伴隨無線通訊技術的快速發展，使用者對於通訊品質和效能的要求也日漸提高，OFDMA通信技術目前是最有可能成為下一代行動通訊系統(4G)的標準。如何降低細胞間干擾(Inter-Cell Interference, ICI)一直是OFDMA中很重要的議題之一。LTE-A新加入的技術CoMP(Coordinate Multi-Point, CoMP)傳送方式主要目的就是解決因為干擾而造成效能低落與傳輸品質不佳的問題。目前LTE眾多的研究論文主要是探討利用頻率重用(Frequency Reuse)機制來解決細胞間干擾問題，但是對於LTE-A的CoMP技術卻是不適合的。本論文提出一個有效率的序列式頻率重用(Sequence Frequency Reuse, SFR)機制改善基於細胞間干擾所引起的效能低落，在不同地區上使用不同的頻率分配使得頻率重用因子更接近1，在細胞間干擾發生最為嚴重的地區做一個頻率重用限制，使之運作於CoMP上更順利同時可降低干擾問題。

The rapid development of the wireless communication technology, has also spurred the rapid growth of the communication quality and efficiency requirements. The OFDMA transmission technology is chosen as candidate standard for the next generation communication system. Method for reducing the Inter-Cell Interference (ICI) is the most important issue in wireless communication systems. Therefore, the new technology for Coordinate Multi-Point (CoMP) transmission in LTE-A is proposed to solve the poor transmission quality and performance problem cause by interference. Recently, a lot of studies proposed to solve ICI by using Frequency Reuse mechanism. However, these studies are not suitable for CoMP in LTE-A. In this thesis, we propose a Sequence Frequency Reuse (SeFR) mechanism to improve throughput of cell-edge users. We use various frequency allocation strategies on different area, such that Frequency Reuse Factor is more close to 1. In seriously interference area, SeFR restrict the frequency reuse to assist CoMP operation and eliminate ICI problem.

目錄
第一章 緒論	1
1-1 研究背景	2
1-2 研究動機	4
1-3 研究目的	5
1-4 論文架構	6
第二章 相關技術研究	7
2-1 LTE & LTE-A	8
2-1-1 LTE	8
2-2-2 LTE-A	10
2-2 典型頻率重用	12
2-2-1 Partial Frequency Reuse	12
2-2-2 Soft Frequency Reuse	13
2-2-3 Incremental Frequency Reuse	15
2-3 Cooperative Frequency Reuse	16
2-3-1 Cell-edge areas partition	16
2-3-2 Frequency reuse rule	17
2-3-3 CCS selection algorithm	20
第三章 序列式頻率重用機制	22
3-1 定義細胞類別	24
3-2 定義細胞邊緣的區域	27
3-3 資源的劃分	31
3-4 根據區域編號使用資源	34
3-4-1 CE在資源使用上的情形	36
3-4-2 CCr在資源使用上的分配使用	43
第四章 模擬比較與分析	51
4-1 實驗環境與參數	51
4-2 模擬結果與比較	54
第五章 結論與未來研究方向	59
5-1 結論	59
5-2 未來研究方向	60
參考文獻	61
附錄-中文論文	66
附錄-英文論文	76

圖目錄
圖2.1 CoMP示意圖	11
圖2.2 頻率資源劃分	12
圖2.3 頻率資源及使用地區	13
圖2.4 頻率資源劃分	13
圖2.5 頻率資源及使用地區	14
圖2.6 頻率劃分	14
圖2.7 IFR頻率資源	15
圖2.8 每個細胞的細胞邊緣分區	17
圖2.9 細胞叢集裡每個細胞的資源分配	18
圖2.10 CoMP在CFR系統的共同傳輸	20
圖3.1 本機制流程圖	23
圖3.2 細胞外觀及實際傳輸範圍	24
圖3.3 細胞型態定義	25
圖3.4 細胞定義流程圖	26
圖3.5 細胞邊緣及細胞中心	27
圖3.6(a) 地帶的分割及編號	28
圖3.6(b) 地帶的由來	28
圖3.7 干擾情形嚴重的細胞角落區域	29
圖3.8 細胞角落	30
圖3.9 定義細胞邊緣流程圖	30
圖3.10 PRB資源劃分方法	32
圖3.11 PRB的資源編號	32
圖3.12 資源使用流程圖	34
圖3.13 資源使用示意圖	35
圖3.14 細胞可使用的資源	36
圖3.15 細胞群集資源使用情形	38
圖3.16 CoMP示意圖(對外)	39
圖3.17 CoMP示意圖(對內)	40
圖3.18 角落資源示意圖	43
圖3.19 細胞角落編號	44
圖3.20 相同頻段資源使用之情形-1	45
圖3.21 相同頻段資源使用之情形-2	46
圖3.22 借用資源示意圖	47
圖3.23 借用機制	48
圖3.24 判斷CCrU無法達到CoMP Transmission	49
圖3.25 歸還資源並對CCrU進行CoMP Transmission	50
圖3.26 判斷及歸還機制	50
圖4.1 使用者均勻分布情況下，使用者的平均吞吐量	55
圖4.2 使用者均勻分布情況下，細胞邊緣的平均吞吐量	56
圖4.3 使用者不均勻分布情況下，使用者的平均吞吐量	57
圖4.4 使用者不均勻分布情況下細胞邊緣的平均吞吐量	58

表目錄
表3.1 型態一細胞邊緣分配資源的優先權(地帶1、3、5)	42
表3.2 型態一細胞邊緣分配資源的優先權(地帶2、4、6)	42
表3.3 使用者分配資源優先權	47
表4.1 實驗參數	51

[1]	3GPP TR 25.814 v7.1.0, “Physical layer aspects for evolved UTRA (Release 7),” Sept. 2006.
[2]	3GPP TR 36.814 v1.0.1, “Further Advancements for E-UTRA Physical Layer Aspects (Release 9),” Mar. 2009.
[3]	J. Li, H. Zhang, X. Xu, X. Tao, T. Svensson, C. Botella, B. Liu, “A Novel Frequency Reuse Scheme for Coordinated Multi-Point Transmission,” in Proc. IEEE Vehicular Technology Conference, pp. 1-5, May 2010.
[4]	R1-050507, “Soft frequency reuse scheme for UTRAN LTE,” Huawei, 3GPP TSG RAN WG1 Meeting #41, May 2005.
[5]	H. Jia, Z. Zhang, G. Yu, P. Cheng, and S. Li, “On the Performance of IEEE 802.16 OFDMA System under Different Frequency Reuse and Subcarrier Permutation Patterns,” in Proc. IEEE International Conference on Communications, pp. 5720- 5725, Jun. 2007.
[6]	H. Le, L. Zhang, X. Zhang, and D. Yang, “A Novel Multi-Cell OFDMA System Structure using Fractional Frequency Reuse,” in Proc. IEEE Personal, Indoor and Mobile Radio Communications, pp. 1-5, 2007.
[7]	K. T. Kim, S. K. Oh, “A Universal Frequency Reuse System in a Mobile Cellular Environment,” in Proc. IEEE Vehicular Technology Conference, pp. 2855-2859, April 2007.
[8]	K. T. Kim, S. K. Oh, “An Incremental Frequency Reuse Scheme for an OFDMA Cellular System and Its Performance,” in Proc. IEEE Vehicular Technology Conference, pp. 1504-1508, May 2008.
[9]	R1-082024, “A discussion on some technology components for LTE-Advanced,” Ericsson, 3GPP TSGRAN WG1 #53, May 2008.
[10]	R1-083569, “Further discussion on Inter-Cell Interference Mitigation through Limited Coordination,” Samsung, 3GPP TSGRAN WG1 #54bits, Oct. 2008.
[11]	R1-091688, “Potential gain of DL CoMP with joint transmission,” NEC Group, 3GPP TSGRAN WG1 #57, May. 2009.
[12]	3GPP RAN1 R1-050764, "Inter-cell interference Handling for E-UTRAN," Ericssion. 
[13]	M. Necker, "Interference coordination in cellular OFDMA network," IEEE Network, vol. 22, no.6, pp. 12-19, 2008.
[14]	W. Fu, Z. Tao, J. Zhang, D. P. Agrawal, "Clustering Based Fractional Frequency Reuse and Fair Resource Allocation in Multi-cell Networks," in Proc. IEEE International Conference on Communications, pp.1-5, May 2010.
[15]	Z. Lu, H. Tian, Q. Sun, B. Huang, S. Zheng, "An Admission Control Strategy for Soft Frequency Reuse Deployment of LTE Systems," in Proc. IEEE Consumer Communications and Networking Conference, pp. 1-5, Jan. 2010.
[16]	“WCDMA/UMTS第三代無線通訊系統 無線技術介紹,” http://loda.hala01.com/2009/04/wcdmaumts-第三代無線通訊系統-無線技術介紹/, March 2012.
[17]	3GPPTR25.813 v7.1.0. Evolved UTRA (E-UTRA) and Evolved UTRAN (E-UTRAN): Radio interface protocol aspects [S]. 2006.
[18]	3GPPTR25.913 v7.3.0. Requirements for Evolved UTRA (E-UTRA) and Evolved UTRAN (E-UTRAN) [S]. 2006.
[19]	“LTE-A 引領MBB新紀元,” http://tw.myblog.yahoo.com/jw!9EJiHLKAHxVSpfxCMm2qVDDHATEq1w--/article?mid=6548&prev=166&next=6547, Feb. 2012
[20]	陳逸萍, ”LTE(Long Term Evolution)/4G發展現況,” LTE現況與發展報告.pdf, March 24, 2012
[21]	H. Khan, M. A. Qadeer, J. A. Ansari, S. Waheed, “4G as a Next Generation Wireless Network,” in Proc. IEEE International Conference on Future Computer and Communication, pp. 334-338, April 2009.
[22]	G. Pinero, C. Botella, A. Gonzalez, M. de Diego and N. Cardona, “Downlink power control and beamforming for a cooperative wireless system,” in Proc. IEEE Personal, Indoor and Mobile Radio Communications, pp. 974-978, Setp. 2004.
[23]	C. Nie, P. Liu, S. Panwar, “Interference Management using Frequency Planning in an OFDMA based Wireless Network,” in Proc. IEEE Wireless Communications and Networking Conference , pp.998-1003, March 2011.
[24]	D. Jia, G. Wu, S. Li, G.Y. Li, X. Zhu, ” Dynamic Soft-Frequency Reuse with Inter-Cell Coordination in OFDMA Networks,” in Proc. International Conference on Computer Communications and Networks, pp.1-6, Aug. 2011.
[25]	P. Wang, C. Liu, R. Mathar, “Dynamic Fractional Frequency Reused Proportional Fair in Time and Frequency Scheduling in OFDMA Networks,” in Proc. IEEE International Symposium on Wireless Communication Systems, pp.745-749, Nov. 2011.