ISO 11452-11:2010

INTERNATIONAL ISO
STANDARD 11452-11
First edition
2010-09-01
Road vehicles — Component test
methods for electrical disturbances from
narrowband radiated electromagnetic
energy —
Part 11:
Reverberation chamber
Véhicules routiers — Méthodes d'essai d'un équipement soumis à des
perturbations électriques par rayonnement d'énergie électromagnétique
en bande étroite —
Partie 11: Chambre réverbérante

Reference number
©
ISO 2010
PDF disclaimer
This PDF file may contain embedded typefaces. In accordance with Adobe's licensing policy, this file may be printed or viewed but
shall not be edited unless the typefaces which are embedded are licensed to and installed on the computer performing the editing. In
downloading this file, parties accept therein the responsibility of not infringing Adobe's licensing policy. The ISO Central Secretariat
accepts no liability in this area.
Adobe is a trademark of Adobe Systems Incorporated.
Details of the software products used to create this PDF file can be found in the General Info relative to the file; the PDF-creation
parameters were optimized for printing. Every care has been taken to ensure that the file is suitable for use by ISO member bodies. In
the unlikely event that a problem relating to it is found, please inform the Central Secretariat at the address given below.

©  ISO 2010
All rights reserved. Unless otherwise specified, 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 either ISO at the address below or
ISO's member body in the country of the requester.
ISO copyright office
Case postale 56 • CH-1211 Geneva 20
Tel. + 41 22 749 01 11
Fax + 41 22 749 09 47
E-mail copyright@iso.org
Web www.iso.org
Published in Switzerland
ii © ISO 2010 – All rights reserved

Contents Page
Foreword .iv
Introduction.v
1 Scope.1
2 Normative references.1
3 Terms and definitions .1
4 Test conditions .3
5 Test location .3
5.1 General .3
5.2 Reverberation chamber .3
6 Test apparatus and instrumentation .3
6.1 Isotropic E-field probe .3
6.2 RF signal generator.3
6.3 Transmitting and receiving antennas.4
6.4 Power amplifiers.4
6.5 Spectrum analyser .4
6.6 Directional coupler .4
6.7 Power meter .4
6.8 Computer control .4
6.9 Stimulation and monitoring of the DUT .4
7 Test set-up .5
7.1 General .5
7.2 Ground plane and DUT grounding .5
7.3 Power supply and AN.5
7.4 Location of DUT and wiring harness.6
7.5 Location of load simulator.6
7.6 Location of transmitting antenna .6
7.7 Location of receiving antenna .6
8 Test method .8
8.1 Test plan.8
8.2 Test procedure.8
8.3 Test report.9
Annex A (informative) Function performance status classifications (FPSC) .11
Annex B (normative) Mode tuning chamber characterization .12
Annex C (normative) Determination of chamber loading effects .18
Annex D (normative) Artificial network .21
Bibliography.23

Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards bodies
(ISO member bodies). The work of preparing International Standards is normally carried out through ISO
technical committees. Each member body interested in a subject for which a technical committee has been
established has the right to be represented on that committee. International organizations, governmental and
non-governmental, in liaison with ISO, also take part in the work. ISO collaborates closely with the
International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization.
International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 2.
The main task of technical committees is to prepare International Standards. Draft International Standards
adopted by the technical committees are circulated to the member bodies for voting. Publication as an
International Standard requires approval by at least 75 % of the member bodies casting a vote.
Attention is drawn to the possibility that some of the elements of this document may be the subject of patent
rights. ISO shall not be held responsible for identifying any or all such patent rights.
ISO 11452-11 was prepared by Technical Committee ISO/TC 22, Road vehicles, Subcommittee SC 3,
Electrical and electronic equipment.
ISO 11452 consists of the following parts, under the general title Road vehicles — Component test methods
for electrical disturbances from narrowband radiated electromagnetic energy:
⎯ Part 1: General principles and terminology
⎯ Part 2: Absorber-lined shielded enclosure
⎯ Part 3: Transverse electromagnetic mode (TEM) cell
⎯ Part 4: Harness excitation methods
⎯ Part 5: Stripline
⎯ Part 7: Direct radio frequency (RF) power injection
⎯ Part 8: Immunity to magnetic fields
⎯ Part 9: Portable transmitters
⎯ Part 10: Immunity to conducted disturbances in the extended audio frequency range
⎯ Part 11: Reverberation chamber

iv © ISO 2010 – All rights reserved

Introduction
Immunity measurements of complete road vehicles can generally only be carried out by the vehicle
manufacturer, owing to, for example, high costs of absorber-lined shielded enclosures, the desire to preserve
the secrecy of prototypes or a large number of different vehicle models.
For research, development and quality control, a laboratory measuring method can be used by both vehicle
manufacturers and equipment suppliers to test electronic components.
This test method is based on parts of IEC 61000-4-21 and RTCA/DO-160E.

INTERNATIONAL STANDARD ISO 11452-11:2010(E)

Road vehicles — Component test methods for electrical
disturbances from narrowband radiated electromagnetic
energy —
Part 11:
Reverberation chamber
1 Scope
This part of ISO 11452 specifies a reverberation chamber method for testing the immunity (off-vehicle
radiation source) of electronic components for passenger cars and commercial vehicles, regardless of the
propulsion system (i.e. spark-ignition engine, diesel engine, electric motor). The device under test (DUT),
together with the wiring harness (prototype or standard test harness), is subjected to an electromagnetic
disturbance generated inside the reverberation chamber, with peripheral devices either inside or outside the
chamber. It is applicable to disturbances from continuous narrowband electromagnetic fields.
The test is performed using the tuned mode method.
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.
ISO 11452-1, Road vehicles — Component test methods for electrical disturbances from narrowband radiated
electromagnetic energy — Part 1: General principles and terminology
3 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO 11452-1 and the following apply.
3.1
antenna characterization factor
ACF
ratio of the average received power to forward power obtained in the antenna characterization
NOTE See Clause B.5.
3.2
chamber characterization factor
CCF
normalized average received power over one tuner rotation with the DUT and supporting equipment present
NOTE See Clause C.3.
3.3
chamber loading factor
CLF
ratio of the antenna characterization factor to the chamber characterization factor
NOTE 1 See Clause C.4.
NOTE 2 It is a measure for the additional loading of the chamber due to the test setup including, for example, the DUT
and the support equipment.
3.4
lowest usable frequency
LUF
lowest frequency for which the field uniformity requirements are met
NOTE The LUF is determined during the characterization of the chamber in accordance with Annex B.
3.5
maximum chamber loading factor
MLF
maximum chamber loading factor for which the field uniformity has been demonstrated using the procedure
defined in Clause B.7
3.6
reverberation chamber
high Q shielded room (cavity) whose boundary conditions are changed via one or several stepped rotating
tuners
NOTE This results in a statistically uniform electromagnetic field.
3.7
support equipment
equipment associated with performing an EMC test on a DUT including (but not all inclusive) load simulator,
wiring harnesses, power supply (or batteries), DUT monitoring equipment including fibre optic interface
modules and TV camera
3.8
test bench
polystyrene block(s) with a minimum height above the ground floor of λ/4 at the lowest frequency
NOTE Typically a 1 m high support is used.
3.9
tuner
large metallic reflector capable of changing the electromagnetic boundary conditions in a reverberation
chamber as it rotates or moves
NOTE As the tuner moves, the nulls and maximums in the field change location, ensuring the device under test
(DUT) is exposed to a statistically uniform field.
3.10
working volume
volume within the reverberation chamber that contains the test bench, the DUT, the harness, the support
equipment that is located on the test bench, and the receiving antenna
2 © ISO 2010 – All rights reserved

4 Test conditions
The applicable frequency range of the test method is from LUF (see Clause B.6) to 18 GHz.
The user of this part of ISO 11452 shall specify the test severity level or levels over the frequency bands.
Typical test levels are suggested in Annex A.
Standard test conditions are given in ISO 11452-1 for the following:
⎯ test temperature;
⎯ supply voltage;
⎯ modulation;
⎯ dwell time;
⎯ test signal quality.
5 Test location
5.1 General
The test shall be performed in a reverberation chamber.
5.2 Reverberation chamber
The chamber shall be large enough to test the DUT including the test bench, the support equipment, and the
receiving antenna
...