CPRI测试仪.ppt

CPRI Option for TX300Training REV Cn Network Overviewn CPRI Technology Primern Test Methodologyn TX300 CPRI Configuration and ResultsVeEX CPRI TrainingConfidential&Proprietary Information of VeEX Inc.2AgendaNetwork OverviewConfidential&Proprietary Information of VeEX Inc.3VeEX CPRI TrainingConfidential&Proprietary Information of VeEX Inc.4Traditional RAN ArchitectureTraditional MacrocellCoreBTS/NodeBBTS/NodeBBTS/NodeBBSC/RNCUuBase StationBackhaul:Ethernet or E1/T1 VeEX CPRI TrainingConfidential&Proprietary Information of VeEX Inc.5Base Station co-located with Radio Tower Base Station/Node BTraditional deployment the base station functions are co-located with the radio tower at the base of the antenna or basement of a tall building.Drawbacks of co-location:nRF transceiver and power amplifier needed to drive the radio functions are co-located with the other functions of the base station such as backhaul transport,control and baseband processing.nNeeds to be physically located very close to the antenna because they are driven over very lossy electrical cables.nHigh power dissipation requires that require costly special enclosures with climate control and power redundancynMakes it difficult to install and find a location that can host the enclosure and/or increase lease price due to additional space needed Electrical cableVeEX CPRI TrainingConfidential&Proprietary Information of VeEX Inc.6Distributed Antenna System ModelDASRERERadio Equipment ControllerRadio EquipmentREREC handles:Network Interface transport Radio base station control and managementDigital baseband processingRECBackhaul:Ethernet over Fiber/MicrowaveRE handles:Radio frequency functionsPower amplifierFronthaul:CPRI/OBSAI over Fiber Base Station Hotelin CO or ColocationDAS is not to be confused with micro-cell,pico cells!VeEX CPRI TrainingConfidential&Proprietary Information of VeEX Inc.7Benefits of distributed modelnOne REC(Radio Equipment Controller)can manage many REs(Radio Equipment)nREC can be physically located far from radio towers in a centralized indoor location and temperature controlled environmentnREC to RE optical link allows long distances(up to 10 km)without loss.nSimplified RE function makes it more compact,easier to install and therefore increases the number of possible sites nFurther economy of scale by having one REC manage many towers,and also increases the deployment flexibility to add new cell sites.VeEX CPRI TrainingConfidential&Proprietary Information of VeEX Inc.8The need for CPRI/OBSAInThe communication link between the REC and RE must be able to support:Transport of digital radio data over either optical or electrical media Transport mechanism flexible to support multiple protocols(UMTS,WiMAX,LTE)Support demand for large bandwidth In-band transport of a high-stability network frequency and time references Accurate calibration of the link delay Multi-vendor interoperabilitynCPRI and OBSAI are two competing standardsnCPRI stands for Common Public Radio Interface,this protocol has been developed by Ericsson AB,Huawei Technologies Co.Ltd,NEC Corporation,Alcatel Lucent and Nokia SiemensnOBSAI stands for Open Base Station Architecture Initiative,this protocol has been developed by Hyundai,LGE,Nokia,Samsung and ZTEnCPRI Rates range from 614 Mbps to 9.8 GbpsnOBSAI Rates range from 728 Mbps to 6.8 GbpsnCPRI has higher market penetration rate than OBSAIVeEX CPRI TrainingConfidential&Proprietary Information of VeEX Inc.9CPRI vs OBSAICPRI Technology PrimerConfidential&Proprietary Information of VeEX Inc.10VeEX CPRI TrainingConfidential&Proprietary Information of VeEX Inc.11CPRI OverviewnCPRI stands for Common Public Radio Interface,this protocol has been developed by Ericsson AB,Huawei Technologies Co.Ltd,NEC Corporation,Alcatel Lucent and Nokia SiemensnIt is an industry cooperation aimed at defining a publicly available specification for the key internal interface of radio base stations between the Radio Equipment Control(REC)and the Radio Equipment(RE)nThe standard is public and can be downloaded from http:/www.cpri.info/nThe current version is v4.2(2010-09-29)VeEX CPRI TrainingConfidential&Proprietary Information of VeEX Inc.12CPRI Interface SpecificationsnCPRI specification defines only Layer 1 and Layer 2nSpecification written with the goal to be generic enough to support scalable rates,physical access medium type and air interface technologiesVeEX CPRI TrainingConfidential&Proprietary Information of VeEX Inc.13CPRI Protocol StackElectrical PHYOptical PHYLine coding:8b/10bFraming&Time Division MuxCPRI Layer 1Physical LayerData Link LayerUser DataControl&ManagementSYNCCPRI Layer 2VeEX CPRI TrainingConfidential&Proprietary Information of VeEX Inc.14Physical LayerThe following Line bit rates are defined in the standard:CPRI line bit rate option 1:614.4 Mbit/s CPRI line bit rate option 2:1228.8 Mbit/s(2 x 614.4 Mbit/s)CPRI line bit rate option 3:2457.6 Mbit/s(4 x 614.4 Mbit/s)CPRI line bit rate option 4:3072.0 Mbit/s(5 x 614.4 Mbit/s)CPRI line bit rate option 5:4915.2 Mbit/s(8 x 614.4 Mbit/s)CPRI line bit rate option 6:6144.0 Mbit/s(10 x 614.4 Mbit/s)CPRI line bit rate option 7:9830.4 Mbit/s(16 x 614.4 Mbit/s)Rates chosen to be integer multiples of UMTS chip rate at 3.84 MVeEX CPRI TrainingConfidential&Proprietary Information of VeEX Inc.15Physical LayerLine coding:8B/10B line coding shall be used for serial transmission according to IEEE 802.3-2005,clause 36.(Same encoding as used for Gigabit Ethernet and Fibre Channel)Bit Error correction/detection:The physical layer is designed in such a way that a very low bit error ratio can be achieved without expensive forward error correction schemes.Therefore,no general bit error correction is applied at layer 1.The RE and the REC shall support detection of 8b/10b code violations.Link failures shall be detected by means of 8b/10b code violations.VeEX CPRI TrainingConfidential&Proprietary Information of VeEX Inc.168B/10B What is it and why is it used?8b/10b is the line code used for Gigabit Ethernet and Fibre Channel.It maps 8 bits of data into a 10 bits symbol,each 8 bits can map into 2 possible 10 bit symbols.The symbols are chosen so that there is a limit of 5 consecutive equal bits and the difference of the count of 0s and 1s is no more than 2.The goal is to achieve DC balance by having a running disparity of 1s and 0s and to provide enough state changes to allow clock recovery.Clock recovery is particularly important because in the CPRI implementation,the RE must recover timing from the 8B/10Bencoded line rate and regenerate the original reference frequency to the required UMTS accuracy.In addition the 8b/10b has several error detection mechanisms:Validation of correct codes(only 268 of the possible 1024 10-bit codes are used)Validation of correct running disparity.Validation that running number of 1s or 0s does not exceed 5.Test MethodologyConfidential&Proprietary Information of VeEX Inc.17QOS Requirements:nBit Error Ratio:nThe interface shall provide U-plane and C&M plane data transmission(on layer 1)with a maximum bit error ratio of 10-12nMaximum Delay:n In order to support efficient implementation of UTRA-FDD inner loop power control3,the absolute round trip time for U-plane data(IQ data)on the interface,excluding the round trip group delay on the transmission medium(i.e.excluding the cable length),shall not exceed the following maximum value of 5 snCPRI interface solution must include special dedicated hardware to perform very accurate link delay measurements.The interface shall enable periodic measurement of the cable length of each link,i.e.,measurement of the round trip group delay on the transmission medium of each link.The measurement results shall be available on the REC in order to meet the following requirements without the need to input the cable length to the REC by other meansVeEX CPRI TrainingConfidential&Proprietary Information of VeEX Inc.18What the standard saysnTests for CPRI Transport link should focus on the following:1.Verify BER requirements are met:nTest in Layer 1 unframed mode to verify CPRI physical layer with 8b/10b line coding(see CPRI protocol stack)nTest at full line rate(See CPRI rates)nUse test pattern designed to stress the 8b/10b encoding schemenCapability to detect/inject 10b code violationsnCapability to detect/inject 8b bit errors2.Measure Round Trip Link Delay:nCPRI interface specs requires CPRI hardware to be capable to periodically measure with high accuracy the delay on the transport link.nThe test set must be able to measure round trip delay so that this measure can be compared/correlated with CPRI RE/REC hardware measurements VeEX CPRI TrainingConfidential&Proprietary Information of VeEX Inc.19Test AreasTX300 CPRI Configuration and ResultsConfidential&Proprietary Information of VeEX Inc.203.072G Optical Testing option for TX300Confidential&Proprietary Information of VeEX Inc.21TX300 Test PortsOptical Test Port up to CPRI 6.14G rateScreen downXFP I/F for SMT-64/OC-192 1310 or 1550nm OTU-2,10GE/FC(option)SFP I/F for OC-3/12/48 1310 or 1550nmDual 100ohm BalancedDual DS1 Tx/RxDual 10/100/1000-TDual 1000Base-X1/2/4G Fibre Channel75ohm unbalanced Tx/Rx for DS3Optical Test Port for 9G CPRI rate.Unframed testing Rates up to 6.144Gbps.Connect to Ethernet P1testing at 9.8Gbps.CPRI L1 Framed up to 6.144GbpsConnect to OCx port.CPRI L2 up to 6.144 Gbps.Connect to OCx port L2 Main MenuL2 SetupRate SelectionMaster/Slave SelectionTest Pattern selectionCPRI C&M channel auto-negotiationL2 Rate SelectionMaster/Slave ConfigurationMaster or SlaveOnly Protocol 1 supportedSelect HDLC channel rate.If none selected,no HDLC channel usedSelect Ethernet channel pointer start place.If OFF selected,no Ethernet channel used.Note:For demo purpose,you can set the unit in Master mode with loopbackIf you select Auto-neg,the master and slave automatically negotiate their best HDLC and Ethernet channel capabilitiesAlarm and Error InjectionList of Alarms InjectionnCPRI LOS=Loss of SignalnCPRI LOF=Loss of FramingnCPRI SDI=SDI set nCPRI RAI=RAInCPRI RLOS=Remote LOS(LOS inserted in Control word)nCPRI RLOF=Remote LOF(LOF inserted in control word)List of Error InjectionnPattern,BIT:Bit error injection in test patternnCPRI,Code:Code violation error injectionService Disruption Test ConfigurationConfigure Limit and Gate TimeService Disruption Test ConfigurationConfigure CPRI SDT trigger criteriaConfigure BERT SDT trigger criteriaResultsNote:Results Saving not supported in this release.Errors/AlarmsHFN Synchronization indicationBFN(NodeB Radio Frame)Synchronization indicationFrame CountersNumber of Receive Hyperframe CounterNumber of Received NodeB Radio Frame CounterDelay MeasurementEnter Toffset reading from SlaveCable delay MeasurementSDT Test ResultsSDT Test Results3.072G Optical Testing option for TX300Confidential&Proprietary Information of VeEX Inc.38Results Summary ScreennVerify that no errors are present and the TX and RX are at 100%(3.072 Gbps)Use Tabs to access the results screensnRound Trip Delay measurement requires a loopback at the far endnUse function key RTD ON to enable the measurement3.072G Optical Testing option for TX300Confidential&Proprietary Information of VeEX Inc.39Round Trip DelayTap on key to select enabling/disabling Round trip delay measurementRound trip delay resultsConfidential&Proprietary Information of VeEX Inc.40联系信息：E-mail:何高峰：136-7126-7996