ETSI TS 126 131 V14.2.0 (2019-10)

TECHNICAL SPECIFICATION
Universal Mobile Telecommunications System (UMTS);
LTE;
Terminal acoustic characteristics for telephony;
Requirements
(3GPP TS 26.131 version 14.2.0 Release 14)

3GPP TS 26.131 version 14.2.0 Release 14 1 ETSI TS 126 131 V14.2.0 (2019-10)

Reference
RTS/TSGS-0426131ve20
Keywords
LTE,UMTS
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ETSI
3GPP TS 26.131 version 14.2.0 Release 14 2 ETSI TS 126 131 V14.2.0 (2019-10)
Intellectual Property Rights
Essential patents
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pertaining to these essential IPRs, if any, is publicly available for ETSI members and non-members, and can be found
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Legal Notice
This Technical Specification (TS) has been produced by ETSI 3rd Generation Partnership Project (3GPP).
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Modal verbs terminology
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"must" and "must not" are NOT allowed in ETSI deliverables except when used in direct citation.
ETSI
3GPP TS 26.131 version 14.2.0 Release 14 3 ETSI TS 126 131 V14.2.0 (2019-10)
Contents
Intellectual Property Rights . 2
Legal Notice . 2
Modal verbs terminology . 2
Foreword . 7
Introduction . 7
1 Scope . 8
2 References . 8
3 Definitions, symbols and abbreviations . 9
3.1 Definitions . 9
3.2 Abbreviations . 9
4 Interfaces . 10
5 Narrowband telephony transmission performance . 11
5.1 Applicability . 11
5.2 Overall loss/loudness ratings . 11
5.2.1 General . 11
5.2.2 Connections with handset UE . 11
5.2.3 Connections with desktop and vehicle-mounted hands-free UE. 11
5.2.4 Connections with hand-held hands-free UE . 12
5.2.5 Connections with headset UE . 12
5.3 Idle channel noise (handset and headset UE) . 12
5.3.1 Sending . 12
5.3.2 Receiving . 13
5.4 Sensitivity/frequency characteristics . 13
5.4.1 Handset and headset UE sending . 13
5.4.2 Handset and headset UE receiving . 14
5.4.3 Desktop and vehicle-mounted hands-free UE sending . 15
5.4.4 Desktop and vehicle-mounted hands-free UE receiving . 16
5.4.5 Hand-held hands-free UE sending . 17
5.4.6 Hand-held hands-free UE receiving . 18
5.5 Sidetone characteristics (handset and headset UE) . 19
5.5.1 Sidetone loss . 19
5.5.2 Sidetone delay . 19
5.6 Stability loss . 20
5.7 Acoustic echo control . 20
5.7.1 General . 20
5.7.2 Acoustic echo control in desktop and vehicle-mounted hands-free UE . 20
5.7.3 Acoustic echo control in hand-held hands-free UE . 21
5.7.4 Acoustic echo control in a handset UE . 21
5.7.5 Acoustic echo control in a headset UE . 21
5.8 Distortion . 21
5.8.1 Sending distortion . 21
5.8.2 Receiving . 22
5.9 Void . 23
5.10 Information on other parameters (not normative) . 23
5.11 Sending performance in the presence of ambient noise . 23
5.11.1 General . 23
5.11.2 Connections with handset UE . 23
5.11.3 Connections with Handheld hands-free UE . 23
5.12 Delay . 24
5.12.0 UE delay definition . 24
5.12.1 Handset UE . 24
5.12.2 Headset UE . 25
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5.12.2.1 Wired headset . 25
5.12.2.2 Wireless headset . 26
5.13 Echo control characteristics . 26
5.13.1 Handset . 27
5.13.2 Headset . 27
5.13.3 Handheld hands-free . 27
5.13.4 Desktop and vehicle mounted hands-free . 27
5.14 Clock accuracy . 27
5.15 Jitter buffer management behaviour . 28
6 Wideband telephony transmission performance . 28
6.1 Applicability . 28
6.2 Overall loss/loudness ratings . 28
6.2.1 General . 28
6.2.2 Connections with handset UE . 28
6.2.3 Connections with desktop and vehicle-mounted hands-free UE. 29
6.2.4 Connections with hand-held hands-free UE . 29
6.2.5 Connections with headset UE . 29
6.3 Idle channel noise (handset and headset UE) . 30
6.3.1 Sending . 30
6.3.2 Receiving . 30
6.4 Sensitivity/frequency characteristics . 30
6.4.1 Handset and headset UE sending . 30
6.4.2 Handset and headset UE receiving . 31
6.4.3 Desktop and vehicle-mounted hands-free UE sending . 32
6.4.4 Desktop and vehicle-mounted hands-free UE receiving . 33
6.4.5 Hand-held hands-free UE sending . 34
6.4.6 Hand-held hands-free UE receiving . 35
6.5 Sidetone characteristics (handset and headset UE) . 37
6.5.1 Sidetone loss . 37
6.5.2 Sidetone delay . 37
6.6 Stability loss . 37
6.7 Acoustic echo control . 38
6.7.1 General . 38
6.7.2 Acoustic echo control in desktop and vehicle-mounted hands-free UE . 38
6.7.3 Acoustic echo control in hand-held hands-free UE . 38
6.7.4 Acoustic echo control in a handset UE . 38
6.7.5 Acoustic echo control in a headset UE . 39
6.8 Distortion . 39
6.8.1 Sending distortion . 39
6.8.2 Receiving . 40
6.9 Void . 40
6.10 Sending performance in the presence of ambient noise . 41
6.10.1 General . 41
6.10.2 Connections with handset UE . 41
6.10.3 Connections with Handheld hands-free UE . 41
6.11 Delay . 41
6.11.0 UE delay definition . 41
6.11.1 Handset UE . 42
6.11.2 Headset UE . 43
6.11.2.1 Wired headset . 43
6.11.2.2 Wireless headset . 44
6.12 Echo control characteristics . 44
6.12.1 Handset . 45
6.12.2 Headset . 45
6.12.3 Handheld hands-free . 45
6.12.4 Desktop and vehicle mounted hands-free . 45
6.13 Clock accuracy . 45
6.14 Jitter buffer management behaviour . 46
7 Super-wideband telephony transmission performance . 46
7.1 Applicability . 46
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7.2 Overall loss/loudness ratings . 46
7.2.1 General . 46
7.2.2 Connections with handset UE . 46
7.2.3 Connections with desktop and vehicle-mounted hands-free UE. 47
7.2.4 Connections with hand-held hands-free UE . 47
7.2.5 Connections with headset UE . 48
7.3 Idle channel noise (handset and headset UE) . 48
7.3.1 Sending . 48
7.3.2 Receiving . 48
7.4 Sensitivity/frequency characteristics . 49
7.4.0 General . 49
7.4.1 Handset and headset UE sending . 49
7.4.2 Handset and headset UE receiving . 50
7.4.2.1 Handset UE receiving . 50
7.4.2.2 Headset UE receiving . 51
7.4.3 Desktop and vehicle-mounted hands-free UE sending . 52
7.4.4 Desktop and vehicle-mounted hands-free UE receiving . 53
7.4.5 Hand-held hands-free UE sending . 53
7.4.6 Hand-held hands-free UE receiving . 54
7.5 Sidetone characteristics (handset and headset UE) . 55
7.5.1 Sidetone loss . 55
7.5.2 Sidetone delay . 55
7.6 Stability loss . 56
7.7 Acoustic echo control . 56
7.7.1 General . 56
7.7.2 Acoustic echo control in desktop and vehicle-mounted hands-free UE . 56
7.7.3 Acoustic echo control in hand-held hands-free UE . 56
7.7.4 Acoustic echo control in a handset UE . 57
7.7.5 Acoustic echo control in a headset UE . 57
7.8 Distortion . 57
7.8.1 Sending distortion . 57
7.8.2 Receiving . 58
7.9 Void . 59
7.10 Sending performance in the presence of ambient noise . 59
7.10.1 General . 59
7.10.2 Connections with handset UE . 59
7.10.3 Connections with Handheld hands-free UE . 59
7.11 Delay . 60
7.11.0 UE delay definition . 60
7.11.1 Handset UE . 60
7.11.2 Headset UE . 61
7.11.2.1 Wired headset . 61
7.11.2.2 Wireless headset . 63
7.12 Echo control characteristics . 63
7.12.1 Handset . 64
7.12.2 Headset . 64
7.12.3 Handheld hands-free . 64
7.12.4 Desktop and vehicle mounted hands-free . 64
7.13 Clock accuracy . 64
7.14 Jitter buffer management behaviour . 65
8 Fullband telephony transmission performance . 65
8.1 Applicability . 65
8.2 Overall loss/loudness ratings . 65
8.2.1 General . 65
8.2.2 Connections with handset UE . 65
8.2.3 Connections with desktop and vehicle-mounted hands-free UE. 65
8.2.4 Connections with hand-held hands-free UE . 65
8.2.5 Connections with headset UE . 66
8.3 Idle channel noise (handset and headset UE) . 66
8.3.1 Sending . 66
8.3.2 Receiving . 66
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8.4 Sensitivity/frequency characteristics . 66
7.4.0 General . 66
8.4.1 Handset and headset UE sending . 66
8.4.2 Handset and headset UE receiving . 66
8.4.2.1 Handset UE receiving . 66
8.4.2.2 Headset UE receiving . 66
8.4.3 Desktop and vehicle-mounted hands-free UE sending . 66
8.4.4 Desktop and vehicle-mounted hands-free UE receiving . 67
8.4.5 Hand-held hands-free UE sending . 67
8.4.6 Hand-held hands-free UE receiving . 67
8.5 Sidetone characteristics (handset and headset UE) . 67
8.5.1 Sidetone loss . 67
8.5.2 Sidetone delay . 67
8.6 Stability loss . 67
8.7 Acoustic echo control . 67
8.7.1 General . 67
8.7.2 Acoustic echo control in desktop and vehicle-mounted hands-free UE . 67
8.7.3 Acoustic echo control in hand-held hands-free UE . 67
8.7.4 Acoustic echo control in a handset UE . 68
8.7.5 Acoustic echo control in a headset UE . 68
8.8 Distortion . 68
8.8.1 Sending distortion . 68
8.8.2 Receiving . 68
8.9 Void . 68
8.10 Sending performance in the presence of ambient noise . 68
8.10.1 General . 68
8.10.2 Connections with handset UE . 68
8.10.3 Connections with Handheld hands-free UE . 68
8.11 Delay . 68
8.11.0 UE delay definition . 68
8.11.1 Handset UE . 69
8.11.2 Headset UE . 70
8.11.2.1 Wired headset . 70
8.11.2.2 Wireless headset . 71
8.12 Echo control characteristics . 71
8.12.1 Handset . 71
8.12.2 Headset . 71
8.12.3 Handheld hands-free . 71
8.12.4 Desktop and vehicle mounted hands-free . 71
8.13 Clock accuracy . 71
8.14 Jitter buffer management behaviour . 72
Annex A (informative): Change history . 73
History . 76

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3GPP TS 26.131 version 14.2.0 Release 14 7 ETSI TS 126 131 V14.2.0 (2019-10)
Foreword
rd
This Technical Specification has been produced by the 3 Generation Partnership Project (3GPP).
The contents of the present document are subject to continuing work within the TSG and may change following formal
TSG approval. Should the TSG modify the contents of the present document, it will be re-released by the TSG with an
identifying change of release date and an increase in version number as follows:
Version x.y.z
where:
x the first digit:
1 presented to TSG for information;
2 presented to TSG for approval;
3 or greater indicates TSG approved document under change control.
y the second digit is incremented for all changes of substance, i.e. technical enhancements, corrections,
updates, etc.
z the third digit is incremented when editorial only changes have been incorporated in the document.
Introduction
The present document specifies minimum performance requirements for the acoustic characteristics of 3G, LTE, and
WLAN terminals when used to provide narrowband, wideband, super-wideband or fullband telephony.
The objective for narrowband services is to reach a quality as close as possible to ITU-T standards for PSTN circuits.
However, 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 performance requirements are specified in the main body of the text; the test methods and considerations are
described in TS 26.132.
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3GPP TS 26.131 version 14.2.0 Release 14 8 ETSI TS 126 131 V14.2.0 (2019-10)
1 Scope
The present document is applicable to any terminal capable of supporting narrowband, wideband, super-wideband or
fullband telephony, either as a stand-alone service or as the telephony component of a multimedia service. The present
document specifies minimum performance requirements for the acoustic characteristics of 3G, LTE and WLAN
terminals when used to provide narrowband, wideband, super-wideband or fullband telephony.
The set of minimum performance requirements enables a guaranteed level of speech quality while taking possible
physical limits of the terminal design into account. Some performance objectives are also defined, if such design limits
can be overcome. Care must be taken in applying performance objectives in isolation, not to degrade overall end-user
speech quality.
2 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. In the case of a reference to a 3GPP document (including
a GSM document), a non-specific reference implicitly refers to the latest version of that document in the same
Release as the present document.
[1] 3GPP TS 26.132: "Speech and video telephony terminal acoustic test specification".
[2] ITU-T Recommendation B.12 (1988): "Use of the decibel and the neper in
telecommunications"
[3] ITU-T Recommendation G.103 (1998): "Hypothetical reference connections".
[4] ITU-T Recommendation G.111 (1993): "Loudness ratings (LRs) in an international connection".
[5] ITU-T Recommendation G.121 (1993): "Loudness ratings (LRs) of national systems".
[6] ITU-T Recommendation G.122 (1993): "Influence of national systems on stability and talker echo
in international connections".
[7] Void
[8] ITU-T Recommendation P.11 (1993): "Effect of transmission impairments".
[9] ITU-T Recommendation P. 380 (2003): "Electro-acoustic measurements on headsets".
[10] ITU-T Recommendation P.50 (1993): "Artificial voices".
[11] ITU-T Recommendation P.79 (11/07) with Annex G (2001): "Calculation of loudness ratings for
telephone sets".
[12] ITU-T Recommendation G.223 (11/88): "Assumptions for the calculation of noise on hypothetical
reference circuits for telephony".
[13] ITU-T Recommendation P.340 (05/00): "Transmission characteristics and speech quality
parameters of hands-free terminals".
[14] ITU-T Recommendation P.501 (01/12): "Test signals for use in telephonometry".
[15] ITU-T Recommendation P.502 (05/00): "Objective test methods for speech communication
systems using complex test signals".
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3GPP TS 26.131 version 14.2.0 Release 14 9 ETSI TS 126 131 V14.2.0 (2019-10)
[16] 3GPP TS 06.77 (R99): "Minimum Performance Requirements for Noise Suppresser Application to
the AMR Speech Encoder".
[17] 3GPP TS 26.114: "IP Multimedia Subsystem (IMS); Multimedia Telephony; Media handling and
interaction ".
[18] 3GPP TS 23.203: "Policy and charging control architecture".
[19] 3GPP TS 23.402: "Architecture enhancements for non-3GPP accesses".
[20] 3GPP TS 24.302: "Access
...