Wideband Codec

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    1 NOKIA 2002 3GPP2 Wideband Codec Presentation

    W-VRM: Wideband Variable-RateMulti-Mode Speech Codec for 3GPP2

    Mitch Tseng, Ph.D.Nokia

    January 21, 2002

    3GPP2 TSG-S (Seoul, Korea) S00-20020121-006

    Copyright 3GPP2 2002

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    2 NOKIA 2002 3GPP2 Wideband Codec Presentation

    Topics

    Wideband Speech Background

    Codec Evolution

    AMR-WB: Wideband Speech in 3GPP & ITU

    W-VRM: Wideband Speech in 3GPP2 Audio Demonstration

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    3 NOKIA 2002 3GPP2 Wideband Codec Presentation

    WIDEBAND SPEECH:

    BACKGROUND MATERIAL

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    4 NOKIA 2002 3GPP2 Wideband Codec Presentation

    WHAT IS WIDEBAND SPEECH?

    The status quo narrowband speech codecs including PCMprovide a voice bandwidth of 300 Hz~3.4 kHz.

    A wideband codec operates at a 16 kHz sampling rate and

    provides a voice bandwidth of 50 Hz~7 kHz.

    More bandwidth, both at the upper end and the lower end.

    7 kHz3.4 kHz

    Status Quo (PCM) Wideband

    50 Hz 300 Hz

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    5 NOKIA 2002 3GPP2 Wideband Codec Presentation

    WHY WIDEBAND SPEECH?

    Current mobile systems and fixed line telephone networks offeronly narrowband speech services (~300-3400 Hz)

    Recent advances in speech coding have made wideband codingfeasible in bit-rates applicable to mobile systems

    Wideband provides superior quality over narrowband telephony

    Increased naturalness (lowend)

    Better fricativedifferentiation (high end)-> higher intelligibility

    Increased presence-> feeling of transparentcommunication

    Increased comfort

    Easier speaker recognition

    NarrowbandSpeech

    300-3400Hz

    Wideban

    dSpeech

    50-70

    00Hz

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    6 NOKIA 2002 3GPP2 Wideband Codec Presentation

    DEMONSTRATION: NARROWBANDVS WIDEBAND SPEECH

    Experiencingthe Paradigm Shift

    in End-to-End Voice Quality

    300 Hz - 3.4 kHz

    50 Hz - 7 kHzVoice Quality

    NarrowbandMale

    Speech

    NarrowbandFemaleSpeech

    WidebandFemaleSpeech

    WidebandMale

    Speech

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    7 NOKIA 2002 3GPP2 Wideband Codec Presentation

    WHY WIDEBAND SPEECH NOW? Competitive Issues

    A voice quality that is superior to the status quo and will sell in thefuture

    All narrowband codecs today provide near-landline quality

    (Squeezing the limit of PCM) Wideband codec voice quality far exceeds landline quality Challenge from Voice over IP

    Worldwide Wideband Codec Efforts ITU G.722 for Multimedia Applications

    3GPP Wideband AMR, multi-rate, each rate fixed with VAD/DTX

    ITU-G.722.1: ITU Wideband Codec for Voice and Multimedia 3GPP AMR-WB = ITU-G.722.2

    Our Objective To standardize a Multi-mode, Variable Rate Bandwidth-Efficient

    Wideband Codec that fits in the CDMA2000 Rate Set 2

    environment and can interoperate with other Wideband Codecs

    ITU, 3GPP

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    8 NOKIA 2002 3GPP2 Wideband Codec Presentation

    WIRELESS SPEECH CODEC

    EVOLUTION WITH A LOOK AT THEFUTURE

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    9 NOKIA 2002 3GPP2 Wideband Codec Presentation

    ?

    EVOLUTION OF WIRELESS SPEECHCODECS

    IS-96A

    Rate-Set I

    1993 FR

    13 kbps

    1989

    3GPP2:Variable RateSpeech Coding

    3GPP:Fixed RateSpeech CodingWith VAD/DTX

    QCELP13Rate-Set II

    1994

    EVRC

    Rate-Set I

    1995

    SMVMultimodeRate-Set I

    2001

    HR

    5.6 kbps

    1995

    EFR

    12.2 kbps1996

    AMR-NB

    Multi-Rate

    1999

    3GPP/ITUAMR-WBMulti-Rate

    2000-2001

    W-VMRRate-Set II

    Common Mode

    Of Operation(Interoperable Mode)

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    10 NOKIA 2002 3GPP2 Wideband Codec Presentation

    STATE-OF-THE-ART:VARIABLE RATE MULTI-MODE CODING

    Increasing Average Data Rate

    IncreasingVoiceQuality

    Mode 2

    Mode 1

    SMV

    Mode 0

    EVRC

    Quality/data rate curves

    Narrowband Codecs

    Mode 3

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    11 NOKIA 2002 3GPP2 Wideband Codec Presentation

    VARIABLE RATE MULTI-MODEWIDEBAND SPEECH CODING

    Increasing Average Data Rate

    IncreasingVoiceQuality Mode 3

    Mode 2

    Wideband Codec

    Mode 0

    Quality/data rate curve

    Mode 1

    Rate Set 2Upper Limit

    QCELP13

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    12 NOKIA 2002 3GPP2 Wideband Codec Presentation

    3GPP2 CODECS: QUALITY AND CAPACITY

    Increasing ADR

    IncreasingVoice

    Quality

    QCELP13

    SMVMode 0

    EVRCSMV

    Mode 3

    SMVMode 2

    SMVMode 1

    Rate-Set IIRate-Set I

    W-VRM

    Mode 2W-VRMMode 3

    W-VRMMode 1

    W-VRMMode 0

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    13 NOKIA 2002 3GPP2 Wideband Codec Presentation

    AMR-WB: WIDEBAND SPEECH

    FOR 3GPP AND ITU

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    14 NOKIA 2002 3GPP2 Wideband Codec Presentation

    THE AMR WIDEBAND CODECSTANDARD

    3GPP approved the Adaptive Multi Rate WideBand(AMR-WB) codec standard in March 2001

    In July 2001 AMR-WB was adopted as the new ITU-Twideband standard

    First codec to be used both for wireless and wirelineservices: No transcoding between wireless and wirelinesystems

    -> no loss of quality in the interconnection Simplifies the implementation of global wideband

    speech services

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    15 NOKIA 2002 3GPP2 Wideband Codec Presentation

    W-VRM: WIDEBAND VARIABLE-RATEMULTI-MODE SPEECH CODEC FOR

    3GPP2

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    16 NOKIA 2002 3GPP2 Wideband Codec Presentation

    W-VRM FOR 3GPP2: OVERVIEW

    Proposed Codec is Ideal for 3GPP2 Applications: Less Complex than SMV (Lower Complexity and Lower Memory)

    Same Algorithmic Delay as SMV with 20ms frame structure

    Multi-mode, Variable Rate Codec functionally similar to SMV

    Variable Rate to Provide Better Bandwidth Efficiency

    Comparable Voice Quality with ITU/3GPP Wideband Codec

    Provides Superb End-to-End Voice Quality at Rate Set2 and at QCELP13 Capacity

    Suitable for 3GPP2 TFO and VoIP Applications

    Interoperable with new ITU/3GPP Wideband Codec A Multi-mode Codec Functionally Similar to SMV

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    17 NOKIA 2002 3GPP2 Wideband Codec Presentation

    W-VRM: PROPOSED REQUIREMENTS

    Input sampling rate @ 16 kHz and audio bandwidth 50-7000 Hz

    Frame size 20 ms

    Multi-mode and variable-rate wideband coding system

    Full compliance with IS-95/cdma2000 rate-set II in allmodes

    No physical layer changes required.

    Four modes of operation Mode 0: Worldwide Interoperable Mode Mode 1: Premium mode (Quality)

    Mode 2: Standard mode (IS-733 ADR equivalence) Mode 3: Economy mode (Capacity)

    Algorithmic delay less than 35 ms

    Computational complexity less than SMV

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    18 NOKIA 2002 3GPP2 Wideband Codec Presentation

    W-VRM Interoperable Mode

    Mode 0(12.65kbps) Mode 0(12.65kbps)

    WB-AMR@12.65kbps

    WB-AMR@12.65kbps

    OthersOthers

    OtherModes

    OtherModes

    WB-VRMWB-VRM

    WB-AMRWB-AMR

    WCDMA

    CDMA2000

    Interoperable

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    19 NOKIA 2002 3GPP2 Wideband Codec Presentation

    W-VRM Standardization

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    20 NOKIA 2002 3GPP2 Wideband Codec Presentation

    W-VRM: APPLICATIONS

    Tandem-Free Mobile-to-Mobile callsWideband speech codec can be used for transparent-networkmobile-to-mobile calls.

    Wideband telephony over packet networks (Mobile-to-IP)The intrinsic bandlimited nature of the current PSTN and wireless

    systems can be overcome through the use of IP networks. Teleconferencing

    Wideband coding can further improve the quality of service forwireless/wireline teleconferencing systems beyond of what can be

    achieved through the use of narrowband codecs.

    Wireless MultimediaThere are a multitude of wireless multimedia applications such asstreaming and broadcasting that can benefit from the advantagesoffered by wideband speech coding.

    Rate Set 2, Tandem Free and IP are the Keys

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    21 NOKIA 2002 3GPP2 Wideband Codec Presentation

    W-VRM: STANDARDIZATION ASPECTSProposed Schedule

    1Q 2002: Approval of the work item. Definition of thehigh-level requirements.

    2Q 2002: Final definition of the requirements and

    approval of the test plan for the wideband speech codec. 3Q 2002: Characterization and standardization of the

    wideband codec and completion of the baselinespecifications.

    Recommend TSG-S to approve the work item and Stage 1so that the Voice Services group (TSG-C WG1 SWG1) canstart the work ASAP.

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    22 NOKIA 2002 3GPP2 Wideband Codec Presentation

    SUMMARY 3GPP and ITU Have Standardized a Common

    Wideband Speech Codec wireless and wireline applications easily the best as the competition proved

    3GPP2 Has the Opportunity to Harmonize Via

    Our Own Wideband Speech Codec with aCommon Mode of Operation AMR-WB 12.65 mode = W-VRM Mode 0 other modes use varia

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