IEC 60728-13:2010

IEC 60728-13 ®
Edition 1.0 2010-01
INTERNATIONAL
STANDARD
colour
inside
Cable networks for television signals, sound signals and interactive services –
Part 13: Optical systems for broadcast signal transmissions

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IEC 60728-13 ®
Edition 1.0 2010-01
INTERNATIONAL
STANDARD
colour
inside
Cable networks for television signals, sound signals and interactive services –
Part 13: Optical systems for broadcast signal transmissions

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
PRICE CODE
XB
ICS 33.160.01; 33.180.01 ISBN 978-2-88910-264-8
– 2 – 60728-13 © IEC:2010(E)
CONTENTS
FOREWORD.5
INTRODUCTION.7
1 Scope.8
2 Normative references .8
3 Terms, definitions, symbols and abbreviations.9
3.1 Terms and definitions .9
3.2 Symbols .15
3.3 Abbreviations .16
4 Optical system reference model.17
5 Preparation of measurement .19
5.1 Environmental conditions .19
5.1.1 Standard measurement conditions.19
5.1.2 Temperature and humidity .20
5.1.3 Setting up the measuring setup and system under test .20
5.1.4 AGC operation.20
5.1.5 Impedance matching between pieces of equipment .20
5.1.6 Standard operating condition .20
5.1.7 Standard signal and measuring equipment .20
5.2 Accuracy of measuring equipment.21
5.3 Source power .21
6 Methods of measurement .21
6.1 Measuring points and items.21
6.1.1 General .21
6.1.2 Measuring points .21
6.1.3 Measured parameters.21
6.2 Optical power .22
6.2.1 General .22
6.2.2 Measuring setup .22
6.2.3 Measuring method .23
6.2.4 Precaution for measurement.23
6.2.5 Presentation of the results.24
6.3 Carrier level and carrier-to-noise ratio .24
6.3.1 General .24
6.3.2 Measuring setup .24
6.3.3 Measuring conditions.24
6.3.4 Measuring method for analogue signals (AM-VSB) .24
6.3.5 Measuring method for digitally modulated signals (64 QAM, OFDM) .25
6.3.6 Precautions for measurement .25
6.3.7 Presentation of the results.25
6.4 Carrier-to-noise ratio defined by optical signal.25
6.4.1 General .25
6.4.2 Measuring setup .26
6.4.3 Measuring conditions.27
6.4.4 System RIN measuring method.27
6.4.5 C/N calculation based on RIN value.29
6.4.6 Component RIN calculation .29

60728-13 © IEC:2010(E) – 3 –
6.5 Optical modulation index .31
6.6 Carrier-to-crosstalk ratio (CCR) .31
6.6.1 General .31
6.6.2 Equipment .31
6.6.3 General measurements .32
6.6.4 Procedure.32
6.6.5 Potential sources of error .33
6.6.6 Presentation of the results.33
7 Specification of optical system for broadcast signal transmission .33
7.1 Analogue and digital broadcast system over optical network .33
7.2 International TV systems .34
7.3 Relationship between RIN and C/N.35
7.4 Optical wavelength .36
7.5 Frequency of source signal .36
7.6 Optical system specification for broadcast signal transmission .36
7.7 C/N ratio specification for in-house and in-building wirings .37
7.8 Crosstalk due to optical fibre non-linearity.39
7.9 Single frequency interference level due to fibre non-linearity.40
7.10 Environmental conditions .40
Annex A (informative) Actual service systems and design considerations .41
Annex B (informative) Optical system overview.56
Annex C (informative) Optical system degradations .60
Annex D (normative) Measurement of parameters (R, I , I and G) required for RIN
d0 eq
calculation .66
Bibliography.68

Figure 1 – Optical system reference model for one-fibre solution .18
Figure 2 – Optical system reference model for two-fibres solution.18
Figure 3 – Example of PON triplexer.19
Figure 4 – Performance specified points of the optical system .19
Figure 5 – Typical optical video distribution system.21
Figure 6 – Measurement of optical power using a WDM coupler .23
Figure 7 – Measurement of optical power using a wavelength filter .23
Figure 8 – Arrangement of test equipment for carrier-to-noise ratio measurement.24
Figure 9 – Measuring points in the optical cable TV network .26
Figure 10 – RIN measurement setup.27
Figure 11 – Arrangement of test equipment for measuring other services crosstalk.32
Figure 12 – Performance allocation and measuring points .33
Figure 13 – Section of C/N ratio specification (45 dB) for in-house wiring (specified for
electrical signals).38
Figure 14 – Section of C/N ratio specification for in-house wiring (specified for optical
signals).39
Figure A.1 – Example of a multi-channel service system of one million terminals .41
Figure A.2 – Example of a multi-channel service system of 2 000 terminals .42
Figure A.3 – Example of re-transmission service system of 72 terminals.43
Figure A.4 – Example of re-transmission service system of 144 terminals.43

– 4 – 60728-13 © IEC:2010(E)
Figure A.5 – Model No.1 of a system performance calculation .47
Figure A.6 – Model No.2 of a system performance calculation .48
Figure A.7 – Model No.3 a of system performance calculation .49
Figure A.8 – Model No.4 of a system performance calculation .50
Figure A.9 – Model No.5 of a system performance calculation .51
Figure A.10 – Model No.6 of a system performance calculation .52
Figure A.11 – Model No.7 of system performance calculation .53
Figure B.1 – Topology of optical system .56
Figure B.2 – Network composition.57
Figure B.3 – Example of SS system .58
Figure B.4 – Example of ADS system.58
Figure B.5 – Example of PON system .59
Figure C.1 – Reflection model.60
Figure C.2 – Degradation factors of optical transmission system.61
Figure C.3 – SBS generation image .61
Figure C.4 – Interference between two wavelengths .63
Figure C.5 – Simulation of SRS(OLT transmission power versus D/U) .63
Figure C.6 – Simulation of SRS (D/U in arbitrary unit versus fibre length) .64
Figure C.7 – Fibre length of the first peak of SRS D/U versus frequency.64
Figure C.8 – GE-PON idle pattern spectrum (IEEE 802.3ah 1000Base-PX) (62,5 MHz =
1 250 Mbps/20 bit) .65
Figure D.1 – Measurement of gain (G) .67

Table 1 – Level of RF signals.12
Table 2 – Measuring instruments .20
Table 3 – Measuring points and measured parameters .22
Table 4 – Parameters used for the calculation of carrier-to-noise ratio (C/N).30
Table 5 – Minimum C/N requirements in operation.34
Table 6 – Minimum RF signal-to-noise ratio requirements in operation.34
Table 7 – Types of broadcast services .36
Table 8 – Type of service and minimum operational RIN values.36
Table 9 – Optical system specification .37
Table 10 – Section of C/N ratio specification for in-house/in-building wiring .38
Table 11 – Interference level due to fibre non-linearity.40
Table 12 – Environmental conditions .40
Table A.1 – Operating conditions of a multi-channel service system .42
Table A.2 – Operating conditions of re-transmission service system .43
Table A.3 – Basic system parameters for multi-channel and re-transmission service
systems .45
Table A.4 – Verified optimum operation .54
Table B.1 – PON systems and main parameters .59
Table C.1 – Disturbance parameter of Raman crosstalk.62

60728-13 © IEC:2010(E) – 5 –
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
CABLE NETWORKS FOR TELEVISION SIGNALS,
SOUND SIGNALS AND INTERACTIVE SERVICES –

Part 13: Optical systems for broadcast signal transmissions

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
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2) The formal decisions or agreements of IEC on technical matters express, as nearly as possible, an international
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5) IEC itself does not provide any attestation of conformity. Independent certification bodies provide conformity
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6) All users should ensure that they have the latest edition of this publication.
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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 60728-13 has been prepared by technical area 5: Cable networks
for television signals, sound signals and interactive services, of IEC technical committee 100:
Audio, video and multimedia systems and equipment.
The text of this standard is based on the following documents:
FDIS Report on voting
100/1623/FDIS 100/1646/RVD
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.

– 6 – 60728-13 © IEC:2010(E)
The list of all the parts of the IEC 60728 series, under the general title Cable networks for
television signals, sound signals and interactive services, can be found on the IEC website.
The committee has decided that the contents of this publication will remain unchanged until
the maintenance result date indicated on the IEC web site 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.
A bilingual version of this publication may be issued at a later date.
The contents of the corrigendum of August 2010 have been included in this copy.
IMPORTANT – The 'colour inside' logo on the cover page of this publication indicates
that it contains colours which are considered to be useful for the correct
understanding of its contents. Users should therefore print this document using a
colour printer.
60728-13 © IEC:2010(E) – 7 –
INTRODUCTION
Standards of the IEC 60728 series deal with cable networks including equipment and
associated methods of measurement for headend reception, processing and distribution of
television signals, sound signals and their associated data signals and for processing,
interfacing and transmitting all kinds of signals for interactive services using all applicable
transmission media.
This includes
• CATV0-networks;
• MATV-networks and SMATV-networks;
• individual receiving networks;
and all kinds of equipment, systems and installations installed in such networks.
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.
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.
—————————
This word encompasses the HFC (Hybrid Fibre Cable) networks used nowadays to provide telecommunications

services, voice, data, audio and video both broadcast and narrowcast.

– 8 – 60728-13 © IEC:2010(E)
CABLE NETWORKS FOR TELEVISION SIGNALS,
SOUND SIGNALS AND INTERACTIVE SERVICES –

Part 13: Optical systems for broadcast signal transmissions

1 Scope
This part of IEC 60728 is applicable to optical transmission system for broadcast signal
transmission that consists of a head-end equipment, optical transmission lines, in-house
wirings and a system outlet. The system is primarily intended for television and sound signals
using analogue and/or digital transmission technology. This standard specifies the basic
system parameters and methods of measurement for optical distribution system having a
system outlet in order to assess the system performance and its performance limits.
The purpose of this part of IEC 60728 is to describe the system specification of FTTH (fibre to
the home) network for broadcast signal transmission. This standard is also applicable to the
broadcast signal transmission using telecommunication network if it satisfies the optical
portion of this standard. This standard describes RF transmission for broadcast and
narrowcast (limited area distribution of broadcast) signals over FTTH, and introduces xPON
system as a physical layer media. The detailed description of physical layer is out of the
scope of this standard. The scope is limited to RF signal transmission over FTTH, thus, it
does not include IP transport technologies, such as IP Multicast and associate protocols.
Some interference descriptions between telecommunication system and broadcast system
addressed in Clause 7 and Annex D should be referred to for detailed explanations. Annex A
describes actual service systems with design consideration based on this standard. Annex B
gives an overview of the optical transmission systems applicable for broadcast signal
transmission.
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.
IEC 60068-1:1988, Environmental testing – Part 1: General and guidance
IEC 60728-1:2007, Cable networks for television signals, sound signals and interactive
services – Part 1: System performance of forward paths
IEC 60728-6:2003, Cable networks for television signals, sound signals and interactive
services – Part 6: Optical equipment
IEC/TR 60728-6-1:2006, Cable networks for television signals, sound signals and interactive
services – Part 6-1: System guidelines for analogue optical transmission systems
IEC 60825-1, Safety of laser products – Part 1: Equipment classification and requirements
IEC 60825-2, Safety of laser products – Part 2: Safety of optical fibre communication
systems (OFCS)
IEC 60825-12, Safety of laser products – Part 12: Safety of free space optical
communication systems used for transmission of information

60728-13 © IEC:2010(E) – 9 –
IEC 61291-1:2006, Optical amplifiers – Part 1: Generic specification
IEC 61755-1:2005, Fibre optic connector optical interfaces – Part 1: Optical interfaces for
single mode non-dispersion shifted fibres – General and guidance
IEC 61930:1998, Fibre optic graphical symbology
IEC 61931:1998, Fibre optic – Terminology
ITU-T Recommendation G.692, Optical interfaces for multichannel systems with optical
amplifiers
ITU-T Recommendation G.694.2, 0H0HSpectral grids for WDM applications: CWDM wavelength
grid
3 Terms, definitions, symbols and abbreviations
3.1 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
3.1.1
optical transmitting unit
optical transmitter
transmit fibre optic terminal device accepting at its input port an electrical signal and providing
at its output port an optical carrier modulated by that input signal
[IEC 61931, definition 2.9.6]
NOTE 1 For the purposes of this document, optical transmitters may have more than one input port accepting
electrical RF signals.
NOTE 2 This piece of equipment amplifies frequency multiplexed electrical signals and converts these electrical
signals into optical signals. The optical wavelength is a 1 500 nm band (1 550 ± 10 nm in 1 530 nm to 1 625 nm
region).
3.1.2
optical receiving unit
optical receiver
receive fibre optic terminal device accepting at its input port a modulated optical carrier, and
providing at its output port the corresponding demodulated electrical signal (with the
associated clock, if digital)
[IEC 61931, definition 2.9.7]
NOTE For the purposes of this document, optical receivers may have more than one output port providing
electrical RF signals.
3.1.3
optical amplifier
optical waveguide device containing a suitably pumped, active medium which is able to
amplify an optical signal
[IEC 61931, definition 2.7.75]
NOTE 1 In this document, Erbium Doped Fibre Amplifier (EDFA) is used for amplification in the 1 550 nm band.
NOTE 2 There are several methods based on wavelength to be used for amplification. The term “Erbium Doped
Fibre Amplifier (EDFA)” is the synonym of optical amplifier in this document.

– 10 – 60728-13 © IEC:2010(E)
3.1.4
fibre optic branching device
optical fibre coupler
splitter
optical fibre device, possessing three or more optical ports, which shares optical power
among its ports in a predetermined fashion, at the same wavelength or wavelengths, without
wavelength conversion
NOTE The ports may be connected to fibres, detectors, etc.
[IEC 61931, definition 2.6.21, modified]
3.1.5
multiplexing device
WDM device
wavelength selective branching device (used in WDM transmission systems) in which optical
signals can be transferred between two predetermined ports, depending on the wavelength of
the signal
[IEC 61931, definition 2.6.51]
3.1.6
optical modulation index
th
optical modulation index of k RF carrier,m is defined as
k
φφ−
hl
m =
k
φφ+
hl
total optical modulation index, M is defined as
K
M = m
∑
k
k =1
where
φ is the highest and
h
φ is the lowest instantaneous optical power of the intensity modulated optical signal,
l
K is the total number of RF carriers and
M is the total optical modulation index.
NOTE This term is mainly used for analogue systems.
[IEC 60728-6, definition 3.1.10, modified]
3.1.7
noise figure
decrease of the signal-to-noise ratio (SNR), at the output of an optical detector with unitary
quantum efficiency and zero excess noise, due to the propagation of a shot noise-limited
signal through the optical fibre amplifier, expressed in dB
[IEC 61291-1, definition 3.2.38]
NOTE The noise figure of optical amplifiers depends on the optical input power and on the wavelength used.

60728-13 © IEC:2010(E) – 11 –
3.1.8
relative intensity noise
RIN
ratio of the mean square of the intensity fluctuations in the optical power of a light source to
the square of the mean of the optical output power
−1
NOTE 1 The RIN is usually expressed in dB(Hz ) resulting in negative values.
[IEC 60728-6, definition 3.1.12, modified]
NOTE 2 The value of RIN can also be calculated from the results of a carrier-to-noise measurement for the
system.
3.1.9
responsivity
ratio of an optical detector’s electrical output to its optical input at a given wavelength
NOTE 1 The responsivity is generally expressed in Ampere per Watt or Volt per Watt of incident radiant power.
NOTE 2 Sensitivity is sometimes used as an imprecise synonym for responsivity.
NOTE 3 The wavelength interval around the given wavelength may be specified.
[IEC 60728-6, definition 3.1.15]
3.1.10
wavelength
distance covered in a period by the wavefront of a harmonic plane wave
NOTE The wavelength of light in vacuum is given by
λ
c
λ =
f
where
c
is the speed of light in vacuum c = 2,997 92 × 10 m/s);
f is the optical frequency
Although the wavelength in dielectric material, such as fibres, is shorter than in vacuum, only the wavelength of
light in vacuum is used.
[IEC 60728-6, definition 3.1.17, modified]
3.1.11
central wavelength
the average of those wavelengths at which the amplitude of a light source reaches or last falls
to half of the maximum amplitude
[IEC 60728-6, definition 3.1.26]
3.1.12
AM-VSB signal
sideband in which only the spectral components corresponding to the lower frequencies of the
modulating signals are preserved, the other components being strongly attenuated
[IEV 702-06-28, modified]
NOTE This is the abbreviation for the vestigial sideband amplitude modulated signal used in the terrestrial
broadcasting and CATV transmission system.

– 12 – 60728-13 © IEC:2010(E)
3.1.13
QAM signal
quadrature amplitude modulation
QAM
amplitude modulation by two separate signals of two sinusoidal carriers having the same
amplitude and frequency but being in phase quadrature, the modulated signals being added
for transmission in a single channel
[IEV 702-06-63, modified]
3.1.14
OFDM signal
orthogonal frequency division multiplexing is one of the multiplexing schemes used for the
transportation of terrestrial digital broadcasting SDTV and HDTV signals
NOTE OFDM is based on the idea of frequency-division multiplexing, where each frequency channel is modulated
with a simpler modulation, and the frequencies and modulation of FDM are arranged to be orthogonal with each
other, which almost eliminates the interference between channels.
3.1.15
RF signal level definition
level of an RF signal is defined in 128H128HTable 1; it is expressed in microvolt or in dB(μV) or
in dB(mW)
3.1.16
AM-VSB analogue signals
vision carrier signal level is the RMS value of the vision carrier at the peak of the modulation
envelope (C ), expressed in dB(μV) and measured across a 75 Ω termination or referred to
rms
75 Ω
NOTE This will correspond, in negative modulation systems, to the carrier amplitude during synchronizing pulses
and, in positive modulation systems, to that at peak white level without a chrominance signal, as shown in ITU-R
Recommendation BT.470, Figure 1.
3.1.17
FM radio or FM audio carrier of a TV signals
level of an FM radio or of an FM audio carrier of a TV signal is the RMS value of the carrier
expressed in dB(μV) and measured across a 75 Ω termination or referred to 75 Ω
3.1.18
digitally modulated signals
level of a digitally modulated signal is given by the RMS power of the signal within the
channel bandwidth (S ) and can be expressed in dB(mW) or in dB(μV) referred to 75 Ω
D,RF
NOTE The level of an OFDM signal is the average electrical power of the overall signal comprised of multi-
carriers and is not the individual carrier level of the multi-carrier signal, as shown in Table 1.
Table 1 – Level of RF signals
Remarks
Signal Level detection Symbol
AM-VSB RMS value of the carrier at the peak of the
peak value C
rms
video carrier modulation envelope.
Analogue
TV signal
FM audio
RMS value C The carrier level is a constant value.
rms
carrier
QAM signal RMS value
The value is averaged over a sufficiently long
S period of time compared to period of the lowest
D,RF
frequency used for the modulation.
OFDM signal RMS value
60728-13 © IEC:2010(E) – 13 –
3.1.19
carrier-to-noise ratio
C/N
signal-to-noise ratio
S /N
D,RF
ratios are given by
C/N (dB) = C – N (for analogue signals)
rms rms
S /N (dB) = S – N (for digital signals)
D,RF D,RF rms
where N is the RMS level of the noise in the equivalent noise bandwidth of the RF channel,
rms
expressed in dB(mW) or in dB(μV) referred to 75 Ω
NOTE The level of the analogue modulated carrier or of the RF digitally modulated signal and the level of the
noise shall be expressed in the same units, in dB(mW) or in dB(μV) measured across a 75 Ω termination or
referred to 75 Ω.
3.1.20
D/U ratio
ratio of desired signal level, D[dB(μV)], to undesired signal level, U[dB(μV)]
NOTE The D/U ratio is generally used for multiple frequency interference as CSO and CTB, for single frequency
interference as CCR.
3.1.21
single or multiple frequency interference
besides the C/N and S /N ratios, single or multiple frequency interference to video signal is
D.RF
defined as the ratio of desired signal level and undesired signal level
NOTE 1 The ratio of desired signal level, D(dB(μV)), to undesired signal level, U(dB(μV)) is given by
D/U (dB) = D − U
NOTE 2 The desired and the undesired signals can also be expressed both in dB(mW).
3.1.22
optical line terminal
OLT
central office-terminal equipment that is linked with the Optical Network Unit (ONU) in
customer premises
NOTE OLT usually connects with headend equipment.
3.1.23
optical network unit
ONU
terminal equipment linked with OLT
3.1.24
video-optical network unit
V-ONU
terminal unit that changes the optical signal of a broadcast system into an electric signal
NOTE The term V-ONU is used as the synonym of optical receiver (O/E) in this standard.

– 14 – 60728-13 © IEC:2010(E)
3.1.25
stimulated Brillouin scattering
SBS
non-linear scattering of optical radiation characterized by a frequency shift as for the Raman
scattering, but accompanied by a lower frequency (acoustical) vibration of the medium lattice;
the light is scattered backward with respect to the incident radiation
[IEC 61931, definition 2.1.88]
NOTE 1 In silica fibres the frequency shift is typically around 10 GHz.
NOTE 2 SBS results in loss of optical level and affects the performance of analogue optical system.
NOTE 3 The frequency shift is characterized by a frequency downshift (that is to a longer wavelength) due to
a GHz frequency acoustical vibration (frequency downshift is 10 or 11 GHz, and gain bandwidth 20 MHz).
3.1.26
self-phase modulation
SPM
increase of the refractive index of optical fibres due to excessive optical power launched into
the fibre
NOTE 1 Modulated optical signal induces modulation of refractive index, which means that the phase of optical
signal varies in time. The nonlinear phase modulation is caused by a device or a system itself, therefore it is called
self-phase modulation.
NOTE 2 SPM affect the distortion properties of an analogue optical transmission.
3.1.27
stimulated Raman scattering
SRS
non-linear scattering of optical radiation characterized by a wavelength shift and accompanied
by very high frequency vibration of the medium lattice, strongly enhanced by the presence of
already scattered radiation
[IEC 61931, definition 2.1.87]
NOTE 1 In silica fibres the wavelength shift is typically around 100 nm for an exciting radiation with a wavelength
around 1 550 nm.
NOTE 2 Stimulated Raman scattering can occur in both forward and backward directions and can cause crosstalk
between optical signals of different wavelengths.
NOTE 3 Frequency downshift is about 13 THz and gain bandwidth about 20 GHz.
3.1.28
cross-phase modulation
XPM
caused by the nonlinear refractive index of the fibre material
NOTE 1 XPM has a relationship with the wavelength spacing in an optical transmission system. The more the
spacing increases, the more the XPM value decreases. In such a WDM system having 1 490 nm (communication
signal) and 1 550 nm (broadcast signal) wavelengths, XPM becomes negligibly small compared to SRS due to this
relationship.
NOTE 2 XPM affects the performance of the wavelength division multiplex system.
3.1.29
Rayleigh scattering
light scattering in a medium due to in-homogeneity in material density or composition of that
medium which are small with respect to wavelength
NOTE The scattered power is inversely proportional to the fourth power of the wavelength.

60728-13 © IEC:2010(E) – 15 –
[IEV 731-03-37] and [IEC 61931, definition 2.1.76]
3.1.30
crosstalk
carrier-to-crosstalk ratio
CCR
level difference of CATV broadcast carrier level and worst case of other services single
frequency crosstalk signal measured at RF output port of optical receiver for CATV broadcast
service
CCR =D −U
CATV OtherService
where
D is the nominal level of CATV broadcast signal in dB(µV) at RF output port of
CATV
optical CATV broadcast receiver,
U is the worst case level of another service’s single frequency crosstalk in dB(µV)
OtherService
at RF output port of optical CATV broadcast receiver. The value of U is
OtherService
mainly due to the Raman scattering effect.
CCR is expressed in dB.
3.2 Symbols
The following graphical symbols are used in the figures of this standard. These symbols are
either listed in IEC 60617 or based on symbols defined in IEC 60617.
Optical transmitter Optical amplifier
based on
[IEC 60617-S00127
[IEC 60617-S01231 and
(2001-07)]
IEC 60617-S01239
(2001-07)]
Optical fibre
Variable attenuator
[IEC 60617-S01318 [IEC 60617-S01245,
(2001-07)]
modified
(2001-07)]
Optical receiver Power meter
based on
[IEC 60617-S00059,
[IEC 60617-S00213
IEC 60617-S00910
(2001-07)] (2001-07)]
Electrical spectrum Amplifier
analyzer
[IEC 60617-S01239
based on
modified
[IEC 60617-S00059 (2001-07)]
and
IEC 60617-S00910
(2001-07)]
– 16 – 60728-13 © IEC:2010(E)
Ammeter Photodiode with fibre
based on
pigtail
[IEC 60617-S00059
[IEC 60617-S01327
and
(2001-07)]
IEC 60617-S00910
(2001-07)]
Coupler
[IEC 60617-S00059 Optical filter
Optical
and
Filter
IEC 60617-S01188
(2001-07)]
Optical terminator
[IEC 60617-S01389 NF meter
NF
and
Meter
IEC 60617-S013182F1F ]
Optical splitter
[3.33.1 of IEC 61930] Television set
TVTV
Video optical network
V-ONU unit
3.3 Abbreviations
ADS Active Double Star AGC Automatic Gain Control
AM Amplitude Modulation APC Angled Physical Contact optical
connector
BCH Bose-Chaudhuri-Hocquenghem CATV Community Antenna Television
multiple error correction binary (network)
block code
CODFM Coded Orthogonal Frequency CCR Carrier-To-Crosstalk ratio
Division Multiplex
C/N Carrier-to-Noise ratio CPE Customer Premises Equipment
CSO CTB
Composite Second Order Composite Triple Beat
CW Continuous Wave
DS Down Stream or Double Star DSF Dispersion Shifted Fibre
D/U Desired to Undesired signal ratio EDFA Erbium-Doped Fibre Amplifier
E/O Optical transmitter (Electrical-to-FM Frequency Modulation
Optical transducer)
FTTB Fibre To The Building FTTH Fibre To The Home
HDTV High Definition Television H/E Headend
HFC Hybrid Fibre Coaxial ITU-T International Telecommunication
Union – Telecommunication
sector
LD Laser Diode LDPC Low-Density Parity Check (codes)
—————————
IEC 60617-S01318 is for reference only, obsolete since 1996-05.

60728-13 © IEC:2010(E) – 17 –
MC Media Converter MDU Multiple Dwelling Unit
MER Modulation Error Ratio NF Noise Figure
O/E Optical Receiver (OpticaltTo OFCS Optical Fibre Communication
Electrical transducer) System
OFDM Orthogonal Frequency Division OLT Optical Line Terminal
Multiplex
OMI Optical Modulation Index ONU Optical Network Unit
PD Photo Diode PDS Passive Double Star
PER Packet Error Ratio PON Passive Optical Network
QAM Quadrature Amplitude Modulation QPSK Quaternary Phase Shift Keying
RIN Relative Intensity Noise RBW Resolution Bandwidth
RF Radio Frequency SBS Stimulated Brillouin Scattering
SDTV Standard Definition Television SDU Single Dwelling Unit
SMF Single Mode Fibre S/N Signal-to-Noise ratio
SPM Self-Phase Modulation
SRS Stimulated Raman Scattering SS Single Star
US Up Stream VBW Video Bandwidth
V-ONU Video Optical Network Unit AM-VSB Amplitude Modulation-Vestigial
Side Band
WDM Wavelength Division Multiplexing XPM Cross-Phase Modulation
SW Switch
4 Optical system reference model
129H129HFigure 1 and Figure 2 show the optical system reference model for broadcast signal
transmission
...