10 k
l
1 GHz
Far field
o
non-conductive base and support
o
l
The deciBel
Power ratio
3.6 dB
2
1.259
1.585
30 - 300 MHz
Radiated disturbance
30 - 1000 MHz
Value (±dB)
3
1.413
5.2 dB
4
1.585
2.512
5
1.778
3.162
I
6
1.995
3.981
P
Receiver contributions
Receiver sinewave accuracy
Receiver pulse amplitude
Receiver pulse repetition rate
Receiver indication
Noise floor proximity
Antenna contributions
Antenna factor calibration
AF frequency interpolation
Antenna directivity
Antenna phase centre variation
AF height deviation
Cross-polarisation
Balance
Other contributions
Cable loss calibration
Site imperfections
Measurement distance variation
Table height variation
Mismatch
Receiver VRC
Antenna VRC
Prob. dist.
Divisor
ui(y)
ui(y)
1.00
1.50
1.50
0.10
0.50
Normal
Rectangular
Rectangular
Normal (1)
Normal
2.000
1.732
1.732
1.000
2.000
0.500
0.866
0.866
0.100
0.250
0.250
0.750
2.00
0.30
0.50
1.00
0.10
0.90
0.00
Normal
Rectangular
Rectangular
Rectangular
Rectangular
Rectangular
Rectangular
2.000
1.732
1.732
1.732
1.732
1.732
1.732
1.000
0.173
0.289
0.577
0.058
0.520
0.000
1.000
0.030
0.083
0.333
0.003
0.270
0.000
0.10
4.00
0.30
0.10
-1.001
0.33
0.33
2.000
2.449
1.732
2.000
1.414
Normal
Triangular
Rectangular
Normal
U-shaped
0.003
2.668
0.030
0.003
0.501
0.050
1.633
0.173
0.050
-0.708
6.310
9
2.818
7.943
10
3.162
10.000
12
3.981
15.849
14
5.012
25.120
16
6.310
39.811
A simple rule of thumb:
18
7.943
63.096
When working with power, 3 dB is twice, 10 dB is ten times;
20
10.000
100.00
When working with voltage or current, 6 dB is twice, 20 dB is ten times.
25
17.783
316.2
30
31.62
1000
dBµV vs dBm
35
56.23
3162
dBµV
100
10,000
45
177.8
31,623
105
50
316.2
55
562.3
60
1000
65
1778
70
3162
75
5623
31,623
56,234
105
3.162 . 109
1010
To be entered
Calculated
3.162 . 105
106
1011
1012
110
120
Magnetic field strength
1.78
-46.5
0.0047
58.8
0.0059
10
3.162
15
5.623
20
10.000
0.0084
105.0
-36.5
0.0149
186.2
0.0186
-31.5
0.0265
331.5
0.0331
-41.5
0.0105
nanogauss
17.8
25
-26.5
0.590
0.0472
0.0590
30
31.62
-21.5
0.0839
1.048
35
56.23
-16.5
0.1492
1.865
0.1865
37
70.79
-14.5
0.1878
2.347
0.2347
40
100.00
-11.5
0.2652
3.315
0.3315
0.1048
dBµV at telecom port, 150 Ω ISN
5
dBµV at mains port, 50 Ω/50 µH LISN
0.0033
96 – 50 dBµV
33.1
IEC 60945
0.00265
90 dBµV
– 80 dBµV
-51.5
0.839
10.48
1.048
8.5
2.652
33.15
3.315
3.162
18.5
8.388
104.8
10.485
10.000
28.5
26.525
331.5
33.156
0.316
-1.5
60
1.000
70
80
mA/m
µgauss
nanoTesla
0.1048
90
31.6
38.5
0.0839
1.048
100
100.0
48.5
0.2652
3.315
0.3315
110
316.2
58.5
0.8388
10.48
1.048
120
1000.0
68.5
2.652
33.15
3.315
1 volt
1 millivolt
1 microvolt
1 volt per metre
1 microvolt per metre
1 microamp
1 watt
1 milliwatt
1 microwatt
-19
-9
1
11
-17
-7
3
13
-22
-12
-2
8
-28
-18
-8
2
110
100
90
80
70
Frequency GHz
IEC 60945 marine equipment QP
EN 50121-2 railway systems 750 V DC, PK
FCC Class A
FCC Class B
Disturbance power QP
0.15
MHz
1
70
CISPR 22 Telecom ports Class A QP
CISPR 22 Telecom ports Class A Avge, Class B QP
CISPR Band D
80
30
10
50
30
see extensions above 1 GHz
30
20
in 9 kHz bandwidth
20
60
54
60
54
54
Conditional testing for F > 1 GHz
CISPR 22 and FCC
40
40
6
CISPR 22 Telecom ports Class B Avge
Magnetic field limits
50
3
56
50
IEC 60945 QP
60
60
2
FCC
Class A avge
Class B avge
CISPR 14-1, CISPR 13
associated equipment)
Disturbance power Avge
1
CISPR 22 Am 1
Class A avge
Class B avge
70
0.1
10
30 MHz
100 MHz
H-field dBµA/m can be converted
to E-fielddBµV/m using a far field
assumption by adding a factor of
1 GHz
CISPR 11 group 2 Class A, QP @ 10 m
CISPR 11 induction cookers, QP @ 3 m
CISPR 15, QP @ 3 m (from LLA limits)
EN 50121-2 750V DC systems, PK @ 10 m
51.5 dB
-10
1 Gauss = 100 micro Tesla = 80 Amps/metre
Mains
input
50 Ω / 5 µH + 1 Ω
9 kHz
100 kHz
1 MHz
Impedance is measured from each phase to earth
50 Ω / 50 µH type is used for most purposes
50 Ω / 5 µH type is used for high currents and automotive
Fint
Max Ftest
< 108 MHz
< 500 MHz
< 1 GHz
> 1 GHz
1 GHZ
2 GHz
5 GHz
5·Fint or 6 GHz
(40 GHz, FCC)
Fint is the highest frequency of the
internal sources of the EUT
Principles
See EMCTLA TGN42 (from www.emctla.org ) for further guidance
EUT
VLF
LF
coastal radio telegraph
radio navigation
Omega 10 - 13 k
SF= standard frequency & time
60 kHz MSF
aircraft power
D = distress frequency
ISM = industrial, scientific & medical
Frequency
30
Wavelength 10 4 km
40
8
60
6
80
4
100 Hz
200
2
300
10 3 km
400
8
600
6
800
4
1 kHz
2k
2
thunderstorm detection
3k
100 km
4k
8
6k
6
8k
4
ISN
10 kHz
20 k
2
30 k
10 km
40 k
8
LORAN C,
Decca
ISN
L
Equipment
under test
short, direct strap to
ground reference plane
Alternative measurement options when ISNs are not suitable
SF
60 k
6
80 k
4
100 kHz
D
200 k
2
SF
cordless phones
150 k
300 k
1 km
400 k
8
1.64 - 1.78 M
500 k
600 k
6
800 k
4
1 MHz
2.182 M
2M
2
2.5 M
(2) For screened cables: method
C.1.2 using current probe or
voltage measurement
10 cm ferrite
(3) For other cables: method
C.1.3 using both current and
voltage probes
I
I
V
D
measurement output (50 )
V
Key characteristics

3M
100 m
D
D
8.4 M
6M
6
Measurement distance is taken
from the boundary of the EUT
to the reference point on the
antenna
both polarisations tested
rotate to maximise level
Frequency MHz
Measured power = indicated value (dBµV) + correction factor dB
Power in dBpW = voltage in dBµV across 50 Ω - 17 dB
turntable
vary height
over 1 to 4 m
EUT
> 40 cm 80 cm
mains
Cable should drape to ground plane
well back from rear of antenna
to measuring instrument
ground plane
Normalised site attenuation
•
•
35
30
Receiver noise
floor, 6 dBµV
25
AF CBL6111C,
dB/m
20
10 m N-N cable
loss, dB
Associated
equipment (AE)
dB
•
15
System noise
floor, dBµV/m
10
Class B limit
dBµV/m at 10 m
uncontrolled
impedance
Site attenuation is the overall loss between two antennas on a given open field test site, spaced at the measuring distance.
According to CISPR 16-1-4 and CISPR 22, the measured site attenuation of a site used for compliance tests must be within ±4 dB
of the theoretical for an open site.
Site attenuation can be measured with a pair of broadband antennas, a spectrum analyser and tracking generator (see diagram).
For test sites which do not conform to the open area requirements, a set of site attenuation measurements are needed with the
transmit antenna placed at several points over the test volume (see CISPR 22 annex A and CISPR 16-1-4).
The measured value VSITE is the maximum recorded over the receiving antenna height scan at each frequency, and VDIRECT
is the value recorded when the antenna cables are connected to each other. AFT and AFR are the respective
antenna factors. The NSA is then given by
•
•
AN(dB) = VDIRECT - VSITE - AFT - AFR
D
8M
4
15 M
●


CB
D
am 21-21.45 M
SF
20 M
SF
Longitudinal conversion loss (LCL):
defined in product standards,
implemented by Zunbal in adapter
Common mode impedance at EUT port:
150 ±20 , phase 0º ±20º
Isolation from AE port: > 35 - 55 dB from
0.15 - 1.5 MHz, > 55dB from 1.5 - 30 MHz
Voltage division factor: approx. 9.5 dB
Frequency, MHz
10
13.56 M
10 MHz
D
1000
VMEAS (dBµV)
VT Z
LCL = 20·log(V T /E L )
EL
Z = 100
=
direct wave
20
Height varied
over 1 to 4 m
during test
typ.
25 M
military aero & satellite
land mobile (PMR)
cellular
phones
470 M
amateur
SF
satellite
amateur
land mobile (PMR)
amateur
144 146 M
430 440 M
Bands IV/V
TV broadcast
853 M
960 M
1.215 G
30 M
10 m
fixed
radio
access
land mobile
8
60 M
6
80 M
4
100 MHz
200 M
2
300 M
400 M
1m
8
600 M
6
800 M
3.6 G 4.2 G
fixed links
L-band
4
1 GHz
2G
2
10 m
horizontal
vertical
5.0
0.0
tracking generator
spectrum analyser
-5.0
Geometries for broadband antennas:
Geometries for broadband antennas:
Transmitting antenna height: 1m
Transmitting
antennaantenna
height: height
1 m scan: 1 - 4m
Receiving
Receiving Horizontal
antenna height
scan: D
1–
4m
separation
between
antennas 3m, l0m or 30m
Horizontal The
separation
D between
antennas
3 m, antenna
10 m or 30
m
curves are
normalized
to exclude
characteristics
CISPR 16-1:1999
The curvesFrom
are normalized
to exclude antenna characteristics
Source: CISPR 16-1-4, CISPR 22
-10
3m
horizontal
vertical
-15
-20
-25
SHF
radar
satellite downlinks
radio altimeters
4.3 G
40M
10
100
1000
MHz
Electromagnetic spectrum - RF emissions
radar
1.35G 1.53G 1.7G
aero DME
156 M 165 M
Band II vhf/fm
87.5 M broadcast
radar
ground reflected
wave
HT = 1 m
15
30
UHF
maritime
108 M
136 M
comms
aero
27 28 M
am 28-29.7 M
E (dBµV/m) + AF (dB/m) + A (dB)
VMEAS is the measured voltage at the test receiver, A is the cable and other losses
between the antenna and receiver
Theoretical normalised site
attenuation versus frequency
25
attenuator
pad for
matching
27.12 M
20 M
2
100
The system noise floor as shown above – the smallest signal that can be detected – is
given by the receiver's own noise floor corrected by A and AF.
The antenna factor is initially provided by the manufacturer but can be re-calibrated at
any time by a specialist calibration house, using a number of methods. CISPR has
standardized on the free space calibration in which the antenna is assumed not to interact
with its surroundings, e.g. the EUT and the ground plane. Actual antenna factors will vary
with proximity to other objects and also between vertical and horizontal polarization; these
variations should be accounted for in the measurement uncertainty budget.
Z/4
ISM
16.8 M
ISM
30
measurement distance D
0
Using the antenna factor
LCL describes mode conversion, i.e the degree to
which a poorly balanced termination develops an
unwanted transverse (differential) signal when
by a longitudinal (common mode) signal, as in the
measurement circuit below
radio
astronomy
SF
12.5 M
Theoretical site attenuation characteristics versus frequency
5
VHF
am 14-14.35 M
10 M
6.3 M
4M
8
amateur 7-7.1 M
SF
4.2 M
15
Example system noise floor
ISN
100
ferrite
(optional)
Notes:
● for method (2) the common mode impedance Z CMto the AE side of the
150 resistance should be confirmed as >> 150
● for method (3) both current and voltage limits should be satisfied; if
these are exceeded, at spot frequencies measure Z CM and set it to
150 by adjusting ferrites, then apply current limit only ( method C.1.4)
energy saving
lamps 2.6 M
-2
40
AE side
Z unbal
50
5M
17
Emissions measuring antennas are characterised by their antenna factor AF. This gives the
conversion between the field strength E they are measuring and their output voltage:
CVP
connection
to outside
of screen
100
3.5-3.8 M
0
measurement distance L = 3 or 10 m
receiver
50 Ω
EUT side
(1) The ISN may be replaced by a CDN according to IEC 61000-4-6:
method C.1.1
amateur
1.8-2 M
19
Generic circuit for two unscreened balanced pairs
short-wave broadcasting
amateur
21
+2
Antenna factors
external limiter
CFL 9206
50
HF
1.6 M
+4
E
100
aero, maritime & land mobile and fixed
500 k
a+2 m
d = maximum EUT dimension
a = maximum antenna dimension
(1.6 m for BiLog)
Method: select frequencies to be measured, at each
frequency find maximum with respect to height scan,
polarization and turntable rotation.
Record level, frequency and polarization of the six
highest measurements of those disturbances greater
than (Limit – 20 dB).
N
VN
current or voltage
measurement
auxiliary
clamp
or ferrites
measuring
clamp
minimum ground plane
Typical calibration curve
coupling and decoupling may be
separate or combined
EUT
cable under test
to mains
supply or
other
termination
d+2 m
2⋅L
measurement
MF
long-wave broadcasting
raceway for clamp
non-conducting table
The telecom port Impedance Stabilising Network
AE
medium-wave broadcasting
mains power
EUT
0.4 m min (CISPR 14-1)
0.8 m min (CISPR 16-2-2)
L
Radiated emissions test setup
according to CISPR 22
secondary
AMN/LISN
bonded to ground
reference plane *
antenna
EUT
80 cm
> 40 cm
if possible
aero nav NDB
For dwell time of 5 time constants, half-bandwidth frequency spacing
area free of reflecting objects
(5 m + clamp length) min
HPF
Z CM = 150
controlled
external
impedance
to ground
The ISN is adapted for LCL
with Zunbal according to the
category (ISO/IEC 1 1801)
of the cable to be used
300 kHz
1.67 · 107
to spectrum analyser
or test receiver
distance varied for maximum reading
CISPR 22: Telecom port testing
The basic layout for the conducted test is the same as for measuring
mains emissions
9 kHz
1.25 · 106
Site must meet the normalised site attenuation requirements
of CISPR 16-1-4 (see below).
Alternative test sites (e.g. semi-anechoic chambers)
can be used if they meet the ±4 dB NSA requirement
over five points.
ferrite rings
(interference current absorbers)
Absorbing clamp test setup
Applying 230 V 50 Hz ac across approximately 12 µF creates around 0.9 A of earth current,
continuously while the LISN is connected: a LISN cannot be used with an earth leakage protected supply
NB differences
in detector type
and measurement
distance
induction heating, mains signalling communication and control, induction loop systems, metal detectors
It follows the ITU Region 1 allocations (Europe, Middle East, Africa
and CIS); other ITU Regions may have different allocations
2 or 3 ferrite rings
Warning: high circulating currents - ensure a positive connection to safety earth!
Test setups
200 Hz
1.89.104
Standard open area test site (OATS)
Lead to be
measured
common mode
interference current
5Ω
9 kHz high pass filter
advisable but not mandatory
30 MHz
10 MHz
CISPR Band B
ELF
EUT
80 cm to
ground
reference
plane
E
150 kHz
1
10 kHz
120 kHz
1 ms
550 ms
43.5 dB
74 mins
to spectrum
analyser or
test receiver
Current
transformer
50 Ω
50 Ω / 5 µH + 50 Ω
9 kHz
1 ms
160 ms
30 dB
89 mins
Radiated test setup
ferrite rings (sheath surface current absorbers)
0.25 µF
8 µF
10 Ω
200 Hz
45 ms
500 ms
24 dB
64 mins
Absorbing clamp setup
Absorbing clamp construction
L
10
30 to 1000 MHz
to CISPR 16 measuring receivers.
50 µ H
250 µH
4 µF
Frequency range
0.15 to 30 MHz
ment for measuring EMI in the frequency range 9 kHz to 1 GHz. All commercial standards refer
N
50 Ω / 50 µH down to 150 kHz
Radiated emissions
methods – measuring apparatus”, specifies the characteristics and performance of equip-
network duplicated for each phase and/or neutral
50 Ω
Fail
IEC/CISPR 16-1-1, “Specification for radio disturbance and immunity measuring apparatus and
±20% tolerance
IEC 60945 marine equipment, QP @ 3 m
CISPR Band A
1
Good shielding, filtering, layout and grounding help, but can never be perfect, so testing is always needed
50 Ω/50 µH + 5 Ω LISN circuit
according to CISPR 16-1-2
100
Pass
9 to 150 kHz
Bandwidth
τ /τ
D C
All conducting parts (PCB, wires and chassis) of the product contribute to the process, and common mode
paths are usually the most important
Conducted emissions test layout for tabletop equipment according to CISPR 22
LISN impedance
according to CISPR 16-1-2
Fail
Peak
At lower frequencies these currents radiate more effectively from long cables, and so measurement of
voltage (B) or current (C) on the cable is easier
** rules apply for system EUTs with multiple mains cables: each cable
terminated in a standard plug or not connected via a host unit is tested separately
-20
This display of the electromagnetic spectrum lists the main services
in the UK according to the UK Frequency Allocation Table 2002
Noise voltages also appear on mains and signal cable ports and cause common-mode currents (on all
wires together) which radiate directly from the cables (AB), (AC)
Ground reference plane(s) at least 2 x 2 m, and at least
0.5 m beyond the projection of the test arrangement
* LISNs may alternatively be bonded to vertical plane
10
0
VN and IN create radiated E and H fields which travel away from their source (A)
associated
equipment
> 80 cm
40 cm to vertical
reference plane
bonded to ground
reference plane * HORIZONTAL GROUND REFERENCE PLANE
N
Bandwidth
Charge time
Discharge time
Overload factor
Sweep duration1
Internal circuit operation creates noise voltages V N and currents IN within the circuit and chassis structure:
sources include SMPS, HF clocks and digital operation, video signals, electro-mechanical switching
by Teseq
High frequency extensions
All measurements above 1 GHz, dBµV/m at 3 m
VHF limits
40
10 kHz
CISPR 11 Group 2 > 100 A QP
QP = quasi peak detector, Avge = Average
detector, PK = peak detector; average limits
shown dashed, other limits apply QP unless
stated; if the average limits are met using
the QP detector, a further average
measurement is unnecessary
90
50
H-field, dBµA/m
CISPR Class A
CISPR Class B
CISPR 11 Group 2 Class A QP
CISPR Band C
60
1 m mains
cable, excess
bundled as
shown **
Main
AMN/LISN
N
Quasi - Peak
cables bundled to hang
> 40 cm above horizontal plane
and run 40 cm from vertical plane
I/O cable
> 40 cm
for external
connection
< 40 cm
refers to
dBV
dBmV
dBµV
dBV/m
dBµV/m
dBµA
dBW
dBm
dBµW
600
-138
-128
-118
-108
-98
-88
-78
-68
-58
-48
-38
-28
-18
-8
2
150
-132
-122
-112
-102
-92
-82
-72
-62
-52
-42
-32
-22
-12
-2
8
75
-129
-119
-109
-99
-89
-79
-69
-59
-49
-39
-29
-19
-9
1
11
suffix
result < QP limit?
non-conductive table
unconnected
cable
to receiver or
spectrum analyser
via limiter
Power in dBW
0
10
20
30
mV/m
50
50
-127
-117
-107
-97
-87
-77
-67
-57
-47
-37
-27
-17
-7
3
13
dBV
©
120
110 dBµV
1.0
9 kHz
0
50 kHz 150 kHz
picoTesla
EN 55015
EN 55011
Ind. cookers
picogauss
µA/m
at least 80 cm between
closest point of LISN
and boundary of EUT
Y
Parameter
Peripheral
EUT
N
CISPR 16-1 Instrumentation characteristics
32.5 - 3.5 – 2.5 + 46.0 = 72.5 dBµV = 12.5 dBmV = 4.2 mV
Common suffixes
Conducted limits
130
Frequency
dBµA/m
140
Low frequency extensions
µV/m
rear of EUT to be flush
with rear of table top
Emissions limits: Limit values for the common commercial standards
Field strength conversion table
dBµV/m
=
Power in dBm for impedance ZΩ
-20
-10
0
10
20
30
40
50
60
70
80
90
100
110
120
3.162 . 107
108
3.162 . 108
109
691-003B
dB) into an amplifier of gain 200 (46 dB) will result in an output of:
Vout
10 cm
Maximize at
each freq
Flowchart for use of detectors
All trademarks recognised.
transducer with conversion factor 0.67 (–3.5 dB) and a cable with attenuation loss 0.75 (-2.5
3.162 . 106
107
17,783
95
are transformed into simple additions. For example, a signal of 42 µV (32.5 dBµV) fed via a
N
result < QP limit?
measurement requires that all radiated emissions are maximized
VERTICAL GROUND REFERENCE PLANE
hand-operated devices
placed as for normal
useage
QP detector
result < avge limit?
X is a margin to allow for expected difference due to maximization procedure; a fully compliant
Conducted test setup and LISN
© 2009 Teseq
Specifications subject to change
without notice.
Expressing values in dB means that multiplicative operations (such as attenuation and gain)
3.162 . 105
106
10,000
100
Electric field strength
@
2.512
90
6.747
2.597
5.19
=
=
8
85
Normal
Normal, k = 2.0
log-1 (dBV/20) volts
log-1 (dBA/20) amps
log-1 (dBW/10) watts
=
5.012
80
Combined standard uncertainty
Expanded uncertainty
V
2.239
40
Teseq AG
Nordstrasse 11F
4542 Luterbach
Switzerland
Tel: +41 (0)32 681 40 40
Fax: +41 (0)32 681 40 48
N
Conducted emissions
90 + 10 log (Z) + P(dBm)
7
2
0.750
0.010
0.063
=
result < QP limit - X?
QP detector
Pass
20 log (V1/V2) or 20 log (I1/I2)
Actual voltage, current or power can be derived from the antilog of the dB value:
4.5 dB
Example: 200 MHz to 1 GHz, log periodic antenna, vertical polarisation, distance = 3 m
Contribution
V(dBµV)
Y
N
result < QP limit?
Average detector
Conversion between voltage in dBµV and power in dBm for a given impedance Z ohms is
1.995
Measurement uncertainty budget for radiated measurement
Y
3G
10 cm
4.8 G
aero
MLS
5.1 G
4G
8
doppler radar
satellite uplinks
5.85 G
7G
ISM, RTTT
5.8 G
6G
6
8G
4
EHF
radar
radar
DBS
HIPERLAN 17.2 G
0.15 - 30 MHz
result < avge limit?
aero weather
radar 9.375 G
1
1.259
=
Create table
of frequencies
N
10
HIPERLAN 5.2 G
1.122
1.122
Y
constant impedance is given by
dB
Peak detector
Create table
of frequencies
far field
satellite-mobile downlinks 1530-1559 M
GPS 1575.4 M
mobile-satellite uplinks 1626-1660 M
PCN/GSM mobile-base 1720-1785 M
PCN/GSM base-mobile 1815-1880 M
DECT cordless phones 1880-1900 M
UMTS (3G) 1920-1980 uplink
UMTS (3G) 2110-2170 downlink
ISM, microwave ovens, tags,
wireless LANs, Bluetooth 2450 M
1.059
4.0 dB
Peak detector
1
GPS1227.6 M
on EMC measurement uncertainty.
Disturbance power
0.5
9 - 150 kHz
lower reading still. Continuous signals will show the same value with all types of detector.
transition region
10
ATC SSR transponders 1030,1090 M
detail and UKAS publication LAB 34 for more guidance
1.000
will give a lower reading for low pulse rate impulsive signals, while the average detector will give a
near field
Correction
factor dB
Insertion
loss dB
(mains port)
antenna at 3 m. See CISPR 16-4-1 and 16-4-2 for more
1.000
hospital pagers 31.75 M
radiated test with a vertically polarised log periodic
0
peak limits
20 dB higher
Conducted disturbance
0.501
Power is proportional to voltage squared, hence the ratio of voltages or currents across a
10 k
1k
result < avge limit?
RF emission testing
10 log (P1/P2)
E field, dBµV/m, normalised (1/d) to 10 m
indicates how this was derived as an example for the
0.708
=
e
Y
aero ILS glide path 329-335 M
UCISPR
-3
dB
nc
da
How does a product emit RF?
Digital audio broadcast 217-230 M
0.251
u
so
i
rce
e
mp
Y
EPIRBs 243 M
0.1
0.501
100
Y
ERMES pagers 169.4-169.8 M
radio mics 173-175 M
0.3162
-6
10
1
Distance from source d, normalized to λ/2π
aero ILS marker beacon 75 M
-10
Originally the dB was conceived as a power ratio, given by
model aircraft 35.1 M
cordless audio 37 M
ISM 40.68 M
vehicle & security alarms 47.3 M
CT1 cordless phones 47.45-47.54 M
radio mics 48.4-48.5 M
on-site pagers 49-49.5 M
radio mics 52.85-52.95 M
The product does not comply if any measurement exceeds the limit.
and compared to the limit as before.
referred to 1 µV, dBm is referred to 1 mW.
0.01
0.1
-20
If ULAB is greater than UCISPR, then the measurements are increased by a factor (ULAB — UCISPR)
The deciBel (dB) represents a logarithmic ratio (base ten) between two quantities and is
-50
E ∝ 1/d, H ∝ 1/d
0.1
unitless. If the ratio is referred to a specific quantity this is indicated by a suffix, e.g. dBµV is
The product complies if no measurement exceeds the limit;
The table to the right gives UCISPR, and that below
Within the near field, field strength is inversely proportional to the
square or cube of distance from the source, and the ratio and
direction of the electric and magnetic field vectors is complex and
generally unknown
TETRA 380-400 M
TETRA 410-430 M
short range devices 433.92 M
2-way radios (license-free) 446 M
wide area pagers 454-454.8 M
SRDs & local pagers 458.5-459.5 M
telemetry 463-464 M
Voltage or
current ratio
40 cm
dB
test and how to use it. If the laboratory’s calculated uncertainty ULAB is less than or equal to UCISPR as given below, then:
-40
Plane wave
Zo = 377 Ω
Magnetic field
predominates
E ∝ 1/d2, H ∝ 1/d3
100
1 of a series of wallchart guides
> 80 cm
n
o
Impedance Ω
l
o
E & OE: Whilst great care has been taken in preparing this data, Teseq AG cannot be responsible in any way for any errors or omissions.
Standards are subject to change and it is strongly recommended that before any tests are carried out, the latest issue of the standard is obtained from the relevant standards body.
l
u
low
10
average 0.15 - 30 MHz
The peak detector will always give the highest reading on all types of disturbance. The QP detector will give a lower reading for low pulse rate
100
1.0
nc
e
quasi-peak 30 MHz - 1 GHz
-30
The peak detector will always give the highest reading on all types of disturbance. The QP detector
Distance from source (m)
Large loop antenna (LLA or Van Veen loop)
for magnetic field measurements 9 kHz - 30 MHz
from CISPR 15 annex B
o
0.1
da
-20
dB
l
o
Near field
rce
i
Repetition frequency of pulsed interference (Hz)
λ/2π
1 MHz
ou
quasi-peak 0.15 - 30 MHz
Region of
unknown field
impedance E/H
0.5 m
to test receiver
EN 60945: 2002: Marine navigation and radio-communication equipment and systems
Measurement
10 MHz
mains
coaxial
3-way
switch
aero nav + ILS localizer 108-118 M
aero comm 118-136 M
(EPIRBs121.5 M)
pagers 138M
pagers 153-153.5 M
maritime distress 156.8 M
l
ferrite
o
o
hs
1000
100 MHz
-10
Electric field predominates
E ∝ 1/d3, H ∝ 1/d2
mp
e
Wave impedance, Ω
l
o
CISPR 16-4-2: 2003, Uncertainty in EMC measurements, specifies how to calculate the uncertainty budget for an emissions
l
hig
EUT
Measurement uncertainty CISPR 16-4-2
l
Within the far field, field strength is inversely proportional to the
distance from the source, the electric and magnetic field vectors
are orthogonal to each other and the direction of propagation, and
their ratio is constant and defined by the impedance of free space
current probe
(dBpW on leads, using absorbing clamp, CISPR 13/14-1)
EN 50091- 2: 1995: Uninterruptible power systems
peak
Relative output (dB)
l
l
o
0
according to Maxwell's field equations
resistively
loaded slit
l
Relative output versus PRF for CISPR 16 detectors
The near field/far field transition
2 m diameter
radio mics 854-860 M
CT2/CAI cordless phones 864-868 M
ou
CISPR 16-1 Instrumentation
Electromagnetic field
ET ACS mobile-base 872-890 M
GSM mobile-base 890-915 M
ET ACS base-mobile 917-935 M
GSM base-mobile 935-960 M
BiLog
www.teseq.com
Mains port conducted RF 150 kHz – 30 MHz, radiated
RF 30 MHz – 1000 MHz. The reference standard
for the test methods quoted is CISPR 16-1 and
CISPR 16-2
H-field loop
Magnetic field test
Note: Most product standards reference one or other of the above to define the measurement methods for emissions. Those which define their own emissions test methods are
In the far field, with Zο = 377 Ω
Scope and required tests and equipment for the common commercial standards
Standards
Electrical equipment intended for
professional, industrial process and
educational use, for measurement
and test, control or laboratory
EN 61326: 1997 + A1: 1998,
A2: 2001 + A3: 2003
(Equivalent to
IEC 61326: 1997)
ISNs
Scope
Required tests
LISN
Scope
Required tests for RF emissions
All apparatus intended for use Refers to EN55022, EN55014 and EN60555 for
Electrical
and electronic
apparatustests.
Refers
to EN 55022
and EN
for tests.conRadiated
in
the domestic,
commercial
n
Radiated
emissions
on55014-1
the enclosure,
intended
for use environin residential,ducted
emissions
on harmonics
the enclosure;
conducted
RFport
including n
and
light industrial
RF and
on the
AC mains
commercial
andnolight-industrial
discontinuous on the AC mains port; conducted RF
ments
for which
productenvironments
forexistwhich no using a current probe on signal, control, DC power
specific
standards
dedicated product or product- and other ports
family
standard
exists environ- Refers to EN55011 for enclosure radiated and AC
As
above
for industrial
ments
EN50081-2: 1993
mains conducted tests
As above for industrial environ- Refers to EN 55011 for enclosure radiated and AC
EN 61000-6-4:2001
n
ments
mains
conducted
tests;
discontinuous
conducted n
(Equivalent to
Equipment
designed to gener- Mains
terminal
voltage
150kHz–30MHz
using
emissions
on radiated
the AC mains
occurring on
more
than
IEC
61000-6-4:
1997)
ate RF energy for industrial,
EN55011:
1991
CISPR-16
LISN;
field port
30– 1000MHz
test
n
5 times
a minute
subject
to modified
scientific and medical (ISM) pur- site
(Equivalent to CISPR 11:
or in situ
(Classare
A only).
Group
2 Classlimits
A limits
poses, including spark erosion apply down to 150kHz; limits for 11.7–12.7GHz
1990 with modifications)
Mains
terminal voltage 150 kHz – 30 MHz using
EN
55011:
1998
+ A1:11:
1999
+ Equipment designed to generate RFalso
(3rd
edition
CISPR
1997,
presented
energy for industrial, scientific and CISPR-16 LISN; radiated field 30 – 1000 MHz on n
A2:
to 2002
be published as EN)
medical (ISM)
purposes,
including test site or in situ (Class A only). Group 2 Class A
(Equivalent to CISPR 11: 1997 Broadcast
sound
and television
spark erosion
limitsterminal
apply down
to 150kHz–30MHz
150 kHz; A1: 1999
introduces
with
modifications)
receivers
and associated equip- Mains
EN55013:
1990
voltage
using
emissions
limits
between
1 and voltage
18 GHz from Group 2
ment, e.g. audio equipment,
(Not equivalent to CISPR
CISPR-16
LISN;
antenna
terminal
n
Class B > 400radiated
MHz
VCRs, CD players, electronic
13)
30–1000MHz,
field 80–1000MHz for LO
organs
and harmonics, disturbance power for associated
Broadcast sound and televisionequipment
Mains terminal
voltage on
150leads
kHz –>30
MHz using CISPREN 55013: 2001 + A1: 2003
30–300MHz
25cm
(Equivalent to CISPR 13: 2001 receivers and associated equip- 16 LISN; antenna terminal voltage 30 – 1000 MHz, n
ment intended
to main
be connected
radiated
field voltage
80 – 1000
MHz for LO and
harmonics
with modifications)
Appliances
whose
funcMains
terminal
150kHz–30MHz
using
directly
these orbytomotors
generateCISPR-16
and Class
B limits
for others,interference
disturbanceover
power for
tions
aretoperformed
EN55014-1: 1993
LISN;
discontinuous
or reproduce
or visualthis
associated
equipment
30 – 300
MHz on leads
> 25 cm;
switching oraudio
regulating
(Equivalent to CISPR 14-1: and
frequency
range where
appropriate;
disturinformation
A1: 2003
adds
methods
receivers
devices,
e.g. household appli1993)
bance
power
30–
300MHzfor
ondigital
all leads
n
ances, electric tools etc
EN 55014-1: 2000 + A1: 2001 Appliances whose main functions Mains terminal voltage 150 kHz – 30 MHz using
arelighting
performed
by motors
+ A2: 2002
All
equipment
and aux-and CISPR-16 LISN; discontinuous interference over this n
switching
regulating
devices,Fluorescent
frequency lamp
rangeluminaire
where insertion
appropriate;
(Equivalent to
iliaries
withora primary
function
loss disturbance
150–
e.g.generating
householdand/or
appliances,
electric1605kHz;
power 30
300 MHz
on equipment,
all leads; A1:mains
2001 teradds an
CISPR
14-1: 2000)
of
distributEN55015:
1996
all –other
lighting
toolslight
etc.for illumination, and
extravoltage
EN 55022
radiated test
onlyCISPR-16
for toys LISN;
ing
(Equivalent to CISPR 15:
minal
9kHz–30MHz
using
lighting part of multi-function
1996)
HF lamps, radiated magnetic field 9kHz–30MHz
n
All lighting equipment andusing
Fluorescent
loss 150
– 1605
EN 55015: 2000 + A1: 2001 + equipment
Van Veenlamp
loop,luminaire
relaxed insertion
levels between
2.2
auxiliaries with a primary functionand
kHz;
all other lighting equipment, mains terminal n
A2: 2002
3MHz
of generating
and/or distributing voltage 9 kHz – 30 MHz using CISPR-16 LISN; HF lamps,
(Equivalent to CISPR 15: 2000) Information
Technology
light for illumination,
andprimary
lightingMains
radiated
magnetic
field150kHz–30MHz
9 kHz – 30 MHz using
Equipment
(ITE), whose
terminal
voltage
usingVan Veen
part of multi-function
loop, relaxed
between
2.2 1000MHz
and 3 MHzon test
function
is data entry,equipment
storage, CISPR-16
EN55022: 1994
LISN; levels
radiated
field 30–
display, retrieval, transmission, site
(Equivalent to CISPR 22:
Information Technology
Mains terminal voltage 150 kHz – 30 MHz using
EN
55022: 1998 + A1: 2000 + processing,
switching orEquipment
control
1993)
n
(ITE), whose primary function is CISPR-16 LISN; radiated field 30 – 1000 MHz on test
A2: 2003
(Equivalent to CISPR 22: 1997) data entry, storage, display, retrieval, site; conducted current or voltage from 150 kHz to n
transmission, processing, switching 30 MHz at telecommunication ports; further tests are
or control
being introduced in a later edition from 1 to 6 GHz
Standard
Standard
EN50081-1: 1992
EN 61000-6-3:2001 + 11:2004
(Equivalent to
IEC 61000-6-3: 1996)
Abs. clamp
All EUTs with Telecom Ports
BiLog
Some EUTs
All mains powered EUTS
H-field loop
o
n
u
Current probe
All EUTs
LISN
l
11.7 G 12.5 G
fixed radio
access
10.1–10.6 G
10 GHz
satellite
satellite
radio astronomy
oxygen resonance Road transport &
traffic telematics
(RTTT) 76-77G
water vapour resonance
ISM
24.125 G
20 G
2
microwave spectroscopy
30 G
1 cm
40 G
8
60 G
6
80 G
4
100 GHz
200 G
2
300 G
1 mm