ECPRI測(cè)試原理和測(cè)試方法專題培訓(xùn)課件

1、ECPRI測(cè)試原理和測(cè)試方法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:RF and Baseband Processing are co-located at the base of the tower. Needs to be physically located very close to the antenna because they are dr

2、iven over very lossy electrical cables.High power dissipation require costly special enclosures with climate control and power redundancyMakes it difficult to install and find a location that can host the enclosure and/or increase lease price due to additional space needed Traditional Macro-cellElec

3、trical CableCell Site CabinetMobile BackhaulRFBB2Information of VeEX Inc.Separation of RF and Baseband processing.Simplified function makes it more compact, easier to install and therefore increases the number of possible sitesFiber Link replaces COALess power required at the cell siteLess processin

4、g and power requirements at the cell siteSmaller footprint, easier to find sitesFiber allows great distance between the RRH and BBU location. All BBUs located at the CO. CPRI/OBSAI Fronthaul Network FiberMobile BackhaulRFBBMobile Fronthaul: CPRI/OBSAI3Information of VeEX Inc.Evolution of Mobile Fron

5、thaul: eCPRIWhy eCPRI?CPRI requires high data rateThis is not scalable for 5G trafficeCPRI is designed to meet the needs for 5GImproves bandwidth efficiencyIncreases capacityeCPRI uses packet-based transport network IP or EthernetMobile Fronthaul Testing4Confidential & Proprietary Information of VeE

6、X Inc. eCPRI uses packet based transport network IP or Ethernet: using a switched or routed mobile fronthaul network makes it more flexibleeCPRI uses existing standards for Transport Network Layer (Ethernet/IP)Synchronization (SyncE/PTP)C&M (SNMP, Ethernet OAM) eCPRI introduces a functional split fo

7、r baseband processing between BBU and RRH. The Functional Split defined in the protocol adapts to the application. It is a tradeoff between latency requirements and bandwidth reductionHow does eCPRI achieve this?Mobile Fronthaul Testing5Confidential & Proprietary Information of VeEX Inc.Front Haul E

8、volutionMobileBackhaulBBU PoolCPRI/OBSAI FronthaulRFRFRFBBBBBBBBMobileBackhaulBBU PoolRFBBBBBBBBBBRFBBRFBBeCPRI Fronthaul6Information of VeEX Inc.eRE = eCPRI Radio Equipment (Remote Radio Head)eREC = eCPRI Radio Equipment Controler (Baseband Unit)3 data flows between RE and REC:Synchronization traff

9、ic (1588 PTP)Control and Management TrafficUser Plane traffic (I/Q samples)eCPRI ElementseREeRECBBUSynchronizationC&M DataUser Plane data (I/Q)RRHMobile Fronthaul Transport NetworkMobile Fronthaul Testing7Confidential & Proprietary Information of VeEX Inc.eCPRI Protocol StackEthernet PHYOptional IP/

10、UDPeCPRI ProtocolI/Q User DataMobile Fronthaul Testing8Confidential & Proprietary Information of VeEX Inc.eCPRI Physical LayerThe following Ethernet interfaces are allowed in the standard:Mobile Fronthaul Testing9Confidential & Proprietary Information of VeEX Inc.How is eCPRI data Framed?Option 1: e

11、CPRI over EthernetOption 2: eCPRI over IP/UDPDestination MACSource MACType = AEFEEthernet PayloadCRCeCPRI HeadereCPRI Payload = I/Q data or control dataOptionalVLANNew eCPRI EthertypeMAC HeaderIP HeaderUDP HeaderEthernet PayloadCRCeCPRI HeadereCPRI Payload = I/Q data or control dataOptionalVLANMobil

12、e Fronthaul Testing10Confidential & Proprietary Information of VeEX Inc.Standard defines eCPRI messages for One-Way Delay Measurement between eRE/eRECeCPRI One-Way Delay measurement requires that both ends are time synchronized to the same sourceeCPRI One-Way Delay uses Delay request/ Follow-up and

13、Delay Response mechanismOne-Way Delay MeasurementMobile Fronthaul Testing11Confidential & Proprietary Information of VeEX Inc.eCPRI SynchronizationeCPRI node are frequency and phase synchronizedeRE/eREC synchronization path can be different from data patheRE/eREC synchronization from PTP/SyncEeRE sy

14、nchronization requirement more strict than eREC, because eRE generates frequency for air transmissionPTP Synchronization per ITU-T Telecom Profile Mobile Fronthaul Testing12Confidential & Proprietary Information of VeEX Inc.eCPRI Synchronization Testing RequirementsSource: Requirements for the eCPRI

15、 Transport NetworkMobile Fronthaul Testing13Confidential & Proprietary Information of VeEX Inc.Defined in the eCPRI Transport Network Requirements shall meet the following the following criteria: Transport Network Testing RequirementsMobile Fronthaul Testing14Confidential & Proprietary Information o

16、f VeEX Inc.RoE Standard: IEEE 1914.3 CPRI encapsulated into EthernetIn Process of being standardized with planned 2017 releaseRoE takes existing CPRI frames and encapsulates into Ethernet frames or alternatively takes frequency domain I/Q data and encapsulates into EthernetRoE is compatible with existing CPRI whereas eCPRI is a completely new protocol not backward compatible with CPRIPossibly RoE and eCPRI will cohabitRoE used for existi