臺灣博碩士論文加值系統

本論文主要目的，由正交分頻多重接取系統(Orthogonal Frequency Division Multiple Access,OFDMA)所演變至今的單載波分頻多重存取(Single carrier frequency division multiple access, SC-FDMA )系統技術中的區域式分頻多重存取(L-FDMA)載波映射系統，進行峰值對平均功率比(PAPR)降低及比較。所採用是截波(Clipping)技術[7]及擴壓(Companding)技術[8]，並且於IEEE 802.16所提出之SUI(Stanford University Interim)通道模型的中的SUI-3通道模型與另一個國際電信聯盟無線電通信組(ITU)無線通道中的低速通道(Pedestrian A)與高速通道(Vehicular A)進行通道模擬，確認峰值對平均功率比(PAPR)降低後的BER(Bit Error Rate)效能影響狀況。由模擬結果指出，於LFDMA系統下分別僅單獨加入截波技術與擴壓技術後，PAPR僅有降低約1dB左右。但結合兩者技術後，於QPSK調變下的模擬結果，PAPR約可降低至4.8dB，較原系統的7.5dB的PAPR還低約2.7dB左右。而在16QAM的調變下，PAPR約可降低至5.1dB，較原系統的8.2dB的PAPR還低約3.1dB左右。進而比較於OFDMA系統使用QPSK調變系統下，可降低至6dB左右的PAPR，較原系統的10.2dB的PAPR還低約4.2dB。且於各個通道效能模擬表現下，加入PAPR降低的技術後，可擁有與原系統類似的BER，並不會造成原系統效能大幅降低。

The main purpose of this thesis is to investigate the PAPR reduction comparison for the evolved localized (LFDMA) subcarrier mapping of the OFDMA technology, SC-FDMA. Clipping and Companding are used as the PAPR reduction technique. The channel models used in the simulation are SUI-3 channel model of IEEE 802.16 SUI proposed along with the ITU channel models in the low-speed channel(Pedestrian A) and high-speed channel (Vehicular A). The simulation are conducted to reveal BER performance under the conditions with the PAPR reduction techniques. As indicated by the simulation results, under the LFDMA systems, there is about 1 dB PAPR reduction by using either Clipping technology or Companding technology separately. If the combination of the two technologies is employed, PAPR can be reduced to be approximately 4.8dB in the simulation under QPSK modulation. Compared with the PAPR of the original system(7.5dB), it is reduced by about 2.7dB. In the 16QAM modulation under, PAPR can be reduced to be about 5.1dB. Compared with the original system (8.2dB), it is reduced by about 3.1dB. Then, we make comparison in OFDMA systems by using QPSK modulation, PAPR can be reduced to be about 6dB. Compared with the original system(10.2dB), it is reduced by about 4.2dB. As revealed in the performance curves, adding PAPR reduction techniques have the similar BERs of the original systems, and will not cause significant reduction of the original system performance.

中文摘要 i
英文摘要 iii
誌謝 v
目錄 vi
圖目錄 viii
表目錄 ix
一、 緒論 1
1-1 研究動機 1
1-2 本論文內容架構 1
二、 SC-FDMA介紹 2
2-1 SC/FDE與OFDM原理 2
2-2 SC/FDE與 OFDM優缺點比較 4
2-3 SC-FDMA 概述 5
2-4 SC-FDMA 子載波映射方式 8
2-5 SC-FDMA 訊號時域中表現 11
2-5-1 I-FDMA時域訊號 11
2-5-2 L-FDMA時域訊號 12
三、 PAPR 15
3-1 概述 15
3-2 峰均值功率比的定義 15
3-3 SC-FDMA峰均值功率比 18
四、 PAPR降低技術 21
4-1 波峰裁減(Clipping) 21
4-2 u-law Companding 技術 22
五、 模擬 23
5-1 模擬參數 23
5-2 模擬通道模型 24
5-3 SC/FDE 與OFDM效能比較 26
5-4 OFDMA 系統模擬 29
5-5 SC-FDMA系統模擬 30
5-6 Companding技術模擬 34
5-7 Clipping技術模擬 36
5-8 降低OFDMA系統 PAPR 39
5-9 降低 SC-FDMA系統PAPR 40
六、 結論 42
參考文獻 44

[1] E. Dahlman, S. Parkvall, J. Skold, and P. Beming, ,3G evolution HSPA and LTE for mobile broadband., Academic Press is an Imprint of Elsevier,2007.
[2] H. G. Myung, ,Single Carrier Orthogonal Multiple Access Technique for Broadband Wireless Communication.,Polytechnic University,January 2007.
[3] H. G. Myung, J. Lim, and D.J. Goodman, “Peak-to-average power ratio of single carrier FDMA signals with pulse shaping,” IEEE 17-th International Symposium on PIMRC, September 2006.
[4] Md. Masud Rana, “Performance of Sub-carrier Mapping in Single Carrier FDMA Systems Under Radio Mobile Channels,” 13th International Conference on Computer and Information Technology (ICCIT 2010) 23-25 ,December, 2010.
[5] V. Erceg, K.V.S. Hari, M.S. Smith, D.S. Baum et al, “Channel Models for Fixed Wireless Applications”, Contribution IEEE 802.16.3c-01/29r1, Feb. 2001.
[6] 3GPP TS 25.101 “ User Equipment (UE) radio transmission and reception. (FDD) ” , V9.1.0 (2009-09)
[7] X. Li and L. J. Cimini Jr., “Effect of clipping and filtering on the performance of OFDM,” IEEE Commun. Lett., vol. 2,, pp. 131-133, May 1998.
[8] X. Wang, T. T. Tjhung, and C. S. Ng, “Reduction of peak-to-average power ratio of OFDM system using a companding technique,” IEEE Trans. Broadcast., vol. 45, pp. 303-307, Sep. 1999
[9] R. V. Nee and R. Prasad, OFDM for Wireless Multimedia Communications., Artech House, Jan. 2000.
[10] Berardinelli G., Ruiz de Temino L.A.,Frattasi, S.,Rahman, M.,Mogensen, P.,Aalborg Univ.,Aalborg , “ OFDMA vs. SC-FDMA: performance comparison in local area imt-a scenarios ” , IEEE Wireless Communications Magazine , vol.15, Issue.5, October , 2008, pp. 64-72
[11] Shi Songsong ,FengChunyan ,GuoCaili , “ A Resource Scheduling Algorithm Based on User Grouping for LTE-Advanced System with Carrier Aggregation ” , Computer Network and Multimedia Technology, International Symposium, Jan, 2009
[12] H. G. Myung, K. Jung-Lin Pan, R. Olesen , D. Grieco, “Peak Power Characteristics of Single Carrier FDMA MIMO Precoding System”, Vehicular Technology Conference Fall (VTC 2007-Fall), 2007
[13] J. Noh and S. Oh , “ Distributed SC-FDMA Resource Allocation Algorithm based on the Hungarian Method ” , in Proc. VTC Fall, 2009
[14] Y.Cho,J.Kim,W.Yang,C.Kang,,MIMO-OFDM Wireless Communications with　MATLAB.John Wiley &; Sons, 2010.
[15] J. Li, Y. Du, and Y. Liu, “Comparison of Spectral Efficiency for OFDM and SC-FDE under IEEE 802.16 Scenario,” Proceedings of the 11th IEEE Symposium on Computers and Communications (ISCC'06), 2006.
[16] T. Jiang and Y. Wu, “An Overview: Peak-to-Average Power Ratio Reduction Techniques for OFDM Signals”, IEEE Transactions on Broadcasting, vol. 54, no. 2, pp. 257-268, Jun. 2008.
[17] Cristina Ciochina and Hikmet Sari, “A Review of OFDMA and Single-Carrier FDMAM ”, Advances in electromics and telecommunications, vol. 1, no 1, April 2010.