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TS 126 090 V3.1.0 (2000-01) Technical Specification

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TS 126 090 V3.1.0 (2000-01) Technical Specification ETSI TS 126 090 V3.1.0 (2000-01) Technical Specification Universal Mobile Telecommunications System (UMTS); Mandatory Speech Codec speech processing functions AMR speech codec; Transcoding functions (3G TS 26.090 version 3.1.0 Release 1999) (3G TS 26.090 version 3.1.0 Release 1999) Page 1 ETSI TS 126 090 V3.1.0 (2000-01) Reference DTS/TSGS-0426090U Keywords UMTS ETSI Postal address F-06921 Sophia Antipolis Cedex - FRANCE Office address 650 Route des Lucioles - Sophia Antipolis Valbonne - FRANCE Tel.:+33492944200 Fax:+33493654716 Siret N° 348 623 562 00017 - NAF 742 C Association à but non lucratif enregistrée à la Sous-Préfecture de Grasse (06) N° 7803/88 Internet [email protected] Individual copies of this ETSI deliverable can be downloaded from http://www.etsi.org If you find errors in the present document, send your comment to: [email protected] Important notice This ETSI deliverable may be made available in more than one electronic version or in print. In any case of existing or perceived difference in contents between such versions, the reference version is the Portable Document Format (PDF). In case of dispute, the reference shall be the printing on ETSI printers of the PDF version kept on a specific network drive within ETSI Secretariat. Copyright Notification No part may be reproduced except as authorized by written permission. The copyright and the foregoing restriction extend to reproduction in all media. © European Telecommunications Standards Institute 2000. All rights reserved. ETSI (3G TS 26.090 version 3.1.0 Release 1999) Page 2 ETSI TS 126 090 V3.1.0 (2000-01) 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 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 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 Technical Specification (TS) has been produced by the ETSI 3rd Generation Partnership Project (3GPP). The present document may refer to technical specifications or reports using their 3GPP identities or GSM identities. These should be interpreted as being references to the corresponding ETSI deliverables. The mapping of document identities is as follows: For 3GPP documents: 3G TS | TR nn.nnn "<title>" (with or without the prefix 3G) is equivalent to ETSI TS | TR 1nn nnn "[Digital cellular telecommunications system (Phase 2+) (GSM);] Universal Mobile Telecommunications System; <title> For GSM document identities of type "GSM xx.yy", e.g. GSM 01.04, the corresponding ETSI document identity may be found in the Cross Reference List on www.etsi.org/key ETSI Page 3 TS 26.090 : December 1999 Contents Foreword............................................................................................................................................................ 5 1 Scope ....................................................................................................................................................... 6 2 Normative references............................................................................................................................... 6 3 Definitions, symbols and abbreviations................................................................................................... 7 3.1 Definitions..........................................................................................................................................................7 3.2 Symbols..............................................................................................................................................................8 3.3 Abbreviations ...................................................................................................................................................14 4 Outline description ................................................................................................................................ 14 4.1 Functional description of audio parts ...............................................................................................................14 4.2 Preparation of speech samples..........................................................................................................................15 4.2.1 PCM format conversion..............................................................................................................................15 4.3 Principles of the adaptive multi-rate speech encoder .......................................................................................16 4.4 Principles of the adaptive multi-rate speech decoder .......................................................................................18 4.5 Sequence and subjective importance of encoded parameters ...........................................................................19 5 Functional description of the encoder ................................................................................................... 19 5.1 Pre-processing (all modes) ...............................................................................................................................19 5.2 Linear prediction analysis and quantization .....................................................................................................19 12.2 kbit/s mode 19 10.2, 7.95, 7.40, 6.70, 5.90, 5.15, 4.75 kbit/s modes.........................................................................................................19 5.2.1 Windowing and auto-correlation computation............................................................................................20 12.2 kbit/s mode 20 10.2, 7.95, 7.40, 6.70, 5.90, 5.15, 4.75 kbit/s modes.........................................................................................................21 5.2.2 Levinson-Durbin algorithm (all modes)......................................................................................................21 5.2.3 LP to LSP conversion (all modes) ..............................................................................................................22 5.2.4 LSP to LP conversion (all modes) ..............................................................................................................23 5.2.5 Quantization of the LSP coefficients ..........................................................................................................24 12.2 kbit/s mode 24 10.2, 7.95, 7.40, 6.70, 5.90, 5.15, 4.75 kbit/s modes ........................................................................................................25 5.2.6 Interpolation of the LSPs ............................................................................................................................25 12.2 kbit/s mode 25 10.2, 7.95, 7.40, 6.70, 5.90, 5.15, 4.75 kbit/s modes ........................................................................................................26 5.2.7 Monitoring resonance in the LPC spectrum (all modes).............................................................................26 5.3 Open-loop pitch analysis ..................................................................................................................................27 12.2 kbit/s mode 27 10.2 kbit/s mode 28 7.95, 7.40, 6.70, 5.90 kbit/s modes....................................................................................................................................29 5.15, 4.75 kbit/s modes......................................................................................................................................................29 5.4 Impulse response computation (all modes) ......................................................................................................30 5.5 Target signal computation (all modes) .............................................................................................................30 5.6 Adaptive codebook...........................................................................................................................................31 5.6.1 Adaptive codebook search ..........................................................................................................................31 12.2 kbit/s mode 31 7.95 kbit/s mode 32 10.2, 7.40 kbit/s mode .......................................................................................................................................................33 6.70, 5.90 kbit/s modes......................................................................................................................................................33 5.15, 4.75 kbit/s modes......................................................................................................................................................34 5.6.2 Adaptive codebook gain control (all modes)............................................................................................................35 5.7 Algebraic codebook..........................................................................................................................................35
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