,
or not.
NOTE A TP search action can typically be initiated in 3 different ways:
a) the user switches on the TP or TP/EON function and the radio is currently not tuned to a TP or TP/EON station;
b) the user starts a search action while the TP or TP/EON function is active;
c) the radio is tuned to a TP or TP/EON station and the RF signal level drops below the RDS synchronization
level AND the current audio source is not the radio, but, for instance, a CD or MP3 or….
If in case c) the audio source is radio, the search action may not be automatically initiated by the radio itself as
the audio quality may well be at an acceptable level when RDS synchronization is lost. When this situation
occurs it might be very confusing to the customer if the radio would start a search action while the audio
quality is still at an acceptable level.
9.3.4 TA announcement skip
A current TA message can be interrupted at customer request. The next TA message will,
however, be passed on, when the TA receiving mode remains on.
9.4 Regionalisation
9.4.1 Implementations
Regional services use PI codes that are identical in the first, third and fourth-nibbles, but have
different second-nibbles in the range 4 to F (Region 1 to 12). Broadcasters may split during
certain periods of the day their supra-regional network into a maximum of 12 regional
networks. In Austria, Germany and Switzerland this regionalisation feature is very widely used.
The PI code structure will be x3yz, and when regionalized, the second PI segment may

change then from 3 into 4 to F. Often the PS name also changes dynamically, to communicate
the regional status to the listener, i.e. BAYERN1 becomes BR1 MUN, when regional.
Another public broadcaster in Germany uses the concept of regionalisation completely static,
i.e. the area codes in the second PI segment are kept as one value from the code range 4 to
F and the PS name also remains unchanged and refers to the region. In this configuration
there can be a supra-regional common radio programme for certain hours of the day, without
using the supra-regional code 3 at all in the second PI segment.
AF method B lists give all AFs in frequency pairs, with the parent frequency in ascending or
descending order, indicating then also the regional variants for that radio tuned programme.
The tuning frequency is given in the header of the list. Table 2 illustrates this issue.
Table 2 – AF example
F F
1 2
# 11 89,3 Total number (11) of frequencies for tuning frequency (89,3)
89,3 99,5 F > F hence 99,5 is an AF of tuned 89,3 and is the same programme
2 1
89,3 101,7 F > F hence 101,7 is an AF of tuned 89,3 and is the same programme
2 1
88,7 89,3 F > F hence 88,7 is an AF of tuned 89,3 and is the same programme
2 1
102,5 89,3 F < F hence 102,5 is an AF of the regional programme variant for tuned 89,3
2 1
89,5 89,1 F < F hence 89,1 is an AF of the regional programme variant for tuned 89,5
2 1
9.4.2 Requirement
Although various product and customer specific implementations may exist, RDS radios shall
manage and store PI codes and dynamically change their structure into regional programme
variants in a proper way.
The AF list shall be structured in such a way that a distinction is given between the AFs
belonging really to the same supra-regional PI and the ones belonging to the associated
programmes, whose PI differs then only in the second PI segment.

– 16 – IEC 62634:2015 © IEC 2015
Bibliography
ISO 14819 (all parts), Intelligent transport systems – Traffic and travel information messages
via traffic message coding
NRSC-4-A, National Radio Systems Committee: United States RBDS standard – Specification
of the radio broadcast data system (RBDS)
Kopitz, D. and Marks,B., RDS – The Radio Data System, published by Artech House
Publishers, Boston and London, 1999, ISBN 0-89006-744-9

____________
– 18 – IEC 62634:2015 © IEC 2015
SOMMAIRE
AVANT-PROPOS . 20
INTRODUCTION . 22
1 Domaine d'application . 23
2 Références normatives . 23
3 Termes, définitions et abréviations . 23
3.1 Termes et définitions . 23
3.2 Abréviations . 24
4 Méthode de mesure . 24
4.1 Signal normalisé pour les mesures . 24
4.2 Conditions pour les données RDS . 25
4.2.1 Généralités . 25
4.2.2 Circuit d’adaptation . 25
5 Mesure de la sensibilité RDS . 26
5.1 Généralités . 26
5.2 Méthode de mesure. 26
5.3 Présentation des résultats . 26
6 Mesure de l'acquisition de données RDS . 26
6.1 Généralités . 26
6.2 Temps de synchronisation . 27
6.3 Temps nécessaire à la détection d’un premier code PI . 27
6.4 Méthode de mesure. 27
7 Mesure des capacités en signal fort . 27
7.1 Généralités . 27
7.2 Résistance aux niveaux forts du signal utile . 27
7.2.1 Méthode de mesure . 27
7.2.2 Exigence pour un signal utile fort . 27
7.3 Performance RDS à un signal perturbateur de niveau fort . 28
7.3.1 Méthode de mesure . 28
7.3.2 Exigences vis à vis d'un signal perturbateur fort . 28
8 Mesure de la sélectivité RDS . 28
8.1 Généralités . 28
8.2 Méthode de mesure. 28
9 Considérations et lignes directrices concernant l’évaluation de la performance
dynamique RDS . 29
9.1 Généralités . 29
9.2 Comportement dynamique RDS . 29
9.3 Flashs d’informations routières TA/TP . 30
9.3.1 Message d’informations routières . 30
9.3.2 Fin de message TA . 30
9.3.3 Recherche de TP . 30
9.3.4 Saut d’un flash TA . 31
9.4 Régionalisation . 31
9.4.1 Mises en œuvre . 31
9.4.2 Exigence . 31

Bibliographie . 32

Figure 1 – Circuit de couplage. 25
Figure 2 – Circuits d’adaptation pour les produits RDS avec trois impédances d’entrée
différentes . 25

Tableau 1 – Présentation du résultat de mesure . 28
Tableau 2 – Exemple d’AF .
...