EMC’09/Kyoto
24R3-5
International Standardization Activity on Immunity
Testing for Multimedia Equipment
Yoshiharu AKIYAMA#1 and Fujio AMEMIYA*2
#1
NTT Energy and Environment Systems Laboratories
3-1, Morinosato Wakamiya, Atsugi-shi, Kanagawa, Japan
1
akiyama.yoshiharu@lab.ntt.co.jp
*2
NTT Advanced Technology Corporation
3-9-11, Midori-cho, Musashino-shi, Tokyo, Japan
2
Fujio.Amemiya@ntt-at.co.jp
Abstract— This document describes the international
standardization activities on immunity testing for multimedia
equipment in the International Special Committee on Radio
Interference (CISPR) of the International Electrotechnical
Commission (IEC). The immunity standards specify the
minimum immunity level required for equipment and conditions
of immunity testing. Currently, CISPR 24: immunity standard
for information technology equipment such as PC and
telecommunications equipment was published. Recently, CISPR
35: immunity standard for multimedia equipment is being
discussed in CISPR subcommittee I working group 4. Mainly
differences between CISPR 24 and CISPR 35 are outlined, and
issues to be solved for publishing CISPR 35 are presented.
Key words: CISPR, immunity testing, multimedia equipment
I. INTRODUCTION
To prevent EMC problems from occurring, electromagnetic
disturbances emitted from electric and electronic equipment
and immunity to the electromagnetic environment have been
regulated by the government or voluntarily controlled by
industrial associations. The regulation or technical
requirements of emission and immunity are based on the
international standards published by the International Special
Committee on Radio interference (CISPR).
The CISPR 24: immunity standard for information
technology equipment (ITE) edition 1 was published in 1997,
and amendment 1 and 2 for CISPR 24 edition 1 were
published in 2001 and 2002, respectively [1]. The minimum
requirements for the level of immunity to electromagnetic
environments are specified in the standard. In amendment 1,
requirements for maximum acoustic demodulated levels in the
frequency ranges 10 MHz to 30 MHz and 30 MHz to 80 MHz
specified in the Annex A were modified. In amendment 2, the
definition of multifunction equipment was added to clause 3,
and new figures describing test setups of radio frequency
continuous
conducted
immunity
testing
for
telecommunication terminal equipment were added to Annex
A. CISPR 24 has been maintained in working group 3 (WG3)
of subcommittee I (SC-I) in CISPR.
On the other hand, CISPR 35: immunity standard for
multimedia equipment (MME) is being discussed in CISPR
SC-I since 2004. This is because the boundary between ITE
and audio-visual equipment is disappearing. MME is defined
as “equipment that has the function of information technology
equipment (ITE), audio, video or receiving equipment or
combinations of these functions, and which has a rated supply
voltage not exceeding 600 V” in the 2nd committee draft (CD)
of CISPR SC-I [2].
CISPR 35 covers scopes of both CISPR 24 and CISPR 20
as the definition of MME. CISPR 20 is the immunity standard
for sound and television broadcast receivers and associated
equipment [3]. CISPR 24 and CISPR 20, therefore, will be
replaced by CISPR 35 after a 5-year transition period. The
time schedule agreed for publishing CISPR 35 and
withdrawing CISPR 24 and CISPR 20 within the CISPR SC-I
Osaka meeting is shown in Fig. 1.
2008
CISPR 24 Ed.1
(published in 1997)
CISPR/I/270/CD
2010
2012
2017
CISPR 24 Ed.2
CISPR 35 Ed.1
CISPR 20 Ed.5.2
(published in 2005)
Fig. 1 Time schedule of publishing CISPR 35
(expected schedule at time of Osaka meeting 2008)
II. DIFFERENCE BETWEEN CISPR 20/24 AND CISPR 35
Immunity requirements for MME have been discussed
within CISPR SC-I on the basis of the requirements defined in
CISPR 20 and CISPR 24. On the basis of the considerations in
CISPR SC-I, the following items were agreed to for the
development of CISPR 35.
a) The framework of CISPR 35 is generally the same as that
of CISPR 24.
b) The electromagnetic environment for MME is the same as
that for ITE and broadcast receivers, so a single set of
limits is adopted by CISPR 35, which is similar to CISPR
24.
Copyright © 2009 IEICE
829
EMC’09/Kyoto
24R3-5
c) Test requirements are specified for each port considered.
d) Detailed performance criteria are defined in the Annexes.
Major differences between CISPR 20/24 and CISPR 35 are
listed in Table 1.
First, the scope of each standard is different. CISPR 20/24
covers ITE but CISPR 35 covers MME, as mentioned in
clause I.
Second, several ports such as a wired network, RF video
modulator output and antenna ports are newly employed in
CISPR 35, as shown in Fig. 2.
Equipment
RF input/output port
AC mains power port
Enclosure port
RF video modulator
output port
DC power port
Wired network port
Antenna
Fiber port
Antenna port
Signal/control port
functions. Therefore, it is useful for MME to specify
immunity test conditions and performance criteria on each
function.
Fourth, in CISPR 24, the method of immunity testing based
on IEC61000-4-3[5] is only referred for radio frequency
electromagnetic field immunity testing in the frequency range
80 MHz to 1 GHz. However, the methods based on
IEC61000-4-20 [5] and 21 [6] are also referred to in CISPR 35.
The methods of immunity testing using a transverse
electromagnetic cell (TEM cell) and reverberation chamber
are specified in IEC61000-4-20 and 21, respectively.
Equipment is deemed to comply with the immunity
requirement of CISPR 35 if it fulfills the relevant
requirements when using any of these three methods.
Fifth, testing immunity to electromagnetic waves emitted
from wireless communication systems such as mobile phones
in the 900 MHz and 1.8 GHz bands and wireless LAN in the
2.4 GHz and 5 GHz bands have been newly introduced.
Immunity requirements (electromagnetic field strength) are
specified in accordance with expected distance between MME
and wireless communication systems (see Table 2).
Table 1 Comparison between CISPR 20/24 and CISPR 35
*Italic character: difference between CISPR 20/24 and CISPR 35
Fig. 2 Examples of ports
Third, they have different normative annexes. In both
CISPR 24 and CISPR 35, general test conditions and
performance criteria are specified in the main body of the
standards. However, in CISPR 24, additional test conditions
and performance criteria are provided for specific equipment
such as telecommunication terminal equipment, copier, and
point of sales terminal for example. On the other hand, in
CISPR 35, specific test conditions and performance criteria
are provided for functions such as data processing, storage,
printing, display and so on. Examples of different types of
functions proposed in CISPR 35 are shown in Fig. 3.
Scope
Ports where
test signals
are applied.
Test signals
(basic
standard)
Movement
Sensing
Actuation
Lighting
Light
Audio
output
Sound or
TTE
Audio
input
Data
output
Data or
Transmission
Key to
Direct
Processing
Storage
&
Retrieval
Data
input
Broadcast
reception
Indirect
Scanning
Display
Video
capture
Images
(2D, 3D, Static,
Moving)
Printing
Images or Text
Annex
Fig. 3 Different types of functions
Currently, ITE or audio-visual equipment has one
representative function and immunity testing should be
performed on it. However, MME has multiple representative
CISPR 24 Ed. 1(1997)
CISPR 20 Ed.6 (2006)
ITE, Broadcast
receivers and associated
equipment
Enclosure port
Signal and telecom. port
DC power port
AC power port
Antenna input port etc.
Power frequency
magnetic field
(IEC61000-4-8)
Electrostatic discharge
(IEC61000-4-2)
Radio frequency
electromagnetic field
(IEC61000-4-3)
Electric fast transient
(IEC61000-4-4)
Surge (IEC61000-4-5)
Radio frequency
continuous conducted
(IEC61000-4-6)
Voltage dips and
interruption (IEC610004-11)
Specific equipment
Draft of CISPR 35
(CISPR/I/270/CD)
Multimedia equipment
(MME)
See Fig. 2
Power frequency
magnetic field
(IEC61000-4-8)
Electrostatic discharge
(IEC61000-4-2)
Radio frequency
electromagnetic field
(IEC61000-4-3, 20, 21)
Electric fast transient
(IEC61000-4-4)
Surge (IEC61000-4-5)
Radio frequency
continuous conducted
(IEC61000-4-6)
Voltage dips and
interruption (IEC610004-11)
Repetitive and isolated
impulsive noise
Functions
Sixth, detailed test conditions of immunity testing for
electrostatic discharge are different in CISPR 24 and CISPR
35. According to CISPR 24, 200 discharges shall be applied to
each 4 points on the equipment under test (EUT). On the
Copyright © 2009 IEICE
830
EMC’09/Kyoto
24R3-5
contrary, 10 contact discharges and 5 air discharges for both
plus and minus polarizations shall be carried out at each point
on the EUT. Furthermore, testing for lower discharge voltage
than the specified test level is not necessary in CISPR 35.
Finally, testing immunities to repetitive and isolated
impulsive
noises
are
required
for
signal
and
telecommunication ports of MME. In France, real-time IP-TV
transmission services using asynchronous digital subscriber
line (ADSL) are often suspended or degraded by block noises
appearing on the TV screen due to impulsive noises induced
into telecommunication line. Therefore, these immunity tests
are also required to reduce performance degradation of the
real-time IP-TV transmission services using ADSL [7].
Table 2 Immunity to common wireless communications
Field strength (V/m)
Test
level
1
2
3
4
5
Frequency
Separation
distance
0.2 m
0.5 m
1.0 m
1.5 m
3.0 m
900 MHz
1.8 GHz
2.4 GHz
5 GHz
27
11
6
4
2
38
15
6
4
2
9
4
2
1
1
12
5
2
2
1
The reason why the testing immunity to repetitive and
isolated impulsive noises is required for MME is that realtime IP-TV services using ADSL are often disturbed by
impulsive noises. Therefore, detailed test conditions and test
setups for DSL are specified in the draft of CISPR 35.
However, it is not clear that such disturbances have been
recognized on other telecommunication systems except ADSL.
To publish CISPR 35 including these impulsive noises testing,
the necessity of the testing for other telecommunication
systems should be discussed, and detailed test conditions and
test setups should be specified.
C. Frequency step size
According to CISPR 24, the frequency step size of the test
signal for the radio-frequency continuous conducted immunity
testing shall not exceed 1%. However, if the test level is
doubled, the frequency step size can be 4% in order to reduce
the testing time. This rule will apply to radio frequency
electromagnetic field immunity testing in CISPR 35.
However, some NCs are against the rule because most
susceptible frequencies can be missed. Therefore, this issue
has been discussed in WG4.
D. Further issue
With regard to radio-frequency electromagnetic field
a.
Calculated field strength (V/m) from GSM Mobile phones at specified
immunity and continuous conducted immunity testing, an
distances - assuming 2 W power.
b.
Calculated field strength (V/m) from WiFi / Bluetooth devices at specified
amplitude modulated tone signal is employed for test signals
distances - assuming 100 mW power
in the current immunity standard. And the test signal
c.
Calculated field strength (V/m) from WiFi devices at specified distances assuming 200 mW power.
frequency is swept within a specified range. This is because
analogue radio and television broadcast waves are considered
major electromagnetic disturbances. However, recent
III. ISSUES TO BE SOLVED TO PUBLISH CISPR 35
electromagnetic environments have become different from
those in the past due to the usage of broadband
A. Multiple test methods
communication such as wireless LANs, DSL, power line
Three alternative test methods specified in basic standards
communication (PLC) etc. Therefore, testing immunity to
IEC61000-4-3, 20 and 21 are referred for testing immunity to
such broadband disturbances will be necessary in the near
radio frequency electromagnetic field for the frequency range
future.
80 MHz to 1 GHz in CISPR 35. In CISPR Sydney meeting
Furthermore, in current radio-frequency continuous
2007, IEC61000-4-3 was employed as a reference test method
conducted immunity testing, common mode test signals are
on the basis of the agreement to decide the reference test
injected into AC mains or telecommunication lines. However,
method in SC-I. The Japanese national committee has
differential mode disturbances are injected into the AC mains
suggested to decide the reference test method, again and again.
port of the MME, in the case of coexisting PLC systems.
However, other subcommittees that publish immunity
Therefore, testing immunity to differential mode disturbance
standards for products other than MME made decisions
will also be necessary in the near future.
different from those of SC-I. The discussion on how to deal
The necessity of testing immunity to broadband and
with multiple test methods has been continued in CISPR.
differential mode disturbances has been proposed at the
After that, in the CISPR plenary meeting in Osaka 2008, it
CISPR Osaka meeting by the Japanese National Committee [8].
was suggested that the reference test method is the primary
applied one. According to this suggestion, the reference test
method can be different for each EMC test organization.
IV. CONCLUSION
However, correlation between the test methods has not been
International standardization activities on immunity testing
determined. Therefore, deciding on a common reference test
for multimedia equipment in CISPR have been presented.
method or determining the correlation between test methods to
CISPR 24: the current immunity standard for ITE and
have reproducible test results is necessary.
CISPR 35: the new immunity standard for MME were
compared, and major differences were described here. Issues
B. Testing immunity to repetitive and isolated impulsive
to be resolved to publish CISPR 35 are also described in this
noises
paper.
Copyright © 2009 IEICE
831
EMC’09/Kyoto
24R3-5
CISPR 35 was expected to be published by the end of 2009,
when the project of publishing CISPR 35 was started.
However, it will be impossible to publish it by 2009 due to so
many technical issues to be solved. About 900 comments on
the committee draft of CISPR 35 were submitted from
national committees. Technical comments were made on
about 250 of them. Therefore, at the CISPR Osaka meeting,
SC-I decided the project needs to be go back to “stage 0” on
the basis of the IEC rule, and a new work item proposal needs
to be submitted to IEC in order to restart the project as soon as
possible.
REFERENCES
[1]
[2]
[3]
[4]
[5]
[6]
[7]
[8]
CISPR24 Eition 1: “Information Technology Equipment– Immunity
Characteristics– Limits and Methods of Measurement,” 1997.
CISPR/I/270/CD: Committee draft of “Immunity standard for
multimedia products,” 2008
CISPR20 Edition 5.2: “Sound and television broadcast receivers and
associated equipment– Immunity Characteristics– Limits and Methods
of Measurement,” 2005.
IEC61000-4-3: “Electromagnetic compatibility (EMC) – Part 4:
Testing and measurement techniques– Section 3: Radiated, radiofrequency electromagnetic field immunity test– Basic EMC
publication,” 2006.
IEC61000-4-20: “Electromagnetic compatibility (EMC) – Part 4-20:
Testing and measurement techniques– Emission and immunity testing
in transverse electromagnetic (TEM) waveguides,” 2003.
IEC61000-4-21: “Electromagnetic compatibility (EMC) – Part 4-21:
Testing and measurement techniques– Reverberation chamber test
methods,” 2003.
Draft ITU-T Recommendation K.74 (K. Hnw)
CISPR/I/WG4(Amemiya)08-01: “Proposal relating to conducted
immunity test method for ac mains port by using broadband differential
mode signals,” 2008.
Copyright © 2009 IEICE
832