LTE用户面培训(华为).pdf
HUAWEI TECHNOLOGIES CO.,LTDHuawei Confidential Security Level:LTE用户面培训用户面培训PDF created with FinePrint pdfFactory Pro trial version HUAWEI TECHNOLOGIES CO.,LTD.Page 2Huawei Confidential l用户面简介用户面简介l包数据汇聚层（包数据汇聚层（PDCP）l无线链路层（无线链路层（RLC）l媒体接入层（媒体接入层（MAC）PDF created with FinePrint pdfFactory Pro trial version HUAWEI TECHNOLOGIES CO.,LTD.Page 3Huawei Confidential 用户面简介PDF created with FinePrint pdfFactory Pro trial version HUAWEI TECHNOLOGIES CO.,LTD.Page 4Huawei Confidential 用户面在用户面在E-UTRAN的位置的位置PDF created with FinePrint pdfFactory Pro trial version HUAWEI TECHNOLOGIES CO.,LTD.Page 5Huawei Confidential 控制面和用户面的协议栈控制面和用户面的协议栈User-plane protocol stackcontrol-plane protocol stackPDF created with FinePrint pdfFactory Pro trial version HUAWEI TECHNOLOGIES CO.,LTD.Page 6Huawei Confidential L2的下行结构的下行结构Segm.ARQ etcMultiplexing UE1Segm.ARQ etc.HARQMultiplexing UEnHARQBCCHPCCHScheduling/Priority HandlingLogical ChannelsTransport ChannelsMACRLCSegm.ARQ etcSegm.ARQ etcPDCPROHCROHCROHCROHCRadio BearersSecuritySecuritySecuritySecurity.PDF created with FinePrint pdfFactory Pro trial version Edited by Foxit ReaderCopyright(C)by Foxit Software Company,2005-2007For Evaluation Only.HUAWEI TECHNOLOGIES CO.,LTD.Page 7Huawei Confidential L2的上行结构的上行结构Multiplexing.HARQScheduling/Priority HandlingTransport ChannelsMACRLCPDCPSegm.ARQ etcSegm.ARQ etcLogical ChannelsROHCROHCRadio BearersSecuritySecurityPDF created with FinePrint pdfFactory Pro trial version HUAWEI TECHNOLOGIES CO.,LTD.Page 8Huawei Confidential 包数据汇聚层（PDCP）PDF created with FinePrint pdfFactory Pro trial version HUAWEI TECHNOLOGIES CO.,LTD.Page 9Huawei Confidential PDCP在协议栈中的位置在协议栈中的位置User-plane protocol stackcontrol-plane protocol stackPDF created with FinePrint pdfFactory Pro trial version HUAWEI TECHNOLOGIES CO.,LTD.Page 10Huawei Confidential PDCP层的架构层的架构Radio BearersUE/E-UTRANPDCP sublayer.RLCsublayerPDCPentiyPDCP-PDURLC-SDUC-SAPPDCP-SAPPDCP-SAPRLC UM/TM-SAPRLC AM-SAP.PDCP entityPDCP entityPDF created with FinePrint pdfFactory Pro trial version HUAWEI TECHNOLOGIES CO.,LTD.Page 11Huawei Confidential PDCP 层的功能层的功能p-header compression and decompression of IP data flows using the ROHC protocol,at the transmitting and receiving entity,respectively;p-transfer of data(user plane or control plane).This function is used for conveyance of data between users of PDCP services;p-maintenance of PDCP sequence numbers for radio bearers mapped on RLC AM;p-in-sequence delivery of upper layer PDUs at handover;p-duplicate elimination of lower layer SDUs at handover for radio bearers mapped on RLC AM;p-ciphering and deciphering of user plane data and control plane data;p-integrity protection and integrity verification of control plane data;p-timer based discard;p-duplicate discarding.PDF created with FinePrint pdfFactory Pro trial version HUAWEI TECHNOLOGIES CO.,LTD.Page 12Huawei Confidential PDCP层功能层功能(控制面控制面)PDF created with FinePrint pdfFactory Pro trial version HUAWEI TECHNOLOGIES CO.,LTD.Page 13Huawei Confidential PDCP层功能层功能(用户面用户面)PDF created with FinePrint pdfFactory Pro trial version HUAWEI TECHNOLOGIES CO.,LTD.Page 14Huawei Confidential RoHC(Robust header compression)RFC 5225IP0 x0104RFC 5225ESP/IP0 x0103RFC 5225UDP/IP0 x0102RFC 5225RTP/UDP/IP0 x0101RFC 4996TCP/IP0 x0006RFC 3843,RFC4815IP0 x0004RFC 3095,RFC4815ESP/IP0 x0003RFC 3095,RFC4815UDP/IP0 x0002RFC 3095,RFC4815RTP/UDP/IP0 x0001RFC 4995No compression0 x0000ReferenceUsage:Profile IdentifierPDF created with FinePrint pdfFactory Pro trial version HUAWEI TECHNOLOGIES CO.,LTD.Page 15Huawei Confidential 加密功能加密功能l加密用户面数据和控制面数据：加密用户面数据和控制面数据：p控制面：PDCP PDU的数据部分和MAC-I部分（message authentication code）被加密；如果控制面数据没有完整性保护，则MAC-I部分仍然存在，不过值设置为0；p用户面：PDCP PDU的数据部分被加密；p加密的算法和密钥都是高层设置的，加密的激活也是由高层来做的；PDF created with FinePrint pdfFactory Pro trial version HUAWEI TECHNOLOGIES CO.,LTD.Page 16Huawei Confidential 完整性保护功能完整性保护功能l完整性保护应用于控制面数据完整性保护应用于控制面数据(SRB)p包括完整性保护和完整性验证p完整性保护的算法和密钥都是高层设置的，它的激活也是由高层来做的；PDF created with FinePrint pdfFactory Pro trial version HUAWEI TECHNOLOGIES CO.,LTD.Page 17Huawei Confidential PDCP的丢包处理：的丢包处理：lPDCP实体收到上层递交的一个PDCP SDU，就会为这个SDU启动一个Discard_Timerl当一个PDCP SDU的Discard_Timer超期时，UE就会丢弃这个PDCP SDU以及由它生成的PDCP PDU。如果这个PDCP PDU已经传递到底层的话，就向底层发一个丢弃指示命令PDF created with FinePrint pdfFactory Pro trial version HUAWEI TECHNOLOGIES CO.,LTD.Page 18Huawei Confidential PDCP Reordering windowPDF created with FinePrint pdfFactory Pro trial version HUAWEI TECHNOLOGIES CO.,LTD.Page 19Huawei Confidential 无线链路层（RLC）PDF created with FinePrint pdfFactory Pro trial version HUAWEI TECHNOLOGIES CO.,LTD.Page 20Huawei Confidential RLC在协议栈中的位置在协议栈中的位置User-plane protocol stackcontrol-plane protocol stackPDF created with FinePrint pdfFactory Pro trial version HUAWEI TECHNOLOGIES CO.,LTD.Page 21Huawei Confidential RLC的结构的结构PDF created with FinePrint pdfFactory Pro trial version HUAWEI TECHNOLOGIES CO.,LTD.Page 22Huawei Confidential TM 实体实体PDF created with FinePrint pdfFactory Pro trial version HUAWEI TECHNOLOGIES CO.,LTD.Page 23Huawei Confidential UM 实体实体PDF created with FinePrint pdfFactory Pro trial version HUAWEI TECHNOLOGIES CO.,LTD.Page 24Huawei Confidential AM 实体实体TransmissionbufferSegmentation&ConcatenationAdd RLC header Retransmission bufferRLC controlRoutingReceptionbuffer&HARQ reorderingSDU reassemblyDCCH/DTCHDCCH/DTCHAM-SAPRemove RLC header PDF created with FinePrint pdfFactory Pro trial version HUAWEI TECHNOLOGIES CO.,LTD.Page 25Huawei Confidential RLC层的功能层的功能lTransfer of upper layer PDUs;lError correction through ARQ(only for AM data transfer);lConcatenation,segmentation and reassembly of RLC SDUs(only for UM and AM data transfer);lRe-segmentation of RLC data PDUs(only for AM data transfer);lIn sequence delivery of upper layer PDUs(only for UM and AM data transfer);lDuplicate detection(only for UM and AM data transfer);lRLC SDU discard(only for UM and AM data transfer);lRLC re-establishment;lProtocol error detection and recovery.PDF created with FinePrint pdfFactory Pro trial version HUAWEI TECHNOLOGIES CO.,LTD.Page 26Huawei Confidential Segmentation/Concatenation/Re-segmentationlSegmentation就是分段，LTE中它只在UM的发送实体或者AM实体的发送侧执行。当由MAC层指示的总的RLC PDU大小小于RLC SDU时，RLC实体就会根据此情况对RLC SDU执行分段操作，让生成的RLC PDU能适配进去。lConcatenation就是串接，LTE中它只在UM的发送实体或者AM实体的发送侧执行。当由MAC层指示的总的RLC PDU大小大于RLC SDU时，RLC层就会根据此情况对RLC SDU执行串接操作，让一个RLC SDU和其他RLC SDU或者其他RLC SDU的分段串联起来，让生成的RLC PDU能适配进去。lRe-segmentation就是重分段，LTE中它只在AM实体的发送侧执行。RLC AM实体支持ARQ重传，当重传的RLC PDU无法适配到由MAC层指示的总的RLC PDU大小时，RLC层就会根据此情况对重传的RLC PDU执行分段操作，让生成的RLC PDU分段能适配进去。PDF created with FinePrint pdfFactory Pro trial version HUAWEI TECHNOLOGIES CO.,LTD.Page 27Huawei Confidential RLC AM的的ARQ功能功能lRLC AM实体的发送侧发送RLC数据PDUs到对端RLC AM实体，对端接收侧接收到RLC数据PDUs，并在以下两种情况下发送状态报告给发送侧p收到发送侧发来的Pollingp检测到RLC数据PDU接收失败l发送侧会进行重传在以下两种情况p收到接收侧发来的状态报告指示有数据包未接收成功p本发送侧底层发来的HARQ发送失败指示PDF created with FinePrint pdfFactory Pro trial version HUAWEI TECHNOLOGIES CO.,LTD.Page 28Huawei Confidential RLC AM的状态报告的状态报告l发送方触发(通过在RLC PDU中置Polling位为1来触发）p最后一个包，发方buffer中没有数据pT_Poll_Retransmit定时器超时(Polling触发后没有收到回应)p每发送完Poll_PDU个PDU后将P为置为1（PDU个数触发）p每发送完Poll_Byte个字节后将P为置为1（Byte位触发）l接收方触发p检测到接收的RLC数据PDU错误时，触发状态报告PDF created with FinePrint pdfFactory Pro trial version HUAWEI TECHNOLOGIES CO.,LTD.Page 29Huawei Confidential RLC的丢包功能的丢包功能l当收到高层丢弃指示命令丢弃特定的RLC SDU时，UM或AM RLC实体的发送端应该丢弃指示的RLC SDU(只有在该SDU还没有被映射到RLC 数据PDU中)PDF created with FinePrint pdfFactory Pro trial version HUAWEI TECHNOLOGIES CO.,LTD.Page 30Huawei Confidential 媒体接入层(MAC)PDF created with FinePrint pdfFactory Pro trial version HUAWEI TECHNOLOGIES CO.,LTD.Page 31Huawei Confidential MAC在协议栈中的位置在协议栈中的位置User-plane protocol stackcontrol-plane protocol stackPDF created with FinePrint pdfFactory Pro trial version HUAWEI TECHNOLOGIES CO.,LTD.Page 32Huawei Confidential MAC层的功能层的功能XXScheduling information reportingXXLogical Channel prioritisationXXXPriority handling between logical channels of one UEXXXPriority handling between UEsXXXTransport Format SelectionXXXXXXError correction through HARQXXXXDe-multiplexingXXXXMultiplexingXXXXXXMapping between logical channels and transport channelsUplinkDownlinkeNBUEMAC functionPDF created with FinePrint pdfFactory Pro trial version HUAWEI TECHNOLOGIES CO.,LTD.Page 33Huawei Confidential 通道和映射通道和映射DL Channel mappingUL Channel mappingPDF created with FinePrint pdfFactory Pro trial version HUAWEI TECHNOLOGIES CO.,LTD.Page 34Huawei Confidential MAC层的主要过程和操作层的主要过程和操作l随即接入过程随即接入过程 Random access procedurel不连续接收不连续接收DRXl调度调度 Schedulingl混合冗余重传混合冗余重传HARQPDF created with FinePrint pdfFactory Pro trial version HUAWEI TECHNOLOGIES CO.,LTD.Page 35Huawei Confidential RACHPDF created with FinePrint pdfFactory Pro trial version HUAWEI TECHNOLOGIES CO.,LTD.Page 36Huawei Confidential 随机接入的场景随机接入的场景lInitial access from RRC_IDLE;lInitial access after radio link failure;lUL data arrival during RRC_CONNECTED requiring random access procedure;E.g.when UL synchronisation status is non-synchronised or there are no PUCCH resources for SR available.lHandover requiring random access procedure;lDL data arrival during RRC_CONNECTED requiring random access procedure;E.g.when UL synchronisation status is“non-synchronised”;All for contention base RA;last two for non-contention based RAPDF created with FinePrint pdfFactory Pro trial version HUAWEI TECHNOLOGIES CO.,LTD.Page 37Huawei Confidential 随机接入过程随机接入过程竞争RA非竞争RA PDF created with FinePrint pdfFactory Pro trial version HUAWEI TECHNOLOGIES CO.,LTD.Page 38Huawei Confidential DRXPDF created with FinePrint pdfFactory Pro trial version HUAWEI TECHNOLOGIES CO.,LTD.Page 39Huawei Confidential DRX概念和一些定义概念和一些定义lDRXpStop monitoring PDCCH during some period of time.lPurpose of DRXpDRX functionality for RRC-CONNECTED allowing for optimised configurations that allow good UE power savings and network optimisations,for UEs introducing the possibility for better UE stand-by times without the need for going to RRC-IDLE mode to reach the goal.lOn duration TimerpUE每次从DRX醒来后维持醒着的时间,UE在该段时间内搜索PDCCHlInactivity TimerpUE在醒着时每次成功解码HARQ初始发送的PDCCH后保持active的时间lActive TimepUE从DRX醒来后保持醒着的总时间lHARQ RTT TimerpUE预期DL Retransmission到达的最少间隔时间lDRX Retransmission TimerpUE预期接收DL Retransmission的时间lDRX cycle lengthpDRX cycle length一旦配置/重配置就固定，即不会因为active time大于on duration而变化。1R2-075009 SamsungPDF created with FinePrint pdfFactory Pro trial version HUAWEI TECHNOLOGIES CO.,LTD.Page 40Huawei Confidential DRX操作的图例操作的图例pPDF created with FinePrint pdfFactory Pro trial version HUAWEI TECHNOLOGIES CO.,LTD.Page 41Huawei Confidential SchedulingPDF created with FinePrint pdfFactory Pro trial version HUAWEI TECHNOLOGIES CO.,LTD.Page 42Huawei Confidential 调度调度l目的目的p调度的好坏对于系统的性能影响很大，对于LTE十分重要p最好的利用时/频/空/功率资源用于不同的UEs和不同的业务，保证各种业务的Qos，提高系统的容量l基本调度原则基本调度原则peNB负责上下性的调度，上下行是不同的调度器负责p调度器需要考虑的因素包括业务的Qos，业务量以及相关的无线承载，无线条件以及UE能力等p给于UE的UL-SCH的资源是对应一个UE的，而不是对应一个RB的PDF created with FinePrint pdfFactory Pro trial version HUAWEI TECHNOLOGIES CO.,LTD.Page 43Huawei Confidential 调度调度方式方式l动态调度动态调度p对于UL-SCH 和 DL-SCH是最基本的调度方式l半静态调度半静态调度p是一种优化的方式（例如对于UL&DL VoIP)pRRC信令负责静态调度参数(周期)的配置.pPDCCH信令复杂激活/去激活半静态调度资源PDF created with FinePrint pdfFactory Pro trial version HUAWEI TECHNOLOGIES CO.,LTD.Page 44Huawei Confidential 动动态调度过程图例态调度过程图例PDF created with FinePrint pdfFactory Pro trial version Edited by Foxit ReaderCopyright(C)by Foxit Software Company,2005-2007For Evaluation Only.HUAWEI TECHNOLOGIES CO.,LTD.Page 45Huawei Confidential HARQPDF created with FinePrint pdfFactory Pro trial version HUAWEI TECHNOLOGIES CO.,LTD.Page 46Huawei Confidential HARQ基本基本原原理理lFast retransmission/combination gainlN-process Stop-And-Wait lFor DL:pAsynchronous adaptive HARQpUL ACK/NAK on PUCCH/PUSCHpPDCCH signals HARQ process numberpRetransmissions are always scheduled through PDCCHlFor UL:pSynchronous HARQ pMAX TX number configured per UE(not per RB)pDL ACK/NAK on PHICHPDF created with FinePrint pdfFactory Pro trial version HUAWEI TECHNOLOGIES CO.,LTD.Page 47Huawei Confidential Any question?PDF created with FinePrint pdfFactory Pro trial version HUAWEI TECHNOLOGIES CO.,LTDHuawei Confidential Security Level:Thank YPDF created with FinePrint pdfFactory Pro trial version
