ETSI TR 101 830-2 V1.2.1 (2008-07)
Transmission and Multiplexing (TM); Access networks; Spectral management on metallic access networks; Part 2: Technical methods for performance evaluations
Transmission and Multiplexing (TM); Access networks; Spectral management on metallic access networks; Part 2: Technical methods for performance evaluations
RTR/ATTM-06004-2
General Information
Standards Content (Sample)
Technical Report
Transmission and Multiplexing (TM);
Access networks;
Spectral management on metallic access networks;
Part 2: Technical methods for performance evaluations
2 ETSI TR 101 830-2 V1.2.1 (2008-07)
Reference
RTR/ATTM-06004-2
Keywords
access, ADSL, HDSL, ISDN, VDSL, xDSL, local
loop, modem, network, POTS, SDSL, spectral
management, transmission, unbundling
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ETSI
3 ETSI TR 101 830-2 V1.2.1 (2008-07)
Contents
Intellectual Property Rights.5
Foreword.5
1 Scope.6
2 References.6
2.1 Normative references.7
2.2 Informative references.7
3 Definitions and abbreviations.8
3.1 Definitions.8
3.2 Abbreviations.10
4 Transmitter signal models for xDSL.11
4.1 Generic transmitter signal model.11
4.2 Transmitter signal model for "ISDN.2B1Q" .12
4.3 Transmitter signal model for "ISDN.2B1Q/filtered".13
4.4 Line-shared signal model for "ISDN.2B1Q".14
4.5 Transmitter signal model for "ISDN.MMS43" .15
4.6 Transmitter signal model for "ISDN.MMS43/filtered".15
4.7 Line-shared signal model for "ISDN.MMS43" .16
4.8 Transmitter signal model for "HDSL.2B1Q" .17
4.9 Transmitter signal model for "HDSL.CAP".18
4.10 Transmitter signal model for "SDSL" .19
4.11 Transmitter signal model for "ADSL/POTS (FO)" .20
4.12 Transmitter signal model for "ADSL/POTS (FDD)" .20
4.13 Transmitter signal model for "ADSL/ISDN (FO)".22
4.14 Transmitter signal model for "ADSL/ISDN (FDD)".23
4.15 Transmitter signal model for "ADSL2/J (FDD)" .24
4.16 Transmitter signal model for "ADSL2/M (FDD)" .25
4.17 Transmitter signal model for "VDSL1".26
4.17.1 Templates compliant with the ETSI main band plan.28
4.17.2 Templates compliant with the ETSI optional band plan.31
4.18 Transmitter signal models for "VDSL2" .34
4.18.1 Noise floor.35
4.18.2 Building block #1 for "PSD Band Constructor" .35
4.18.3 Building block #2 for "PSD Shaper" .37
4.18.4 Building block #3 for "PSD notcher" .37
4.18.5 Building block #4 for "PSD Power Restrictor".38
4.18.6 Pre-defined downstream tables for "PSD Band Constructor".39
4.18.7 Pre-defined upstream tables for "PSD Band Constructor".43
4.18.8 Example definitions of VDSL2 transmitters.46
5 Generic receiver performance models for xDSL.47
5.1 Generic input models for effective SNR .49
5.1.1 First order input model .49
5.2 Generic detection models.51
5.2.1 Generic Shifted Shannon detection model.51
5.2.2 Generic PAM detection model.52
5.2.3 Generic CAP/QAM detection model .53
5.2.4 Generic DMT detection model .54
5.3 Generic models for echo coupling.57
5.3.1 Linear echo coupling model.57
6 Specific receiver performance models for xDSL .58
6.1 Receiver performance model for "HDSL.2B1Q".58
6.2 Receiver performance model for "HDSL.CAP".59
6.3 Receiver performance model for "SDSL" .59
6.4 Receiver performance model for "ADSL/POTS (FO)".60
ETSI
4 ETSI TR 101 830-2 V1.2.1 (2008-07)
6.5 Receiver performance model for "ADSL/POTS (FDD)" .61
6.6 Receiver performance model for "ADSL/ISDN (FO)" .63
6.7 Receiver performance model for "ADSL/ISDN (FDD)" .64
6.8 Receiver performance model for "VDSL" .65
7 Transmission and reflection models.66
7.1 Summary of test loop models.66
8 Crosstalk models.66
8.1 Basic models for crosstalk cumulation.66
8.1.1 Uniform cumulation model.67
8.1.2 FSAN sum for crosstalk cumulation.68
8.2 Basic models for NEXT and FEXT coupling.68
8.2.1 Normalized NEXT and FEXT coupling at an elementary cable section.69
8.2.2 Normalized NEXT and FEXT coupling at distributed or branched cables.69
8.3 Basic models for crosstalk injection.71
8.3.1 Forced noise injection.71
8.3.2 Current noise injection.72
8.4 Overview of different network topologies.72
8.5 Crosstalk evaluation for multi-node topologies.73
8.6 Crosstalk evaluation for two-node topologies .74
9 Examples of evaluating various scenarios.77
9.1 European Spectral Platform 2004 (ESP/2004) .77
9.1.1 Technology mixtures within ESP/2004 .77
9.1.2 System models within ESP/2004.78
9.1.3 Topology models within ESP/2004 .79
9.1.4 Loop models within ESP/2004 .82
9.1.5 Scenarios within ESP/2004.83
Annex A: Bibliography.84
History .85
ETSI
5 ETSI TR 101 830-2 V1.2.1 (2008-07)
Intellectual Property Rights
IPRs essential or potentially essential to the present document may have been declared to ETSI. The information
pertaining to these essential IPRs, if any, is publicly available for ETSI members and non-members, and can be found
in ETSI SR 000 314: "Intellectual Property Rights (IPRs); Essential, or potentially Essential, IPRs notified to ETSI in
respect of ETSI standards", which is available from the ETSI Secretariat. Latest updates are available on the ETSI Web
server (http://webapp.etsi.org/IPR/home.asp).
Pursuant to the ETSI IPR Policy, no investigation, including IPR searches, has been carried out by ETSI. No guarantee
can be given as to the existence of other IPRs not referenced in ETSI SR 000 314 (or the updates on the ETSI Web
server) which are, or may be, or may become, essential to the present document.
Foreword
This Technical Report (TR) has been produced by ETSI Technical Committee Access, Terminals, Transmission and
Multiplexing (ATTM).
The present document is part 2 of a multi-part deliverable covering Transmission and Multiplexing (TM); Access
networks; Spectral management on metallic access networks, as identified below:
Part 1: "Definitions and signal library";
Part 2: "Technical methods for performance evaluations";
ETSI
6 ETSI TR 101 830-2 V1.2.1 (2008-07)
1 Scope
The present document gives guidance on a common methodology for studying the impact of noise on xDSL
performance (maximum reach, noise margin, maximum bitrate) when changing parameters within various Spectral
Management scenarios. These methods enable reproducible results and a consistent presentation of the assumed
conditions (characteristics of cables and xDSL equipment) and configuration (chosen technology mixture and cable fill)
of each scenario.
The technical methods include computer models for estimating:
• xDSL receiver capability of detecting signals under noisy conditions;
• xDSL transmitter characteristics;
• cable characteristics;
• crosstalk cumulation in cables, originating from a mix of xDSL disturbers.
The objective is to provide the technical means for evaluating the performance of xDSL equipment within a chosen
scenario. This includes the description of performance properties of equipment.
Another objective is to assist the reader with applying this methodology by providing examples on how to specify the
configuration and the conditions of a scenario in an unambiguous way. The distinction is that a configuration of a
scenario can be controlled by access rules while the conditions of a scenario cannot.
Possible applications of the present document include:
• Studying access rules, for the purpose of bounding the crosstalk in unbundled networks.
• Studying deployment rules, for the various systems present in the access network.
• Studying the impact of crosstalk on various technologies within different scenarios.
The scope of the present document is explicitly restricted to the methodology for defining scenarios and quantifying the
performance of equipment within such a scenario. All judgement on what access rules are required, what performance is
acceptable, or what combinations are spectral compatible, is explicitly beyond the scope of the present document. The
same applies for how realistic the example scenarios are.
The models in the present document are not intended to set requirements for DSL equipment. These requirements are
contained in the relevant transceiver specifications. The models in the present document are intended to provide a
reasonable estimate of real-world performance but may not include every aspect of modem behaviour in real networks.
Therefore real-world performance may not accurately match performance numbers calculated with these models.
2 References
References are either specific (identified by date of publication and/or edition number or version number) or
non-specific.
• For a specific reference, subsequent revisions do not apply.
• Non-specific reference may be made only to a complete document or a part thereof and only in the following
cases:
- if it is accepted that it will be possible to use all future changes of the referenced document for the
purposes of the referring document;
- for informative references.
Referenced documents which are not found to be publicly available in the expected location might be found at
http://docbox.etsi.org/Reference.
ETSI
7 ETSI TR 101 830-2 V1.2.1 (2008-07)
For online referenced documents, information sufficient to identify and locate the source shall be provided. Preferably,
the primary source of the referenced document should be cited, in order to ensure traceability. Furthermore, the
reference should, as far as possible, remain valid for the expected life of the document. The reference shall include the
method of access to the referenced document and the full network address, with the same punctuation and use of upper
case and lower case letters.
NOTE: While any hyperlinks included in this clause were valid at the time of publication ETSI cannot guarantee
their long term validity.
2.1 Normative references
The following referenced documents are indispensable for the application of the present document. For dated
references, only the edition cited applies. For non-specific references, the latest edition of the referenced document
(including any amendments) applies.
Not applicable.
2.2 Informative references
The following referenced documents are not essential to the use of the present document but they assist the user with
regard to a particular subject area. For non-specific references, the latest version of the referenced document (including
any amendments) applies.
SpM
[i.1] ETSI TR 101 830-1: "Transmission and Multiplexing (TM); Access networks; Spectral
management on metallic access networks; Part 1: Definitions and signal library".
[i.2] ANSI T1E1.4, T1.417-2003: "Spectrum Management for loop transmission systems".
ISDN
[i.3] ETSI TS 102 080: "Transmission and Multiplexing (TM); Integrated Services Digital Network
(ISDN) basic rate access; Digital transmission system on metallic local lines".
HDSL
[i.4] ETSI TS 101 135: "Transmission and Multiplexing (TM); High bit-rate Digital Subscriber Line
(HDSL) transmission systems on metallic local lines; HDSL core specification and applications
for combined ISDN-BA and 2 048 kbit/s transmission".
SDSL
[i.5] ETSI TS 101 524: "Transmission and Multiplexing (TM); Access transmission system on metallic
access cables; Symmetric single pair high bitrate Digital Subscriber Line (SDSL)".
[i.6] ITU-T Recommendation G.991.2: "Single-Pair High-Speed Digital Subscriber Line (SHDSL)
transceivers".
ADSL
[i.7] ETSI TS 101 388: "Transmission and Multiplexing (TM); Access transmission systems on
metallic access cables; Asymmetric Digital Subscriber Line (ADSL) - European specific
requirements [ITU-T Recommendation G.992.1 modified]".
[i.8] ITU-T Recommendation G.992.1: "Asymmetric digital subscriber line (ADSL) transceivers".
[i.9] ITU-T Recommendation G.992.3: "Asymmetric digital subscriber line (ADSL) transceivers - 2
(ADSL2)".
ETSI
8 ETSI TR 101 830-2 V1.2.1 (2008-07)
[i.10] ITU-T Recommendation G.992.5: "Asymmetric digital subscriber line (ADSL) transceivers -
extended bandwidth ADSL2 (ADSL2plus)".
VDSL
[i.11] ETSI TS 101 270-1: "Transmission and Multiplexing (TM); Access transmission systems on
metallic access cables; Very high speed Digital Subscriber Line (VDSL); Part 1: Functional
requirements".
[i.12] ETSI TS 101 271: "Access Terminals Transmission and Multiplexing (ATTM); Access
transmission systems on metallic pairs; Very high speed Digital Subscriber Line system
(VDSL2)". [ITU-T Recommendation G993.2, modified].
[i.13] ITU-T Recommendation G993.2: "Very High Speed Digital Subscriber Line 2 (VDSL2)".
SPLITTERS
[i.14] ETSI TS 101 952-1-3: "Access network xDSL transmission filters; Part 1: ADSL splitters for
European deployment; Sub-part 3: Specification of ADSL/ISDN splitters".
[i.15] ETSI TS 101 952-1-4: "Access network xDSL transmission filters; Part 1: ADSL splitters for
European deployment; Sub-part 4: Specification of ADSL over "ISDN or POTS" universal
splitters".
OTHER
[i.16] ITU-T Recommendation G997.1: "Physical layer management for digital subscriber line (DSL)
receivers".
3 Definitions and abbreviations
3.1 Definitions
For the purposes of the present document, the following terms and definitions apply:
access port: physical location, appointed by the loop provider, where signals (for transmission purposes) are injected
into the local loop wiring
access rule: mandatory rule for achieving access to the local loop wiring, equal for all network operators who are
making use of the same network cable that bounds the crosstalk in that network cable
cable fill (or degree of penetration): number and mixture of transmission techniques connected to the ports of a binder
or cable bundle that are injecting signals into the access ports
Cable Management Plan (CMP): list of selected access rules dedicated to a specific network
NOTE: This list may include associated descriptions and explanations.
deployment rule: voluntary rule, irrelevant for achieving access to the local loop wiring and proprietary to each
individual network operator
NOTE: A deployment rule reflects a network operator's own view about what the maximum length or maximum
bitrate may be for offering a specific transmission service to ensure a chosen minimum quality of service.
disturber: source of interference in spectral management studies coupled to the wire pair connecting victim modems
NOTE: This term is intended solely as a technical term, defined within the context of these studies, and is not
intended to imply any negative judgement.
ETSI
9 ETSI TR 101 830-2 V1.2.1 (2008-07)
downstream transmission: transmission direction from port, labelled as LT-port, to a port, labelled as NT-port
NOTE: This direction is usually from the central office side via the local loop wiring, to the customer premises.
Echo Cancelled (EC): term used within the context of ADSL to designate ADSL (FO) systems with frequency overlap
of downstream and upstream signals
NOTE: In this context, the usage of the abbreviation "EC" was only kept for historical reasons. The usage of the
echo cancelling technology is not only limited to FO systems (frequency overlapped), but can also be
used by FDD systems (frequency division duplexing).
local loop wiring: part of a metallic access network, terminated by well-defined ports, for transporting signals over a
distance of interest
NOTE: This part includes mainly cables, but may also include a Main Distribution Frame (MDF), street cabinets,
and other distribution elements. The local loop wiring is usually passive only, but may include active
splitter-filters as well.
loop provider: organization facilitating access to the local loop wiring
NOTE: In several cases the loop provider is historically connected to the incumbent network operator, but other
companies may serve as loop provider as well.
LT-access port (or LT-port for short): access port for injecting signals, designated as "LT-port"
NOTE: Such a port is commonly located at the central office side, and intended for injecting "downstream"
signals.
max data rate: maximum data rate that can be recovered according to predefined quality criteria, when the received
noise is increased with a chosen noise margin (or the received signal is decreased with a chosen signal margin)
network operator: organization that makes use of a local loop wiring for transporting telecommunication services
NOTE: This definition covers incumbent as well as competitive network operators.
noise margin: ratio (P /P ) by which the received noise power P may increase to power P until the recovered
n2 n1 n1 n2
signal no longer meets the predefined quality criteria
NOTE: This ratio is commonly expressed in dB.
NT-access port (or NT-port for short): is an access port for injecting signals, designated as "NT-port"
NOTE: Such a port is commonly located at the customer premises, and intended for injecting "upstream" signals.
performance: is a measure of how well a transmission system fulfils defined criteria under specified conditions
NOTE: Such criteria include reach, bitrate and noise margin.
power back-off: is a generic mechanism to reduce the transmitter's output power
NOTE: It has many purposes, including the reduction of power consumption, receiver dynamic range, crosstalk,
etc.
power cut-back: specific variant of power back-off, used to reduce the dynamic range of the receiver, that is
characterized by a frequency independent reduction of the in-band PSD
NOTE: It is used, for instance, in ADSL and SDSL.
PSD mask: absolute upper bound of a PSD, measured within a specified resolution band
NOTE: The purpose of PSD masks is usually to specify maximum PSD levels for stationary signals.
PSD template: expected average PSD of a stationary signal
NOTE: The purpose of PSD templates is usually to perform simulations. The levels are usually below or equal to
the associated PSD masks.
ETSI
10 ETSI TR 101 830-2 V1.2.1 (2008-07)
signal category: is a class of signals meeting the minimum set of specifications identified in TR 101 830-1 [i.1]
NOTE: Some signal categories may distinct between different sub-classes, and may label them for instance as
signals for "downstream" or for "upstream" purposes.
signal margin: ratio (P /P ) by which the received signal power P may decrease to power P until the recovered
s1 s2 s1 s2
signal no longer meets the predefined quality criteria
NOTE: This ratio is commonly expressed in dB.
spectral compatibility: generic term for the capability of transmission systems to operate in the same cable
NOTE: The precise definition is application dependent and has to be defined for each group of applications.
spectral management: art of making optimal use of limited capacity in (metallic) access networks
NOTE: This is for the purpose of achieving the highest reliable transmission performance and includes:
Designing of deployment rules and their application.
Designing of effective access rules.
Optimized allocation of resources in the access network, e.g. access ports, diversity of systems
between cable bundles, etc.
Forecasting of noise levels for fine-tuning the deployment.
Spectral policing to enforce compliance with access rules.
Making a balance between conservative and aggressive deployment (low or high failure risk).
spectral management rule: generic term, incorporating (voluntary) deployment rules, (mandatory) access rules and all
other (voluntary) measures to maximize the use of local loop wiring for transmission purposes
transmission equipment: equipment connected to the local loop wiring that uses a transmission technique to transport
information
transmission system: set of transmission equipment that enables information to be transmitted over some distance
between two or more points
transmission technique: electrical technique used for the transportation of information over electrical wiring
upstream transmission: transmission direction from a port, labelled as NT-port, to a port, labelled as LT-port
NOTE: This direction is usually from the customer premises, via the local loop wiring, to the central office side.
victim modem: modem, subjected to interference (such as crosstalk from all other modems connected to other wire
pairs in the same cable) that is being studied in a spectral management analysis
NOTE: This term is intended solely as a technical term, defined within the context of these studies, and is not
intended to imply any negative judgement.
3.2 Abbreviations
For the purposes of the present document, the following abbreviations apply:
2B1Q 2-Binary, 1-Quaternary (Use of 4-level PAM to carry two buts per pulse)
ADSL Asymmetric Digital Subscriber Line
BER Bit Error Ratio
CAP Carrier less Amplitude/Phase modulation
CMP Cable Management Plan
DFE Decision Feedback Equalizer
DMT Discrete MultiTone modulation
EC Echo Cancelled
EPL Estimated Power Loss
ETSI
11 ETSI TR 101 830-2 V1.2.1 (2008-07)
FBL Fractional Bit Loading
FDD Frequency Division Duplexing/Duplexed
FO Frequency Overlap, previously referred to as Echo Cancelled (EC)
FSAN Full Service Access Network
GABL Gain Adjusted Bit Loading
HDSL High bitrate Digital Subscriber Line
ISDN Integrated Services Digital Network
LT-port Line Termination - port (commonly at central office side)
LTU Line Termination Unit
MDF Main Distribution Frame
NT-port Network Termination - port (commonly at customer side)
NTU Network Termination Unit
PAM Pulse Amplitude Modulation
PBO Power Back-Off
PSD Power Spectral Density (single sided)
QAM Quadrature Amplitude Modulation
RBL Rounded Bit Loading
SDSL Symmetrical (single pair high bitrate) Digital Subscriber Line
SNR Signal to Noise Ratio (ratio of powers)
TBL Truncated Bit Loading
TRA TRAnsmitter
UC Ungerboeck Coded (also known as trellis coded)
VDSL Very-high-speed Digital Subscriber Line
xDSL (all systems) Digital Subscriber Line
4 Transmitter signal models for xDSL
A transmitter model in this clause is mainly a PSD description of the transmitted signal under matched conditions, plus
an output impedance description to cover mismatched conditions as well.
PSD masks of transmitted xDSL signals are specified in several documents for various purposes, for instance in
TR 101 830-1 [i.1]. These PSD masks, however, cannot be applied directly to the description of a transmitter model.
One reason is that masks are specifying an upper limit, and not the expected (averaged) values. Another reason is that
the definition of the true PSD of a time-limited signal requires no resolution bandwidth at all (it is defined by means of
an autocorrelation, followed by a Fourier transform) while PSD masks do rely on some resolution bandwidth. They
describe values that are (slightly) different from the true PSD; especially at steep edges (e.g. guard bands), and for
modelling purposes this difference is sometimes very relevant.
To differentiate between several PSD descriptions, masks and templates of a PSD are given a different meaning. Masks
are intended for proving compliance to standard requirements, while templates are intended for modelling purposes.
This clause summarizes various xDSL transmitter models, by defining template spectra of output signals.
In some cases, models are marked as "default" and/or as "alternative". Both models are applicable, but in case a
preference of either of them does not exist, the use of the "default" models is recommended. Other (alternative) models
may apply as well, provided that they are specified.
4.1 Generic transmitter signal model
A generic model of an xDSL transmitter is essentially a linear signal source. The Thevenin equivalent of such a source
equals an ideal voltage source U having a real resistor R in series. The output voltage of this source is random in
s s
nature (as a function of the time), and occupies a relatively broad spectrum. Correlation between transmitters is taken to
be negligible. The autocorrelation properties of a transmitter's signal are taken to be adequately represented by a PSD
template.
ETSI
12 ETSI TR 101 830-2 V1.2.1 (2008-07)
This generic model can be made specific by defining:
• The output impedance R of the transmitter.
s
• The template of the PSD, measured at the output port, when terminated with an external impedance equal to
R . This is identified as the "matched condition", and under this condition the output power equals the
s
maximum power that is available from this source. Under all other (mis-matched) termination conditions the
output power will be lower.
4.2 Transmitter signal model for "ISDN.2B1Q"
The PSD template for modelling the "ISDN.2B1Q" transmit spectrum is defined by the theoretical sinc-shape of PAM
encoded signals, with additional filtering and with a noise floor. The PSD is the maximum of both power density
curves, as summarized in expression 1 and the associated table 1. The coefficient q scales the total signal power of
N
P (f) to a value that equals P . This value is dedicated to the used filter characteristics, but equals q =1 when no
1 ISDN N
filtering is applied (f →0, f →∞). The source impedance equals 135 Ω.
L H
2× q ⎛ f ⎞ 1 1
N
⎜ ⎟
P ( f ) = P × × sinc × × [W / Hz]
1 ISDN
⎜ ⎟ 2⋅N 2
H
f f
X ⎝ X ⎠ f f
⎛ ⎞ ⎛ ⎞
L
1+ 1+
⎜ ⎟ ⎜ ⎟
f f
⎝ H ⎠ ⎝ ⎠
(P /10)
floor _ dBm
P ( f ) = [W / Hz]
P( f ) = max()P ( f ), P ( f ) [W / Hz]
1 2
Where:
P /10
ISDN _ dBm
P = (10 ) 1000 [W]
ISDN
R = 135 [Ω]
S
sinc(x) = sin(π·x) / (π·x)
Default values for remaining parameters are summarized in table 1.
Expression 1: PSD template for modelling "ISDN.2B1Q" signals
Different ISDN implementations, may use different filter characteristics, and noise floor values. Table 1 specifies
nd
default values for ISDN implementations, in the case where 2 order Butterworth filtering has been applied. The
default noise floor equals the maximum PSD level that meets the out-of-band specification of the ISDN standard
(TS 102 080 [i.3]).
Table 1: Default parameter values for the ISDN.2B1Q templates, as defined in expression 1
Type fX fH fL NH qN PISDN_dBm Pfloor_dBm
[kHz] [kHz] [kHz] [dBm] [dBm/Hz]
ISDN.2B1Q 80 1×f 0 2 1,1257 13,5 -120
x
nd
NOTE: These default values are based on 2 order Butterworth filtering.
ETSI
13 ETSI TR 101 830-2 V1.2.1 (2008-07)
4.3 Transmitter signal model for "ISDN.2B1Q/filtered"
When ISDN signals have to pass a low-pass filter (such as in an ADSL splitter) before they reach the line, the
disturbance caused by these ISDN systems to other wire pairs will change, as well as their performance. SpM studies
should therefore make a distinction between crosstalk generated from ISDN systems connected directly to the line and
filtered ISDN systems.
The PSD template for modelling a "ISDN.2B1Q/filtered" transmitter signal that has passed a low-pass splitter/filter, is
defined in table 2 in terms of break frequencies. It has been constructed from the transmitter PSD template, filtered by
the low-pass transfer function representing the splitter/filter.
The values are based on filter assumptions according to splitter specifications in TS 101 952-1-3 [i.14] and
TS 101 952-1-4 [i.15]. The associated values are constructed with straight lines between these break frequencies, when
plotted against a logarithmic frequency scale and a linear dBm scale.
Table 2: PSD template for modelling "ISDN.2B1Q/filtered" signals
ISDN.2B1Q/filtered
(135Ω)
f [Hz] PSD
[dBm/Hz]
1 k -32,1
10 k -32,3
20 k -33,1
30 k -34,5
40 k -36,6
50 k -39,8
60 k -44,5
65 k -47,8
70 k -52,2
75 k -59,3
80 k -126,5
85 k -61,9
90 k -57,4
100 k -55,2
110 k -57,9
115 k -62,9
120 k -68,2
125 k -79,3
130 k -90,8
135 k -104,1
140 k -117,9
145 k -132,8
150 k -136,9
160 k -140,0
170 k -140,0
180 k -136,2
190 k -135,2
200 k -135,8
210 k -137,8
220 k -140,0
30 M -140,0
ETSI
14 ETSI TR 101 830-2 V1.2.1 (2008-07)
4.4 Line-shared signal model for "ISDN.2B1Q"
The PSD template for modelling the line-shared signal from an ISDN.2B1Q transmitter that has passed the low-pass
and the high-pass part of a splitter/filter for sharing the line with ADSL signals, is defined in table 3 in terms of break
frequencies. It has been constructed from the transmitter PSD template, filtered by the low-pass and the high-pass
transfer function representing the splitter/filter.
The values are based on filter assumptions according to splitter specifications in TS 101 952-1-3 [i.14] and in
TS 101 952-1-4 [i.15]. The associated values are constructed with straight lines between these break frequencies, when
plotted against a logarithmic frequency scale and a linear dBm scale.
Table 3: PSD template for modelling line shared "ISDN.2B1Q" signals
Line-shared ISDN.2B1Q
(135Ω)
f [Hz] PSD [dBm/Hz]
1 k -40,1
10 k -40,3
20 k -41,0
30 k -42,2
40 k -44,1
50 k -46,8
60 k -51,1
65 k -54,2
70 k -58,3
75 k -65,1
80 k -127,0
85 k -66,9
90 k -61,9
100 k -59,0
110 k -61,2
115 k -65,9
120 k -70,9
125 k -81,7
130 k -93,0
135 k -106,1
140 k -119,4
145 k -134,1
150 k -138,0
160 k -140,0
170 k -140,0
180 k -137,2
190 k -136,2
200 k -136,8
210 k -138,8
220 k -140,0
30 M -140,0
ETSI
15 ETSI TR 101 830-2 V1.2.1 (2008-07)
4.5 Transmitter signal model for "ISDN.MMS43"
The PSD template for modelling the "ISDN.MMS43" transmit spectrum (also known as ISDN.4B3T) is defined by a
combination of a theoretical curve and a noise floor. The PSD is the maximum of both power density curves, as
summarized in expression 2. The source impedance equals 150 Ω.
⎡ ⎤
⎛ ⎞ ⎛ ⎞ ⎛ ⎞
2 f f − f f − f 1 1
2 2 P1 2 P2
⎜ ⎟ ⎜ ⎟ ⎜ ⎟
P ( f ) = P × × sinc + sinc + sinc × × [W / Hz]
⎢ ⎥
1 ISDN
⎜ ⎟ ⎜ ⎟ ⎜ ⎟
4 4
f f f f
⎢ ⎥
0 ⎝ 0 ⎠ ⎝ 0 ⎠ ⎝ 0 ⎠ ⎛ f ⎞ ⎛ f ⎞
⎣ ⎦
1+ 1+
⎜ ⎟ ⎜ ⎟
f f
⎝ L1 ⎠ ⎝ L2 ⎠
P( f ) = P ( f ) + P [W / Hz]
1 floor
Where:
P /10
ISDN _ dBm
P = (10 ) 1000 [W], P = 13,5 dBm
ISDN ISDN_dBm
P /10
floor _ dBm
( )
P = 10 1000 [W/Hz], P = -125 dBm/Hz
floor
floor_dBm
f = 120 kHz; f = 1 020 kHz; f = 1 860 kHz; f = 80 kHz; f = 1 020 kHz;
0 P1 P2 L1 L2
sinc(x) = sin(π·x) / (π·x)
Expression 2: PSD template for modelling "ISDN.MMS43" signals
4.6 Transmitter signal model for "ISDN.MMS43/filtered"
When ISDN signals have to pass a low-pass filter (such as in an ADSL splitter) before they reach the line, the
disturbance caused by these ISDN systems to other wire pairs will change, as well as their performance. SpM studies
should therefore make a distinction between crosstalk generated from ISDN systems connected directly to the line and
filtered ISDN systems.
The PSD template for modelling a "ISDN.MMS43/filtered" transmitter signal that has passed a low-pass splitter/filter,
is defined in table 4 in terms of break frequencies. It has been constructed from the transmitter PSD template, filtered by
the low-pass transfer function representing the splitter/filter.
The values are based on filter assumptions according to splitter specifications in TS 101 952-1-3 [i.14] and in
TS 101 952-1-4 [i.15]. The associated values are constructed with straight lines between these break frequencies, when
plotted against a logarithmic frequency scale and a linear dBm scale.
ETSI
16 ETSI TR 101 830-2 V1.2.1 (2008-07)
Table 4: PSD template for modelling "ISDN.MMS.43/filtered" signals
ISDN.MMS.43/filtered
(150 Ω)
f [Hz] PSD
[dBm/Hz]
1 k -34,5
10 k -34,6
20 k -35,0
30 k -35,7
40 k -36,7
50 k -38,2
60 k -40,2
70 k -42,8
80 k -46,2
90 k -50,8
100 k -56,8
110 k -66,8
115 k -80,3
120 k -93,6
125 k -106,9
130 k -112,4
135 k -122,5
140 k -131,4
150 k -130,4
170 k -129,8
190 k -132,7
200 k -134,8
210 k -137,6
216 k -140,0
30 M -140,0
4.7 Line-shared signal model for "ISDN.MMS43"
The PSD template for modelling the line-shared signal from an ISDN.MMS43 transmitter (also known as vv
ISDN.4B3T), that has passed the low-pass and the high-pass part of a splitter/filter for sharing the line with ADSL
signals, is defined in table 5 in terms of break frequencies. It has been constructed from the transmitter PSD template,
filtered by the low-pass and the high-pass transfer function representing the splitter/filter.
The values are based on filter assumptions according to splitter specifications in TS 101 952-1-3 [i.14] and in
TS 101 952-1-4 [i.15]. The associated values are constructed with straight lines between these break frequencies, when
plotted against a logarithmic frequency scale and a linear dBm scale.
ETSI
17 ETSI TR 101 830-2 V1.2.1 (2008-07)
Table 5: PSD template for modelling line shared "ISDN.MMS.43" signals
Line-shared ISDN.MMS.43
(150 Ω)
f [Hz] PSD [dBm/Hz]
1 k -42,5
10 k -42,6
20 k -42,9
30 k -43,4
40 k -44,2
50 k -45,3
60 k -46,8
70 k -48,9
80 k -51,7
90 k -55,3
100 k -60,6
110 k -70,1
115 k -83,0
120 k -96,0
125 k -109,1
130 k -114,3
135 k -124,0
140 k -132,7
150 k -131,5
170 k -130,8
190 k -133,7
200 k -135,8
210 k -138,6
216 k -140,0
30 M -140,0
4.8 Transmitter signal model for "HDSL.2B1Q"
The PSD templates for modelling the spectra of various "HDSL.2B1Q" transmitters are defined by the theoretical
sinc-shape of PAM encoded signals, with additional filtering and a noise floor. The PSD template is the maximum of
both power density curves, as summarized in expression 3 and associated table 6.
The coefficient q scales the total signal power of P (f) to a value that equals P . This value is dedicated to the filter
N 1 0
characteristics used, but equals q =1 when no filtering is applied (f →0, f →∞). The source impedance equals 135 Ω.
N L H
⎛ ⎞
2× q f 1 1 1
N 2
P ( f ) = P × ×sinc ⎜ ⎟× × × [W / Hz]
1 HDSL
2 2⋅N 2⋅N
⎜ ⎟
H1 H 2
f f
f
X ⎝ X ⎠ ⎛ ⎞ ⎛ f ⎞ ⎛ f ⎞
L
1+ 1+ 1+
⎜ ⎟ ⎜ ⎟ ⎜ ⎟
f f f
⎝ ⎠ ⎝ H1 ⎠ ⎝ H 2 ⎠
(P /10)
floor _ dBm
P ( f ) = [W / Hz]
[W / Hz]
P( f ) = max()P ( f ), P ( f )
1 2
Where:
P /10
HDSL _ dBm
P = (10 ) 1000 [W]
HDSL
R = 135 [Ω ]
S
sinc(x) = sin(π·x) / (π·x)
Default values for remaining parameters are summarized in table 6.
Expression 3: PSD template for modelling "HDSL.2B1Q" signals
ETSI
18 ETSI TR 101 830-2 V1.2.1 (2008-07)
Different HDSL implementations, may use different filter characteristics, and noise floor values. Table 6 summarizes
default values for modellin
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