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诺基亚异频负载均衡报告1诺基亚北京项目LTE优化组2016年3月诺基亚异频负载均衡报告诺基亚异频负载均衡报告2目录1.背景....................................................................................................................................32.负载均衡功能测试............................................................................................................42.1异厂家负载均衡功能测试....................................................................................42.1.1参数设置.....................................................................................................42.1.2实验效果.....................................................................................................62.2同厂家同站双载波负载均衡功能测试................................................................82.1.3参数设置.....................................................................................................92.1.4实验效果...................................................................................................103.遗留问题.........................................................................................................................13诺基亚异频负载均衡报告31.背景在LTE中，由于小区半径的减少，用户分布不均匀的现象十分严重，经常会出现某个小区负载较重而其邻居负载较低的现象，不仅会降低网络容量而且还会影响到用户的服务质量。上述原因直接促使了负载均衡技术的诞生，在保证用户的服务质量的同时，使网络总容量达到最大化。目前所支持的负载均衡功能如下：iFLB：InterFrequencyLoadBalance异频负载平衡当高负荷小区的负荷超过HighLoad门限后进入iFLB激活状态，并可以触发LB切换，直到小区负荷低于Targetload门限，则退出iFLB激活状态；在iFLB激活状态期间，ENB间的负荷信息不通过X2接口进行交互，所以这种状态下触发的LB切换属于邻区负荷未知的盲切换，只要目标邻区的下行rsrp大于设定的LNHOIF:thresholdRsrpIFLBFilter参数门限就会触发。而当切换请求消息(HandoverRequestCause:ReduceLoadinServingCell)发送给异频的目标邻区时如果邻区负荷已经超过了自己小区设置的TargetLoad门限的话，邻区会拒绝该切换请求。AMLE：ActiveModeLoadEqualization主动模式负载均衡小区开通AMLE功能后，当小区的负荷门限高于HighLoad的时候，小区会触发和异频邻区的负荷信息交换，它通过X2连接获取邻区的CAC信息(即邻区的综合可用容量)，当主小区和异频邻区负荷满足如下条件时触发AMLE的LB切换：•当邻区可用容量与本小区的可用容量差值大于设定参数门限AMLEPR:deltaCac时则触发LB的切换•主小区的可用容量AMLEPR:maxCacThreshold•邻区的可用容量=AMLEPR:cacHeadroom•UE检测到的目标邻区的下行rsrp大于设定的LNHOIF:thresholdRsrpIFLBFilter参数门限iFLB与AMLE的区别：iFLBAMLE当小区达到高负载门限时，iFLB提供负载均衡AMLE将小区与配对邻区的负载差异控制在所设的负载差值以内iFLB的目的是把小区的负载控制在所设的负载门限下，而不是平衡小区间的负载候选邻区的筛选过程类似iFLB负载的信息只在同个eNB的小区间分享；对于不同eNB小区使用的是盲切换，不根据邻区的负载情况来判断小区间使用资源状态报告(RSR)来分享负载情况，不使用盲切换，对于没有RSR的邻区将不会被切换诺基亚异频负载均衡报告42.负载均衡功能测试2.1异厂家负载均衡功能测试为进行Nokia和HWLTE基站间负载均衡的实验，选定实验点为首都机场T1出发厅。如下图所示，涉及到的Nokia小区为朝阳机场T1F2至F3层公共区NLM（ENBID：76309），涉及到的HW基站为顺义首都机场T1航站楼F2F3东侧办公餐饮区及出港大厅HLM499769-132。2.1.1参数设置开启featureLTE1531:Inter-frequencyLoadBalancingExtension（开启iFLB）ParameterNameParameterFullNameMOC默认值修改值03019:06~13：00修改值0226-210:45~11:30修改值0226-110:00~10:30actInterFreqLBActivationofinterfrequencyloadbalancing(iFLB)LNBTSfalseTRUETRUETRUEthresholdRsrpIFLBFilterInter-FrequencyLBThresholdforRSRPTargetFilterLNHOIF-98-95-95-95thresholdRsrqIFLBFilterInter-FrequencyLBThresholdforRSRQTargetFilterLNHOIF-12-12-12-12targetLoadGbrDlDLGBRresourcetargetloadLNCEL50505050诺基亚异频负载均衡报告5targetLoadNonGbrDlDLnon-GBRresourcetargetloadLNCEL75755%8%targetLoadPdcchPDCCHtargetloadLNCEL503%50%5%iFLBHighLoadGBRDLInter-FrequencyLoadBalancingDLGBRHighLoadLNCEL60606060iFLBHighLoadNonGBRDLInter-FrequencyLoadBalancingDLnon-GBRHighLoadLNCEL85858%10%iFLBHighLoadPdcchInter-FreqLoadBalancingPDCCHHighLoadLNCEL805%80%7%nomNumPrbNonGbrNominalnumberofPRBsforloadbalancingLNCEL1101010iFLBBearCheckTimerInter-FrequencyLoadBalancingQCI1BearerCheckTimerLNCEL12121212prohibitLBHOTimerProhibitLoadBasedHandoverTimerLNCEL10101010iFLBRetryTimerInterFreqLoadBalRetryTimerLNCEL60606060开启featureLTE1841:Inter-FrequencyLoadEqualization（开启AMLE）MOClassParameterNameParameterFullName默认值修改值3月1日16:39:00LNBTSactIfHoEnableinterFrequencyhandoverenabledenabledLNBTSactAmleActivateactivemodeloadequalizationfalseTRUELNBTSactInterFreqLBActivationofinterfrequencyloadbalancing(iFLB)falseTRUELNBTSprohibitLBHOTimerProhibitLoadbasedhandovertimer1010LNRELamleAllowedActivemodeloadequalizationallowedfalseTRUELNRELremoveAllowedRemoveallowedtrueFALSELNHOIFthresholdRsrpIFLBFilterInter-freqloadbalthresholdforRSRPtargetfilter-98-95LNHOIFthresholdRsrqIFLBFilterInter-freqloadbalthresholdforRSRQtargetfilter-12不设置LNCELcellResourceSharingModeCellresourcesharingmodenonenoneLNCELthreshold2InterFreqThresholdth2interFreqforRSRP-100-90LNCELthreshold2aThresholdth2aforRSRP-96-87LNCELiFLBRetryTimerInterFreqLoadBalRetryTimer6060sLNCELiFLBHighLoadGBRDLInter-frequencyloadbalancingGBRhighloadDL6060%LNCELiFLBHighLoadNonGBRDLInter-frequencyloadbalancingnon-GBRhighloadDL858%诺基亚异频负载均衡报告6LNCELiFLBHighLoadPdcchInter-frequencyloadbalancingPDCCHhighload8080%LNCELiFLBBearCheckTimerInter-frequencyloadbalancingQCI1Bearerchecktimer1212sLNCELcellCapClassCellcapacityclassvalue100100LNCELtargetLoadGbrDlDLGBRresourcetargetload5050%LNCELtargetLoadNonGbrDlDLnon-GBRresourcetargetload755%LNCELtargetLoadPdcchPDCCHtargetload5050%LNCELmlbEicicOperModeModeforcalculatingtheCACinloadbal.andeICICallUesallUesLNCELnomNumPrbNonGbrNominalnumberofPRBsforloadbalancing110LNCELulStaticCacStaticCACforuplink100100LNCELulCacSelectionUplinkCACsourceselectionulReflectDlCaculReflectDlCacLNCEL-AMLEPRamlePrIdamlePrId0/10LNCEL-AMLEPRdeltaCacDifferenceinCACofsourceandtargetcells205%LNCEL-AMLEPRcacHeadroomHea