Cable networks for television signals, sound signals and interactive services - Part 2-1: Electromagnetic compatibility measurements

Standards and deliverables of EN 60728 series deal with cable networks including equipment and associated methods of measurement for headend reception, processing and distribution of television and sound signals and for processing, interfacing and transmitting all kinds of data signals for interactive services using all applicable transmission media. These signals are typically transmitted in networks by frequency-multiplexing techniques. This includes for instance • regional and local broadband cable networks, • extended satellite and terrestrial television distribution systems, • individual satellite and terrestrial television receiving systems, and all kinds of equipment, systems and installations used in such cable networks, distribution and receiving systems. The extent of this standardization work is from the antennas and/or special signal source inputs to the headend or other interface points to the network up to the terminal input of the customer premises equipment. The standardization work will consider coexistence with users of the RF spectrum in wired and wireless transmission systems. The standardization of any user terminals (i.e. tuners, receivers, decoders, multimedia terminals etc.) as well as of any coaxial, balanced and optical cables and accessories thereof is excluded.

Kabelnetze für Fernsehsignale, Tonsignale und interaktive Dienste - Teil 2-1: Messungen der elektromagnetischen Verträglichkeit

Kabelska omrežja za televizijske in zvokovne signale ter interaktivne storitve - 2-1. del: Meritve elektromagnetne združljivosti

Standardi in izsledki skupine standardov EN 60728 obravnavajo kabelska omrežja, vključno z opremo in povezanimi metodami za merjenje sprejema glavne sprejemne postaje, obdelavo in distribucijo televizijskih in zvokovnih signalov ter za obdelavo, povezovanje in oddajanje vseh vrst podatkovnih signalov za interaktivne storitve prek vseh primernih prenosnih medijev. Ti signali se v omrežjih običajno prenašajo s tehnikami multipleksiranja frekvenc. To na primer vključuje • regionalna in lokalna širokopasovna kabelska omrežja, • razširjene satelitske in prizemne televizijske distribucijske sisteme, • posamezne satelitske in prizemne televizijske sprejemne sisteme ter vse vrste opreme, sistemov in naprav, uporabljene v tovrstnih kabelskih omrežjih, distribucijskih in sprejemnih sistemih. To standardizacijsko delo med drugim zajema antene in/ali posebne vhode virov signalov v glavno sprejemno postajo ali druge vmesniške točke do omrežja vse do vhodnega terminala opreme v prostorih stranke. To standardizacijsko delo bo upoštevalo soobstoj uporabnikov radiofrekvenčnega spektra v ožičenih in brezžičnih prenosnih sistemih. Standardizacija poljubnih uporabniških terminalov (tj. uglaševalnikov, sprejemnikov, kodirnikov, večpredstavnostnih terminalov itd.) in poljubnih povezanih koaksialnih, simetričnih in optičnih kablov ter opreme je izključena.

General Information

Status
Published
Publication Date
19-Oct-2014
Current Stage
6060 - National Implementation/Publication (Adopted Project)
Start Date
17-Sep-2014
Due Date
22-Nov-2014
Completion Date
20-Oct-2014

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SLOVENSKI STANDARD
SIST-TP CLC/TR 50083-2-1:2014
01-december-2014

Kabelska omrežja za televizijske in zvokovne signale ter interaktivne storitve - 2-1.

del: Meritve elektromagnetne združljivosti

Cable networks for television signals, sound signals and interactive services - Part 2-1:

Electromagnetic compatibility measurements

Kabelnetze für Fernsehsignale, Tonsignale und interaktive Dienste - Teil 2-1: Messungen

der elektromagnetischen Verträglichkeit
Ta slovenski standard je istoveten z: CLC/TR 50083-2-1:2014
ICS:
33.060.40 Kabelski razdelilni sistemi Cabled distribution systems
SIST-TP CLC/TR 50083-2-1:2014 en,fr,de

2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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SIST-TP CLC/TR 50083-2-1:2014
TECHNICAL REPORT CLC/TR 50083-2-1
RAPPORT TECHNIQUE
TECHNISCHER BERICHT
September 2014
ICS 33.060.40
English Version
Cable networks for television signals, sound signals and
interactive services - Part 2-1: Electromagnetic compatibility
measurements
To be completed Kabelnetze für Fernsehsignale, Tonsignale und interaktive
Dienste - Teil 2-1: Messungen der elektromagnetischen
Verträglichkeit
This Technical Report was approved by CENELEC on 2014-07-28.

CENELEC members are the national electrotechnical committees of Austria, Belgium, Bulgaria, Croatia, Cyprus, the Czech Republic,

Denmark, Estonia, Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia,

Lithuania, Luxembourg, Malta, the Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland,

Turkey and the United Kingdom.
European Committee for Electrotechnical Standardization
Comité Européen de Normalisation Electrotechnique
Europäisches Komitee für Elektrotechnische Normung
CEN-CENELEC Management Centre: Avenue Marnix 17, B-1000 Brussels

© 2014 CENELEC All rights of exploitation in any form and by any means reserved worldwide for CENELEC Members.

Ref. No. CLC/TR 50083-2-1:2014 E
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Contents page

Foreword ................................................................................................................................ 4

1 Scope .............................................................................................................................. 5

1.1 General ................................................................................................................... 5

1.2 Specific scope of CLC/TR 50083-2-1 ...................................................................... 5

2 Normative references ....................................................................................................... 6

3 Term, definitions, symbols and abbreviations ................................................................... 6

3.1 Terms and definitions .............................................................................................. 6

3.2 Symbols ................................................................................................................ 10

3.3 Abbreviations ........................................................................................................ 11

4 Considerations on EMC measurements .......................................................................... 11

4.1 General ................................................................................................................. 11

4.2 General EMC measurement considerations ........................................................... 12

4.3 Envelope (peak) detection mode ........................................................................... 13

4.4 Quasi-peak detection mode................................................................................... 13

4.5 Average detection mode ....................................................................................... 14

5 EMC measurement apparatus ........................................................................................ 14

5.1 Measuring receiver ............................................................................................... 14

5.1.1 General ..................................................................................................... 14

5.1.2 The envelope detector............................................................................... 15

5.1.3 The peak detector ..................................................................................... 15

5.1.4 The quasi-peak detector ............................................................................ 15

5.2 EMC analyser ....................................................................................................... 16

5.3 Response of the measuring receiver (or EMC analyser) to disturbing signals ........ 17

5.3.1 Sinusoidal signals ..................................................................................... 17

5.3.2 Analogue television signals ....................................................................... 18

5.3.3 Impulse disturbance signals ...................................................................... 18

5.3.4 Random impulse noise signals .................................................................. 21

5.4 Response of a spectrum analyser to disturbing signals ......................................... 23

5.5 Correction factors for bandwidth and detectors ..................................................... 23

6 Measurement of analogue TV modulated signals ........................................................... 23

6.1 General considerations ......................................................................................... 23

6.2 Correction factors for bandwidth and detectors ..................................................... 24

7 Measurement of QAM modulated signals ....................................................................... 24

7.1 Peak to average ratio ............................................................................................ 24

7.2 Correction factors for bandwidth and detectors ..................................................... 25

7.3 Correction factors between different detectors ...................................................... 26

7.4 Fraction of the time the mean power is exceeded .................................................. 27

7.5 Linear operation of amplifiers ................................................................................ 27

7.6 Measurements on cable modems .......................................................................... 27

7.7 Measuring equipment setting for QAM signal level measurement .......................... 28

Annex A (informative) Field strength measurement ............................................................... 29

A.1 General .......................................................................................................................... 29

A.2 Connection of the equipment .......................................................................................... 29

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A.3 Measurement procedure ................................................................................................. 29

A.3.1 Analogue modulated signals .................................................................................. 29

A.3.2 Digitally modulated signals .................................................................................... 30

A.4 Field strength due to a transmitted power ....................................................................... 31

A.5 Received voltage due to a radiated field ......................................................................... 32

Annex B (informative) LISN (Line Impedance Stabilisation Network) ..................................... 34

Bibliography .......................................................................................................................... 35

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Foreword

This document (CLC/TR 50083-2-1:2014) has been prepared by CLC/TC 209 "Cable networks for televi-

sion signals, sound signals and interactive services".

Attention is drawn to the possibility that some of the elements of this document may be the subject of pa-

tent rights. CENELEC [and/or CEN] shall not be held responsible for identifying any or all such patent

rights.
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1 Scope
1.1 General

Standards and deliverables of EN 60728 series deal with cable networks including equipment and

associated methods of measurement for headend reception, processing and distribution of television and

sound signals and for processing, interfacing and transmitting all kinds of data signals for interactive

services using all applicable transmission media. These signals are typically transmitted in networks by

frequency-multiplexing techniques.
This includes for instance
• regional and local broadband cable networks,
• extended satellite and terrestrial television distribution systems,
• individual satellite and terrestrial television receiving systems,

and all kinds of equipment, systems and installations used in such cable networks, distribution and

receiving systems.

The extent of this standardization work is from the antennas and/or special signal source inputs to the

headend or other interface points to the network up to the terminal input of the customer premises

equipment.

The standardization work will consider coexistence with users of the RF spectrum in wired and wireless

transmission systems.

The standardization of any user terminals (i.e. tuners, receivers, decoders, multimedia terminals etc.) as

well as of any coaxial, balanced and optical cables and accessories thereof is excluded.

1.2 Specific scope of CLC/TR 50083-2-1

This Technical Report describes EMC measurements using specific measuring apparatus or alternative

methods of measurement (e.g. spectrum analyser) and applies to the radiation characteristics of EM-

active equipment (active and passive equipment) for the reception, processing and distribution of

television, sound and interactive multimedia signals as dealt with in the following parts of EN 50083 or EN

60728 series:
− EN 60728-3 "Active wideband equipment for coaxial cable networks";
− EN 60728-4 "Passive wideband equipment for coaxial cable networks";
− EN 60728-5 "Headend equipment";
− EN 60728-6 "Optical equipment";
and covers the following frequency ranges:
− 150 kHz to 30 MHz;
− 30 MHz to 1 GHz.
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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 60050-161, International Electrotechnical Vocabulary (IEV) – Chapter 161: Electromagnetic compati-

bility

EN 55016-1-1, Specification for radio disturbance and immunity measuring apparatus and methods – Part

1-1: Radio disturbance and immunity measuring apparatus – Measuring apparatus (CISPR 16-1-1)

ISO/IEC Guide 99:2007, International vocabulary of metrology - Basic and general concepts and associ-

ated terms (VIM)
3 Term, definitions, symbols and abbreviations
3.1 Terms and definitions

For the purpose of this document, the following terms and definitions apply. Also see IEC 60050-161 and

the ISO/IEC Guide 99:2007.
3.1.1
bandwidth

the width of the overall selectivity curve of the receiver between two points at a stated attenuation below

the midband response. The bandwidth is represented by the symbol B , where n is the stated attenuation

in decibels
3.1.2
CATV network

originally defined as Community Antenna Television network; now covering regional and local broadband

cable networks designed to provide sound and television signals as well as signals for interactive services

to a regional or local area
3.1.3
CISPR indicating range

it is the range specified by the manufacturer which gives the maximum and the minimum meter indica-

tions within which the receiver meets the requirements of this section of CISPR 16

3.1.4
electrical charge time constant

the time needed after the instantaneous application of a constant sine-wave voltage to the stage immedi-

ately preceding the input of the detector for the output voltage of the detector to reach 63 % of its final

value

Note 1 to entry: This time constant is determined as follows: A sine-wave signal of constant amplitude and having a

frequency equal to the mid-band frequency of the IF amplifier is applied to the input of the stage immediately preced-

ing the detector. The indication, D, of an instrument having no inertia (e.g., a cathode-ray oscilloscope) connected to

a terminal in the DC amplifier circuit so as not to affect the behaviour of the detector, is noted. The level of the signal

is chosen such that the response of the stages concerned remains within the linear operating range. A sine wave

signal of this level, applied for a limited time only and having a wave train of rectangular envelope is gated such that

the deflection registered is 0,63 D. The duration of this signal is equal to the charge time of the detector.

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3.1.5
electrical discharge time constant

the time needed after the instantaneous removal of a constant sine-wave voltage applied to the stage

immediately preceding the input of the detector for the output of the detector to fall to 37 % of its initial

value

Note 1 to entry: The method of measurement is analogous to that for the charge time constant, but instead of a signal

being applied for a limited time, the signal is interrupted for a definite time. The time taken for the deflection to fall to

0,37 D is the discharge time constant of the detector.
3.1.6
electromagnetic-active equipment

all passive and active equipment carrying RF signals are considered as electromagnetic-active equipment

because they are liable to cause electromagnetic disturbances or the performance of them is liable to be

affected by such disturbances
3.1.7
extended satellite television distribution network or system

distribution network or system designed to provide sound and television signals received by satellite re-

ceiving antenna to households in one or more buildings

Note 1 to entry: This kind of network or system could be eventually combined with terrestrial antennas for the addi-

tional reception of TV and/or radio signals via terrestrial networks.

Note 2 to entry: This kind of network or system could also carry control signals for satellite switched systems or other

signals for special transmission systems (e.g. MoCA or WiFi) in the return path direction.

3.1.8
extended terrestrial television distribution network or system

distribution network or system designed to provide sound and television signals received by terrestrial re-

ceiving antenna to households in one or more buildings

Note 1 to entry: This kind of network or system could be eventually combined with a satellite antenna for the addi-

tional reception of TV and/or radio signals via satellite networks.

Note 2 to entry: This kind of network or system could also carry other signals for special transmission systems (e.g.

MoCA or WiFi) in the return path direction.
3.1.9
impulse bandwidth
imp
B A t / 2G× IS
() ( )
imp o
max
where

A(t) is the peak of the envelope at the IF output of the receiver with an impulse area IS applied at the

max
receiver input;
G is the gain of the circuit at the centre frequency.
Specifically for two critically-coupled tuned transformers,
B 1,05 ×=BB 1,31 ×
imp 6 3
where
B and B are respectively the bandwidths at the –6 dB and –3 dB points.
6 3
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3.1.10
impulse area

the impulse area (sometimes called impulse strength, IS) is the voltage-time area of a pulse defined by

the integral:
(expressed in μVs or dB(μVs))
IS = V(t) dt

Note 1 to entry: Spectral density (δ) is related to impulse area and expressed in μV/MHz or dB(μV/MHz). For rectan-

gular impulses of pulse duration T at frequencies f << 1/T, the relationship δ (μV/MHz) = 2 10 IS (μVs) applies.

3.1.11
individual satellite television receiving system

system designed to provide sound and television signals received from satellite(s) to an individual house-

hold

Note 1 to entry: This kind of system could also carry control signals for satellite switched systems or other signals for

special transmission systems (e.g. MoCA or WiFi) in the return path direction.
3.1.12
individual terrestrial television receiving system

system designed to provide sound and television signals received via terrestrial broadcast networks to an

individual household

Note 1 to entry: This kind of system could also carry other signals for special transmission systems (e.g. MoCA or

WiFi) in the return path direction.
3.1.13
local broadband cable network

network designed to provide sound and television signals as well as signals for interactive services to a

local area (e.g. one town or one village)
3.1.14
MATV network

originally defined as Master Antenna Television network; now covering extended terrestrial television dis-

tribution networks or systems designed to provide sound and television signals received by terrestrial re-

ceiving antenna to households in one or more buildings

Note 1 to entry: This kind of network or system could be eventually combined with a satellite antenna for the addi-

tional reception of TV and/or radio signals via satellite networks.

Note 2 to entry: This kind of network or system could also carry other signals for special transmission systems (e.g.

MoCA or WiFi) in the return path direction.
3.1.15
mechanical time constant of a critically damped indicating instrument
TT= / 2π
where:
is the period of free oscillation of the instrument with all damping removed.

Note 1 to entry: For a critically damped instrument, the equation of motion of the system may be written as:

22 2
T dαα/ dt + 2T d / dt + α = ki
( )
( )
where:
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α is the deflection;
i is the current through the instrument;
k is a constant.

It can be deduced from this relationship that the time constant is also equal to the duration of a rectangular pulse (of

constant amplitude) that produces a deflection equal to 35 % of the steady deflection produced by a continuous cur-

rent having the same amplitude as that of the rectangular pulse.

Note 2 to entry: The methods of measurement and adjustment are deduced from one of the following:

a) The period of free oscillation having been adjusted to 2πT , damping is added so that αT = 0,35α .

M max

b) When the period of oscillation cannot be measured, the damping is adjusted to be just below critical such that the

over swing is not greater than 5 % and the moment of inertia of the movement is such that αT = 0,35α .

max
3.1.16
overload factor

the ratio of the level that corresponds to the range of practical linear function of a circuit (or a group of cir-

cuits) to the level that corresponds to full-scale deflection of the indicating instrument. The maximum level

at which the steady-state response of a circuit (or group of circuits) does not depart by more than 1 dB

from ideal linearity defines the range of practical linear function of the circuit (or group of circuits)

3.1.17
regional broadband cable network

network designed to provide sound and television signals as well as signals for interactive services to a

regional area covering several towns and/or villages
3.1.18
SMATV network

originally defined as Satellite Master Antenna Television network; now covering extended distribution

networks or systems designed to provide sound and television signals received by satellite receiving an-

tenna to households in one or more buildings

Note 1 to entry: This kind of network or system could be eventually combined with terrestrial antennas for the addi-

tional reception of TV and/or radio signals via terrestrial networks.

Note 2 to entry: This kind of network or system could also carry control signals for satellite switched systems or other

signals for special transmission systems (e.g. MoCA or WiFi) in the return path direction

3.1.19
symmetric voltage

in a two-wire circuit, such as a single-phase mains supply, the symmetric voltage is the radiofrequency

disturbance voltage appearing between the two wires. This is sometimes called the differential mode volt-

age. If V is the vector voltage between one of the mains terminals and earth and V is the vector voltage

a b

between the other mains terminal and earth, the symmetric voltage is the vector difference (V -V )

a b
3.1.20
weighting (of e.g. impulsive disturbance)

the pulse-repetition-frequency (PRF) dependent conversion (mainly a reduction) of a peak detected im-

pulse voltage level to an indication that corresponds to the interference effect on radio reception:

– for an analogue receiver, the psychophysical annoyance of the interference is a subjective quantity (au-

dible or visual);

– for a digital receiver, the interference effect is an objective quantity that may be defined by the critical bit

error ratio (BER) (or bit error probability (BEP)) for which perfect error correction can still occur or by

another, objective and reproducible parameter
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3.1.21
weighting characteristic

the peak voltage level as a function of PRF for a constant effect on a specific radio communication sys-

tem, i.e., the disturbance is weighted by the radio communication system itself
3.1.22
weighting function or weighting curve

the relationship between input peak voltage level and PRF for constant level indication of a measuring re-

ceiver with a weighting detector, i.e. the curve of response of a measuring receiver to repeated pulses

3.1.23
weighting factor

the value in dB of the weighting function relative to a reference PRF or relative to the peak value

3.1.24
weighting detector
detector which provides an agreed weighting function
3.1.25
weighted disturbance measurement
measurement of disturbance using a weighting detector
3.2 Symbols
Graphical Symbol Reference number Graphical Symbol Reference number
and Title and Title
Receiving antenna Amplifier
[S01239]
IEC 60617 (SO1248) Band-pass filter (BPF)
[S01249]
Low pass filter
level meter Display unit
IEC 60617 (SO1226) Sweep signal generator
Sinusoidal signal gene-
rator
Detector Mixer
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3.3 Abbreviations
AM amplitude modulation
BER bit error ratio
CATV Community Antenna Television (network)
DC direct current
DOCSIS Data Over Cable Service Interface Specification
EMC electromagnetic compatibility
EMI electromagnetic interference
EuroDOCSIS European Data Over Cable Service Interface Specification
EUT equipment under test
FM frequency modulation
IF intermediate frequency
LISN line impedance stabilisation network
LO local oscillator
LPF low lass filter
MoCA Multimedia over Cable Alliance
OTA over the air
RBW resolution bandwidth
PRF pulse repetition frequency
RF radio frequency
TDMA time division multiple access
TV television
VBW video bandwidth
WiFi Synonym of WLAN
4 Considerations on EMC measurements
4.1 General

EMC measurements below 1 GHz are specified using measuring receivers, defined in EN 55016-1-1, of

bandwidth 9 kHz or 120 kHz and quasi-peak or average detectors. However, the non-availability of such

equipment outside of the laboratory means that alternative methods of measurement (e.g. spectrum

analyser) are often used for assessment of EMC problems. This document provides guidance on the

properties of alternative detectors and the correction factors which are applied to provide equivalent

values to those obtained with the quasi-peak detector.

It is emphasised that these alternative detectors, with correction factors, are used only for indicative,

qualitative, measurements and are not a substitute for the specified quasi-peak method.

The quasi-peak detector is intended to provide a measured value that reflects the sensitivity of human ear

or eye to the pulse repetition frequencies of the impulsive noise, e.g. due to spark engine or electrical

motors, when running at low repetition frequencies, ranging from frequencies lower than 1 Hz up to 10

kHz; beyond a repetition frequency of 10 kHz there is no reduction with respect to the peak detector.

Analogue AM modulation is still used in aeronautical radio communications, in some police

communication systems, in the 2 m band and in many broadcasting and communication systems. As

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digitization of aeronautical communications, HF radio amateur, HF broadcast and VHF mobile is still an

ongoing process, the quasi-peak detector is and will remain relevant for assessing radiation effects from

CATV systems into narrow band radio systems.

In the case of broadband interference (no single carrier interference) the radiation level is measured with

a receiver having a quasi-peak detector and measuring bandwidths (according to CISPR 16-1). For single

carrier measurements other receivers can also be used.
4.2 General EMC measurement considerations

EMC measurements require the use of measuring apparatus (e.g. measuring receivers or spectrum

analysers) provided with suitable detectors of the disturbance signals produced by the equipment under

test (EUT) in order to obtain a value that is related to the annoying effect produced.

The disturbance signals can be radiated emissions or conducted emissions.

A measuring receiver able to measure the disturbance signals has the structure indicated in Figure 1.

Figure 1 – Radiated and conducted emissions measurement using a measuring receiver

A spectrum analyser able to measure the disturbance signals has the structure indicated in Figure 2.

Figure 2 – Radiated and conducted emissions measurement using a spectrum analyser

The radiated emission signals from the EUT can be applied to the measuring apparatus using a suitable

receiving antenna with a known antenna coefficient (see Annex A). The conducted emission signals from

the mains cable of the EUT are applied to the measuring apparatus by means of an appropriate coupling

unit (LISN) (see Annex B).

In the measuring apparatus, the signal to be measured is applied to the RF amplifier, mixed with the LO

signal and converted into an IF signal where a band-pass filter limits its spectrum. Then the amplitude of

the IF signal is detected, filtered and measured by an indicating meter (measuring receiver) or sent to a

display unit (CRT or LCD display) where the level is indicated and evaluated.

A spectrum analyser with specific detectors for EMC measurements is called EMC analyser.

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When only a generic spectrum analyser, with envelope (peak or average) detector, is available, the

assessment of the effect of spurious emissions from the EUT requires the knowledge of appropriate

correction factors to convert the measurements into specific IF bandwidth filtering and quasi-peak

detecting.

The following description of the behaviour of the various types of detectors associated with IF and post-

detection filtering, allows an understanding of the application of such correction factors.

4.3 Envelope (peak) detection mode

Initial EMC measurements are usually made using the envelope detector that allows determination of the

peak of the signal. This mode is much faster than quasi-peak, or average modes of detection. Signals are

normally displayed on spectrum analysers or EMC analysers in peak mode.

NOTE Since signals measured in peak detection mode always have amplitude values equal to or higher than quasi-

peak or average detection modes, it is a very easy process to take a sweep and compare the results to a limit line. If

all signals fall below the limit, then the product passes and no further testing is needed.

The envelope detector has a time constant such that the output voltage follows the peak value of the IF

signal at all times. This means that the detector can follow the fastest possible changes in the envelope of

the IF signal, but not the instantaneous value of the IF frequency waveform, as shown in Figure 3.

Figure 3 – Example of the output signal from an envelope detector with two carriers within the IF

filter bandwidth
4.4 Quasi-peak detection mode
Most rad
...

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