Guidance Report Drivetest and Anlysis KPI

GUIDANCE OF LTE REPORT DRIVETEST AND KPI ANALYS

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Over View

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Making Routes

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Processing Tools

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Reporting

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Analysis

LTE Mentor by Iwan Purnawirawan

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Highlights      

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Making and Modify Cellfile Format Input Cellfile on TEMS Investigation Input Site Databased to TEMS Discovery Make New Project by TEMS Discovery Input Drivetest Result on the Report Analyzing Measurement

Over View

Issues  Improvement Skill  Sharing Knowledge  Good Attitude in the work

Requirement Tools

Actions

 TEMS Investigation Version 16 or above

 Perform to Make Report And Analys

 TEMS Discovery Version 10 or above  Map Info Proffesional


Making Routes

3 LTE Mentor by Iwan Purnawirawan

Begin to make report should be prepared drivetest route for more information and get approved by owner and fill into the report

Note : All the making of a route can be done on all networks

Create & Modify Cellfile

Processing Tools

4 LTE Mentor by Iwan Purnawirawan

Note : Configuration Cell Site by TEMS Investigation

D:\Work\

Cellfile MYANMAR\NOKIA\GCELL\4G_Gcell\GCEL

Note : Configuration Cell Site by TEMS Discovery

Reporting

PARAMETER DRIVE TEST ON THE REPORT

2G - Rx Level

4G - SINR

3G - EcIo

2G - Rx Qual


4G - RSRP

3G RSCP

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PARAMETER DRIVE TEST ON THE REPORT

3G - PSC

Rx Lev, RSCP & RSRP : Receiving level signal in terms of dBm that mobile is receiving from the site. Range of -30 dBm to -110dBm. Rx Qual : Quality of voice which is measured on basis of BER. Range of Rx Qual 0 -7 SQI : This means that when optimizing the speech quality in your network, SQI is the best criterion to use. SQI is updated at 0.5 s intervals. It is computed on basis of BER and FER. For EFR 30, FR – 21 & HR – 17 are respectively ideal values.

2G - CI


4G - PCI

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LTE_SSV Report

Ec Io : Energy Chips per Interference Offset which is measured on basis of total energy chips. Range of -5 dB to -12 dB SINR : Energy Chips per Interference Offset which is measured on basis of total energy chips. Range of 10 to 30 3G_SSV Report

PCI, PSC, and CI : Parameter to indentify site had swap feeder or cross serving cell

2G SQI

SUMMARY KPI SSV/SSA & CLUSTER

Analysis & KPI

Summary Single Site Level

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Note : Based on Job desk, for SSV no need KPI except SSA ( Single Site Acceptance )


Summary Cluster Level

ANALYZING MEASUREMENT

Analysis & KPI

PROBLEM CASE Interference Signal by DL EARFCN Low Signal Coverage Handover Failure Inter Cell Overshoot Low Throughput CS Fall Back Issue


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Interference Case Large area DT

Post-Processing

Specific area DT

Analysis

 Identify areas with bad SINR > 5  Identify source using Map and STS or drive test result  New drive test around problem area


TEMS Logfiles

INPUT

From logfile & map: What carrier group suffer from interference? • Check carrier band information in TEMS INVESTIGATION Where does the interference come from ? Cell name? • Study map and logfile, look for carrier spectrum interference. Does the interference lead to lower RSSI ? • Look at RSSI measurement during bad SINR. Use STS & RNO to assist analysis.


Interference Case – Logfile analysis

Types of Interference • INTER-CELL INTERFERENCE (ICI)  In LTE, the smallest unit of radio resource that can be allocated to a user for data transmission during packet scheduling is called physical resource block (PRB).  time/frequency radio resource that spans over one time slot of 0.5ms in the time domain and one sub-channel (180 KHz) of 12 subcarriers in the frequency domain is known as resource block (RB)  When a user moves away from serving eNB and becomes closer to its adjacent eNB, the received SINR (Signal to Interference and Noise Ratio) degrades as the desired received signal power decreases and the ICI increases. The impact of inter-cell interference. Action Analyis : 

Conventional Frequency Reuse

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Fractional Frequency Reuse



Checking databased by DL EARFCN

TEMS Logfiles

INPUT Large area DT

Post-Processing

Specific area DT

Analysis

• Identify areas with low signal strength e.g. SS < -100dBm (outdoor) • Look at RSRP, RSCP, and Rx Level distribution (for acceptance) • Compare with design level or new requirements to network planning


Signal Strength Case

• Shadowed Antenna • Antenna Direction • Antenna Height / down tilt • Output Power • Missing Neighbor Relation • Site Location • Faulty Hardware e.g. antenna & TMA • Cell is down


Signal Strength Case – Possible Reasons to checking

Shadowed Antenna

Output Power

Faulty Hardware

Visit site

Check output power

Check antenna installation

Parameters

Check alarm & BTS Error log

Is there a better antenna position at same site?

BSPWRT - NON Burst FREQ

Visit site

Height/down Tilt

BSPWRB – RCVD PMAX

Missing Neighbor

Site Location

Add reduce down tilt?

Is the call dragged?

Possible to move site?

Can antenna be placed lower or higher to give better coverage?

Is low SS due to missing neighbor relations

New antenna location at same site? Is it necessary to expand and build a new site?


Signal Strength Case – Analysis

• Change parameter power. • Add neighbor relation. • Physical changes: • Antenna direction • Antenna height, tilting or position • New site as last option.


Signal Strength Case – Possible Solutions

Handover Case Large area DT

Post-Processing

Specific area DT

Analysis

Look for:

Repeated handover (Ping Pong) Repeated Intra-cell handover Handover failure, Unrealistic handover


INPUT

Repeated Handover Failure – Possible Solutions Antenna direction Antenna Tilts Define Neighbour Priority Change Locating Parameter e.g. KHYST or LHYST


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 Check layer 3 message ( event A3, A4, & A5 )  Handover command Node B/ eNode B correct ?  Check reason for handover SS, intra and inter HO, also SHO, IRAT ( event B1 and B2 )  LTE ( event 2a,2b and 3a,3b )


Handover Case – Handover Reversion

 Overshooting has leading cell will be bad SINR like this . Areas that should be covered by only one cell alone, could be covered by two or more other cell overshooting towards the area. Action Analysis • Change parameter power. • Add neighbor relation. • Physical changes: • Antenna direction • Antenna height, tilting configuration


Overshooting Case – Possible Solutions

Low Throughput Case – Root Cause • High Latency • Delay Round Trip Time • Lower Access service Time • High Package Loss Ratio

 To Get Better Throughput should be had RSRP > -85 dBm

 User Mobile in the main beam position

– Possible Solutions  Check PRB Alocation  Check RI ( Ring Indicator )  good value is 2  Check transmission mode   Good condition in TM3  Check Modulation Scheme  good condition is 64 QAM ( 6 symbol )

• Check configuration LTE aDJW ( adjacent to WCDMA ) • Check proxy by NAS Signaling • Check TAC ( Tracking Area Code ) in EUTRAN to UTRAN • Check IMSI number was define into core network or not ? • Escalated to core division from 3G side by Radio Access Network


CS Fall Back Case – Possible Solutions

Kyae Zu Tin Par Tal DO NOT GO BACK, BEFORE KPI ACHIEVED…!!! DO THE RIGHT THING AND GET IT DONE

APPLIED TECHNOLOGIES INTERNATIONAL CO., LTD.

Guidance Report Drivetest and Anlysis KPI

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