CDMA無線網(wǎng)絡(luò)優(yōu)化方法探討及案例分析


目錄
中文摘要 I
ABSTRACT II
1　引言 1
1.1　課題背景 1
1.1.1　移動通信行業(yè)發(fā)展 1
1.1.2　CDMA技術(shù)的發(fā)展現(xiàn)狀 1
1.2　本課題研究的目的和意義 2
1.3　本課題研究的主要內(nèi)容 3
2　基本原理 4
2.1　CDMA基本概念 4
2.2　DS-CDMA的關(guān)鍵技術(shù) 4
2.2.1　功率控制技術(shù) 4
2.2.2　PN碼技術(shù) 5
2.2.3　RAKE接收技術(shù) 5
2.2.4　軟切換(Soft Handoff)技術(shù) 5
2.3　CDMA網(wǎng)基本結(jié)構(gòu)系統(tǒng) 7
3　CDMA無線網(wǎng)絡(luò)優(yōu)化流程和方法 8
3.1　CDMA無線網(wǎng)絡(luò)優(yōu)化概述 8
3.2　CDMA無線網(wǎng)絡(luò)優(yōu)化的發(fā)展 8
3.3　CDMA無線網(wǎng)絡(luò)優(yōu)化的分類 9
3.3.1　工程優(yōu)化 9
3.3.2　運(yùn)維優(yōu)化 10
3.4　CDMA無線網(wǎng)絡(luò)優(yōu)化的通常流程 10
3.5　CDMA無線網(wǎng)絡(luò)優(yōu)化的方法 12
3.6　CDMA無線網(wǎng)絡(luò)優(yōu)化的主要內(nèi)容 13
3.6.1　優(yōu)化準(zhǔn)備工作 13
3.6.2　現(xiàn)場測試 14
3.6.3　CLUSTER級的調(diào)整和優(yōu)化 14
3.6.4　系統(tǒng)級優(yōu)化（有負(fù)載） 15
4　CDMA網(wǎng)絡(luò)優(yōu)化典型案例分析 16
4.1　CDMA無線掉話常見原因分析及優(yōu)化 16
4.1.1　處干覆蓋范圍以外的掉話 16
4.1.2　導(dǎo)頻污染引起的掉話 18
4.1.3　前反向鏈路不平衡引起的掉話 19
4.1.4　干擾引起的掉話 20
4.2　CDMA網(wǎng)絡(luò)中切換問題 21
4.2.1　硬切換 21
4.2.2　軟切換及更軟切換 22
4.2.3　典型案例分析 25
4.3　總結(jié) 28
5　結(jié)束語 29
致謝 30
參考文獻(xiàn) 31

 
中文摘要
CDMA是為滿足現(xiàn)代移動通信網(wǎng)在大容量、高質(zhì)量、綜合業(yè)務(wù)、軟切換、國際漫游等方面的要求而設(shè)計(jì)的一種先進(jìn)移動通信技術(shù)，它具有抗干擾性好，抗多徑衰落，保密安全性高等諸多優(yōu)點(diǎn)。CDMA網(wǎng)絡(luò)是中國電信的主推品牌，CDMA2000 (3G)業(yè)務(wù)的發(fā)展直接影響到中國電信的成敗，而CDMA業(yè)務(wù)的發(fā)展必須依賴完善的網(wǎng)絡(luò)才能順利進(jìn)行。因此，CDMA系統(tǒng)在運(yùn)營過程中需要不斷地進(jìn)行網(wǎng)絡(luò)優(yōu)化，一是為了能夠給系統(tǒng)當(dāng)前的用戶提供更加優(yōu)質(zhì)的服務(wù)，二是為了提高系統(tǒng)容量，以接納越來越多的系統(tǒng)未來用戶。
本文的研究目標(biāo)是對投入運(yùn)行的網(wǎng)絡(luò)進(jìn)行參數(shù)采集、數(shù)據(jù)分析，找出影響網(wǎng)絡(luò)運(yùn)行質(zhì)量的原因，通過技術(shù)手段或參數(shù)調(diào)整使網(wǎng)絡(luò)達(dá)到最佳運(yùn)行狀態(tài)的方法，使網(wǎng)絡(luò)資源獲得最佳效益，同時(shí)了解網(wǎng)絡(luò)的增長趨勢，為擴(kuò)容提供依據(jù)。具體的網(wǎng)絡(luò)優(yōu)化主要包括以下幾方面內(nèi)容: 網(wǎng)絡(luò)覆蓋問題；掉話問題；二次呼叫問題；越區(qū)切換問題；與其他網(wǎng)絡(luò)手機(jī)用戶的互連互通等。
本課題主要研究CDMA無線通信網(wǎng)絡(luò)中掉話和切換問題的分析和優(yōu)化。通過對覆蓋區(qū)基本情況、網(wǎng)絡(luò)覆蓋、質(zhì)量、話務(wù)的分析，應(yīng)用現(xiàn)有理論和技術(shù)，在前期工程的基礎(chǔ)上為完善CDMA網(wǎng)絡(luò)的覆蓋并優(yōu)化網(wǎng)絡(luò)，提出切實(shí)可行的設(shè)計(jì)方案。使得網(wǎng)絡(luò)容量、質(zhì)量、經(jīng)濟(jì)效益、競爭力達(dá)到預(yù)期設(shè)定的目標(biāo)值，最終滿足客戶市場的需求。
關(guān)鍵詞：無線網(wǎng)絡(luò)優(yōu)化、CDMA、掉話問題、軟切換技術(shù)等

ABSTRACT
CDMA is a kind of advanced mobile telecommunication technology, which fulfill great capacity and quality、synthetical operation、soft switch and international ramble. It possesses lots of merits such as repellence of interference and attenuation of multiple paths. The security is also great trait of CDMA. CDMA is the main operation that China Unicorn extend .The progress of CDMA right result in the success of China Unicom，and the development of operation must depend on perfect network. Therefore, in the process of management, it is completely necessary to optimize CDMA wireless network constantly On the one hand, the purpose of optimizing CDMA wireless network is to provide more consummate service, and on the other hand, it is to extend system capacity in order to take up more and more consumers.
The purpose of this task is to investigate the best methods that can optimize CDMA wireless network by collecting data of network which is in operation and analyzing the data in order to find the cause which influences the quality of the network. The advantage of CDMA is application of power control and soft switch, so they are usually the emphases during base station optimizing. On the other hand, data optimizing is also important and difficult. Concretely, methods of optimizing are as following: l、the issue of network coverage 2、dropped calls problem 3、the second call issues 4、handoff issues 5、with other network users, such as the interconnection.
The main research topics of CDMA wireless communications network are dropped calls and switching analysis and optimization. Covered by the basic situation of the district, network coverage quality and traffic analysis. Applying of existing theory and technology, the basis of pre-engineering to improve the coverage of CDMA networks and optimized networks is practical designed. Makes network capacity, quality, cost-effective, competitive edge to achieve the desired target set, and ultimately meet customer needs of the market.
Keywords: wireless network optimization, CDMA, the issue of dropped calls, soft switching technology