ETSI EN 300 903 V7.1.1 (2000-11)

Digital cellular telecommunications system (Phase 2+) (GSM); Transmission planning aspects of the speech service in the GSM Public Land Mobile Network (PLMN) system (GSM 03.50 version 7.1.1 Release 1998)

REN/SMG-110350Q7R1

Digitalni celični telekomunikacijski sistem (faza 2+) – Vidiki načrtovanja oddajanja govorne storitve v javnem kopenskem mobilnem omrežju (PLMN) sistema GSM (GSM 03.50, različica 7.1.1, izdaja 1998)

General Information

• Status: Published
• Publication Date: 27-Nov-2000
• Technical Committee: SMG 11 - Speech Aspects
• Current Stage: 12 - Completion
• Due Date: 24-Nov-2000
• Completion Date: 28-Nov-2000
• Ref Project: SIST EN 300 903 V7.1.1:2003 - Digital cellular telecommunications system (Phase 2+) (GSM); Transmission planning aspects of the speech service in the GSM Public Land Mobile Network (PLMN) system (GSM 03.50 version 7.1.1 Release 1998)

Standards Content (Sample)

SLOVENSKI STANDARD
01-december-2003
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JRYRUQHVWRULWYHYMDYQHPNRSHQVNHPPRELOQHPRPUHåMX3/01VLVWHPD*60
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Digital cellular telecommunications system (Phase 2+) (GSM); Transmission planning
aspects of the speech service in the GSM Public Land Mobile Network (PLMN) system
(GSM 03.50 version 7.1.1 Release 1998)
Ta slovenski standard je istoveten z: EN 300 903 Version 7.1.1
ICS:
33.070.50 Globalni sistem za mobilno Global System for Mobile
telekomunikacijo (GSM) Communication (GSM)
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

European Standard (Telecommunications series)

Digital cellular telecommunications system (Phase 2+);
Transmission planning aspects
of the speech service in the GSM
Public Land Mobile Network (PLMN) system
(GSM 03.50 version 7.1.1 Release 1998)
R
GLOBAL SYSTEM FOR
MOBILE COMMUNICATIONS
2 ETSI EN 300 903 V7.1.1 (2000-11)
(GSM 03.50 version 7.1.1 Release 1998)

Reference
REN/SMG-110350Q7R1
Keywords
Digital cellular telecommunications system,
Global System for Mobile communications (GSM)
ETSI
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All rights reserved.
ETSI
3 ETSI EN 300 903 V7.1.1 (2000-11)
(GSM 03.50 version 7.1.1 Release 1998)
Contents
Intellectual Property Rights . 7
Foreword. 7
1 Scope . 8
1.1 References .8
1.2 Abbreviations .10
1.3 Introduction .10
2 Network configurations. 11
2.1 General .11
2.2 Model of the PLMN .11
2.3 Interfaces .11
2.4 Configurations of connections.12
2.4.1 General configurations of connections.12
2.4.2 Reference configurations to illustrate delay and echo control issues.12
2.5 4-wire circuits in the PLMN.12
3 Transmission performance . 13
3.1 Overall Loss/Loudness ratings .13
3.1.1 Connections with handset MSs.14
3.1.2 Connections with handsfree MSs.14
3.1.3 Connections with headset MSs .14
3.2 Stability Loss.15
3.3 Delay .15
3.3.1 General.15
3.3.2 Sources of delay.15
3.3.2.1 Elements of the PLMN that cause delay .15
3.3.2.2 Elements of the PSTN that cause delay.16
3.3.3 Effects of delay .16
3.3.4 Allocation of delay to the PLMN.16
3.3.4.1 Allocation of delay to the PLMN when using a full rate system.16
3.3.4.2 Allocation of delay to the PLMN when using a half rate system.16
3.3.5 Delay of various network configurations.17
3.3.5.1 National and international connections with no echo control in the PSTN (reference
configurations A) .17
3.3.5.2 National and international connections with echo control in the PSTN (reference configurations
B).17
3.3.5.3 Connections where re-routeing leads to a significant increase in transmission path length
(reference configurations C).17
3.3.6 Delay related requirements on the MS.17
3.3.6.1 Full rate MS.17
3.3.6.2 Half rate MS.17
3.3.6.3 Handsfree MS.17
3.4 Echo.18
3.4.1 General.18
3.4.2 Electrical echo control in the PLMN (Reference configurations A).18
3.4.3 Acoustic echo control in the PLMN .18
3.4.3.1 Acoustic echo control in a handsfree MS.19
3.4.3.2 Acoustic echo control in a handset MS .19
3.4.3.3 Acoustic echo control in a headset MS .19
3.4.4 Interaction between tandem echo control devices (reference configurations B & C).19
3.5 Clipping.19
3.5.1 General.19
3.5.2 Properties of voice switches in the PLMN.19
3.5.3 Problems of tandem voice switching .20
3.6 Idle channel noise (handset and headset MS).20
3.6.1 Sending .20
3.6.2 Receiving .20
ETSI
4 ETSI EN 300 903 V7.1.1 (2000-11)
(GSM 03.50 version 7.1.1 Release 1998)
3.7 Noise contrast .20
3.7.1 General.20
3.7.2 Elements of a PLMN which can cause noise contrast impairment .21
3.7.3 Reduction of noise contrast.21
3.7.3.1 Reduction of noise contrast by limiting the noise received by the microphone .21
3.7.3.1.1 Headset MS .21
3.7.3.1.2 Handset MS .22
3.7.3.1.3 Handsfree MS.22
3.7.3.2 Reduction of noise contrast by insertion of comfort noise .22
3.7.4 Consequence of the introduction of high comfort noise levels on other voice-operated devices .22
3.8 Sensitivity/frequency characteristics .22
3.8.1 Headset and Handset MSs .22
3.8.1.1 Sending.22
3.8.1.2 Receiving .23
3.8.2 Handsfree MS .23
3.8.2.1 Sending.23
3.8.2.2 Receiving .24
3.9 Distortion (handset and headset MS).24
3.9.1 Sending .24
3.9.2 Receiving .25
3.10 Sidetone (handset and headset MS).26
3.10.1 Sidetone loss .26
3.10.2 Sidetone distortion .26
3.11 Out-of-band signals .26
3.11.1 Discrimination against out-of-band input signals .26
3.11.1.1 Handset and headset MS .26
3.11.1.2 Handsfree MS.26
3.11.2 Spurious out-of-band signals .27
3.11.2.1 Handset and headset MS .27
3.11.2.2 Handsfree MS.27
3.12 Requirements for information tones .27
3.13 Crosstalk.27
3.13.1 Near and far end crosstalk.27
3.13.2 Go/return crosstalk.28
3.14 MS Ambient Noise Rejection.28
3.14.1 Full-Rate, (TCH-FS) MS Ambient Noise Rejection (handset MS) .28
3.14.2 Full-Rate, (TCH-FS) MS Ambient Noise Rejection (handsfree MS) .28
3.14.3 Half-Rate, (TCH-HS) MS and Dual-Rate (TCH-FS and TCH-HS) MS Ambient Noise Rejection .28
Annex A (informative): Considerations on the Acoustic Interface of the Mobile Station . 37
A.1 Handsfree MS. 37
A.2 Handset MS . 37
A.3 Headset MS . 37
A.4 Inter-reaction with DTX. 37
Annex B (normative): Test considerations.38
B.1 Test signals. 38
B.1.1 Sinusoidal signals .38
B.1.2 Artificial voice.38
B.2 Test signal levels . 38
B.2.1 Sending.38
B.2.1.1 Handset and headset MSs .38
B.2.1.2 Office type Handsfree MS .38
B.2.1.3 Car type Handsfree MS.39
B.2.2 Receiving.39
B.3 Test rooms . 39
B.3.1 Anechoic room .39
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5 ETSI EN 300 903 V7.1.1 (2000-11)
(GSM 03.50 version 7.1.1 Release 1998)
B.4 Test arrangement . 40
B.4.1 Electro-acoustic equipment .40
B.4.2 Test arrangement for handsfree MS .41
B.4.2.1 Office type handsfree MS .41
B.4.2.2 Car type handsfree MS.41
B.4.2.3 Use of HATS for testing the receive characteristics of the car type handsfree MS .42
B.4.2.3.1 Equalization of HATS.42
B.4.2.3.2 Combination of ear signals.43
Annex C (normative): Transmission requirements testing . 44
C.1 Loudness ratings. 44
C.1.1 Sending Loudness Rating (SLR) - Handset MS .44
C.1.2 Sending Loudness Rating (SLR) - Handsfree MS.44
C.1.3 Receiving Loudness Rating (RLR) - Handset MS.44
C.1.4 Receiving Loudness Rating (RLR) - Handsfree MS .45
C.2 Idle Channel Noise . 45
C.2.1 Sending.45
C.2.2 Receiving.45
C.3 Sensitivity/frequency characteristics. 45
C.3.1 Sending - Handset MS.45
C.3.2 Sending - Handsfree MS .46
C.3.3 Receiving - Handset .46
C.3.4 Receiving - Handsfree .47
C.4 Distortion. 47
C.4.1 Sending.47
C.4.2 Receiving.47
C.5 Variation of gain with input level. 48
C.5.1 Sending.48
C.5.2 Receiving.48
C.6 Sidetone. 48
C.6.1 Talker sidetone (STMR).48
C.6.2 Listener sidetone (LSTR) .48
C.7 Sidetone distortion. 49
C.8 Out-of-band signals . 49
C.8.1 Discrimination against out-of-band input signal for handset and headset MS .49
C.8.2 Spurious out-of-band signals for handset and headset MS.49
C.8.3 Discrimination against out-of-band signals for handsfree MS .49
C.8.4 Spurious out-of-band emissions for handsfree MS.49
C.9 Acoustic echo loss . 50
C.9.1 Acoustic echo loss - Handset MS .50
C.9.2 Acoustic echo loss - Handsfree MS.50
C.10 Delay for handsfree MS. 51
C.10.1 Uplink.51
C.10.2 Downlink.51
C.10.3 Result.51
C.11 Ambient noise rejection. 51
C.11.1 Full-Rate, (TCH-FS) MS Ambient Noise Rejection (handset MS).53
C.11.2 Full-Rate, (TCH-FS) MS Ambient Noise Rejection (handsfree MS).53
C.11.3 Half-Rate, (TCH-HS) MS and Dual-Rate (TCH-FS and TCH-HS) MS Ambient Noise Rejection.53
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6 ETSI EN 300 903 V7.1.1 (2000-11)
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Annex D (normative): MS delay requirement definition. 54
D.1 Full rate MS delay requirement definition . 54
D.2 Half rate MS delay requirement definition. 55
Annex E (informative): Adaptive gain control . 56
Annex F (informative): Change Request History. 57
History . 58

ETSI
7 ETSI EN 300 903 V7.1.1 (2000-11)
(GSM 03.50 version 7.1.1 Release 1998)
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://www.etsi.org/ipr).
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 European Standard (Telecommunications series) has been produced by ETSI Technical Committee Special Mobile
Group (SMG).
The present document describes the transmission planning aspects pertaining to the speech service within the digital
cellular telecommunications system (Phase 2+).
The contents of the present document is subject to continuing work within SMG and may change following formal
SMG approval. Should SMG modify the contents of the present document it will be re-released with an identifying
change of release date and an increase in version number as follows:
Version 7.x.y
where:
7 indicates Release 1998 of GSM Phase 2+.
x the second digit is incremented for all changes of substance, i.e. technical enhancements, corrections,
updates, etc.
y the third digit is incremented when editorial only changes have been incorporated in the specification.

National transposition dates
Date of adoption of this EN: 17 November 2000
Date of latest announcement of this EN (doa): 28 February 2001
Date of latest publication of new National Standard
or endorsement of this EN (dop/e): 31 August 2001
Date of withdrawal of any conflicting National Standard (dow): 31 August 2001

ETSI
8 ETSI EN 300 903 V7.1.1 (2000-11)
(GSM 03.50 version 7.1.1 Release 1998)
1 Scope
The present document describes the transmission planning aspects pertaining to the speech service in the GSM PLMN
system. Due to technical and economic factors, there cannot be full compliance with the general characteristics of
international telephone connections and circuits recommended by the ITU-T.
The present document gives guidance as to the precautions, measures and minimum requirements needed for successful
interworking of the PLMN with the national and international PSTN. The present document identifies a number of
routeing and network configurations. The objective is to reach a quality as close as possible to ITU-T standards in order
to safeguard the performance seen by PSTN customers.
1.1 References
The following documents contain provisions which, through reference in this text, constitute provisions of the present
document.
• References are either specific (identified by date of publication, edition number, version number, etc.) or
non-specific.
• For a specific reference, subsequent revisions do not apply.
• For a non-specific reference, the latest version applies.
• A non-specific reference to an ETS shall also be taken to refer to later versions published as an EN with the same
number.
• For this Release 1998 document, references to GSM documents are for Release 1998 versions (version 7.x.y).
[1] GSM 01.04: "Digital cellular telecommunications system (Phase 2+); Abbreviations and
acronyms".
[2] GSM 03.04: "Digital cellular telecommunications system (Phase 2+); Signalling requirements
relating to routeing of calls to mobile subscribers".
[3] GSM 06.01: "Digital cellular telecommunications system (Phase 2+); Full rate speech processing
functions".
[4] GSM 06.10: "Digital cellular telecommunications system (Phase 2+); Full rate speech;
Transcoding".
[5] GSM 06.11: "Digital cellular telecommunications system (Phase 2+); Full rate speech;
Substitution and muting of lost frames for full rate speech channels".
[6] GSM 06.12: "Digital cellular telecommunications system (Phase 2+); Full rate speech; Comfort
noise aspect for full rate speech traffic channels".
[7] GSM 06.31: "Digital cellular telecommunications system (Phase 2+); Full rate speech;
Discontinuous Transmission (DTX) for full rate speech traffic channels".
[8] GSM 06.32: "Digital cellular telecommunications system (Phase 2+); Voice Activity Detection
(VAD)".
[9] GSM 06.02: "Digital cellular telecommunications system (Phase 2+); Half rate speech; Half rate
speech processing functions".
[10] GSM 06.20: "Digital cellular telecommunications system (Phase 2+); Half rate speech; Half rate
speech transcoding".
[11] GSM 06.21: "Digital cellular telecommunications system (Phase 2+); Half rate speech;
Substitution and muting of lost frames for half rate speech traffic channels".
ETSI
9 ETSI EN 300 903 V7.1.1 (2000-11)
(GSM 03.50 version 7.1.1 Release 1998)
[12] GSM 06.22: "Digital cellular telecommunications system (Phase 2+); Half rate speech; Comfort
noise aspects for half rate speech traffic channels".
[13] GSM 06.41: "Digital cellular telecommunications system (Phase 2+); Half rate speech;
Discontinuous Transmission (DTX) for half rate speech traffic channels".
[14] GSM 06.42: "Digital cellular telecommunications system (Phase 2+); Half rate speech; Voice
Activity Detection (VAD) for half rate speech traffic channels".
[15] I-ETS 300 245-2: "Integrated Services Digital Network (ISDN): Technical characteristics of
telephony terminals: Part 2: PCM A-Law handset telephony".
[16] ITU-T Recommendation G.103 (1998): "Hypothetical reference connections".
[17] ITU-T Recommendation G.111 (1993): "Loudness ratings (LRs) in an international connection".
[18] ITU-T Recommendation G.113 (1993): "Transmission impairments".
[19] ITU-T Recommendation G.114 (1993): "Mean one-way propagation time".
[20] ITU-T Recommendation G.121 (1993): "Loudness ratings (LRs) of national systems".
[21] ITU-T Recommendation G.122 (1993): "Influence of national systems on stability, talker echo,
and listener echo in international connections".
[22] ITU-T Recommendation G.131 (1988): "Stability and echo".
[23] ITU-T Recommendation G.165 (1993): "Echo cancellers".
[24] ITU-T Recommendation G.223 (1988): "Assumptions for the calculation of noise on hypothetical
reference circuits for telephony".
[25] ITU-T Recommendation G.703 (1991): "Physical/electrical characteristics of hierarchical digital
interfaces".
[26] ITU-T Recommendation G.711 (1988): "Pulse code modulation (PCM) of voice frequencies".
[27] ITU-T Recommendation G.712 (1992): "Transmission performance characteristics of pulse code
modulation".
[28] ITU-T Recommendation G.167 (1993): "Acoustic Echo Controllers".
[29] ITU-T Recommendation M.1020 (1993): "Characteristics of special quality international leased
circuits with special bandwidth conditions".
[30] ITU-T Recommendation M.1025 (1993): "Characteristics of special quality international leased
circuits with basic bandwidth conditioning".
[31] ITU-T Recommendation M.1030 (1988): "Characteristics of ordinary quality international leased
circuits forming part of private switched telephone networks".
[32] ITU-T Recommendations M.1040 (1988): "Characteristics of ordinary quality international leased
circuits".
[33] ITU-T Recommendation O.132 (1988): "Specification for a quantizing distortion measuring
apparatus using a sinusoidal test signal".
[34] ITU-T Recommendation P.11 (1993): "Effect of transmission impairments".
[35] ITU-T Recommendation P.34 (1993): "Transmission characteristics of hands-free telephones".
[36] ITU-T Recommendation P.38 (1993): "Transmission characteristics of operator telephone systems
(OTS)".
[37] ITU-T Recommendation P.50 (1993): "Artificial voices".
[38] ITU-T Recommendation P.51 (1993): "Artificial mouths".
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10 ETSI EN 300 903 V7.1.1 (2000-11)
(GSM 03.50 version 7.1.1 Release 1998)
[39] ITU-T Recommendation P.64 (1993): "Determination of sensitivity/frequency characteristics of
local telephone".
[40] ITU-T Recommendation P.76 (1988): "Determination of loudness ratings; fundamental
principles".
[41] ITU-T Recommendation P.79 (1993): "Calculation of loudness ratings".
[42] ITU-T Recommendation Q.35 (1988): "Technical characteristics of tones for the telephone
service".
[43] ITU-T Recommendation Q.551 (1994): "Transmission characteristics of digital exchanges".
[44] ITU-T Blue Book (1988): "Volume V, Supplement 13: Noise spectra".
[45] ISO 3 - 1973: "Preferred numbers - series of preferred numbers".
[46] ITU-T Recommendation P.57 (1996): "Artificial Ears".
[47] ITU-T Recommendation P.58 (1993): "Head and Torso Simulator for Telephonometry".
[48] I-ETS 300 245-3: "Integrated Services Digital Network (ISDN): Technical characteristics of
telephony terminal: Part 3: PCM A-law loudspeaking and handsfree telephony".
1.2 Abbreviations
In addition to those below, the abbreviations used in the present document are listed in GSM 01.04.
ADC Analogue to Digital Converter
ADPCM Adaptive Differential Pulse Code Modulation
AEC Acoustic Echo Control
BSC Base Station Controller (excluding transmission systems
BTS Base Transceiver Station (excluding transmission systems)
DAC Digital to Analogue Converter
DMR Digital Mobile Radio
DSI Digital Speech Interpolation
EEC Electric Echo Control
EL Echo Loss
ERP Ear Reference Point
FDM Frequency Division Multiplex
ISC International Switching
LE Local Exchange
LSTR Listener Sidetone Rating
MRP Mouth Reference Point
OLR Overall Loudness Rating
PCM Pulse Code Modulation
POI Point of Interconnection (with PSTN)
RLR Receiver Loudness Rating
SLR Send Loudness Rating
STMR Sidetone Masking Rating
UPCMI 13-bit Uniform PCM Interface
1.3 Introduction
Since the transmission quality and the conversational quality of the PLMN will in general be lower than the quality of
the PSTN connection due to coding distortion, delay, etc., only some transmission aspects can be brought in line with
ITU-T Recommendations. It is therefore necessary to improve the overall quality as much as possible by implementing
proper routeing and network configurations.
It should be recognized that the transmission plan for the GSM PLMN cannot lead to major changes in the PSTN.
However, it is important to use the improvements in the evolving PSTN (e.g. digitalization, introduction of echo
cancellers) in an effective way.
ETSI
11 ETSI EN 300 903 V7.1.1 (2000-11)
(GSM 03.50 version 7.1.1 Release 1998)
The transmission requirements are in the first place based on international connections. When the quality is sufficient
for international connections, it can be assumed that the national connections will have the same or better quality.
In order to obtain a sufficient quality in the connection, it is preferable to have digital connectivity between the Base
Station System (BSS) and the international exchange. The PLMN requirements are based on this assumption. When this
situation cannot be provided, a lower quality must temporarily be accepted.
The present document consists of two parts: one will deal with network configurations, the other with transmission
performance.
The part about network configurations gives information about the reference connections, on which the transmission
plan is based. Furthermore, some guidelines are presented for improvement of the transmission quality in the evolving
(digital) PSTN.
The part about transmission performance gives mainly characteristics of the transmission between MS acoustic
interface (MRP/ERP) and the interface between the PLMN and the PSTN (POI). For transmission aspects where it is
impossible to give overall characteristics, it is in some cases necessary to make recommendations for individual parts of
the equipment.
Annex A considers the effects of the type of acoustic interfaces of the MS.
2 Network configurations
2.1 General
The basic configuration for the interworking with the PSTN is shown in figure 1.
2.2 Model of the PLMN
A more detailed model of the PLMN used for the consideration of transmission planning issues for speech is shown in
figure 2. This model represents the main functions required and does not necessarily imply any particular physical
realization. Routeing of calls is given in GSM 03.04.
Any acoustic echo control is not specifically shown as it will be provided by analogue processing of digital processing
or a combination of both techniques.
2.3 Interfaces
The main interfaces identified within the GSM specifications are shown in figure 1. For the purposes of the present
document, the Air Interface and the Point of Interconnect (POI) are identified along with two other interfaces, Interface
Z and a 13-bit Uniform PCM Interface (UPCMI). These interfaces are needed to define the PLMN transmission
characteristics and the overall system requirements.
The Air Interface is specified by GSM 05 series specifications and is required to achieve MS transportability. Analogue
measurements can be made at this point by using the appropriate radio terminal equipment and speech transcoder. The
losses and gains introduced by the test speech transcoder will need to be specified.
The POI with the PSTN will generally be at the 2 048 kbits/s level at an interface, in accordance with ITU-T
Recommendation G.703. At the point, which is considered to have a relative level of O dBr, the analogue signals will
be represented by 8-bit A-law, according to ITU-T Recommendation G.711. Analogue measurements may be made at
this point using a standard send and receive side, as defined in ITU-T Recommendations.
Interface Z might be used in the case of direct MSC to MSC connections. Interface Z is of the same nature as the POI.
The UPCMI is introduced for design purposes in order to separate the speech transcoder impairments from the basic
audio impairments of the MS.
ETSI
12 ETSI EN 300 903 V7.1.1 (2000-11)
(GSM 03.50 version 7.1.1 Release 1998)
2.4 Configurations of connections
2.4.1 General configurations of connections
Figure 3 shows a variety of configurations of connections. There are a number of PSTN features which should be
avoided from such connections. These include:
- echo control devices in the international network. If present, and not disabled, these devices will be in tandem
with PLMN echo cancellers and may introduce degradation;
- satellite routeings. The delay inherent in the connections when added to the PLMN delay, may result in
conversational difficulties. Double satellite links are likely to cause severe difficulties and special precautions
should be taken to avoid this situation under call forwarding arrangements;
- Digital Speech Interpolation systems (DSI). There is likely to be an adverse interaction between DSI and DTX;
- ADPCM. The distortion introduced by ADPCM on routes where PSTN echo control is not provided is likely to
reduce the echo cancellation provided by the PLMN electric echo canceller;
- significant differences in clock rates on non-synchronized digital network components. The resulting phase roll
and slips are likely to degrade the performance of the PLMN echo canceller;
- those analogue FDM routeings which exhibit phase roll. Any phase roll due to t
...