博碩士論文 100523016 詳細資訊




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姓名 張顥薰(Hao-hsun Chang)  查詢紙本館藏   畢業系所 通訊工程學系
論文名稱 中繼網路於多路徑通道環境下基於領航信號的通道估測方法研究
(Pilot-Based Channel Estimation Methods for Wireless Relay Networks in Multipath Channels)
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摘要(中) 隨著無線通訊技術發展與多媒體應用服務成長,系統營運商與用戶端皆期許以提供或擁有更高傳輸速率及更好服務品質,傳統點對點傳輸(Point-to-point communication)技術受限於通道衰減、遮蔽效應與多路徑通道效應影響,用戶於蜂巢細胞覆蓋範圍邊際或處於重度遮蔽環境下訊號通訊品質時常低落。中繼站網路(Relay Networks)為近年廣泛討論與研究的新興通訊概念,網路發射端或稱為源節點(Source node)可透過其附近中繼站資源來轉遞訊號至接收端或稱目標節點(Destination node),利用空間分集效益(Spatial Diversity Gain)增加通道多樣性以大幅改善傳統點對點傳輸通訊品質不佳問題或增加無線通訊網路細胞覆蓋範圍。
為了更好的利用中繼網路的優點,可獲得的通道狀態資訊量(Channel State Information)是決定效能的主要因素,目前研究文獻大都假設中繼端及接收端可獲得所有的通道資訊,包含中繼網路每條路徑或每次跳躍的通道資訊。
在本論文中,我們考慮在放大轉遞(Amplify-and-Forward)中繼網路下進行通道估測,並提出兩種基於領航訊號的估測演算法:最大概似估測(maximum likelihood estimation)和最小均方誤差估測(minimum mean square error estimation)。最大概似估測的優點是易於實現,因為不需要知道通道統計特性(channel statistics),降低其計算複雜度,但在效能會較差。相反的,最小均方誤差估計儘管需要更高的計算複雜度,但由於它利用通道統計特性有效的增進系統效能。
接著我們討論不同的通道估測方法,可概分為兩類:串接式通道估測(Integrated Channel Estimation)及分離式通道估測(Disintegrated Channel Estimation),串接式通道估測方法在發射端傳送領航訊號(pilot signal),中繼站接收後將其功率放大,同時引入另一領航訊號與接收訊號一同轉傳至接收端。接收端可藉以估測「中繼端-接收端」通道及「發射端-中繼端-接收端」串接式通道;分離式通道估測方法則是在接收端先估測「中繼端-接收端」通道,再利用估測到的「中繼端-接收端」通道協助估測「發射端-中繼端」通道。模擬結果顯示在分離式通道估測方法下有較佳的效能。
於傳統點對點通道估測方法中,時域通道估測方法可利用功率延遲概觀(Power delay profile)特性強化通道估測效能,因此其效能遠優於頻域通道估測方法。因此我們也在中繼網路使用時域通道估測方法來增進效能。
因為中繼端的高斯雜訊對於「發射端-中繼端-接收端」串接式通道估測干擾,我們藉由雜訊濾除矩陣(Denoising Matrix)抑制雜訊。分別對串接式通道估測和分離式通道估測使用,模擬結果顯示有不錯的效能增進。
最後會將串接式通道估測和分離式通道估測在不同領航訊號數目與不同權重矩陣下的效能比較。
摘要(英) Recently, wireless communication technology and media application service grows faster than ever, providers and users all expect higher transmission rate and better Quality of Service (QoS). Because the conventional point-to-point communication is susceptible to channel fading, shadowing effect, and multipath channel effect, communication quality at cell edge or severe shadowing environments is low. Relay networks have been emerged as a promising technology to improve the link quality in severe channel fading and shadowing environments or increase the cell coverage by spatial diversity gain.
In most of the existing literature, it is assumed that the perfect channel state information (CSI) of each link are available at the destination. However, the successful implementation of the relay networks relies on the accurate CSIs of each link.
In this thesis, we propose time-domain channel estimators for relay networks in multipath channels. Based on the maximum likelihood (ML) and minimum mean square error (MMSE) criteria, two kinds of channel estimation methods, integrated and disintegrated, are investigated for estimating relay-to-destination (RD), source-to-relay (SR), or their cascaded channel links. A denoise-and-forward (DF) estimator is proposed to further improve the performance by imposing a denoising matrix to effectively suppress the noise enhancement effect at the relay node. Computer simulation is used to demonstrate the effectiveness of the proposed time-domain channel estimation methods.
關鍵字(中) ★ 中繼網路
★ 通道估測
★ 多路徑通道
★ 串接式通道
關鍵字(英) ★ relay networks
★ channel estimation
★ multipath channels
★ cascaded channels
論文目次 致謝 ........................................................................................................................................... ii
摘要 .......................................................................................................................................... iii
目錄 .......................................................................................................................................... vi
圖目錄 .................................................................................................................................... viii
表目錄 ...................................................................................................................................... ix
符號說明 ................................................................................................................................... x
第一章 緒論 .............................................................................................................................. 1
1.1 研究動機與背景 .............................................................................................................. 1
1.2 文獻探討 ......................................................................................................................... 2
1.3 論文架構 .......................................................................................................................... 3
第二章 行動無線通道特性 ...................................................................................................... 4
2.1 無線通道模型 ................................................................................................................. 4
2.2 大尺度衰減模型 ............................................................................................................. 4
2.3 小尺度衰減模型 ............................................................................................................. 5
2.3.1 多路徑效應 .............................................................................................................. 5
2.3.1.1 延遲擴展(Delay Spread)及功率延遲概觀 ................................................. 6
2.3.1.2 同調頻寬(Coherence Bandwidth)與頻率選擇性衰減 ............................... 7
2.3.2 都普勒擴散(Doppler Spread) ............................................................................. 8
第三章 中繼站網路系統模型 ................................................................................................ 10
3.1 中繼站網路簡介 ............................................................................................................ 10
3.2 放大轉遞中繼網路架構 ................................................................................................ 11
第四章 串接式通道估測方法 ................................................................................................ 14
4.1 串接式通道估測器 ....................................................................................................... 14
4.2 理想串接式通道估測器 ............................................................................................... 18
第五章 分離式通道估測方法 ................................................................................................ 21
5.1 分離式通道估測器 ........................................................................................................ 21
5.2 理想分離式通道估測器 ............................................................................................... 25
第六章 雜訊濾除轉遞(Denoise-and-forward Relay)估測器 ............................................ 28
6.1 最佳雜訊濾除矩陣設計 ............................................................................................... 30
6.2 以投影矩陣設計雜訊濾除矩陣 ................................................................................... 32
6.3 以複立葉轉換設計雜訊濾除矩陣 ............................................................................... 34
第七章 模擬結果與討論 ........................................................................................................ 36
7.1 模擬參數 ....................................................................................................................... 36
7.2 均方誤差效能在不同串接式通道估測演算法下比較 ............................................... 36
7.3 均方誤差在不同分離式通道估測演算法下比較 ....................................................... 40
7.4 均方誤差在不同串接式與分離式通道估測演算法比較 ........................................... 43
第八章 結論 ............................................................................................................................ 46
參考文獻 ................................................................................................................................. 47
參考文獻 [1] A. Nosratinia, T. E. Hunter, and A. Hedayat, “Cooperative communication in wireless networks,” IEEE Commun. Mag., vol. 42, no. 10, pp. 74-80, Oct. 2004.
[2] Z. Lin, E. Erkip, and M. Ghosh, “Adaptive modulation for coded cooperative systems,” in Proc. SPAWC. ’06, Jun. 2005, pp. 615–619.
[3] J. Laneman, D. Tse, and G. Wornell, “Cooperative diversity in wireless networks: Efficient protocols and outage behavior,” IEEE Trans. Inf. Theory, vol. 50, no. 12, pp. 3062–3080, Dec. 2004.
[4] B. Can, H. Yomo, and E. De Carvalho, “Hybrid forwarding scheme for cooperative relaying in OFDM based networks,” in Proc. ICC ’06, Jun. 2006, vol. 10, pp. 4520–4525.
[5] A. S. Lalos, A. A. Rontogiannis, and K. Berberidis, “Frequency domain channel estimation for cooperative communication networks,” IEEE Trans. Signal Process., vol. 58, no. 6, pp. 3400-3405, June 2010.
[6] M. G. Song, K. Dongsik, and G. H. Im, “Recursive channel estimation method for OFDM-based cooperative systems,” IEEE Commun. Lett., vol. 14, no. 11, pp. 1029-1031, Nov. 2010.
[7] S. K. Jo, J. M. Choi, J. S. Baek, and J. S. Seo, “Channel estimation with optimal power controls in amplify-and-forward relay networks,” IEEE Wireless Commun. Lett., vol. 2, no. 1, pp. 10-13, Feb. 2013.
[8] M. PremKumar, V. N. SenthilKumaran, and S. J. Thiruvengadam, “Channel estimation technique for amplify and forward based wireless relay networks using BLUE approach,” in Proc. WiCOM, Sep. 2011, pp. 1-4.
[9] F. Gao, T. Cui, and A. Nallanathan, “On channel estimation and optimal training design for amplify and forward relay networks,” IEEE Trans. Wireless Commun., vol. 7, no. 5, pp. 1907-1916, May 2008.
[10] C. S. Patel and G. L. Stuber, “Channel estimation for amplify and forward relay based cooperation diversity systems,” IEEE Trans. Wireless Commun., vol. 6, no. 6, pp. 2348-2356, June 2007.
[11] O. Amin, B. Gedik, and M. Uysal, “Channel estimation for amplify-and-forward relaying: Cascaded against disintegrated estimators,” IET Commun., vol. 4, no. 10, pp. 1207-1216, July 2010.
[12] C. Zhang, J. Zhang, W. D. Wang, and G. Wei, “Distributed space-time decoding with Two-Pilot channel estimation for wireless relay networks,” in Proc. IEEE PIMRC., Sep. 2009, pp. 2320-2324.
[13] M. L. Liu, J. H. Zhang, Y. Y. Zhang, and Y. Liu, “A channel estimation scheme for amplify-and-forward OFDM relay networks,” in Proc. VTC., Sep. 2009, pp. 1-5.
[14] M. Morelli and U. Mengali, “A comparison of pilot-aided channel estimation methods for OFDM systems,” IEEE Trans. Signal Process., vol. 49, no. 12, pp. 3065-3073, Dec. 2001.
[15] J. G. Proakis and H. Arslan, Digital Communications,5th ed. New York: McGraw-Hill, 2008.
[16] Theodore S. Rappaport, Wireless Communications Principles and Practice, 2nd ed. Prentice Hall, Upper Saddle River, NJ, 2002.
[17] 林高洲,「無線通信系統發展新趨勢-智慧型合作式通信網路」, 中華民國電子零件認證委員會(IECQ), Sep. 2009, pp. 44-49.
[18] 吳文榕, 曾凡碩, 謝弘道,「合作式通訊之現況與發展」, NCP Newsletter, No. 31, Sep. 2011, pp. 2-7.
[19] S. Coleri, M. Ergen, A. Puri, and A. Bahai, “Channel estimation techniques based on pilot arrangement in OFDM systems,” IEEE Trans. Broadc., vol. 48, no. 3, Sep. 2002.
[20] D. G. Luenberger, Optimization by vector space methods. New York: Wiley, 1969, pp. 88-90.
[21] J. Laiho, A. Wacker, and T. Novosad, Radio Network Planning and Optimisation for UMTS. New York: Wiley, 2002.
指導教授 古孟霖(Meng-lin Ku) 審核日期 2013-8-26
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