1、 ETSI TS 126 450 V15.0.0 (2018-07) Universal Mobile Telecommunications System (UMTS); LTE; Codec for Enhanced Voice Services (EVS); Discontinuous Transmission (DTX) (3GPP TS 26.450 version 15.0.0 Release 15) TECHNICAL SPECIFICATION ETSI ETSI TS 126 450 V15.0.0 (2018-07)13GPP TS 26.450 version 15.0.0
2、 Release 15Reference RTS/TSGS-0426450vf00 Keywords LTE,UMTS ETSI 650 Route des Lucioles F-06921 Sophia Antipolis Cedex - FRANCE Tel.: +33 4 92 94 42 00 Fax: +33 4 93 65 47 16 Siret N 348 623 562 00017 - NAF 742 C Association but non lucratif enregistre la Sous-Prfecture de Grasse (06) N 7803/88 Impo
3、rtant notice The present document can be downloaded from: http:/www.etsi.org/standards-search The present document may be made available in electronic versions and/or in print. The content of any electronic and/or print versions of the present document shall not be modified without the prior written
4、 authorization of ETSI. In case of any existing or perceived difference in contents between such versions and/or in print, the only prevailing document is the print of the Portable Document Format (PDF) version kept on a specific network drive within ETSI Secretariat. Users of the present document s
5、hould be aware that the document may be subject to revision or change of status. Information on the current status of this and other ETSI documents is available at https:/portal.etsi.org/TB/ETSIDeliverableStatus.aspx If you find errors in the present document, please send your comment to one of the
6、following services: https:/portal.etsi.org/People/CommiteeSupportStaff.aspx Copyright Notification No part may be reproduced or utilized in any form or by any means, electronic or mechanical, including photocopying and microfilm except as authorized by written permission of ETSI. The content of the
7、PDF version shall not be modified without the written authorization of ETSI. The copyright and the foregoing restriction extend to reproduction in all media. ETSI 2018. All rights reserved. DECTTM, PLUGTESTSTM, UMTSTMand the ETSI logo are trademarks of ETSI registered for the benefit of its Members.
8、 3GPPTM and LTETMare trademarks of ETSI registered for the benefit of its Members and of the 3GPP Organizational Partners. oneM2M logo is protected for the benefit of its Members. GSMand the GSM logo are trademarks registered and owned by the GSM Association. ETSI ETSI TS 126 450 V15.0.0 (2018-07)23
9、GPP TS 26.450 version 15.0.0 Release 15Intellectual Property Rights Essential patents IPRs essential or potentially essential to normative deliverables may have been declared to ETSI. The information pertaining to these essential IPRs, if any, is publicly available for ETSI members and non-members,
10、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 (https:/ipr.etsi.org/). Pursuant to t
11、he 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. Tr
12、ademarks The present document may include trademarks and/or tradenames which are asserted and/or registered by their owners. ETSI claims no ownership of these except for any which are indicated as being the property of ETSI, and conveys no right to use or reproduce any trademark and/or tradename. Me
13、ntion of those trademarks in the present document does not constitute an endorsement by ETSI of products, services or organizations associated with those trademarks. Foreword This Technical Specification (TS) has been produced by ETSI 3rd Generation Partnership Project (3GPP). The present document m
14、ay refer to technical specifications or reports using their 3GPP identities, UMTS identities or GSM identities. These should be interpreted as being references to the corresponding ETSI deliverables. The cross reference between GSM, UMTS, 3GPP and ETSI identities can be found under http:/webapp.etsi
15、.org/key/queryform.asp. Modal verbs terminology In the present document “shall“, “shall not“, “should“, “should not“, “may“, “need not“, “will“, “will not“, “can“ and “cannot“ are to be interpreted as described in clause 3.2 of the ETSI Drafting Rules (Verbal forms for the expression of provisions).
16、 “must“ and “must not“ are NOT allowed in ETSI deliverables except when used in direct citation. ETSI ETSI TS 126 450 V15.0.0 (2018-07)33GPP TS 26.450 version 15.0.0 Release 15Contents Intellectual Property Rights 2g3Foreword . 2g3Modal verbs terminology 2g3Foreword . 4g31 Scope 5g32 References 5g33
17、 Abbreviations . 5g34 General . 6g34.1 Background 6g34.2 General organization 6g35 EVS Codec DTX Operation . 7g35.1 Transmit (TX) side . 7g35.2 Receive (RX) side 7g3Annex A (informative): Change history . 8g3History 9g3ETSI ETSI TS 126 450 V15.0.0 (2018-07)43GPP TS 26.450 version 15.0.0 Release 15Fo
18、reword This Technical Specification has been produced by the 3rdGeneration 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
19、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 sec
20、ond 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 ETSI TS 126 450 V15.0.0 (2018-07)53GPP TS 26.450 version 15.0.0 Release 151 Scope T
21、his document specifies the system level aspects of the Discontinuous Transmission (DTX) function of the EVS codec. 2 References The following documents contain provisions which, through reference in this text, constitute provisions of the present document. - References are either specific (identifie
22、d 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 referen
23、ce implicitly refers to the latest version of that document in the same Release as the present document. 1 3GPP TR 21.905: “Vocabulary for 3GPP Specifications“. 2 3GPP TS 26.445: “Codec for Enhanced Voice Services (EVS); Detailed Algorithmic Description “. 3 3GPP TS 26.442: “ Codec for Enhanced Voic
24、e Services (EVS); ANSI C code (fixed-point)“. 4 3GPP TS 26.443: “ Codec for Enhanced Voice Services (EVS); ANSI C code (floating-point)“. 5 3GPP TS 26.444: “ Codec for Enhanced Voice Services (EVS); Test Sequences“. 6 3GPP TS 26.446: “ Codec for Enhanced Voice Services (EVS); AMR-WB Backward Compati
25、ble Functions“. 7 3GPP TS 26.447: “ Codec for Enhanced Voice Services (EVS); Error Concealment of Lost Packets“. 8 3GPP TS 26.448: “ Codec for Enhanced Voice Services (EVS); Jitter Buffer Management“. 9 3GPP TS 26.449: “ Codec for Enhanced Voice Services (EVS); Comfort Noise Generation (CNG) Aspects
26、“. 10 3GPP TS 26.441: “ Codec for Enhanced Voice Services (EVS); General Overview“. 11 3GPP TS 26.451: “ Codec for Enhanced Voice Services (EVS); Voice Activity Detection (VAD)“. 12 3GPP TS 26.114: “Multimedia Telephony; Media handling and interaction“. 13 3GPP TS 26.131: “Terminal acoustic characte
27、ristics for telephony; Requirements “. 14 3GPP TR 26.952: “Codec for Enhanced Voice Services (EVS); Performance Characterization“. 3 Abbreviations For the purposes of the present document, the abbreviations given in TR 21.905 1 and the following apply. An abbreviation defined in the present document
28、 takes precedence over the definition of the same abbreviation, if any, in TR 21.905 1. ACELP Algebraic Code-Excited Linear Prediction AMR-WB Adaptive Multi Rate Wideband (codec) CNG Comfort Noise Generator DTX Discontinuous Transmission EVS Enhanced Voice Services ETSI ETSI TS 126 450 V15.0.0 (2018
29、-07)63GPP TS 26.450 version 15.0.0 Release 15FB Fullband FEC Frame Erasure Concealment IP Internet Protocol JBM Jitter Buffer Management MSB Most Significant Bit MTSI Multimedia Telephony Service for IMS NB Narrowband PS Packet SwitchedPSTN Public Switched Telephone Network SAD Signal Activity Detec
30、tion SC-VBR Source Controlled - Variable Bit Rate SID Silence Insertion Descriptor SWB Super Wideband VAD Voice Activity Detection WB Wideband WMOPS Weighted Millions of Operations Per Second 4 General 4.1 Background The present document specifies the system level aspects of the Discontinuous Transm
31、ission (DTX) function of the EVS codec. Specific codec functions that implement the DTX functionality are described in TS 26.445 2. Discontinuous transmission (DTX) is a mechanism for the EVS Codec to encode the input signal at a lower average rate by taking speech inactivity into account. The DTX s
32、cheme is useful for the following purposes: - to conserve UE power, - to improve network capacity. DTX in the transmitting path (uplink) shall be in operation in UEs if commanded so by the network. The UE shall handle DTX in the receiving path (downlink) at any time, regardless of whether DTX in the
33、 transmitting path is commanded or not. 4.2 General organization The default DTX mechanism described in the present document requires the following functions: - a Signal Activity Detector (SAD) on the transmit (TX) side; - evaluation of the background acoustic noise on the transmit (TX) side in orde
34、r to transmit characteristic parameters to the receive (RX) side; - generation, on the receive (RX) side, of a similar noise called comfort noise during periods where the transmission is switched off. The Signal Activity Detector (SAD) is defined in TS 26.451 11 and the comfort noise functions in TS
35、 26.449 9. Both are based partly on the EVS Codec and its internal variables defined in TS 26.445 2. In addition to these functions, if the parameters arriving at the RX side are detected to be seriously corrupted by errors, the speech or comfort noise shall be generated from substituted data in ord
36、er to avoid seriously annoying effects for the listener. These functions are defined in TS 26.447 7. An overall description of the speech processing parts can be found in TS 26.441 10. An overview of the DTX operation is shown in Figure 1. ETSI ETSI TS 126 450 V15.0.0 (2018-07)73GPP TS 26.450 versio
37、n 15.0.0 Release 15Figure 1: Block diagram of DTX Operation 5 EVS Codec DTX Operation 5.1 Transmit (TX) side There are two algorithms for extending the DTX hangover period. One is a general hangover algorithm and other is specific to music. Both are defined in clause 5.1.12.5 of TS 26.445 2. The mai
38、n specification of the DTX/CNG algorithms is contained in clause 5.6 of TS 26.445 2. The bit allocation of SID frames generated for DTX operation is defined in clause 7.2 of TS 26.445 2. 5.2 Receive (RX) side Operation of the EVS decoder, including decoding of SID frames generated during DTX operati
39、on is described in clause 6.7 of TS 26.445 2. ETSI ETSI TS 126 450 V15.0.0 (2018-07)83GPP TS 26.450 version 15.0.0 Release 15Annex A (informative): Change history Change history Date TSG # TSG Doc. CR Rev Subject/Comment Old New 2014-09 65 SP-140465 Presented at TSG#65 for approval 1.0.0 2014-09 65
40、Approved at TSG SA#65 1.0.0 12.0.0 2015-12 70 Version for Release 13 12.0.0 13.0.0 Change history Date Meeting TDoc CR Rev Cat Subject/Comment New version 2017-03 75 Version for Release 14 14.0.0 2018-06 80 Version for Release 15 15.0.0 ETSI ETSI TS 126 450 V15.0.0 (2018-07)93GPP TS 26.450 version 15.0.0 Release 15History Document history V15.0.0 July 2018 Publication
