ETSI TS 126 103 V16.0.0 (2020-11)

Digital cellular telecommunications system (Phase 2+) (GSM); Universal Mobile Telecommunications System (UMTS); Speech codec list for GSM and UMTS (3GPP TS 26.103 version 16.0.0 Release 16)

RTS/TSGS-0426103vg00

General Information

• Status: Not Published
• Technical Committee: 3GPP SA 4 - Codec
• Current Stage: 12 - Completion
• Completion Date: 18-Nov-2020

Standards Content (Sample)

ETSI TS 126 103 V16.0.0 (2020-11)






TECHNICAL SPECIFICATION
Digital cellular telecommunications system (Phase 2+) (GSM);
Universal Mobile Telecommunications System (UMTS);
Speech codec list for GSM and UMTS
(3GPP TS 26.103 version 16.0.0 Release 16)

R
GLOBAL SYSTEM FOR
MOBILE COMMUNICATIONS

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3GPP TS 26.103 version 16.0.0 Release 16 1 ETSI TS 126 103 V16.0.0 (2020-11)



Reference
RTS/TSGS-0426103vg00
Keywords
GSM,UMTS
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3GPP TS 26.103 version 16.0.0 Release 16 2 ETSI TS 126 103 V16.0.0 (2020-11)
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
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ETSI

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3GPP TS 26.103 version 16.0.0 Release 16 3 ETSI TS 126 103 V16.0.0 (2020-11)
Contents
Intellectual Property Rights . 2
Legal Notice . 2
Modal verbs terminology . 2
Foreword . 4
1 Scope . 5
2 Normative references . 5
3 Definitions and Abbreviations . 7
3.1 Definitions . 7
3.2 Abbreviations . 7
4 General . 8
5 3GPP Codec List for OoBTC in a BICC-based Circuit Switched Core Network and for AoIP . 10
5.1 GSM Full Rate Codec Type (GSM FR) . 10
5.2 GSM Half Rate Codec Type (GSM HR) . 10
5.3 GSM Enhanced Full Rate Codec Type (GSM EFR) . 10
5.4 Five Adaptive Multi-Rate Codec Types (FR AMR, HR AMR, UMTS AMR, UMTS AMR2, OHR
AMR) . 11
5.5 TDMA Enhanced Full Rate Codec Type (TDMA EFR) . 14
5.6 PDC Enhanced Full Rate Codec Type (PDC_EFR) . 14
5.7 Four Adaptive Multi-Rate Wideband Codec Types (FR AMR-WB, UMTS AMR-WB, OFR AMR-WB,

OHR AMR-WB) . 14
5.7A EVS Codec Type (UMTS_EVS) . 17
5.8 MuMe Dummy Codec (3G.324M) . 20
5.9 MuMe2 Dummy Codec (3G.324M2) . 20
5.10 Codec Extension . 20
5.11 CSData Dummy Codec (AoIP) . 21
6 Codec List for the Call Control Protocol . 21
6.1 System Identifiers for GSM and UMTS . 21
6.2 Codec Bitmap . 21
6.3 Selected Codec Type . 22
7 3GPP Codecs for OoBTC in a SIP-I -based Circuit Switched Core Network . 23
7.1 Overview . 23
7.2 AMR . 23
7.3 AMR-WB . 24
7.4 GSM_EFR . 24
7.5 GSM_FR . 24
7.6 GSM_HR . 24
7.7 PCM . 25
7.8 Telephone-Event . 25
7.9 EVS . 25
Annex A (informative): Example Supported Codec List for UMTS . 26
Annex B (informative): Change history . 28
History . 29

ETSI

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3GPP TS 26.103 version 16.0.0 Release 16 4 ETSI TS 126 103 V16.0.0 (2020-11)
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.
ETSI

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3GPP TS 26.103 version 16.0.0 Release 16 5 ETSI TS 126 103 V16.0.0 (2020-11)
1 Scope
The present Technical Specification outlines the Codec Lists in 3GPP including both systems, GSM and UMTS, to be
used by the Out of Band Transcoder Control (OoBTC) protocol to set up a call or modify a call in Transcoder Free
Operation (TrFO) and in "transcoder at the edge" scenarios.
The TS also specifies the SDP description of 3GPP Codecs to be used within a SIP-I -based circuit switched core
network as specifies in 3GPP TS 23.231 [14].
The TS further specifies the coding of the Supported Codec List Information Elements for the UMTS radio access
technology.
The TS further reserves the Code Point for the CSData (dummy) Codec Type for the negotiation of A-Interface Type
and the RTP redundancy for CS Data and Fax services, see 3GPP TS 48.008 [23].
The Supported Codec List IE includes Codec_Types from the TDMA and PDC systems, to support TFO or TrFO
between UMTS and TDMA, or UMTS and PDC.
2 Normative 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 26.090: "AMR Speech Codec; Speech Transcoding Functions".
[2] 3GPP TS 26.093: "AMR Speech Codec; Source Controlled Rate Operation".
[3] 3GPP TS 26.101: "Mandatory Speech Codec Speech Processing Functions; AMR Speech Codec
Frame Structure".
[4] 3GPP 46.0xx: "Enhanced Full Rate Codec Recommendations".
[5] 3GPP 26.0xx: "Adaptive Multi-Rate Codec Recommendations".
[6] "ITU Q.765.5: "Use of Application Transport Mechanism for Bearer Independent Call Control"
[7] 3GPP TS 28.062: "In-band Tandem Free Operation (TFO) of Speech Codecs, Stage 3 - Service
Description".
[8] 3GPP TS 23.153: "Out of Band Transcoder Control - Stage 2".
[9] 3GPP TS 24.008: "Mobile radio interface layer 3 specifications, Core Network Protocols"
[10] 3GPP TS 26.190: "AMR Wideband Speech Codec; Speech Transcoding Functions".
[11] 3GPP TS 26.193: "AMR Wideband Speech Codec; Source Controlled Rate Operation".
[12] 3GPP TS 26.201: "Mandatory Speech Codec Speech Processing Functions; AMR Wideband
Speech Codec Frame Structure".
[13] 3GPP TS 23.172: "CS multimedia service UDI/RDI fallback and service modification; Stage 2".
[14] 3GPP TS 23.231: "SIP-I based circuit-switched core network; Stage 2".
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3GPP TS 26.103 version 16.0.0 Release 16 6 ETSI TS 126 103 V16.0.0 (2020-11)
[15] 3GPP TS 29.007: "General requirements on interworking between the Public Land Mobile
Network (PLMN) and the Integrated Services Digital Network (ISDN) or Public Switched
Telephone Network (PSTN)".
[16] IETF RFC 3264 (2002): "An Offer/Answer Model with the Session Description Protocol (SDP)",
J. Rosenberg and H. Schulzrinne.
[17] IETF RFC 3551 (2003): "RTP Profile for Audio and Video Conferences with Minimal Control",
H. Schulzrinne and S. Casner.
[18] void
[19] IETF RFC 4566 (2006): "SDP: Session Description Protocol", M. Handley, V. Jacobson and C.
Perkins.
[20] IETF RFC 4733 (2006): "RTP Payload for DTMF Digits, Telephony Tones, and Telephony
Signals", H. Schulzrinne and T.Taylor.
[21] IETF RFC 4867 (2007): "RTP Payload Format and File Storage Format for the Adaptive Multi-
Rate (AMR) and Adaptive Multi-Rate Wideband (AMR-WB) Audio Codecs", J. Sjoberg, M.
Westerlund, A. Lakaniemi and Q. Xie.
[22] IETF RFC 5993 (2010) "RTP Payload Format for Global System for Mobile Communications
Half Rate (GSM-HR)".
[23] 3GPP TS 48.008: "Mobile Switching Centre - Base Station System (MSC-BSS) interface".
[24] 3GPP TS 26.102: "Adaptive Multi-Rate (AMR) speech codec; Interface to Iu, Uu and Nb".".
[25] 3GPP TS 26.441: "Codec for Enhanced Voice Services (EVS); General overview".
[26] 3GPP TS 26.442: "Codec for Enhanced Voice Services (EVS); ANSI C code (fixed-point)".
[27] 3GPP TS 26.443: "Codec for Enhanced Voice Services (EVS); ANSI C code (floating-point)".
[28] 3GPP TS 26.444: "Codec for Enhanced Voice Services (EVS); Test Sequences".
[29] 3GPP TS 26.445: "Codec for Enhanced Voice Services (EVS); Detailed algorithmic description".
[30] 3GPP TS 26.446: "Codec for Enhanced Voice Services (EVS); Adaptive Multi-Rate - Wideband
(AMR-WB) backward compatible functions".
[31] 3GPP TS 26.447: "Codec for Enhanced Voice Services (EVS); Error concealment of lost packets".
[32] 3GPP TS 26.448: "Codec for Enhanced Voice Services (EVS); Jitter buffer management".
[33] 3GPP TS 26.449: "Codec for Enhanced Voice Services (EVS); Comfort Noise Generation (CNG)
aspects".
[34] 3GPP TS 26.450: "Codec for Enhanced Voice Services (EVS); Discontinuous Transmission
(DTX)".
[35] 3GPP TS 26.451: "Codec for Enhanced Voice Services (EVS); Voice Activity Detection (VAD)".
[36] 3GPP TR 26.952: "Codec for Enhanced Voice Services (EVS); Performance Characterization".
[37] 3GPP TS 26.453: "Codec for Enhanced Voice Services (EVS); Speech codec frame structure".
[38] 3GPP TS 26.454: "Codec for Enhanced Voice Services (EVS); Interface to Iu, Uu, Nb and Mb".
[39] 3GPP TS 29.163: "Interworking between the IP Multimedia (IM) Core Network (CN) subsystem
and Circuit Switched (CS) networks".
[40] 3GPP TS 26.452: "Codec for Enhanced Voice Services (EVS); ANSI C code; Alternative fixed-
point using updated basic operators".
ETSI

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3GPP TS 26.103 version 16.0.0 Release 16 7 ETSI TS 126 103 V16.0.0 (2020-11)
3 Definitions and Abbreviations
3.1 Definitions
Codec Type: defines a specific type of a speech Coding algorithm, applied on a specific radio access technology (e.g.
GSM FR, (GSM) FR AMR).
Codec Mode: defines a specific mode of a Codec Type (e.g. 12,2 kBit/s Mode of the (GSM) FR AMR).
Codec Configuration: defines a specific set of attributes to a certain Codec Type (e.g. the combination of ACS and
DTX="on" for (GSM) FR AMR).
Organisation Identifier (OID): Identifies the standard organisation (e.g. 3GPP) producing a specification for a Codec
List. ITU-T is responsible for maintaining the list of Organisation Identifiers.
System Identifier (SysID): Identifies the radio access technology (e.g. GSM or UMTS) for which the supported Codec
List is defined.
Other definitions are given in TS 23.153 [8].
3.2 Abbreviations
For the purposes of the present document, the following abbreviations apply:
ACS Active Codec (mode) Set
AoIP A-Interface User Plane over IP
BWM BandWidth Multiplier
CMR Codec Mode Request (for AMR and AMR-WB)
CoID Codec IDentifier
CS Circuit Switched
CSData Circuit Switched Data and Fax dummy Codec
DTX Discontinuous Transmission (of speech and audio signals, synonym to SCR)
EVS Enhanced Voice Services
EVS-CMR Codec Mode Request for EVS
FB Fullband (audio bandwidth)
GSM Global System for Mobile communication
MuMe Multi-Media
NB Narrowband (audio bandwidth)
NboIP Nb-Interface User Plane transport over IP in a SIP-I -based network
OID Organisation IDentifier (e.g. ITU-T, 3GPP)
OoBTC Out of Band Transcoder Control
PDC Personal Digital Communication (synonym for .)
RX Receive
SCR Source Controlled Rate operation (synonym to DTX )
ETSI

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3GPP TS 26.103 version 16.0.0 Release 16 8 ETSI TS 126 103 V16.0.0 (2020-11)
SID Silence Descriptor
SWB Super Wideband (audio bandwidth)
SysID System Identifier
TDMA Time Division Multiple Access (synonym for .)
TFO Tandem Free Operation
(also sometimes called "Transcoder-Through" or "Codec-Bypass")
TrFO Transcoder Free Operation
TX Transmit
UMTS Universal Mobile Telecommunications System
WB Wideband (audio bandwidth)
4 General
The present Technical Specification (TS) outlines the 3GPP internal Codec Lists for both, GSM and UMTS, to be used
by the Out of Band Transcoder Control (OoBTC) protocol a BICC-based Circuit Switched Core Network to set up a
call or modify a call in Transcoder Free Operation (TrFO). The Codec List is also used in the Codec Negotiation for the
A-Interface User Plane over IP (AoIP), see 3GPP TS 48.008 [23].
The TS specifies the SDP parameters for the 3GPP Codecs for OoBTC in a SIP-I -based Circuit Switched Core
Network, see 3GPP TS 23.231 [14].
The TS further specifies the coding of the Supported Codec List Information Elements as defined in 3GPP TS 24.008
for the UMTS radio access technology.
Transcoder Free Operation allows the transport of speech signals in the coded domain from one user equipment (UE) to
the other user equipment through the radio access network (RAN) and core network (CN), possibly through a transit
network (TN). This enables high speech quality, low transmission costs and high flexibility.
The necessary Codec Type selection and resource allocation are negotiated out of band before and after call setup.
Possible Codec (re-)configuration, Rate Control and DTX signalling may be performed after call setup by additional
inband signalling or a combination of inband and out-of-band signalling.
Up to release '99 GSM does not support Transcoder Free Operation, but specifies the Tandem Free Operation (TFO).
Tandem Free Operation enables similar advantages, but is based on pure inband signalling after call setup.
The parameters defined in this Technical Specification allow interaction between TrFO and TFO. They further provide
an evolutionary path for GSM towards Transcoder Free Operation.
The GERAN and UTRAN standards define fourteen different Speech Codec Types, see table 4.1.
In addition to these Speech Codec Types some "dummy" Codec Types are defined to support the negotiation for data,
fax and multimedia applications.
ETSI

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3GPP TS 26.103 version 16.0.0 Release 16 9 ETSI TS 126 103 V16.0.0 (2020-11)
Table 4.1: Support of Codec Types in Radio Access Technologies

TDMA UMTS UMTS (GSM) (GSM) GSM GSM GSM
EFR AMR 2 AMR HR AMR FR AMR EFR HR FR
CoID 0x07 0x06 0x05 0x04 0x03 0x02 0x01 0x00
not not not yes, yes, yes yes yes
GERAN
defined possible possible 1.4 modi 1.4 modi
GMSK

not not not not not not not not
GERAN
defined possible possible defined defined defined defined defined
8PSK

not yes, R99, not not not not not
UTRAN
defined 1.8 modi UTRAN- defined defined defined defined defined
1.4 modi only UEs
recomm.


Codec UMTS OHR OFR OHR UMTS FR PDC
Extension EVS AMR-WB AMR-WB AMR AMR-WB AMR-WB EFR
CoID 0x0F 0x0E 0X0D 0x0C 0x0B 0x0A 0x09 0x08
GERAN reserved not not not not not yes3 not
GMSK defined defined defined defined possible modi defined

GERAN reserved not yes, yes, yes, not not not
8PSK defined 3 modi 3 modi 1.4 possible defined defined
modi
UTRAN reserved yes not not not yes not not
defined defined defined 3.4 defined defined
modi

CoID is reprinted here in hexadecimal notation. It is defined in section 5.
Up to date the following Code Points are defined:
Table 4.2. Defined Code Points
Hexadecimal Binary Codec Name Remark
Notation Notation
0x00h 0x0000.0000 GSM_FR
0x01h 0x0000.0001 GSM_HR
0x02h 0x0000.0010 GSM_EFR
0x03h 0x0000.0011 (GSM) FR_AMR
0x04h 0x0000.0100 (GSM) HR_AMR
0x05h 0x0000.0101 UMTS_AMR
0x06h 0x0000.0110 UMTS_AMR2
0x07h 0x0000.0111 TDMA_EFR
0x08h 0x0000.1000 PDC_EFR
0x09h 0x0000.1001 (GSM) FR_AMR-WB
0x0Ah 0x0000.1010 UMTS_AMR-WB
0x0Bh 0x0000.1011 OHR_AMR
0x0Ch 0x0000.1100 OFR_AMR-WB
0x0Dh 0x0000.1101 OHR_AMR-WB
0x0Eh 0x0000.1110 UMTS_EVS
0x0Fh 0x0000.1111 Codec Extension For AoIP and TFO

0x10h … 0x0001.0000 Spare, for future use
0xFCh …
0x1111.1100

0xFDh 0x1111.1101 CSData For AoIP only
0xFEh 0x1111.1110 MuMe2 For OoBTC only
0xFFh 0x1111.1111 MuMe For OoBTC only

ETSI

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3GPP TS 26.103 version 16.0.0 Release 16 10 ETSI TS 126 103 V16.0.0 (2020-11)
5 3GPP Codec List for OoBTC in a BICC-based Circuit
Switched Core Network and for AoIP
The definition of the common Codec List for Out of Band Transcoder Control (3GPP TS 23.153, [8]) in 3GPP for
GSM and UMTS follows the specifications given in ITU Q.765.5: The most preferred Codec Type is listed first,
followed by the second preferred one, and so on. An informative example for a codec list for UMTS can be found in
Annex A.
The Codec IDentification codes (CoIDs) are specified in two versions: the long form (8 bits) for the use in OoBTC and
the short form (the 4 LSBs of the long form) for the use in TFO and AoIP.
5.1 GSM Full Rate Codec Type (GSM FR)
The Codec IDentification (CoID) code is defined to be: FR_CoID := 0x0000.0000.
The GSM Full Rate Codec Type has no additional parameters.
For information (for exact details see GSM Recommendations):
The GSM Full Rate Codec Type supports one fixed Codec Mode with 13.0 kBit/s.
DTX may be enabled in uplink and in downlink independently of each other. DTX on or off is defined by the network
on a cell basis and can not be negotiated at call setup or during the call. The DTX scheme uses one SID frame to mark
the end of a speech burst and to start Comfort Noise Generation. Identical SID frames for comfort noise updates are sent
in speech pauses about every 480 ms, aligned with the cell's TDMA frame structure. The defined Tandem Free
Operation allows the reception of GSM FR DTX information for the downlink direction in all cases. The TFO
respectively TrFO partner is prepared to receive DTX information as well.
5.2 GSM Half Rate Codec Type (GSM HR)
The Codec IDentification (CoID) code is defined to be: HR_CoID := 0x0000.0001.
The GSM Half Rate Codec Type has no additional parameters.
For information (for exact details see GSM Recommendations):
The GSM Half Rate Codec Type supports one fixed Codec Mode with 5.60 kBit/s.
DTX may be enabled in uplink and in downlink independently of each other. DTX on or off is defined by the network
on a cell basis and can not be negotiated at call setup or during the call. The DTX scheme uses one SID frame to mark
the end of a speech burst and to start Comfort Noise Generation. Identical SID frames for comfort noise updates are sent
in speech pauses about every 480 ms, aligned with the cell's TDMA frame structure. The defined Tandem Free
Operation allows the reception of GSM HR DTX information for the downlink direction in all cases. The TFO
respectively TrFO partner shall be prepared to receive DTX information as well.
5.3 GSM Enhanced Full Rate Codec Type (GSM EFR)
The Codec IDentification (CoID) code is defined to be: EFR_CoID := 0x0000.0010.
The GSM Enhanced Full Rate Codec Type has no additional parameters.
For information (for exact details see GSM Recommendations):
The GSM Enhanced Full Rate Codec Type supports one fixed Codec Mode with 12.2 kBit/s.
DTX may be enabled in uplink and in downlink independently of each other. DTX on or off is defined by the network
on a cell basis and can not be negotiated at call setup or during the call. The DTX scheme uses one SID frame to mark
the end of a speech burst and to start Comfort Noise Generation. It is important to note that the Comfort Noise
parameters for this start of the comfort noise generation are calculated at transmitter side from the previous eight speech
frames. A DTX hangover period needs to be applied therefore at transmitter side before sending the first SID frame.
ETSI

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3GPP TS 26.103 version 16.0.0 Release 16 11 ETSI TS 126 103 V16.0.0 (2020-11)
SID frames with incremental information for comfort noise updates are sent in speech pauses about every 480 ms,
aligned with the cell's TDMA frame structure. The defined Tandem Free Operation allows the reception of GSM EFR
DTX information for the downlink direction in all cases. The TFO respectively TrFO partner shall be prepared to
receive DTX information as well.
5.4 Five Adaptive Multi-Rate Codec Types (FR AMR, HR AMR,
UMTS AMR, UMTS AMR2, OHR AMR)
The Adaptive Multi-Rate Codec algorithm is applied in GERAN-GMSK, GERAN-8PSK and UTRAN in five different
Codec Types.
The Codec IDentification (CoID) codes are defined to be:
FR_AMR_CoID := 0x0000.0011.
HR_AMR_CoID := 0x0000.0100.
UMTS_AMR_CoID := 0x0000.0101.
UMTS_AMR_2_CoID := 0x0000.0110.
OHR_AMR_CoID := 0x0000.1011.
The AMR Codec Types can be used in conversational speech telephony services in a number of different
configurations. The set of preferred configurations is defined in TS 28.062, Table 7.11.3.1.3-2. One of these preferred
configurations, Config-NB-Code 1, is recommended for TFO-TrFO harmonisation between GSM and UMTS networks,
it is mandatory for an AoIP-supporting BSS, see 3GPP TS 48.008 [23], an AoIP-supporting BICC-based Circuit
Switched Core Network and for any SIP-I -based Circuit Switched Core Network .
The Single Codec Information Element for AMR Codec Types may have several additional parameters. These
parameters are optional in the Supported Codec List (BICC) and in the Available C
...