LTE基础知识

一、协议知识

1. LTE帧结构及物理资源基本概念RE/RB/CCE/REG/RBG

帧结构Type1：FDD（全双工和半双工）(FDD上下行数据在不同的频带里传输；使用成对频谱) 每一个无线帧长度为10ms，由20个时隙构成，每一个时隙长度为Tslot = 15630 x Ts = 0.5ms。

对于FDD，在每一个10ms中，有10个子帧可以用于下行传输，并且有10个子帧可以用于上行传输。上下行传输在频域上进行分开。

#0#1#2#18#19 slot Sub-frame One radio frame = 10ms

帧结构Type2：TDD (TDD上下行数据可以在同一频带内传输；可使用非成对频谱)

一个无线帧10ms，每个无线帧由两个半帧构成，每个半帧长度为5ms。每一个半帧由8个常规时隙和DwPTS、GP和UpPTS三个特殊时隙构成，DwPTS和UpPTS的长度可配置，要求DwPTS、GP以及UpPTS的总长度为1ms。

One radio frame =10 ms One half frame =5 ms

1 ms# 0# 2# 3# 4# 5# 7# 8# 9

DwPTS: Downlink Pilot Time Slot GP: Guard Period (GP越大说明小区覆盖半径越大) UpPTS: Uplink Pilot Slot

Ts = 1 / (15000x2048) s

Frame 帧的长度：Tf = 307200 x Ts = 10ms

Subframe 子帧的长度：Tsubframe = 30720 x Ts = 1ms Slot 时隙的长度：Tslot = 15360 x Ts = 0.5ms

1 Sub-Carrier = 15 kHz;

1 TTI = 1 ms => 1 sub-frame => 2 slots (0.5 ms *2) # for one user, min 2 RB allocation.

1 RB = 12 sub-carriers during 1 slot (0.5 ms) =>12 * 15kHz = 180kHz (Bandwidth); => 12 * 7 symbols= 84 REs 1 RE = 1 sub-carrier x 1 symbol period (Each symbol is QPSK, 16QAM or 64QAM modulated.)

LTE支持可变带宽：1.4MHz, 3, 5, 10, 15 和 20MHz

一个小区最少使用6个RB, 即最少包含72个sub-carriers: 6 RB * 12 sub-carriers = 72 sub-carriers 一个小区最多支持110个RB，相当于1320个sub-carriers: 110 *12 =1320 sub-carriers Channel bandwidth 1.4 3 5 10 15 20 BWChannel [MHz] Transmission bandwidth 6 15 25 50 75 100 configuration NRB DwPTSGPUpPTSDwPTSGPUpPTSNormal cyclic prefix in downlink DwPTS UpPTS Normal cyclic prefix in uplink Extended cyclic prefix in uplink Extended cyclic prefix in downlink DwPTS UpPTS Normal cyclic prefix in uplink Special subframe configuration 0 1 2 3 4 5 6 7 8 6592?Ts 19760?Ts 7680?Ts Extended cyclic prefix in uplink 2192?Ts 20480?Ts 23040?Ts 25600?Ts 2560?Ts 7680?Ts 2192?Ts 2560?Ts 21952?Ts 24144?Ts 26336?Ts 6592?Ts 19760?Ts 20480?Ts 4384?Ts 23040?Ts 4384?Ts 5120?Ts 21952?Ts 24144?Ts - 5120?Ts - - - - - 特殊帧格式5：DwPTS:GP:UpPTS => (6592Ts-16Ts) : (19744Ts-16Ts) : 4384Ts=> 3:9:2 特殊帧格式7：DwPTS:GP:UpPTS => (21952Ts-32Ts) : 4384Ts : 4384Ts=> 10:2:2 最小分配单位为: 2192?Ts

Configure TDD: 上下行配置（下图） + 特殊帧格式（上图） (e.g.: 2:7 1:7) Uplink-downlink Downlink-to-Uplink Subframe number configuration 0 1 2:2 2 3:1 3 4 5 6 Switch-point periodicity 0 1 2 3 4 5 6 7 8 9 5 ms 5 ms 5 ms 10 ms 10 ms 10 ms 5 ms D S U U U D S U U U D S U U D D S U U D D S U D D D S U D D D S U U U D D D D D D S U U D D D D D D D S U D D D D D D D D S U U U D S U U D TDD支持5ms和10ms的周期转换： => 5ms转换周期：一个帧的上下半帧的特殊帧格式配置相同，

=> 10ms转换周期：一个帧分成上下半帧，下半帧的特殊帧为DwPTS=1ms，用于DL传输(如上图3，4，5所示)

RE：Resource Element，称为资源粒子，是上下行传输使用的最小资源单位。 1 RE = 1 subcarrier x 1 symbol period

RB：Resource Block，称为资源块，用于描述物理信道到资源粒子的映射。一个RB包含若干个RE。一个RB由12个在频域上的子载波和时域上一个slot周期构成（1 RB = 12 subcarriers x 1 slot）。 1个RB在频域上对应180kHz：1 RB = 12 subcarriers x 15kHz = 180kHz 1个RB在时域上对应1个时隙，1 slot =0.5ms

CCE：Control Channel Element，称为控制信道粒子，PDCCH在一个或多个CCE上传输，CCE对应于9个REG，每个REG包含4个RE，CCE从0开始编号。（1 CCE = 9 REGs = 9 x 4 REs = 36 REs） PDCCH format与CCE之间的关系如下图所示： Number of PDCCH bits PDCCH format Number of CCEs Number of REGs (QPSK) 0 1 2 3 1 2 4 8 9 18 36 72 72 144 288 576

REG：Resource Element Group，用来定义控制信道到RE的映射.（1 REG = 4 REs）

RBG：Resource Block Group，RBG是连续的PRB的集合，其大小根据系统带宽配置的不同而定，如下图所示： System Bandwidth RBG Size (P) (Number of DL RBs) 1 ≤10 11 – 26 2 27 – 63 (e.g.: 10MHz - 50 RBs) 3 64 – 110 (e.g.: 20MHz - 100 RBs) 4

2. 下行物理信道及物理信号的功能和占用时频码域位置（DL：PDSCH/PDCCH/PHICH/PCFICH/PBCH/

PSS/SSS/RS）

Location of PBCH for FS2 (normal CP, extededCP):?SancharGmbHTDD:PCFICH PHICHSlot #0Subframe #0Slot #1SSSDwPTSPSSSpecial subframeGPUpPTSNormal CP casePDCCHS-SCHP-SCHfrequencyfrequencyPDSCHPBCHCentral 6 RBsSymbolsSlot #0Subframe #0Slot #1DwPTSSpecial subframeGPUpPTSExtended CP casePDCCHS-SCHP-SCHPDSCHPBCHCentral 6 RBsSymbolsPage 72 2.1 PBCH：Physical Broadcast Channel （物理广播信道）

- 主要用来传输MIB信息，MIB消息包含：DL带宽信息；PHICH组号；系统帧号SFN - MIB: DL-Bandwidth, PHICH-Config, SFN, # of antennas.

- 占用中间的6个RB（72sc），在第2个slot的前4个symbol上传递（slot 1, symbol 0~3）

- MIB消息的重复周期为40ms，起始位置为subfram#0 of SFN mod 4 = 0。每10ms传递一次MIB，传递内容一致，40ms组成一个MIB消息。可实现时间分集，提高UE接收MIB消息时的增益，改善接收质量

2.2 PCFICH：Physical Control Format Indicator Channel （物理控制格式指示信道） - 用来指示在一个sub-frame中PDCCH传输的OFDM symbol数量（1, 2 or 3） - 在每个subframe(TTI)的第1个symbol上进行传递(symbol 0 within each TTI) - 承载CFI信息，每TTI占用16个RE资源，即4个REG

2.3 PDCCH：Physical Downlink Control Channel （物理下行控制信道）

- 用于承载DCI信息，包括资源调度分配和其他控制信息，如与DL-SCH和PCH相关的HARQ信息等

- PDCCH在每个subframe的前3个symbol（symbol 0~2）中进行传递，占用个数由PCFICH承载的CFI消息来确定。 - PDCCH的大小对应于一个或者多个CCE，如下图所示：

PDCCH format 0 1 2 3 Number of CCEs 1 2 4 8 Number of REGs 9 18 36 72 Number of PDCCH bits 72 144 288 576 - DSS => Dedicated Search Space (for only one UE) & CSS => Common Search Space (for several UEs)

2.4 PDSCH：Physical Downlink Shared Channel （物理下行共享信道）

- 用于承载DL-SCH信息，传递SIB信息（SIB消息传递方向：BCCH -> DL-SCH -> PDSCH）

- SIB1消息的重复周期为80ms，初始位置为subframe#5 of SFN mod 8 = 0，在SFN mod 2 = 0的帧上重复. SIB – System Information Blocks

- SIB1: Cell Access Info (PLMN, TAC, CID…); 小区选择相关信息; TDD相关配置信息; 余下SIB的时域调度信息 - SIB2: 公共信道的无线资源配置（PCCH, RACH); freqInfo (ul-carrierFreq, ul-bandwidth); defaultPagingCycle - SIB3: Cell re-selection information. (Intra/Inter frequency or/and Inter-RAT cell re-selection) - SIB4: Neighbor cell related info only for Intra-frequency cell re-selection information. - SIB5: E-UTRAN Inter-frequency cell re-selection information. - SIB6: UTRAN frequencies and neighboring cell re-selection. - SIB7: GERAN frequencies cell re-selection.

- SIB8: CDMA2000 frequencies and neighbouring cell re-selection. - SIB9: Home eNB.

- SIB10: ETWS primary notification. - SIB11: ETWS secondary notification.

- PDSCH：Physical Downlink Shared Channel（物理下行共享信道） - PDCCH：Physical Downlink Control Channel（物理下行控制信道）

- PCFICH：Physical Control Format Indicator Channel（物理控制格式指示信道） - PHICH：Physical Hybrid-ARQ Indicator Channel（物理HARQ指示信道） - PMCH：Physical Multicast Channel（物理多播信道）

- PUSCH：Physical Uplink Shared Channel（物理上行共享信道） - PUCCH：Physical Uplink Control Channel（物理上行控制信道） - PRACH：Physical Random Access Channel（物理随机接入信道）

5. MIMO technology

- Two kinds of MIMO techniques for DL transmission：

o Transmit diversity – use multiple channels to send the same information stream ? Improve coverage and robustness of data transmission

o Spatial multiplexing – use multiple channels to send multiple information streams ? Increase throughput ? SU-MIMO/ MU-MIMO

- MIMO techniques according to the number of Antennas：

? SISO ? MISO ? SIMO ? MIMO

- MIMO techniques for UL transmission => MU-MIMO

Transmission Mode 与 DCI format之间的关系（传输模式信息在RRCConnectionReconfiguration 过程中指示）： Transmission mode: DCI Format: TM1 Single-antenna port; port 0 1, 1A 单天线端口传输 TM2 Transmit diversity 1, 1A 传输分集 TM3 Open-loop spatial multiplexing 2A 开环MIMO（Large delay CDD） TM4 Closed-loop spatial multiplexing 2 闭环MIMO（PMI反馈） TM5 Multi-user MIMO 1D TM6 Closed-loop Rank=1 precoding 1B TM7 Single-antenna port; port 5 1, 1A UE-specific RS，用于beamforming Transmission Number of Antenna Rank Layer Codeword Mode ports TM1 （单天线） TM2 （传输分集） 1 1 1 2 TM3 & TM4 （空分复用） 2 3 4 1 2 4 2 2 3 4 1 1 1 2 2 2 2 1 2 4 2 4 4 4

6. PDSCH下行资源分配方式（Type0/1/2）； Type 0: PDCCH DCI formats 1, 2 and 2A

RBs are grouped to RBG. RBGs are selected. System Bandwidth RBG Size (P) (Number of DL RBs) 1 ≤10 11 -– 26 2 27 – 6463 (e.g.: 10MHz - 50 RBs) 3 64 – 110 (e.g.: 20MHz - 100 RBs) 4 Type 1: PDCCH DCI formats 1, 2 and 2A

RBs are grouped to RBG subset. First select one RBG subset, then select the RBs in the RBG subset. RBG subset的值（P）与Type0中RBG的定义一致。 RBG subsets：Log2(P)

RB assignment：

Type 2: PDCCH with DCI format 1A, 1B, 1C and 1D Start RB and width is assigned.

7. DCI Format

DCI: Downlink Control Information (ref. 36.212) => Carriered by PDCCH 一个DCI传递上下行调度信息，或者针对一个RNTI的上行功率控制命令

DCI Format DCI 0 DCI 1 DCI 1A DCI 1C DCI 2 Use scope For the scheduling of PUSCH (For Uplink only) For the scheduling of one PDSCH codeword, TM1, 2 and 7 (Type0, 1) For the compact scheduling of one PDSCH codeword and random access procedure initiated by a PDCCH order, TM1~7 (Type 2) For very compact scheduling of one PDSCH codeword (Type 2) For MIMO (e.g.: CL MIMO), TM4 (Type0, 1) For the scheduling of one/two PDSCH codeword TPC command for PUCCH For MIMO (e.g.: OL MIMO), TM3 (Type0, 1) For the scheduling of one/two PDSCH codeword TPC command for PUCCH DCI 2A ? Format 0: 用于上行传输，PUSCH的调度 - Flag for format0/format1A differentiation - 1 bit, 0=>format 0 and 1=>format 1A - Resource block assignment and hoping resource allocation - Modulation and coding scheme

- HARQ information and redundancy version - TPC command for scheduled PUSCH – 2 bits - CQI request – 1bit

?

Format 1:用于传输分集，单码字PDSCH的调度 (Used for the scheduling of single codeword PDSCH) (TM1, 2, and 7-not support)

- Resource allocation type, e.g.: type 0 / type 1 – 1bit - Resource block assignment

- Modulation and coding scheme – 5 bits - HARQ process number – 4 bits - TPC command for PUCCH – 2 bits

? Format 1A: 用于下行传输，单码字PDSCH调度，下行数据触发随机接入过程，适用所有TM传输模式。=>

Compact scheduling of one PDSCH codeword and random access procedure initiated by a PDCCH order (为UE分配一个非竞争随机接入的特定preamble).

- Flag for format0/format1A differentiation - 1 bit, 0=>format 0 and 1=>format 1A - Resource block assignment

- Modulation and coding scheme – 5 bits - HARQ information – 4 bits

- TPC command for PUCCH – 2 bits

? Format 1B: Compact scheduling of one PDSCH codeword with precoding information. Closed loop precoding

with rank-1 transmission. (TM6, 目前不支持，不需要掌握)

? Format 1C: Very compact scheduling of single codeword PDSCH. (Paging, SIB, 系统广播信息 ? ) - Resource block assignment - Modulation and coding scheme - Redundancy version

? Format 1D: Compact scheduling of one PDSCH codeword with precoding and power offset information. (using

Multi-user MIMO, TM5,目前不支持)

? Format 2: For MIMO (Closed-Loop)，两码字，下行PDSCH调度 (闭环模式，TM4，需要上报PMI信息)

? Format 2A: For MIMO (Open-Loop)，两码字，下行PDSCH调度（开环模式，TM3）

?

Format 3/3A: Transmission of TPC commands for PUCCH and PUSCH with 2-bit or 1-bit power adjustments

8. LTE相关接口的控制面和用户面协议栈

Radio interface User Plane:

Control Plane: UENASeNBMMENASRRCPDCPRLCMACPHYUEPDCPRLCMACPHYeNBPDCPRLCMACPHYRRCPDCPRLCMACPHY

PHY: L1协议，

? Data Transfer via Transport Channels. ? Error Detection. Hybrid ARQ Combining. ? Channel Coding and Rate Matching. ? Modulation and Demodulation. ? Measurements.

? MIMO（多进多出）, Transmit Diversity（发送分集）, Beamforming（波速成型）. ? RF Processing.

MAC: L2协议，主要实现与调度和HARQ相关的功能

? Data Transfer via Logical Channels. ? 逻辑信道和传输信道之间的映射

? UE之间以及一个UE在不同逻辑信道之间的资源分配和调度 ? 传输格式选择 ? HARQ纠错功能

RLC: L2协议，主要实现与ARQ相关的功能，保证数据传输的可靠性

? 上层PDU数据传输: TM（透明模式）, UM（非确认模式）, AM（确认模式）数据传输 ? ARQ纠错功能（CRC检验由物理层完成） ? 串联，分段及重分段功能

? 顺序传送上层数据以及重复检测功能

PDCP: L2协议，提供ROHC可靠头压缩功能，以及加密和完整性保护功能

RRC: L3协议，提供广播、寻呼、RRC连接管理、无线承载控制、移动性、UE测量上报和控制功能等功能

NAS: 非接入层控制协议，主要实现以下功能:

? SAE承载管理 ? 鉴权

? LTE-IDLE状态下的移动性管理

? ? 产生LTE_IDLE状态下的寻呼消息 安全控制

Control Plane (eNB-MME):

S1 interfaces

User Plane (eNB-S-GW): User plane PDUs S1-AP GTP-U UDP IP Data link layer Physical layer

SCTP IP Data link layer Physical layer X2 interfaces

User Plane (eNB-eNB):

Control Plane:

User plane PDUs X2-AP GTP-U UDP IP Data link layer Physical layer

SCTP IP Data link layer Physical layer 9. LTE相关流程

9.1 Call Setup 呼叫流程

9.2 Cell Selection 小区搜索过程 9.3 Random Access 随机接入过程 - Initial access from RRC_IDLE;

- RRC Connection Re-establishment procedure; - Handover;

- DL data arrival during RRC_CONNECTED requiring random access procedure; - E.g. when UL synchronisation status is “non-synchronised”;

- UL data arrival during RRC_CONNECTED requiring random access procedure;

- E.g. when UL synchronisation status is \available.

Contention based (applicable to all five events):

UEeNBNon-contention based (Handover & DL data arrival):

1Random Access PreambleUEeNBRandom Access Response20RA Preamble assignment3Scheduled TransmissionRandom Access Preamble1Contention Resolution42Random Access Response

9.4 RRC connection establish procedure RRC连接建立过程

- SRB: Signalling Radio Bearer (Transmission of RRC&NAS messages.)

o SRB0: for RRC msg, using CCCH

o SRB1: for RRC & NAS (before SRB2 established) msg, using DCCH.

o SRB2: for NAS msg, using DCCH. Configured after security activation together with DRB. - DRB: Data Radio Bearer (Transmission of user data)

RRC Connection Setup (SRB0,1) & reconfiguration (SRB2, DRB)UEeNBMMEUL-SCH RLC TM SRB0 RRC-ConnectionRequestDL-SCH RLC TM SRB0 RRC-ConnectionSetupUL-SCH RLC AM SRB1 RRCConnectionSetupCompleteNAS(EMM Attach Request (ESM PDN CONNECTIVITYREQUEST))S1AP: INITIAL UE MESSAGE NAS (EMM Attach Request(ESM))1.0 Autenticationand 2.0 SecurityMode ProceduresS1AP: INITIAL CONTEXT SETUP REQUEST NAS (EMM Attach Accept(ESM))DL-SCH RLC AM SRB1 RRC-ConnectionReconfigurationNAS (EMM Attach Accept(ESM ACTIVATE DEFAULT EPS BEARER CONTEXT REQUEST))UL-SCH RLC AM SRB1 RRC-ConnectionReconfigurationCompleteS1AP: INITIAL CONTEXT SETUP RESPONSE UL-SCH RLC AM SRB2RRC UplinkInformationTransferNAS (EMM Attach Complete (ESM ACTIVATE DEFAULT EPS BEARER CONTEXT ACCEPT))S1AP: UPLINK NAS TRANSPORT NAS (EMM Attach Complete(ESM))IP uplinkand downlinktrafficOnly for internal usage 8?Nokia Siemens NetworksWBTS Architecture / 9/14/2010

9.5 ATTACH过程

9.6 Handover 切换过程 (6 types) - Handover types:

o Intra-eNB handover (via X2 interface)

o Inter-eNB handover (shall be via X2 interface, except some special conditions) o Inter-RAT handover (via S1 interface)

o Inter-frequency handover (applicable to above 3 types) o Intra-frequency handover (applicable to above 3 types)

二、软件框架

1. 掌握BTS包含哪些模块及其功能：

BTSOM/RROM/ENBC/CELLC/UEC/TUPC/TUPU/MAC/PHY/RFSW/TRSW； Flexi BTS –SW ArchitectureRAT specificApplication CP and UP SWShown in next slideWCDMASWLTESWGSMSWI-HSPA ADA SWBTS Common Application SWCommon Application SWTRSWDFTBTSOMUMBTS Common SW3rdparty HWSWBTS CommonPlatform SWBTSSite MgrGPSReceiverALDRFSWCommon Platform Services SWCC&SHWAPIDSP HWAPISWOS3rdpartySWRF HWFR/AASModuleHWPC/WorkstationFor internal use only13?Nokia Siemens NetworksPrimary colours:R 255 G 211 B 8R 255 G 175 B 0R 127 G 16 B 162Flexi BTS System Module HW LTE eNBSW Architecture / 2009.02.20Supporting colours:R 255 G 255 B 255R 0 G 0 B 0R 137 G 146 B 155R 163 G 166 B 173R 175 G 0 B 51R 52 G 195 B 51

1.1. BTS Common Software: ? BTS Site Manager： ? TRSW：传输模块 ? RFSW：射频模块

Platform Service SW:

? CC&S：Common Computer & Support SW

? HWAPI：Hardware Application Programming Interface (MCU environments) ? DSP HWAPI：(DSP environments)

o SW download for Faraday-chip, startup of Faraday-chip, configures and synchronizes BB bus,

maps local cells to antennas and provides monitor & test & debug services

Common Application SW:

? BTSOM：BTS level Operation & Maintenance ? DFT：Design For Testability ? UM：Unit Management

o UM is runtime SW entity that represents a HW resource (module or unit) o Unit specific O&M functions and agents o Unit level initialization and recovery o Unit level HW and SW management o Unit level fault management

1.2. LTE Specific SW:

? LTE RROM：LTE Radio Resource Operation and Maintenance

o 为Local Cell分配基带资源（local cell与global cell之间有映射关系）；

o 小区状态控制和配置处理，如：公共（common）和共享（shared）信道配置等； o 为eNB内部硬件分配逻辑资源

o BTS O&M网络配置代理，如：通过O&M配置数据获得真实的C/U面配置参数 o 提供与其他SC之间的通信通道，只有RROM知道所有SC的内部地址

o Configure signalling associations on S1 and X2 interface, and link failure handling o 通过PhyTest和MacTest控制3GPP Test Models. o RromMgmt & RromTest (BTSOM)

? LTE ENBC：LTE eNB Controller（Control function and RRM for BTS level）

o X2和S1通用信令的主要接入点，寻呼请求的分发 o S1 / X2 Reset 分布和协调，控制S1/X2建立过程 o X2 ICIC protocol handling o MME selection function

o Load control & Congestion Control (BTS level, e.g. X2 / S1 interfaces)

o 小区切换消息的转发（inter&intra eNB HO），源eNB到目标eNB或者源UEC到目标UEC. =>

EnbcSgnl (LTE UEC)

o Handling of Network and Cell Configuration, and link state changes => EnbcCrtl (LTE RROM) o C-plane control of data path failure/recovery cases, e.g.: TEID for failed user data path, UE ID for

MMEs under of S1 reset. => EnbcIdMgmt (LTE UEC)

?

LTE CELLC：LTE Cell Controller (Control function and RRM for CELL level)

o Cell级别的寻呼调度 (requires AaLteTime service from CC&S on MCU) => CellcPaging (LTE

ENBC)

o 系统信息广播，寻呼以及系统信息的RRC协议处理

o CQI configuration parameter calculation => CellcCrtl (LTE RROM) o 小区测量控制，Configuration and evaluation of Cell Measurements

o Admission Control（准入控制）and Congestion Control（拥塞控制） => CellcRrm (LTE UEC) LTE UEC：LTE User Equipment Controller (UE related control functions and RRM algorithms)

o Dedicated procedures on S1/X2/RRC interfaces => UecSgnl (LTE ENBC) o UE State and Bearer management

o 切换处理以及UE相关的S1、X2和小区重置过程 => UecHoSgnl (LTE UEC) o 执行约束控制（overload protection） o 完整性保护和加密配置

o Configuration of lower layers for all dedicated procedures (MAC, TUP, PDCP, etc.) => UecCtrl

(LTE RROM)

o Handling eNB internal dedicated UE measurements

o UE failure handling (e.g. errors reported from lower layers) o Gap Assistance LTE TUPc

o Message routing for BTS external control plane interfaces => TupSgnlNw (LTE ENBC, LTE UEC) o 主要处理SCTP传输控制 => TupLink (LTE RROM, LTE ENBC, LTE UEC)

LTE TUPu

o User plane protocols of X2 and S1(GTP-U) o PDCP protocol

LTE MAC：L2 air interface protocols

o Packet Scheduling (调度功能) o RLC and MAC protocols

o Adaptive modulation and coding (自适应编码调制技术) o Provisioning of required PM and FM data via LOM

LTE PHY：Baseband L1 (PHY) processing

o DL transport channel processing: error protection (CRC), channel encoding, rate matching, channel

interleaving.

o DL physical channel processing: synchronization and pilot signal generation, scrambling,

modulation, spatial processing (diversity, beamforming, MIMO), sub-frame mapping (multiplexing), OFDM symbol generation.

o UL physical channel processing: channelization, channel estimation, noise variance, SNR, received

signal power, frequency error and timing delay estimation, equalization, frequency error correction, demultiplexing, demodulation, descrambling. PRACH preamble detection and timing delay

estimation. UL channel quality estimation for scheduling purposes. Advanced receiver functionality (IRC, iterative equalizer and MIMO equalizer) implementation (TBD).

o UL transport channel processing : channel deinterleaving, rate dematching, HARQ combining,

decoding, error detection (CRC). o Physical layer measurements.

o OBSAI RP3 termination (UL) / generation (DL).

o Support of PhyTest interface for control of proprietary testmodels by external test tool

o Support of 3GPP compliant testmodels from INC 17 onwards (DL controled via direct interface, UL

3GPP testmodel handled by LTE MAC).

o Provisioning of required PM and FM data via LOM

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2. BTS硬件架构，掌握FCMD、FSPC的对应模块及功能部署；

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