gci presentation(asep gci-0573)

Jr. RNO

GCI Science & Technology Co., Ltd.Planning and Design Institute of Communication Engineering

ASEP JAJANG NURJAYA2013-ZTE-SMART-MDN-RNO-RO

HEADLINEGCI Science & Technology Co., Ltd.

Planning and Design Institute of Communication Engineering

CDMAGCI Science & Technology Co., Ltd.


OPTIMIZATION FLOW CHARTGCI Science & Technology Co., Ltd.


New Site Integrated

Single Site Verification

RF Optimization

Cluster of Sites Ready?

Service Test and Parameter Optimization

Regular Reference Route Testing and Stats Analysis

Re-optimization Needed?

Y

N

N

Y

OPTIMIZATION FLOW CHARTGCI Science & Technology Co., Ltd.


• Single Site VerificationTo verify the functionality of every new site.

• ObjectivesTo ensure there are no faults related to site installation or parameter settings.

• RF Optimization– Once all the sites in a given area are integrated and verified, RF (or

Cluster) optimization could begin. • Objectives

– To optimize coverage while in the same time keeping interference and pilot pollution under control over the target area. This phase also includes the verification and optimization of neighbor lists.

DRIVE TEST ANALYSISGCI Science & Technology Co., Ltd.


• Cells with no dominance at all– A site was not radiating during the drive survey– Very poor dominance can also be caused by blocking of the antenna.

So a site visit must be made to verify the antenna clearance.• Cells with either excessive or poor dominance

– This could be due to a high site or non-optimum antenna tilts. – Cells with too large dominance will be causing interference to

adjacent cells resulting in poorer capacity.

OPTIMIZATIONGCI Science & Technology Co., Ltd.




Bad Ec/Io

Ec/Io = (2/8) = 0.25 = -6dBEc/Io = (2/40) = 0.05 = -13dB



OVERSHOOTING CELLS CAUSING BAD Ec/Io



ANTENNA TILT CAN SOLVED THE PROBLEM



ON SITE OPTIMIZATION

E. TILT M. TILT AZZIMUTH



CALL RELEASE FAIL CAUSED BY MISSING NEIGHBOR



ADDING NEIGHBOR IN OMC SIDE CAN SOLVED THE PROBLEM



CALL ATTEMP FAIL CAUSED BY NO BEST PN AVAILABLE



INCREASE TRANSMIT POWER AND TILTING CAN SOLVED THE PROBLEM



Drop Call Analysis - RF related issues :Poor coverage High interference and hence poor Ec/IoPoor uplink coverage (insufficient UE Tx power)Poor dominance (best cell changes too frequently resulting in too many SHO events)Pilot pollution (too many cells serving)Missing neighborsFast change of RF conditions



HANDOVER FAIL DUE TO WRONG PN

Other cell can’t do handover to micro cell which has PN 481 due to the PN is not multiple of 3 according to PN_inc parameter on OMC side



CHANGE PN CAN SOLVED THE PROBLEM

Change PN using the number of multiple by 3 can solved the problem, for instance PN 483



OTHER PROBLEMS DUE TO ALARM

LAYER MESSAGEGCI Science & Technology Co., Ltd.


HANDOVER PARAMETER



HANDOVER PARAMETER

1

2

3

4



HANDOVER PARAMETER

5

67

8



HANDOVER PARAMETER(note description)

1. Power control step size used by MS usually 1dB each step2. Power level of the forward link power control3. Channel indicator

4. Quasi orthogonal function index



HANDOVER PARAMETER(note description)Pilot Detection Threshold (T_ADD)Any pilot that is strong but is not in the HDM is a source of interference. This pilot mustbe immediately moved to the active set for handoff to avoid voice degradation or a possibledropped call. T_ADD affects the percentage of mobiles in handoff. It should be low enough toquickly add useful pilots and high enough to avoid false alarms due to noise.Comparison Threshold (T_COMP)It has effect on handoff percentage similar to T_ADD. It should be low for faster handoffand should be high to avoid false alarms.Pilot Drop Threshold (T_DROP)It affects the percentage of mobiles in handoff. It should be low enough to avoid droppinga good pilot that goes into a short fade. It should be high enough not to quickly remove usefulpilots in the active or candidate set. The value of T_DROP should be carefully selected by consideringthe values of T_ADD and T_TDROPDrop Timer Threshold (T_TDROP)It should be greater than the time required to establish handoff. T_TDROP should be smallenough not to quickly remove useful pilots. A large value of T_TDROP may be used to force amobile to continue in soft handoff in a weak coverage area.



HANDOVER PARAMETER(note description)6. Pilot increment describe how many PN number will increase every step7. Neighbor search mode

8. Default search window size to be used by the MS for its neighbor set



SEARCH WINDOWIf a search window is too small, the important pilot signal will be lost, thus resulting in interference.if it is too large, the search efficiency will decrease, and the conversation quality will be compromised.

Default DO search window configuration in Medan OMC SRCH_WIN_A = 8 SRCH_WIN_N = 10SRCH_WIN_R = 10If 1X (A,N,R)= 6,8,10

http://www.teletopix.org/tag/interference



SEARCH WINDOW

Default setting

OPTIMIZATION REPORTGCI Science & Technology Co., Ltd.


KPI INDICATOR MOBILE TEST CASES 800 & 1900MHzAT Originated Connection Setup Success Rate > 95% > 95%AN Originated Reactivation Success Rate > 95% > 95%AT Originated Reactivation Time < 5 sec < 5 secAT Originated Connection Setup Time < 1 sec < 1 secConnection Drop Rate < 2% < 2%Single User Forward Link Throughput Distribution (TCP) at mobile route > 800 Kbps > 800 Kbps

Single User Reverse Link Throughput Distribution (TCP) at mobile route > 300 Kbps > 300 Kbps

Soft Handoff Success Rate >= 99% >= 99%Hard Handoff Success Rate(Inter BSC, Inter MSC, Inter Carrier, Inter Band) >= 85% >= 85%

Single User Packet Error Rate during Mobility < 1% < 1%

C/I distribution >5 dB (95% samples)

>5 dB (95% samples)

OPTIMIZATION REPORTGCI Science & Technology Co., Ltd.


KPI INDICATOR ON OMC SIDE USING CNO2 SOFTWARE

LOG FILE ANALYSISGCI Science & Technology Co., Ltd.


PROBLEM CONCLUSIONCOVERAGE1. Low Signal Level (In areas where there are few sites and too many different types

of terrain structure)2. Lack of dominant server (This might be happen because the MS located on the cell

borders and there is no best server to keep the call)3. Sudden Appearance and Disappearance of neighbors ( due to terrain or obstacles,

neighbors may pop up with high levels causing the BSC to give wrong handover decisions)

4. RX levels too closed to each other (This might point overlapping cells, other cells else than the one that supposed to serve at that particular area should be coverage reduced by power reduction, down tilt or other configuration changes)

THANK YOU

GCI Science & Technology Co., Ltd.Planning and Design Institute of Communication Engineering

ASEP JAJANG NURJAYA2013-ZTE-SMART-MDN-RNO-RO

gci presentation(asep gci-0573)

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