因為提供了好的頻譜緊密度及能有效提供頻率分集能力，頻域預編碼式正交分頻多工與正交分頻多重存取系統是有效率的方波成形正交分頻多工與正交分頻多重存取系統。本論文旨在更進一步地探討頻域預編碼式正交分頻多工與正交分頻多重存取系統。在本論文的第一部分中，我們針對使用交織子載波分配之正交分頻多重存取系統與零插入正交分頻多工系統做探討，並提出兩種新的頻域預編編碼器，以用來改善頻譜緊密度與降低實現複雜度。明確地說，藉由最小化統治性頻譜係數，本研究建構出一可提供更高頻譜緊密度之相關性預編碼器。此外，我們也提出一多階式頻域預編碼技術以建構出一可提供f&;#8722;2L&;#8722;2 速度衰減之頻譜旁波並具有低實現複雜度之正交式預編碼器。此新正交式預編碼器建構之正交分頻多重存取信號或零插入正交分頻多工信號和原正交式預編碼器建構之正交分頻多重存取信號或零插入正交分頻多工信號有一樣的頻譜但只需要較低的實現複雜度。在本論文的第二部分中，我們提出了一種針對使用消除子載波之正交分頻多重存取系統的頻譜預編碼技術。在使用消除子載波之正交分頻多重存取系統中，分配給用戶的子載波被分為兩類，即資料子載波和消除子載波。資料子載波被用於發送資料符元而消除子載波被用於發送預編碼的符元，並賦予傳送之正交分頻多重存取信號非常小的功率頻譜的旁瓣衰減。我們設計了用於此系統之頻譜預編碼器並分析了用在消除子載波上的平均冗餘能量。在消除子載波的數量是固定的狀況下，所提出之頻譜預編碼式使用消除子載波之正交分頻多重存取信號可提供與現有的使用消除子載波之正交分頻多重存取信號等量的功率譜緊密度，同時消耗同等或更小的平均冗餘能量在消除子載波上。

Spectrally precoded orthogonal frequency-division multiplexing (OFDM) and its multiple access extension (OFDMA) are useful rectangularly pulsed OFDM and OFDMA signaling formats for they exploit high spectral compactness and frequency diversity characteristics. This thesis aims at exploring more on spectrally precoded OFDM and OFDMA. In the first part of the thesis, two new spectral precoders of the largest precoding rate are developed in order to provide improved spectral compactness and reduce implementation complexity, respectively, for OFDMA using cyclic prefix and interleaved subcarrier allocation (IOFDMA) and OFDM using zero padding (ZP-OFDM). Specifically, a new correlative precoder is developed and shown to minimize the dominant spectral coefficient among all correlative precoders of the largest precoding rate and thus can construct IOFDMA and ZP-OFDM signals providing extremely high spectral compactness. Besides, a multiple-stage spectral precoding technique is proposed to construct low-complexity orthogonally precoded IOFDMA and ZP-OFDM with power spectral sidelobes decaying as f^{-2L-2} for L>1, where L is the number of stages. The corresponding orthogonally precoded IOFDMA and ZP-OFDM signals conveying independent zero-mean data are respectively shown to provide the same power spectrum as existing orthogonally precoded IOFDMA and ZP-OFDM signals of the largest precoding rate, while requiring much less complexity. In the second part of this thesis, the cancellation-subcarrier-based (CS-based) spectral precoding scheme is proposed for OFDMA. In the scheme, the subcarriers allocated to a user are divided into two parts, namely, data subcarriers and cancellation subcarriers. The data subcarriers are used to transmit data symbols and the cancellation subcarriers are used to transmit precoded symbols and endow the resulting OFDMA signals with extremely small power spectral sidelobes decaying as f^{-2L-2} for L>1. When the number of cancellation subcarriers is assigned, the proposed CS-based spectrally precoded OFDMA signals are shown to provide comparable power spectral compactness to existing CS-based OFDMA signals while giving comparable or much smaller average redundant power on cancellation subcarriers.

Abstract i
Contents iii
List of Figures vi
List of Tables ix
1 Introduction 1
1.1 Review of Frequency-Domain Spectral Sidelobe Suppression Techniques 2
1.2 Review of Spectral Precoding Technique 4
1.3 Thesis Overview 6
1.4 Notations 7
2 Spectral Precoding for Cyclic-Pre xed OFDMA With Interleaved Subcarrier Allocation 9
2.1 Introduction 9
2.2 Spectrally Precoded IOFDMA System Model 10
2.3 PSD Equivalence Properties 17
2.4 New Correlative Precoder G(2)I;L 19
2.5 IOFDMA With Multiple-Stage Orthogonal Spectral Precoding 21
2.5.1 Design of GL&;#1048576;1,GL&;#1048576;2,...,G1 for Precoder H(L)I;log2 P 22
2.5.2 Solving ( L&;#1048576;l+1k=L Gk)tel&;#1048576;1 = 0 for GL&;#1048576;l+1 in Step l 23
2.5.3 Implementation Complexity Analysis 27
2.6 Numerical and Simulation Results 28
2.6.1 Power Spectral Compactness Characteristics 28
2.6.2 Error Performance Characteristics 30
2.6.3 PAPR Performance 33
2.6.4 Implementation Complexity Comparison 34
2.7 Chapter Summary 35
3 Spectral Precoding for Zero-Padded OFDM 37
3.1 Introduction 37
3.2 System Model 38
3.3 PSD Equivalence Properties 42
3.4 New Correlative Precoder G(2)L 44
3.5 ZP-OFDM With Multiple-Stage Orthogonal Spectral Precoding 46
3.5.1 Design of GL&;#1048576;1,GL&;#1048576;2,...,G1 for Precoder H(L)log2 N 47
3.5.2 Solving ( L&;#1048576;l+1k=L Gk)teel&;#1048576;1 = 0 for GL&;#1048576;l+1 in Step l 48
3.6 Numerical and Simulation Results 50
3.6.1 Power Spectral Compactness Characteristics 50
3.6.2 Error Performance Characteristics 50
3.6.3 PAPR Performance 53
3.6.4 Implementation Complexity Comparison 54
3.7 Chapter Summary 55
4 Cancellation-Subcarrier-Based Spectral Precoding for Cyclic-Pre xed OFDMA 57
4.1 Introduction 57
4.2 System Models 58
4.3 Precoder Design 60
4.3.1 Properties of Pr;min 62
4.3.2 Design Examples 63
4.4 Numerical and Simulation Results 65
4.4.1 Minimum Redundant Power Ratio Characteristics 65
4.4.2 Power Spectral Compactness Characteristics 68
4.5 Chapter Summary 71
5 Conclusion 72
Bibliography 74
Appendix A: Proof of Proposition 2-2 78
Appendix B: Proof of Proposition 2-3 79
Appendix C: Derivation of (2.10) 80
Appendix D: Proving That G(2)I;L is L-decaying and has (2.12) 81
Appendix E: Proof of Proposition 2-4 82
Appendix F: Derivation of (2.13) 83
Appendix G: A Lower Bound to Dl 84
Appendix H: Proof of Lemma G-2 85
List of Publications 88

[1] J. A. C. Bingham, “Multicarrier modulation for data transmission: An idea whose time has come,” IEEE Commun. Mag., vol. 28, no. 5, pp. 5-14, May 1990.
[2] T.-D. Chiueh and P.-Y. Tsai, OFDM Baseband Receiver Design for Wireless Communications. Singapore: Wiley, 2007.
[3] T. Schmidl and D. Cox, “Robust frequency and timing synchronization for OFDM,”IEEE Trans. Commun., vol. 45, no. 12, pp. 1613-1621, Dec. 1997.
[4] H. Yin and S. Alamouti, “OFDMA: A broadband wireless access technology,” in Proc. IEEE Sarnoff Symposium, pp. 1-4, Mar. 2006.
[5] Z. Cao, U. Tureli, and Y. D. Yao, “Deterministic multiuser carrier-frequency offset estimation for interleaved OFDMA uplink,” IEEE Trans. Commun., vol. 52, no. 9, pp. 1585-1594, Sep. 2004.
[6] S. W. Hou and C. C. Ko, “Multiple-access interference suppression for interleaved OFDMA system uplink,” IEEE Trans. Veh. Technol., vol. 57, no. 1, pp. 194-205, Jan. 2008.
[7] S. H. Song, G. L. Chen, and K. B. Letaief, “Localized or interleaved? A tradeoff between diversity and CFO interference in multipath channels,” IEEE Trans. Wireless Commun., vol. 10, no. 9, pp. 2829-2834, Sep. 2011.
[8] Z. Cao, U. Tureli and P. Liu, “Optimal subcarrier assignment for OFDMA uplink,” in Proc. Conf. Rec. 37th Asilomar Conf. Signals, Syst., Comput., pp. 708-712, Nov. 2003.
[9] I. Gepko, “Coding technique for out-of-band power emission reduction for multicarrier systems,” in Proc. EMC Europe 2011, pp. 278-283, Sep. 2011.
[10] K. Panta and J. Armstrong, “Spectral analysis of OFDM signals and its improvement by polynomial cancellation coding,” IEEE Trans. Consumer Electronics, vol. 49, no. 4, pp. 939-943, Nov. 2003.
[11] C.-D. Chung, “Correlatively coded OFDM,” IEEE Trans. Wireless Commun., vol. 5, no. 8, pp. 2044-2049, Aug. 2006.
[12] —, “Spectrally precoded OFDM,” IEEE Trans. Commun., vol. 54, no. 12, pp. 2173-2185, Dec. 2006.
[13] —, “Spectral precoding for rectangularly pulsed OFDM,” IEEE Trans. Commun., vol. 56, no. 9, pp. 1498-1510, Sep. 2008.
[14] H.-M. Chen, W.-C. Chen and C.-D. Chung, “Spectrally precoded OFDM and OFDMA with cyclic pre x and unconstrained guard ratios,” IEEE Trans. Wireless Commun., vol. 10, no. 5, pp. 1416-1427, May 2011.
[15] H.-M. Chen and C.-D. Chung, “Asymptotic spectral behavior of specrally precoded OFDM signal with arbitrary input statistics,” IEEE Commun. Lett., vol. 13, no. 5, pp. 324-326, May 2009.
[16] J. van de Beek, “Orthogonal multiplexing in a subspace of frequency well-localized signals,” IEEE Commun. Lett., vol. 14, no. 10, pp. 882-884, Oct. 2010.
[17] I. Cosovic, S. Brandes, and M. Schnell, “Subcarrier weighting: A method for sidelobe suppression in OFDM systems,” IEEE Commun. Lett., vol. 10, no. 6, pp. 444-446, Jun. 2006.
[18] A. Tom, A. ﹐ Sahin, and H. Arslan, “Mask compliant precoder for OFDM spectrum shaping, IEEE Commun. Lett., vol. 17, no. 3, pp. 447-450, Mar. 2013.
[19] J. van de Beek and F. Berggren, “N-continuous OFDM,” IEEE Commun. Lett., vol. 13, no. 1, pp. 1-3, Jan. 2009.
[20] S. Brandes, I. Cosovic, and M. Schnell, “Reduction of out-of-band radiation in OFDM systems by insertion of cancellation carriers,” IEEE Commun. Lett., vol. 10, no. 6, pp. 420-422, Jun. 2006.
[21] J. van de Beek and F. Berggren, “Out-of-band power suppression in OFDM,” IEEE Commun. Lett., vol. 12, no. 9, pp. 609-611, Sep. 2008.
[22] M. Ma, X. Huang, B. Jiao, and Y. J. Guo, “Optimal orthogonal precoding for power leakage suppression in DFT-based systems,” IEEE Trans. Commun., vol. 59, no. 3, pp. 844-853, Mar. 2011.
[23] J. Zhang, X. Huang, A. Cantoni, and Y. J. Guo, “Sidelobe suppression with orthogonal projection for multicarrier systems,” IEEE Trans. Commun., vol. 60, no. 2, pp. 589-599, Feb. 2012.
[24] L. Wei and C. Schlegel, “Synchronization requirements for multi-user OFDM on satellite mobile and two-path Rayleigh fading channels,” IEEE Trans. Commun., vol. 43, no. 2/3/4, pp. 887-895, Feb./Mar./Apr. 1995.
[25] M. Faulkner, “The effect of ltering on the performance of OFDM systems,” IEEE Trans. Veh. Technol., vol. 49, no. 5, pp. 1877-1884, Sep. 2000.
[26] T. Weiss, J. Hillenbrand, A. Krohn, and F. Jondral, “Mutual interference in OFDM based spectrum pooling systems,” in Proc. IEEE Veh. Technol. Conf., May 2004.
[27] IEEE 802.11-2012, IEEE Standard for Information Technology–Telecommunications and Information Exchange Between Systems Local and Metropolitan Area Networks–Specific Requirements Part 11: Wireless LAN Medium Access Control (MAC) and Physical Layer (PHY) Speci cations, Mar. 2012.
[28] IEEE 802.16-2009, IEEE Standard for Local and Metropolitan Area Networks Part 16: Air Interface for Broadband Wireless Access Systems, May 2009.
[29] IEEE 802.20-2008, IEEE Standard for Local and Metropolitan Area Networks Part 20: Air Interface for Mobile Broadband Wireless Access Systems Supporting Vehicular Mobility–Physical and Media Access Control Layer Speci cation, Aug. 2008.
[30] C. R. Stevenson, G. Chouinard, Z. Lei, W. Hu and S. J. Shellhammer, “IEEE 802.22: The first cognitive radio wireless regional area network standard,” IEEE Commun. Mag., vol. 47, no. 1, pp.130-138, Jan. 2009.
[31] I. S. Gradshteyn and I. M. Ryzhik, Table of Integrals, Series, and Products, 6th ed. New York: Academic Press, 2000.
[32] J. G. Proakis, Digital Communications, 5th ed. New York: McGraw-Hill, 2008.
[33] R. A. Horn and C. R. Johnson, Matrix Analysis. New York: Cambridge University Press, 1985.
[34] W. R. Bennett, Introduction to Signal Transmission. New York: McGraw Hill, 1970.
[35] B. O’Hara and A. Petrick, IEEE 802.11 Handbook: A Designer’s Companion. New York: IEEE Press, 1999.