ETSI TS 126 071-2017 Digital cellular telecommunications system (Phase 2+) (GSM) Universal Mobile Telecommunications System (UMTS) LTE Mandatory speech CODEC speech processing func.pdf

1、 ETSI TS 126 071 V14.0.0 (2017-04) Digital cellular telecommunications system (Phase 2+) (GSM); Universal Mobile Telecommunications System (UMTS); LTE; Mandatory speech CODEC speech processing functions; AMR speech Codec; General description (3GPP TS 26.071 version 14.0.0 Release 14) TECHNICAL SPECI

2、FICATION ETSI ETSI TS 126 071 V14.0.0 (2017-04)13GPP TS 26.071 version 14.0.0 Release 14Reference RTS/TSGS-0426071ve00 Keywords GSM,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 Associ

3、ation but non lucratif enregistre la Sous-Prfecture de Grasse (06) N 7803/88 Important 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

4、 versions of the present document shall not be modified without the prior written 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

5、a specific network drive within ETSI Secretariat. Users of the present document should 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

6、 you find errors in the present document, please send your comment to one of the 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

7、microfilm except as authorized by written permission of ETSI. The content of the PDF version shall not be modified without the written authorization of ETSI. The copyright and the foregoing restriction extend to reproduction in all media. European Telecommunications Standards Institute 2017. All rig

8、hts reserved. DECTTM, PLUGTESTSTM, UMTSTMand the ETSI logo are Trade Marks of ETSI registered for the benefit of its Members. 3GPPTM and LTE are Trade Marks of ETSI registered for the benefit of its Members and of the 3GPP Organizational Partners. GSM and the GSM logo are Trade Marks registered and

9、owned by the GSM Association. ETSI ETSI TS 126 071 V14.0.0 (2017-04)23GPP TS 26.071 version 14.0.0 Release 14Intellectual 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 pub

10、licly 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 ETS

11、I Web server (https:/ipr.etsi.org/). 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

12、 may become, essential to the present document. Foreword This Technical Specification (TS) has been produced by ETSI 3rd Generation Partnership Project (3GPP). The present document may refer to technical specifications or reports using their 3GPP identities, UMTS identities or GSM identities. These

13、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.org/key/queryform.asp. Modal verbs terminology In the present document “shall“, “shall not“, “should“, “should not“,

14、“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). “must“ and “must not“ are NOT allowed in ETSI deliverables except when used in direct citation. ETSI ETSI TS 126 071

15、V14.0.0 (2017-04)33GPP TS 26.071 version 14.0.0 Release 14Contents Intellectual Property Rights 2g3Foreword . 2g3Modal verbs terminology 2g3Foreword . 4g31 Scope 5g32 References 5g33 Definitions and abbreviations . 6g33.1 Abbreviations . 6g34 General . 6g35 Adaptive Multi-Rate speech codec transcodi

16、ng functions . 8g36 Adaptive Multi-Rate speech codec ANSI C-code 8g37 Adaptive Multi-Rate speech codec test vectors 8g38 Adaptive Multi-Rate speech codec source controlled rate operation . 9g39 Adaptive Multi-Rate speech codec voice activity detection 9g310 Adaptive Multi-Rate speech codec comfort n

17、oise insertion . 10g311 Adaptive Multi-Rate speech codec error concealment of lost frames 10g312 Adaptive Multi-Rate speech codec frame structure . 10g313 Adaptive Multi-Rate speech codec interface to RAN 10g314 Adaptive Multi-Rate speech codec performance characterisation . 11g3Annex A (informative

18、): Change history . 12g3History 13g3ETSI ETSI TS 126 071 V14.0.0 (2017-04)43GPP TS 26.071 version 14.0.0 Release 14Foreword 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 T

19、SG 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 infor

20、mation; 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 i

21、ncorporated in the document. ETSI ETSI TS 126 071 V14.0.0 (2017-04)53GPP TS 26.071 version 14.0.0 Release 141 Scope The present document is an introduction to the speech processing parts of the narrowband telephony speech service employing the Adaptive Multi-Rate (AMR) speech coder. A general overvi

22、ew of the speech processing functions is given, with reference to the documents where each function is specified in detail. 2 References The following documents contain provisions which, through reference in this text, constitute provisions of the present document. References are either specific (id

23、entified 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 refe

24、rence implicitly refers to the latest version of that document in the same Release as the present document. 1 GSM 03.50: “Digital cellular telecommunications system (Phase 2); Transmission planning aspects of the speech service in the GSM Public Land Mobile Network (PLMN) system“. 2 3GPP TS 26.090:

25、“Transcoding functions“. 3 3GPP TS 26.073: “Adaptive Multi-Rate (AMR); ANSI C source code“. 4 3GPP TS 26.074: “Adaptive Multi-Rate (AMR); Test sequences“. 5 3GPP TS 26.093: “Source Controlled Rate operation“. 6 3GPP TS 26.094: “AMR Speech Codec; Voice Activity Detector“. 7 3GPP TS 26.092: “Mandatory

26、 Speech Codec speech processing functions; AMR Speech Codec; Comfort noise aspects“. 8 3GPP TS 26.091: “Mandatory Speech Codec speech processing functions; AMR Speech Codec; Error concealment of lost frames“. 9 3GPP TS 26.101: “Frame Structure“. 10 3GPP TS 26.102: “AMR Speech Codec; Interface to Iu

27、snd Uu“. 11 3GPP TS 26.901: “AMR wideband speech codec feasibility study report “. 12 ITU-T Recommendation G.711: “Pulse code modulation (PCM) of voice frequencies“. 13 ITU-T Recommendation H.324: “Terminal for low bit-rate multimedia communication“. ETSI ETSI TS 126 071 V14.0.0 (2017-04)63GPP TS 26

28、.071 version 14.0.0 Release 143 Definitions and abbreviations 3.1 Abbreviations For the purposes of this TS, the following abbreviations apply: ACELP Algebraic Code Excited Linear Prediction AMR Adaptive Multi-Rate BFI Bad Frame Indication CHD Channel Decoder CHE Channel EncoderGSM Global System for

29、 Mobile communications ITU-T International Telecommunication Union Telecommunication standardisation sector (former CCITT) PCM Pulse Code Modulation PLMN Public Land Mobile Network PSTN Public Switched Telephone Network RX Receive SCR Source Controlled Rate SPD SPeech Decoder SPE SPeech Encoder TC T

30、ranscoder TX TransmitUE User Equipment (terminal) 4 General The AMR speech coder consists of the multi-rate speech coder, a source controlled rate scheme including a voice activity detector and a comfort noise generation system, and an error concealment mechansim to combat the effects of transmissio

31、n errors and lost packets. The multi-rate speech coder is a single integrated speech codec with eight source rates from 4.75 kbit/s to 12.2 kbit/s, and a low rate background noise encoding mode. The speech coder is capable of switching its bit-rate every 20 ms speech frame upon command. A reference

32、configuration where the various speech processing functions are identified is given in Figure 1. In this figure, the relevant specifications for each function are also indicated. In Figure 1, the audio parts including analogue to digital and digital to analogue conversion are included, to show the c

33、omplete speech path between the audio input/output in the User Equipment (UE) and the digital interface of the network. The detailed specification of the audio parts is not within the scope of the present document. These aspects are only considered to the extent that the performance of the audio par

34、ts affect the performance of the speech transcoder. ETSI ETSI TS 126 071 V14.0.0 (2017-04)73GPP TS 26.071 version 14.0.0 Release 148bit / A-lawto13-bituniformLPF A/D12MS side onlyBSS side only GSM 06.60.AMRGSM 03.50TRANSMIT SIDESpeechEncoderComfortNoiseTXFunctionsVoiceActivityDetectorDTXControlandOp

35、eration364567GSM 06.82.AMR GSM 06.81.AMRGSM 06.60.AMRGSM 06.62.AMRSID frameSpeech frameVAD13-bituniformto8bit / A-lawLPFD/A18MS side onlyBSS side only GSM 06.60.AMRGSM 03.50RECEIVE SIDESpeechDecoderSpeechframesubstitutionDTXControlandOperation45910GSM 06.61.AMRGSM 06.81.AMRGSM 06.60.AMRGSM 06.62.AMR

36、SID frameSpeech frameComfortNoiseRXFunctions112SPflagInfo.bitsBFIInfo.bitsSIDTAFFigure 1: Overview of audio processing functions 1) 8-bit A-law or -law PCM (ITU-T Recommendation G.711 12 ), 8 000 samples/s; 2) 13-bit uniform PCM, 8 000 samples/s; 3) Voice Activity Detector (VAD) flag; 4) Encoded spe

37、ech frame, 50 frames/s, number of bits/frame depending on the AMR codec mode; 5) SIlence Descriptor (SID) frame; 6) TX_TYPE, 2 bits, indicates whether information bits are available and if they are speech or SID information; 7) Information bits delivered to the 3G AN; 8) Information bits received fr

38、om the 3G AN; 9) RX_TYPE, the type of frame received quantized into three bits. ETSI ETSI TS 126 071 V14.0.0 (2017-04)83GPP TS 26.071 version 14.0.0 Release 145 Adaptive Multi-Rate speech codec transcoding functions The adaptive multi-rate speech codec is described in 2. The technical content is ide

39、ntical to that of 3GPP TS 26.090. As shown in Figure 1, the speech encoder takes its input as a 13-bit uniform Pulse Code Modulated (PCM) signal either from the audio part of the UE or on the network side, from the Public Switched Telephone Network (PSTN) via an 8-bit A-law or -law to 13-bit uniform

40、 PCM conversion. The encoded speech at the output of the speech encoder is packetized and delivered to the network interface. In the receive direction, the inverse operations take place. The detailed mapping between input blocks of 160 speech samples in 13-bit uniform PCM format to encoded blocks (i

41、n which the number of bits depends on the presently used codec mode) and from these to output blocks of 160 reconstructed speech samples is described in 2. The coding scheme is Multi-Rate Algebraic Code Excited Linear Prediction. The bit-rates of the source codec are listed in Table 1. An AMR speech

42、 codec capable UE shall support all source rates listed in Table 1. Table 1: Source codec bit-rates for the AMR codec. Codec mode Source codec bit-rate AMR_12.20 12,20 kbit/s (GSM EFR) AMR_10.20 10,20 kbit/sAMR_7.95 7,95 kbit/sAMR_7.40 7,40 kbit/s (IS-641) AMR_6.70 6,70 kbit/s (PDC-EFR) AMR_5.90 5,9

43、0 kbit/sAMR_5.15 5,15 kbit/sAMR_4.75 4,75 kbit/s AMR_SID 1,80 kbit/s (see note 1) NOTE 1: Assuming SID frames are continously transmitted NOTE 2: GSM-EFR is the 3GPP TS 26.090 Enhanced Full Rate Speech Codec (also identical to the TIA TDMA-US1 Enhanced speech codec) NOTE 3: IS-641is the TIA/EIA IS-6

44、41 TDMA Enhanced Full Rate Speech Codec NOTE 4: PDC-EFR is the ARIB 6.7 kbit/s Enhanced Full Rate Speech Codec 6 Adaptive Multi-Rate speech codec ANSI C-code The ANSI-C code of the speech codec, VAD and CNG system are described in 3. The ANSI C-code is mandatory. The ANSI C-code is identical to that

45、 of 3GPP TS 26.073 3. 7 Adaptive Multi-Rate speech codec test vectors A set of digital test sequences is specified in 4, thus enabling the verification of compliance, i.e. bit-exactness, to a high degree of confidence. The test vectors are identical to those of 3GPP TS 26.074 4. The test sequences a

46、re defined separately for: The speech codec described in 2, The VAD described in 6, The CN generation described in 7. The adaptive multi-rate speech transcoder, VAD, SCR system and comfort noise parts of the audio processing functions (see Figure 1) are defined in bit exact arithmetic. Consequently,

47、 they shall react on a given input sequence always with ETSI ETSI TS 126 071 V14.0.0 (2017-04)93GPP TS 26.071 version 14.0.0 Release 14the corresponding bit exact output sequence, provided that the internal state variables are also always exactly in the same state at the beginning of the test. The i

48、nput test sequences provided shall force the corresponding output test sequences, provided that the tested modules are in their home-state when starting. The modules may be set into their home states by provoking the appropriate homing-functions. NOTE: This is normally done during reset (initialisat

49、ion of the codec). Special inband signalling frames (encoder-homing-frame and decoder-homing-frame) described in 2have been defined to provoke these homing-functions also in remotely placed modules. At the end of the first received homing frame, the audio functions that are defined in a bit exact way shall go into their predefined home states. The output corresponding to the first homing frame is dependent on the codec state when the frame was received. Any consecutive homing frames shall produce corresponding ho