1. Parameter Optimization

2. Review Parameter optimization is an important step after RF Optimization. Parameteroptimization improves service quality and utilization of network resources. 3. Review 4. Objectives Upon completion of this course, you can: Understand the process of parameteroptimization Master the contents of parameteroptimization 5. ContentsParameter optimization procedureParameter optimization contents 6. Parameter Optimization Process 7. Data Input and Find ProblemsFind problems from the input data, such as: Low success rate of call setup Low success rate of handover High rate of call drop 8. Verify Parameter Problems 9. Parameter Classification Mobile Management Parameters PowerControl Parameters PowerConfiguration Parameters LoadControl Parameters Other Parameters 10. Determine Parameter Values List the form for changing parameters(original parameter values vs. new parameter values) List MML commands for changing parametersNote: Maybe some tradeoff considerations need to be considered to assure the maximal improvement in the whole view such as coverage and capacity, fast and stable, improvement and risk, cost (or efforts) and gain. 11. Impact Impact on customer service and other networks Impact on OMC (efforts, maintenance) 12. Prepare Test Plan and Change Parameters Prepare test schedule, routes, tools and be ready to get Information. Changeparameters and make records. 13. Course ContentsParameter optimization ProcedureParameter optimization Contents 14. Parameter Optimization Contents Mobile Management parameter optimization PowerControl parameter optimization PowerConfiguration parameter optimization Load Control parameter optimizationNote:There are too many parameters to introduce. Only some parameters aboutnetwork optimization are mentioned here and maybe more parametersneed to be added in the future. 15. Mobile Management Parameter Optimization Cell Selection & ReselectionThe changing of cell on which UE camped in idle mode or in Cell FACH, CellPCH, URA PCH states. That assures UE camping the most suitable cell,receiving system information and establishing an RRC connection on a bestserving cell. HandoverThe changing of cells with which UE connected in DCH mode.That assures seamless coverage and load balancing. 16. Cell Selection & Reselection Procedurego here whenever a new PLMN is selectedcell informationno cell information stored for the PLMN1stored for the PLMNStored Initial information no suitable cell found Cell SelectionCell Selection no suitablecell foundsuitable cell found 2suitable cell foundno suitable cell foundCell SelectionNAS indicates thatwhen leavingsuitableCampedregistration on selected connectedcell foundnormally PLMN is rejectedmode(except with cause #14or #15 [5][16])return toleavetrigger idle modeidle modesuitablecell foundConnectedCellmodeReselectionno suitableEvaluationcell found Process go here when no USIM in the UE Any Cell no acceptable cell foundSelectionUSIM inserted acceptablecell found 1 Cell Selectionacceptable when leavingCamped onsuitable cell foundconnected any cell cell found 2 modereturn toleavetrigger idle modeidle mode acceptable cell found Connected mode Cell(Emergency Reselection no acceptable calls only) Evaluationcell foundProcess 17. Cell Selection Criteria (S Criteria)The cell selection criterion S is fulfilled when:for FDD cells: Srxlev > 0 AND Squal > 0for TDD cells: Srxlev > 0Where:Squal = Qqualmeas QqualminSrxlev = Qrxlevmeas - Qrxlevmin - Pcompensation When a UE wants to select a UMTS cell, the cell must satisfy S criterion. 18. Cell Selection Parameters 19. Cell Re-selection Measure Condition Use Squal for FDD cells and Srxlev for TDD for Sx 1. If Sx > Sintrasearch, UE need not perform intra-frequency measurements.If Sx Sintersearch, UE need not perform inter-frequency measurements.If Sx SsearchRAT m, UE need not perform measurements on cells of RATm".If Sx Tother_RAT + H/2 Tother_RAT : the inter-system handover decision threshold; Mother_RAT : the inter-system (GSM RSSI) measurement result received by RNC; CIO: Cell Individual Offset, which is the inter-system cell setting offset; H : refers to hysteresis, If the formula is met, a trigger-timer called TimeToTrigForSysHo will be started, and a handover decision will be made when the timer times out;Note: if the inter-system quality satisfies the following condition before the timer times out: Mother_RAT + CIO < Tother_RAT - H/2 The timer will be stopped, and RNC will go on waiting to receive the next inter-system measurement report. The length of the trigger-timer is called time-to-trigger. 36. Inter-system Handover Parameters 37. Parameter Optimization Contents Mobile Management parameter optimization PowerControl parameter optimization PowerConfiguration parameter optimization Load Control parameter optimization 38. Power Control parameter optimizationPowerControl Characteristics Minimize the interference in the network, thus improvecapacity and quality Maintain the link quality in uplink and downlink by adjustingthe powersMitigate the near far effect by providing minimum requiredpowerlevel for each connection Provides protection against shadowing and fast fading 39. Power Control Classification Open Loop Power ControlOpen loop power control is used to determine UEs initial uplink transmit power in PRACH andNodeBs initial downlink transmit power in DPDCH. It is used to set initial power reference values forpower control. Outer Loop power controlOuter loop power control is used to maintain the quality of communication at the level of bearerservice quality requirement, while using as low power as possible. Inner loop power control (also called fast closed loop power control)Inner loop power control is used to adjust UEs uplink / NodeBs downlink Dpch Power every one slotin accordance with TPC commands. Inner loop power control frequency is 1500Hz. 40. Open Loop Power Control - Uplink BCH PICH channel power BCH C PICH channel powerCUL interference leve UL interference leveConstant Value Constant ValueRACHRACHMeasure CPICH_RSCPMeasure CPICH_RSCPand determine the initialand determine the initialtransmitted powertransmitted powerPreamble_Initial_Power = Primary CPICH TX power - CPICH_RSCP+ UL interference + Constant Valuewhere Primary CPICH TX power, UL interference and Constant Value are broadcastedin the System Information and CPICH_RSCP is the measured value by UE 41. Open Loop Power Control - Downlink Determine the downlink initial power Determine the downlink initial power control control DCH DCH RACH reports the RACH reports the measured value measured value Measure CPICH Ec/I0 Measure CPICH Ec/I0 EbRE P= ( PCPICH /( c )cpich Ptotal ) Io W Io Where R is the user bit rate. W is the chip rate (3.84M). Pcpich is the Primary CPICH transmit power. Eb/Io is the downlink required Eb/Io value for a bearer service. (Ec/Io)cpich is measurement value reported by the UE.is downlink cell orthogonal factor. Ptotal is the current cells carrier transmit power measured at the NodeBand reported to the RNC. 42. Open Loop Power Control Parameters 43. Outer Loop Power Control M Macr o di ver si t yacr o di ver si t y com ni ngbi com ni ngbi Set SI R tt ar get Set S R ar getI S NR C D N R C Set SI R tt ar get Set S R ar getISet SI R S et S RItt ar get ar getOuter loop control is used to setting SirTarget (Signal to Interference Ratio Target) for inner loop power control. Itis divided into uplink outer loop power control and downlink outer loop power control.The uplink outer loop power control is controlled by SRNC (serving RNC) for setting a target SIR for each UE. Thistarget SIR is updated according to the estimated uplink quality (Block Error Ratio/ Bit Error Ratio).If UE is not in DTX (Discontinuous Transmission)status (that means RNC can receive uplink traffic data),RNC will use Bler (Block Error Ratio) to compute SirTarget . Otherwise, RNC will use Ber (Bit Error Ratio) tocompute SirTarget.The downlink outer loop power control is controlled by the UE receiver to converge to required link quality (BLER)set by the network (RNC) in downlink. 44. Outer Loop Power Control Parameters 45. Inner Loop Power ControlThe inner loop power control adjusts the UE or NodeB transmitpower in order to keep the received signal-to-interference ratio(SIR) at a given SIR target, SIRtarget.It is also divided into uplink inner loop power control anddownlink inner loop power control. 46. Uplink Inner Loop Power Control UTRAN behaviourThe serving cells (cells in the active set) should estimate signal-to-interference ratioSIRest of the received uplink DPCH. The serving cells should then generate TPCcommands and transmit the commands once per slot according to the following rule: ifSIRest > SIRtarget then the TPC command to transmit is "0", while if SIRest < SIRtargetthen the TPC command to transmit is "1". UE behaviourUpon reception of one or more TPC commands in a slot, the UE shall derive a single TPCcommand, TPC_cmd, for each slot, combining multiple TPC commands if more than oneis received in a slot. This is also valid when SSDT transmission is used in the downlink.Two algorithms shall be supported by the UE for deriving a TPC_cmd. Which of thesetwo algorithms is used is determined by a UE-specific higher-layer parameter,"PowerControlAlgorithm",andis under thecontrol of the UTRAN. If"PowerControlAlgorithm" indicates "algorithm1", then the layer 1 parameter PCA shalltake the value 1 and if "PowerControlAlgorithm" indicates "algorithm2" then PCA shalltake the value 2. 47. Uplink Inner Loop Power Control The step size DTPC is a layer 1 parameter which is derived from the UE-specific higher-layer parameter "TPC-StepSize" which is under the control of the UTRAN. If "TPC-StepSize" has the value "dB1", then the layer 1 parameter DTPC shall take the value1 dB and if "TPC-StepSize" has the value "dB2", then DTPC shall take the value 2 dB.The parameter "TPC-StepSize" only applies to Algorithm 1 . For Algorithm 2 DTPC shallalways take the value 1 dB. After deriving of the combined TPC command TPC_cmd using one of the two supportedalgorithms, the UE shall adjust the transmit power of the uplink DPCCH with a step ofDDPCCH (in dB) which is given by:DDPCCH = DTPC TPC_cmd. 48. Uplink Inner Loop Power Control Algorithm 1 for processing TPC commands When a UE is not in soft handover, only one TPC command will be received in each slot. In this case, the value of TPC_cmd shall be derived as follows: - If the received TPC command is equal to 0 then TPC_cmd for that slot is 1. - If the received TPC command is equal to 1, then TPC_cmd for that slot is Algorithm 2 for processing TPC commands When a UE is not in soft handover, only one TPC command will be received in each slot. In this case, the UE shall process received TPC commands on a 5-slot cycle, where the sets of 5 slots shall be aligned to the frame boundaries and there shall be no overlap between each set of 5 slots. The value of TPC_cmd shall be derived as follows: - For the first 4 slots of a set, TPC_cmd = 0. -For the fifth slot of a set, the UE uses hard decisions on each of the 5 received TPC commands as follows: If all 5 hard decisions within a set are 1 then TPC_cmd = 1 in the 5th slot. If all 5 hard decisions within a set are 0 then TPC_cmd = -1 in the 5th slot. Otherwise, TPC_cmd = 0 in the 5th slot. 49. Downlink Inner Loop Power Control UE behaviour The UE shall generate TPC commands to control the network transmit power and send them in the TPC field of the uplink DPCCH. The UE shall check the downlink power control mode (DPC_MODE) before generating the TPC command: If DPC_MODE = 0 : the UE sends a unique TPC command in each slot and the TPC command generated is transmitted in the first available TPC field in the uplink DPCCH; If DPC_MODE = 1 : the UE repeats the same TPC command over 3 slots and the new TPC command is transmitted such that there is a new command at the beginning of the frame. The DPC_MODE parameter is a UE specific parameter controlled by the UTRAN. 50. Downlink Inner Loop Power Control UTRANbehaviour Upon receiving the TPC commands UTRAN shall adjust its downlink DPCCH/DPDCH power accordingly. For DPC_MODE = 0, UTRAN shall estimate the transmitted TPC command TPCest to be 0 or 1, and shall update the power every slot. If DPC_MODE = 1, UTRAN shall estimate the transmitted TPC command TPCest over three slots to be 0 or 1, and shall update the power every three slots. 51. Inner Loop Power Control Parameters 52. Parameter Optimization Contents Mobile Management parameter optimization PowerControl parameter optimization PowerConfiguration parameter optimization Load Control parameter optimization 53. Physical Channels Types 54. Common Channel ParametersAll channels power refers to PCPICH power expect PCPICH. 55. Dedicated Channel ParametersDedicated Channel Power refers to PCPICH Power. 56. Parameter Optimization Contents Mobile Management parameter optimization PowerControl parameter optimization PowerConfiguration parameter optimization Load Control parameter optimization 57. Load Control Parameter OptimizationCall Admission Control (CAC) Call admission control is used to control cells load byadmission/rejection request to assure a cells load under control. Dynamic Channel Configuration Control (DCCC) Dynamic Channel Configuration Control is used to dynamicallychange a connections load to improve cell resource utilizationand control cells load. 58. Call Admission Control Procedure 59. Call Admission Control ParametersDifferent service type can be configured different threshold. That means leave someresources for important service ( or request), such as HO > Conversation > Other.Ul(Dl)TotolKThd is used when NodeB load report is not available . It uses equivalent12.2k-voice users number method. 60. Dynamic Channel Configuration Control Dynamic channel configuration control (DCCC) aims to make full useof radio resource (codes, power, CE )- Configured bandwidth is fixed with no DCCC Rate or band- Configured bandwidth is changing with DCCC- Traffic rate 61. DCCC ProcedureTraffic Volume measurement control UE and RNC Measurement Measurement reportDCCC decision DCCC execution 62. Traffic Volume Measurement Transport ChannelTrafficVolume ThresholdTime ReportingReporting event 4A event 4ATransportChannel Traffic VolumeThresholdTimeReportingReportingReportingevent 4B event 4B event 4B 63. DCCC Decision1) 4a event report -> increase bandwidth 4b event report -> decrease bandwidth2) if current bandwidth