臺灣博碩士論文加值系統

在第三代行動無線通訊系統中，分碼多工( Code Division Multiple Access CDMA )因其抗干擾與高頻譜利用率的特性，成為最具有潛力的無線寬頻通訊技術[1]-[3]。由於CDMA允許多人同時傳輸，在提供多樣化服務的需求下，頻譜資源管理(Radio Resource Management, RRM)成為不可或缺的重要課題。本篇論文的目的在探討具多重服務之分碼多工階層式細胞系統的基地台選取機制。
下一代行動無線通訊系統中，數據服務包含WWW、E-mail、或影像等變成一個主要的服務種類，而其要求較高的頻寬及多樣化服務種類的品質保證要求(QoS)。因此，很難找出一個適合的共用訊務模型來近似各種不同的數據資料。本文想要比較二種大家常用的數據訊務模型，改良型的on-off數據訊務模型和Pareto based的數據訊務模型，進而探討二個不同訊務模型對於系統的影響。
第二，hotspot微細胞(micro cell)通常發生在系統中有某小區域存在較高的負載。雖然用hotspot微細胞台，可以增加系統整体容量和效能，可是由於大細胞和微細胞使用相同的頻帶，使得二個基地台之間會互相干擾。在本文中，我們將研究不同的階層式細胞系統之基地台選取機制，使得階層式細胞系統可以有效的增加容量而不會使得相互間的干擾太過嚴重造成系統效能下降。我們提出一個新的相對pilot訊號強度選取機制。它透過一個保護性質的門檻，使得此機制不只可以保證微細胞能有效的分享hotspot地區的數據負載給大細胞伺服，而且還可以避免微細胞因太過擁擠而達到容量上限，使得hotspot微細胞中的使用者被拒絕。我們將證明我們所提出的機制在階層式細胞系統下可以比大部份的基地台選取機要來得好。

CDMA is one of the most potential techniques in the third generation mobile communication system because of its resistance of interference and high frequency efficiency. Because the CDMA system can serve many users with various services requirements at the same time, radio resource management (RRM) becomes a very important issue. The goal of this thesis is to study cell site selection technique for hierarchical CDMA networks with multi class traffic.
Data services, such as WWW, E-mail and video, etc, will become primary services in the next generation mobile wireless communication system. Theses services require higher bandwidth and diverse QoS requirements. Thus, it is difficult to find a common traffic model that can approximate all kinds of data traffic. This thesis will compare two data traffic models, i.e. a modified on-off data traffic model and Pareto based data traffic model, and evaluate their impacts on the system performance of cellular network.
Secondly, hotspot micro cells often occur in a small area requesting high traffic load. Employing hotspot micro cells can increase system capacity and improve system performance. Because a micro cell and a macro cell use the same frequency band, the system may suffer interference with each other. In this thesis, we investigate different cell site selection algorithms for hierarchical cellular systems to ensure that the system can effectively improve system capacity without suffering severe interference with each other. For this purpose, we propose a new relative pilot based cell site selection algorithm. Through assigning a protection threshold, the relative pilot based cell site algorithm not only can ensure a micro cell to effectively relieve hotspot data traffic load, but avoid the micro cell from serving too much traffic beyond its capability. We will demonstrate that the proposed relative pilot based cell site selection algorithm outperforms most current site selection algorithms in hierarchical CDMA cellular system with multiple traffic classes.

目錄
中文摘要…………………………………………………….…………Ⅰ
英文摘要…….…………………………………………………………Ⅲ
致謝………………………………………………………...…………..Ⅴ
目錄………………………………………………………….…………Ⅵ
表目錄……………………………………………………….…………Ⅹ
圖目錄……………………………………………………….…………Ⅹ
第一章 緒論…………………………………….………………………1
1.1簡介……………………………………………….…………………………1
1.2研究動機和問題描述………………….……………………………………2
1.2.1數據服務的訊務模型……………………………………………………2
1.2.2具多重服務之階層式細胞系統的基地台選取機制……………………3
1.3章節概要………..……………………………...……………………………5
第二章 背景資料………………………….……………………………6
2.1通話允人控制…………………………….…………………………………6
2.2多等級服務……………………………….…………………………………8
2.2.1語音服務訊務模型……..………………………………………………9
2.3 Self Similarity…...…………………………………………………………10
2.4階層式細胞系統………..……………………….…………………………11
2.5 Wrap Around 技巧...………………………………………………………13
第三章 數據訊務模型對蜂巢系統的影響 …………….……………15
3.1 簡介……..…………………………………………………………………15
3.2系統模型…..………………………….……………………………………16
3.2.1數據訊務模型……………………………………….………………16
3.2.1.1改良型的ON-OFF數據訊務模型……………………………16
3.2.1.1 Pareto based的數據訊務模型…………..……………………16
3.2.2系統架構…………………………………………….………………22
3.2.3傳播模型…………………………………………….………………23
3.2.3.1路徑損失模型…………………………………………………23
3.2.3.2 衰減模型…..…………………………………………………23
3.2.4干擾模型…………………………………………….………………23
3.2.5系統效能metric….………………………………….………………24
3.2.5.1模擬比較的參數設定…………………………………………24
3.2.5.2 系統效能的定義………..……………………………………27
3.3理論分析……...……………………………………………………………27
3.3.1blocking機率………..………………………………………………27
3.3.3.1單一細胞…....…………………………………………………27
3.3.3.2多細胞…....……………………………………………………30
3.3.2outage機率…….…….………………………………………………33
3.4系統模擬……………………...……………………………………………34
3.4.1系統規劃……………………...…….………………………………34
3.4.1摸擬結果和討論……………………………………………………36
3.5結論…………………………………...……………………………………42
第四章 具多重服務之階層式細胞系統的基地台選取機制…...……44
4.簡介……………………………………………………………………..……44
4.2基地台選取機制……………………………………………...……………44
4.2.1參考選取機制 (Reference assignment, FA)………..………………45
4.2.2服務導向選取機制 (Service based assignment, SA)………………45
4.2.3服務導向及轉向選取機制 (Service with Transfer based assignment, STA)………………………….……………………………………46
4.2.4 Pilot訊號強度導向選取機制 ( Pilot based assignment, PA )……..47
4.2.5 Pilot訊號強度導向及轉向選取機制 ( Pilot with Transfer based assignment, PTA)……….…………………………………………48
4.2.6對pilot訊號強度導向選取機制(Relative pilot based assignment, RPA)………………………………………………………………49
4.3系統模型………………………...…………………………………………50
4.3.1系統架構和使用者的分布…………………………………………50
4.3.2系統規劃……………………………………………………………51
4.3.3傳播模型……………………………………………………………51
4.3.3.1路徑損失模型…………………………………………………51
4.3.3.2衰減模型…………………...…………………………………52
4.3.4使用者話務量………………………………………………………52
4.3.5功率控制……………………………………………………………53
4.3.6通話允入控演算法…………………………………………………53
4.3.7系統效能的定義……………………………………………………53
4.4系統模擬和討論…..…………………….…………………………………56
4.4.1改良型的ON-OFF數據訊務模型……………………..……………56
4.4.2Pareto based的數據訊務模型……………..……...…………………69
4.6結論………………………………………...………………………………80
第五章 結論和未來研究方向……………….…………………………81
5.1簡介…………………………………………………...……………………81
5.2結論……………………………………………………………...…………81
5.2.1數據訊務模型對蜂巢系統的影響…………………………………81
5.2.2具多重服務之階層式細胞系統的基地台選取機制………………82
5.3未來研究方向………………………………………………………...……82
參考文獻……………………………….………………………………84
附錄…………………………………….………………………………88
表目錄
表3.1Pareto based的數據訊務模型的參數設定 …………….………...…………21
表3.2其他細胞的干擾和自己細胞的干擾的比例關係………...…………………30
表3.3連線預算分析表…….……………………………………..…………………35
表4.1大細胞和微細胞的連線預算分析表…...……………………………………54
圖目錄
圖2.1CDMA系統的CAC運作………………………………………………………8
圖2.2語音服務之訊務模型…..…………………………….………………………10
圖2.3Slowly decaying variance ……………………………….……………………10
圖2.4Long range dependence…………………………………….…………………10
圖2.5階層式細胞系統架構圖…..……………………………….…………………12
圖2.6 Wrap around技巧之細胞模型…..…………………………...………………14
圖3.1改良型的ON-OFF數據訊務模型…..……………………….………………16
圖3.2Pareto based的數據訊務模型………………………………..………………17
圖3.3(a)沒有最大值上限Pareto分佈的PDF……..……………….………….……20
圖3.3(b)有最大值上限Pareto分佈的PDF…………………………………………20
圖3.4蜂巢式架構圖…...……………………………………………………………22
圖3.5(a)單一細胞Blocking Probability的理論分析值和模擬結果……....………29
圖3.5(b)多重細胞Blocking Probability的理論分析值和模擬結果………………32
圖3.6(a)全ON模式下的blocking機率……….……………………………………36
圖3.6(b)全ON模式下的outage機率………………………………………………37
圖3.7(a)ON-OFF的模式的blocking機率………….………………………………39
圖3.7(b)ON-OFF的模式的outage機率……………………………………………39
圖4.1階層式蜂巢架構及使用者分佈示意圖…...…………………………………50
圖4.2(a)數據使用者的blocking機率………………………………………………61
圖4.2(b)數據使用者的outage機率……………...…………………………………62
圖4.3(a)語音使用者的blocking機率…………..……………………..……………60
圖4.3(b)語音使用者的outage機率…………….……………………..……………61
圖4.4(a)數據使用者的cost function:Pb+10Pd………………………..……………66
圖4.4(b)語音使用者的cost function:Pb+10Pd………………………..……………67
圖4.5(a)Pareto based的訊務模型之數據使用者的blocking機率….……..………70
圖4.5(b)Pareto based的訊務模型之數據使用者的outage機率…….……….……71
圖4.6(a)語音使用者的blocking機率 (數據使用者為Pareto based的訊務模型)……...……………………………………………………………………………73
圖4.6(b)語音使用者的outage機率 (數據使用者為Pareto based的訊務模型)……………………………………………………………...……………………74
圖4.7(a) Pareto based的訊務模型之數據使用者的cost function:Pb+10Pd..……77
圖4.6(b)語音使用者的cost function:Pb+10Pd (數據使用者為Pareto based的訊務模型)…………………………………………………………...……………………78

參考文獻
[1]. J. S. Lee , and L. E. Miller, “CDMA Systems Engineering Handbook”, Artech House, pp1012 —1017, 1998.
[2]. H. Holma, and A. Toskala “WCDMA for UMTS — Radio Access For Third Generaion Mobile Communications”, John Wiley & Sons , 2000.
[3]. A. J Viterbi, ”CDMA principles of spread spectrum communication,” Addison Wesley, 1995
[4]. M. Karlsson, ”Admission Control for Packet Data in GSM” (*)
[5]. Y. Ishikawa, and N. Umeda, ”Capacity design and performance of call admission control in cellular CDMA systems,” IEEE JSAC., vol.15, no.: 8, pp.1627 -1635, Oct. 1997.
[6]. S. M. Shin, and C. H. Cho and D. K. Sung, ”Interference-based channel assignment for DS-CDMA cellular systems,” IEEE Trans. on Veh. Technol., vol.48, no. 1, pp.233 -239, Jan. 1999.
[7]. C. Y. Huang, and R. D. Yates, ”Call admission in power controlled CDMA systems,” IEEE 46th Vehicular Technology Conference, vol.3, pp.1665 -1669, 1996.
[8]. Z. Liu, and M. E. Zarki, ” SIR-based call admission control for DS-CDMA cellular systems,” IEEE JSAC., vol.12, no. 4, pp.638 —644, May 1994.
[9]. I. M. Kim, and B. C. Shin, and D. J. Lee, ”SIR-based call admission control by intercell interference prediction for DS-CDMA systems,” IEEE Commun. Lett., vol. 4, no. 1, pp.29 —31, Jan. 2000.
[10]. K. Kim and Y. Han, and C. H. Yim, and K. S. Jeong, ”A call admission algorithm with optimal power allocation for multiple class traffic in CDMA systems,” IEEE VTC. Fall 2000, vol.6, pp.2666 —2671, 2000.
[11]. K. Kim, and Y. Han, ”A call admission control with thresholds for multi-rate traffic in CDMA systems,” IEEE Vehicular Technology Conference Proceedings,. Tokyo, Spring 2000, vol. 2, pp.830 —834, 2000.
[12]. R. F. Chang, and S. W. Wang, ”QOS-based call admission control for integrated voice and data in CDMA system,” IEEE Personal, Indoor and Mobile Radio Commun., PIMRC’6., vol. 2, pp.623 —627, 1996.
[13]. S. Sun, and W. A. Krzymien, ”Call admission policies and capacity analysis of a multi-service CDMA personal communication system with continuous and discontinuous transmission,” IEEE VTC’98, vol. 1, pp.218 -223 vol.1, 1998.
[14]. A. Capone, and S. Redana, ”Call Admission Control Techniques for UMTS,” IEEE Vehicular Technology Conference, VTC Fall 2001, vol. 2, pp.925 —929, 2001.
[15]. N. Dimitriou, G. Sfikas, and R. Tafazolli, ” Call Admission Policies for UMTS,” IEEE VTC’00 Spring, Tokyo, vol.2, pp. 1420 -1424, 2000.
[16]. S. A. Malik, and S. Akhtar, and D. Zeghlache, ”Performance of Prioritized Resource Control for Mixed Services in UMTS WCDMA Networks,” IEEE VTC 2001 Fall, vol. 2, pp.1000 -1004, 2001.
[17]. B. Hjelm, ”Admission control in future multi-service wideband direct-sequence CDMA systems,” IEEE Fall VTC 2000, vo.3, pp.1086 -1093, 2000.
[18]. D. Shen and C. Ji, ”Capability Based Admission Control for Broadband CDMA Networks,” IEEE VTC 2001 Fall, vol. 1, pp.202 -206, 2001.
[19]. M. Meo, and E. Viterbo, ”Performance of wideband CDMA Systems Supporting Multimedia Traffic,” IEEE Communi. Lett., vol. 5, no. 6, pp.251 -253, June 2001.
[20]. “Universal Mobile Telecommunications System(UMTS); “Selection procedures for the choice of radio transmission technologies of the UMTS”, TR 101 112 V3.2.0(1998-04), UMTS 30.03 version 3.2.0, pp.33-37.
[21]. “Mobile Wireless Internet Forum; “ IP in the RAN as a Transport Option in 3rd Generation Mobile Systems Technical Report MTR-006 Release v2.0.0 Ratified June 18, 2001
[22]. E. Anderlind, and J. Zander, ” A traffic model for non-real-time data users in a wireless radio network,” IEEE Communi. Lett., vol. 1, no. 2, pp.37 -39, Mar. 1997.
[23]. J. Shapira, ”Microcell Engineering in CDMA Cellular Networks,” IEEE Trans. Veh. Techno., vol. 43, no. 4 , pp.817 -825, Nov. 1994.
[24]. J. Kim, Y. Han, and J. Ahn, ”An adaptive Traffic Control Scheme for Hierarchically Structured CDMA Cellular System,” IEEE Vehicular Technology Conference, VTC Fall 2000, vol. 5, pp.2192 -2196, 2000.
[25]. J. S. Wu, J. K. Chung, and Y. C. Yang, “Performance Study for a Microcell Hot Spot Embedded in CDMA Macrocell System,” IEEE Trans. Veh. Technol., vol. 48, no. 1, pp. 47 -59, Jan. 1999.
[26]. A. Iera, A. Modafferi, and A. Molinaro, ”Access Control and Hand off Management in Multi-tier Multimedia Wireless System,” IEEE WCNC’99, vol. 3, pp.1518 -1522, 1999.
[27]. A. Iera, A. Modafferi, and A. Molinaro, ”Supporting Multimedia with Soft-QoS Guarantee in Wireless Communication Systems,” IEEE GLOBECOM'99, Vol. 9, pp.69 -73, 1999.
[28]. C. Joh, K. Kim, and Y. Han, ”Performance of a Microcell with Optimal Power Allocation for Multiple Class Traffic in Hierarchically Structured Cellular CDMA System” IEEE Vehicular Technology Conference, VTC 2001 Spring, vol. 4, pp.2818 -2822, 2001.
[29]. 3GPP ,”3rd Generation Partnership Project: Technical Specification Group(TSG) RAN WG4 ‘ Deployment aspects,”3GPP TR 25.922 V5.0.0 (2002-03)
[30]. G. Cimone, D. D. Weerakoon, and A. H. Aghvvami, ”Performance Evaluation of a Two Layer Hierarchical Cellular System with Variable Mobility users Using Multiple Class Applicaiton” IEEE Vehicular Technology Conference, VTC 1999 Fall, vol. 5, pp.2835 -2839, 1999.
[31]. C. Hartmann, and O. Schlegelmilch, ”Hierarchical Cell Structures with Adaptive Radio Resource Management,” IEEE Vehicular Technology Conference, VTC 2000 Fall, vol. 4, pp.1764 -1771, 2000.
[32]. S. Kim, D. Hong and J. Cho, ”Hierarchical Cell Deployment for High Speed Data CDMA Systems,” IEEE WCNC’02, vol. 1, pp.7 -10, Mar. 2000.
[33]. R. Zoican, ”Performance Analysis of a Multiple Traffic Types Microcellular CDMA System,” IEEE Spread Spectrum Techniques and Applications, vol. 1, pp.315 -318, 2000.