voice quality improvement

1. www.huawei.com
Security Level:
HUAWEI TECHNOLOGIES CO., LTD.
Top-quality Voice Radar Network
Insight Report

2. HUAWEI TECHNOLOGIES CO., LTD. Huawei Confidential 2
All the 4 aspects influence and help each other
• Access is the foundation of Voice
• Completion and Quality are closely related to each other.
• Quality represents overall voice quality.
• Abnormal voice indicates the probability of serious bad quality for user
Voice Radar: multidimensional and effective to Evaluate Voice Quality
Four aspect for Voice model
Quality/
abnormal
Completion
Access
Voice Radar Guarantee KPI and KQI
Quickly Call out without missing call
Call stable
Sound Clear
Total Score:
counter1*weight1+ counter2*weight2+…+counteri*weighti
RADAR 10 9 8 7 6 5 4 3 2 1
Accessibility(%) >=99.90 >=99.80 >=99.70 >=99.60 >=99.50 >=99.35 >=99.20 >=99.0 >=98.0 <98.0
Take the access radar as an example:
Radar counter is to be calculated as the average for the complete previous week, Value to be mapped into the Radar scale (0 to 10) is the average over the
Cluster or RNC
0
1
2
3
4
5
6
7
8
9
10
Accessibility
Delay
Retainability
Uplink EVQI
Downlink EVQI
UL EVQI
DL UL EVQI
Silent Ratio
Garbled Voice Ratio
Voice Quality
Abnormal Access
Completion

3. HUAWEI TECHNOLOGIES CO., LTD. Huawei Confidential 3
Radar Score Range Best Value Weight Formula
Accessibility 0~10 100% 15% (CS RRC and Cellupdate SR) * CS RAB SR
Delay 0~10 3s 10% EstabMeanTime of OrigCall AMR
Retainability 0~10 0 15% CS CDR
Ratio of uplink EVQI lower
than 3
0~10 0% 10% (EVQI.UL.Bad.Num+EVQI.UL.Poor.Num)/Total UL EVQI
Ratio of downlink EVQI
lower than 3
0~10 0% 10% (EVQI.DL.Bad.Num+EVQI.DL.Poor.Num)/Total DL EVQI
UL EVQI 0~10 5 10%
(VS.EVQI.AMRWB.UL.TotalValue+VS.EVQI.AMRNB.UL.TotalValue)
/(Total UL NB EVQI Num + Total UL WB EVQI Num ) /100
DL EVQI 0~10 5 10%
(VS.EVQI.AMRWB.DL.TotalValue+VS.EVQI.AMRNB.DL.TotalValue)
/(Total DL NB EVQI Num + Total DL WB EVQI Num ) /100
Silent Ratio 0~10 0% 10% (VS.AMRNB.ULSilent.OccurNum+VS.AMRWB.ULSilent.OccurNum)/RAB Num
Garbled Voice Ratio 0~10 0% 10% (ULGarbledVoice.OccurNum)/RAB Num
Voice Radar: Definition、Formula and Weight

4. HUAWEI TECHNOLOGIES CO., LTD. Huawei Confidential 4
Top-Quality Voice Radar Score Standard
The Radar Scoring Standard is formulated based on the big data analysis of global sites.
Level Excellent Good Accept Bad
RADAR 10 9 8 7 6 5 4 3 2 1
VOICE CSSR(%) >=99.90 >=99.80 >=99.70 >=99.60 >=99.50 >=99.35 >=99.20 >=99.0 >=98.0 <98.0
VOICE Delay(s) <=4.1 <=4.5 <=5.0 <=5.4 <=5.8 <=6.2 <=6.6 <=7.0 <=8.0 >8.0
VOICE CDR(%) <=0.08 <=0.12 <=0.15 <=0.20 <=0.25 <=0.30 <=0.40 <=0.60 <=1.0 >1.00
UL EVQI<3(%) <=5.00 <=8.00 <=12.00 <=16.0 <=20.0 <=25.0 <=30.0 <=40.0 <=50.0 >50.0
DL EVQI<3(%) <=5.00 <=8.00 <=12.00 <=16.0 <=20.0 <=25.0 <=30.0 <=40.0 <=50.0 >50.0
Average UL EVQI >=3.48 >=3.42 >=3.37 >=3.32 >=3.27 >=3.22 >=3.16 >=3.10 >=3.00 <3.00
Average DL EVQI >=3.48 >=3.42 >=3.37 >=3.32 >=3.27 >=3.22 >=3.16 >=3.10 >=3.00 <3.00
Silent Ratio(%) <=0.05 <=0.08 <=0.11 <=0.14 <=0.17 <=0.21 <=0.25 <=0.40 <=0.65 >0.65
Garbled Voice Ratio(%) <=0.01 <=0.02 <=0.03 <=0.04 <=0.05 <=0.06 <=0.08 <=0.50 <=1.0 >1.0

5. HUAWEI TECHNOLOGIES CO., LTD. Huawei Confidential 5
Top-Quality Voice Radar Score Result
Radar Name Value Original Score Weight Final Score
Voice CSSR(%)
Voice Delay(s)
Voice CDR(%)
UL EVQI<3(%)
DL EVQI<3(%)
UL EVQI
DL EVQI
Silent Ratio(%)
Voice Garbled
Ratio(%)
Total Score

6. HUAWEI TECHNOLOGIES CO., LTD. Huawei Confidential 6
Top-Quality Voice Analysis Result
Cause Detail Cause Ratio Solution
UE Part UE Problem NA
RNC Above CN or IU transmission Problem CN or IU transmission Check
RNC Inner DSP overload DSP expansion
IUB IUB transmission limit
check IUB transmission based on the Cell
IDs
RF
ECNO limit(<-16dB)
1. Increase user downlink TX power
2. increasing Active set number
3. solve RF problem
RSCP limit(<-105dBm)
1. Increase user downlink TX power
2. increasing Active set number
3. solve RF problem
RTWP limit(>-95dBm)
1. Increase user uplink TX power
2. constriction for BLER
3. PLVA
4. CS precise power control
5. crystal voice
6. RTWP Check and Optimization
In compress mode
1. set proper 2d、2f threshold
2. Compress mode Timer Optimization
TX power limited
1. Add user uplink TX power
2. increasing Active set number
3. PLVA
4. crystal voice
PSC conflict PSC conflict check and optimization
Missing Neighbor Missing Neighbor check and optimization
Other Other further analysis

7. HUAWEI TECHNOLOGIES CO., LTD. Huawei Confidential 7
 Total Radar Score result:
 Voice quality root cause: main issue is RF(EcNO, RSCP, RTWP), ratio
Wireless
Parameter
Optimization
HD Voice
Feature
Optimization
Network
Basic
Optimization
Solution Overview for Top-Quality Voice
Parameter Feature RF
Solution 0%
0%

8. HUAWEI TECHNOLOGIES CO., LTD. Huawei Confidential 8
Solution Name NE
Parameter
OK NOK
Parameter
Current
Value
Suggested Value MML Priority
Increase user
downlink TX
power
CELL
RLMAXDLPWR(MAXBITRATE=12200) //Add downlink power
MOD UCELLRLPWR: CellId=XX, CNDomainId=CS_DOMAIN,
MaxBitRate=12200,RlMaxDlPwr=30, RlMinDlPwr=-120;
//maintain the 3.4k txpower as before. the example is
ADD UCELLRLPWR: CellId=XX,
CNDOMAINID=CS_DOMAIN,MAXBITRATE=3400,RLMAXDLPW
R=0, RLMINDLPWR=-150, DLSF=D256;
H(in non
TCP
overload
cells)
RLMINDLPWR(MAXBITRATE=12200)
RLMAXDLPWR(MAXBITRATE=3400)
RLMINDLPWR(MAXBITRATE=3400)
Constriction for
UL BLER
RNC
BLERQUALITY
//For AMR-NB
MOD UTYPRABOLPC:RABINDEX=0, SUBFLOWINDEX=0,
TRCHTYPE=TRCH_DCH, DELAYCLASS=1, BLERQUALITY=-27，
MAXSIRSTEPUP=1500, SIRADJUSTSTEP=3,
INITSIRTARGET=112, MAXSIRTARGET=152, MINSIRTARGET=82;
//For AMR-WB
MOD UTYPRABOLPC:RABINDEX=1, SUBFLOWINDEX=0,
TRCHTYPE=TRCH_DCH, DELAYCLASS=1, BLERQUALITY=-27，
MAXSIRSTEPUP=1500, SIRADJUSTSTEP=3,
INITSIRTARGET=112, MAXSIRTARGET=152, MINSIRTARGET=82;
H
MAXSIRSTEPUP
SIRADJUSTSTEP
INITSIRTARGET
MAXSIRTARGET
MINSIRTARGET
BLERQUALITY
MAXSIRSTEPUP
SIRADJUSTSTEP
INITSIRTARGET
MAXSIRTARGET
MINSIRTARGET
BLER coefficient
optimization
RNC PERFENH_OLPC_BLER_COEF_ADJUST
SET UCORRMPARA：
PerfEnhanceSwitch=PERFENH_OLPC_BLER_COEF_ADJUST-1；
H
Solution1-Wireless Parameter Optimization with High Priority
Increase user downlink TX power: Increase voice downlink power, DL EVQI increase 0.03~0.1.
Constriction for UL BLER: Better OLPC enables UE to converge to better BLER target value faster, UL EVQI increase 0.01~0.05.
BLER coefficient optimization in light load: Better BLER target value in light load.

9. HUAWEI TECHNOLOGIES CO., LTD. Huawei Confidential 9
Sub-solution Feature ID Feature Name
Introduce
d in
Priority
Dependency on
PFM CHECK
RAN CN UE
Basic HD
WRFD-010613 AMR-WB (Adaptive Multi Rate Wide Band) RAN6.0 H RNC software Yes Yes
WRFD-011600 TFO/TrFO RAN3.0 H RNC software Yes No N/A
WRFD-140201 AMR Voice Quality Improvement Based on PLVA RAN14.0 H NodeB: WBBPd or later No No N/A
Best Experience
WRFD-160204 CS Voice Precise Power Control RAN16.0 H RNC software No No
WRFD-170201 Seamless Crystal Voice RAN17.1 H RNC: DEUa/EGPUb No No
WRFD-171201 Crystal Voice in Deep Coverage RAN17.1 H RNC: DEUa/EGPUb No No
Fastest Access
N/A Adaptive SRB Rate RAN16.0 H RNC software No No N/A
WRFD-171202 Ultrafast CS Call Setup RAN17.1 H RNC software Yes No
Speech Quality
Assessment and
Maintenance
N/A EVQI RAN16.0 H RNC software No No
WRFD-160102 Garbled Noise Detection and Correction of AMR Voice RAN16.0 H RNC software No No
WBAMRTRFO: Basic HD use AMR-WB and TrFO to improve voice quality, EVQI increase about 0.2~0.4.
Power Control Feature: Better experience by power control, EVQI increase about 0.01~0.02.
Crystal Voice: Best experience by DEUa/EGPUb decoding in RNC side, EVQI increase about 0.01~0.05.
Solution2-HD Voice Feature Optimization

10. HUAWEI TECHNOLOGIES CO., LTD. Huawei Confidential 10
Reason Ratio TOP Cells Optimization Suggest
IUB transmission limit IUB transmission check and optimization
ECNO limit(<-16dB) RF optimization
RSCP limit(<-100dBm) RF optimization
RTWP limit(>-95dBm) RTWP check and optimization
In compress mode state RF optimization
TX power limited RTWP check and RF optimization
PSC conflict
PSC check and optimization according to table
<Voice quality analysis result>
Missing Neighbor
Neighbor check and optimization according to
table <Voice quality analysis result>
Transmission check and optimization
RF optimization, PSC conflict and Neighbor check and optimization
RTWP check and optimization
Solution3-Network Basic Optimization

11. Copyright©2011 Huawei Technologies Co., Ltd. All Rights Reserved.
The information in this document may contain predictive statements including, without limitation, statements regarding the future financial and
operating results, future product portfolio, new technology, etc. There are a number of factors that could cause actual results and
developments to differ materially from those expressed or implied in the predictive statements. Therefore, such information is provided for
reference purpose only and constitutes neither an offer nor an acceptance. Huawei may change the information at any time without notice.
Thank you
www.huawei.com

12. HUAWEI TECHNOLOGIES CO., LTD. Huawei Confidential 12
Clarification for UL Bler Constriction Optimization
Mechanism
Advantage
Impact
Improve ULBLER and MOS
Script(RNC)
SET UCORRMPARA: PerfEnhanceSwitch=PERFENH_OLPC_BLER_COEF_ADJUST-1；
MOD UTYPRABOLPC:RABINDEX=0, SUBFLOWINDEX=0, TRCHTYPE=TRCH_DCH, DELAYCLASS=1,
BLERQUALITY=-27, MAXSIRSTEPUP=1500, SIRADJUSTSTEP=3, INITSIRTARGET=112,
MAXSIRTARGET=152, MINSIRTARGET=82;
MOD UTYPRABOLPC:RABINDEX=1, SUBFLOWINDEX=0, TRCHTYPE=TRCH_DCH, DELAYCLASS=1,
BLERQUALITY=-27, MAXSIRSTEPUP=1500, SIRADJUSTSTEP=3, INITSIRTARGET=112, MAXSIRTARGET=152,
MINSIRTARGET=82;
It is aimed to keep a good BLER by power control.
PERFENH_OLPC_BLER_COEF_ADJUST is a optimization and make BLER better when RNC is in light load.
BLERQUALITY is the BLER target value. Smaller is better.
MAXSIRSTEPUP, SIRADJUSTSTEP, INITSIRTARGET, MAXSIRTARGET, MINSIRTARGET make UE achieve BLER much faster.
Increase UL transmit power, which may influence UL capacity.
Application experience
Silent Ratio UL EVQI<3(%) UL EVQI RTWP
before after before after before after before after
case1 0.19% 0.17% 20.64% 14.65% 3.15 3.18 -101.56 -101.08
case2 0.15% 0.10% 30.52% 6.27% 3.25 3.54 -106 -105.96
Uplink Voice quality has a good improvement.

13. HUAWEI TECHNOLOGIES CO., LTD. Huawei Confidential 13
Clarification for Add Downlink TX Power Optimization
Mechanism
Advantage
Impact
To increase CS service power and improve voice quality.
Script(RNC)
MOD UCELLRLPWR: CellId=XX, CNDomainId=CS_DOMAIN, MaxBitRate=12200,RlMaxDlPwr=30, RlMinDlPwr=-120;
After the 12.2K is modified, add power of the 3.4k SRB channel (the configuration before the modification of the 12.2k power).
ADD UCELLRLPWR: CellId=XX, CNDOMAINID=CS_DOMAIN,MAXBITRATE=3400,RLMAXDLPWR=0, RLMINDLPWR=-150, DLSF=D256;
Dl power maximum and minimum values of power control
May cause TCP ratio a little increase. So suggested implemented in non TCP
congestion cells.
The downlink power couldn’t more than
Maximum_DL_Power,
The downlink power couldn’t less than
Minimum_DL_Power
Application experience
DL EVQI<3(%) DL EVQI
before after before after
case1 24.97% 12.53% 3.13 3.21
case2 9.14% 2.22% 3.50 3.59
The bad EVQI(<3) ratio and average DL EVQI both have a good improvement.