2RF Planning and Drive Test Tools of 2G.3G.4G and 5G

• GSM (2G) Drive Test Parameters

  • Rx level: Received signal strength in dBm
  • Rx Quality: Quality of voice, measured on BER (0-7, 0 is minimum BER)
  • C/I: Carrier-over-interference ratio, ratio of serving cell signal strength to interfering signal strength (in dB)
  • FER: Frame Erasure Rate, percentage of frames dropped due to high bit errors, indicates voice quality
• CPICH EC/NO


  Chip Energy by Noise- Ratio of energy of the chip and combined power of all signals including the pilot channel. Indicates noise disrupting the pilot channel. Ranges: 0 to -7 Good, -7 to -10 Acceptable, -10 to -36 Bad
• CPICH RSCP


  Received Signal Code Power, total power of the entire cell or specific pilot channel received by the user equipment. Ranges: -30 to -75 Good, -75 to -85 Acceptable, -85 to -140 Bad
• TX Power


  Transmitting power of the mobile station, varies from 50 to -50. Lower Tx power is better for call quality.
• RSSI


  Received Signal Strength Indicator, total power of the entire common pilot channel received by the mobile station, including interference and noise. RSSI = RSCP + Ec/No. Ranges: 0 to -75 Good, -75 to -85 Acceptable, -85 to -140 Bad
• SIR


  Signal to Interference ratio, ratio of energy in the dedicated physical control channel to interference and noise received by the user equipment
• SQI


  Speech Quality Index, parameter to rate voice quality on a call, ranges from 0 to 30 with 30 being best. AMR (Adaptive Multi Rate) is used to enhance voice quality.
• RRC State


  Indicates the current state and channel, whether idle or dedicated
• Cell Name


  Specific name of the Node B assigned by the operator based on location and serial value
• Scrambling Codes


  Used to identify different cells of a Node B. Primary Scrambling Codes (0-511) identify different sectors, Secondary Scrambling Codes are used in beamforming.
• Active Set


  Set of scrambling codes the user equipment is currently connected to, maximum 3
• Monitored Neighbor


  Neighbor cell detected by user equipment as a neighbor
• Detected Neighbor


  Cells detected by user equipment that are neither in the active set nor monitored set. Indicates missing neighbors, can cause call drops.
• RSCP


  Received Signal Code Power, shows the signal strength of a cell, indicates coverage
• RSSI


  Received Signal Strength Indicator, total signal strength of a UTRA carrier frequency
• Ec/No


  Received energy per chip divided by power density, shows signal quality. Good: >-15dB, Poor: -15dB to -18dB, Very Poor: <-18dB
• Active, Monitored and Detected Sets

  Active Set: Cells the UE is connected to

  Monitored Set: Cells not in active set but probable handover candidates

  Detected Set: Cells detected by UE but not in active or monitored sets, can cause interference
• Pilot Pollution


  When the number of strong cells exceeds the active set size, causing interference and degrading Ec/No
• Radio Network Optimization LTE using Drive Test

  Collect statistics and KPIs from network management system

  Perform drive tests to measure coverage, capacity and quality

  Analyze statistics and drive test data to identify problems

  Apply corrective actions like site re-engineering, frequency planning review

  Optimize KPIs like Call Setup Success Rate and Drop Call Rate
• Drive Test


  Method of measuring and assessing coverage, capacity and quality of service of a mobile radio network, used in planning and optimization stages
• Correct site re-engineering


  • It is the basis for a good performing network
  • Frequency planning review is also a key step in the process
• Network planning optimization


  1. Various operations

  2. Leading to the improvement of KPIs
• Input data for starting optimization

  KPI values in a certain area
• Area KPI is greater or less than the target

  Troubleshooting on a cell basis starts
• Statistics


  Can be extracted weekly, daily or even on an hourly basis from the NMS
• Call Setup Success Rate (CSSR)


  One of the main KPIs relevant to operator losses
• Dropcall rate (DCR)


  One of the main KPIs relevant to operator losses
• Drive Testing


  A method of measuring and assessing the coverage, capacity and Quality of Service (QoS) of a mobile radio network
• Drive Testing


  • Principally applied in both the planning and optimization stage of network development
  • Drive tests are the most common measurement tool used by operators, to probe the quality status and solve network problems
• Drive Testing technique


  1. Using a motor vehicle containing mobile radio network air interface measurement equipment

  2. Can detect and record a wide variety of the physical and virtual parameters of mobile cellular service in a given geographical area
• Drive test tool


  Used for checking the coverage criteria of the cell site with the RF drive test
• Log files


  Data collected by drive test tool, assessed to evaluate the various RF parameters of the network
• Data acquired from drive test

  • Signal intensity
  • Signal quality
  • Interference
  • Dropped calls
  • Blocked calls
  • Call statistics
  • Service level statistics
  • QoS information
  • Handover information
  • Neighbouring cell information
  • GPS location co-ordinates
• Types of drive testing

  • Network Benchmarking
  • Optimization & Troubleshooting
  • Service Quality Monitoring
• Network Benchmarking


  Sophisticated multi-channel tools are used to measure several network technologies and service types simultaneously to very high accuracy and collect accurate competitive data on the true level of their own and their competitors technical performance and quality levels
• Optimization & Troubleshooting


  Information is more typically used to aid in finding specific problems during the rollout phases of new networks or to observe specific problems reported by consumers during the operational phase of the network lifecycle
• Service Quality Monitoring


  Involves making test calls across the network to a fixed test unit to assess the relative quality of various services using Mean opinion score (MOS)
• Drive test equipment


  • Laptop
  • Drive Test software with Dongle/License Key
  • GPS (Global Positioning system) to provide location information
  • One or Multiple Handsets Compatible with the Drive Test Software
  • Scanner (Optional)
  • Database of Existing Network (Cell site database)
  • A Suitable Vehicle
• All the equipments (GPS, Mobile Handsets, Dongle) are connected to Laptop via USB ports
• Data Collection Tools


  • TEMS Investigation
  • Nemo Outdoor
  • JDSU E6474A
  • Accuver XCAL