诺西网络EGPRS优化手册(V2) - 图文

CSI

DingShijie

GPRS无线优化手册(V2.0)

2015-1-20

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内 容 摘 要

本文基于诺基亚EGPRS网络优化成果和中国地区（E）GPRS项目优化经验，力图能描绘EGPRS网络优化的流程以及具体的优化内容建议，从最为主要的角度来介绍实际优化过程的通

常手段和方法。供后续EGPRS优化项目参考。

CSI

DingShijie

GPRS无线优化手册(V2.0)

2015-1-20 目录

1. 优化手册概述 ............................................................................................................................... 5 2. EGPRS无线网络优化解决方案 .................................................................................................... 5 2.1 优化内容模块和流程............................................................................................................... 5 2.2 EGPRS优化项目人员需求 ..................................................................................................... 6 2.3 EGPRS优化工具需求 ............................................................................................................ 6 3. EGPRS网络配置评估分析 ........................................................................................................... 7 3.1 EGPRS的引入对网络的影响原理 .......................................................................................... 7 3.1.1 TBF平均时间很短的原因 ................................................................................................ 7 3.1.2 GPRS affect to signaling load ......................................................................................... 7 3.1.3 GPRS affect to AGCH..................................................................................................... 8 3.1.4 GPRS affect to PCH ....................................................................................................... 8 3.2 EGPRS/GPRS资源隔离问题的讨论 ...................................................................................... 8 4. 负荷分析和资源分配优化 .............................................................................................................. 8 4.1 无线资源优化常用方法 ........................................................................................................... 8 4.2 EGPRS无线拥塞情况 .......................................................................................................... 11 4.3 EDAP优化 ........................................................................................................................... 14 4.3.1 EDAP设定及检查 ......................................................................................................... 14 4.3.2 EDAP资源优化方法 ...................................................................................................... 15 4.3.3 EDAP优化流程 ............................................................................................................. 16 4.3.4 EGPRS EDAP资源优化效果 ........................................................................................ 17 4.4 PCU优化 ............................................................................................................................. 18 4.4.1 PCU负荷考虑因素-KPI负荷 ......................................................................................... 18 4.4.2 PCU负荷考虑因素-下挂网元 ......................................................................................... 22 4.4.3 PCU内部小区重选带来增益的效果验证 ........................................................................ 22 4.5 Gb优化 ................................................................................................................................ 23 4.6 PAPU的规划合理性分析 ...................................................................................................... 25 5. EGPRS网络参数评估分析 ......................................................................................................... 26 5.1 常规参数 .............................................................................................................................. 26 5.1.1 MBP .............................................................................................................................. 28 5.1.2 CS1,2选择控制参数(DLBH,ULBH,COD,CODH) ........................................................... 29 5.1.3 手机重选控制 参数 .................................................................................................... 29 5.2 PA File中参数的微调 ........................................................................................................... 29 5.2.1 有关TBF定时器的调整 ................................................................................................. 29 5.3 RLC传送控制参数 ............................................................................................................... 31 5.4 无线链路自适应参数优化 ..................................................................................................... 32 5.5 Gb参数优化建议 .................................................................................................................. 35 5.5.1 EGPRS流量控制工作原理 ............................................................................................ 35 5.5.2 EGPRS流量控制测试优化分析 ..................................................................................... 37 5.6 功率控制参数优化 ................................................................................................................ 40 5.7 小区重选参数优化 ................................................................................................................ 41 5.8 HLR参数 ............................................................................................................................. 42 5.9 应用层其它参数 .................................................................................................................... 43 6. EGPRS无线覆盖和质量优化 ...................................................................................................... 43 6.1 现有网络中典型无线环境问题： ........................................................................................... 43 6.2 无线信号问题描述 ................................................................................................................ 43

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DingShijie

7. EGPRS网络性能评估分析 ......................................................................................................... 45 7.1 OSS KPI指标分析 ............................................................................................................... 45 7.2 EGPRS接入性能优化 .......................................................................................................... 46 7.2.1 RACH申请上行TBF的首次接入成功率(Pi_2) .............................................................. 46 7.2.2 GPRS功能吊死小区 ..................................................................................................... 47 7.3 EGPRS时隙分配使用性能 ................................................................................................... 48 7.3.1 上下行时隙请求分配率 .................................................................................................. 48 7.3.2 TBF的重新分配的性能 .................................................................................................. 48 7.3.3 平均GPRS域大小(ava_16) .......................................................................................... 48 7.3.4 上下行TBF掉线率(tbf_28b) .......................................................................................... 48 7.4 EGPRS编码方式性能 .......................................................................................................... 53 7.4.1 CS2编码占用比率 ........................................................................................................ 53 7.5 EGPRS移动管理性能 .......................................................................................................... 53 7.5.1 Ready状态下的小区重选 .............................................................................................. 53 7.5.2 路由区更新 .................................................................................................................... 54 7.6 EGPRS会话管理性能 .......................................................................................................... 54 7.6.1 PDP激活和去激活 ........................................................................................................ 54 8. EGPRS DT/CQT测试和优化 ...................................................................................................... 55 8.1 覆盖率 .................................................................................................................................. 55 8.2 信号主控不佳 ....................................................................................................................... 56 8.3 重选滞后 .............................................................................................................................. 57 8.4 平均C/I ................................................................................................................................ 60 8.4.1 全网C/I统计 ................................................................................................................. 60 8.4.2 C/I分析案例 .................................................................................................................. 60 8.5 信号过覆盖 ........................................................................................................................... 61 8.6 无线时隙不足 ....................................................................................................................... 64 8.6.1 全网统计 ....................................................................................................................... 64 8.6.2 分析案例 ....................................................................................................................... 64 8.7 调制编码方式低 .................................................................................................................... 66 8.8 BLER ................................................................................................................................... 67 8.9 RLC重传率指标定义和优化 ................................................................................................. 68 8.10 FTP速率问题 ................................................................................................................... 69 8.10.1 FTP原理简述 ............................................................................................................ 69 8.10.2 FTP速率慢问题发现 .................................................................................................. 71 8.10.3 FTP速率慢问题分析 .................................................................................................. 72 8.10.4 FTP优化建议及实施情况........................................................................................... 74 8.11 ATTACH时延优化 ............................................................................................................ 75 8.11.1 一步接入和二步接入的影响 ....................................................................................... 75 8.11.2 进一步缩小延时的研究 .............................................................................................. 78 8.11.3 OMC统计验证 ........................................................................................................... 78 8.12 PDP激活时延优化 ............................................................................................................ 79 8.13 路测中较长的空闲时间 ..................................................................................................... 80 8.13.1 Inter/Intra PCU小区重选 .......................................................................................... 81 8.14 Ping时延优化 ................................................................................................................... 83 8.14.1 EGPRS CQT测试试验 .............................................................................................. 83 8.15 Ping失败和WAP登录刷新优化 ....................................................................................... 84 8.15.1 WAP基本流程介绍 .................................................................................................... 84 8.15.2 Ping、WAP登陆和刷新问题类型分析 ....................................................................... 85

GPRS无线优化手册(V2.0)

2015-1-20 3 (97)

CSI

DingShijie

9. EGPRS相关新功能 .................................................................................................................... 88 9.1 NCCR——网络控制小区重选 ............................................................................................... 88 9.2 NACC——Network-Assisted Cell Change ........................................................................... 88 9.3 CS3/CS4 .............................................................................................................................. 89 9.4 DTM——Dual Transfer Mode .............................................................................................. 89 9.5 HMC——High Multislot Classes .......................................................................................... 89 9.6 EDA——Extended Dynamic Allocation ................................................................................ 89 9.7 EPCR ——EGPRS One phase access on CCCH ................................................................ 90 9.8 EUTM ——Extended UL TBF Mode .................................................................................... 90 9.9 Gb over IP介绍 .................................................................................................................... 91 10. 附录： .................................................................................................................................. 91 10.1 休眠小区处理方法 ............................................................................................................. 91 10.2 其他讨论悬疑 .................................................................................................................... 94 10.2.1 无线资源不够造成的TBF建立失败原因主要有： ...................................................... 94 10.2.2 Directed rerty and GPRS. .......................................................................................... 94 10.2.3 GPRS and cell-reselection ........................................................................................ 94 10.2.4 Why do calls always start on CS2? ........................................................................... 95 10.2.5 GPRS and BB hopping .............................................................................................. 96 10.2.6 TRX fault ................................................................................................................... 96 11. 修改历史 .............................................................................................................................. 97

GPRS无线优化手册(V2.0)

2015-1-20

4 (97)