Drive Test Nemo 2
Transcript of Drive Test Nemo 2
Nemo Drive Test on 2G/3G
Networks
Toha Ardi Nugraha Trainer at Expert Coaching Clinic
Network Optimization Process
Reason of Drive Test?
1. Network Performance Monitoring
2. Maintenance
3. Benchmarking
4. Customer Complains
• Module 1 : Overview 3G System (1 hour)
• Module 2 : Drive Test Concept (1,5 hour)
• Module 3 : Drive Test on Field (2,5 hour)
• Module 4 : Reporting (2 hour)
• Module 5 : Analysis (2 hour)
OVERVIEW 3G SYSTEM
Module 1
Data Transmission
GSM & UMTS Evolution
3G/UMTS Architectures (Migration)
Specification of GSM
• Frequency band :
Uplink 890 – 915 Mhz
Downlink 935 – 960 Mhz
• Duplex spacing : 45 Mhz
• Carrier spacing : 200 khz
• Modulation : GMSK
• Access method : FDMA / TDMA
GSM network Architecture (cont’d)
• 3 Subsystem in GSM network
- BSS (Base Station Subsystem)
- NSS (Network and Switching Subsystem)
- OSS/OMC (Operating and Support system or
Operating and Maintenance Centre)
GSM network Architecture (cont’d)
BSS (Base Station SubSystem)
• BTS (Base Transceiver Station)
- Radio equipment
- To transmit and Receive signal to MS
- Defined a Cell coverage
depend on the power transmit
• BSC (Base Station Controller)
- RRM for several BTS
- Handover management
• TRAU
- Rate adaption
GSM network Architecture (cont’d)
NSS (Network and Switching Sub System)
• MSC (Mobile Switching Centre)
• HLR (Home Location Register)
• VLR (Visitor Location Register)
• AuC (Authentication Center)
GSM network Architecture (cont’d)
Operation and Support System
• Control and Monitor the Network
- NMC (Network Management Centre)
- Some OMC are controlled by NMC
- OMC (Operation and Maintenance Centre)
GSM Frequency Bands
GSM type Frequency Band
Uplink (UL) Downlink (DL)
GSM 900 890-915 Mhz 935-960 Mhz
GSM 1800 (DCS 1800) 1710-1785 Mhz 1805-1880 Mhz
GSM 1900 (PCS 1900) 1850-1910 Mhz 1930-1990 Mhz
GSM Channelization
• Physical Channel
– 200 Khz (Frequency Carrier) consist of 8 TS
• Logical Channel
– Control Channel
– Traffic Channel
Control Channel
Traffic Channel
GSM channelization (Cont’d)
Logical channel
Chontrol Channel
Broadcast channel
Common Control Channel
Dedicated Control Channel
Traffic Channel
Full Rate Half rate
3G/UMTS Concept
• WCDMA Concept
• UMTS Architecture
• Channelization
• Handover
WCDMA - Wideband CDMA
• Radio access technology for one of the UMTS access
modes (UTRA FDD) using 5 MHz duplex channels.
– Frame length is of 10 msec, Chip rate is 3.84 Mcps
– All users share the same frequency and time domain
– Users separated by the codes
UMTS Radio Frequency Ranges
• FDD (Frequency Division Duplex)
• TDD (Time Division Duplex)
Channelization in UMTS
• Logical Channel between RLC
and MAC
– Specific for information types
– What type of data to be
transferred
• Transport channel between MAC
and PHY
– Specific for “how to transfer
information?” (quality guarantee)
– How and with which type of
characteristic the data is
transferred by the Physical
Layer
• Physical Channel – Exact Physical characteristics of the
radio channel
WCDMA Channel (Cont.'s)
• Spreading means increasing the signal bandwidth
• Spreading includes two operations – Channelization (increases signal bandwidth)
• Orthogonal Spreading
– Scrambling
(does not affect the signal bandwidth) • Use pseudo-noise codes
Handover Concept
Site B Site A
BSC
Posisi 1
Posisi 2
Posisi 3
Handover
Request
Handover
Request
Handover Req
Acknowledge
Handover Req
Acknowledge
Handover Req
Acknowledge
Handover
command Handover
Complete
Handover: Types (2G)
• Intracell handover
– MS moves from one sector to another sector within same cell
• IntraBSC handover
– MS moves from cell to another cell within same BSC
• IntraMSC handover
– MS moves from cell to another cell from different BSC within same MSC
• InterMSC handover
– MS moves from cell to another cell from different BSC and different MSC
Handover: Types (3G)
• Intra-System handovers
– Intra-frequency handovers
• Soft, Softer
– Inter-frequency handovers
• Hard
• Inter-System handovers
– Handover between
WCDMA <> GSM (Hard)
– Handover between
WCDMA/FDD <> TDD
(Hard)
Pilots Set
The handset considers pilots in sets
– Active : pilot of sector actually in use
– Candidate : pilots mobile requested,
but not yet set up & transmitting by
system
– Neighbors: pilots told t mobile by
system, as nearby sectors to check
– Remaining: any pilots used by system
but not already in the other sets
Soft Handover Algorithm
AS_Th – AS_Th_HystAs_Rep_Hyst
As_Th + As_Th_Hyst
Cell 1 Connected
Event 1A
Add Cell 2
Event 1C
Replace Cell 1 with Cell 3
Event 1B
Remove Cell 3
CPICH 1
CPICH 2
CPICH 3
Time
Measurement
Quantity
T T T
DRIVE TEST CONCEPT
Module 2
Network Environment
• UMTS Drive Test is testing and measuring performance of
3G/UMTS network.
• Tools :
1. Software Nemo Outdoor
2. PC laptop
3. GPS
4. Scanner
Reason of Drive Test?
• Network Performance Monitoring
• Maintenance
• Benchmarking
• Customer Complains
Continuous Drive Test
• Drive Test (outdoor)
– GPS
• Walk Test (indoor)
– Pin point/way point
Analyze Data Collection
• Analyze data that was collected before
(from Log files)
• To know some problems in current area
Reporting
• To Answer Analyze Data Collection (Objective
Answer)
• Optimization Consideration
• Recommendation
Parameters DT GSM
1. Rx Level
2. Rx Qual
3. SQI
4. Cell Id, BSIC
5. TA (Timing Advance)
6. ARFCN, etc
Parameters DT UMTS
• UARFCN (UMTS Absolute Radio Frequency Channel
Number)
• RSCP (Receive Signal Code Power)
• RSSI (Receive Signal Strength Indicator)
• SC (Scrambling Code)
• Ec/No
• UE TxPower (dBm)
• Throughput
• BER, etc
• Step 1:
Start >“Settings”> “Control
Panel” > “System”
Or “My Computer” >
“Manage” > “Device Manager”
Open Device Manager
• Step 2: Choose “Hardware”
Tab in System Properties >
Click “Device Manager”.
Open Device Manager
• Step 3 :
• Look port to
conect hardware
(Modem)
• Scanner/GPS &
Check COM
Ports
Connect UE & Check COM Ports
• Double click the “3G
Modem” to check Trace
port number > Check
under “Modem” Tab.
• For UE Modem:
– In device manager
view:
Start Nemo Outdoor 5.07 and Load
Workspace
• Make sure the Nemo dongle is connected to the laptop.
• Launch Nemo Outdoor 5.07.
• Load the desired workspace.
• Workspace should contains adequate information for the
user to monitor.
• Different workspace should be created for different setup
configuration.
• Nemo workspace are stored proper folder for easy
access, eg.
C:\Nemo Tools\Nemo Outdoor\Workspaces
Running Program
Start >Program Files > Nemo Tools > Nemo Outdoor 5
• Workspace
• Details
• Device Configuration
• Load a measurement
User Interface Nemo Outdoor 5
Worksheet
Device graph
Load Workspace
• Step 3: Browse to Nemo Workspace Folder -> Select “workspace” >
Click “Open”.
Create Workspace
• Parameter
Add Devices
• Step 1: Go to “Measurement” workspace > “Add New Device”.
• Step 2: Click the “Configuration” part
> “Trace port” and “Modem port”
Nemo Interface
• Map Interface
– Open map (.tab)
• Nemo logfiles and other files are stored proper folder for easy
access, eg.
C:\Nemo Tools\Results (.nmf)
DRIVE TEST ON FIELD (OUTDOOR)
Module 3
REPORTING
Module 4
Map Info
• Exporting from Nemo Outdoor
– Select Parameters
• Reporting KPI with Map Info
• Layer Control
– Symbol
• Create Thematic Map
• Define Network Performance
• Open Table
Export to Map Info
Select Parameters
Report KPI With Mapinfo
• KPI (Key Performance Indicator) : key to detemaint Network performance.
like as , RSCP, Ec/No, etc
• Mapinfo is Software for loading and mapping geogharphic analysis
• File > open file (chose file
extention .tab)
• Ex : bandung.tap
• Used Layer control
Open Log files
• Example file (.tab)
Layer Control
• Command:
– View
– Edit
Create Symbol
Create Thematic Map
Create Thematic Map (Cont.'s)
Create Thematic Map (Cont.'s)
Reporting with Map Info
Open Table
ANALYSIS (TUNING THE NETWORK)
Module 4
UMTS Optimization
• 3 Mayor Steps in Optimizing Network
• UMTS performance indicator
• Problem Signature
• Tuning network
– Specific Neighbor list
– Managing excessive soft handoff
3 Mayor Steps in Optimizing Network
• RF optimization is the process of measuring,
• analyzing, and tuning and existing network to meet
network performance criteria
• It usually occurs after the network planning is completed
• It can be performed frequently to respond:
– Changes or growth in the network
– Customer complaints such as coverage,
dropped call etc.
– The need to improve capacity.
UMTS Performance Indicator
KPI Target :
– RSCP (good > -85 dBm)
– Ec/No ( > -8 dB)
– BER (98%)
– Analyze Pilot Pollution Area
– Drop Call Rate (DCR)
– HSR (Handover Success Rate)
– Call Setup Success Rate (CSSR)
Problem Signature
• Missing Neighbor or No Neighbors defined for
Site. (Database)
• Poor Coverage Area.
• Pilot Pollution Area
Poor Coverage Area
• Test mobile measurements
• Antenna configuration check
• Verification of RF network design
• Propagation model verification
• Link budget analysis
Improving coverage
– Cell spliting, Sectorisation
• Difficult , Expensive
• Primarily used for capacity enhancement
– Overlaid cell structure
• Micro- and picocells
• Cellular repeaters
RNC
Node B
Node B
Node B
Node B
Pilot Pollution
• Active set UE > 3 and in range 5 dB or approximately 3
dB from the biggest active set.
• Reduce system performance,
Antenna Fine Tuning
• Horizontal plane
– Possible coverage weakness between sector
– Interference reduction
– Traffic load distribution
• Vertical Plane
– Interference reduction
– Possible coverage weakness in the short to medium
distance range
– Traffic load distribution
Tuning the Network
Solution (Antenna Adjustments)
Include :
– Down tilting
– Antenna Height
– Azimuth
– Type of antenna
Reason of Down tilting:
1 Reduce interference
2 Optimizing cell
Antenna Configuration
• General points to check
– antenna type, e.g.
• omni
• directional 60, 90 or 120 degrees
• electrical downtilt
– antenna azimuth angle (for directional antenna)
• coverage targets
– antenna tilt angle
• electrical + mechanical
– diversity & isolation
• e.g. space diversity,
• polarisation diversity
Type Antenna Down tilt
Mechanical down tilt
– Physic, Sectoral
Electrical down tilt
– Easy
0 ° 0 °
Electrical Mechanical
Typical antenna beam pattern
Omni vs. Sectorised
• OMNI cells - more difficult to optimize – Electrical down tilt possible, however
• same for entire cell
– Parameters same for entire cell
• Directional antenna – narrower beam easier to control interference
– tilting less efficient with wider beams
Sectorised cell site with different
downtilt angles
Reference
• Short Course “In Building DCS 1800 Coverage”, Mobile
Communication Laboratory, 2009
• Short Course “Drive Test UMTS”, Mobile Communication
Laboratory, 2008
• Short Course “Drive Test CDMA 2001x and Optimization”, Mobile
Communication Laboratory, 2008
• Short Course “CDMA Drive Test and Optimization”, Antenna
Laboratory, 2007
• Nemo_Outdoor_manual
Thanks