4. PAGE 4
4GV VAD & Classification
Voice
Activity
Detection
(VAD)
Voice
Activity
Detection
(VAD)
ClassificationClassification
Silence
Rate-1/8
Silence
Rate-1/8
Offsets
Rate-1/2
Offsets
Rate-1/2
Non-Stat
Rate-1
Non-Stat
Rate-1
Unvoiced
Rate-1/4
Unvoiced
Rate-1/4
Active
VoiceNon-Voice
Input Speech
Onsets
Rate-1
Onsets
Rate-1
VoicedVoiced
Stationary
Rate-1/4
Stationary
Rate-1/4
TransientTransient
Key contribution here
is introduction of a
new paradigm to fully
utilize rate-1/4 in
coding active speech
5. PAGE 5
Time
Silence Unvoiced Onset Voiced
RATE
1/1
1/2
1/4
1/8
4GV VAD & Classification
The proper pairing of
rate-1 and rate-1/4 that
contributes to capacity
saving in the network
7. PAGE 7
4GV-NB RL Selected Modes & Signaling Protocols
Field Length
(bits)
RATE_REDUC 3
RESERVED 3
MOBILE_TO_MOBILE 1
INIT_CODEC 1
RATE_REDUC
(binary)
(Modes)
Active Channel
(Rate ADR)
(Kbps)
‘000’ 8.30
‘001’ 7.57
‘010’ 6.64
‘011’ 6.18
‘100’ 5.82
‘101’ 5.45
‘110’ 5.08
‘111’ 4.00 (HRM)
Forward link
Dial in any Arbitrary
Capacity Operating Points (COP)
or Average Data Rate
Service Option Control Message Reverse Link
Only Eight Possible COP
8. PAGE 8
4GV-WB (RS1) Codec
8.55kbps
(Peak Rate During Active Speech)
Bandwidth
(0-4 KHz)
Bandwidth
(0-4 kHz) (4-7 kHz)
BitRates
Same Average Data Rate (ADR)
as EVRC
4GV-NB 4GV-WB
Up to 40% reduction in
Average Data Rate (ADR)
as compared with EVRC
9. PAGE 9
4GV PTT & VoIP Codecs
4GV-VoIP
4GV Core
An integrated NB/WB codec
with best utilization of QoS
attributes such as speech
time warping to complement
time varying jitter, better error
concealment to complement
High FER & Packet Losses
and adaptive De-Jitter Buffer
for a better overall perception
of voice quality over HRPD
and Packet Network
NB
WB
4GV-PTT
Integrated DTX, SID Update,
CNG and Noise Blending
with Peak/Average Data
Rate voice quality tradeoffs
& capacity assessment for
up to 6 frame bundling
13. PAGE 13
Standardization Status
• 3GPP2
4GV-NB as “EVRC-B” with SO68 well underway
– WI supported by Bell Mobility, China Unicom, KDDI, Lucent, Motorola, Nortel, Qualcomm,
SKT and Verizon
– Baseline Text was approved in Dec’05 and to be published by April’06
– Minimum Performance Specification and SW release by Jun’06
4GV-WB as “EVRC-WB” with SO70 is on-going
– Work Item supported by China Unicom, Hitachi, KDDI, Lucent, Motorola, Nortel, Qualcomm,
Samsung, SKT and Verizon
– Specification submitted in Mar’06, baseline text by May’06 and target completion by 4Q’06
• IETF
EVRC-B RTP payload format submitted as RFC3558 draft extension and new
“EVRCB” MIME-Type ( http://www.ietf.org/internet-drafts/draft-ietf-avt-compact-
bundled-evrc-02.txt )
EVRC-WB requires a new RFC3558 draft extension and new “EVRCWB” MIME-
Type
14. PAGE 14
EVRC-B Characterization Test Results
Source data from 3GPP2 C11-20060327-015, Dynastat EVRC-B Characterization Test Report
1.0
1.5
2.0
2.5
3.0
3.5
4.0
VoiceQuality(MOS)
EVRC 3.83 3.88 3.73 3.71 3.40
EVRC-B M0 3.92 3.98 3.88 3.82 3.49
EVRC-B M4 3.78 3.89 3.81 3.64 3.44
EVRC-B M6 3.68 3.68 3.69 3.70 3.45
High Input Level 0% FER 1% FER EVRC Tandem
15dB Street Noise +
1% FER
15. PAGE 15
4GV Proposed Technology Roadmap
Active Speech Average Data Rate- ADR (Kbps)
VoiceQuality(MOS)
CS 4GV-NB
EVRC
EVRC
AMR-WB12.65
PS 4GV-NB
PS 4GV-WB
CS 4GV-WB
16. PAGE 16
4GV in Summary
4GV CoreVoIP
(Both NB & WB)
Key QoS attributes
designed within the core of
codec while fully utilizing
DOrA architecture
WB-Wideband
(16kHz)
Superior wideband voice
quality with capacity
impact no worse than EVRC
NB-Narrowband
(8kHz)
Up to 40% capacity saving as
compared with EVRC while
gracefully trading voice
quality
An integrated solution based on a
common core codec with an easy
incremental software upgrade capability
that simplifies the deployment while
reducing the overall cost
