ETSI TS 101 952-2 V1.1.1 (2010-11)

Technical Specification
Access, Terminals, Transmission and Multiplexing (ATTM);
Access network xDSL splitters
for European deployment;
Part 2: Generic specification of xDSL over
ISDN splitters and xDSL universal splitters

2 ETSI TS 101 952-2 V1.1.1 (2010-11)

Reference
RTS/ATTM-06011
Keywords
ADSL, ADSL2, ADSL2plus, ISDN, POTS, splitter
VDSL, VDSL1, VDSL2
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ETSI
3 ETSI TS 101 952-2 V1.1.1 (2010-11)
Contents
Intellectual Property Rights . 6
Foreword . 6
Introduction . 7
1 Scope . 8
2 References . 8
2.1 Normative references . 8
2.2 Informative references . 9
3 Definitions, symbols and abbreviations . 10
3.1 Definitions . 10
3.2 Symbols . 11
3.3 Abbreviations . 12
4 General functional description of xDSL over ISDN splitters and universal splitters . 13
4.1 Functional diagram . 14
4.2 High pass filter . 15
5 Circuit definitions, testing conditions and methods . 15
5.1 DC and ringing testing conditions . 15
5.1.1 Polarity independence . 15
5.1.2 DC feeding voltage and current . 15
5.1.3 DC feeding and loading bridges . 16
5.1.4 Ringing signals and the DC added to the ringing . 17
5.2 AC Terminating impedances Z . 17
AC
5.2.1 Z and Z (xDSL transceiver related) . 17
RefDSL DSL-i
5.2.2 Z and Z (ISDN related) . 17
T L
5.2.3 Z (POTS and ISDN related) . 17
Line
5.2.4 Z (POTS related) . 17
R
5.2.5 Z (POTS related) . 18
RHF
5.2.6 Z (POTS related), Impedance On-hook High Impedance . 18
OnHI
5.2.7 Z (POTS related), Impedance On-hook Low Impedance . 19
OnLI
5.2.8 Z (POTS related), Impedance On-hook . 19
OnHo
5.2.9 Z (POTS related), Impedance load for ringing . 19
ring
5.3 High pass filter implementation . 19
5.3.1 DCB capacitors as reference high pass filter . 20
5.4 General transmission test set-ups . 20
5.4.1 General definition of the Insertion Loss (IL) measurement . 20
5.4.2 POTS or ISDN signal loss test set-up: IL LINE port to TELE port . 21
5.4.3 xDSL signal isolation: TELE port to xDSL port . 21
5.4.4 Insertion Loss test set-up LINE port to xDSL port . 22
5.4.5 General definition of the Return Loss . 24
5.4.6 Return Loss test set-up at LINE port and TELE port . 25
5.5 Unbalance measurement . 25
5.5.1 General definition of Longitudinal Conversion Loss . 26
5.5.2 General definition of Longitudinal Conversion Transfer Loss . 26
5.5.3 LCL and LCTL test set-up . 26
5.6 Noise measurement . 28
5.6.1 Psophometric noise in the POTS Band . 28
5.6.2 Noise in the ISDN Band . 28
5.6.3 Noise in the xDSL Band . 28
5.7 Common Mode Rejection Ratio measurement . 28
6 Splitter requirements . 29
6.1 DC requirements . 29
6.1.1 DC resistance to earth . 29
6.1.2 DC isolation resistance between A-wire and B-wire . 29
ETSI
4 ETSI TS 101 952-2 V1.1.1 (2010-11)
6.1.3 DC series resistance . 29
6.1.4 DC signalling (for universal splitter only) . 29
6.2 Ringing frequency requirements for the LPF (for universal splitter only) . 30
6.2.1 Total harmonic distortion at 25 Hz and 50 Hz . 30
6.3 POTS and ISDN band IL requirements for the LPF . 30
6.3.1 POTS pass band loss requirements (for universal splitter only) . 30
6.3.1.1 On-hook POTS pass band insertion loss and distortion . 30
6.3.1.2 Off-hook POTS pass band insertion loss . 31
6.3.1.3 Off-hook POTS pass band insertion loss distortion . 31
6.3.2 ISDN pass band insertion loss . 31
6.4 POTS and ISDN band return loss requirements for the LPF . 32
6.4.1 POTS band return loss . 32
6.4.2 Pass band return loss for ISDN . 32
6.5 Requirements relating to metering pulses at 12 kHz or 16 kHz (for universal splitter only) (optional) . 33
6.6 Unbalance about earth . 34
6.6.1 Unbalance of the low pass part . 34
6.6.2 Unbalance of the high pass part . 34
6.7 xDSL band related requirements . 35
6.7.1 xDSL band isolation: IL between TELE port and xDSL port . 36
6.7.2 xDSL signal loss: IL between LINE port and xDSL port . 36
6.8 Noise . 37
6.8.1 POTS band audible noise level requirements . 37
6.8.2 ISDN band noise level requirements . 37
6.8.3 xDSL band noise level requirements . 37
6.9 Intermodulation distortion . 37
6.9.1 POTS band intermodulation distortion requirements (mandatory) . 37
6.9.2 ISDN band intermodulation distortion requirements (F.F.S.) . 38
6.9.3 xDSL band intermodulation distortion requirements (optional) . 38
6.10 Delay distortion . 39
6.10.1 POTS band delay distortion . 39
6.10.2 ISDN band delay distortion . 39
6.11 POTS/ISDN transient effects (optional) . 39
6.11.1 POTS transient effects (optional) . 39
6.11.2 ISDN transient effects (optional) . 40
6.12 Requirements for Common Mode rejection (optional). 40
6.13 Requirements for Crosstalk at the LE (optional) . 40
Annex A (normative): xDSL specific information . 41
A.1 Z and Z for specific xDSL variants . 41
DSL-i RefDSL
A.1.1 Generic definition of Z , using C , Z , C , L . 41
DSL-i DCB RefDSL DSL DSL
A.1.2 Z for ADSL over ISDN/Universal . 42
DSL-i
A.1.3 Z for European VDSL1 over ISDN/Universal, with US0 . 43
DSL-i
A.1.4 Z and Z for VDSL2 over ISDN with US0 . 43
DSL-i DSL-i2
A.2 General requirements for ISDN and universal splitters . 43
A.3 Specific requirements for passive splitters for ADSL over ISDN variants . 46
A.4 Specific requirements for passive splitters for VDSL1 over ISDN variants . 47
A.5 Specific requirements for passive splitters for VDSL2 over ISDN variants at the TE side . 47
A.6 Specific requirements for passive splitters for VDSL2 over ISDN variants at the LE side . 48
Annex B (informative): Evolution of the documents . 49
Annex C (informative): Use of the present document for splitters at the cabinet . 50
C.1 Splitters on POTS lines at the cabinet . 50
C.2 Splitters for ISDN lines at the cabinet . 50
Annex D (informative): IL and RL caused by the Z in the POTS or ISDN band . 51
DSL-i
ETSI
5 ETSI TS 101 952-2 V1.1.1 (2010-11)
Annex E (informative): IL Measurement inside Z . 52
DSL-i
E.1 IL TELE port to xDSL port (clause 5.4.3) inside Z . 52
DSL-i
E.2 IL LINE port to xDSL port (clause 5.4.4) inside Z . 53
DSL-i
Annex F (informative): Return Loss measurements: practical diagrams. 55
Annex G (informative): Insertion Loss measured with feeding and loading bridges . 56
Annex H (informative): Dynamic tests of splitters in the presence of xDSL transceivers . 57
H.1 General description of TR-127 of the Broadband Forum. 57
H.2 Dynamic ISDN tests needed (in a revision of TR-127). 57
Annex I (informative): Optimal transmission of POTS or ISDN signals and xDSL signals
and their separation . 58
Annex J (informative): More on feeding and loading bridges . 59
Annex K (informative): Additional requirements for Active Splitter (F.F.S.) . 60
Annex L (informative): Measuring when C capacitors are merged with Z . 61
DCB DSL-i
L.1 Adapting clause 5.4.2 . 61
L.2 Adapting clause 5.4.3 . 62
L.3 Adapting clause 5.4.4 . 62
L.4 Adapting clause 5.4.6 . 64
Annex M (informative): Measuring IL of the splitter low pass in the xDSL band . 66
Annex N (informative): Bibliography . 67
History . 68

ETSI
6 ETSI TS 101 952-2 V1.1.1 (2010-11)
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 Specification (TS) 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 Access network xDSL Transmission Filters, as
identified below:
Part 1: "Generic specification of xDSL over POTS splitters";
Part 2: "Generic specification of xDSL over ISDN splitters and xDSL universal splitters";
Part 3: "Generic specification of distributed filters for xDSL over POTS";
Part 4: "Additional specification for dynamic distributed filters for xDSL over POTS" (under study).
NOTE 1: The present document is derived by merging and complementing 3 older, existing specifications, which
were numbered according to the older structure of the splitter documents. Before the publication of the 3
or 4 parts as described above, the TS 101 952 was composed of 2 parts, which discriminated between
ADSL and VDSL, with several subparts. For reasons of simplicity the TS is now restructured as a set of
only 3 (potentially 4) documents, intended for both ADSL and VDSL when applicable. The older
structure of the documents is explained in informative Annex B.
NOTE 2: Useful information on splitter tests may be found in TR 101 953-1-1 [i.3], TR 101 953-1-2 [i.4],
TR 101 953-1-3 [i.5], TR 101 953-2-1 [i.6], TR 101 953-2-2 [i.7] and TR 101 953-2-3 [i.8]. These
documents are linked to the previous versions of the splitter specifications. The TR 101 953
multi-part [i.3], [i.4], [i.5], [i.6], [i.7] and [i.8] e.g. describe the combination of the AC testing conditions
of the test set-ups with the DC conditions controlled via feeding and loading bridges. The TR 101 953
multi-part [i.3], [i.4], [i.6] and [i.7] are intended for splitter over POTS, but also applicable to universal
splitters. TR 101 953-1-3 [i.5] and TR 101 953-2-3[i.8] are intended for splitters over ISDN. If there is a
discrepancy between the present document and the older TR 101 953 series of documents, the present
document prevails.
The present document is fully in line with initiative "eEurope 2002 - An Information Society For All", under "The
contribution of European standardization to the eEurope Initiative, A rolling Action Plan" especially under the key
objective of a cheaper, faster and secure Internet.
ETSI
7 ETSI TS 101 952-2 V1.1.1 (2010-11)
Introduction
Remarks on and limitations of the present document
The present document covers all xDSL system variants, such as ADSL1, ADSL2, ADSL2plus, VDSL1 and VDSL2. It
is applicable at the Local Exchange (LE) (i.e. network) side of the line at the LE or at the cabinet and at the Terminal
Equipment (TE) (i.e. user) side of the line. A number of limitations and remarks should be listed:
1) The use of the present document is extended to splitters at the cabinet for both the POTS case (universal
splitters) and the ISDN-only case, as explained in Annex C. However, this extension has to be applied with
care in the case of ISDN. But, as explained in Annex C also, there is evidence that the splitters tested
according to the present document will perform satisfactorily when used at the cabinet.
2) The present document covering the xDSL over ISDN or the Universal splitters was gained from the experience
with passive and static xDSL splitters, the original state of the art for this application. Furthermore, the
experience was gained with identical requirements at either side of the line. Therefore, the requirements in the
present document are primarily intended for passive and static filters, with identical requirements for the LE
side and the TE side of the line. However, in the note under table A.3 an optional diversification between
splitters requirements at the two sides of the line is described. For the TE side splitters an optional variant
could be allowed with better downstream protection, with less IL in the upstream band and more IL in the
downstream band. Similar differentiation between LE and TE is possible for the balance requirements; see the
note under table A.10.
3) The present document covering xDSL over POTS splitters is limited to passive and static splitters. There are
other classes of filters possible, besides passive and static splitters. Such active and/or dynamic filters are
composed of other elements than passive components. Active/dynamic splitters require different and
additional requirements and test methods to be specified. The full specification of requirements for
active/dynamic splitters is F.F.S. (for further study).
4) For certain static properties in the present document it is possible to relax the requirements and prove in
dynamic tests that the splitter performs sufficiently well. These dynamic tests are compiled in TR-127, by the
Broadband Forum. The use of the TR-127 methodology for this purpose is outside the scope of this version of
the present document. The TR-127 could prove useful to introduce splitters with reduced complexity, or active
and/or dynamic splitters. The TR-127 methodology for POTS splitters is now published [i.16]. A tutorial text
on TR-127 is given in informative Annex H. Finalizing splitter tests in the present document based on TR-127
for ISDN signals and for ISDN and DSL interaction is F.F.S., as the version for ISDN splitters is still under
definition in the Broadband Forum.
5) To test distortion, noise and other requirements in the present document the TR-127 methodology is sometime
a superior methodology, or even the only feasible method at an acceptable complexity. Indeed, TR-127 will
prove that a splitter works correctly in a worst case xDSL test environment, including POTS and ISDN
signals. The use of the TR-127 [i.16] methodology for this purpose is introduced for certain clauses in the
present document. With such tests, based on actual xDSL transceiver results, one can avoid requirements are
either inadequate or potentially unnecessarily strong.
6) The majority of requirements in the present document are generic and applicable to all splitters for xDSL over
ISDN or universal splitters over both ISDN and POTS. In the case where any requirements are applicable to
only one particular flavour of xDSL, this is clearly indicated in the clause describing the requirement. The
relevant information about requirements for specific xDSL system variants is given in Annex A.
ETSI
8 ETSI TS 101 952-2 V1.1.1 (2010-11)
1 Scope
The present document specifies requirements and test methods for the low pass and high pass parts of xDSL over ISDN
splitters and for xDSL over "ISDN or POTS universal" splitters.
• The xDSL over ISDN splitters allow only ISDN underlying the broadband xDSL band.
• The xDSL over "ISDN or POTS universal" splitter shall support either POTS or ISDN transmission underlying
the broadband xDSL band.
These splitters are intended to be installed at the Local Exchange (LE or network) side of the local loop, either at the LE
or at a remote cabinet, and at the TE (i.e. user) side near the NTP. In the case of splitters at the TE side, the present
document specifies the "central splitter" (also called "master splitter") that is intended for use at the demarcation point
of the customer premises.
The present document covers the following xDSL variants: ADSL, ADSL2, ADSL2plus, VDSL1 and VDSL2, defined
in the relevant ITU-T documents listed in informative references and the bibliography.
The splitter filter, as specified by the present document, may be implemented as an independent unit, separately from
the xDSL transceiver, or may be integrated with the xDSL termination unit. The splitter may also be integrated with the
base band termination unit (e.g. POTS or ISDN line card). However, this is outside of the scope of the present
document.
2 References
References are either specific (identified by date of publication and/or edition number or version number) or
non-specific. For specific references, only the cited version applies. For non-specific references, the latest version of the
reference document (including any amendments) applies.
Referenced documents which are not found to be publicly available in the expected location might be found at
http://docbox.etsi.org/Reference.
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 necessary for the application of the present document.
[1] ETSI TS 102 080: "Transmission and Multiplexing (TM); Integrated Services Digital Network
(ISDN) basic rate access; Digital transmission system on metallic local lines".
[2] ITU-T Recommendation O.9: "Measuring arrangements to assess the degree of unbalance about
earth".
[3] ITU-T Recommendation O.41: "Psophometer for use on telephone-type circuits".
[4] ITU-T Recommendation O.42: "Equipment to measure non-linear distortion using the 4-tone
intermodulation method".
NOTE: Additional references to ITU-T documents can be found in the Bibliography.
[5] ETSI ES 201 970: "Access and Terminals (AT); Public Switched Telephone Network (PSTN);
Harmonized specification of physical and electrical characteristics at a 2-wire analogue presented
Network Termination Point (NTP)".
ETSI
9 ETSI TS 101 952-2 V1.1.1 (2010-11)
[6] ETSI ES 203 021-3: "Access and Terminals (AT); Harmonized basic attachment requirements for
Terminals for connection to analogue interfaces of the Telephone Networks; Update of the
technical contents of TBR 021, EN 301 437, TBR 015, TBR 017; Part 3: Basic Interworking with
the Public Telephone Networks".
NOTE: ETSI TBR 021 has been made historical.
[7] ETSI TS 101 952-1: "Access network xDSL splitters for European deployment; Part 1: Generic
specification of xDSL over POTS splitters".
[8] ETSI TS 101 388: "Access Terminals Transmission and Multiplexing (ATTM); Access
transmission systems on metallic access cables; Asymmetric Digital Subscriber Line (ADSL) -
European specific requirements [ITU-T Recommendation G.992.1 modified]".
2.2 Informative references
The following referenced documents are not necessary for the application of the present document but they assist the
user with regard to a particular subject area.
[i.1] ETSI TR 102 139: "Compatibility of POTS terminal equipment with xDSL systems".
[i.2] ETSI TR 101 728: "Access and Terminals (AT); Study for the specification of low pass filter
section of POTS/ADSL splitters".
[i.3] ETSI TR 101 953-1-1: "Access and Terminals (AT); Unified and Generic Testing Methods for
European Specific DSL splitters; Part 1: ADSL splitters for European deployment; Sub-part 1:
Specification of Testing methods for Low Pass part of ADSL/POTS splitters".
[i.4] ETSI TR 101 953-1-2: "Access network xDSL transmission filters; Part 1: ADSL splitters for
European deployment; Sub-part 2: Testing methods for High Pass part of ADSL/POTS splitters".
[i.5] ETSI TR 101 953-1-3: "Access network xDSL transmission filters; Part 1: ADSL splitters for
European deployment; Sub-part 3: Testing methods for ADSL/ISDN splitters".
[i.6] ETSI TR 101 953-2-1: "Access network xDSL transmission filters; Part 2: VDSL splitters for
European deployment; Sub-part 1: Specification of Testing methods for low pass part of
VDSL/POTS splitters".
[i.7] ETSI TR 101 953-2-2: "Access network xDSL transmission filters; Part 2: VDSL splitters for
European deployment; Sub-part 2: Specification of Testing methods for high pass part of
VDSL/POTS splitters".
[i.8] ETSI TR 101 953-2-3: "Access network xDSL transmission filters; Part 2: VDSL splitters for
European deployment; Sub-part 3: Specification of Testing methods for VDSL/ISDN splitters".
[i.9] ITU-T Recommendation G.992.1: "Asymmetric digital subscriber line (ADSL) transceivers".
[i.10] ITU-T Recommendation G.992.3: "Asymmetric digital subscriber line transceivers 2 (ADSL2)".
[i.11] ITU-T Recommendation G.992.5: "Asymmetric Digital Subscriber Line (ADSL) transceivers -
Extended bandwidth ADSL2 (ADSL2plus)".
[i.12] ITU-T Recommendation G.993.1: "Very high speed digital subscriber line transceivers".
[i.13] ITU-T Recommendation G.993.2: "Very high speed digital subscriber line transceivers 2
(VDSL2)".
[i.14] ETSI TS 101 952-3: "Access, Terminals, Transmission and Multiplexing (ATTM); Access
network xDSL splitters for European deployment; Part 3: Generic specification of distributed
filters for xDSL over POTS".
NOTE: TS 101 952-3 is under construction.
ETSI
10 ETSI TS 101 952-2 V1.1.1 (2010-11)
[i.15] ETSI TS 101 952-4: "Access, Terminals, Transmission and Multiplexing (ATTM); Access
network xDSL splitters for European deployment; Part 4: Additional specifications for dynamic
distributed filters for xDLS over POTS (under study)".
NOTE: TS 101 952-4 is F.F.S.
[i.16] Broadband Forum TR-127: "Dynamic Testing of Splitters and In-Line Filters with xDSL
Transceivers", Issue 1.
NOTE: Available at: http://www.broadband-forum.org/technical/download/TR-127.pdf.
3 Definitions, symbols and abbreviations
3.1 Definitions
For the purposes of the present document, the following terms and definitions apply:
A-wire and B-wire: wires in the 2-wire local loop connection provided from the exchange to the NTP
active splitters: splitters containing some active components, including splitters with "on/off-hook detection" circuitry
central splitter: splitter that is used to isolate xDSL frequencies from POTS or ISDN frequencies at a single point
(often called NTP) at the customer premises (it is also called a master splitter)
dynamic splitter: a splitter changing its transfer behaviour dynamically, e.g. based on the state of the POTS connection
master splitter: See central splitter.
Network Termination Point (NTP): demarcation point between the access pair and the in-house wiring, where often
the central splitter (or master splitter) is placed
off-hook: state of the POTS equipment at either end of a loop connection when the NTP terminal equipment is in the
steady loop state
NOTE: See ES 203 021-3 [6]. In the case where multiple TEs are present at the customer end of the loop, then the
TE is considered to be off-hook from the perspective of testing the splitter when one terminal is off-hook.
on-hook: state of the POTS equipment at either end of a POTS loop connection when the NTP terminal equipment is in
the quiescent state
NOTE: See ES 203 021-3 [6]. In the case where multiple TEs are present at the customer end of the loop, then the
TE is considered to be on-hook from the perspective of testing the splitter only when all of terminals are
on-hook.
passive splitters: splitters containing exclusively passive components
signature network: circuitry included at the POTS port (called TELE port in the present document) of the splitter, the
values and configuration of which may be operator dependent, which has the purpose of enabling network operator's
remote line testing equipment to determine the presence of a splitter on a line
universal splitter: xDSL splitter which can be used with as underlying service either ISDN or POTS below the xDSL
signals
xDSL: this term is an abbreviation, limited to the present document. It covers ADSL and VDSL only. E.g. SDSL is not
covered by this abbreviation
ETSI
11 ETSI TS 101 952-2 V1.1.1 (2010-11)
3.2 Symbols
For the purposes of the present document, the following symbols apply:
NOTE: Check also the clause 3.3 with abbreviations, and note that some symbols might be only used in figures.
Att Attenuation in the xDSL Band (LINE port to xDSL port or reversed)
DB
C DC Blocking capacitor as the optional high pass of first order
DCB
C The capacitor C, part of the Z
DSL DSL-i
CMRR Common Mode Rejection Ratio
f Highest of the used frequencies in the xDSL Band
H
f Lowest of the used frequencies in the xDSL Band
L
f intermediate frequency, e.g. at the US to DS edge for ADSL
M1
f maximum frequency above xDSL band for measurements
Max
IL Insertion Loss xDSL Band Off-Hook
DBOffH
IL Insertion Loss ISDN Band
IB
IL Insertion Loss POTS Pass Band Off-Hook
PBOffH
IL Insertion Loss POTS Pass Band On-Hook
PBOnH
IL Insertion Loss Transition Band, only measured in Off-Hook
TBOffH
IMD InterModulation Distortion in the POTS Band
PB
IMD InterModulation Distortion in the ISDN Band
IB
IMD InterModulation Distortion in the xDSL Band
DB
LCL Longitudinal Conversion Loss
LCL LCL at the LINE port (with either TELE port or xDSL port tied to ground)
LINEport
LCL LCL at the TELE port
TELEport
LCL LCL at the xDSL port
xDSLport
LCTL Longitudinal Conversion Transfer Loss
LCTL LCTL from TELE port to LINE port
TELEtoLINE
L The inductance L, part of the Z
DSL DSL-i
N Noise in the xDSL band
DB
N Noise in the ISDN band
IB
N Noise in the POTS band (psophometric)
PB
R DC resistance between A and B wire
A to B wire
R DC Resistance of a splitter for POTS current
DC
R The resistive R part of the Z (R ≡ Z )
DSL DSL-i DSL RefDSL
R Variable DC feed resistor in figure 3
FEED
RL Return Loss in the ISDN Pass Band
IB
R Variable DC load resistor in figure 4
LOAD
RL Return Loss POTS Pass Band Off-Hook
PBOffH
R Resistance to Earth
to Earth
S Switch to connect xDSL impedance Z to the test set-up
DSL DSL-i
THD Total Harmonic Distortion of the ringing signal
Ring
UaE Unbalance about Earth
V V Ring-Drop
RD
Z Generic name for the AC POTS impedance models
AC
Z Auxiliary AC POTS impedance used in figures F.1 and F.2
AUX
Z Impedance model of the input filter of a particular xDSL over ISDN
DSL-i
Z Alternative impedance model of the input filter of xDSL over ISDN
DSL-i2
Z The input impedance of the splitter at the ringing frequencies
InRing
Z Impedance modelling Line impedance for ISDN purposes
L
Z Impedance modelling Line impedance for ISDN and POTS purposes in the xDSL band
LINE
Z Load impedance, symbol used in figures in clause 5 with test set-ups
LOAD
ETSI
12 ETSI TS 101 952-2 V1.1.1 (2010-11)
Z Impedance modelling POTS On-hook with High Impedance
OnHI
Z Impedance modelling multiple parallel on-hook phones
OnHo
Z Impedance modelling POTS On-hook with Low Impedance
OnLI
Z European harmonized complex reference POTS impedance
R
Z Nominal Reference Design Impedance of xDSL (Z ≡ R )
RefDSL RefDSL DSL
Z Complex POTS impedance, extending Z to higher frequencies,[i.1]
RHF R
Z Impedance modelling the load represented by ringer circuits
Ring
Z Impedance Z Short Loop, modelling a short line terminated on 600 Ω
SL
Z Source impedance, symbol used in figures in clause 5 with test set-ups
SOURCE
Z Impedance modelling the impedance at the TELE port for ISDN purposes
T
3.3 Abbreviations
For the purposes of the present document, the following abbreviations apply:
NOTE: Check also the clause 3.2 with symbols, and note that some abbreviations are only used in the figures.
2B1Q Baseband linecode for ISDN-BRA (4-PAM)
NOTE: See annex A of TS 102 080 [1].
4B3T (also called MMS43) Alternative ISDN-BRA baseband linecode with higher frequency spectrum
than 2B1Q
NOTE: See annex B of TS 102 080 [1].
AC Alternating Current
ADSL Asymmetric Digital Subscriber Line
ADSL1 ADSL limited to 1,1 MHz
NOTE: See ITU-T Recommendation G.992.1 [i.9].
ADSL2 ADSL revision 2
NOTE: See ITU-T Recommendation G.992.3 [i.10].
ADSL2plus ADSL revision "2Plus", extended to 2,2 MHz
NOTE: See ITU-T Recommendation G.992.5 [i.11].
CLIP Calling Line Identification Presentation
CMRR Common Mode Rejection Ratio
CO Central Office (≡ Local Exchange ≡ LE)
CPE Customer Premise Equipment (≡ Terminal Equipment ≡ TE)
CRC Cyclic Redundancy Check
DC Direct Current
DCB DC Blocking
DS Downstream, i.e. from LE side to TE side
DSL Digital Subscriber Line
DSLAM DSL Access Module, equipment at the LE side with multiple DSL transceivers
DUT Device Under Test
e.m.f. Electro-Magnetic Force
F.F.S. For Further Study
FDD Frequency Division Duplexing
HPF High Pass Filter
IL Insertion Loss
IMD InterModulation Distortion
ISDN Integrated Services Digital Network
ISDN-BRA ISDN-Basic Rate Access, 2B + D-channel service with 2B1Q or 4B3T linecode
ITU International Telecommunication Union
LCL Longitudinal Conversion Loss
ETSI
13 ETSI TS 101 952-2 V1.1.1 (2010-11)
LCTL Longitudinal Conversion Transfer Loss
LE Local Exchange (≡ Central Office ≡ CO)
LPF Low Pass Filter
LT Line Termination
MMS43 ≡ 4B3T (an ISDN-BRA baseband linecode)
N.A. Not Applicable
NT Network Termination
NTP Network Termination Point (also see clause 3.1 with definitions.)
PAM Pulse Amplitude Modulation
POTS Plain Old Telephone Service
NOTE: The abbreviation POTS is used in the text of the present document instead of PSTN.
PSTN Public Switched Telephone Network
NOTE: The abbreviation PSTN is replaced by POTS in the text of the present document.
RL Return Loss
RMS, rms Root Mean Square
SDSL Symmetric DSL
SLIC Subscriber Line Interface Circuit
TE Terminal Equipment (≡ CPE) (e.g. Telephone, Fax, voice band modem etc.)
TELE Telephone Equipment, i.e. POTS or ISDN telephone equipment. The TELE port is where ISDN
and optionally POTS equipment is connected at either side of a line
THD Total Harmonic Distortion
UaE Unbalance about Earth
US Upstream, i.e. TE to LE side
US0 Upstream "0" band, the lowest VDSL upstream band
NOTE: See ITU documents [i.12] and [i.13] in the informative references and in the bibliography (Annex N).
VDSL Very high speed Digital Subscriber Line
VDSL1 VDSL variant defined in ITU-T Recommendation G.993.1 [i.12]
VDSL2 VDSL variant defined in ITU-T Recommendation G.993.2 [i.13]
xDSL See under clause 3.1 definitions.
4 General functional description of xDSL over ISDN
splitters and universal splitters
A tutorial on the transmission and separation of POTS, ISDN and xDSL signals is in Annex I.
Merging and separating xDSL and ISDN signals by an xDSL over ISDN splitter or a universal splitter
When ISDN is underlying the xDSL, the main purpose of the xDSL splitter filter is to separate the transmission of
ISDN-BRA signals, and xDSL band signals, enabling the simultaneous transmission of both services on the same
twisted pair. The splitter also serves to protect ISDN from interference due to ingress from xDSL signals. Equally it
protects the xDSL transmission from interference due to the underlying ISDN service.
Insertion of a splitter filter in existing ISDN-BRA lines shall have a limited impact on the performance of the
ISDN-BRA service. The allowed impact is specified in TS 101 388 [8].
Merging and separating xDSL and POTS signals by a universal splitter
When POT
...