| 研究生: |
李達龍 Da-Long Lee |
|---|---|
| 論文名稱: |
使用MMSE等化器的Filterbank OFDM系統探討 The Investigation of Filterbank OFDM Systems with MMSE Equalization |
| 指導教授: |
張大中
Dah-Chung Chang |
| 口試委員: | |
| 學位類別: |
碩士 Master |
| 系所名稱: |
資訊電機學院 - 通訊工程學系 Department of Communication Engineering |
| 畢業學年度: | 93 |
| 語文別: | 中文 |
| 論文頁數: | 76 |
| 中文關鍵詞: | IEEE 802.11a 、多載波調變 、MMSE 等化器 、正交分頻多工系統 、濾波器組 |
| 外文關鍵詞: | multicarrier modulation, MMSE equalization, OFDM, Filterbank, IEEE 802.11a |
| 相關次數: | 點閱:7 下載:0 |
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在本篇論文中將討論使用filterbank的多載波系統應用於無線室內的環境中。使用filterbank取代DFT做為OFDM系統的主要目的為其較佳的頻譜特性,能夠降低interchannel interference (ICI),甚至可以省去CP,增加OFDM傳輸效率。我們首先討論filterbank設計參數的選定; 接著提出三種具MMSE等化器的接收機架構,並對這三種等化器組態的特性做探討及比較。此外,將使用MMSE等化器的Filterbank OFDM系統,和現行的IEEE 802.11a系統做比較。整個模擬環境設定參考 IEEE 802.11a 之 OFDM 系統規格設計,採用 64點 FFT 系統之次頻帶。雜訊源和通道考慮 AWGN 和 Multipath Fading,另外我們將考慮 narrowband interference 之影響。結果顯示了Filterbank-based 多載波通訊系統具有較為優越的傳輸性能,但須付出較高複雜度和較長之訓練序列。
In this thesis we investigate the use of the filterbank-based multicarrier communication system in the indoor environment. The filterbank-based system as opposed to DFT OFDM, is that the property of low sidelobe in filterbank can reduce intercarrier interference which is typically serious for some situations in OFDM. First, the choice of the filterbank design parameters is discussed. The receiver characteristics of different equalization structures are studied, and their complexity and performance are compared as well. Finally, the IEEE 802.11a OFDM system is compared with the filterbank-based multicarrier proposal. A quasi-static channel is used and the noise considers narrowband interference and AWGN. The results show that the performance of filterbank-based system is superior to the IEEE 802.11a OFDM system with the penalty of complexity and longer training sequence.
[1] IEEE Std. 802.11a, ”Wireless LAN medium access control (MAC) and physical layer (PHY) specifications: High-speed physical layer in the 5GHz band,” Nov. 1999.
[2] A.D.Rizos, J.G.Proakis, and T.Q.Nguyen, “Comparison of DFT and Cosine Modulated Filter Banks in Multicarrier Modulation,” Proceedings of IEEE Globecom’94, pp.687-691, 1994.
[3] S.Govardhanagiri, T.Karp, P.Heller, and T.Nguyen, “Performance Analysis of Multicarrier Systems Using Cosine Modulated Filter Banks,” Proc. IEEE ICASSP, Vol. 3, pp. 1405-1408, Phoenix, USA, March 1999.
[4] Lin, Y-P., Vaidyanathan, P. P., Akkarakaran, S., and Phoong, S-M., “On the duality of optimal DMT systems and biorthogonal subband coders,” Pro. IEEE ICASSP, Istanbul, June 2000.
[5] T. Ihalainen, J. Alhava, A. Viholainen, X. Hongnian, J. Rinne, and M. Renfors, “On the performance of filter bank based multicarrier systems in xDSL and WLAN applications,” in Pro. Int. Conf. on Communications, New Orleans, Louisiana, USA, June 18-22, 2000, pp. 1120-1124.
[6] A. Viholainen, T. Saramäki, and M. Renfors, “Nearly perfect-reconstruction cosine-modulated filter bank design for VDSL modems," in Proc. Int. Conf. on Electronics, Circuits and Systems, Pafos, Cyprus, Sept. 5-8, 1999, pp. 373-376.
[7] Alexander M. Wyglinski , Peter Kabal , and Fabrice Labeau ,“Adaptive Filterbank Multicarrier Wireless Systems for Indoor Environments,” Proc. IEEE Vehicular Technol. Conf. (Vancouver, BC), pp. 336-340, Sept. 2002.
[8] Vandendorpe Luc, “Performance analysis of IIR and FIR linear and decision-feedback MIMO equalizers for transmultiplexers” , ICC''97 - IEEE International Communications Conference, Montreal, Canada, June 1997, Proceedings, , pp. 657-661
[9] D.-C. Chang, W.-R. Wu, “The Adaptive Transmultiplexer Using Multichannel Fast RLS Algorithms,” International Symposium on Communications, Kaohsiung, Taiwan, 1999.
[10] R.E. Crochiere, and L.R.Rabirier, Multirate Digital Processing, Pretice-Hall, Englewood Cliffs, 1983.
[11] Hua Xu, W.-S. Lu, and Andreas Antonions, ”Efficient Iterative Design Method for Cosine-Modulated QMF Banks,” IEEE Trans. Signal Processing, Vol. 44, No. 7, pp.1657-1668, July 1996.
[12] A. Viholainen, "Transmultiplexer design for VDSL modems," M.Sc. Thesis, Department of Information Technology, Tampere University of Technology, Finland, Aug. 1998.
[13] P.P.Vaidyanathan, Multirate Systems and Filter Banks, Englewood Cliffs, NJ: Prentice-Hall, 1993.
[14] H.S. Malvar, "Extended lapped transforms: properties, applications, and fast algorithms", IEEE Transactions on Signal Processing, vol. 40, pp. 2703-2714, Nov. 1992
[15] J.-J. van de Beek, O. Edfors, M. Sandell, S. K. Wilson, and P. O. Borjesson,
“On channel estimation in OFDM systems,” in Proc. IEEE 45th Vehicular Technology Conf, Chicago, IL, Jul. 1995, pp. 815–819.
[16] A. J. Redfern, “Receiver Window Design for Multicarrier Communication Systems,” IEEE Journal on Selected on Selected Area in Communications, Vol. 20, No. 5, pp.1029-1036, 2002.
[17] T. Karp and N. J. Fliege, “Modified DFT Filter Banks with Perfect Reconstrution “. In IEEE Trans. on Circuits and Systems II, Vol. 46, Issue 11, November 1999, pp. 1404-1414.