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Page 1
Contents
1. U900 / U2100 Strategy
(by Relative EcNo, or U2100 Absolute EcNo, or in High RTWP)
2. U900 / GSM Strategy
(Keep 3G users in 3G)
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3. U900 / LTE Strategy
(Reselection & Fast Return by priorities)
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Page 2
U900/U2100 Strategy Overview
Strategy for Normal RTWP cells:
 U900 as coverage layer because U2100 cannot effectively cover.
 U2100 as capacity layer because U2100 has more bandwidth/capacity. It’s
preferred layer.
 Subscribers in cell center go to U2100, and subscribers in cell edge go to U900.
U2100
U900
U2100->U900: try to camp as long as possible to U2100 layer before to reselect
U900, in order to maximize the benefit of U2100 capacity and more HSPA feature
like DC.
U900->U2100: reselect when U2100 coverage level reached.
Strategy for High RTWP cells:
 U900 as capacity layer because UEs in cell edge cannot make access in high
RTWP cells.
 U900 is allowed to absorb CS+PS traffic from U2100 bases on load threshold.
 High RTWP sites do not block U900 deployment with this strategy.
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U2100
Load Suffering
U900
Page 3
U900/U2100 Service Strategy
Idle Mode: Free Camping Strategy
U900 F1
U900 F1
U2100 F1
U2100 F1
U2100 F2
Connected Mode:
HO based on Coverage and Traffic Load
U900 F1
U900 F1
U2100 F1
U2100 F2
U2100 F2
G900
U2100 F1
U2100 F2
G900
Traffic -based
G1800
Coverage-based
G1800
Reselection
U2100 F1
U2100 F2
Blind IFHO LDR
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Load Balance
DRD
Measurement based LDR
Coverage-based CS & PS
IFHO/ CS IFHO
Load Balancing Strategy:
Cell central user, U2100/G1800, Better User Experience;
Cell border user, U900/G900, Better Deep Coverage Experience.
For U900 Dual Carrier solution, U900 F2 links to U2100 F2.
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Page 4
Strategy 1: Cell Reselection by Relative EcNo
1
U2100
U9U21 reselection by
relative EcNo.
Trigger Condition:
U9 ≤ (U21 EcNo + offset)
Low Band in
Heavy Load due to
Bigger Coverage
U21U9 reselection by
relative EcNo.
Trigger conidtion:
U21 ≥ (U9 EcNo – offset)
Busy Hour Mode
Capacity +5%~20%
due to precise
balance
U900
Cell reselection is to trigger according to Relative EcNo between
U900 and U2100.
Adaptive with Inter-band Load Balance feature. Auto optimization.
Challenge: easy to trigger cell reselection, worse KPI.
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Unbalance in
Busy Hour
U900
U2100
U900
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U2100
WRFD-171214 Inter-Band Load Balancing, RAN17.1.
Increase system capacity by 5~20%.
Improve user’s experience.
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Page 5
Strategy 1: Parameter Settings
S0023
U900: 2308
S0024
U2100: 2302
U2100: 2401
Parameter（Ref）
U900
ADD UCELLSELRESEL
Qqualmin
-18dB(-18)
-18dB(-18)
Qrxlevmin
-115dBm(-58)
-115dBm(-58)
Qhyst2
2dB(1)
2dB(1)
IdleSintrasearch
10dB(5)
10dB(5)
IdleSintersearch
12dB(6)
8dB(4)
ConnSintrasearch
10dB(5)
10dB(5)
ConnSintersearch
8dB(4)
8dB(4)
S0025
ADD UINTERFREQNCELL
IdleQoffset2sn
U2100: 2501
InterNCellQualReqFla
g
Reselection parameters should be set for U900 cell and all
neighboring U2100 cells.
U2100 F1
-3dB->U2100 F1www.huawei.com
3dB->U900 F1
TRUE
NA
Qqualmin
-12dB(-12)
NA
Qrxlevmin
-101dBm(-51)
NA
Marked parameters are changeable to adjust
U900/U2100 load. Other parameters are static.
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Strategy 2: Cell Reselection by Absolute U2100 EcNo
U2100
U9->U21 reselection
by U21 EcNo.
Trigger Condition:
U2100 EcNo ≥ (X)
U21->U9 reselection by
U21 EcNo.
Trigger Condition:
U2100 EcNo ≤ (X-2)
MR Samples (Mil.)
U2100 Reselection Threshold (X)
300
X = 12dB
250
200
150
Edge traffic
goes to U900
100
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50
U900
0
-23 -22 -21 -20 -19 -18 -17 -16 -15 -14 -13 -12 -11 -10 -9 -8 -7 -6 -5 -4 -3 -2
U2100 EcIo (dB)
Cell reselection is to trigger according to Absolute U2100 EcNo.
Compared to strategy 1, this strategy is easier to control cell load.
Absolute EcNo could avoid large number of cell reselection, better for
KPI.
This strategy does NOT adapt with Inter-band Load Balance feature.
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Threshold X should be -10~ -16 dB.
Reselection thresholds must be calculated properly
in cell-level according to EcIo curve and number of
U2100 carriers. Otherwise U900 may get congestion.
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Page 7
Strategy 2: Parameter Settings
Parameter
Qqualmin
S0023
Qrxlevmin
U900: 2308
S0024
U2100: 2302
U900
U2100 F1
ADD UCELLSELRESEL
-18dB(-18)
-18dB(-18)
U2100: 2401
S0025
U2100: 2501
-115dBm(-58)
Qhyst2
2dB(1)
2dB(1)
IdleSintrasearch
10dB(5)
10dB(5)
IdleSintersearch
18dB(9)
4dB(2)
ConnSintrasearch
10dB(5)
10dB(5)
ConnSintersearch
18dB(9)
4dB(2)
ADD UINTERFREQNCELL
IdleQoffset2sn
InterNCellQualReqFlag
Qqualmin
Qrxlevmin
Reselection parameters should be set for U900 cell and all
neighboring U2100 cells.
-115dBm(-58)
-20dB->U2100 F1 0dB->U900 F1
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TRUE
-12dB(-12)
-115dBm(-58)
NA
NA
NA
Marked parameters are changeable to adjust U900/U2100
load. Other parameters are static.
Reselection settings need to refer radio quality distribution.
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Page 8
Strategy 3: Res/Ho in High RTWP scenario
Key points and Gains
U900 UL
U900 UL
RTWP = -80dBm
U900 F1
Key Points:
 IDLE: increase min quality level (RSCP), UEs in cell
RTWP = -65dBm
edge do not allow access.
U900 DL
U900 DL
 CONN:
Edge
Edge
Edge
 Increase 2D/2F threshold (RSCP), handover over to
U2100 quickly when UE moved to cell edge.
 Handover based on target cell RTWP, to avoid call
Call
Access
drop after HHO.

Normal
HHO
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WRFD-171213 is optional feature in RAN17.1 for high
RTWP cells. Before RAN17.1, strategy and parameters
should be defined manually.
Earlier
HHO
Gains:
Consider when network level has got serious interference.
Restrict call access in cell edge, and set earlier HO to other cells.
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Reduce KPI impact in high RTWP cells.
High RTWP cells can be used for load sharing with U2100.
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Page 9
GSM/UMTS Strategy: Keep 3G users in 3G
IDLE mode GU Reselection
CONN mode GU Handover
U2100/U900
G2U Reselection:
U2100/U900
U2G Reselection:
When 3G Ncell RSCP>-104dBm
& EcNo>-12dB
When 3G Service Cell EcNo < 14dB & 2G Ncell RxLev>-95dBm
FDDRSCPMIN=-104dBm
(from -100dBm, for some cells)
FDDQMIN=-12dB
SsearchRat=4dBm
Qqualmin=-18dBm
Qrxlevmin=-95dBm
G2U CS Handover:
When 3G Ncell EcNo>-9dB
U2G CS Handover:
INTERRATOUTBSCHOEN=YES
(from NO)
BET3GHOEN=YES (from NO)
HOECNOTH3G=-12dB (from 0dB,
final EcNo is plus Offset 3dB)
G2U PS Handover:
Enabled.
QP = Always
G1800/G900
When 3G Service Cell EcNo<-15dB
or RSCP <-106dBm
IRAT CS EcNo 2D/2F = -15/-12 dB
IRAT CS RSCP 2D/2F=-106/-103 dBm
U2G PS Handover:
When 3G Service Cell No<-18dB or
RSCP <-110dBm
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IRAT PS EcNo 2D/2F=-18/-15 dB
IRAT PS RSCP 2D/2F=-110/-107 dBm
G1800/G900
Coverage-Based Cell Reselect
Coverage-Based HO
Try to keep 3G users in 3G at most, since the user experience is better than 2G, even in 3G cell border.
3G provides higher throughput (HSPA), Multi-RAB (CS+PS), and better MOS in voice.
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Page 10
GSM/UMTS Strategy Parameters
IDLE Reselection Key Parameters
NE
Command
Parameter
G900->U900 Coverage-Based Reselection
INTERRATCELLR
ESELEN
SET GCELLHOBASIC
LTECELLRESELE
N
GERANPRI,
SET
UTRANPRI,
GCELLPRIEUTRANSYS
EUTRANPRI
Recommend
ed
Scenario
NO
YES
GU&GUL
NO
YES
GUL
L>U>G
GUL
Default
UTRANQRXLEVMI
N
THRUTRANHIGH
SET
GCELLPRIEUTRANSYS EUTRANQRXLEV
MIN
THREUTRANHIG
H
SET
GCELLCCUTRANSYS
BSC
SET
GCELLCCUTRANSYS
FDDRSCPMIN
FDDQMIN
SI2QUATEROPTI
MIZEDALLOWED
GUL
2
2
GUL
6
4
GUL
6
6
GUL
5
5
GUL
6 (-102dBm)
5(-104dBm)
GU
7 (-12dB)
7(-12dB)
GU
NO
YES
GU&GUL
ON
GU&GUL
BCCHExt
GUL
ON
GUL
OFF
G2U switch on
RNC
ADD UCELLSELRESEL
ADD U2GNCELL
SsearchRat
CPICH_ECNO CPICH_ECNO
Command
GU&GUL
2
2(-14dB)
GU&GUL
Qqualmin
-18
-18dB
GU&GUL
Qrxlevmin
-50
-48(-95dBm)
GU&GUL
RNC
Parameter
Early to trigger:
>-118dBm
INTERRATPINGPONGTIME
R
ADD
InterRATCSThd2DEcN0
UCELLINTERRATH InterRATCSThd2FEcN0
OCOV
InterRATCSThd2DRSCP
InterRATCSThd2FRSCP
G900->U900 CS Handover: Fast to trigger
SET
INTERRATOUTBSCHOEN
GCELLHOBASIC
QCI
SET
GCELLCCUTRANSY
QSEARCHC
S
FDDREP
Early to trigger:
>-107dBm
BSC
ADD GEXT3GCELL MINECNOTHRES
ADD G3GNCELL
Early to trigger.
Optimization
U900->G900 Coverage-Based Reselection
QualMeas
NE
Default
Recommend
Scenario
0
10
GU&GUL
-14
-12
-15
-12
GU&GUL
GU&GUL
-100
-106
GU&GUL
-97
-103
GU&GUL
YES
GU&GUL
Always
GU&GUL
7 (Always)
GU&GUL
EcNo
GU&GUL
Remark
U900->G900 CS Handover
L>U>G
FirstSI2QuaterMsg
OFF
OptSw
POS2QUATER
BCCHNorm
SET
SI2QUATEROPTF
GCELLPRIEUTRANSYS ORLTESW
Remark
Follow strategy
design
ADD GLTENCELL /
NCELLPRI
G3GNCELL / G2GNCELL
BSC
CONN Handover Key Parameters
Late to trigger:
Scell < -14dB &
2G Ncell >95dBm
ECNOOFF
HOOPTSEL
BET3GHOEN
SET
GCELLHOUTRANF
HOECNOTH3G
DD
U900->G900 PS Handover
MOD
HoSwitch UCORRMALGOSWI HO_INTER_RAT_PS_OUT_S
TCH
WITCH
InterRATHThd2DEcN0
RNC
ADD
InterRATHThd2FEcN0
UCELLINTERRATH
InterRATHThd2DRSCP
OCOV
InterRATHThd2FRSCP
G900->U900 PS Handover
SET
BSC
GCELLCCUTRANSY QP
S
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TECHNOLOGIES
CO.,
HUAWEI
CO.,for
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Above
is theTECHNOLOGIES
key parameters,
other parameters related
to IRAT
Res/HO can
beLTD.
set to default.
NO
Use_Qsearc
h_I
7 (Always)
EcNo
25 (-12dB)
25 (-12dB)
3 (dB)
3 (dB)
Pre_2G_Cell
Pre_3G_Cell
Thres
NO
YES
Late to trigger
U2G CS HO.
Early to trigger
G2U CS HO.
GU&GUL
GU&GUL
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GU&GUL
GU&GUL
35(-6.5dB)
24(-12dB)
GU&GUL
1
1
GU&GUL
-15
-13
-18
-15
GU&GUL
GU&GUL
-110
-110
GU&GUL
-107
-107
GU&GUL
7 (Always)
7 (Always)
GU&GUL
Early to trigger
G2U CS HO, but
2G KPI may
degrade.
Late to trigger
U2G PS HO. Can
be switch off.
G2U PS HO
Enabled
Page 11
U900/LTE Service Strategy (IDLE & CONN)
Note: U900 is planned to deploy with L800 so that 3G coverage
High 6
High 5
always exists with LTE.
L2600
IDLE Mode:
L1800
LU: UE reselects to UMTS bases on coverage (First measure
U2100, then U900)
L800
High 4
UL: UE reselects to LTE bases on priority (L2600>L1800>L800)
Medium 3
LG: No reselection. U900 coverage is ≥ G900
U2100
GL: No reselection. U900 coverage is ≥ G900
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Medium 2
CONN Mode:
U900
LU CSFB: Enable Flash CSFB based on Measurement to UMTS.
Low 1
First measure U2100 then measure U900.
G900
UL Fast Return: based on priority: L2600 > L1800 > L800
Coverage-based Cell Reselection
Flash CSFB
Priority-based Cell Reselection
Fast Return
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UG CSFB: Disable Flash CSFB to GSM.
G Fast Return: Disable Fast Return to LTE.
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Thank you
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differ materially from those expressed or implied in the predictive statements. Therefore, such information is provided for reference purpose only and
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