3G Ericsson 3G Ericsson Optimization and Planning’s Concepts, Commands, and Case Studies Improve your Experience as a Senior 3G Optimization Engineer Based on my experience as an RF optimization engineer, this data has been collected for a couple of years, and it has been grown step by step. The last update was about 2017, but I think it is valuable to share for someone who wants to improve his/her experience in 3G RF optimization to the senior level. Or, someone who is going to plan for an interview. These used cases have been implemented in a live Ericsson Network, but most of them are common in different vendors. It includes: • 3G Fundamental • Features implementation results and suitable parameters' value • Optimization Activities’ result • Important and useful tools: • • • WNCS: WCDMA Neighboring Cell Support MRR-W: Measurement Result Recording for WCDMA FFAx-W: Find Faulty Antenna Expert for WCDMA Mohammad Rasoul Tanhatalab RAN Performance and Optimization Specialist and Data Scientist I have hands-on experience in Mobile RAN Performance and Optimization areas for over 10 years. Besides, I am passionate about Machine Learning and Data Science techniques with 5+ of experience. I have 5 stars rank on HackerRank.com as a senior Python developer, furthermore, proficient knowledge in AI, Machine Learning, Tensorflow, Deep Learning, Statistics, Mathematics, and Analytics. And, I have published over 18 papers in International conferences. For More Information: www.sam-set.com WhatsApp: +989022700760 Conducted Projects on 3G Throughput https://ieeexplore.ieee.org/document/7967048 https://ieeexplore.ieee.org/document/8250037 WCDMA RAN Optimization activity • Consistency Check Parameters Neighbor definition • • Statistics • • Alarms • • Cell Availability • RRC Establishment RAB Establishment • • • • CS DCR PS DCR RRC Drop Rate RAB Drop Rate Call Setup Success Rate PS setup success rate (EUL, HSDPA, R99) • BLER /BER • Throughput • • • • • HO performance Neighbor Relations SHO/ISHO Success Rate SHO Overhead HDSPA/HSUPA SCC success rate Retainability The probability that a service, once obtained, will continue to be provided under given conditions for a given time duration. The percentage of the successfully call setups that were retained during the whole conversation (session) and terminated by the user. The standard KPI for retainability is the Dropped Call Rate. On cell level it is defined as the number of dropped calls in the cell divided by the total number of calls terminated (by enduser or dropped) in the cell. Integrity The degree to which a service is provided without excessive impairments, once obtained The Service Integrity represents the quality experienced by the user during the call or session. This is very difficult to measure from a system point-of-view and rough measures have to be used, based on RBS and UE measurements. BLER is used as an indication of the service integrity for CS services, but do not show the quality experienced by the end-user. For PS services are BLER and throughput used as service quality indicators. Accessibility The ability of a service to be obtained, within specified tolerances and other given conditions, when requested by the user. It is the percentage of call attempts made by the end-user that are successful. Call setup failures can be blocked calls due to lack of network resources on various levels, for example Transmission Network, Channel Elements, DL Power and so on, or other reason that prevented a successful call setup, for example radio link problem, signaling failure and so on. Mobile Call Setup • UE IN IDLE MODE – – – – – • PLMN SELECTION CELL SELECTION LA AND RA UPDATE PAGING SYSTEM INFORMATION RANDOM ACCESS – UL OPEN LOOP POWER CONTROL • RRC CONNECTION SETUP – – – – – – • EMERGENCY CALLS MODULE MP LOAD ADMISSION CONTROL BLOCK LACK OF TRANSMISSION RESOURCES LOAD SHARING RADIO LINK SETUP NAS PROCEDURES – CM SERVICE REJECT • RADIO BEARER SETUP – UE CELL RESELECTION DURING HANDOVER – UE CELL RESELECTION RRC CONNECTION SETUP Random Access Procedure Connection established with minimum interference to other users Dedicated channel at just enough power UE 1 1) UE2 measures Pilot channel 2) UE2 Reads interference level from Broadcast channel The power is ramped up until a response is heard or maximum number of re-attempts is reached UE 2 RBS What is the main difference between 3G and 2G Ec/No, RSCP and RSSI Ec/No signifies the level difference between received pilot signal and the overall noise floor. No is the noise floor, which signifies all the signals (useful and interfering) present at the receiver side. For example: A value of Ec/No= -8dB tells us that the spread signal is 8 dB below the noise floor RSCP : Received Signal Code Power is the received power on one code after dispreading, defined on the pilot symbols. Ec/No = RSCP/RSSI RSSI It is the combination of all signals received on the downlink frequency ( in FDD mode ) of the WCDMA system. As such it is also referred to as the total noise on the downlink . It is the equivalent of RTWP on the uplink. RSSI : Includes all components received. Including the signals from the current and neighbors on the same frequency What is the difference between Scrambling, Spreading and Channelization Codes Spreading Code = Channelization Code Chip rate is consistence and is 3.84 Mcps then we need the 3.84 MHz Cell breathing phenomena PS and CS traffic pmDlTrafficVolumePsCommon: Payload traffic in the downlink for the PS RAB on FACH, excluding SRB Erlang_PKT Vs. Elang_Speech ERLANG_PKT_HS (PMSUMBESTPSHSADCHRABESTABLISH / 720) Sum of all sample values recorded during a ROP for the number of A-DCH radio bearers established in the caell carrying HS-DSCH in the active set. Condition: Values are read periodically from an internal level counter and added to this counter. The level counter maintains the current number of A-DCH radio bearers established in the cell carrying HS-DSCH in the active set for which this cell is the best cell. Erlang_3G_Speech nvl(pmSumBestCs12Establish,0) / (3600/5)+ nvl(PMSUMBESTAMR12200RABESTABLISH,0) / (3600/5)+ nvl(PMSUMBESTAMR4750RABESTABLISH,0) / (3600/5)+ nvl(PMSUMBESTAMR5900RABESTABLISH,0) /(3600/5) + nvl(PMSUMBESTAMR7950RABESTABLISH,0) /(3600/5) DATA COLLECTION Performance Statistics are continuously collected from all Network Elements (NE) and stored persistently in Operation Support System, Radio and Core (OSS-RC). Statistics are mainly used for the detection of problem areas and for monitoring the performance of the network on a daily basis. The complete WCDMA Radio Access Network (RAN)Performance Management (PM) functionality receives support from all WCDMA RAN nodes: • Radio Base Station (RBS) • Radio Network Controller (RNC) • Radio Access Network Aggregator (RANAG – RXI) • OSS-RC. The traffic nodes provide the performance information through a file interface. This information is collected by OSS-RC. HSPA Air interface 3G Air interface 3G Channels Manage Object Overview An MO represents a resource in the node, either a physical resource such as a plug-in unit or a logical resource such as a software program or a protocol. In either case, there are parameters associated with the resource, called MO attributes SRNC, DRNC, RAB, RB and RL SRNC and DRNC SRNC and DRNC are concepts for a connected UE. The SRNC handles the connection to one UE, and may borrow radio resources of a certain cell from the DRNC. Drift RNCs support the Serving RNC by providing radio resources A UE in connection state has at least one and only one SRNC, but can has 0 or multiple DRNCs RAB, RB and RL in WCDMA RAB: The service that the access stratum provides to the non-access stratum for transfer of user data between User Equipment and CN. RB: The service provided by the layer2 for transfer of user data between User Equipment and Serving RNC. RL: A “radio link” is a logical association between single User Equipment and a single UTRAN access point. Its physical realization comprises one or more radio bearer transmissions. PM prefix Random Access Parameters • • The Random Access Procedure is utilized by the UE to access the UTRAN network from an Idle, or Cell_FACH state Check RACH parameters to look for a wrong setting: • • • • • • • aichPower powerOffsetP0 powerOffsetPpm preambleRetransMax maxPreambleCycle constantValueCprach maxTxPowerUl Admission control Admission control is used in both the uplink and downlink. The admission decision is based on air interface load, by using measurements of uplink interference, downlink output power as well as the actual number of users. There are nine admission policies to control the blocking. 1. 2. 3. 4. 5. 6. 7. 8. 9. UL ASE DL ASE DL TX cell power spreading factor usage code usage HW usage amount of HS users congestion number of users in compressed mode Admission Control has different policies The counter pmNoReqDeniedAdm shows the number of RRC establishment requests and RAB establishment requests denied for a cell. Please note that this counter is stepped up for RRC establishment, RAB establishment or channel up-switching if admission control triggers the blocking in a cell. The solution to the admission control blocking problem is to check if the admission thresholds (i.e. ulHwAdm, hsdpaUsersAdm , maximumTransmissionPower, aseUlAdmOffset, beMarginAseDl, beMarginAseUl, beMarginDlCode, compModeAdm, dlCodeAdm) match to the original planned capacity. If the thresholds do not match to the original planned capacity, the admission thresholds have to be corrected. Otherwise, re-do the radio network dimensioning to increase the system capacity or activate the inter-frequency load sharing to increase the trucking efficiency. RRC Connection Request/Setup RRC:RACH/CCCH : RRC Connection Request RRC:FACH/CCCH : RRC Connection Setup • FACH1 is used to carry control information • Parameter maxFach1Power [-35.0..+15.0] dB • Increasing the power of FACH1 will have higher probability to receive RRC Connection Setup especially in low coverage areas. Change maxFach1Power from 18 to 38 (1.8 dB 3.8 dB) Notes: this setting is not recommended for high capacity cells Pilot Pollution • When the number of strong cells exceeds the Active Set Size (How many Cells can be on Soft Handover with a UE), There becomes pilot pollution in the area. • Typically the active set size is 3, so if there are more than 3 strong cells then there is pilot pollution. • Definition of “strong cell”: pilots within the handover window size from the strongest cell. Typical handover window size is between 4 to 6dB. (Depends generally Event1b Removal Range) • For example, if there are more than 2 cells (besides Active Set Cells) within 5dB of the strongest cell then there is pilot pollution. • The UE has the ability to constructively use signals in soft/softer handover, all the other signals received that exceeds the Active Set act as interfering. This interference degrades the performance of the system. Call Setup Failure Analysis Process__DT The on-Air site did not define in OSS find by O&M IP Resources to be monitored • RF Power – Lack of Downlink Power (pmNoFailedRabEstAttemptLackDlPwr) • Code Tree Consumption – Lack of Canalization Code (pmNoFailedRabEstAttemptLackDlChnlCode) • RRC level code – Lack of Canalization Code (pmNoRrcreqdeniedAdmDlChanlCode) • DL and UL ASE – Lack of Downlink ASE (pmNoFailedRabEstAttemptLackDlAse) – Lack of Uplink ASE (pmNoFailedRabEstAttemptLackUlAse) • SF Code Limit (Code Hystogram) – Exceed SF histogram (pmNoFailedRabEstAttemptExceedConnLimit) • HSDPA and EUL connections Limit • UL and DL Channel Elements (CE) – Lack of DL Channel Elements (pmNoFailedRabEstAttemptLackDlHw) – Lack of UL Channel Elements (pmNoFailedRabEstAttemptLackUlHw) Power Congestion (RRC Denied) pmNoRrcReqDeniedAdm Number of RRC requests denied by admission control. The counter is trigged when an RRC connection request with any cause value is denied by Admission Control pmNoRrcReqDeniedAdmDlPwr Number of RRC Connection Requests denied by admission control due to lack of DL Power. Power Congestion (RAB attempt failed) pmNoFailedRabEstAttemptLackDlPwr Number of RAB establishment attempts that failed due to lack of downlink power. PWR congestion due to locked third carrier configurations Congestion Issue pmNoOfSwDownNgAdm Number of downswitch requests for nonguaranteed and guaranteed-hs users served by this RNC due to admission control Condition: Incremented by one when downswitching from Cell_DCH 64/384->64/128 or Cell_DCH 64/128->64/64 initiated by admission control to do Best Effort Cleanup. This is done after an admission rejection due to insufficient downlink power or code utilization limits. The connection to switch down is selected if it is a non-guaranteed and non-drifting connection with a lower spreading factor than that of the latest requested radio link. The counter is incremented in the cell which had to reject admission. Idle Behavior (2G and 3G) Parameters QSI (Quality Search Index) and QSC define thresholds and indicate when UTRAN measurements shall be performed (for start of UTRAN FDD measurements in idle mode). QSI is used for idle and packet switched modes and broadcast on BCCH, while QSC is used for active mode, sent on SACCH. It is better to finish the CS call first and then do the IRAT cell reselection. For (0-6) the UE searches for UTRAN cells if the signal level is below the threshold. For (8-14) for above the threshold 2G Command: rlsup:cell=“cell-name”; Feature activation in BSC The feature GSM-UMTS Cell Reselection and Handover is activated per BSC with the exchange property COEXUMTS. COEXUMTS is used to enable the features GSM-UMTS Cell Reselection and Handover, Combined Cell Reselection Triggering and Combined Handover Triggering GSM to WCDMA. The parameter is a BSC exchange property. – 0 OFF ; GSM-UMTS Cell Reselection and Handover and Combined Cell Reselection Triggering GSM to WCDMA are not activated. – 1 ON; GSM-UMTS Cell Reselection and Handover is activated. – 2 ONADDINFO; GSM-UMTS Cell Reselection and Handover and Combined Cell Reselection Triggering GSM to WCDMA are activated – 3 ONADDINFO; GSM-UMTS Cell Reselection and Handover and Combined Handover Triggering GSM to WCDMA are activated – 4 ONADDINFO; GSM-UMTS Cell Reselection and Handover, Combined Cell Reselection Triggering GSM to WCDMA and Combined Handover Triggering GSM to WCDMA are activated • BSC Command: raepp:ID=all; 2G to 3G cell reselection based on cell Ranking The algorithm for cell reselection to UMTS is controlled by the network with the parameters FDDQMIN and FDDQOFF • A Multi-RAT capable UE will reselect a suitable UTRAN cell if the following criteria are fulfilled : – CPICH Ec/No > FDDQMIN & – CPICH RSCP > RLA(s+n) + FDDQOFF – for a period of 5 seconds. (RLA(s+n) = Received Level Average of serving and neighboring GSM cells) 3G CELL SELECTION The UE bases its evaluation on two quantities: Squal and Srxlev. The cell selection criteria are fulfilled when: – Squal = Qqualmeas- qQualMin > 0 – Srxlev = Qrxlevmeas – qRxLevMin – Pcompensation > 0 Where Pcompensation = max(maxTxPowerul – P;0) • • • qQualmin and qRxLevMin is sent in the broadcast information (SIB 3 for serving cell and SIB 11 for adjacent cells) maxTxPowerUl is the maximum transmission power during random access on the RACH and that value is sent in the system information (SIB 3). P is the UE maximum output power according to its class. The UE measures the received signal Code Power (CPICH RSCP) and the received quality, on the CPICH (CPICH Ec/No) obtains Srxlev and Srxlev. If both criteria are fulfilled and other requirements for a suitable cell are fulfilled the UE will camp on the cell. The UE will enter the state “camped normally” where it performs intra-, inter- and intersystem radio measurements to evaluate if a neighboring cell is better than the serving one. CHANNEL SWITCHING Channel Switching Fundamental Each channel (FACH/RACH/DCH) requires resources that are “fixed” allocated to that channel (such as DL channelization codes, RBS hardware, RAKE receivers, coding processors etc). Regardless if the channel is used or not the resources allocated to that channel cannot be used by another channel. In the RNC each user has resources allocated but the most limiting resources are the air interface resources (interference/power and the RBS hardware) so it is important to optimize the usage of these as much as possible. • The logical channels, DCCH and DTCH, are mapped onto the DCHs and further onto Dedicated Physical Channels. These physical channels use inner-loop power control. • In the common state the UE is able to transmit control signals and data packets on the common transport channel RACH. The UE also monitors the FACH to receive downlink information. The logical channels, DCCH, CCCH, and DTCH are mapped onto the RACH and the FACH. These channels are suitable for carrying common control information and are shared by all users in the cell. A maximum of 32 kbit/s is available for user data transmission. Best Effort (BE) users are handled by ‘Channel Switching’ in the WCDMA RAN. Both channel type and channel rate switching are supported. The channel type switching is based on throughput and buffer sizes. The rate switching can be triggered by Admission control, Soft Handover and coverage reasons There are 8 types of channel switching: 1. 2. 3. 4. 5. 6. 7. 8. RBS Capacity will calculate with Cell_DCH Users Common to Dedicated Evaluation Dedicated to Common Evaluation DCH-DCH Up-Switch Evaluation DCH-DCH Down-Switch Evaluation Common to Idle Evaluation Multi-RAB Up-switch Evaluation Multi-RAB Down-switch Evaluation Down switch: Handover Based • Cell_DCH State – – – – – – • Cell_FACH State – – – – • No dedicated physical channel is allocated to the UE. The UE continuously monitors a FACH in the downlink. The UE is assigned a default common or shared transport channel in the uplink (RACH or CPCH) that it can use anytime according to the access procedure for that transport channel. The position of the UE is known by UTRAN on cell level according to the cell where the UE last made a cell update. Cell_PCH – – – – – • A dedicated physical channel is allocated to the UE in uplink and downlink. The UE is known on cell level according to its current active set. Dedicated transport channels, downlink and uplink (TDD) shared transport channels, and a combination of these transport channels can be used by the UE. The Cell_DCH state is entered from the Idle Mode through the setup of an RRC connection, or by establishing a dedicated physical channel from the Cell_FACH state. No dedicated physical channel is allocated to the UE. The UE uses DRX for monitoring the selected PCH via an associated PICH. No uplink activity is possible. The position of the UE is known by UTRAN on cell level according to the cell where the UE last made a cell update in Cell_FACH state. URA_PCH – – – – No dedicated channel is allocated to the UE. No uplink activity is possible. The location of the UE is known on UTRAN Registration Area (URA) level according to the URA assigned to the UE during the last URA update in Cell_FACH state. If the network wants to initiate any activity, it needs to make a paging request on the PCCH logical channel within the URA where the location of the UE is known. Power Control Why the WCDMA use Power Control: • Minimize the UL-Interference • Minimize the DL Transmit Power • Share resource in WCDMA • Keeping connection quality • Compensating channel destructive effects like attenuation, fading .. • Battery life time improvement in UE WCDMA Power Control loops working together (UE example) Power Control Setting Common Channel Powers Sharing Power Pilot Channel Power • • • • • • primary CPICH power should be 8 to 10% (~ 1 Watt) of the nominal RBS power at the reference point (~10W, while MCPA is 20W) The pilot power is designed to be equal in all cells at the Reference Point. – primaryCpichPower = 30 dBm – TopOfRack = primaryCpichPower + dlAttenuation System will adjust the TopOfRack to meet the required value. Consistency check on MaximumTransmissionPowerDL (Calculated vs. setting value) The feeder loss parameters ulAttenuation & dlAttenuation and electrical delay parameters ulElectricalDelay & dlElectricalDelay must be entered properly in the system (actual VSWR). More CPICH – less capacity trade off P-CPICH dl/ulAttenuation dl/ElectDelay TopOfRack set UtranCell=9546XA primarycpichpower 330 MaxTxPowerDL To see Max DL Power Capability Carrier maxDlPowerCapability long readOnly,nonPersistent -----------------------------------------------------------------------------------------------------------------------------------The maximum downlink power capability for the carrier. Unit: 0.1 dBm Undefined value: -1 Range: -1 to 500 ************************************************************************************************************************************ RbsLocalCell maxDlPowerCapability long readOnly,nonPersistent -----------------------------------------------------------------------------------------------------------------------------------The maximum downlink power capability for the cell. For a cell using more than one carrier, this value is the maximum DL power capability among the carriers. The attribute value is reported to the RNC. Unit: 0.1 dBm Undefined value: -1 Specification: 3GPP TS 25.433, NBAP, UTRAN Iub interface NBAP signalling Range: -1 to 500 To see Antenna Feeder Capability CPICH power • Dependencies: Effect of Change: Change of this parameter effects pilot coverage e.r. handover areas, interference areas, traffic coverage areas. Too low value can lead to appearance of “coverage holes”. Too high value can lead to “near–far” effect or that cell is taking too much traffic. In the loaded co-sited network it can be that some problems we will be solving changing this parameter. • Troubleshooting: This parameter should be investigated when the following problems are observed : Pilot Channel failure due to high downlink interference ( Possible causes: No dominant cell, Dominant interferer, Low best serving EcIo); Pilot Channel failure – out of pilot coverage (Possible causes: Low pilot channel power); Pilot pollution (Possible causes: No dominant cell); Uplink and Coverage pilot imbalance ( Possible causes: Large pilot power, UE in compressed mode); Uneven load distribution (Possible cause: Homogenous pilot setting in an irregular network), Random access procedure problem (Possible cause: PRACH and Pilot coverage imbalance) Handover Common Control Channel Power • • With increasing CPICH power – capacity directly decreasis, but common channels and power per each dedicated channel is calculated from CPICH At CPICH 30 dBm, the common channel will be configured as follow: Parameter Name primaryCpichPower MO Type UtranCell pchPower Pch primarySchPower Value Cumm(dBm) Peak Power(W) Typical AF Avg Power(W) 30 1 1 1 -0.4 29.6 0.91 0.20 0.18 UtranCell -1.8 28.2 0.66 0.10 0.07 secondarySchPower UtranCell -3.5 26.5 0.45 0.10 0.04 maxFach1Power Fach 1.8 31.8 1.51 0.10 0.15 maxFach2Power Fach 1.5 31.5 1.41 0.30 0.42 bchPower UtranCell -3.1 26.9 0.49 0.90 0.44 aichPower Rach -6 24 0.25 0.10 0.03 pichPower Pch -7 23 0.20 1.00 0.20 38.38 6.89 MaximumTransmissionPowerDL is design to be equal with Nominal RBS Power 2.53 Common Channel on Downlink Cell Setup and Reconfiguration - Downlink primaryCpichPower is the power used for transmitting the PCPICH. bchPower is the power used for transmitting on the BCH, relative to the primaryCpichPower value. primarySchPower is the power used for transmitting on the Primary SCH, relative to the primaryCpichPower value. secondarySchPower is the power used for transmitting on the Secondary SCH, relative to the primaryCpichPower value. Common Transport Channel Setup and Reconfiguration - Downlink aichPower is the power used for transmitting on AICH, relative to the primaryCpichPower value. maxFach1Power defines the maximum power used for transmitting the first FACH channel, relative to the primaryCpichPower value. The first FACH is used for logical channels BCCH, CCCH, and DCCH control signaling. maxFach2Power defines the Maximum power used for transmitting the second FACH channel, relative to the primaryCpichPower value. The second FACH is used for logical channel DTCH traffic signaling. pOffset1Fach is the offset between downlink DPDCH and DPCCH TFCI field on FACH. pOffset3Fach is the offset between downlink DPDCH and DPCCH pilot field on FACH. pchPower is the power used for transmitting on the PCH, relative to the primaryCpichPower value. pichPower is the power used for transmitting on the PICH, relative to the primaryCpichPower value. Common Channel on Uplink Common Transport Channel Setup and Reconfiguration - Uplink constantValueCprach is a constant value in dB used by the UE to calculate the initial power on the PRACH according to the Open Loop Power Control procedure. powerOffsetP0 is the Power ramp step for the preamble when no acquisition indicator is received. powerOffsetPpm is the Power offset between the last transmitted preamble and the control part of the random access message. preambleRetransMax is the maximum number of preambles sent in one RACH preamble ramping cycle. maxPreambleCycle is the maximum number of preamble ramping cycle. Preamble Power P_RACH The initial power on the PRACH - the power of the first preamble - is determined according to equation P_PRACH = L_PCPICH + RTWP + constantValueCprach (-27dB) Received Total Wideband Power (RTWP) All transmissions in the uplink contribute to the increase in uplink noise, or Received Total Wideband Power (RTWP). To limit the interference a UE can create, the parameter maxTxPwrUl is used to control the maximum power the UE can transmit. This parameter is typically configured to be 24 dBm for a Class 3 UE. L_PCPICH : is the path loss estimated by the UE based on knowing the transmitted and received PCPICH power. RTWP : is the Received Total Wideband Power (uplink interference) level measured by the RBS. constantValueCpra ch : is used by the UE to calculate the initial power on the PRACH . This parameter is configurable and decides at which level below RTWP preamble ramping will start POWER RAMP ON RACH To reach an appropriate received power level at the RBS, the UE uses preamble ramping. This procedure consists of the following steps: • The UE transmits a preamble. • As soon as the RBS properly detects the preamble, it sends an Acknowledgement Indicator (AI) on the AICH. • While not receiving any AI, the UE transmits a new preamble, increasing the transmission power with respect to the previous one by the configurable parameter powerOffsetP0.(3dB) • As soon as the UE receives an AI, it sends the PRACH message part. The power of the control part of the random access message is determined by the power of the last transmitted preamble and by a configurable offset powerOffsetPpm.(- 4dB) The power of the data part of the PRACH message is determined by the gain factors for PRACH, which is included in System Information. Common Channel on Uplink POWER RAMP ON RACH preambleRetransMax parameter determines how many times PRACH preamble can be sent within one preamble ramping cycle (SIB5&6) maxPreambleCycle defines how many times the PRACH preamble ramping cycle procedure can be repeated before UE MAC reports a failure on RACH transmission to higher layers (SIB5&6) L1 ACK / AICH In average coverage conditions the RRC Connection Setup performance can be improved by tuning the open loop power control parameters These parameters are preambleRetransMax and & maxPreambleCycle powerOffsetPpm powerOffsetP0 Downlink Not detected BS MaxTXPowerUl powerOffsetP0 Initial preamble power …… Uplink Preamble MS Preamble 1 2 …… Preamble preambleRetransMax # PRACH preambles transmitted during one PRACH cycle without receiving AICH response maxPreambleCycle # preamble power ramping cycles that can be done before RACH transmission failure is reported powerOffsetPpm Message part Find some KPIs formula which are defined in RNC HSPA+ and EUL Main difference in performance between R99 Packet and HSDPA • R99 Packet service requires dedicated channels whereas HSDPA users have a shared channel • Speeds of HSDPA are much higher compared to 3G(R99). In real networks, an average HS subscriber gets around 5-8 times throughput, compared to an R99 data user. HSDPA Physical and Transport Channels To support HSDPA new Physical channels have been defined: HS-PDSCH or High Speed Physical Downlink Shared Channel: This is a downlink channel which is both time and code multiplexed. The channelization codes have a fixed spreading factor, SF = 16. Multi-code transmissions are allowed that translates to UE being assigned multiple channelization codes in the same TTI, depending on the UE capability. The same scrambling code sequence is applied to all the channelization codes that form the single HS-DSCH CCTrCH. If there are multiple UE's then they may be assigned channelization codes in the same TTI (multiplexing of multiple UE's in the code domain). HS-DPCCH or High Speed Dedicated Physical Control Channel: This is an uplink channel that carries the Acknowledgements of the packet received on HS-PDSCH and also the CQI (Channel Quality Indication). THE CQI estimates have to be transmitted by the UE every 2.0 ms frame. This information is very important as it ensures reliability and impacts power capacity. HS-SCCH or High Speed Shared Control CHannel: The HS-SCCH is a fixed rate (60 kbps, SF=128) downlink physical channel used to carry downlink signaling related to HS-DSCH transmission. This provides timing and coding information thus allowing the UE to listen to the HS-DSCH at the correct time and using the correct codes to allow successful decoding of UE data. The main features of the physical channel are as follows: Fixed Spreading Factor of 16 for HS-DSCH QPSK and 16 QAM Modulation Static TTI Length of 3 Time Slots = 2ms Fixed CRC of 24 bits Error Correction using 1/3 Turbo Coding To support HSDPA the following new Transport channels have been defined:HS-DSCH or High Speed Downlink Shared channel: The High Speed Downlink Shared Channel is a downlink transport channel shared by several UEs. The HS-DSCH is associated with one downlink DPCH, and one or several Shared Control Channels (HS-SCCH). The HS-DSCH is transmitted over the entire cell or over only part of the cell using e.g. beam-forming antennas. HS Characteristics • Spreading Factor in HSDPA is fixed to 16 and it is not adaptive • Multi-code can be allocated to one user, for example 4 channelization codes of SF=16 can be allocated to a user. • Maximum 15 codes can be used in HSDPA • The number of codes used per user depend on reported CQI • Codes allocated to user only when possible to be used • RBS dynamically allocates the codes to the users every 2 ms HSDPA Multi Code Transmission SF=1 SF=2 SF=4 SF=8 SF=16 Remaining codes used for signalling 15 x SF16 => 15(3.84X106/16) = 3.6X106 symbols/sec QPSK (2bits/symbol) => 3.6X106 x 2 = 7.2 Mbps Physical rates 16QAM (4bits/symbol) => 3.6X106 x 4 = 14.4 Mbps 64QAM (6bits/symbol) => 3.6X106 x 6 = 21.6 Mbps 64QAM (6bits/symbol) => 3.6X106 x 6 x 2 = 43.2 Mbps (MIMO) HSDPA Scheduling 2 msec TTI Scheduling Algorithm HSDPA codes User #1 User #2 User #3 • EQUAL_RATE [5] • MAXIMUM_CQI [4] • PROPORTIONAL_FAIR_HIGH [3] • PROPORTIONAL_FAIR_LOW [2] • PROPORTIONAL_FAIR_MEDUM [1] • ROUND_ROBIN [0] User #4 HSDPA shared channel: - shared in time (2 msec TTI) - codes shared between users (4 users per TTI) • Multi-code transmission, UE is assigned to multiple codes in the same TTI • Multiple UEs may be assigned channelization codes in the same TTI numHsScchCodes The parameter numHsScchCodes controls the number of HSSCCH broadcast per cell. The number of HS users that can be simultaneously allocated resources by the scheduler per 2 ms Transport Time Interval (TTI) is directly related to the number of HS-SCCH broadcast (maximum is 4). If a cell has a high HS traffic load, and a low DCH load, it may be beneficial to increase the number of broadcast HS-SCCH. However, if the overall cell throughput is limited due to power, HS-PDSCH codes or transport limitations, consuming another 128 bit code to support an additional HS-SCCH is unneeded. # Users Per Cell HSDPA throughput meets theory R99 Channels Vs. HSDPA HSDPA Channels • HS-PDSCH – Carries the data traffic – Fixed SF = 16; up to 15 parallel channels – QPSK: 480 kbps/code, 16QAM: 960 kbps/code • HS-SCCH – Signals the configuration to be used next: HS-PDSCH codes, modulation format, TB information – Fixed SF = 128 – Sent two slots (~1.3msec) in advance of HS-PDSCH • HS-DPCCH – Feedbacks ACK/NACK and channel quality information (CQI) – Fixed SF = 256, code multiplexed to UL DPCCH – Feedback sent ~5msec after received data 3G Resources • • The term channel element (CE) is used to quantify processing power in the Node B chipset. The number of channel elements available for users is dependent on hardware configuration, and number of licensed channel elements enabled. In general, channel elements for the common and overhead channels are included with the Node B, and do not take from the pool of licensed channel elements. In the Ericsson Node B, channel elements for uplink are located on the Random Access and Receiver (RAX) board. The total number of CE available is dependent on the type of RAX board, as well as the number of RAX boards that are installed in the Node B. As an example, the high capacity 3206 RBS can contain 8 RAX R2 boards with 128 channel element each, for a total of 1024 channel elements. The channel elements for the downlink are located on the transmitter card. The total number of CE available is dependent on the number of transmitter boards installed. The 3206 RBS can be configured with 2 transmitter cards with 256 channel elements each, for a total of 512 channel elements. The number of channel elements utilized by a UE is dependent on several factors. This includes the RAB type used, as well as the soft/softer handover state of the UE. Table 5 provides some examples of downlink and uplink CE usage based on RAB type. As the table shows, RABs with high data rates require additional processing and therefore more channel elements. When a UE is in soft handover, the CE requirement obviously increases since multiple Node Bs are involved. However, when a UE is in softer handover, the same CE will process the multiple radio links within the same Node B. Channel element allocation for EUL Traffic on the HS-DSCH will not consume channel elements. However, every HSDPA connection will require A-DCHs for UL/DL signaling and UL traffic. A-DCHs are dedicated channels, which consume channel elements. Dimensioning of DL resources for A-DCH is not needed since DL A-DCHs do not consume resources from the normal pool of SW licensed channel elements. However, resources for UL A-DCH have to be considered since they consume channels elements from the normal SW licensed pool. Figure shows that if the R99 traffic load is low in the RBS the EUL scheduler will have more channel elements to share between the EUL users. The EUL users will thus have a higher probability of being scheduled to high rates at low R99 traffic. If R99 traffic load increases, channel elements will be removed from the EUL domain and EUL users will be scheduled to lower rates. The maximum number of channel elements that can be allocated by E-DCHs can not be higher than the EUL license, even if there are channel elements available in the SW licensed pool. OVSF and CE Consumption for DL DCH service OVSF and CE Consumption for UL DCH service OVSF and CE Consumption for HSUPA OVSF Code Usage CE (Channel Element) Congestion in CE (Channel Element) in Uplink is called Uplink CE Congestion. In 3G network mostly CE congestion observed in Uplink Direction. Lack of channel elements could be due to insufficient UL (RAX board) or DL (TX board) hardware capacity. Channel element capacity could be also software limited. Admission control is restricted by ulHwAdm and dlHwAdm parameters. They should be set at 100% so no hardware is limited for RRC/RAB setup. The INVL command help us to see the CE Congestion at RAX or TX could be indicated by RBS counters pmUlCredits and pmDlCredits respectively. CE Congestion Causes and Solutions Causes: • • • • Shortage of License. Neighbor site down Overshooting High number of AC block events on LackDlHw would indicate issues with TX board and LackUlHw would indicate issues with RAX board. Congestion at RAX or TX could be indicated by RBS counters pmUlCredits and pmDlCredits respectively. Congestion per spreading factor (SF) can be also measured using pmSetupFailureSfXX RBS counters from the BasebandPool (BBP) on the uplink (UL BBP) and the downlink (DL BBP). Solutions for CE Congestion: • • • • • • • • Upgrade the CE license according to your vendor. R99 services uses more CE so try to reduce R99 services. There are several parameters which can help R99 Service utilization optimization. Load Balancing between 2G and 3G or 3G and 4G can also help to reduce Uplink CE Congestion. Decrease the Max Bit Rate Reduce Initial bit Rate from 64 to 32kbs Enable the DCCC Algorithm Check that ulHwAdm and dlHwAdm parameters are set to 100% Check numHsResources, numEulResources at the node B (long term solution) Reduce value of sf8Adm to 0 (short term solution) Check for hardware failures on RAX and TXB boards and given the case, order its replacement. Order an additional new RAX or TXB board, depending on the specific case. Reduce the eulServingCellUsersAdmTti2 value. Low soft handover success rate due to UL HW congestion The SHO handover success rate in a RNC degraded mainly due to a site encounter the UL HW congestion. But it has been taken care of after UL CE license upgrade. ASE (Air-interface Speech Equivalent) ASE of a radio link = relative value, defined as the air interface load relative to a speech radio link (12.2kbps, 50% activity). A radio link with an ASE of 3 in DL, is expected to generate as much interference in downlink as 3 speech radio links in the cell. General method of estimating ASE value for a specific service Code Tree Consumption Lack of Canalization Code (pmNoFailedRabEstAttemptLackDlChnlCode) Note: The code tree consumption is measured in percentage of the total tree size by excluding the fixed codes allocated for HSDPA (i.e. the higher the number of codes allocated for HSDPA the smaller will be the available tree and higher the relative consumption). The admission limit is set by dlCodeAdm (as a percentage). Logs Handling RNCSM02> h lg ******************************************************* lg[aevsyuoldhmircfx] [-l <logdirectory|logfile>] [-m <minustime>] [-p <plustime>] [-s <startdate>] [-e <enddate>] [|<unixcmds>] ******************************************************* Fetching and/or processing of node logs (alarm, event, availability, system, etc) Options: ******** - a: parse alarm log (CELLO_ALARM_LOG.xml) - e: parse event log (CELLO_EVENT_LOG.xml) - v: parse availability log (CELLO_AVAILABILITY_LOG.xml) - s: parse system log (/c/logfiles/systemlog/xxxsyslog) - u: parse upgrade log (Trace.log and Trace.log_old) - o: parse command log (CORBA_AUDITTRAIL_LOG.xml) - y: parse securityevent log (CELLO_SECURITYEVENT_LOG.xml). - l: parse coli log (SHELL_AUDITTRAIL_LOG.xml). - h: parse hili log (CELLO_HWINVENTORY_LOG.xml). This file must first be generated with the command "hili mk". - d: show node restarts and system downtime, based upon info of the system log and availability log. - x: show alarms active on a specific date/time, based upon info of the alarm log. - m: merge the different logs together (eg: lgaevm will merge alarm/event/availability logs). Not supported with "h" option. - i: inverse chronological order. - r: refetch the logs from the node. - c: print the output in csv format (semicolon separation). - f: fetch the logs only and store them in a directory on the workstation. Handover Types of WCDMA Handover and Overall Process Initiation There can be various types of WCDMA handover as follows: • • • • • Soft & Softer handover 3G-2G IRAT handover 2G-3G IRAT handover Inter Frequency handover Load sharing UE Measurements / Evaluation Measurements Filtering, Offsetting, Weighting Evaluation Reporting RNC Evaluation Execution WCDMA RAN HO Entities • • • • • Soft/Softer Handover Execution (SHO_Eval) Inter-Frequency Handover Execution (IFHO_Eval) Inter-RAT Handover Execution (IRATHO_Eval) Inter-RAT Cell Change Execution (IRATCC_Eval) CN-HHO Execution (CN-HHO_Eval = Hard Handover via Core Network evaluation algorithm) • HS-DSCH Cell Change Execution (HSCC_Eval = Serving HS-DSCH [High Speed Downlink Shared Channel] Cell Change evaluation algorithm) Entities Involved in Reporting, Evaluation, and Execution of Handover-Related Functions Soft/Softer Handover, Inter-Frequency Handover, Inter-RAT Handover (including the particular case of Service Based Handover), Inter-RAT Cell Change, Hard Handover via Core Network, and serving HSDSCH Cell Change all consist of an evaluation part and an execution part. The evaluation part initiates and evaluates UE measurements on neighbor cells. The execution part, triggered by the evaluation results, allocates resources (if necessary) and performs the actual Handover (including serving HS-DSCH Cell Change) or Inter-RAT Cell Change. UEs are configured to evaluate and send measurement reports to the system only when certain events occur. UE Associated Cell sets for Measurement • Active Set The cells involved in soft handover and measured by the UE • Virtual Active Set The Active Set associated with a non-used frequency for support of Inter-Frequency evaluation • Monitored Set The cells only measured by the UE and not part of the Active Set. The monitored set can consist of intra-frequency, Inter-Frequency and Inter-RAT cells or list of (neighboring) cells whose pilot channel Ec/Io is continuously measured but not strong enough to be added to the active set. • Detected Set The intra frequency cells (P-CPICH scrambling codes) detected by the UE and they are not in relation definition. Monitored Set Creation • After the UE has entered state CELL_DCH or after the Active Set is updated (including successful IFHO), the Monitored Set is created. It is based on the neighbor cells of the cells in the Active Set and is typically updated when the Active Set is updated. • The Monitored Set consists of three subsets namely – IAF Monitored Subset – IEF Monitored Subset – GSM Monitored Subset Measurement Handling (Meas_Handl) • The Measurement Handling algorithm prepares a list of cells that the UE will measure on. The algorithm prepares a message to send to the UE containing the measurement criteria, as well as the list of cells to measure on, in accordance with the handover parameters defined by the operator and the cells currently used in the active set – The number of Intra-frequency cells in the Monitored Set + the Active Set cells is limited by 3GPP to 32. – The number of Inter-Frequency cells in the Monitored set is limited to 32. – The number of Inter-RAT cells in the Monitored set is limited to 32. Overview of Sets and Subsets of Cells Soft HO Vs. Softer HO For soft handover DL: For soft handover the situation is very similar in the downlink direction. In the mobile station the signals received from the two different base stations are combined using UL: The received signals can no longer be combined in the base station but are routed to the RNC. The combining follows a different principle; in the RNC the two signals are compared on a frame-by-frame basis and the best candidate is selected after each interleaving period. For softer handover Both in the DL and UL received signal can be combined in the same Rake receiver, hence MRC (maximum Ratio Combining) can be used in both direction Soft & Softer handover In Soft Handover the UE is connected to more than one RBS simultaneously. Soft Handover is possible and necessary with a frequency re-use of one. At least one radio link is always active and there is no interruption in the dataflow during the actual handover. The signals are received in the UE and combined in the RAKE receiver to give protection against fading. In Softer Handover the UE communicates with one RBS through several radio links. The Softer Handover is a handover between two or more cells of the same RBS. In addition to this code limiting effect described above, soft and softer handover also add to the consumption of OVSF codes. Assuming that the average soft handover factor was 1.8 radio links per user, each user would require 1.8 codes on an average (excluding the HSPDSCH). In Soft Handover the combining techniques of information from different radio paths are different for uplink and downlink. In the uplink selective combining is used; the RNC receives transport blocks from different RBSs and chooses the best block according to the CRC. In the downlink the signals are combined in the Rake receiver in the UE, using MRC (Maximum Ratio Combing). In Softer Handover different diversity branches, both in the uplink and downlink, can be combined in the same Rake receiver, hence MRC can be used in both directions. Handover Events To enable handovers, the UE is measuring on CPICHs in the active and monitored set, using the searcher finger of the Rake receiver, When a new pilot enters the reporting range an event is triggered. Then the UE sends a report to the RNC for evaluation. When new resources are needed the Soft/Softer Handover Execution checks with Admission Control if they are available, before execution. The UE gets a message to add/replace or remove the new cell and information about the updated monitored set. RNC RNC UE UE MEASUREMENT CONTROL message (BCCH, DCCH) MEASUREMENT REPORT message RNC RNC Evaluation Evaluation Perform Perform Measurement Measurement UE UE Evaluation Evaluation (DCCH) Execution Radio Radio Link Link Addition Addition ACTIVE SET UPDATE (DCCH) ACTIVE SET Radio Radio Link Link Removal Removal Radio Radio Link Link Add/Remove/Replace Add/Remove/Replace UPDATE COMPLETE RNC RNC Evaluation Evaluation MEASUREMENT CONTROL message (DCCH) UeMeasControl measQuantity1 enumRef:SupportedMeasQuantities ---------------------------------------------------------------------------------------------Used by UE functions for intra-frequency measurements (in CELL_DCH). Quantity to measure for the chosen mode. The value of this attribute will set the message data CPICH_Ec/No or CPICH_RSCP accordingly. Dependencies: If CN Hard Handover is supported and measQuantity1 is changed, (the measurement method is changed), the attribute intraFreqCnhhoPenalty in MO Handover must be correctly set for the new measurement method. The system will not enforce this. Change takes effect: Ongoing connections (next switch to CELL_DCH) Default=CPICH_EC_NO Range: 1,2 Event-1a-Addition of a RL When a primary CPICH, not included in the Active Set, enters the reporting range, event 1a occurs. The UE sends an event 1a report to the RNC. If the reported cell is a valid neighbor and the Active Set is not full, the cell is proposed as an addition to the Active Set. The event 1a reporting is configurable through the parameter reportingRange1a. > (reportingRange1a + hysteresis1a/2) for timetotrigger1a duration Hysteresis1a = 0 = No Hysteresis Reportingrange1a= 6 = 3 dB Timetotrigger1a = 9 = 200ms Event-1b-Removal of a RL When a primary CPICH, included in the Active Set, leaves the reporting range, event 1b occurs. The UE sends an event 1b report (proposal of Radio Link removal) to the RNC. If the report includes more than one cell, all cells are proposed by the evaluation to be removed. However, one cell is always kept in the Active Set. The event 1b reporting is configurable through the parameter reportingRange1b. < (reportingRange1b - hysteresis1b /2) for timetotrigger1b duration Hysteresis1b = 0 = No Hysteresis Reportingrange1b= 12 = 6 dB Timetotrigger1b = 13 = 1280ms Event-1c-Replacement of a RL When a primary CPICH, not included in the Active Set, becomes stronger than the weakest CPICH in the Active Set, event 1c occurs. The UE sends an event 1c report to the RNC. If the reported cell is a valid neighbor and the Active Set is full, the reported cell is proposed as a replacement for the weakest cell in the Active Set. The event 1c reporting is configurable through the parameter hysteresis1c Hysteresis1c = 2 = 1 dB Timetotrigger1c = 11 = 320ms Event-1d-Change of best cell in AS When any of the primary CPICHs become stronger than the best primary CPICH, event 1d occurs. The UE sends an event 1d report to the RNC. the reported cell is a valid neighbor and the Active Set is not full, the cell is proposed as an addition to the Active Set. If the Active Set is full, the cell is proposed as a replacement for the weakest cell in the Active Set. The event 1d reporting is configurable through the parameter hysteresis1d. Hysteresis1d = 15 = 7.5 dB Timetotrigger1d = 12 = 640ms Counters & KPIs related to SHO pmRlAddAttemptsBestCellSpeech : CS Speech RABs pmRlAddAttemptsBestCellCsConvers : CS Conversational 64kbps RABs pmRlAddAttemptsBestCellPacketHigh : high-rate (greater than 64 kbps) PS Interactive RABs pmRlAddAttemptsBestCellPacketLow : low –rate (less than 64 kbps) PS Interactive RABs pmRlAddAttemptsBestCellStandAlone : Stand-alone SRB 13.6 connections pmNoTimesCellFailAddToActSet : Number of times that a cell could not be added to the active set of a UE. pmSumUesWith1Rls1RlInActSet : Sum of all sample values recorded during a ROP for the number of UEs with one radio link set and one radio link in the active set. pmSumUesWith1Rls2RlInActSet pmSumUesWith1Rls3RlInActSet SHOSuccess = 100 * pmNoTimesRlAddToActSet / (pmNoTimesRlAddToActSet + pmNoTimesCellFailAddToActSet) Accepted range is 99 SHO Overhead = (1* pmSumUesWith1Rls1RlInActSet +2* pmSumUesWith1Rls2RlInActSet +3* pmSumUesWith1Rls3RlInActSet )/(pmSumUesWith1Rls1RlInActSet + pmSumUesWith2Rls1RlInActSet + pmSumUesWith3Rls1RlInActSet) Accepted range is 1.5 Inter Frequency & Inter RAT Handover Inter-Frequency handover is only attempted if IfHoAllowed is set to Allowed and FddIfHoSupp is set to On for the current UeRc state. Inter-RAT handover is only attempted if GsmHoAllowed is set to Allowed and FddGsmHoSupp is set to On for the current UeRc state. If both Inter-Frequency handover and Inter-RAT handover are allowed and both Inter-Frequency and Inter-RAT neighbors cells exist for the cells in the Active Set, the decision to perform Inter-Frequency or Inter-RAT handover is based on a configurable parameter, hoType, defined per cell The Inter-frequency or IRAT handover is triggered based on three criteria, Ec/No, RSCP) and UE Tx Power. These events are also used for IRATHO and IRATCC. Based on that Event 2d,2b,2f,3a will occur. What is compressed mode? During inter-frequency handover the UE’s must be given time to make the necessary measurements on the different WCDMA carrier frequency. 1 to 7 slots per frame can be allocated for the UE to perform this intra frequency (hard handover). These slots can either be in the middle of the single frame or spread over two frames. This compressed mode operation can be achieved in three different methods: • • • Decreasing the spreading factor by 2:1. This will increase the data rate so bits will get sent twice as fast. Puncturing bits. This will remove various bits from the original data and hence reduce the amount of information that needs to be transmitted. The higher layer scheduling could also be changed to use less timeslots for user traffic Inter Frequency Handover-Event 2d,2b,2f Ran quality of current frequency < (usedFreqThresh2dEcno + serviceOffset2dEcno-hysteresis2d/2) for a duration timetotrigge2d—Event 2d triggers and UE enters the compressed mode. Ran quality of current frequency > (usedFreqThresh2dEcno + serviceOffset2dEcnohysteresis2d/2+usedFreqRelThresh2fEcno) for a duration timetotrigge2f—Event 2f triggers and UE exists the compressed mode. Inter Frequency Handover-Event 6d, 6 The UE is also configured for event trigger decision based on threshold ueTxPowerThresh6b Reporting event 6d and 6b If the UE TX Power reaches maximum, and the condition is maintained during a time not less than timeTrigg6d, then event 6d occurs and Inter-Frequency or GSM/GPRS measurements need to be performed by UE. If the UE TX Power goes below ueTxPowerThresh6b threshold, and the condition is maintained during a time not less than timeTrigg6b, then event 6b occurs and the UE is requested to stop measurements on Inter-Frequency GSM/GPRS cells. Inter Frequency Handover-Sequence If the measured quality of the best cell in the Active Set on the currently used frequency is below usedFreqTresh2dEcno + usedFreqThresh4_2bEcno, and the quality and RSCP of the measured best cell on unused frequency both are above nonusedFreqThresh4_2bEcno and nonusedFreqThresh4_2bRscp (also taking the hyst4_2b into account), the UE sends a measurement report after timeTrigg4_2b to the SRNC to perform the handover. Inter Frequency parameters usedFreqThresh2dRscp = -102 (Cell Level) usedFreqThresh2dEcno = -13 (Cell Level) Hysteresis2d=0 Hysteresis2f =0 nonUsedFreqThresh4_2bRscp= -95 nonUsedFreqThresh4_2bEcno= -10 timeToTrigger2dEcno=320 timeToTrigger2dRscp=320 timeToTrigger2fEcno=1280 timeToTrigger2fEcno=1280 timeToTrigger6d=320 timeTrigg4_2b=100 timeTrigg6b=1280 ueTxPowerThresh6b=20 usedFreqRelThresh2fEcno=2 usedFreqRelThresh2fRscp=3 usedFreqRelThresh4_2bEcno=-1 usedFreqRelThresh4_2bRscp=-3 IRAT parameters usedFreqThresh2dRscp = -102 (Cell Level) usedFreqThresh2dEcno = -13 (Cell Level) Hysteresis2d=0 Hysteresis2f =0 timeToTrigger2dEcno=320 timeToTrigger2dRscp=320 timeToTrigger2fEcno=1280 timeToTrigger2fEcno=1280 timeToTrigger6d=320 usedFreqRelThresh2fEcno=2 usedFreqRelThresh2fRscp=3 Hysteresis3a=0 timeToTrigger3a=6 utranRelThresh3aEcno=0 utranRelThresh3aRscp=-5 measQuantity1= 2 (CPICH_EC_NO) Inter RAT Handover-Event 2d,3a,2f Ran quality of current frequency < (usedFreqThresh2dEcno + serviceOffset2dEcno-hysteresis2d/2) for a duration timetotrigge2d—Event 2d triggers and UE enters the compressed mode. Ran quality of current frequency > (usedFreqThresh2dEcno + serviceOffset2dEcno+hysteresis2d/2+usedFreqRelThresh2fEcno) for a duration timetotrigge2f—Event 2f triggers and UE exists the compressed mode. Inter RAT Handover-Event 2d,3a,2f estimated quality of the currently used radio link < usedFreqTresh2dEcno - utranRelThresh3aEcno – Hysteresis3a/2 estimated quality of the target GSM cell > gsmThresh3a+Hysteresis3a/2 for a time duration timetotrigger3a Inter RAT Cell ChangeEvent 2d,3a,2f Inter RAT HandoverEvent 2d,3a,2f Inter Handover 2G-3G Triggering will be based on QSC settings when to start WCDMA measurements. The 2G-3G neighbor list has to be defined for every cell in BSC which will be broadcasted on the SACCH. This list can be the same as the list broadcast on BCCH to Multi-RAT MSs in idle mode, but it is also possible to set it separately in order to have different UMTS neighbors in idle and active mode. The Multi-RAT mobile is informed of how many UMTS cells (0-3) shall be reported in the measurement report. This is set by parameter FDDMRR. The remaining positions will be used for GSM cells. 2 criteria's must be full filled for a GSM to UMTS handover to happen. • Percentage of idle TCH in the serving cell ≤ ISHOLEV • CPICH Ec/No > MRSL WCDMA Load Sharing Techniques Load sharing enhances the performance of a Radio Access Network by pooling together resources from different parts of the entire network. The following load-sharing features are available in the WCDMA RAN: Inter-Frequency Load Sharing HS IFLS non HS IFLS Directed Retry to GSM Load based HO to GSM Inter-frequency load based HO Service based HO Inter-Frequency Load Sharing-Configuration This feature is activated in an RNC by setting the parameter loadSharingRrcEnabled to TRUE. The attribute loadSharingCandidate specifies whether the target cell is a load-sharing neighbor of the source cell. Possible values for loadSharingCandidate are TRUE and FALSE. There should be no more than one neighbor per carrier for each source cell, and all load-sharing neighbors should be co-located. This feature uses the same neighbor-cell relations as Inter-Frequency Handover. If a relation is created for Load Sharing purpose but not wanted by Inter-Frequency Handover, the handover can be suppressed by setting the cell parameter hoType to NONE or GSM_PREFERRED. Inter-Frequency Load Sharing-Operation The amount of resource excluded from load-sharing use is specified by the cell parameter loadSharingMargin as a percentage of pwrAdm. The performance of Inter-Frequency Load Sharing can be monitored via the following three counters: • pmTotNoRrcConnectReq gives the total number of RRC connection requests in a cell. • pmNoLoadSharingRrcConn gives the number of RRC redirections performed for load-sharing reason in a cell. • pmNoOfReturningRrcConn gives the number of calls that has returned to the original frequency after an RRC-redirection. HS/Non HS IFLS • IFLS feature will help to sending exceedig traffic in a cell to other carriers in order to balance the number of users and avoid congestion. This feature works for HS and Non HS IFLS when activated at RNC level: – – • rncfeature hspaloadsharing TRUE (HS IFLS at RNC level) rncfeature dchloadsharing TRUE (Non HS IFLS at RNC level) In order to use this feature is necessary to create for each cell a coverage relation with all other carriers of the same sector. Next step is configure and activate the feature at coverage relation level: – – set UtranCell=WXXX,CoverageRelation=WXXX relationCapability dchLoadSharing=1 set UtranCell=WXXX,CoverageRelation=WXXX relationCapability hsLoadSharing =1 › The following initial configuration was used: – – – – – – hsPathlossThreshold 120 (coverage relation level) (Pathloss threshold used for both HS IFLS) pathlossThreshold 170 (sector level) (A pathloss check is performed before triggering a blind IFHO to a candidate cell, when performing load sharing from DCH state. If the pathloss is high er than this threshold, the blind IFHO is not allowed.) hsIflsMarginUsers 10 (sector level) (Margin for HS interfrequency load sharing, relative to the admission limit hsdpaUsersAdm) hsIflsThreshUsers 20 (sector level) (load sharing triggered for source cell) dchIflsThreshPower -> 0 (power threshold for DCH load sharing) IFLS (inter Frequencies Load Sharing) UtranCell hsIflsThreshUsers long -----------------------------------------------------------------------------------------------------------------------------------Threshold for triggering HS interfrequency load sharing in the source cell, relative to the admission limit hsdpaUsersAdm. If more than hsIflsThreshUsers/100 * hsdpaUsersAdm HS users are present when a RAB transition is being evaluated, load sharing is triggered. Setting this parameter to 0 disables HS interfrequency load sharing in this cell. Only used if RncFeature=HspaLoadSharing or RncFeature=IflsRedirectDownswitch (or both) is activated. Feature: HspaLoadSharing, IflsRedirectDownswitch Change takes effect: Immediately Unit: % Range: 0 to 100, Default=0 UtranCell hsIflsMarginUsers long -----------------------------------------------------------------------------------------------------------------------------------Margin for HS interfrequency load sharing, relative to the admission limit hsdpaUsersAdm. When calculating remaining free resources in the cell during evaluation of a RAB transition, this margin is subtracted from the result, making the cell look more loaded than it is and therefore making it a less likely target for HS inter-frequency load sharing decisions. Only used if RncFeature=HspaLoadSharing or RncFeature=IflsRedirectDownswitch (or both) is activated. Feature: HspaLoadSharing, IflsRedirectDownswitch Change takes effect: Immediately CPICH Ecno Thr & iflsMode • The parameter iflsCpichEcnoThresh defines the measured downlink EcNo value above which HS and Non HS IFLS reconfiguration from FACH or URA are allowed. When configured as -24 means that this value is not used and reconfigurations are always allowed when HS and/or Non HS IFLS are activated. • iflsMode defines the RAB reconfigurations that can trigger and IFLS event. This can be due to: – – – • RAB Establishment (0) Upswitch attemps (1) Both (2) In our network we are usingfollowing configuration: – – iflsCpichEcnoThresh -24 iflsMode 2 (RAB Establishment and Upswitch attempts) HS Pathloss Threshold • IFLS feature works by means of Blind Handover that is, is not performing measurements before sending the traffic to other carriers as a common Handover would made. For this reason is commonly seen RAB issues affecting the PS accessibility performance due to big difference in coverages. • A tuning of the parameter hsPathlossThreshold will help to improve the chances of success by doing a check between the source and target before launch a blind handover. If the pathloss is higher that threshold the IFLS is not allowed. For tis case we use the configuration: – – hsPathlossThreshold 115 (for 850 carrier) hsPathlossThreshold 120 (for 2100 carrier) IFLS at downswitch • This feature offers the possibility to redirect the User Equipments to another carrier, this triggered by in-activity downswitches from DCH to FACH or URA states or fastDormancy. • This feature only should be activated if the feature IflsRedirectDownswitch is active on the RNC. • For this case, the configuration selected was only from DCH to FACH. • • • • • • • • • get utrancell=”XXX” hsiflsdownswitchtrigg ====================================================================== MO Attribute Value ====================================================================== UtranCell=”XXX” hsIflsDownswitchTrigg Struct{3} >>> 1.toFach = 1 (ON) >>> 2.toUra = 0 (OFF) >>> 3.fastDormancy = 0 (OFF) Directed Retry To GSM If a call is chosen for Directed Retry to GSM, the request for the speech RAB will be rejected with cause “Directed retry” and then a request is made to the core network to relocate the UE to a specific GSM cell, using the Inter-RAT handover procedure . The target cell must be co-located with the WCDMA cell. Directed Retry to GSM Directed Retry to GSM Traffic Case Directed Retry to GSM-Configuration Directed Retry to GSM is activated in an RNC by setting the flag loadSharingDirRetryEnabled to TRUE. One GSM target can be defined for each WCDMA cell via the cell parameter directedRetryTarget. It must be ensured that the correct GSM targets have been defined and that they are indeed co-located with their respective source cells in the WCDMA RAN. Directed Retry to GSM-Operation There are two parameters for this feature: • loadSharingGsmThreshold specifies the minimum cell load at which offloading to GSM starts. • A value of 0 means the feature is always on, 100 means it is always off, and 50 means off-loading starts as soon as the cell load rises above 50% of the admission limit. loadSharingGsmFraction specifies the percentage of Directed Retry candidates to be diverted to GSM while the cell load is above the specified load threshold. • A value of 0 means no diversion will take place and a value of 100 means all calls qualified for Directed Retry will be diverted. The success rate can be monitored by two counters and they are: • pmNoDirRetryAtt gives the total number of Directed Retry attempts. • pmNoDirRetrySuccess gives the number of successful attempts. Load based HO to GSM This feature enables HO to GSM for speech calls, when the load is high in a WCDMA cells. Following different load quantities are used to trigger this functionality• DL power load.(>PwrAdm) • DL Code tree load (>DlCodeAdm) • UL or DL RBS HW load. (UlHwAdm/DlHwAdm) • UL or DL ASE load. (UlAseAdm/DlAseAdm) If high load is detected for one or several of theses load quantities, speech-only users can be selected for GSM HO attempts. The UEs are instructed to perform measurements for GSM cells , and HO attempts can be triggered if the UEs detect and report a good enough GSM cell. Load based HO to GSM-Configuration This feature will use the Admission control functionality as a way to detect high load in a WCDMA cell. loadbasedHoSupport is set to True and lbhoType is set to lbho_GSM in the cell. lbhoMinSpeechUsers can be set so that a number of speech users are allowed to remain in the cell before the loadbased HO is activated. lbhoMinTriggerTime is a timer which can be set to slow down the loadbased HO functionality, so that the loadbased HO attempts happen more seldom. lbhoMaxTriggeredUsers is used to define the maximum number of HO triggered simultaneously. Load based HO to GSM-Operation To perform GSM HO number of conditions are checked and they are as follows: • CS speech only user, and it is not an Emergency call. • Compressed mode and other HO attempts not already ongoing for the user. • Service handover IE not equal to "Shall not". • fddGsmHoSupport is ON. • The connection is not originating from another RNC over Iur. The total number of compressed mode users in a cell is limited by the parameter compModeAdm, and if many Load based HO attempts are initiated, the number of coverage triggered HO attempts might be limited. • The counter “pmSumCompMode” together with “pmSamplesCompMode” are used to monitor the number of radio links in compressed mode per UtranCell before and after the feature is activated. Load based HO to GSM-Configuration Cedr command : Inter-frequency load based HO This feature enables Inter-frequency HO for speech calls, when the load is high in a WCDMA cell. The intention is to be able to offload the WCDMA network to another external WCDMA network. For utilize this feature the network uses Core Network Hard Handover, but it is also possible to offload to IF cells within the same RNS. The load quantities and general functionality are the same as for Load based HO to GSM. For defining IF HO IF neighbours are used. Inter-frequency load based HO-Configuration This feature will use the Admission control functionality as a way to detect high load in a WCDMA cell. loadbasedHoSupport is set to True and lbhoType is set to lbho_IF in the cell. lbhoMinSpeechUsers can be set so that a number of speech users are allowed to remain in the cell before the loadbased HO is activated. lbhoMinTriggerTime is a timer which can be set to slow down the loadbased HO functionality, so that the loadbased HO attempts happen more seldom. The threshold nonUsedFreqThresh4_2bEcn0 + serviceOffset2dEcno is used for the IF quality as for normal IFHO, the value 0 is used for the WCDMA quality. Inter-frequency load based HO-Operation In order to support different network configurations and scenarios, the creation of the IF monitored set is filtered when triggered by IF LBHO. The value of parameter ifLbhoMode is as follows: • ifLbhoMode = 1 Include all defined IF neighbour cells. • ifLbhoMode = 2 Include only “Non-Iur external” IF cells used for CNHHO. • ifLbhoMode = 3 Do not include “Non-Iur external” IF cells used for CNHHO. The counter “pmSumCompMode” together with “pmSamplesCompMode” can be used to monitor the number of radio links in compressed mode per UtranCell before and after the feature is activated. SBHO Feature description • The feature Service Based Handover makes it possible to restrict or promote Inter RAT Handover (Inter System Handover) based on IMSI and Call Type. The process is trigged by the assignment procedures. • By using this feature subscribers can be directed (via Inter RAT Handover) to a preferred access network (GSM or WCDMA) based on the type of service requested. • The Service Based initiated IRAT handover is executed as a “normal” IRAT handover after that measurement has been made on the neighbouring GSM / WCDMA cells (the measurements takes normally about 5-10 seconds). So, Service Based Handover is not a “blind” handover. SBHO –Service Indicators(SI) • Should: The system should immediately initiate required actions, e.g. compressed mode measurements to determine the correct target cell, in order to perform an inter-RAT transfer of the connection to GSM as soon as possible. • Should Not: Neither Compressed Mode for GSM measurement, nor connection transfer to GSM shall be initiated, unless the quality/strength requires an inter-RAT transfer in order to save the connection. • Shall Not: Neither Compressed Mode for GSM measurements, nor connection transfer to GSM shall be initiated, regardless of any radio related reason to perform such actions. • Missing value: The system shall initiate required actions, e.g. compressed mode measurements to determine the correct target cell, when this is required for radio network reasons, e.g. bad signal quality. SBHO –Service Indicators(SI) HSDPA cell change 3 licensed features to be activated for HSDPA/Eul cell change. HSPA Cell change between HSPA capable cells: A moving UE with an HSPA ongoing call will attempt to perform a cell change each time an event 1d HS, 1b or 1c is triggered. The call is maintained on HSPA if the target cell is HSPA capable and is not rejected by admission control. hsTimeToTrigger1d : 640 hsQualityEstimate : 1 (CPICH_RSCP) HSPA cell change to non-HSPA capable cell : If the HSPA UE is trying to perform cell change to a non-HSPA cell the call can be steered to DCH. The parameter hsToDchTrigger can be used to enable the transition from HS-DSCH to DCH hsOnlyBestCell : FALSE Eul cell change When one UE with an active EUL connection moves towards a cell that is not EUL capable, the new cell is not added to the active set. Instead, the RNC keeps count of add and replace events reported from the UE and in which the RSCP or Ec/N0 level is greater than that in the serving cell by event1dRncOffset dB When the number of events exceeds a threshold event1dRncThreshold dB, the connection is reconfigured to DCH/HSDPA. Exactly the same happens if EUL 2 ms TTI is used and the candidate cell is only supporting 10 ms TTI. In this case the UE will be down switched to R99, from where it may perform channel switching to EUL 10 ms TTI. Initiation • Event Based triggering where UE is involved in the decision. • Evaluation and reporting can be based on CPICH Ec/No or CPICH RSCP. – SHO , CNHHO : CPICH Ec/No is default – HSCC Evaluation : CPICH RSCP is default • For IRAT HO and IFHO, UE Tx (UL) power can also be taken as an input Measurements •From the Ue perspective all the cells are divided into one of these subsets according to 3GPP – Active Set (AS): The cells involved in soft handover and measured by the UE – Monitored Set (MN): • The monitored set is created from the neighbor cell lists of all the cells in the Active Set • The max number of cells in each set is 32. – Unmonitored set: cells excluded from MN set because MN set is full. UE is not ordered to measure them. – Detected Set (DN) : The intra frequency cells detected by the UE but not part of Active Set or monitored set. (Can then be an Unmonitored or a Missing neighbor) UMTS Handover Events • • • • • • • • • • • • • • • Event 1A: A Primary CPICH enters the reporting range; addition of a radio link. Event 1B: A primary CPICH leaves the reporting range; removal of a radio link. Event 1C: A non-active primary CPICH becomes better than an active primary CPICH; replacement of the worst cell in AS. Event 1D: Change of best cell. Event 1E: A Primary CPICH becomes better than an absolute threshold Event 1F: A Primary CPICH becomes worse than an absolute threshold Event 1G: Change of best cell (TDD) Event 1H: Timeslot ISCP below a certain threshold (TDD) Event 1I: Timeslot ISCP above a certain threshold (TDD) Event 2A: Change of Best Frequency. Event 2B: The estimated quality of the currently used frequency is below a certain threshold and the estimated quality of a non-used frequency is above a certain threshold; handover to inter-frequency neighbors Event 2C: The estimated quality of a non-used frequency is above a certain threshold. Event 2D: The estimated quality of the currently used frequency is below a certain threshold ; start compressed mode to measure interfrequency WCDMA or GSM neighbors. Event 2E: The estimated quality of a non-used frequency is below a certain threshold. Event 2F: The estimated quality of the currently used frequency is above a certain threshold; stop compressed mode & stop measure inter-frequency WCDMA or GSM neighbors Event-triggered reporting The User Equipment (UE) continuously monitors the radio environment. Not only defined neighbor cells are measured, but also cells that are undefined neighbors can be detected with the background scanning process. The UE is configured to evaluate and send measurement reports to the system only when certain events occur, such as when the measurement result for a cell fulfills certain criteria. SHO Process End result of the process is one of the following Radio Link addition Radio Link removal Combined Radio Link addition and Radio Link removal New proposal rejection, actual Active Set is maintained Connection is released Measurement Control (which contains the list of cells the UE has to measure) might not be sent in case there is no change in the Monitored set from previous state. Good Counters for HO This issue occurs when the target cell in Hanover has problem for instance • Transmission • Capacity • Channel Element limitation At the first step, the relation must be check (pmRlAddAttemptsBestCellSpeech and pmNoTimesCellFailAddToActSet) And find the problematic neighbor. If there is not any problematic neighbor the decrease of EUL admission threshold can help us pmRlAddAttemptsBestCellSpeech Number of attempted radio link additions for calls that included any CS Conversational Speech RAB (including AMR Single-mode 12.2, AMR-NB Multimode single- and multi-rate, and AMR-WB). Condition: Incremented by one in the best cell in the active set when an attempt is made to add a new RL to the active set or to replace an RL in the active set, for a call that includes a CS Conversational Speech RAB. The counter is incremented after a handover proposal from the handover evaluation function or after the RNC receives an RNSAP Radio Link Addition Request message. pmNoTimesCellFailAddToActSet Number of times that a cell could not be added to the active set of a UE. Condition: Incremented by one in the target cell (the cell that could not be added to the active set), when any of the following occurs during an attempt to add an radio link: - admission is not granted - it is not possible to allocate a downlink channelization code - the RNC receives an NBAP Radio Link Setup Failure message from the RBS, indicating that the Radio Link Setup procedure failed - the RNC receives an NBAP Radio Link Addition Failure message from the RBS, indicating that the Radio Link Addition procedure failed - the Radio Link Setup or Radio Link Addition procedure times out in the RBS - the RNC receives an RRC Active Set Update Failure message from the UE, indicating that the Active Set Update procedure failed - the Active Set Update procedure times out in the UE pmEnableHsHhoAttempt Number of attempted hard handovers to an HS-DSCH cell, for which this cell was the best cell in the source active set (the active set when the transition was triggered). Condition: Incremented by one in the best cell in the source active set, when a Physical Channel Reconfiguration message is sent to the UE for an attempted hard hardover to an HS-DSCH cell that has a coverage relation to a cell in the active set, during Serving HS-DSCH Cell Selection. The best cell is the cell with the highest measured quality as defined by UeMeasControl::hsQualityEstimate. Counter type: PEG Scanner: Not included in any predefined scanner Counter is reset after measurement period: Yes Counter context: SRNC, DRNC if IurLink::srncPmReporting = ON in SRNC pmEnableHsHhoSuccess Number of successful hard handovers to an HS-DSCH cell, for which this cell was the best cell in the target active set (the active set when the transition was concluded). Condition: Incremented by one in the best cell in the target active set, when a Physical Channel Reconfiguration Complete message is received from the UE during an attempted hard handover to an HS-DSCH cell that has a coverage relation to a cell in the active set, during Serving HS-DSCH Cell Selection. The best cell is the cell with the highest measured quality as defined by UeMeasControl::hsQualityEstimate. Counter type: PEG Scanner: Not included in any predefined scanner Counter is reset after measurement period: YesCounter context: SRNC, DRNC if IurLink::srncPmReporting = ON in SRNC pmEnableEulHhoAttempt Number of attempted hard handovers to an E-DCH cell, for which this cell was the best cell in the source active set (the active set when the transition was triggered). Condition: Incremented by one in the best cell in the source active set, when a Physical Channel Reconfiguration message is sent to the UE for an attempted hard hardover to an E-DCH cell that has a coverage relation to a cell in the active set, during Serving E-DCH/HS-DSCH Cell Selection. The best cell is the cell with the highest measured quality as defined by UeMeasControl::hsQualityEstimate. For Multi Carrier connections, this counter is incremented only if this cell is a serving HS-DSCH cell. Counter type: PEG Scanner: Not included in any predefined scanner Counter is reset after measurement period: Yes Counter context: SRNC, DRNC if IurLink::srncPmReporting = ON in SRNC pmEnableEulHhoSuccess Number of successful hard handovers to an E-DCH cell, for which this cell was the best cell in the target active set (the active set when the transition was concluded). Condition: Incremented by one in the best cell in the target active set, when a Physical Channel Reconfiguration Complete message is received from the UE during an attempted hard handover to an E-DCH cell that has a coverage relation to a cell in the active set, during Serving E-DCH/HS-DSCH Cell Selection. The best cell is the cell with the highest measured quality as defined by UeMeasControl::hsQualityEstimate. For Multi Carrier connections, this counter is incremented only if this cell is a serving HS-DSCH cell. Counter type: PEG Scanner: Not included in any predefined scanner Counter is reset after measurement period: Yes Counter context: SRNC, DRNC if IurLink::srncPmReporting = ON in SRNC Soft HO Soft HO Counters pmNoTimesCellFailAddToActSet Number of times that a cell could not be added to the active set of a UE. Condition: Incremented by one in the target cell (the cell that could not be added to the active set), when any of the following occurs during an attempt to add an radio link: admission is not granted it is not possible to allocate a downlink channelization code the RNC receives an NBAP Radio Link Setup Failure message from the RBS, indicating that the Radio Link Setup procedure failed the RNC receives an NBAP Radio Link Addition Failure message from the RBS, indicating that the Radio Link Addition procedure failed the Radio Link Setup or Radio Link Addition procedure times out in the RBS the RNC receives an RRC Active Set Update Failure message from the UE, indicating that the Active Set Update procedure failed the Active Set Update procedure times out in the UE. pmRlAddAttemptsBestCellSpeech Number of attempted radio link additions for calls that included any CS Conversational Speech RAB (including AMR Single-mode 12.2, AMR-NB Multi-mode single- and multi-rate, and AMR-WB). Condition: Incremented by one in the best cell in the active set when an attempt is made to add a new RL to the active set or to replace an RL in the active set, for a call that includes a CS Conversational Speech RAB. The counter is incremented after a handover proposal from the handover evaluation function or after the RNC receives an RNSAP Radio Link Addition Request message IRAT_HO Neighbor Edit GSM relation Selection priority Audit was done for one RNC based on: • 2G to 2G attempts • The IRAT relation Audit There are improvements in Speech Drop Rate and IRAT HO/CC Success rate both with and without relocation 3G Neighbors (2G and 3G) 3G neighbor checking in 2G The 2G commands shows the cells which are defined for 3G cell cr RncFunction=1,UtranCell=7097XC1,utranrelation=7097XC1_7096XA1 utrancell=7096XA1 compressed mode • It also known as the Slotted Mode, is needed when making measurements on another frequency (inter-frequency) or on a different radio technology (inter-RAT). In the Compressed Mode the transmission and reception are stopped for a short time and the measurements are performed on other frequency or RAT in that time. After the time is over the transmission and reception resumes. To make sure that the data is not lost, the data is compressed in the frame making empty space where measurements can be performed. 1 to 7 slots per frame can be allocated for the UE to perform this intra frequency (hard handover) For one RNC , which had the highest number of congested 2G cells which had an active co-sited 3G cell, we have changed the compress Mode triggering thresholds for both RSCP and EcNo which has resulted in increased speech traffic retention on 3G and reduction in IRAT per call for the RNC Compressed Mode trigger (event 2D) threshold for RSCP and EcNo were relaxed from -95 to -102 and from -12 to -13 respectively Compressed Mode Modifying the 2D parameters (Compressed Mode trigger threshold ) 2d thresholds were changed in one RNC on 23rd August. below shows the summary of the results: Speech traffic increased by almost 35%. Parameter usedFreqThresh2dEcno No visible impact on CSSR and Throughput. usedFreqThresh2dRscp 30% reduction in IRAT HO attempts. Speech drop rate significantly improved because of reduced number of IRAT-related drops. Old -12 -95 New -13 -102 Find Worse Cell in RNC For seeing Propagation Delay • pmx . pmpropag Date: 2015-07-25 Sector=1,Carrier=1,Prach=1 pmPropagationDelay 464,27836,7444,129,0,0,2,1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0 Sector=1,Carrier=2,Prach=1 pmPropagationDelay 464,32678,8963,46,0,0,0,0,0,0,0,29,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0 Sector=3,Carrier=1,Prach=1 pmPropagationDelay 464,16388,3955,1,0,0,1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0 Sector=3,Carrier=2,Prach=1 pmPropagationDelay 464,19812,5413,13,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0 Sector=4,Carrier=1,Prach=1 pmPropagationDelay 464,36250,767,10,16,0,5,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0 • Another one (Has overshooting) Sector=1,Carrier=1,Prach=1 pmPropagationDelay 464,6025,6359,3636,3577,295,325,27,86,47,63,9,20,48,23,11,64,4,132,0,2,0,6,2,1,3,12,9,8,6,0,0,0,0,0,0,0,0,0,0,0 Sector=1,Carrier=2,Prach=1 pmPropagationDelay 464,4500,16025,7645,5416,248,430,31,18,84,18,9,21,65,2,6,60,23,180,1,3,2,5,2,0,16,19,2,2,0,0,0,1,0,0,0,0,0,0,0,0 Sector=2,Carrier=1,Prach=1 pmPropagationDelay 464,2867,7607,6746,4605,3818,2922,1850,96,48,793,2441,77,2,2,0,1,1,0,0,0,0,0,2,0,0,0,0,0,0,0,0,0,0,0,1,0,0,0,0,0 Sector=2,Carrier=2,Prach=1 pmPropagationDelay 464,6499,12448,3527,4205,2455,1048,1654,153,161,820,1977,20,0,36,1,2,0,0,0,0,0,0,1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0 Sector=3,Carrier=1,Prach=1 pmPropagationDelay 464,4349,3039,5249,4329,121,189,113,117,244,23,22,40,123,230,140,30,32,45,1,0,24,0,1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0 Sector=3,Carrier=2,Prach=1 pmPropagationDelay 464,2619,5857,2568,7619,218,219,385,149,26,31,29,6,72,239,48,26,46,28,0,17,6,0,1,1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0 For seeing type and configuration (Tilt) of antenna The productNo. Command showe the type of RET, and also the Aretdevicedata showe the type of antenna which set for the specific RET Change Tilt Cell Power With the following commands we can find the power license, maximum power for cells and cell’s power Command: set RbsSubrack=RUW1,RbsSlot=13,AuxPlugInUnit=RUW-1,DeviceGroup=RUW,TpaDeviceSet=1,TpaDevice=1 maxTotalOutputPower 80 For tracing NodeB implemented commands Find Scrambling code Power Expansion 1300 For cell expansion we have taken into consideration: • 1100 969 978 20150907 1000 900 800 700 675 672 600 583 586 20150831 610 625 626 20150902 634 20150901 700 20150830 The list can be prioritized into 3 categories 1) Cells with less than 500 Kbps 2) between 500 kbps and 800 kbps 3) greater than 800 kbps 1200 20150906 • • HS power Utilization (more than 90%), HS Users (RABs), And the user Throughput 1,216 597 500 20150908 20150905 20150904 20150903 20150829 20150828 20150827 Standardization of Primary CPICH Power 1. All cell with CPICH power below 320 were analyzed for a) b) c) d) 2. Power utilization, Admission rejections, Overshooting, RET status. CPICH power for these cells were increased in steps of 1dB until: a) They were increased to 320 b) They were limited by power utilization c) They encountered the resource rejection 3. 4. Impact of this activity on KPIs, Power utilization , Compressed Mode and Throughput has been shown in this slide Some required changes must be implemented for remaining cells. a) Down tilt Required (RET not installed) b) New site required c) Power Expansion Required d) UL CE Expansion required Print CPICH power (get XXX primarycpich) Print CPICH power (get XXX primarycpich) High-Speed Shared Control Channel HS-SCCH And Its Work In 3G WCDMA Carries physical layer signaling to a single UE, such as modulation scheme (1 bit), channelization code set (7 bit), transport block size (6bit), HARQ process number (3bit), redundancy version (3bit), new data indicator (1bit), UE identity (16bit) HS-SCCH is a fixed rate (60 kbps, SF=128) downlink physical channel used to carry downlink signaling related to HS-DSCH transmission HS-SCCH High-Speed Shared Control Channel is an added channel to UMTS to increase downlink data rates. This is defined in Release 5 of the UMTS specifications. It is also part of the HSDPA. HS-SCCH uses a SF=128 and has q time structure based on a sub-frame of length 2 ms, i.e. the same length as the HS-DSCH TTI. The timing of HS-SCCH starts two slots prior to the start of the HS-PDSCH sub frame. The following 7 items information is carried on the HS-SCCH • Modulation scheme(1bit) QPSK or 16QAM • Channelization code set (7bits) • Transport block size ( 6bits) • HARQ process number (3bits) • Redundancy version (3bits) • New Data Indicator (1bit) • UE identity (16 bits) In each 2 ms interval corresponding to one HS-DSCH TTI, one HS-SCCH carries physical-layer signaling to a single UE. As there should be a possibility for HS-DSCH transmission to multiple users in parallel (code multiplex), multiplex HS-SCCH may be needed in a cell. The specification allows for up to four HS-SCCHs as seen from a UE point of view .i.e. UE must be able to decode four HS-SCCH. Does this site need DL CE expansion as it’s having high DLHW expansion The site has the following issues • high rejection of RRC connection due to high MP load • CSSR_PS • CSSR_Speach • RRC request denied First Step The two Neighbors with qrxlevmin = -105 , hence the base line value is -111 , so traffic pushed to our site and it is the major reason of 8089 congestion hence CE expansion done. And also 60W activated , also 8563X & 1934 carrying very low traffic hence • Changed qrxlevmin of neighbors to -111 • and also if it is possible try to balance the traffic by Up-tilting Second Step But the site has a few Overshooting and covers 5Km For Reducing IRAT HO form 3G2G IUB IUB Congestion Iub congestion is a common reason for high number of failures after admission events. Depending on the volume of traffic per service or RAB, certain QoS could be congested at the AAL2: All RABs excluding HSDPA are configured to use Class A or Class B being these two mostly impacted by congestion. Most of the time Class B is the first QoS to get congested leading to failures after admission events. • Possible indicators : • • • Check for congestion at the Iub link (See below) Check for E1 issues and history of alarms of E1s (for intermittent E1 alarms) Possible solutions for Iub congestion : • • • • Enable Directed retry (short term solution). Correct possible AAL2 miss configuration at Node B, RNC and RXI (AAL2 profile must match in all entities) Order new E1s (long term solution). Change AAL2 QoS configuration depending on services request volume (CS voice, R99 data, HSDPA, etc). • Low RRC Success Rate or Low RAB Success Rate In case a poor RRC Success Rate is detected and neither Admission Blocks nor MP Load rejections can explain such a degradation of the RRC Accessibility, then check these 2 counters: pmNoRrcConnReqBlockTnCs RRC CS failures due to congestion on the user plane (AAL2) or control plane (UniSaal or SCTP) of the transport network. pmNoRrcConnReqBlockTnPs RRC PS failures due to congestion on the user plane (AAL2) or control plane (UniSaal or SCTP) of the transport network. IUB Congestion City City 1 City 1 City 1 City 1 Site Site 1 Site 2 Site 3 Site 4 IUB Unavailability pmTotalTimeIubLinkCongest pmNoOfDiscardedNbapcMessages pmNoFailedAfterAdm edDl 437868 262488 391 170304 59808 192 165246 70926 223 161658 69114 212 IUB Congestion IubLinks/AbisLinks Status str[12ft] Print status of the IubLinks/AbisLinks and their associated Cells and Channels RNCE1> str 151201-17:12:33 10.139.153.16 11.0b RNC_NODE_MODEL_V_3_4701 stopfile=/tmp/28429 0% ~50% ~100% MOD IUBLINK CELLNAMES CFRPHEU1 CFRPHEU2 CFRPHEU3 CFRPHEU4 CFRPHEU5 CFRPHEU6 ICDS TN TNPORTS --------------------------------------------------------------------------------------------------------------------1054 Iub_UE1773X UE1773XA-1/1/1/2/2/2 111111 111111 111111 111111 111111 111111 1111 I 1055 Iub_UT9727X UT9727XA-1/1/1/2/2/2 111111 111111 111111 111111 111111 111111 1111 I 1064 Iub_UT7479X UT7479XA-1/1/1/2/2/2 111111 111111 111111 111111 111111 111111 1111 I 1065 Iub_UT9624X UT9624XA-1/1/1/2/2/2 111111 111111 111111 111111 111111 111111 1111 I 1085 Iub_UT9852X UT9852XA-1/1/1/2/2/2 111111 111111 111111 111111 111111 111111 1111 I 1094 Iub_UT9827X%1 UT9827XA-1/1/1/1/2/2 111111 111111 111111 111111 111111 111111 1111 I 1094 Iub_UT9827X%2 UT9827XC-2/2 111111 111111 1111 I ollowing 42 sites are totally or partially unavailable: --------------------------------------------------------------------------------------------------------------------MOD IUBLINK CELLNAMES CFRPHEU1 CFRPHEU2 CFRPHEU3 CFRPHEU4 CFRPHEU5 CFRPHEU6 ICDS TN TNPORTS --------------------------------------------------------------------------------------------------------------------3106 Iub_UT0320Z UT0320ZA-1/2 L000LL L000LL L000 I 3136 Iub_UT7029X UT7029XA-1/1/1/2/2/2 L000LL L000LL L000LL L000LL L000LL L000LL L000 I 3155 Iub_UT9123X UT9123XA-1/1/1/2/2/2 LLLLLL LLLLLL LLLLLL LLLLLL LLLLLL LLLLLL L000 I --------------------------------------------------------------------------------------------------------------------Cell availability: 920 of 1148 cells are up (80.1 %) Site availability: 155 of 197 sites are fully operational (78.7 %) Unlocked Cell availability: 920 of 942 unlocked cells are up (97.7 %) HS availability: 920 of 1148 channels are up (80.1 %) EUL availability: 920 of 1148 channels are up (80.1 %) Iub/link problems It was a specific case with severe degradation observed at busy hr. also observed Iub discards & HS Cap limiting ratio at same times on impact of degradation NBAP • In the 3GPP UTRAN architecture, NBAP (Node B Application Part) is the signaling protocol responsible for the control of the Node B by the RNC. NBAP is subdivided into Common and Dedicated NBAP (C-NBAP and D-NBAP), where Common NBAP controls overall Node B functionality, and Dedicated NBAP controls radio links to specific UE. NBAP forms part of the Iub interface. • Example 1: High Failures after Admission on Multiple sites in specific location due to possible transport congestion as these sites also have high NBAP discards • Command in RNC (NBAP Discard) • High NBAP discards cause: • MPload rejections • DL Hw rejections, DL code rejections, • DL power rejections, • UL HW rejections NTP Server Reachability Fault Alarm (1) • Alarm Cause – IP network problems (The traffic on the network is disturbed. This can be caused by high traffic load or a hardware fault. – Communication problems toward NTP server Unable to communicate with NTP server (due to misconfiguration or because the NTP server is disabled.) – Wrong IP address (IP address is invalid or it points to a host that is not an NTP server.) – DNS problems The DNS is not performing its task in translating domain names into valid, up-to-date IP addresses. – Wrong domain name DN (domain name) cannot be resolved, DN resolved to a host that is not an NTP server, DN resolved to a non-existent host NTP Server Reachability Fault Alarm (2) The alarm is issued when a Network Time Protocol (NTP) client detects a ‘‘not reachability’’ condition toward an NTP Server, which has been configured as an IP synchronization reference. Impact: No impact on traffic, if there is a working standby synchronization reference. Otherwise, the Traffic disturbances. NTP Server Reachability Fault Alarm (3) The HSDPA concept is based on the following features: • • • • • • Shared channel transmission Higher-order modulation Short transmission time interval (TTI) Fast link adaptation Fast scheduling Fast hybrid automatic-repeat-request (ARQ). HSDPA Scheduling The HSDCPA channel is a shared channel that can be shared in time using its 2 msec Transmission time interval (TTI) and codes where the SF 16 codes available for HSDPA can be shared between up to 4 users in one TTI EUL Channels • Uplink HSUPA channels A variety of new channels have been introduced for HSUPA to enable the system to carry the high speed data. These new channels are: – E-DCH, the Enhanced Dedicated Channel: This HSUPA uplink channel carries on block of data for each TTI (Transmission Time Interval). The E-DCH can be configured simultaneously with one or more DCHs. In this way high speed data transmission can occur at the same time and on the same UE as services that use the standard DCH. As a low latency (delay) is one of the key requirements for the high speed uplink a short TTI (Transmission Time Interval) of 2 ms is supported in addition to one of 10 ms. The short TTI allows for rapid adaptation of transmission parameters and it reduces the enduser delays. There is a balance to be determined for the TTI. It is found that the physical layer processing is proportional to the amount of data to be processed, and accordingly the shorter the TTI the lower the level of data per TTI. However for applications requiring relatively low data rates, the overheads required with a 2 ms TTI may be unduly high. In these circumstances a longer TTI is more appropriate. – – The E-DCH is mapped to a set of E-DCH Dedicated Physical Data Channels. E-DPDCH (Enhanced Dedicated Physical Data Channel): This HSUPA uplink channel carries uplink user data. Each UE can transmit up to four E-DPDCH channels at a spreading factor of SF256 to SF2. The number of E-DPDCHs s and their spreading factors are varied according to the instantaneous data rate required. As an example of a typical scenario, to achieve a 2 Mbps rate - the raw data rate of early devices - two SF2 EDPDCHs were required. E-DPCCH (Enhanced Dedicated Physical Control Channel): This HSUPA channel carries the control data required by the Node B to decode the uplink channels including the EDCH Transport Format Combination Indicator which indicates the block size, retransmission sequence number, etc. • Downlink HSUPA channels A variety of new channels have been introduced for HSUPA to enable the system to carry the high speed data. These new channels are: • E-AGCH (Enhanced Absolute Grant Channel): This HSUPA channel provides the absolute limit of the power resources, i.e. the serving grant, that the UE may use. The channel is used to send scheduling grants from the scheduler to the UE to control when and what data rate the UE should be used. The E-AGCH is only sent by one NodeB regardless of the number that the UE is communicating with. The NodeB used is the one that has the main responsibility for the scheduling operation. The E-AGCH is typically used for large changes in data rate. • E-RGCH (Enhanced Relative Grant Channel): This channel is used to move the UE serving grant up, down or remain the same. This HSUPA channel is generally used for relatively small changes during an ongoing data transmission. Large changes are handled by the EAGCH. • E-HICH (Enhanced DCH Hybrid ARQ Indicator Channel): This HSUPA channel is used to provide the acknowledgement of the UE data received by the Node B. Paging Paging Process A paging message for a CS call to a certain UE is broadcasted to all cells belonging to the LA in which the UE is registered. Accordingly, a paging message for a PS connection is broadcasted to all cells in the RA in which the UE is registered. Paging is initiated upon request from the CN or triggered in UTRAN. • UE terminating service request for PS or CS services (CN initiated). CN initiated paging is applicable to UEs in idle mode. • UTRAN initiated broadcast to inform UEs when System Information is modified. UTRAN initiated paging is used whenever System Information (e.g. information about cell selection/ reselection, addition/replacement of neighbors, handover etc.) has been updated. The paging record varies in length depending on whether it includes the UE identity in terms of IMSI, TMSI, or P-TMSI. A PCH frame can carry one “Paging Type 1” message of 10 ms and may contain between 3-5 paging records, depending on whether the paging uses IMSI or TMSI/P-TMSI. When the UE mode is Cell_FACH or Cell_DCH common or dedicated physical channels are already in use and the paging message “Paging Type 2” will be used. the paging attempts on the LAC went to almost zero for few hours when the issue started and BH attempts have doubled since then. It seems that any activity/change was done in Core on the mentioned date SDATE INTERVAL NE CN INIT PAGING TO IDLE UE LA 07-Nov-15 07-Nov-15 07-Nov-15 AH AH AH RNCE2 RNCE1 RNCE3 4,910,031 5,298,166 4,325,182 CN INIT PAGING TO IDLE UE CN INIT PAGING TO IDLE UE RA 0 0 0 11,414,735 13,442,153 9,273,015 CN INIT PAGING TO URA UE UTRAN INIT PAGING TO URA UE UTRAN Paging Rejection 1,326 365 96 Battery test basic feature activation ? HSDPA Flexible Scheduler Features for improving the Throughput Benefits This feature provides the flexibility of trading system capacity with fairness among users on cell level Description The scheduler transmits information to users on a per 2 ms TTI (Transmission Time Interval) basis. Several aspects are considered when deciding which Ues to transmit to. These aspects include: • UE radio channel measurements, CQI (Channel Quality Indication), with the potential of increasing system capacity by favouring users with good radio condition. • Delay and average bit rate, with the potential of increasing fairness among users. • Re-transmission, with the potential of favouring users with scheduled retransmissions Parameters: The flexible scheduler is operator configurable on cell level to one of the following strategies: • Max CQI • Proportional Fair - low fairness • Proportional Fair - medium fairness • Proportional Fair - high fairness Round Robin (does not need Flexible Scheduler) • Equal bit rate o Flexible Scheduler is a pre-requisite for Code Multiplexing and HSSCCH Power Control optional feature Summary HSDPA Code Multiplexing and HSSCCH Power Control Features for improving the Throughput Code multiplexing is a complementary method to time multiplexing (which was introduced in P4) that gives the possibility to share the HS-DSCH resource among users in both code and time domain, thereby improving the overall performance in terms of system throughput and number of users served at a given delay HS-SCCH power control reduces the RBS output power needed for the HSSCCHs and thereby increases the system capacity. Description Code multiplexing is a complementary method to time multiplexing that gives the possibility to share the HS-DSCH resource among users in both code and time domain. The scheduler can transmit information to up to 4 users per 2 ms TTI (Transmission Time Interval) by using separate codes, or group of codes, per user. The codes to be received by a certain UE are signalled on HS-SCCH. HS-SCCH power control exploits e.g. UE measurements to adapt the HSSCCH output power. In this way, users close to the RBS will have less HSSCCH output than users far away from the RBS. The overall target is to reduce the average RBS output power needed for the HS-SCCHs. As such, the HSSCCH power control gain increases with the allowed number of users per TTI, c.f. code multiplexing. Parameters It will be possible for the operator to control: • The number of HS-SCCHs for code multiplexing • Operation of HS-SCCH power control by suitable parameters such as minimum and maximum HS-SCCH output power as well as update rate. Benefits This feature • Improves the delay characteristics, especially for users downloading small objects, e.g. Web pages • Improves the system throughput • Reduces RBS output power for HS-SCCH signaling Interference Suppression The Interference Suppression is an advanced receiver enhancement for DUW. It brings significant performance gains for EUL, which in turn lowers interference levels also for other radio bearers. Interference Suppression is supported in deployment scenarios with 1, 2, or 4 receiver antennas. The Interference Suppression receiver replaces the existing G-Rake receiver and improves equalization, SIR estimation, and interference suppression (interference mitigation) capabilities. The NodeBFunction::featureStateInterferenceSuppression attribute controls whether the feature is enabled. The Interference Suppression licenses is required. This feature is only available for DU-based RBS. EUL 2ms TTI increase The EUL 2ms Transmission Time Interval (TTI) feature provides: • higher uplink bit rates • lower latency. The NodeBFunction::featureStateEul2msTti attribute controls whether the feature is enabled. The EUL 2ms TTI license is required. Candidate RNC must has the following circumstances: • Good number of average EUL best users • Good UL RSSI • Minimum UL hardware admissions 2ms TTI users admission The 2ms TTI users admission increase from 4 to 12. Overall we have increase in both Cell and User Throughput which increase in UL CEL utilization, both static and dynamic Moatch cd mobatch ls Cell Disable due to RncNotAbleToScheduleSibs alarm • Issue is related to wrong relation plan. There was relation creation and cell parameter Unbalance MaxTotalOutputPower in RRUS 12 CE congestion The CE congestion suffers this site. The overshoot and capacities (as below) were checked. There is not overshooting . Finally it should be reduced the TTI2 from 6 to 4 SHO degradation due to many alarms Direct Retry IRAT HO high rejections due to overshooting • IRAT affected due to increasing attempts of directed retry due to power congestion in some cpichpower increased sites CE congestion Issue after expansion Power Congestion The mentioned site encounters the PWR Congestion, after expansion it suffers the CE Congestion. After Expansion the site encounter the CE Congestion The ulHwAdm must be set at high level (99) Sometimes the RbsChannelElementsUplink has low value and the ULHW must be expand High UL RSSI Issue: The UL RSSI reading on Node B is high (ranging -70 to -80 dBm) while normally should be -100 to -108 Causes: • Subscriber behavior (UE with high RSSI) • interfered area by RF signal (jammer) • Tx link fluctuation • Congested Transmission Link • TMA is installed but it is not defined • when it is accompanied by abnormal Drops and there is nothing to suggest bad radio conditions such as overshooting, there is a high possibility that it has got some Rx path hardware issue • • In last case, this is generally rectified by the site engineer, replacing the faulty RU, feeder, antenna etc. non-traffic interference • High TX power from a UE that are connected to a far cell. This can happen due to missing neighbors RTWP Vs. RSSI High UL-RSSI due to missing Neighbors The site’s cells suffer the high UL-RSSI in general but at 15th Nov. it enhanced more. It re-homed from BSC to another one in 2G part at that time, and also the IRAT HO with relocation has degraded. the inter system relation definition should be revised. High UL-RSSI due to Congested link Link between two sites is congested and causing low RSSI DL traffic ps16 and ps128 has been increased on RNC One site had very high DL H/W congestion and almost no HS/Eul traffic since the 7th. CV has been re loaded and is now taking Eul/HS traffic. Payload and throughput degrade due to UGW An issue with UGW which has affected both 3G as well as 2G’s payload and throughput. All UGWs affected in Region due to possible Gi Interface issue Alarm that affect Traffic Sector C is not taking any traffic and has the following alarm Date & Time (Local) S Specific Problem MO (Cause/AdditionalInfo) ==================================================================================================================== 2014-11-28 07:09:40 C License Key File Fault Licensing=1 (No license key file installed. IntegrationUnlock=ACTIVATED, 16 days remaining) 2014-11-28 07:09:52 m InconsistentConfiguration Subrack=1,Slot=1,PlugInUnit=1,EcPort=1 (Attribute hubPosition is empty or not valid) 2014-11-28 07:12:18 M DigitalCable_CableFailure DigitalCable=3_1_RI_C (DN2: SubNetwork=ONRM_ROOT_MO_R,SubNetwork=RNCE2,MeContext=1601X,ManagedElement=1,Equipment=1,Subrack=1,Slot=1,PlugInUnit=1,PiuDevice=1,DeviceGroup=DUI DN3: SubNetwork=ONRM_ROOT_MO_R,SubNetwork=RNCE2,MeContext=1601X,ManagedElement=1,Equipment=1,SectorAntenna=3-1,AuxPlugInUnit=RRUW-1,RruDeviceGroup=1) 2014-11-28 10:08:51 M NTP System Time Sync Fault ManagedElementData=1 (additionalInfo: NTP general problem) Case: Speech Drop Issue: High speech drops on one site due to overshooting Solution: RET installation has been requested. CPICH power reduced by 1 dB temporarily DCR HS DCR HS degraded due to hardware issues in a site, specifically alarms such as temperature exceptionally high and Piu conn lost are toggling. Emergency License This site has very high power congestion since it came on. As it’s on Emergency license. 80 watts for sector C and 60 for the others have been activated . Request for 60 Watt expansion for ll sectors as it will again be congested once the EM License expires. In addition to the power admission for Sector C has been increased to 95. In site life we can use only 2 times MP Load The module MP handles signaling associated with traffic events. Connection setup and release (Speech, PS R99, HS, LA update, SMS). RncModule: Create this MO on the MP to group IubLinks in a way to minimize inter-processor communication variations in packet delay along the path, i.e. packet delay variation (PDV), also impacts accuracy (Synchronization Ericsson WCDMA doc) Total number of pages discarded due to central MP load control for a RNC pmNoPageDiscardCmpLoadC Subrack Identity Local Distinguished Name Description Main Subrack ManagedElement=1,Equipment=1,Subrack=MS The MS in an RNC. Extension Subrack ManagedElement=1,Equipment=1,Subrack=ES-2 The 2nd ES in an RNC. Slot in MS ManagedElement=1,Equipment=1,Subrack=MS,Slot=7 The 7th board in the MS. Slot in ES-2 ManagedElement=1,Equipment=1,Subrack=ES2,Slot=12 The 12th board in the second ES UtranCell=7105XC2 pmNoRejRrcConnMpLoadC 15847 UtranCell=7105XC1 pmNoRejRrcConnMpLoadC 15444 UtranCell=7105XB2 pmNoRejRrcConnMpLoadC 14532 UtranCell=7105XB1 pmNoRejRrcConnMpLoadC 13764 UtranCell=7105XA2 pmNoRejRrcConnMpLoadC 9979 • Load control refers to the RNC MP load • MP implements overload protection • Load control applies prior to RL setup (subject to RN AC) • If MP load exceeds 85%, RRC setup requests are rejected • MP load: observed with counters of the LoadControl MOC • Failures due to MP load: pmNoRejRrcConnMpLoadC Device failure high failures after admission on multiple sites occurred Device ES-1-11 and ES-2-16 locked and issue has recovered. NBs which are attached to particular device will be automatically be shifted to other active devices. But definitely if the MP load on other devices will increase and if the other devices are already on a high load, it might result in MP load rejection on that particular device, that’s why its always recommended to check the RNC MP load before locking any devie. lget iublink=iub. rncmodule lget iublink=iub. rncmodule RncModule=ES-2-17-4 Co-Scrambling Code Two Sites have the Same Scrambling code for all Cells (all sectors have primaryScramblingCode=0) After changing the Scrambling code, the improvements have achieved. CSSR_PS due to MPLOAD high traffic sites and DL CE congestion has increased after URA implementation. For Cope with the DL CE in site level • change dlHwAdm to 99, sf16Adm to 0 • sf16gAdm to 0 RRC level code congestion (pmNoRrcreqdeniedAdmDlChanlCode) numhsscchcodes (34) increased RNC>get UtranCell=1805XA1, numHsScchCodes Definition??? dlcodeadm (90 99) RNC> get 1805 dlcodeadm Definition??? Speech Drops due to Power Congestion The releaseAseDl parameter minimizes the speech drops caused by DL power congestion Parameter Description: Amount of ASE in the downlink to be released with each periodic congestion-resolution action targeting the guaranteed traffic class connections in this cell. 0 indicates that no ASE is released for guaranteed traffic class connections. This prevents congestion-resolution actions on the guaranteed traffic class connections in the cell. Range: 0 to 500, Default=1 Changing the value from default 1 to 0 means, now congestion control will not release a guaranteed traffic class connection. The releaseAseDlNg uses for the non-guaranteed traffic UL Sync Drops This specific cell is suffering from high UL Sync drops since the 26th with loss of traffic. The delta between RSSI in Sector C for carrier 1 which is ~10 dB . We must arrange to visit the site. pmNoSysRelSpeechUlSynch Number of system disconnections due to lost uplink synch for calls that included any CS Conversational Speech RAB (including AMR Single-mode 12.2, AMR-NB Multi-mode single- and multi-rate, and AMR-WB). Condition: Incremented by one in the best cell in the active set prior to the call release, when a CS Conversational Speech call is released by the network after expiry of the timer defined by Rrc::dchRcLostT. LKF (License Key File) CSSR degradation due to frame lost Site having transmission problems. The PM counter counts lost or discarded HS-DSCH data frames in RBS. For instance, Spi02 is valid for scheduling priority class 02 The SPI and GBR are the two primary parameters that can be used to control the QoS differentiations on HSDPA. The GBR can be set for a user with minimum target bit rate while the SPI can be set to give priority to data flow to achieve that target. HS Frame Lost due to IuB congestion high Iub HS/EUL capacity limitations & HS Frames Lost RNC RNCE2 RNCE2 RNCE2 RNCE2 RNCE2 Sie 9519X 7557X 9747X 7062X 7042X Average of MAX(PMCAPALLOCIUBHSLRSPI01) 87.5 86 85.5 85.66666667 85.66666667 Average of EUL_LIMITING_RATIO 0.00 0.00 0.00 0.05 0.00 Average of HS_FRAMES_LOST_RATIO 22.50% 21.17% 21.15% 21.10% 20.64% Check the Max and Min Tilt for calibration Calibrating the RET A calibration of the RET is performed to find the limits of the antenna tilt and the actuator is driven through the whole tilt range of the controlled antenna element. Before calibrating an RET, a connection to the ARETU or RETU must be established. To calibrate an RET, start the action forceCalibration in the RetDevice MO. Cabinet change activity on site (Discrepancies in R99 ADM parameters) Baseline settings were changed by Field team during DUW change activity • Maxnumeulusers • Maxnumhsdpausers • NumHsPdschCodes • Maxtotaloutput power RNC Wrong Values Correct Values sf128A dm incons. Count sf16Ad m incons. Count sf16Ad m UL incons. Count sf16gA dm incons. Count sf32Ad m incons. Count sf4Ad m incons. Count sf64Ad mul incons. Count sf8Ad m incons. Count sf8Ad mul incons. Count sf8gAd mul incons. Count 0 42 48 48 0 54 0 12 32 32 128 0 32 16 32 0 100 0 0 0 ############################################################################### MO Class Attribute Type Flags ############################################################################### UtranCell sf128Adm long -----------------------------------------------------------------------------------------------------------------------------------Admission limit for non-guaranteed traffic class connections with downlink Spreading Factor (SF) = 128. This is the maximum number of radio links with SF=128 in the downlink for which new admission requests for non-guaranteed traffic classes will continue to be allowed. Reaching or exceeding this number of downlink SF=128 radio links (for non-guaranteed service classes) will block setup in this cell of more non-guaranteed traffic class radio links that would require downlink SF=128. Note that for this particular admission limit, soft and softer handovers are not blocked (though inter-frequency handovers may be blocked). The value 128 disables the admission policy, meaning that no blocking of downlink SF=128 requests will occur. Change takes effect: Immediately Range: 0 to 128, Default=128 HS average Number of UE in Queue HsAqmCongCtrlLicenseNotValid alarm: When this alarm is generated and license key is disable, the cell configured for AQM based Congestion Control for HSDPA is not possible to setup. pmSumNonEmptyUserBuffers HS_AVG_NO_UE_IN_QUEUE = (pmNoActiveSubFrames + pmNoInactiveRequiredSubFrames) CommunicationLostWithRet alarm By this alarm you cannot change the electrical tilt This alarm will generally require an RE to go to site. Communication with the ASC/RET is lost. The consequence of this alarm is that planning/optimization will be unable to make a tilt change to the affected sector. Connection with the RET will need to be restored on site or a replacement ASC will be needed. RBS (actions): • Alt *show current alarms • lga | grep AuxPlugInUnit_CommunicationLostWithRet *show history of current alarm • get radio no *confirm if node is carrying traffic • st plug *print state of all plug in units • Prox *do a get on the disabled proxy number • Get ret electrical • acl xxx *check what action you can perform on the proxy number • acc xxx restartAuxUnit *try restart the ASC/RET using the proxy number RNC (Action): • moshell XXRNCX *log onto the RNC • lt all *load all Managed Objects • alt *show current alarms • lst .xxxx *show status of channels failed After ADM Carrier_SignalNotReceivedWithinTime alarm Site Down (TxDeviceGroup_GeneralSwError) The likely causes of this alarm are the following: • A software fault • An incorrect version of the software • A faulty configuration, depending on a software error (only when RruDeviceGroup issues the alarm) In this case it is the TX board that has the problem. As a consequence the capacity of the site is decreased. • RBS: – – – – – alt *show current alarms cab *confirm the TX boards on the site st plug *check the state of the TX boards acl xxx *check what action you can perform on the board using the proxy number acc xxx manualRestart *try restart the board Check that the alarm has cleared. If the alarm is still present an RE will need to go to site and do a hard reset or change the TX board. Confirm the site is carrying traffic. CSSR Degradation High failed-after-adm at two NBs; suspected TXN issue (PDV alarm) Code Congestion It recovered after RBS reset High power congestion in site due to RRU Attenuation Discrepancy Affect of PWR congestion on IRAT and SHO The PWR congestion is not very affective on IRAT but in SHO is affective CSSR-DCR degradation Site performance degraded due to false configurations 1) get . licensecap 2) get . dlatten 3)get . maxtot 4) get . maxdlpower maxDlPowerCapability=maxTotalOutputPower dlAttenuation For instance: 80 wat per cell, 40 watt per carrier (=46 dBm) Then maxDlPowerCapability (460-7=453) Find the type of DU and RU, Temp, VSWR and Board Serial No. Find VSWR Frame Synchronization In the downlink direction, frames are synchronized in order to be transmitted in the air interface at a certain transmission time. The Frame Synchronization function also provides a base for macrodiversity functionality. Frame transport timing is supported within a Serving Radio Network System (SRNS) as well as between two RNSs. The Frame Synchronization function also provides timing and numbering of the traffic frames to be transported over the Iub interface between an RNC and its associated RBS. The function applies to R99 common channels FACH and PCH and dedicated channels R99 DCH. For the data transfer on RACH and BCH, there is no Frame Synchronization related functionality in the RNC. For HSDCH (HSPA channels), scheduling is the responsibility of the RBS, and thus the Frame Synchronization function is not used. High Failures after admission and Sector C has very high UL Sync drops and loss of traffic Alarm history: lga -a feeder disconnection and also synchronization issue was the major issue PS and CS CSSR Degradation? Due to wrong configuration The baseline script was run and some values are default and wrong BLER UL_BLER = 100 ∗ PMFAULTYTRANSPORTBLOCKSBCUL PMTRANSPORTBLOCKSBCUL pmTransportBlocksBcUl -----------------------------------Total number of uplink DCH transport blocks. Condition: Incremented by one for each valid transport block (based on the CRCI) received on UL DCH, before macro diversity combining. PMFAULTYTRANSPORTBLOCKSBCUL----------------------------------Total number of faulty uplink DCH transport blocks. BLER Degradation After activation of URA_PCH in RNCE the UL_BLER has degraded. UL_BLER = 100 ∗ PMFAULTYTRANSPORTBLOCKSBCUL PMTRANSPORTBLOCKSBCUL URA Update Success Rate (DUW Faulty) URA_UPDATE_SUCC = 100*(pmNoUraUpdSuccess/pmNoUraUpdAttempt) Failures after admission (CSSR/Soft HO) • • • • • • • • • • • • RU Fault TN Blocking Iub congestion NBAP Discards License expansion Carrier_SignalNotReceivedWithinTime alarm HW swap and CPRI cables NTP Server alarms (NTP Sync Faults alarms) Transmission Issue DUW faulty HW Alarms_LKF issue after 3rd carrier addition False configurations (maxDlPowerCapability) CSSR (Baseline parameter was not set correctly ) CSSR (CLOCK Synch alarms ) CSSR (CLOCK Calibration alarms) DCR Firstly the DUW was fault after investigation it found that the PSU was faulty and it’s replaced. Issue is rectified and DUW is working normally Low IRAT HO The IRATHO is poor due to the following issue 1. High ICM which is causing IRAT HO failures. 2. High TCH assignment failure rate which is also causing poor IRAT performance for 3G site. The following activities to be done to maintain and improve IRAT performance: • High Failure Relations deletion except Co-site. • SelectionPriority tuning based on succeeded IRAT attempts (detail information will be shared accordingly). • Periodic ExternalGsmCell definition audit • Penalizing poor performing GSM cells using individualoffset. (detail information will be shared accordingly). • Tuning the gsmAmountPropRepeat from 1 to 0. • Tuning the gsmThresh3a from -95 to -85 to attempt only in good radio conditions on GSM. Sleeping Cell Sleeping Cell 1 Cell is sleep due to SFP faulty (Small Form-factor Pluggable) Sleeping Cell 2 The cell is sleeping periodically due to RRUS faulty Sleeping Cell 3 Digital Cabling Fault Sleeping Cell 4 High VSWR Sleeping Cell 5 Tr device failures Sleeping Cell 6 The cell is not taking any traffic due to Carrier_RejectSignalFromHardware alarm Sleeping Cell 7 The cell is not taking any traffic due to high RSSI Sleeping Cell 8 Disable from RNC side DCR • • • • • • • • • • • • DUW is faulty RETU alarm Overshooting Digital cable failure alarm TX problem Iub congestion Code/User/Pwr Congestion RSSI PSU Faulty LKF issue RRUS faulty High VSWR Sectors are not propagating Sometimes the RRUs/RUs get freeze due to some internal processor failure or high temperature which is not always be visible via alarms. And it stops setting up new RRC connection. If you see when the RU stopped propagation it also stopped setting up new RRC connection. And finally the NodeB was restarted Give priority to neighbors based on GSM attempt Important parameter & counters details Capacity management • • • • compModeAdm: Absolute admission limit for the number of radio links in compressed mode in a cell. (15) dlCodeAdm: Parameter that defines in percentage the absolute admission limit for DL code usage (90, 95, 97) pwrAdm: Parameter that defines in percentage the absolute admission limit for DL power utilization. (85 or 95) sf8Adm: Defines the absolute admission limit for the number of RLs with SF=8 (PS384) in DL. (0) • sf16Adm: Defines the absolute admission limit for the number of RLs with SF=16 (PS128 RAB) in DL. (32) – • • • • Admission limit for non-guaranteed traffic class connections with DL SF = 16. Maximum number of radio links with Spreading Factor sf32Adm: Defines the absolute admission limit for the number of RLs with SF=32 (PS64) in DL. (32) sf4AdmUl: Absolute admission limit for the number of RLs with SF=4 in UL (PS384/HS) (0) sf8AdmUl: Defines the absolute admission limit for the number of RLs with SF=8 in UL. (0) sf16AdmUL: Parameter that defines absolute admission limit for the number of RLs with SF=16 in UL. (32) system configuration • primaryCpichPower: Parameter that controls the power level of the Primary CPICH. • maximumTransmissionPower: Parameter that can be used to limit the total DL power in a cell to a value lower than DL power capability of the RBS. (441, 442, 460…) • maxTxPowerUl: Used in UE functions for cell selection/ re-selection in idle mode and connected mode and also used by UTRAN to control the maximum transmitted power level a UE can use. (for ExternalGsmNetwork =100 and for UtranCell=24) Directed retry • loadSharingDirectedRetryEnabled: An RNC-wide flag for turning on the feature. • directedRetryTarget: UA cell specific parameter that specifies the Directed Retry target in terms of a cell reference to an external GSM cell. • loadSharingGSMThreshold: A cell specific parameter that specifies the load sharing threshold below which Directed Retry to GSM is suppressed. • loadSharingGSMFraction: A cell specific parameter that specifies the fraction of qualified speech calls to be diverted to GSM. handover • • • • • • • • • maxActiveSet: Maximum number of cells allowed in the Active Set. IndividualOffset: Offset value which can be assigned to each cell. It is added to the measurement quantity before the UE evaluates whether or not an event has occurred. It can either be positive or negative value. measQuantity1: Defines the measurement quantity for intra-frequency reporting evaluation. Default is Ec/No. hsQualityEstimate: Indicates whether Ec/No or RSCP should be used for indicating "best cell" for HS-DSCH Cell Change. Default is RSCP. reportingRange1a: Relative threshold referred to the CPICH of the best cell in the Active Set used as evaluation criteria for event 1a (a primary CPICH enters the reporting range). reportingRange1b: Relative threshold referred to CPICH of the best cell in the Active Set used as evaluation criteria for event 1b (a primary CPICH leaves the reporting range). reportingInterval1a: Time between periodic reports at event-triggered periodic reporting for event 1a timeToTrigger1a: If event 1a condition is fulfilled during at least a time greater than or equal to timeToTrigger1a milliseconds, then event 1a occurs. timeToTrigger2dEcno: If event 2d condition is fulfilled during at least a time greater than or equal to timeToTrigger2dEcno milliseconds, then event 2d occurs Hasdpa/eul • • • • • • • numHsPdschCodes: Parameter that defines the number of codes allocated in a call only for HS-PDSCH (SF 16). maxNumHsPdschCodes: Defines the maximum number of HS-PDSCH codes that may be allocated in a cell. hsdpaUsersAdm: Cell parameter that defines the admission limit for the number of users assigned to the HS-DSCH. Applicable to admission requests related to RAB setup of an HSDPA service. maxNumHsdpaUsers: Limits the maximum allowed number of simultaneous HSDPA users per cell that can be served. eulServingCellUsersAdm: Defines the admission limit for the number of EUL users having the cell as serving cell. eulNonServingCellUsersAdm: Cell parameter that defines the admission limit foe the number of EUL users having the cell as non-serving cell. hsdschInactivityTimer: Time during which throughput has to be low in order to trigger a down-switch (dedicated to common state) for a UE in state DCH/HS or in state EUL/HS. Idle mode • • • • • • • • • • • • • • • qQualMin: Minimum required quality level in the cell measured in the UE. qRxLevMin: Parameter that indicates the min. required signal strength in the cell qualMeasQuantity: Used for decision as to whether the 3G ranking for cell selection and reselection is based on Ec/No or RSCP. Default is Ec/No. qHyst1: Hysteresis values used for serving cell, when ranking is based on CPICH RSCP qHyst2: Hysteresis values used for serving cell, when ranking is based on CPICH Ec/No qOffset1sn: Signal strength offset b/w source and target cell for cell ranking based on CPICH RSCP. qOffset2sn: Signal offset between serving cell and neighbor cell, based on CPICH Ec/No. sIntraSearch: Decision on when intra-freq. measurements should be performed. Following criteria is used: sIntraSearch ≥ qQualmeas - qQualMin (where qQualmeas is the value measured by UE ) sInterSearch: Parameter is used to make decision to start inter-freq. measurements. sInterSearch ≥ qQualmeas - qQualMin (where qQualmeas is the value measured by UE ) sRatSearch: Decision on when GSM measurement should be performed in relation to qQualMin. sRatSearch ≥ qQualMeas – qQualMin (where qQualmeas is the value measured by UE ) sHcsRatSearch: Decision on when GSM measurement should be performed in relation to qRxLevMin. sHcsRatSearch ≥ qRxLevMeas – qRxLevMin (where qRxLevMeas is the value measured by UE) IRAT • • • • • usedFreqThresh2dRscp: Threshold for event 2d (the estimated quality of the currently used WCDMA RAN frequency is below a certain threshold) based on RSCP measurements. usedFreqThresh2dEcno: Threshold for event 2d (the estimated quality of the currently used WCDMA RAN frequency is below a certain threshold) based on Ec/No measurements.. gsmThresh3a: Threshold for event 3a (the estimated quality of the currently used WCDMA RAN frequency is below a certain threshold and the estimated quality of the GSM system is above a certain threshold) for GSM. gsmPropRepeatInterval: Minimum time interval between proposals of the same GSM cell for handover based on the same measurement report. gsmAmountPropRepeat: Maximum number of repeated proposals (not including the first proposal) of GSM cells for handover based on the same measurement report. RRC Connection Setup Counters • • • • • • • • • pmTotNoRrcConnectReq: Number of RRC Connection Requests pmTotNoRrcConnectReqSuccess: Number of successful RRC Connection Requests pmNoRrcReqDeniedAdm: Number of RRC requests denied by admission control pmTotNoRrcConnectReqCs: Number of Conversat. and Emerg. call RRC Connection Requests pmTotNoRrcConnectReqCsSucc: Number of successful Conversat. and Emerg. Call RRC requests pmNoRrcCsReqDeniedAdm: Number of CS calls denied by Admission Control pmTotNoRrcConnectReqPs Number of Int. and Background RRC Connection Requests pmTotNoRrcConnectReqPsSucc Number of Successful Int. and Background RRC Conn attempts pmNoRrcPsReqDeniedAdm Number of PS calls denied by admission control RAB Establishment • • • • • • • pmNoRabEstablishAttemptSpeech: Number of RAB establishment attempts for speech pmNoRabEstablishSuccessSpeech: Number of successful RAB establishments for speech pmNoRabEstablishAttemptPacketInteractive: Number of successful RAB establishments for PS Int. RAB pmNoRabEstablishAttemptPacketInteractiveHs: No. of RAB estab. att. for PS Int. RAB mapped on HS-DSCH pmNoRabEstablishSuccessPacketInteractiveHs: No. of successful RAB estab for PS Int. RAB mapped on HSDSCH pmNoRabEstablishAttemptPacketInteractiveEul: No. of RAB est. att. for PS Int. RAB mapped on EDCH/HSDSCH. pmNoRabEstAttemptPsIntNonHs: No. of RAB establishment att. for PS Int. RAB in a non-HS (DCH or FACH) config. pmNoRabEstSuccessPsIntNonHs: No. of succ. RAB establish. for PS Int. RAB in a non-HS (DCH or FACH) config. Retainability Counters • • • • • • • • pmNoNormalRabReleaseSpeech: Number of successful normal RAB releases (Speech) pmNoSystemRabReleaseSpeech: Number of successful system RAB releases (Speech drops) pmNoNormalRabReleasePacket: Number of successful normal RAB releases (PS) pmNoSystemRabReleasePacket: Number of successful system RAB releases (PS drops) pmNoNormalRbReleaseHs: Number of successful normal releases of packet RABs mapped on HS-DSCH pmNoSystemRbReleaseHs: Number of successful system releases of packet RABs mapped on HS-DSCH pmNoNormalRbReleaseEul: Number of normal RAB releases of PS Int. RAB mapped on E-DCH/HS-DSCH pmNoSystemRbReleaseEul: No. of system RAB releases of PS Int. RAB mapped on E-DCH/HS-DSCH IRATs • • • • • • • pmNoDirRetryAtt: Number of attempted outgoing inter RAT HO due to capacity pmNoDirRetrySuccess: Number of successful outgoing IRAT HO due to capacity pmNoAttOutIratHoSpeech: No. of attempted outgoing IRAT HO for speech pmNoSuccessOutIratHoSpeech: No. of successful outgoing IRAT HO for speech pmNoFailOutIratHoSpeechGsmFailure: No. of failed outgoing IRATs due to GSM allocation failure pmNoFailOutIratHoSpeechReturnOldChPhyChFail: No. of failed outgoing IRATs due to physical channel failure, where UE returns to present active set pmNoFailOutIratHoSpeechReturnOldChNotPhyChFail: No. of failed outgoing IRAT HOs due to reasons other than physical channel failure, where UE returns to present active set. Handover • pmNoTimesRlAddToActSet: Number of times RL is added/ replaced to an active set • pmNoTimesCellFailAddToActSet: Number of times a cell fails to be added to an active set • pmNoRlDeniedAdm: Number of RL setups or RL addition requests denied by admission Availability • • • • • • pmCellDowntimeMan: Time that cell has been unavailable because of admin state being manually locked. pmCellDowntimeAuto: Time that cell has been unavailable due to a fault PmHsDowntimeMan: Time that HSDSCH in a cell is unavlbe. due to operation settings pmHsDowntimeAuto: Time that HSDSCH in a cell is unavailable due to system taking cell as down pmEulDowntimeMan: Time that Eul srvc in a cell is unavailable due to operator settings pmEulDowntimeAuto: Time that Eul service is unavailable bcs the system has considered the cell as down Transport (Iub) • • • • • • pmSuccInConnsRemoteQosClassA: No. of successful establishments of incoming connections on this AAL2 Access Point (AP). The counter increments in terminating node. pmSuccOutConnsRemoteQosClassA: No. of successful establishments of outgoing connections on this AAL2 Access Point. The counter increments in terminating node. pmUnSuccInConnsLocalQosClassA: Number of unsuccessful attempts to allocate AAL2 path resources during establishment of incoming connections pmUnSuccInConnsRemoteQosClassA: No. of unsuccessful estab. of incoming connect. on this AAL2 AP caused by the reject in remote node. Increments in a Terminating node pmUnSuccOutConnsLocalQosClassA: Number of unsuccessful attempts to allocate AAL2 resources during establishment of outgoing connections on this Access Point pmUnSuccOutConnsRemoteQosClassA: Number of unsuccessful establishments of outgoing connections on this AAL2 Access Point (AP). Admission Control • • • • • • • • • pmNoFailedRabEstAttemptLackDlHw: Number of failed RAB establishments attempts due lack of DL hardware resources pmNoFailedRabEstAttemptLackUlHw: Number of failed RAB establishments attempts due to lack of UL hardware resources pmNoFailedRabEstAttemptLackDlAse: Number of a failed RAB establishments attempts due to lack of DL ASE pmNoFailedRabEstAttemptLackUlAse: Number of failed RAB establishments attempts due to lack of UL ASE pmNoFailedRabEstAttemptExceedConnLimit: No. of failed PS RAB estab att due to exceeding SF (8,16,32) connection limit pmNoFailedRabEstAttemptLackDlChnlCode: No. of failed RAB estab attempts due to lack of DL channelization codes pmNoFailedRabEstAttemptLackDlPwr: Number of failed RAB establishment attempts due to lack of DL power. pmNoFailedAfterAdm: No. of RRC or RAB establishments failed after being admitted by admission control. pmNoReqDeniedAdm: No. of RAB establishment and RRC requests rejected by admission control Drop Reasons • • • • pmNoSysRelSpeechNeighbr: No. of sys disconnects of a speech call due to missing (non-valid) neighbor relation pmNoSysRelSpeechSoHo: No. of system disconnects of a speech call due to soft handover (valid/non-valid) pmNoOfTermSpeechCong: Number of Speech Radio Connections served by RNC terminated due to congestion pmNoSysRelSpeechUlSynch: Number of system disconnects of a speech call due to lost UL synch Transmission • pmEs: Transmission Errored Seconds • pmSes: Transmission Severely Errored Sec. • pmUas: Transmission Unavailable Seconds Ericsson Important Optimization Parameters (1) System Configuration primaryCpichPower: Parameter that controls the power level of the Primary CPICH. maximumTransmissionPower: Parameter that can be used to limit the total DL power in a cell to a value lower than DL power capability of the RBS. maxTxPowerUl: Used in UE functions for cell selection/ re-selection in idle mode and connected mode and also used by UTRAN to control the maximum transmitted power level a UE can use. Capacity Management compModeAdm: Absolute admission limit for the number of radio links in compressed mode in a cell. dlCodeAdm: Parameter that defines in percentage the absolute admission limit for DL code usage pwrAdm: Parameter that defines in percentage the absolute admission limit for DL power utilization. sf8Adm: Defines the absolute admission limit for the number of RLs with SF=8 (PS384) in DL. sf16Adm: Defines the absolute admission limit for the number of RLs with SF=16 (PS128 RAB) in DL. sf32Adm: Defines the absolute admission limit for the number of RLs with SF=32 (PS64) in DL. sf4AdmUl: Absolute admission limit for the number of RLs with SF=4 in UL (PS384/HS) sf8AdmUl: Defines the absolute admission limit for the number of RLs with SF=8 in UL. sf16AdmUL: Parameter that defines absolute admission limit for the number of RLs with SF=16 in UL. Directed Retry loadSharingDirectedRetryEnabled: An RNC-wide flag for turning on the feature. directedRetryTarget: UA cell specific parameter that specifies the Directed Retry target in terms of a cell reference to an external GSM cell. loadSharingGSMThreshold: A cell specific parameter that specifies the load sharing threshold below which Directed Retry to GSM is suppressed. loadSharingGSMFraction: A cell specific parameter that specifies the fraction of qualified speech calls to be diverted to GSM. Handover maxActiveSet: Maximum number of cells allowed in the Active Set. IndividualOffset: Offset value which can be assigned to each cell. It is added to the measurement quantity before the UE evaluates whether or not an event has occurred. It can either be positive or negative value. measQuantity1: Defines the measurement quantity for intra-frequency reporting evaluation. Default is EcNo. hsQualityEstimate: Indicates whether Ec/No or RSCP should be used for indicating "best cell" for HS-DSCH Cell Change. Default is RSCP. reportingRange1a: Relative threshold referred to the CPICH of the best cell in the Active Set used as evaluation criteria for event 1a (a primary CPICH enters the reporting range). reportingRange1b: Relative threshold referred to CPICH of the best cell in the Active Set used as evaluation criteria for event 1b (a primary CPICH leaves the reporting range). reportingInterval1a: Time between periodic reports at event-triggered periodic reporting for event 1a timeToTrigger1a: If event 1a condition is fulfilled during at least a time greater than or equal to timeToTrigger1a milliseconds, then event 1a occurs. timeToTrigger2dEcno: If event 2d condition is fulfilled during at least a time greater than or equal to timeToTrigger2dEcno milliseconds, then event 2d occurs Ericsson Important Optimization Parameters (2) HSDPA/EUL numHsPdschCodes: Parameter that defines the number of codes allocated in a call only for HS-PDSCH (SF 16). maxNumHsPdschCodes: Defines the maximum number of HS-PDSCH codes that may be allocated in a cell. hsdpaUsersAdm: Cell parameter that defines the admission limit for the number of users assigned to the HS-DSCH. Applicable to admission requests related to RAB setup of an HSDPA service. maxNumHsdpaUsers: Limits the maximum allowed number of simultaneous HSDPA users per cell that can be served. eulServingCellUsersAdm: Defines the admission limit for the number of EUL users having the cell as serving cell. eulNonServingCellUsersAdm: Cell parameter that defines the admission limit foe the number of EUL users having the cell as non-serving cell. hsdschInactivityTimer: Time during which throughput has to be low in order to trigger a down-switch (dedicated to common state) for a UE in state DCH/HS or in state EUL/HS. IRAT usedFreqThresh2dRscp: Threshold for event 2d (the estimated quality of the currently used WCDMA RAN frequency is below a certain threshold) based on RSCP measurements. usedFreqThresh2dEcno: Threshold for event 2d (the estimated quality of the currently used WCDMA RAN frequency is below a certain threshold) based on EcNo measurements.. gsmThresh3a: Threshold for event 3a (the estimated quality of the currently used WCDMA RAN frequency is below a certain threshold and the estimated quality of the GSM system is above a certain threshold) for GSM. gsmPropRepeatInterval: Minimum time interval between proposals of the same GSM cell for handover based on the same measurement report. gsmAmountPropRepeat: Maximum number of repeated proposals (not including the first proposal) of GSM cells for handover based on the same measurement report. Idle Mode (Selection/ Reselection) qQualMin: Minimum required quality level in the cell measured in the UE. qRxLevMin: Parameter that indicates the min. required signal strength in the cell qualMeasQuantity: Used for decision as to whether the 3G ranking for cell selection and reselection is based on EcNo or RSCP. Default is EcNo. qHyst1: Hysteresis values used for serving cell, when ranking is based on CPICH RSCP qHyst2: Hysteresis values used for serving cell, when ranking is based on CPICH EcNo qOffset1sn: Signal strength offset b/w source and target cell for cell ranking based on CPICH RSCP. qOffset2sn: Signal offset between serving cell and neighbor cell, based on CPICH EcNo. sIntraSearch: Decision on when intra-freq. measurements should be performed. Following criteria is used: sIntraSearch ≥ qQualmeas - qQualMin (where qQualmeas is the value measured by UE ) sInterSearch: Parameter is used to make decision to start inter-freq. measurements. sInterSearch ≥ qQualmeas - qQualMin (where qQualmeas is the value measured by UE ) sRatSearch: Decision on when GSM measurement should be performed in relation to qQualMin. sRatSearch ≥ qQualMeas – qQualMin (where qQualmeas is the value measured by UE ) sHcsRatSearch: Decision on when GSM measurement should be performed in relation to qRxLevMin. sHcsRatSearch ≥ qRxLevMeas – qRxLevMin (where qRxLevMeas is the value measured by UE) Comparison of parameters between some RNCs • • • • >amos -m RNCE1, RNCE2, RNCE3 >lt rncfunction >get rncfunction (to find the proxy) >diff 125285 125284 Restart Ranks, cont Data in own memory segment Domain Preserved Cleared 4 Conditional Cleared Cleared 1, 2, 3, 4 Yes Cleared Cleared 1, 2 Rank T&E logs HW test HW reset SW reload Hot Preserved No No Conditional Warm Preserved No No Yes on MP/BP Not necessarily on FPGA/DSP/etc. Data in CLI container Refresh Preserved No Cold Cleared Limited Yes Yes Cleared Cleared 1, 2, 3 ColdWTest Cleared Yes Yes Yes Cleared Cleared 1, 2, 3 Restart commands from MO interface RNCSM01> acc 0 manualrestart Call Action manualrestart on following MOs ? =============================================================================== 0 ManagedElement=1 =============================================================================== Are you Sure [y/n] ? y =============================================================================== Proxy MO Action Nr of Params =============================================================================== 0 ManagedElement=1 manualRestart 3 Parameter 1 of 3, restartRank (enumRef-RestartRank): Enter one of the following integers: 0:RESTART_WARM, 1:RESTART_REFRESH, 2:RESTART_COLD, 3:RESTART_COLDWTEST: 0 Parameter 2 of 3, restartReason (enumRef-RestartReason): Enter one of the following integers: 0:PLANNED_RECONFIGURATION, 1:UNPLANNED_NODE_EXTERNAL_PROBLEMS, 2:UNPLANNED_NODE_UPGRADE_PROBLEMS, 3:UNPLANNED_O_AND_M_ISSUE, 4:UNPLANNED_CYCLIC_RECOVERY, 5:UNPLANNED_LOCKED_RESOURCES, 6:UNPLANNED_COLD_WITH_HW_TEST, 7:UNPLANNED_CALL_PROCESSING_DEGRADATION, 8:UNPLANNED_LOW_COVERAGE: 0 Parameter 3 of 3, restartInfo (string): eanzmagn >>> Return value = null =============================================================================== Total: 1 MOs attempted, 1 MOs actioned Restart commands from MO interface Board restart using the MO LDN RNCSM01> acc ms,slot=9,pluginunit=1$ manualrestart ...<cut>... Board restart using a board group RNCSM01> acc mod1 manualrestart ...<cut>... Checking Restart Information RNCSM01> lgvsm RNCSM01> lgd !Node restart times! RNCSM01> lhsh 001400 llog –l!board restarts logs! RNCSM01> cabr !all board! Parameter Audit RNCSM01> h diff ******************************************************* diff/ldiff ******************************************************* .... 2) Syntax 2: diff/ldiff <moGroup>|<moFilter>|<proxy>|<modumpFile>|<modumpDir> [<baselineFile>|<modumpFile2>|default] [<outputDir>] To compare an MO dump with a parameter baseline file or with another MO dump. etc..... From the unix prompt, do: If one node only: moshell <ipaddress> ‘lt all ; diff . ‘ If many nodes: mobatch <sitefile> ‘lt all ; diff . ‘ For using another baseline file: moshell <ipaddress> ‘lt all ; diff . mybaseline.txt‘ If many nodes: mobatch <sitefile> ‘lt all ; diff . mybaseline.txt‘ Traffic per Cell See all major KPIs per Site and Per RNC Active Emergency Lisence acc Licensing=1 setEmergencyState (WNCS) WCDMA Neighboring Cell Support Table of Contents • • • • Overview Data Collection Reports & Analysis Export Reports Overview • WNCS is an optional feature and it is part of the Radio Network Optimization (RNO) in OSS-RC. • WNCS feature provides an easy and efficient way to keep the neighbor relations optimized by – Identifying missing neighboring cells that should be defined as neighbors. – Identifying existing defined neighbor relations that can be removed(Optimizers generally does not use this method) • WNCS feature can only support neighbor optimization between cells using the same frequency. • WNCS feature uses GPEH events to identify missing neighbor relations and counters to measure the existing defined neighbor relation usage. Data Collection • WNCS is part of the RNO and can be access in OSS-RC as shown. Data Collection • In RNO -> Select File -> New Recording -> NCS… 1 1. Name this recording 2. Select Both GPEH and Counters 3. Define recording period Start time should be at least 5 mins before the next ROP. 4. Select cells to include in this recording. 5. Add optional comment to this recording. 6. Select Save and Schedule to schedule this recording. 2 3 5 4 6 Data Collection – Additional Info • Data to Measure • There are three choices: – Both GPEH events and Counters – Only GPEH events – Only Counters • If "Only GPEH events" is selected, then no data for monitored neighbors will be available in the reports. (defined neighbor usage % will be missing) • If "Only Counters" is selected, then no data for missing and unmonitored neighbors will be available in the reports. • Recommend to select “Both GPEH events and Counters”. Reports & Analysis • NCS Overview Report presents the results of a recording in a table where the reported scrambling codes are summarized for each cell. • These results are used to determine which cells have neighbor relations that can be improved. • From this report a cell can be selected to be further analyzed in the cell report. Reports & Analysis • The overview report can be used to quickly find the cells that have the most problems with the neighbor definitions, especially many missing neighbor detections and drops. Sort in descending order to identify cells with high number of events from missing neighbor. This indicates that the cell has undefined neighbor cells that should be defined as neighbors. Consider also the number of drops when determining the order of which the cells should be attended to. Select the cell with most severe problems and open the NCS Cell Report. Reports & Analysis NCS Cell Report presents detailed information about each cell. Double-click on the cell in the Overview Report to view the Cell Report. NCS Cell Report Defined Neighbors Undefined Neighbors Find missing neighbor relations that can be added Monitored Neighbors Find neighbor relations that can be removed Unmonitored Neighbors Review the priority status of cells that appeared as unmonitored neighbor in the current neighbor list Reports & Analysis – Delete Neighbor Use the Relative Usage column to find defined neighbors that are never used and can be removed. Before removing a neighbor definition it should be considered if the statistics is enough and covers different hours and different traffic patterns during the day, and that the cell was operational during the recording. Neighbor relations with significant amount of usage combined with a cell distance much larger than the other neighbors could be the coverage of the target cell overshooting other cells. A monitored neighbor list showing more than 25 neighbor relations, all with significant amount of usage, is an indication the source cell being overshooting surrounding cells. Note that the relative usage consider only speech traffic. To remove neighbor : Select the neighbor to be removed and follow the menu selection as shown. This will be saved in WNCS Change Order. Reports & Analysis Defined Neighbor Column Header Descriptions • Cell Name – The cell name of the monitored defined neighbor. • Cell User Label – The cell user label of the monitored defined neighbor. • Scrambling Code – The scrambling code for the monitored defined neighbor. • No. of Attempts – The number of RL addition attempts for this monitored defined neighbor. • Success (%) – The percentage of the RL addition attempts that was successful. • Failures (%) – The percentage of the RL addition attempts that failed. • Relative Usage (%) – The number of attempts for this neighbor compared to number of attempts for all neighbors for the cell that the report shows. Reports & Analysis Defined Neighbor Column Header Descriptions • Selection Priority – In order to reduce the number of dropped calls the neighbor cell relations have to be prioritized to avoid unwanted truncation of best-ranked neighbors (which could happen if the number of defined neighbors are more than approximately 20). The selection priority property of the neighbor cell relation enables that prioritization, it is used to rank neighbor cell relations for inclusion in the monitored set. • Operational State – The operational state of the neighbor during the recording periods. The operational state can be active, partly active or inactive. Active means that the cell has been active in all recording periods. Partly active means that the cell has been both active and inactive during the recording and switched state between periods. Inactive means that the cell has been inactive in all recording periods. If the neighbor cell belongs to another OSS the column is empty. • Distance (km) – Distance between the antenna of the measuring cell and the antenna of the defined neighbor in kilometers. The altitude of the antennas are not considered, only longitude and latitude are used for the distance calculation. To change priority of a neighbor : Select the target neighbor and follow the menu selection as shown. A Set Selection Priority prompt will appear. Enter the new priority number and select OK. This will be saved in WNCS Change Order. Reports & Analysis Unmonitored Neighbor Column Header Descriptions • Cell Name – The cell name of the unmonitored defined neighbor. • Cell User Label – The cell user label of the unmonitored defined neighbor. • No. of Detections – The number of detections for this unmonitored defined neighbor. • Selection Priority – In order to reduce the number of dropped calls the neighbor cell relations have to be prioritized to avoid unwanted truncation of best-ranked neighbors (which could happen if the number of defined neighbors are more than approximately 20). The selection priority property of the neighbor cell relation enables that prioritization, it is used to rank neighbor cell relations for inclusion in the monitored set. • Operational State – The operational state of the neighbor during the recording periods. The operational state can be active, partly active or inactive. Active means that the cell has been active in all recording periods. Partly active means that the cell has been both active and inactive during the recording and switched state between periods. Inactive means that the cell has been inactive in all recording periods. If the neighbor cell belongs to another OSS the column is empty. • Distance (km) – Distance between the antenna of the measuring cell and the antenna of the defined neighbor in kilometers. The altitude of the antennas are not considered, only longitude and latitude are used for the distance calculation. Reports & Analysis – Add Neighbor 1. Sort in descending order to identify the highest number of missing events from missing neighbor candidate. 2. Taken into considering also the number of drops. 3. Check the neighbor candidate in the NCS Probable Cell Name Diagnostics Report to evaluate the risk of mixed up cell names. Also use the distance information to determine the most probable cell. (It is therefore important to have the correct latitude and longitude coordinates configured in the RBS and must be configured for all cells) 4. Add neighbor candidate after its identity is confirmed and should be added as neighbor. To add a neighbor : Select the neighbor to add and follow the menu selection as shown. A Set Selection Priority prompt will appear. Assign a priority number for the new neighbor and select OK. This will be saved in WNCS Change Order. Reports & Analysis Undefined Neighbor Column Header Descriptions • Probable Cell Name – The probable cell name of the missing neighbor. • Scrambling Code – The scrambling code for the missing neighbor. • No. of Possible RL Add. Att. – The number of possible RL addition attempts for this missing neighbor. • No. of Missing Events – The number of missing events for this missing neighbor. • No. of Drops – The number of drops. • Time in Active Set (min) – The time (in minutes) that this missing neighbors could have been in the active set. • Average RSCP (dBm) – Average Received Signal Code Power (RSCP) for the cell that triggered the measurement report. • Average Ec/No (dB) – Average received energy per chip divided by the power density of the band (noise) for the cell that triggered the measurement report. Export Reports • Another method is to export the results and analyze the data using Excel instead of doing it in OSS. • Select the recording you wanted to analyze. Select File -> Export -> Tab Separated Files • Exported file will be saved in this location, /var/opt/ericsson/wncs/data/export/ Export Reports Analyze the report in Excel. (MRR-W) Measurement Result Recording for WCDMA Overview • • MRR-W (Measurement Result Recording for WCDMA) is an useful feature to evaluate and monitor network performance and quality, especially in network tuning and optimization project activities. MRR-W collects statistics from UE, RBS, and RNC, it’s performed for different services and measurement quantities. - measurements period - selected cells - combination of services and measurement quantities (RNC) - spreading factor chosen (RBS) UE & RNC Meas MRR-W activation at RNO: DL BLER UL BLER stored at RNC xml files Ue Tx Power DL CPICH EcNo DL CPICH RSCP RBS DL Tx Code Power stored at RBS xml files Overview • The following services and RAB are supported: – Speech12200 Speech Narrow Band 12.2. – AMR4750 Speech AMR NB 4.75. – AMR5900 Speech AMR NB 5.9. – AMR7950 Speech AMR NB 7.95. – AMRWB Speech AMR Wide Band. – Video Includes RAB configurations with CS64, also together with low rate PS interactive connections. – PSINTDCHDCH Includes PS Interactive RAB configurations with supported UL and DL rates on DCH. – PSINTDCHHS Includes PS interactive RAB configurations with supported rates on DCH in UL and HSDPA in DL. – PSINTEULHS Includes PS Interactive RAB configurations on EUL/HS. – PSSTRDCHHS Includes PS Streaming RAB configurations with supported rates on DCH in UL and HSDPA in DL. – PSSTRDCHDCH Includes PS Streaming RAB configurations with supported rates on DCH. – Speech12200_ALL Includes multi-RAB configurations with Speech NB 12.2 together with Interactive and Streaming RABs on both DCH and HS. Note that BLER measurements are performed for the speech part. – AMRWB_ALL Includes multi-RAB configurations with Speech WB together with Interactive and Streaming RABs on both DCH and HS. Note that BLER measurements are performed for the speech part. – CSStreaming CS Streaming 57.6 on DCH. – PSSTRDCHHS_ALL Includes PS Streaming RAB configurations with supported rates on DCH in UL and HSDPA in DL, together with PS interactive RABs on DCH and HS. – AMRNBMM Speech AMR Narrow Band Multimode. – AMRNBMM_ALL Includes multiRAB configurations with Speech AMR Narrow Band Multimode together with PS interactive RABs on DCH and HS. Data Collection • MRR-W is part of the RNO and can be access in OSS-RC as shown. Data Collection Create recording name & recording periods Select recording cells Save & Schedule when completed Select service & the quantity to be included in the recording. (see next slide for details) Data Collection 1. Select “P7MD or earlier” for RAN P7.0.3 2. Allows up to 6 Service and measurement quantity per cell. For P7FP or later, the allowance is maximum of 12. 3. Set the sampling periods and the UE fraction. (details in next slide) 4. Select DL Tx Code Power per SF to be included in the recording (if required). • • • • The sample periods for the periodic measurements can be set between 2 and 64 seconds, separately for speech, video, streaming and interactive, which then also applies to the corresponding multi-RAB combinations. For the UE measurements this is the interval with which the UE is ordered to send periodic measurement reports. The UE fraction can be set to the values FULL, 1/2, 1/3, 1/4 and 1/5, which has the effect of including this fraction of the users in the recording. The UE fraction can be used to reduce the load and scope of the recording, and is primarily intended to be used when high sample rates are required. Reporting • Through RNO main window in OSS. Double-click on selected MRR-W report to access Overview Report. Reporting • MRR-W Overview Report contains a summary of the recording results. 10.34% of the samples for cell UT0616YA1 has Ec/No worst than -12dB 2.44% of the samples for cell UT1033XB2 has RSCP< -100dBm Reporting • The MRR-W cell histogram displays the actual detailed measurement results for each cell, in the form of pdf distributions. • These histograms can be used for detailed analysis of the quality and radio environment for each cell. Results obtained with MRR-W Statistical radio measurements per cell. • Cells properly tuned have: – – – – Most UEs with low TX Power. Most UEs have good Ec/No. Most UEs have good RSCP. BLER is according to target for service. Results obtained with MRR-W Statistical radio measurements per cell - TxPower. “Uplink Coverage” of a particular cell. As it can be obtained per service, one can see if a particular service: – runs out of power – has a coverage that has shrunk. “Downlink Coverage” of a particular cell. It can be obtained per Spreading Factor, which is related to services. One can see if a particular SF (or even service): – runs out of power – has a coverage that has shrunk. Results obtained with MRR-W Statistical radio measurements per cell - BLER. Downlink quality of a particular cell Uplink quality of a particular cell It can be obtained per services, separately: – Speech needs a very low BLER Results obtained with MRR-W Statistical radio measurements per cell - CPICH. CPICH Ec/No (“interference in the cell”) CPICH RSCP (“signal strength, pathloss”) CPICH to identify coverage problems: CPICH RSCP Very weak: why? - Lack of coverage. - Lots of indoor traffic. - Handover problem. IRAT/IF HO problem. - Cell overshooting. FFAx-W Find Faulty Antenna Expert for WCDMA Find Faulty Antenna Expert for WCDMA • This presentation contains a summary about OSS-RC feature Find Faulty Antenna Expert for WCDMA, and instructions how to start FFAX-W and a few problem identification examples. Find Faulty Antenna Expert for WCDMA Summary • FFAX-W can be used for remote antenna problem identification. With FFAX-W, it is possible to measure the performance of the antenna system at every sector. • The data is collected from the antenna receiver branches in RBS and is processed in OSS-RC, thereby enabling the system to identify poorly performing antenna installations as well as providing an indication of the type of fault. Find Faulty Antenna Expert for WCDMA Benefits Antenna systems that perform below their optimum are detected Data is collected with an absolute minimum of effort as well as very quickly for an entire network avoiding costly drive tests or other type of on site investigations Cost efficient way of finding faulty antenna installations Reduction of the time needed between problem detection and correction. The FFAX-W enables operators to send personnel on site with knowledge of what needs to de fixed. Antenna systems that perform below their optimum are detected The system can benefit fully from the functionalities receiver diversity, transmitter diversity and MIMO Data is collected with an absolute minimum of effort as well as very quickly for an entire network avoiding costly drive tests or other type of on site investigations Reduction of the time needed between problem detection and correction (e.g. same day depending on site location). The feature enables operators to send personnel on site with knowledge of what needs to be fixed More efficient acceptance procedure for operators if third party resources are used for e.g. installation or site maintenance Areas which suffer from e.g. storms or hurricanes can be monitored proactively Find Faulty Antenna Expert for WCDMA Short theory how FFAX-W works • RBS measurements: – Radio Base Station (RBS) measures the difference in SIR per receive branch as pdf counters, pmBranchDeltaSir. • Data is fed to OSS-RC for analysis: – Difference between two diversity branches should be small, but in case the difference is significant or the variation is larger than expected, this is a strong indication that at least one of the antenna branches is not performing optimally. FFAX-W: pmBranchDeltaSir pmBranchDeltaSir The difference in SIR per receive branch per connection (DPCCH) per cell. The purpose with the measurement is to detect faulty feeder installations. Counter type: PDF Counter is reset after measurement interval: Yes Condition: One measurement every 1000 ms. The actual measurement will start on all enabled UBCH device set. Only valid measurement values will be used in the pm-counters. If there is no signal on any branch the difference in SIR is excluded. PDF ranges: [0]: Value : SIR sample in range =< -29.5 dB [1]: Value : SIR sample in range [-29.5 .. -28.5[ dB [2]: Value : SIR sample in range [-28.5 .. -27.5[ dB ... [29]: Value : SIR sample in range [-1.5 .. -0.5[ dB [30]: Value : SIR sample in range [-0.5 .. 0.5[ dB [31]: Value : SIR sample in range [0.5 .. 1.5[ dB ... [58]: Value : SIR sample in range [27.5 .. 28.5[ dB [59]: Value : SIR sample in range [28.5 .. 29.5[ dB [60]: Value : SIR sample in range >= 29.5 dB Undefined value: -1 MaxLength=61 FFAX-W problem identification • FFAX-W can indicate the following states based on SIR measurement: 1. Normal – no failure 2. Losses in RF path 3. Antenna diagram mismatch 4. Swapped Feeder 5. Missing feeder PROCEDURE TO VERIFY FFAX-W OVERVIEW REPORTS IN RNO 2. Losses in RF path Condition: “Average SIR Difference” should be more than 3 dB and “Standard Deviation SIR Difference” should be less than (average-3) + 5 dB 3. Swapped feeder Condition: “Standard Deviation SIR Difference” should be more than 10 dB 4. Missing Feeder Condition: “Average SIR Difference” should be 29.5 or -29.5. 5. Antenna Diagram Mismatch Condition: “Average SIR Difference” should be greater than 3dB and “Standard Deviation SIR Difference” should be greater than or equal to (Average SIR Difference -3)/8. Problem identification SIR difference indicates potential problem SIR diff -29.5 +29.5 SIR diff -29.5 Losses in RF path -29.5 +29.5 * Average SIR difference > 3 dB * Std dev > (average-3)+5 dB -29.5 +29.5 * Average SIR difference = 29.5 or -29.5 Antenna diagram mismatch +29.5 * Average SIR difference > 3 dB * Std dev < (average-3) + 5 dB +29.5 * Std dev > 10 dB * Average SIR difference < 3 dB * Std dev < 10 dB -29.5 Missing feeder Swapped Feeder Normal (no failure) FFAX-W recording 1. Open Radio Network Optimization (RNO) FFAX-W recording 2. In RNO select New Recording and FFAX-W… FFAX-W recording 3. Give a Recording name. 4. Select recording periods and start date. 5. Select how many times recording will be repeated. FFAX-W recording 6. Select Cells or Cell Sets, and press OK. FFAX-W recording 7. Start recording, press Save and Schedule. FFAX-W problem identification When recording is completed in RNO, double click it and FFAX-W Overview Report window will open. problem identification No fault By double clicking Cell Name in Report, FAXX-W Cell Histogram window will open. Average difference < B dB Std deviation < A dB 1.08 < 3 6.15 < 10 problem identification losses in rf path Average difference > B dB Std < ((average-B)/C + D) 13.01 > 3 6.66 < ((13.01 – 3)/3 + 5) problem identification missing feeder * Average SIR difference = 26.28 problem identification antenna diagram mismatch Antenna diagram mismatch: Average difference > B dB Std deviation >= ((average-B)/C + D) 4.06 > 3 6.64 >= ((4.06 – 3)/3 + 5) problem identification SWAPPED feeder Example from Swapped Feeders: Standard deviation > A dB 16.63 > 10 USING Bussiness objects for result analysis CONCLUSIONS • The required number of samples in a cell is minimum 3000, cells with lower number of samples should be taken out of the analysis. • Due to the relatively low traffic, at least four-five hour recording time was needed to obtain adequate data. • It is recommended to make two-three consecutive recordings in order to securely identify a faulty cell. • Periodic evaluation of the performance is needed. Each month, Operator should repeat FFAX measurement. • After natural events FFAX should be scheduled. For example; – – – – Rain Wind Earthquake Sand • • • • • RNC>get site servicearea (to see LAC and CI) RNC>get site routingarea (to see RAC) Site>st nba (NBAP must be enable for getting traffic Site>get sync Site>get .hsdpacap