LTE测量事件汇总(打印)

(完整版)LTE路测问题分析归纳汇总

LTE路测问题分析归纳汇总一、Probe测试需要重点关注参数无线参数介绍➢PCC:表示主载波，SCC：表示辅载波，目前LTE(R9版本)都采用单载波的，到4G（R10版本）有多载波联合技术就表示辅载波。

➢PCI:物理小区标示，范围（0-503）共计504个。

➢RSRP：参考信号接收电平，基站的发射功率，范围：-55 < RSRP <-75dbm。

➢RSSQ：参考信号接收质量，是RSRP和RSSI的比值，当然因为两者测量所基于的带宽可能不同，会用一个系数来调RSRQ=N*RSRP/RSSI。

➢RSSI：接收信号强度指示，表示UE所接收到所有信号的叠加。

➢SINR：信噪比，是接收到的有用信号的强度与接收到的干扰信号（噪声和干扰）的强度的比值，Average SINR>20➢Transmission mode:传送模式，一共有8种，TM1表示单天线传送数据，TM2表示传输分集（2个天线传送相同的数据，在无线环境差（RSRP和SINR差）情况下，适合在边缘地带），TM3表示开环空间复用（2个天线传送不同的数据，速率可以提升1倍），TM4表示闭环环空间复用，TM5表示多用户 mimo,TM6表示rank=1的闭环预编码，TM7表示使用单天线口（单流BF），TM8表示双流BF。

Transmission mode=TM3。

➢Rank Indicator：表示层的意思，rank1表示单层，速率低，rank2表示2层，速率高。

Rank Indicator = Rank 2➢PDSCH RB number：表示该用户使用的RB数。

这个值看出，该扇区下大概有几个用户。

（20M带宽对应100个RB，15M带宽对应75个RB,10M带宽对应50个RB,5M带宽对应25个RB，3M带宽对应15个RB，1.4M带宽对应6个RB）多用户可以造成速率低原因之一。

➢PDCCH DL Grant Count：下行时域（子帧）调度数，PDCCH DL Grant Count >950。

LTE系统事件简介

LTE系统事件简介一、LTE事件概述LTE切换时需要UE上报测量的结果（包括RSRP，RSRQ等），而上报又分为周期性上报和事件触发的上报。

➢周期性上报由基站配置，UE直接上报测量的结果。

➢事件触发的上报又分为系统内的事件和系统间的事件。

LTE系统内切换主要事件包括：➢A1事件，服务小区质量高于门限；这个事件可以用来关闭频间测量。

➢A2事件，服务小区质量低于门限；这个事件可以用来打开频间测量和系统间测量，因为这个事件发生后可能发生切换等操作。

➢A3事件，邻小区质量好于服务小区质量；这个事件一般用于频内/间基于覆盖的切换。

➢A4事件，邻小区质量好于门限；这个事件一般用于基于负荷的切换。

➢A5事件，服务小区质量低于一个门限并且邻小区质量高于一个门限；这个事件也可以用于频内/间基于覆盖的切换。

目前LTE同频切换都是基于A3/A5事件进行的切换（现网主要是基于A3事件的）二、切换流程举例三、切换流程简要说明- RRC Connection Reconfiguration（Measurement Control）测量控制，一般在初始接入或上一次切换命令中的重配消息里携带- Measurement Report测量报告，终端根据当前小区的测量控制信息，将符合切换门限的小区进行上报- HO Request源小区在收到测量报告后向目标小区申请资源及配置信息（站内切换的话为站内交互，站间切换会使用X2口或者S1口，优先使用X2口）- HO Request Ack目标小区将终端的接纳信息以及其它配置信息反馈给源小区- RRC Connection Reconfiguration（HO Command）将目标小区的接纳信息及配置信息发给终端，告知终端目标小区已准备好终端接入，重配消息里包含目标小区的测量控制- SN Status Transfer源小区将终端业务的缓存数据移至目标小区- Random Access Preamble终端收到第5步重配消息（切换命令）后使用重配消息里的接入信息进行接入- Random Access Response目标小区接入响应，收到此命令后可认为接入完成了，然后终端在RRC层上发重配完成消息（第9步）- RRC Connect Reconfiguration complete（HO Confirm）上报重配完成消息，切换完成- Release Resource当终端成功接入后，目标小区通知源小区删除终端的上下文信息四、协议对LTE事件的定义和说明4.1 A1事件定义Event A1 (Serving becomes better than threshold)The UE shall:1> consider the entering condition for this event to be satisfied when condition A1-1, as specifiedbelow, is fulfilled;1> consider the leaving condition for this event to be satisfied when condition A1-2, as specifiedbelow, is fulfilled;1> for this measurement, consider the primary or secondary cell that is configured on the frequencyindicated in the associated measObjectEUTRA to be the serving cell;Inequality A1-1 (Entering condition)-Ms>HysThreshInequality A1-2 (Leaving condition)Ms<+ThreshHysThe variables in the formula are defined as follows:Ms is the measurement result of the serving cell, not taking into account any offsets.Hys is the hysteresis parameter for this event (i.e. hysteresis as defined within reportConfigEUTRA for this event).Thresh is the threshold parameter for this event (i.e. a1-Threshold as defined within reportConfigEUTRA for this event).Ms is expressed in dBm in case of RSRP, or in dB in case of RSRQ.Hys is expressed in dB.Thresh is expressed in the same unit as Ms.4.2 A2事件定义Event A2 (Serving becomes worse than threshold)The UE shall:1> consider the entering condition for this event to be satisfied when condition A2-1, as specifiedbelow, is fulfilled;1> consider the leaving condition for this event to be satisfied when condition A2-2, as specifiedbelow, is fulfilled;1> for this measurement, consider the primary or secondary cell that is configured on the frequencyindicated in the associated measObjectEUTRA to be the serving cell;Inequality A2-1 (Entering condition)+Ms<HysThreshInequality A2-2 (Leaving condition)Ms>-HysThreshThe variables in the formula are defined as follows:Ms is the measurement result of the serving cell, not taking into account any offsets.Hys is the hysteresis parameter for this event (i.e. hysteresis as defined within reportConfigEUTRA for this event).Thresh is the threshold parameter for this event (i.e. a2-Threshold as defined within reportConfigEUTRA for this event).Ms is expressed in dBm in case of RSRP, or in dB in case of RSRQ.Hys is expressed in dB.Thresh is expressed in the same unit as Ms.4.3 A3事件定义Event A3 (Neighbour becomes offset better than PCell)The UE shall:1> consider the entering condition for this event to be satisfied when condition A3-1, as specifiedbelow, is fulfilled;1> consider the leaving condition for this event to be satisfied when condition A3-2, as specifiedbelow, is fulfilled;NOTE The cell(s) that triggers the event is on the frequency indicated in the associated measObject which may be different from the (primary) frequency used by the PCell.Inequality A3-1 (Entering condition)++>+Mn++-OcnOfpOcpMpHysOffOfnInequality A3-2 (Leaving condition)++<Mn++++MpOcpOfnOfpOffHysOcnThe variables in the formula are defined as follows:Mn is the measurement result of the neighbouring cell, not taking into account any offsets.Ofn is the frequency specific offset of the frequency of the neighbour cell (i.e. offsetFreq as defined within measObjectEUTRA corresponding to the frequency of the neighbour cell).Ocn is the cell specific offset of the neighbour cell (i.e. cellIndividualOffset as defined within measObjectEUTRA corresponding to the frequency of the neighbour cell), and set to zero if not configured for the neighbour cell.Mp is the measurement result of the PCell, not taking into account any offsets.Ofp is the frequency specific offset of the primary frequency (i.e. offsetFreq as defined within measObjectEUTRA corresponding to the primary frequency).Ocp is the cell specific offset of the PCell (i.e. cellIndividualOffset as defined within measObjectEUTRA corresponding to the primary frequency), and is set to zero if not configured for the PCell.Hys is the hysteresis parameter for this event (i.e. hysteresis as defined within reportConfigEUTRA for this event).Off is the offset parameter for this event (i.e. a3-Offset as defined within reportConfigEUTRA for this event).Mn, Mp are expressed in dBm in case of RSRP, or in dB in case of RSRQ.Ofn, Ocn, Ofp, Ocp, Hys, Off are expressed in dB.4.4 A4事件定义Event A4 (Neighbour becomes better than threshold)The UE shall:1> consider the entering condition for this event to be satisfied when condition A4-1, as specifiedbelow, is fulfilled;1> consider the leaving condition for this event to be satisfied when condition A4-2, as specifiedbelow, is fulfilled;Inequality A4-1 (Entering condition)-+Mn>+HysThreshOcnOfnInequality A4-2 (Leaving condition)Mn<+++ThreshOfnHysOcnThe variables in the formula are defined as follows:Mn is the measurement result of the neighbouring cell, not taking into account any offsets.Ofn is the frequency specific offset of the frequency of the neighbour cell (i.e. offsetFreq as defined within measObjectEUTRA corresponding to the frequency of the neighbour cell).Ocn is the cell specific offset of the neighbour cell (i.e. cellIndividualOffset as defined within measObjectEUTRA corresponding to the frequency of the neighbour cell), and set to zero if not configured for the neighbour cell.Hys is the hysteresis parameter for this event (i.e. hysteresis as defined within reportConfigEUTRA for this event).Thresh is the threshold parameter for this event (i.e. a4-Threshold as defined within reportConfigEUTRA for this event).Mn is expressed in dBm in case of RSRP, or in dB in case of RSRQ.Ofn, Ocn, Hys are expressed in dB.Thresh is expressed in the same unit as Mn.4.5 A5事件定义Event A5 (PCell becomes worse than threshold1 and neighbour becomes better than threshold2)The UE shall:1> consider the entering condition for this event to be satisfied when both condition A5-1 andcondition A5-2, as specified below, are fulfilled;1> consider the leaving condition for this event to be satisfied when condition A5-3 or condition A5-4, i.e. at least one of the two, as specified below, is fulfilled;NOTE: The cell(s) that triggers the event is on the frequency indicated in the associatedmeasObject which may be different from the (primary) frequency used by the PCell.Inequality A5-1 (Entering condition 1)1Thresh Hys Mp <+Inequality A5-2 (Entering condition 2)2Thresh Hys Ocn Ofn Mn >-++Inequality A5-3 (Leaving condition 1)1Thresh Hys Mp >-Inequality A5-4 (Leaving condition 2)2Thresh Hys Ocn Ofn Mn <+++The variables in the formula are defined as follows:Mp is the measurement result of the PCell, not taking into account any offsets.Mn is the measurement result of the neighbouring cell, not taking into account any offsets.Ofn is the frequency specific offset of the frequency of the neighbour cell (i.e. offsetFreq as defined within measObjectEUTRA corresponding to the frequency of the neighbour cell).Ocn is the cell specific offset of the neighbour cell (i.e. cellIndividualOffset as defined within measObjectEUTRA corresponding to the frequency of the neighbour cell), and set to zero if not configured for the neighbour cell.Hys is the hysteresis parameter for this event (i.e. hysteresis as defined within reportConfigEUTRA for this event).Thresh1 is the threshold parameter for this event (i.e. a5-Threshold1 as defined within reportConfigEUTRA for this event).Thresh2 is the threshold parameter for this event (i.e. a5-Threshold2 as defined within reportConfigEUTRA for this event).Mn, Mp are expressed in dBm in case of RSRP, or in dB in case of RSRQ.Ofn, Ocn, Hys are expressed in dB.Thresh1 is expressed in the same unit as Mp .Thresh2 is expressed in the same unit as Mn .Event A6 (Neighbour becomes offset better than SCell)The UE shall:1> consider the entering condition for this event to be satisfied when condition A6-1, as specifiedbelow, is fulfilled;1> consider the leaving condition for this event to be satisfied when condition A6-2, as specifiedbelow, is fulfilled;1> for this measurement, consider the (secondary) cell that is configured on the frequency indicatedin the associated measObjectEUTRA to be the serving cell;NOTE: The neighbour(s) is on the same frequency as the SCell i.e. both are on the frequency indicated in the associated measObject.Inequality A6-1 (Entering condition)+>Mn++-MsOcsOffHysOcnInequality A6-2 (Leaving condition)+<+Mn++OcsOffMsHysOcnThe variables in the formula are defined as follows:Mn is the measurement result of the neighbouring cell, not taking into account any offsets.Ocn is the cell specific offset of the neighbour cell (i.e. cellIndividualOffset as defined within measObjectEUTRA corresponding to the frequency of the neighbour cell), and set to zero if not configured for the neighbour cell.Ms is the measurement result of the serving cell, not taking into account any offsets.Ocs is the cell specific offset of the serving cell (i.e. cellIndividualOffset as defined within measObjectEUTRA corresponding to the serving frequency), and is set to zero if not configured for the serving cell.Hys is the hysteresis parameter for this event (i.e. hysteresis as defined within reportConfigEUTRA for this event).Off is the offset parameter for this event (i.e. a6-Offset as defined within reportConfigEUTRA for this event).Mn, Ms are expressed in dBm in case of RSRP, or in dB in case of RSRQ.Ocn, Ocs, Hys, Off are expressed in dB.Event B1 (Inter RAT neighbour becomes better than threshold)The UE shall:1> for UTRA and CDMA2000, only trigger the event for cells included in the correspondingmeasurement object;1> consider the entering condition for this event to be satisfied when condition B1-1, as specifiedbelow, is fulfilled;1> consider the leaving condition for this event to be satisfied when condition B1-2, as specifiedbelow, is fulfilled;Inequality B1-1 (Entering condition)Thresh+Mn>-HysOfnInequality B1-2 (Leaving condition)++Mn<ThreshHysOfnThe variables in the formula are defined as follows:Mn is the measurement result of the inter-RAT neighbour cell, not taking into account any offsets.For CDMA 2000 measurement result, pilotStrength is divided by -2.Ofn is the frequency specific offset of the frequency of the inter-RAT neighbour cell (i.e. offsetFreq as defined within the measObject corresponding to the frequency of the neighbour inter-RAT cell).Hys is the hysteresis parameter for this event (i.e. hysteresis as defined withinreportConfigInterRAT for this event).Thresh is the threshold parameter for this event (i.e. b1-Threshold as defined within reportConfigInterRAT for this event). For CDMA2000, b1-Threshold is divided by -2.Mn is expressed in dBm or in dB, depending on the measurement quantity of the inter-RAT neighbour cell.Ofn, Hys are expressed in dB.Thresh is expressed in the same unit as Mn.4.8 B2事件定义Event B2 (PCell becomes worse than threshold1 and inter RAT neighbour becomes better than threshold2)The UE shall:1> for UTRA and CDMA2000, only trigger the event for cells included in the correspondingmeasurement object;1> consider the entering condition for this event to be satisfied when both condition B2-1 andcondition B2-2, as specified below, are fulfilled;1> consider the leaving condition for this event to be satisfied when condition B2-3 or conditionB2-4, i.e. at least one of the two, as specified below, is fulfilled;Inequality B2-1 (Entering condition 1)+HysMp<Thresh1Inequality B2-2 (Entering condition 2)-+Mn>Ofn2ThreshHysInequality B2-3 (Leaving condition 1)Hys-Mp>1ThreshInequality B2-4 (Leaving condition 2)Mn<++OfnHys2ThreshThe variables in the formula are defined as follows:Mp is the measurement result of the PCell, not taking into account any offsets.Mn is the measurement result of the inter-RAT neighbour cell, not taking into account any offsets.For CDMA2000 measurement result, pilotStrength is divided by -2.Ofn is the frequency specific offset of the frequency of the inter-RAT neighbour cell (i.e. offsetFreq as defined within the measObject corresponding to the frequency of the inter-RAT neighbourcell).Hys is the hysteresis parameter for this event (i.e. hysteresis as defined withinreportConfigInterRAT for this event).Thresh1 is the threshold parameter for this event (i.e. b2-Threshold1 as defined within reportConfigInterRAT for this event).Thresh2 is the threshold parameter for this event (i.e. b2-Threshold2 as defined within reportConfigInterRAT for this event). For CDMA2000, b2-Threshold2 is divided by -2.Mp is expressed in dBm in case of RSRP, or in dB in case of RSRQ.Mn is expressed in dBm or dB, depending on the measurement quantity of the inter-RAT neighbour cell.Ofn, Hys are expressed in dB.修正版Thresh1 is expressed in the same unit as Mp. Thresh2 is expressed in the same unit as Mn.。

A1-B2事件

LTE支持的切换事件有A类和B类，其中A类本用作系统内测量，B类被用作系统间测量A1事件：表示服务小区信号质量高于一定门限；A2事件：表示服务小区信号质量低于一定门限；A3事件：表示邻区质量高于服务小区质量，用于同频、异频的基于覆盖的切换； A4事件：表示邻区质量高于一定门限，用于基于负荷的切换，可用于负载均衡；A5事件：表示服务小区质量低于一定门限并且邻区质量高于一定门限，可用于负载均衡; 异系统测量事件：B1事件：邻小区质量高于一定门限，用于测量高优先级的异系统小区；B2事件：服务小区质量低于一定门限，并且邻小区质量高于一定门限，用于相同或较低优先级的异系统小区的测量。

LTE移动性参数(全局)最小接入电平基本信息参数功能该参数表示UE在该小区驻留需满足的最小接收电平门限。

该值取值范围是2G/3G接收电平的实际值，对于LTE/3G , 实际的RxlevMin 等于SIB3/SIB6的IE value的两倍，调整步长为2dbm。

对于2G，实际的RxlevMin等于SIB7的(IE value * 2) - 115，调整步长为2dBm当UE测量到的2G/3G电平满足S准则时，UE才可能驻留在该小区。

参数调整影响调整该参数的门限值，会对小区的选择和驻留有所影响。

QrxLevMin如果设置过高，则UE将无法驻留到该小区。

2高优先级重选门限基本信息参数功能当高优先级小区的S值在一定时间内高于该阀值(threshXHigh)后，UE可以重选到该小区。

参数调整影响调整该参数的门限值，会对小区的选择和驻留有所影响。

threshXhigh如果设置过高，会增加UE重选到高优先级小区的难度。

3低优先级重选门限基本信息参数功能当低优先级小区的S值在一定时间内高于该阀值(threshXLow)后，同时主服务小区的S值低于threshServingLow，UE可以重选到该低优先级小区。

参数调整影响调整该参数的门限值，会对小区的选择和驻留有所影响。

LTE切换事件介绍

Ocn：邻小区个性偏移（CIO）
Hys(5)：A5事件迟滞参数 Thersh1:A5事件门限1参数 Thersh2:A5事件门限2参数
B1事件的切换参数配置
B1事件表示：异系统邻区质量高于一个绝对门限，满足事件触发条件的小区信息被上报时，源eNodeB启动异系统切换请求，用于基于负荷的切换 B1事件判决公式：触发条件： Mn + Ofn - Hys(b1) > Thersh(b1) 取消条件：Mn + Ofn + Hys(b1) > Thersh(b1) 其中： Mn:邻小区测量结果 Ofn：邻小区频率特定的偏差，默认为0
根据A1事件触发条件：Ms – Hys(1) > Thersh(1）可以算出： Ms>-86时关闭异频测量。根据A2事件触发条件：Ms + Hys(2) < Thersh(2) 可以算出： Ms<-92时开启异频测量则当UE测量到的A小区RSRP值为红色区域时，UE不进行异频测量；当 UE测量到的A小区RSRP值为绿色区域时，UE进行异频测量；当UE测量到的A 小区RSRP值为黄色区域时，UE是否进行异频测量取决于UE之前的状态，即 UE的测量状态并不改变。
频内/频间基于覆盖的切换 B1事件：异系统邻区质量高于一个绝对门限，用于基于负荷的切换。
B2事件：服务小区质量低于一个绝对门限1且异系统邻区质量高于一个绝对门限2，
用于基于覆盖的切换。
A1事件的切换参数配置
A1事件触发条件：Ms – Hys(1) > Thersh(1） A1事件取消条件：Ms + Hys(2) < Thersh(2) 其中： Ms:服务小区测量结果 Hys(1)：A1事件迟滞参数 Hys(2)：A2事件迟滞参数 Thersh（1）:A1事件门限参数 Thersh（2）:A2事件门限参数

LTE的测量

UE（终端）站） – 测量配置放在RRC Connection Reconfiguration消息内建立RRC连接（即UE进入激活态）
RRC连接重配（包括LTE内测量配置信息）
– 切换时可以在切换命令中传递目标小区的测量控制信息给UE – 有针对UE移动速度的 3级缩放比参数: Time to trigger，以及其它 IDLE态小区重选参数
UpPTS
PCFICH（定义PDCCH格式）
R0
PDCCH（UE标识+上行资源指示）
DwPTS GP UpPTS
PHICH (HARQ指示)
R0 R0 R0
RS参考信号（测量用）
系统带宽20M
R0
R0
R0
R0
6个RB =1.08M
1个RB =180K =12个子载波
R0
l0
1个子载波 = 15K
•
•
对周期上报：则UE定时上报测量给eNB
对事件上报：判断事件在一段时间内是否满足，比如：邻区信号质量 > 服务小区信号质量＋某些偏移值，上报A3事件
–
D：UE上报测量报告给基站。
parameters
parameters
A
Layer 1 filtering
B
Layer 3 filtering
C C'
R0
R0
R0
R0
......
R0
l6 l0
R0
l6 l0
R0
l6 l0 l6
一个RE（Resource Element）
Cyclic Prefix
Page 9
测量参数的定义
– S-measure：当服务小区质量好过这个阈值，UE可以不做任何邻区测量 – Time to trigger：有针对UE移动速度的3级缩放比参数: ，以及其它IDLE态小区重选参数 – 测量带宽：一般只测量频段中心的6个RB约1.08MHz。除非设定了更宽的测量带宽 – RSRP: Reference Signal Received Power

LTE案例库总结

LTE案例库总结1.LTE下载速率低原因及相关案例 (5)1.1无线环境 (5)1.1.1案例1：系统外干扰（DCS1800）导致LTE宏站单小区下载速率低 (6)1.1.2案例2：服务小区与邻小区PCI存在mod3干扰造成下载速率过低 (8)1.1.3案例3：由GPS失锁引起的F频段LTE基站上行干扰 (9)1.2容量 (10)1.3无线参数配置 (10)1.3.1案例4：爱立信小区上下行时隙配比错误导致上行高BLER 速率低 (10)1.3.2案例5：LTE的功率PA、PB参数设置不合理导致下载速率低的处理 (11)1.3.3案例6：爱立信LTE小区DLTARGETBLER参数配置有误导致下行速率低121.3.4案例7：华为eNodeB升级8.0版本默认开启MR功能后导致速率低 (12)1.3.5案例8：由于PDCCH信道误码率较高导致下载速率波动 (13)1.3.6案例9：TA同步功能未打开导致LTE下载速率抖降问题案例(14)1.4传输问题 (14)1.4.1案例10：LTE传输问题导致小区下载速率低 (14)1.5传输参数问题 (15)1.5.1案例11：PTNQOS参数限制导致LTE下载速度低案例 (15)1.5.2案例12：PTN侧MAC地址学习功能未配置导致LTE基站FTP下载速率低161.5.3案例13：由交换机端口配置不正确导致LTE TDD下载速率波动问题 (17)1.6核心网参数 (17)1.6.1案例14：QCI设置错误导致演示厅LTE下行速率低问题 (17)1.7基站存在故障或告警 (19)1.7.1案例15：室分场景多RRU合并后某一RRU驻波导致速率低(19)1.8其它类别 (19)1.8.1案例16：LTE测试软件配置错误导致下载速率低 (19)1.8.2案例17：由于合路器接法不正确引起的下载速率低的问题(20)1.8.3案例18：LTE室分双路不平衡导致下载速率低 (22)2.LTE基站小区无法建立或建立异常问题及案例 (23)2.1无线参数配置 (23)2.1.1案例1：GPS数据配置错误导致LTE TDD无法正常开通的案例 (23)2.1.2案例2：LTE宏站小区CRS端口配置错误导致小区无法建立(24)2.1.3案例3：LTE小区与RRU关联错误导致覆盖接反 (25)2.1.4案例4：LTE基站eNodeB ID标识不唯一导致基站S1偶联链路频繁规律闪断(26)2.1.5案例5：大唐和华为GTP-U检测功能参数协商不一致导致LTE站点业务频繁中断 (26)2.1.6案例6：由于TDS频点设置问题导致LTE基站无法开启的案例 (27)3.LTE切换问题及案例 (28)3.1覆盖 (28)3.1.1案例1：由于弱覆盖导致成都理工大学LTE小区1与音乐公园LTE小区2切换失败案例 (28)3.2无线参数配置 (29)3.2.1案例2：爱立信LTE小区DCI配置错误导致切换失败 (29)3.2.2案例3：开启防乒乓切换开关导致不切换 (29)3.2.3案例4：由切换门限设置错误导致某LTE站无法进行异频切换 (30)3.2.4案例5：TAU与X2切换冲突导致切换失败并掉线 (31)3.3核心网参数 (32)3.3.1案例6：LTE核心网鉴权关闭导致切换失败 (32)3.4传输参数 (32)3.4.1案例7：LTE基站S1口少配导致切换成功率低处理案例 (32)3.5异厂家参数配置 (33)3.5.1案例8：爱立信与中兴LTE邻小区RLC传输模式配置不一致导致切换失败333.5.2案例9：大唐与诺西Local Cell Resource ID配置不一致导致切换失败的案例343.5.3案例10：由于DRB-ID分配策略华为中兴LTE异厂家切换失败案例 (35)4.LTE终端接入问题 (35)4.1无线参数配置 (35)4.1.1案例1：TD-LTE帧同步参数配置错误导致上行干扰，造成终端有信号无法接入 (35)4.1.2案例2：TDL完整性保护算法设置错误导致部分终端无法上网 (36)4.1.3案例3：爱立信室分小区PrachConfigIndex配置错误导致接入性差 (37)4.2核心网配置 (38)4.2.1案例4：LTE的S1口IP配置错误导致终端无法正常接入 (38)4.2.2案例5：在MME中未绑定IMSI和HSS对应关系导致LTE 新号段无法附着到网络 (39)4.3传输参数配置 (40)4.3.1案例6：未设置用户面路由导致LTE基站无业务速率 (40)5.2/3/4G互操作问题 (40)5.1.1案例1：由于3G/4G的PLMN不同且未配置EHPLMN导致TD-S重选TD-L失败 (40)5.1.2案例2：华为和中兴MME选路策略不同导致CSFB被叫接通率较低 (41)6.掉话问题 (43)6.1.1案例1：TD-LTE SRS带宽重配置导致掉话率高案例 (43)。

LTE系统事件简介

LTE系统事件简介一、LTE事件概述LTE切换时需要UE上报测量的结果（包括RSRP，RSRQ等），而上报又分为周期性上报和事件触发的上报。

➢周期性上报由基站配置，UE直接上报测量的结果。

➢事件触发的上报又分为系统内的事件和系统间的事件。

LTE系统内切换主要事件包括：➢A1事件，服务小区质量高于门限；这个事件可以用来关闭频间测量。

➢A2事件，服务小区质量低于门限；这个事件可以用来打开频间测量和系统间测量，因为这个事件发生后可能发生切换等操作。

➢A3事件，邻小区质量好于服务小区质量；这个事件一般用于频内/间基于覆盖的切换。

➢A4事件，邻小区质量好于门限；这个事件一般用于基于负荷的切换。

➢A5事件，服务小区质量低于一个门限并且邻小区质量高于一个门限；这个事件也可以用于频内/间基于覆盖的切换。

目前LTE同频切换都是基于A3/A5事件进行的切换（现网主要是基于A3事件的）二、切换流程举例三、切换流程简要说明- RRC Connection Reconfiguration（Measurement Control）测量控制，一般在初始接入或上一次切换命令中的重配消息里携带- Measurement Report测量报告，终端根据当前小区的测量控制信息，将符合切换门限的小区进行上报- HO Request源小区在收到测量报告后向目标小区申请资源及配置信息（站内切换的话为站内交互，站间切换会使用X2口或者S1口，优先使用X2口）- HO Request Ack目标小区将终端的接纳信息以及其它配置信息反馈给源小区- RRC Connection Reconfiguration（HO Command）将目标小区的接纳信息及配置信息发给终端，告知终端目标小区已准备好终端接入，重配消息里包含目标小区的测量控制- SN Status Transfer源小区将终端业务的缓存数据移至目标小区- Random Access Preamble终端收到第5步重配消息（切换命令）后使用重配消息里的接入信息进行接入- Random Access Response目标小区接入响应，收到此命令后可认为接入完成了，然后终端在RRC层上发重配完成消息（第9步）- RRC Connect Reconfiguration complete（HO Confirm）上报重配完成消息，切换完成- Release Resource当终端成功接入后，目标小区通知源小区删除终端的上下文信息四、协议对LTE事件的定义和说明4.1 A1事件定义Event A1 (Serving becomes better than threshold)The UE shall:1> consider the entering condition for this event to be satisfied when condition A1-1, as specifiedbelow, is fulfilled;1> consider the leaving condition for this event to be satisfied when condition A1-2, as specifiedbelow, is fulfilled;1> for this measurement, consider the primary or secondary cell that is configured on the frequencyindicated in the associated measObjectEUTRA to be the serving cell;Inequality A1-1 (Entering condition)-Ms>HysThreshInequality A1-2 (Leaving condition)Ms<+ThreshHysThe variables in the formula are defined as follows:Ms is the measurement result of the serving cell, not taking into account any offsets.Hys is the hysteresis parameter for this event (i.e. hysteresis as defined within reportConfigEUTRA for this event).Thresh is the threshold parameter for this event (i.e. a1-Threshold as defined within reportConfigEUTRA for this event).Ms is expressed in dBm in case of RSRP, or in dB in case of RSRQ.Hys is expressed in dB.Thresh is expressed in the same unit as Ms.4.2 A2事件定义Event A2 (Serving becomes worse than threshold)The UE shall:1> consider the entering condition for this event to be satisfied when condition A2-1, as specifiedbelow, is fulfilled;1> consider the leaving condition for this event to be satisfied when condition A2-2, as specifiedbelow, is fulfilled;1> for this measurement, consider the primary or secondary cell that is configured on the frequencyindicated in the associated measObjectEUTRA to be the serving cell;Inequality A2-1 (Entering condition)+Ms<HysThreshInequality A2-2 (Leaving condition)Ms>-HysThreshThe variables in the formula are defined as follows:Ms is the measurement result of the serving cell, not taking into account any offsets.Hys is the hysteresis parameter for this event (i.e. hysteresis as defined within reportConfigEUTRA for this event).Thresh is the threshold parameter for this event (i.e. a2-Threshold as defined within reportConfigEUTRA for this event).Ms is expressed in dBm in case of RSRP, or in dB in case of RSRQ.Hys is expressed in dB.Thresh is expressed in the same unit as Ms.4.3 A3事件定义Event A3 (Neighbour becomes offset better than PCell)The UE shall:1> consider the entering condition for this event to be satisfied when condition A3-1, as specifiedbelow, is fulfilled;1> consider the leaving condition for this event to be satisfied when condition A3-2, as specifiedbelow, is fulfilled;NOTE The cell(s) that triggers the event is on the frequency indicated in the associated measObject which may be different from the (primary) frequency used by the PCell.Inequality A3-1 (Entering condition)++>+Mn++-OcnOfpOcpMpHysOffOfnInequality A3-2 (Leaving condition)++<Mn++++MpOcpOfnOfpOffHysOcnThe variables in the formula are defined as follows:Mn is the measurement result of the neighbouring cell, not taking into account any offsets.Ofn is the frequency specific offset of the frequency of the neighbour cell (i.e. offsetFreq as defined within measObjectEUTRA corresponding to the frequency of the neighbour cell).Ocn is the cell specific offset of the neighbour cell (i.e. cellIndividualOffset as defined within measObjectEUTRA corresponding to the frequency of the neighbour cell), and set to zero if not configured for the neighbour cell.Mp is the measurement result of the PCell, not taking into account any offsets.Ofp is the frequency specific offset of the primary frequency (i.e. offsetFreq as defined within measObjectEUTRA corresponding to the primary frequency).Ocp is the cell specific offset of the PCell (i.e. cellIndividualOffset as defined within measObjectEUTRA corresponding to the primary frequency), and is set to zero if not configured for the PCell.Hys is the hysteresis parameter for this event (i.e. hysteresis as defined within reportConfigEUTRA for this event).Off is the offset parameter for this event (i.e. a3-Offset as defined within reportConfigEUTRA for this event).Mn, Mp are expressed in dBm in case of RSRP, or in dB in case of RSRQ.Ofn, Ocn, Ofp, Ocp, Hys, Off are expressed in dB.4.4 A4事件定义Event A4 (Neighbour becomes better than threshold)The UE shall:1> consider the entering condition for this event to be satisfied when condition A4-1, as specifiedbelow, is fulfilled;1> consider the leaving condition for this event to be satisfied when condition A4-2, as specifiedbelow, is fulfilled;Inequality A4-1 (Entering condition)-+Mn>+HysThreshOcnOfnInequality A4-2 (Leaving condition)Mn<+++ThreshOfnHysOcnThe variables in the formula are defined as follows:Mn is the measurement result of the neighbouring cell, not taking into account any offsets.Ofn is the frequency specific offset of the frequency of the neighbour cell (i.e. offsetFreq as defined within measObjectEUTRA corresponding to the frequency of the neighbour cell).Ocn is the cell specific offset of the neighbour cell (i.e. cellIndividualOffset as defined within measObjectEUTRA corresponding to the frequency of the neighbour cell), and set to zero if not configured for the neighbour cell.Hys is the hysteresis parameter for this event (i.e. hysteresis as defined within reportConfigEUTRA for this event).Thresh is the threshold parameter for this event (i.e. a4-Threshold as defined within reportConfigEUTRA for this event).Mn is expressed in dBm in case of RSRP, or in dB in case of RSRQ.Ofn, Ocn, Hys are expressed in dB.Thresh is expressed in the same unit as Mn.4.5 A5事件定义Event A5 (PCell becomes worse than threshold1 and neighbour becomes better than threshold2)The UE shall:1> consider the entering condition for this event to be satisfied when both condition A5-1 andcondition A5-2, as specified below, are fulfilled;1> consider the leaving condition for this event to be satisfied when condition A5-3 or condition A5-4, i.e. at least one of the two, as specified below, is fulfilled;NOTE: The cell(s) that triggers the event is on the frequency indicated in the associatedmeasObject which may be different from the (primary) frequency used by the PCell.Inequality A5-1 (Entering condition 1)1Thresh Hys Mp <+Inequality A5-2 (Entering condition 2)2Thresh Hys Ocn Ofn Mn >-++Inequality A5-3 (Leaving condition 1)1Thresh Hys Mp >-Inequality A5-4 (Leaving condition 2)2Thresh Hys Ocn Ofn Mn <+++The variables in the formula are defined as follows:Mp is the measurement result of the PCell, not taking into account any offsets.Mn is the measurement result of the neighbouring cell, not taking into account any offsets.Ofn is the frequency specific offset of the frequency of the neighbour cell (i.e. offsetFreq as defined within measObjectEUTRA corresponding to the frequency of the neighbour cell).Ocn is the cell specific offset of the neighbour cell (i.e. cellIndividualOffset as defined within measObjectEUTRA corresponding to the frequency of the neighbour cell), and set to zero if not configured for the neighbour cell.Hys is the hysteresis parameter for this event (i.e. hysteresis as defined within reportConfigEUTRA for this event).Thresh1 is the threshold parameter for this event (i.e. a5-Threshold1 as defined within reportConfigEUTRA for this event).Thresh2 is the threshold parameter for this event (i.e. a5-Threshold2 as defined within reportConfigEUTRA for this event).Mn, Mp are expressed in dBm in case of RSRP, or in dB in case of RSRQ.Ofn, Ocn, Hys are expressed in dB.Thresh1 is expressed in the same unit as Mp .Thresh2 is expressed in the same unit as Mn .Event A6 (Neighbour becomes offset better than SCell)The UE shall:1> consider the entering condition for this event to be satisfied when condition A6-1, as specifiedbelow, is fulfilled;1> consider the leaving condition for this event to be satisfied when condition A6-2, as specifiedbelow, is fulfilled;1> for this measurement, consider the (secondary) cell that is configured on the frequency indicatedin the associated measObjectEUTRA to be the serving cell;NOTE: The neighbour(s) is on the same frequency as the SCell i.e. both are on the frequency indicated in the associated measObject.Inequality A6-1 (Entering condition)+>Mn++-MsOcsOffHysOcnInequality A6-2 (Leaving condition)+<+Mn++OcsOffMsHysOcnThe variables in the formula are defined as follows:Mn is the measurement result of the neighbouring cell, not taking into account any offsets.Ocn is the cell specific offset of the neighbour cell (i.e. cellIndividualOffset as defined within measObjectEUTRA corresponding to the frequency of the neighbour cell), and set to zero if not configured for the neighbour cell.Ms is the measurement result of the serving cell, not taking into account any offsets.Ocs is the cell specific offset of the serving cell (i.e. cellIndividualOffset as defined within measObjectEUTRA corresponding to the serving frequency), and is set to zero if not configured for the serving cell.Hys is the hysteresis parameter for this event (i.e. hysteresis as defined within reportConfigEUTRA for this event).Off is the offset parameter for this event (i.e. a6-Offset as defined within reportConfigEUTRA for this event).Mn, Ms are expressed in dBm in case of RSRP, or in dB in case of RSRQ.Ocn, Ocs, Hys, Off are expressed in dB.Event B1 (Inter RAT neighbour becomes better than threshold)The UE shall:1> for UTRA and CDMA2000, only trigger the event for cells included in the correspondingmeasurement object;1> consider the entering condition for this event to be satisfied when condition B1-1, as specifiedbelow, is fulfilled;1> consider the leaving condition for this event to be satisfied when condition B1-2, as specifiedbelow, is fulfilled;Inequality B1-1 (Entering condition)Thresh+Mn>-HysOfnInequality B1-2 (Leaving condition)++Mn<ThreshHysOfnThe variables in the formula are defined as follows:Mn is the measurement result of the inter-RAT neighbour cell, not taking into account any offsets.For CDMA 2000 measurement result, pilotStrength is divided by -2.Ofn is the frequency specific offset of the frequency of the inter-RAT neighbour cell (i.e. offsetFreq as defined within the measObject corresponding to the frequency of the neighbour inter-RAT cell).Hys is the hysteresis parameter for this event (i.e. hysteresis as defined withinreportConfigInterRAT for this event).Thresh is the threshold parameter for this event (i.e. b1-Threshold as defined within reportConfigInterRAT for this event). For CDMA2000, b1-Threshold is divided by -2.Mn is expressed in dBm or in dB, depending on the measurement quantity of the inter-RAT neighbour cell.Ofn, Hys are expressed in dB.Thresh is expressed in the same unit as Mn.4.8 B2事件定义Event B2 (PCell becomes worse than threshold1 and inter RAT neighbour becomes better than threshold2)The UE shall:1> for UTRA and CDMA2000, only trigger the event for cells included in the correspondingmeasurement object;1> consider the entering condition for this event to be satisfied when both condition B2-1 andcondition B2-2, as specified below, are fulfilled;1> consider the leaving condition for this event to be satisfied when condition B2-3 or conditionB2-4, i.e. at least one of the two, as specified below, is fulfilled;Inequality B2-1 (Entering condition 1)+HysMp<Thresh1Inequality B2-2 (Entering condition 2)-+Mn>Ofn2ThreshHysInequality B2-3 (Leaving condition 1)Hys-Mp>1ThreshInequality B2-4 (Leaving condition 2)Mn<++OfnHys2ThreshThe variables in the formula are defined as follows:Mp is the measurement result of the PCell, not taking into account any offsets.Mn is the measurement result of the inter-RAT neighbour cell, not taking into account any offsets.For CDMA2000 measurement result, pilotStrength is divided by -2.Ofn is the frequency specific offset of the frequency of the inter-RAT neighbour cell (i.e. offsetFreq as defined within the measObject corresponding to the frequency of the inter-RAT neighbourcell).Hys is the hysteresis parameter for this event (i.e. hysteresis as defined withinreportConfigInterRAT for this event).Thresh1 is the threshold parameter for this event (i.e. b2-Threshold1 as defined within reportConfigInterRAT for this event).Thresh2 is the threshold parameter for this event (i.e. b2-Threshold2 as defined within reportConfigInterRAT for this event). For CDMA2000, b2-Threshold2 is divided by -2.Mp is expressed in dBm in case of RSRP, or in dB in case of RSRQ.Mn is expressed in dBm or dB, depending on the measurement quantity of the inter-RAT neighbour cell.Ofn, Hys are expressed in dB.修正版Thresh1 is expressed in the same unit as Mp. Thresh2 is expressed in the same unit as Mn.。

A1-B2事件 (LTE)

LTE支持的切换事件有A类和B类，其中A类本用作系统内测量，B类被用作系统间测量A1事件：表示服务小区信号质量高于一定门限；A2事件：表示服务小区信号质量低于一定门限；A3事件：表示邻区质量高于服务小区质量，用于同频、异频的基于覆盖的切换；A4事件：表示邻区质量高于一定门限，用于基于负荷的切换，可用于负载均衡；A5事件：表示服务小区质量低于一定门限并且邻区质量高于一定门限，可用于负载均衡; 异系统测量事件：B1事件：邻小区质量高于一定门限，用于测量高优先级的异系统小区；B2事件：服务小区质量低于一定门限，并且邻小区质量高于一定门限，用于相同或较低优先级的异系统小区的测量。

LTE移动性参数(全局)1最小接入电平基本信息参数名称(中文)参数名称(英文)取值范围单位最小接收电平QrxLevMin LTE (-140 (44)3G (-119 (25)2G (-115 (25)dBm缺省值开局建议值配置步长参数类型LTE:-1403G邻区频点:-119 2G邻区频点:-115LTE:-1223G:-1192G:-1152长整型影响范围修改生效方式参数出处适用制式LTE小区2G/3G邻区频点修改立即生效3GPP TS 36.331通用参数功能该参数表示UE在该小区驻留需满足的最小接收电平门限。

该值取值范围是2G/3G接收电平的实际值，对于LTE/3G , 实际的RxlevMin 等于SIB3/SIB6的IE value的两倍，调整步长为2dbm。

对于2G，实际的RxlevMin等于SIB7的 (IE value * 2) 115，调整步长为2dBm当UE测量到的2G/3G电平满足S准则时，UE才可能驻留在该小区。

参数调整影响调整该参数的门限值，会对小区的选择和驻留有所影响。

QrxLevMin如果设置过高，则UE将无法驻留到该小区。

2高优先级重选门限基本信息参数功能当高优先级小区的S值在一定时间内高于该阀值(threshXHigh)后，UE可以重选到该小区。

LTE基本事件汇总表

U E收到Deactivate Eps Bearer Context Request消息后，收到了RRC Con 以下情况表示ERAB正常释放：如果第k条和第k+1条切换A3事件时间小于1s，且之间没有切换命令，统计为一次HOPrepareAttempt。

如果第k条和第k+1条切换A3事件时间小于1s，且之间有切换命令，切换准备尝试次数+1。

据业务成功。

示附着数据业务失败。

基站向UE发送Detach Request消息后，在15秒内收到UE发出的De 后，在15秒内收到基站发出的Detach Accept消息。

p Complete，则触发该事件。

Setup Complete，或者收到RRC Connection Reject，则触发该事件。

ddModList”或“drb-ToAddModifyList”），并且不包含信元“mobilityControlInfo”，表示ERAB建立尝试。

ration Complete消息，并且消息中的信元“RRC-TransactionIdentifier”值与信元“RRC Connection ReconfiguE RABSetupAttempt事件发生后，UE收到RRCConnectionRees 收到RRC Connection Reconfiguration Complete消息。

U E收到Dea uest消息后，收到了RRC Connection Reconfiguration消息，且消息中有信元“drb-ToReleaseList”。

REQUEST消息和MME的DETACH REQUEST消息，也没有向网络侧主动发出DETACH REQUEST消息，但收到了RRCConnecti到UE发出的Detach Accept消息示ERAB建立尝试。

onnection Reconfiguration”信元值相同，则表示ERAB建立成功。

到RRCConnectionReestablishmentRequest消息。

A1-B2事件 (LTE)

LTE支持的切换事件有A类和B类，其中A类本用作系统测量，B类被用作系统间测量A1事件：表示服务小区信号质量高于一定门限；A2事件：表示服务小区信号质量低于一定门限；A3事件：表示邻区质量高于服务小区质量，用于同频、异频的基于覆盖的切换；A4事件：表示邻区质量高于一定门限，用于基于负荷的切换，可用于负载均衡；A5事件：表示服务小区质量低于一定门限并且邻区质量高于一定门限，可用于负载均衡; 异系统测量事件：B1事件：邻小区质量高于一定门限，用于测量高优先级的异系统小区；B2事件：服务小区质量低于一定门限，并且邻小区质量高于一定门限，用于相同或较低优先级的异系统小区的测量。

LTE移动性参数(全局)1最小接入电平基本信息参数名称(中文)参数名称(英文)取值围单位最小接收电平QrxLevMin LTE (-140 (44)3G (-119 (25)2G (-115 (25)dBm缺省值开局建议值配置步长参数类型LTE:-1403G邻区频点:-119 2G邻区频点:-115LTE:-1223G:-1192G:-1152长整型影响围修改生效方式参数出处适用制式LTE小区2G/3G邻区频点修改立即生效3GPP TS 36.331通用参数功能该参数表示UE在该小区驻留需满足的最小接收电平门限。

该值取值围是2G/3G接收电平的实际值，对于LTE/3G , 实际的RxlevMin 等于SIB3/SIB6的IE value的两倍，调整步长为2dbm。

对于2G，实际的RxlevMin等于SIB7的 (IE value * 2) 115，调整步长为2dBm当UE测量到的2G/3G电平满足S准则时，UE才可能驻留在该小区。

参数调整影响调整该参数的门限值，会对小区的选择和驻留有所影响。

QrxLevMin如果设置过高，则UE将无法驻留到该小区。

2高优先级重选门限基本信息参数功能当高优先级小区的S值在一定时间高于该阀值(threshXHigh)后，UE可以重选到该小区。

LTE.TD-SCDMA事件

LTE测量事件主要有下面几种：Event A1、Event A2、Event A3、Event A4、Event A5、Event B1、Event B2。

Event A1 (Serving becomes better than threshold)：表示服务小区信号质量高于一定门限，满足此条件的事件被上报时，eNodeB停止异频/异系统测量；类似于UMTS里面的2F事件；Event A2 (Serving becomes worse than threshold)：表示服务小区信号质量低于一定门限，满足此条件的事件被上报时，eNodeB启动异频/异系统测量；类似于UMTS里面的2D事件；Event A3 (Neighbour becomes offset better than serving)：表示同频邻区质量高于服务小区质量，满足此条件的事件被上报时，源eNodeB启动同频切换请求；Event A4 (Neighbour becomes better than threshold)：表示异频邻区质量高于一定门限量，满足此条件的事件被上报时，源eNodeB启动异频切换请求；Event A5 (Serving becomes worse than threshold1 and neighbour becomes better than threshold2)：表示服务小区质量低于一定门限并且邻区质量高于一定门限；类似于UMTS里的2B事件；Event B1 (Inter RAT neighbour becomes better than threshold)：表示异系统邻区质量高于一定门限，满足此条件事件被上报时，源eNodeB启动异系统切换请求；类似于UMTS里的3C事件；Event B2 (Serving becomes worse than threshold1 and inter RAT neighbour becomes better than threshold2)：表示服务小区质量低于一定门限并且异系统邻区质量高于一定门限，类似于UMTS里进行异系统切换的3A事件。

LTE常用事件详解

CSFBServiceFail
InterRATHOCmd InterRATHOSuc InterRATHOFail InterRATRedirectionReq InterRATRedirectionSuc InterRATRedirectionFail
RandomAccess
随机接入事件
给出的说明并进行相应的操作。具体说明 UE发送Attach Request消息请求附着到数据业务。 UE发送Attach Request消息后，在45秒内发送Attach Complete消息，表示附着数据业务成功。 UE发送Attach Request消息后，在45秒内未发送Attach Complete消息，表示附着数据业务失败。 UE发送Detach Request消息或基站发送Detach Request 消息请求去附着到数据业务。以下情况表示UE去附着数据业务成功： UE向基站发送Detach Request消息后，在15秒内收到基站发出的Detach Accept消息。基站向UE发送Detach Request消息后，在15秒内收到 UE发出的Detach Accept消息。 UE发送RRC Connection Request消息请求建立RRC连接。
MS发出RRC Connection Request，并且2.5s内UE发出RRC Connection Setup Complete，则触发该事件。 MS发出RRC Connection Request，并且2.5s内UE没有发出RRC Connection Setup Complete，或者收到RRC Connection Reject，则触发该事件。如果RRC Connection Reconfiguration消息中包含特定的信元（“drb-ToAddModList”或“drbToAddModifyList”），并且不包含信元“ mobilityControlInfo”，表示ERAB建立尝试。 ERABSetupAttempt事件发生后，UE在1秒内收到RRC Connection Reconfiguration Complete消息，并且消息中的信元“RRC-TransactionIdentifier”值与信元“ RRC Connection Reconfiguration”信元值相同，则表示ERAB建立成功。以下情况表示ERAB建立失败： ERABSetupAttempt事件发生后，1秒内UE没有收到RRC Connection Reconfiguration Complete消息。 ERABSetupAttempt事件发生后，UE收到 RRCConnectionReestablishmentRequest消息。以下情况表示ERAB正常释放： UE收到Deactivate Eps Bearer Context Request消息后，收到了RRC Connection Reconfiguration消息，且消息中有信元“drb-ToReleaseList”。 UE收到Deactivate Eps Bearer Context Request消息后，收到了RRC Connection release消息。 UE收到MME的DETACH REQUEST消息，或者向网络侧主动发出DETACH REQUEST消息后收到RRC release消息

LTE事件汇总表

含义附着尝试附着成功附着失败去附着尝试
去附着成功
RRC（Radio Resource Control）连接建立请求 RRC连接建立成功 RRC连接建立失败 ERAB（Evolved Radio Access Bearer）建立尝试
ERAB建立成功
ERAB建立失败
ERAB正常释放
ERABAbnormalRel
系统收到UE发送的TRACKING AREA UPDATE REQUEST消息则判断一次TA Update Attempt。 UE发送TRACKING AREA UPDATE REQUEST消息后，规定时间内收到TRACKING AREA UPDATE ACCEPT或TRACKING AREA UPDATE Complete消息，则表示LTE TA更新成功。以下情况都表示LTE TA更新失败：
CSFBServiceSuc
CSFBServiceFail
InterRATHOCmd
InterRATHOSuc InterRATHOFail InterRATRedirectionReq InterRATRedirectionSuc InterRATRedirectionFail
LTE到GSM小区重选事件 LTE到WCDMA小区重选事件 GSM到LTE小区重选事件 WCDMA到LTE小区重选事件 CSFB服务请求
TAUpdateFail
同频切换失败
TA更新请求 TA更新成功
TA更新失败
TAUpdateFail
TA更新失败
Data Transfer Start Data Transfer End Session Start Session End
开始数据传输数据传输结束事件任务开始执行事件任务结束事件

41个常见LTE问题和答案汇总

一、TD-LTE路测中对于掉线的定义如何，掉线率指标是指什么？掉线的定义为测试过程中已经接收到了一定数据的情况下，超过3分钟没有任何数据传输。

掉线率=各制式掉线次数总和/(成功次数+各制式掉线次数总和)二、LTE的测量事件有哪些？同系统测量事件：A1事件：表示服务小区信号质量高于一定门限；A2事件：表示服务小区信号质量低于一定门限；A3事件：表示邻区质量高于服务小区质量，用于同频、异频的基于覆盖的切换；A4事件：表示邻区质量高于一定门限，用于基于负荷的切换，可用于负载均衡；A5事件：表示服务小区质量低于一定门限并且邻区质量高于一定门限，可用于负载均衡;异系统测量事件：B1事件：邻小区质量高于一定门限，用于测量高优先级的异系统小区；B2事件：服务小区质量低于一定门限，并且邻小区质量高于一定门限，用于相同或较低优先级的异系统小区的测量。

三、UE在什么情况下听SIB1消息？SIB1的周期是80ms，触发UE接收SIB1有两种方式，一种方式是每周期接收一次，另一种是UE收到paging消息，由paging消息所含的参数得知系统信息有变化，然后接收SIB1，SIB1消息会通知UE是否继续接收其他SIB。

四、随机接入通常发生在哪5 种情况中？a)从RRC_IDLE 状态下初始接入。

b)RRC 连接重建的过程。

c)切换。

d)RRC_CONNECTED 状态下有下行数据自EPC（核心网）来需要随机接入时。

e)RRC_CONNECTED 状态下有上行数据至EPC 而需要随机接入时。

五、LTE上行为什么要采用SC-FDMA技术？考虑到多载波带来的高PAPR（峰值平均功率比）会影响终端的射频成本和电池寿命。

最终3GPP决定在上行采用单载波频分复用技术SC-FDMA中的频域实现方式DFT-S-OFDM。

可以看出与OFDM不同的是在调制之前先进行了DFT（离散傅里叶变换）的转换，这样最终发射的时域信号会大大减小PAPR。

LTE切换事件介绍

2014年12月15测量测量控制测量的执行与结果的处理处理报告由ue完成判决已测量为基础资源申请与分配主要有网络侧完成执行信令过程支持失败回退测量控制更新切换三步曲切换流程图a1事件
LTE切换事件介绍
吴振青 2014年12月15
切换三步曲
测量
测量控制
测量的执行与结果的处理

处理报告
其中： Ms: 服务小区测量结果 Mn: 异系统邻小区测量结果 Ofn：邻小区频率特定的偏差，默认为0 Hys(b2)：B2事件迟滞参数 Thersh1: B2事件门限1 Thersh2: B2事件门限2
Thank You !
A2事件的切换参数配置
A2事件触发条件：Ms + Hys(2) < Thersh(2) A2事件取消条件：Ms – Hys(1) > Thersh(1）其中：
Ms:服务小区RSRP测量结果 Hys(1)：A1事件迟滞参数 Hys(2)：A2事件迟滞参数 Thersh（1）:A1事件门限参数 Thersh（2）:A2事件门限参数
根据A1事件触发条件：Ms – Hys(1) > Thersh(1）可以算出： Ms>-86时关闭异频测量。
根据A2事件触发条件：Ms + Hys(2) < Thersh(2) 可以算出： Ms<-92时开启异频测量
则当UE测量到的A小区RSRP值为红色区域时，UE不进行异频测量；当 UE测量到的A小区RSRP值为绿色区域时，UE进行异频测量；当UE测量到的A 小区RSRP值为黄色区域时，UE是否进行异频测量取决于UE之前的状态，即 UE的测量状态并不改变。
B1事件判决公式：触发条件： Mn + Ofn - Hys(b1) > Thersh(b1) 取消条件：Mn + Ofn + Hys(b1) > Thersh(b1)

LTE路测问题分析归纳汇总

LTE路测问题分析归纳汇总一、Probe测试需要重点关注参数无线参数介绍➢PCC:表示主载波，SCC：表示辅载波，目前LTE(R9版本)都采用单载波的，到4G（R10版本）有多载波联合技术就表示辅载波。

➢PCI:物理小区标示，范围（0-503）共计504个。

➢RSRP：参考信号接收电平，基站的发射功率，范围：-55 < RSRP <-75dbm。

➢RSSQ：参考信号接收质量，是RSRP和RSSI的比值，当然因为两者测量所基于的带宽可能不同，会用一个系数来调RSRQ=N*RSRP/RSSI。

➢RSSI：接收信号强度指示，表示UE所接收到所有信号的叠加。

➢SINR：信噪比，是接收到的有用信号的强度与接收到的干扰信号（噪声和干扰）的强度的比值，Average SINR>20➢Transmission mode:传送模式，一共有8种，TM1表示单天线传送数据，TM2表示传输分集（2个天线传送相同的数据，在无线环境差（RSRP和SINR差）情况下，适合在边缘地带），TM3表示开环空间复用（2个天线传送不同的数据，速率可以提升1倍），TM4表示闭环环空间复用，TM5表示多用户 mimo,TM6表示rank=1的闭环预编码，TM7表示使用单天线口（单流BF），TM8表示双流BF。

Transmission mode=TM3。

➢Rank Indicator：表示层的意思，rank1表示单层，速率低，rank2表示2层，速率高。

Rank Indicator = Rank 2➢PDSCH RB number：表示该用户使用的RB数。

这个值看出，该扇区下大概有几个用户。

（20M带宽对应100个RB，15M带宽对应75个RB,10M带宽对应50个RB,5M带宽对应25个RB，3M带宽对应15个RB，1.4M带宽对应6个RB）多用户可以造成速率低原因之一。

➢PDCCH DL Grant Count：下行时域（子帧）调度数，PDCCH DL Grant Count >950。

LTE测量事件

LTE测量事件Measurement report triggering（3GPP）Ms：服务小区测量结果Mn：邻小区测量结果Mp：主小区测量结果Ofn：邻小区特定频率偏置Ocn：邻小区小区特定偏置Ofp：主小区特定频率偏置Ocp：邻小区小区特定偏置Off：事件偏置Hys：事件迟滞参数Thresh：事件门限Mcr：参考信号测量结果Ocr：参考信号偏置Mref：参考信号参考值Oref：参考信号参考偏置Event A1 (Serving becomes better than threshold)服务小区高于一定门限触发条件：Ms -Hys > Thresh离开条件：Ms + Hys < ThreshEvent A2 (Serving becomes worse than threshold)服务小区低于一定门限触发条件：Ms + Hys < Thresh离开条件：Ms -Hys > ThreshEvent A3 (Neighbour becomes offset better than PCell/ PSCell)邻小区高于主小区触发条件：Mn+Ofn+Ocn-Hys > Mp +Ofp +Ocp +Off离开条件：Mn+Ofn+Ocn+ Hys < Mp +Ofp +Ocp +OffEvent A4 (Neighbour becomes better than threshold)邻小区高于一定门限触发条件：Mn+Ofn+Ocn-Hys > Thresh ；离开条件：Mn+Ofn+Ocn+ Hys < ThreshEvent A5 (PCell/ PSCell becomes worse than threshold1 and neighbor becomes better than threshold2)主小区低于一定门限，邻小区高于一定门限触发条件1：Mp+ Hys < Thresh1 ，触发条件2：Mn+Ofn+Ocn-Hys > Thresh2离开条件1：Mp-Hys > Thresh1 ，离开条件2：Mn+Ofn+Ocn+ Hys < Thresh2Event A6 (Neighbour becomes offset better than SCell)邻小区高于辅小区触发条件：Mn + Ocn - Hys > Ms +Ocs +Off离开条件：Mn + Ocn + Hys < Ms +Ocs +OffEvent B1 (Inter RAT neighbour becomes better than threshold)异系统邻小区高于一定门限触发条件：Mn +Ofn ? Hys > Thresh离开条件：Mn+Ofn+ Hys < ThreshEvent B2 (PCell becomes worse than threshold1 and inter RAT neighbourbecomes better than threshold2)主小区低于一定门限，异系统邻小区高于一定门限触发条件1：Mp+ Hys < Thresh1 ，触发条件2：Mn+Ofn?Hys > Thresh2离开条件1：Mp- Hys > Thresh1 ，离开条件2：Mn+Ofn+ Hys < Thresh2Event C1 (CSI-RS resource becomes better than threshold)参考信号信道质量指示高于一定门限触发条件：Mcr +Ocr -Hys > Thresh离开条件：Mcr +Ocr + Hys < ThreshEvent C2 (CSI-RS resource becomes offset better than reference CSI-RS resource)参考信号信道质量指示高于参考信号质量指示参考值触发条件：Mcr +Ocr - Hys > Mref +Oref +Off离开条件：Mcr +Ocr + Hys < Mref +Oref +Off。