LTE系统内测量事件

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.。

LTE测量与切换详解（非常全面）1 测量过程测量过程主要包括以下三个步骤：测量配置：由eNB通过RRCConnectionReconfigurtion消息携带的measConfig信元将测量配置消息通知给UE，即下发测量控制。

测量执行：UE会对当前服务小区进行测量，并根据RRCConnectionReconfigurtion消息中的s-Measure信元来判断是否需要执行对相邻小区的测量。

测量报告：测量报告触发方式分为周期性和事件触发。

当满足测量报告条件时，UE将测量结果填入MeasurementReport消息，发送给eNB。

1.1 测量配置测量配置主要由eNB通过RRCConnectionReconfigurtion消息携带的measConfig信元将测量配置消息通知给UE，包含UE需要测量的对象、小区列表、报告方式、测量标识、事件参数等。

当测量条件改变时，eNB通知UE新的测量条件。

●触发条件：eNB向UE发起/修改/删除测量。

●发送网元：（eNB）处理：将测量配置填项填入RRCConnectionReconfigurtion消息中的measConfig信元。

●接收网元（UE）处理：UE侧维护一个测量配置数据库VarMeasConfig，在VarMeasConfig 中，每个measId对应一个measObjectId和一个reportConfigId。

其中，measId是数据库测量配置条目索引；measObjectId是测量对象标识，对应一个测量对象配置项；reportConfigId是测量报告标识，对应一个测量报告配置项。

此外还包含了与measId无关的公共配置项quantityConfig、测量量配置、s-Measure和服务小区质量门限控制等。

Measurement objects（测量对象）：UE测量的对象如下●对于频率内和频率间的测量，测量对象是一个单一的E-UTRA承载频率。

LTE重要术语PCI：LTE是用PCI（Physical Cell ID）来区分小区，并不是以扰码来区分小区，LTE无扰码的概念，LTE共有504个PCI。

PCI由PSS（0-2），SSS（0-167）组成。

RSRP (Reference Signal Receiving Power，参考信号接收功率) 是LTE网络中可以代表无线信号强度的关键参数以及物理层测量需求之一，是在某个符号内承载参考信号的所有RE(资源粒子)上接收到的信号功率的平均值。

RSRQ（ReferenceSignalReceivingQuality）表示L TE参考信号接收质量，这种度量主要是根据信号质量来对不同LTE候选小区进行排序。

这种测量用作切换和小区重选决定的输入。

RSRQ被定义为N*RSRP/(LTE载波RSSI）之比，其中N 是LTE载波RSSI测量带宽的资源块（RB）个数。

RSRQ实现了一种有效的方式报告信号强度和干扰相结合的效果。

SINR：信号与干扰加噪声比（Signal to Interference plus Noise Ratio）是指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；可以简单的理解为“信噪比”。

RSSI：载波接收信号强度指示。

UE对所有信号来源观测到的总接收带宽功率。

2、天线重点天线增益一般常用dBd和dBi两种单位。

dBi用于表示天线在最大辐射方向场强相对于全向辐射器的参考值；而相对于半波振子的天线增益用dBd表示：dB：仅仅是个相对值，dB＝10log（P1/P2），比如A基站的发射功率是600mw，B基站是300mw，那么A基站比B基站发射功率高10lg（600/300）＝3 dB，从公式中可以看出dB是表征两个功率的相对值，是没有单位的。

dB是一个无单位的量纲。

dBm：是一个考证功率绝对值的值，公式为dBm=10lg(功率/1mW)，如我们常用的基站是500mw，换算成dBm就是10lg(500mW/1mW)＝27dBm（意思是27dB毫瓦）。

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。

一、单选题1、中国移动2013年开始大规模部署的4G网络属于哪种制式（A）A. TD-LTEB. LTE-FDDC. WCDMAD. GSM2、Nanocell是（A）提出的。

A. 中国移动B. 中国联通C. 中国电信D. 中国广电3、中国移动2013年4G网络工程无线建设频率规划（C）A. F和E用于室外，D用于室内B. F和A用于室外，E用于室内C. F和D用于室外，E用于室内D. F和D用于室外，A用于室内4、中国移动香港公司在香港部署的LTE网络制式（C）A. TD-LTEB. LTE FDDC. 双模，先部署LTE FDD，后TD-LTED. 双模，先部署TD-LTE，后LTE FDD5、简单地说，CSFB方案的本质是什么（C）A. 在LTE网络下，利用VOIP承载语音B. 在LTE网络下，利用OTT（如微信）承载语音C. 在LTE网络下，回落到2G/3G网络，利用2G/3G网络承载语音6、以下哪个不属于TD-LTE网络使用的无线频段（D）A. F频段B. D频段C. E频段D. A频段7、TD-LTE网络在发展用户时最可能采用的策略是（A）A. 要换卡、不登记、不换号B. 不换卡、不登记、不换号C. 要换卡、要登记、要换号D. 不换卡、要登记、要换号8、TD-LTE技术能够提供的理论最高下载速率在什么速率级别（A）A. 百兆比特/每秒B. 兆比特/每秒C. 比特/每秒D. 吉比特/每秒9、使用TD-LTE的手机终端用户可以使用（C）A. 只有数据业务B. 只有语音业务C. 数据、语音皆可10、相对于3G，LTE取消了哪个网元（B）A. NodeBB. RNCC. HSSD. DRA11、以下关于LTE TDD的说法正确的是哪个（B）A. 上行时隙转下行时隙需要一个特殊时隙做保护间隔B. 下行时隙转上行时隙需要一个特殊时隙做保护间隔C. 两种情况都不需要特殊时隙做保护间隔D. 两种情况都需要特殊时隙做保护间隔12、LTE系统一共有（D）组SSS序列A. 3B. 12C. 128D.16813、以下哪个信道用于寻呼和用户数据的资源分配（B）A. PDSCHB. PDCCHC. PBCHD. PCFICH14、以下对于LTE功率控制描述正确的是（D）A. 功率控制通过调整发射功率，使业务质量刚好满足BLER(Block Error Rate)要求，避免功率浪费B. LTE干扰主要来自同频邻区，功率控制可减小对邻区的干扰C. 上行功率控制可以有效减少UE 电源消耗D. 以上都正确15、下列哪个说法是错误的（D）A. CSFB方案不需要部署IMSB. CSFB需要支持SGs接口C. VoLTE/SRVCC实现了IMS至CS域的语音连续性D. eSRVCC的语音质量更高16、E-UTRA系统覆盖半径最大可达（D）A. 10kmB. 30kmC. 50kmD. 100km17、对于TD-LTE，一个无线帧时间长度（D）A. 0.5msB. 1msC. 5msD. 10ms18、PDSCH不支持下列哪种调制方式（A）A. BPSKB. QPSKC. 16QAMD. 64QAM19、以下哪个属于ICIC的干扰抑制技术（D）A. 加扰B. 交织C. 波束赋形D. 静态小区间干扰协调20、LTE系统子载波带宽为（C）KHzA. 5KHzB. 10KHzC. 15KHzD. 20KHz二、多选题1、TD-LTE终端形态包括（ABCD）A. 手机B. 数据卡C. MiFiD. CPE2、中国移动2013年4G网络工程无线建设无线基站建设方式主要包括（ABCD）A. F频段新建B. F升级C. D频段新建D. E频段新建3、以下不属于多址技术的包括（BD）A. TDMAB. FDDC. CDMAD. TDDE. OFDMA4、TD-LTE-Advanced系统的关键技术包括（ABD）A. 载波聚合技术B. 中继技术C. 智能检测技术D. 多点协作技术5、与3G相比，下列关于LTE说法正确的是哪些（ABCD）A. LTE节点更少B. LTE信令更少C. LTE小区边缘数据速率更高D. LTE有较高的频谱灵活性6、关于MIMO，以下说法正确的是（ABCD）A. 空间复用可以提升小区吞吐率和峰值速率B. 空间复用在小区中心区域C. 上行使用虚拟MIMOD. 空间分集可以增加覆盖和吞吐率7、TDD与FDD的差别（AC）A. 双工模式差异：FDD、TDD双工方式不同B. 多址方式差异：FDD、TDD多址方式不同C. 帧结构差异：FDD、TDD帧结构不同D. 带宽差异：FDD、TDD支持的带宽不同8、关于LTE网络整体结构，哪些说法是正确的（ABC）A. E-UTRAN用E-NodeB替代原有的RNC-NodeB结构B. 各网络节点之间的接口使用IP传输C. 通过IMS承载综合业务D. E-NodeB间的接口为S1接口9、LTE系统中的UE的RRC状态包括（AC）A. RRC空闲态B. RRC繁忙态C. RRC连接态D. RRC掉线态10、LTE中，下列哪项是Primary SCH的作用（ABD）A. OFDM符号定时B. 频率同步C. cell I D group号的检测D. 所属cell ID group中的三种cell id的检测11、LTE系统中一个RB对应时间和频率资源分别是多少（BD）A. 1msB. 0.5msC. 6个子载波D. 12个子载波12、LTE下行调度器可以处理的资源有（ACD）A. 物理资源块B. 下行功率C. PDCCH资源D. 信号发射的秩13、LTE系统中下行参考信号的主要目的是（AB）A. 下行信道质量测量，又称为信道探测B. 下行信道估计，用于UE端的相干检测和解调C. 小区搜索D. 时间和频率同步14、LTE功率控制的类型包括（ABCD）A. 开环功控B. 闭环功控C. 内环功控D. 外环功控15、LTE中CP的作用是（AB）A. 避免符号间干扰B. 维持正交性C. 避免载波间干扰D. 决定小区的覆盖范围16、以中的资源调度包含的是移动性管理流程（ABC）A. TA更新B. 分离C. 附着D. 业务请求17、LTE空中接口协议栈控制面部分包括（ABCDE）A. PHYB. MACC. RLCD. PDCPE. RRC18、以下哪些方法可以用来解决越区覆盖问题（AD）A. 适当降低越区小区的发射功率B. 调整越区小区上行功控参数C. 调整越区小区下行调度方式D. 调整越区小区天线参数（高度，倾角，方位角等）E. 调整越区小区及其周边小区的切换门限参数19、LTE中的资源调度包含的维度有（ABC）A. 时域B. 频域C. 空域D. 码域20、以下物理信道描述正确的有（ACE）A. PDSCH：物理下行共享信道B. PMCH：物理广播信道C. PDCCH：物理下行控制信道D. PBCH：物理多播信道E. PCFICH：物理控制格式指示信道三、填空题1、无线通信系统主要由发射机、接收机和天线三大部分组成。

LTE系统事件介绍一、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- 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 withinreportConfigEUTRA 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 withinreportConfigEUTRA 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 withinreportConfigEUTRA 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 conditionA5-4, 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 associated measObject which may be different from the (primary) frequency used by the PCell.Inequality A5-1 (Entering condition 1)+Mp<HysThresh1Inequality A5-2 (Entering condition 2)+-+Mn>Thresh2HysOcnOfnInequality A5-3 (Leaving condition 1)-Mp>HysThresh1Inequality A5-4 (Leaving condition 2)2++Mn<+OfnHysThreshOcnThe 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 withinreportConfigEUTRA 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.Thresh1is expressed in the same unit as Mp.Thresh2is 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.Thresh1is expressed in the same unit as Mp.Thresh2is expressed in the same unit as Mn.第11页。

一、L T E切换事件系统内测量事件采用Ax来标识，系统内事件的报告各类：●eventA1：服务小区质量高于一个绝对门限（serving>threshold）。

用于关闭正在进行的频间测量，在RRC控制下去掉激活测量间隙（gap）事件进入条件：Ms-Hys>Thresh事件离开条件：Ms+Hys<Thresh其中Ms：为服务小区的测量结果，没有计算任何小区各自的偏置如果测量的是RSRP则单位为dBm，如果是RSRQ则单位为dB。

Hys：为此事件的滞后参数。

单位为dB。

取值范围（0-30）实际值=取值*0.5dBThresh：为此事件的门限参数。

单位同Ms一样●eventA2：服务小区质量低于一个绝对门限（serving<threshold）。

用于打开频间测量，在RRC控制下激活测量间隙（gap）。

事件进入条件：Ms+Hys<Thresh事件离开条件：Ms-Hys>Thresh●eventA3：邻小区比服务小区质量高于一个门限（Neighbour>Serving+Offset）用于频内/频间的基于覆盖的切换。

●事件进入条件：Mn+Ofn+Ocn-Hys>Ms+Ofs+Ocs+Off●事件离开条件：Mn+Ofn+Ocn+Hys<Ms+Ofs+Ocs+Off●其中●Mn：邻小区的测量结果，不考虑计算任何偏置。

●Ofn：该邻区频率特定的偏置（即offsetFreq在measObjectEUTRA中被定义为对应于邻区的频率）●Ocn：为该邻区的小区特定偏置（即cellIndividualOffset在measObjectEUTRA中被定义为对应于邻区的频率），同时如果没有为邻区配置，则设置为零。

●Ms：为没有计算任何偏置下的服务小区的测量结果。

●Ofs：为服务频率上频率特定的偏置（即offsetFreq在measObjectEUTRA中被定义为对应于服务频率）●Ocs：为服务小区的小区特定偏置（即cellIndividualOffset在measObjectEUTRA中被定义为对应于服务频率），并设置为0，如果没有为服务小区配置的话；●Hys：为该事件的滞后参数（即hysteres为reportConfigEUTRA内为该事件定义的参数）。

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。