Drive test final
- 1. DRIVE TEST
- 2. Contents • NETWORK PROBLEM IDENTIFICATION • REQUIREMENT FOR DRIVE TESTING • DRIVE TEST PROCESS • DRIVE TEST OUTPUTS • MEASUREMENT METRICS • DRIVE TEST ANALYSIS • NEPTUNE AND PROBE
- 3. Network Problem Identification • Drive Test • OMC Statistics • Customer feedback
- 4. Requirement for Drive testing • Test the network from the subscribers’ point of view • Test the complete system, end-to-end (mobile-to-land) • Benchmark performance against competitor networks • Test specific important routes and areas • Test in-building coverage for specific buildings (walk test)
- 6. Drive Test Equipments • Data collected to find and analyze problems in the network • Equipment Necessary for Drive testing Vehicle Drive test mobile phone External vehicle mounted GPS Laptop with drive test software and GPS connection capability
- 8. General Consideration • Routes chosen to be representative of the part of the network under study • If possible simultaneously collect GSM speech and GPRS drive test data • Drive test to be carried out during normal daylight hours • Calls to be made preferably mobile-to-PSTN • Call duration to be equal to the average call duration for the network • At least 1000 calls required for good statistical confidence
- 9. Drive Test Types • Routine drive test • Problem specific drive test • Cell coverage analysis drive test
- 10. Routine Drive Test • Network to be monitored on a daily basis • Drive test routes to include all the major roads, important locations, etc • Routes regularly drive tested and problems further analyzed and solved • May require removing interfering carrier, Power Change to BTS, Frequency Plan change, Neighbor addition , etc.
- 11. Problem Drive Testing • Problems reported by statistical analysis, routine drive testing, customer care centre , alarms,etc • Requires problem specific drive testing • List of problematic cells identified and drive tested thoroughly to analyze the problem • Data collection and analysis done simultaneously
- 12. Cell Coverage Analysis Drive Test • Usually carried out for new planned sites in the network • New cells to come on air are thoroughly drive tested to determine their server and coverage areas • Optimisation to be carried out for any major deviation from the initially planned design
- 13. Optional Features • Walk test support • On line map display of the route • Scan feature
- 15. Display • Using the drive test equipment we can monitor the following o Status Information o Error reports o Layer 2 messages o Layer 3 messages
- 16. Display….. Status Information • General Information: Includes Latitude ,longitude data, server call name, Marker ,data, time , log file name etc • Serving cell: Includes Cell Identity, BSIC, ARFCN ,MCC, MNC, LAC • Serving + Neighbor cell data: Includes CI, BSIC, ARFCN, Rxlev • Dedicated channel:Includes Channel number, Timeslot number, Channel type,hopping information • Radio Environment: Includes serving cell, Rxlev, Rxqual, TA, DTX and RL Timeout counter information
- 17. Display….. Error reports • Errors reported during a call can be analyzed from this report Layer 2 messages • Layer 2 messages can be analyzed Layer 3 messages • Layer 3 messages can be analyzed
- 19. GSM Drive Test Metrics • Route Plots RxLev Full RxLev Sub RxQual Full RxQual Sub FER MS TX Power SQI • Events Call Drops Setup Failures HO Failures HO Success
- 20. GPRS Drive Test Metrics • Route Plot UL/DL RLC Throughput: Radio Link Layer data throughput UL/DL LLC Throughput: Logical Link Layer throughput (user data) UL/DL RLC Block Error Rate (BLER): Radio Link Block Error Rate UL/DL RLC Retransmission Rate: Radio Link Retransmission Rate UL/DL Coding scheme used (CS1-4): Allocated Coding Scheme UL/DL Number of timeslots used: Allocated timeslots • Events PDP Context Activation Failure: Failure to activate PDP Context (Packet Data Protocol) PDP Context Loss: Loss of PDP Context (GPRS Call Drop)
- 22. Analysis Types • Coverage Analysis: Level Analysis Quality Analysis • Interference Analysis: Co-channel and adjacent channel interference • Handover Analysis: HSR and HFR • Neighbor Analysis: Missing neighbors • Call Analysis: DCR,CSSR,CSR,Call Setup time,Call hold time etc. • Layer 2 Analysis • Layer 3 Analysis
- 23. Level Analysis The level statistics refer to the received signal level for a mobile: • Level (Full) Distribution (between -47 and -110) • Level (Sub) Distribution (between -47 and -110) • Cumulative Level Distribution • Level Banding
- 25. RxQual -Quality full and Sub distribution for both hopping and non- hopping samples -Cumulative Quality Distribution -Interference
- 26. Handover Analysis • Problem areas are automatically identified • Handover success/failure is shown on route • Position failure is located on XY graph • Cause/solution proposed for each failure • Step-by-step replay control allows every stage of handover to be broken down for detailed analysis • Forced Handover
- 27. Handover Stats • Handover Distribution - The number of Inter and intra cell handovers attempted, completed and failed • Handover Performance - Inter and intra cell success rate and the total HO success rate • Number of Handovers per call - The number of handovers that occurred per call within the testmobile survey.
- 28. Neighbour Analysis • The serving cells ID and full geographic location • The ID and full geographic location of the Neighbour cells that are either missing or have not been measured • Problem areas are separately displayed on the 2D map view
- 29. Call Analysis • Analysis of live calls, call success, signal levels and call quality can be done • Mean and worst call levels, quality, detailed comparative summary of cells signal strengths, analysis of sites
- 30. Call Statistics • Call Distribution - Evaluates every call and categorizes it as a Good Call or a No setup call • Call Holding Time - Displays the duration of each call. • Call Performance - Details for the Setup rate, Failure rate and Release rate. • Call Setup - Time Distribution Call Timers
- 31. Call Performance
- 32. Cell Statistics • Cell Domination • Cell poor Quality Distribution • Cell Average Quality Distribution • Cell Average Level Distribution • Cell Mean Call Holding Time • Cell average TA Distribution
- 33. Layer2 &Layer 3 Messages
- 34. Layer3 Information During Drive Test
- 35. DL RLC Throughput Vs DL RLC BLER
- 36. DL LLC Throughput (bytes/sec) vs DL RLC BLER
- 38. Neptune Features • State-of- the-art PC based optimization tool delivering real time analysis capabilities • User friendly with intuitive menu structure making it ideal for both real- time and post measurement analysis • Automatic fault finding and problem solving diagnostic capabilities • Live call analysis • Statistical and graphical display • Long and short term cost savings due to competitive pricing and the substantial shortening of the optimization process. • Supports additional testmobile formats, which can be loaded and analyzed
- 39. Test Mobile Import Facility • TEMS Investigator • TOM Measurement System • GPRS and HSCSD, Nemo technologies • GSM log files from X-PLOR ANT units
- 40. Probe • Has ability to perform time-based, operator based and distance based analysis • Statistics generated show the system’ s problems as a whole rather than pin- pointing each and every problem
- 41. Features • Ideal for both real-time and post measurement analysis • Displays a network’s Key Performance Indicators • Key Performance Indicators are combined to produce the Network Quality and Efficiency Factor • Statistical and graphical display • Long and short term cost savings due to competitive pricing and the substantial shortening of the optimization process • Flexible hardware option