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研究生:徐士為
研究生(外文):Shih-Wei Shiu
論文名稱:正交分頻多工系統之低計算複雜度峰值對平均功率比值降低技術之研究
論文名稱(外文):Research on Low Computational-Complexity Peak-to-Average Power Ratio Reduction Techniques for OFDM Systems
指導教授:連振凱連振凱引用關係
指導教授(外文):Jenn-Kaie Lain
學位類別:碩士
校院名稱:國立雲林科技大學
系所名稱:電子與資訊工程研究所
學門:工程學門
學類:電資工程學類
論文種類:學術論文
論文出版年:2009
畢業學年度:97
語文別:中文
論文頁數:67
中文關鍵詞:部分序列傳送連續性螞蟻演算法峰值對均值功率比正交分頻多工系統螞蟻最佳化演算法
外文關鍵詞:OFDMPAPRPTSACORACO
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正交分頻多工(OFDM)傳輸技術在高速無線網路中是個相當熱門的技術,OFDM可以抵抗頻率選擇衰減現象以及有效地抵抗符元間相互干擾。近十幾年來,此技術已應用在非常多的通訊標準上,例如: 非對稱的數位用戶網路(ADSL)、數位音頻廣播(DAB)、數位視頻廣播(DVB)、WiMAX (802.16)和寬頻區域網路802.11(a,b,g)等。
雖然OFDM 有許多好處以至於應用廣泛,不過還是有一些缺點存在,其中一項就是它具有高的峰值對平均功率比(PAPR)。高的峰值對平均功率比對於功率放大器來說,會造成功率放大器需要過大的線性操作區,如此容易導致信號失真嚴重。部份傳輸序列(PTS)為公認效果不錯的方法之一,它能有效降低峰值對平均功率比,並且因為它是線性運算,對OFDM 訊號本身沒有破壞性的干擾作用,在不考慮雜訊情況下,接受端可以完整的將訊號解調回來。但是由於PTS演算法複雜度太高,所以本研究中針對PTS的高複雜度運算做改善,我們使用PTS結合螞蟻演算法和連續性的螞蟻演算法來降低複雜度提供更有效率的運算,在模擬結果中這兩種新的方法都能夠有效的降低峰值對平均功率比並且使用較低的運算複雜度來實行。
Orthogonal frequency division multiplexing (OFDM) is a very effective technique for the wireless high-speed data transmission since its robustness for selective fading channel and inter-symbol interference (ISI). Recently, OFDM has been used widely in many kinds of communication standards, for example digital audio broadcasting (DAB), wireless local-area network (WLAN) IEEE 802.11, WiMAX (IEEE 802.16) and Asymmetric Digital Subscriber Line (ADSL).
One serious disadvantage of OFDM is high peak-to-average power ratio (PAPR). If the transmitted signal has high PAPR, the D/A converters and amplifiers need to have a large dynamic range. Although a lot of schemes can reduce PAPR efficiently, we only focus on partial transmit sequence (PTS) algorithm. PTS is used to reduce PAPR effectively with linear operation, it does not have destructive and interfered effect for the OFDM signal itself. Without considering noise effects, the received signal can be demodulated perfectly at receiver end. Nevertheless, the complexity of PTS is too high. In this thesis, we develop a kind of simpler Ant-Colony-Optimization algorithms and Ant colony optimization for continuous domains to combine PTS for the purpose of reducing the computational-complexity in the original PTS. The results show that new methods can reduce PAPR effectively with emphasis on their low complexity.
中文摘要 i
英文摘要 ii
誌謝 iv
目錄 v
表目錄 vii
圖目錄 viii
第一章 緒論 1
1.1 研究背景 1
1.2 研究動機 1
第二章 正交分頻多工系統介紹 3
2.1 正交分頻多工系統架構 3
2.2 正交分頻多工系統的正交特性 6
2.3 循環字首(Cyclic Prefix, CP) 7
2.4 正交分頻多工系統之優缺點 9
第三章 PAPR及降低PAPR方法介紹 11
3.1 PAPR定義 11
3.2 正交分頻多工系統中PAPR的影響 12
3.3 PAPR的機率分佈 13
3.4 降低PAPR方法 14
3.4.1 截波法(Clipping) 14
3.4.2 峰值視窗(Peak Windowing) 16
3.4.3 編碼(Coding) 16
3.4.4 符元重組(Symbol Scrambling) 16
3.4.5 選擇性映射(SLM) 17
3.4.6 部分傳送序列(PTS) 20
3.5 PTS複雜度問題 25
第四章 PTS降低複雜度方法 26
4.1 螞蟻演算法介紹 26
4.2 離散螞蟻演算法 28
4.3 離散螞蟻演算法結合PTS 31
4.4 連續性的螞蟻演算法 38
4.5 連續性的螞蟻演算法結合PTS 41
第五章 模擬結果 46
5.1 離散螞蟻演算法結合PTS模擬(PTS-ACO) 46
5.2 連續性的螞蟻演算法結合PTS模擬(PTS-ACOR) 49
第六章 結論 53
參考文獻 54
[1]B. R. Saltzberg, “Performance of an Efficient Parallel Data Transmission System,” IEEE Transactions on Communication Tech, Vol. 15, Issue 6, pp. 805 – 811, Dec. 1967.
[2]R. V. Nee and R. Prasad, “OFDM for Wireless Multimedia Communications”, Artech House, 2000.
[3]Zhao, Y. and Haggman, S.-G, “Sensitivity to Doppler shift and carrier frequency errors in OFDM systems-the consequences and solutions”, Vehicular Technology Conference, 1996. ''Mobile Technology for the Human Race''., IEEE 46th ,Vol. 3, 28 April-1 May 1996 Page(s):1564 - 1568 vol.3
[4]Young-Seo Park and Miller, S.L, “Peak-to-average power ratio suppression schemes in DFT based OFDM”, Vehicular Technology Conference, 2000. IEEE VTS-Fall VTC 2000. 52nd, Vol. 1, 24-28 Sept. 2000 Page(s):292 - 297 vol.1
[5]R.van Nee and A. de Wild, "Reducing the peak-to-average power ratio of OFDM," in proc. IEEE Vehicular Technology Conf(VTC), vol.3, May 1998,pp. 2072-2076.
[6]X. Li and L. J. Cimini, Jr., “Effects of Clipping and Filtering on the Performance of OFDM,” IEEE Communication Letter, Vol. 2, pp. 131-133, May 1998.
[7]R. O''Neill, L.B. Lopes, “Envelope variations and spectral splatter in clipped multicarrier signals,” Personal, Indoor and Mobile Radio Communications, 1995. PIMRC''95. Vol. 1, pp. 71-75, Sep. 1995.
[8]R. van Nee, “OFDM Codes for Peak-to-Average Power Reduction and Error Correction,” IEEE Global Telecommunication Conference, Vol. 1, pp. 740-744, Nov. 1996.
[9]J. A. Davis and J. Jedwab, “Peak-to-mean power control and error correction for OFDM transmission using Golay sequences and Reed-Muller codes,” Electronics Letters, Vol. 33, Issue 4, pp. 267-268, Feb. 1997.
[10]S. H. Muller and J. B. Huber, “A Comparison of Peak Power Reduction Schemes for OFDM,” IEEE Global Telecommunications Conference, 1997. GLOBALCOM ’97, Phoenix, AZ, pp. 1-5, Nov. 1997.
[11]S. H. Muller and J. B. Huber, “OFDM with reduced peak-to-average power ratio by optimum combination of partial transmit sequences,” Electronics Letters, Vol. 33, Issue 5, pp. 368-369, Feb. 1997.
[12]Dorigo, M., and Gambardella, L. M., “Ant Colony System: A Cooperative Learning Approach to the Traveling Salesman Problem.” IEEE Transactions on Evolutionary Computation, Vol.1, No.1, pp.53-66, 1997.
[13]Dorigo, M., Maniezzo, V., and Colorni, A., “The ant system: optimization by a colony of cooperating agents.” IEEE Transactions on Systems, Man, and Cybernetics--Part B , Vol. 26, No. 2, pp. 29-41, 1996.
[14]Deneubourg, J., Goss, S., Franks, N., Sendova-Franks, A., Detrain, C. and Chretien, L., “The dynamics of collective sorting robot-like ants and ant-like robots.” Proc. Of the 1st Conf. on Sim. of Adaptive Behavior, pp. 356-363, 1991.
[15]Shelokar, P. S., Jayaraman, V. K. and Kulkarni, B. D., “An ant colony approach for clustering.” Analytica Chimica Acta, Vol. 509, No.2, pp. 187-195, 2004.
[16]K. Scoha, M. Dorigo (2008) “Ant Colony Optimization for Continuous Domains”. European Journal of Operational Research, Vol. 185, No. 3, pp.1155-1173.
[17]M. Guntsch, M. Middendorf "A population based approach for ACO" Applications of Evolutionarz Computing, Proceedings of EvoWorkshops , vol. 2279, pp. 71–80.2002.
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