相對於傳統的合作式通訊，連續中繼傳輸是一個有效降低多工容量損失的傳輸模式。因為傳統的合作式通訊，需要花費兩個時槽才能傳輸一筆資料，造成50%的多工容量損失，而連續中繼傳輸因為多個中繼點輪流使用，因此改善了此項缺點，將多工容量提升至N/(N+1)。

但是連續中繼傳輸有一個很大的問題就是中繼間干擾，這個現象會嚴重的影響整體系統的效能。因此我們提出一個新的傳輸模式，源節點使用階層式調變，並且設計資料傳輸的方式，使得中繼間干擾的影響可以消除，因此提升整體系統的效能。

而本論文中，我們使用位元錯誤率來跟別人的系統比較，能發現我們所提出的方法更能對抗中繼間干擾所造成的影響。

Relative to the traditional cooperative communication, successive relaying offers a way to reduce the multiplexing loss. The traditional cooperative communication takes two time slots to transmit a data, it results in 50% multiplexing loss. However successive relaying use two relays in turn, it can improve the drawback of the multiplexing loss to N/(N+1) .

Unfortunately successive relaying transmission has a serious problem that is the inter-relay interference. This phenomenon will seriously affect the entire system performance. Hence we proposed a novel transmission protocol, the source used hierarchical modulation, and design a new sort of data transmission, that can eliminate inter-relay interference and improving system performance.

In this paper, we use bits error rate to compare with other protocol (i.e. classic successive relaying), and our protocol is more effective to confront inter-relay interference.

口試委員會審定書 #
致謝 i
中文摘要 ii
ABSTRACT iii
CONTENTS iv
LIST OF FIGURES v
LIST OF TABLES vii

Chapter 1 Introduction 1
Chapter 2 Preliminaries 4
2.1 Hierarchical Modulation 4
2.2 Classic Successive Relaying 5
Chapter 3 Hierarchical Modulation-based Successive Relaying Protocols 8
3.1 Two Relays 8
3.2 Three Relays 16
3.3 Decoding Algorithm at Destination 21
Chapter 4 Simulation Results 27
4.1 Different Signal to Interference Ratio 28
4.2 Average Time Slot of Relay Transmits First Error 30
4.3 Throughput 32
4.4 Different Modulation Parameter 33
Chapter 5 Conclusions 35
Appendix 36
REFERENCES 38

[1] A. Sendonaris, E. Erkip, and B. Aazhang, “User cooperative diversity-part Ⅰ and Ⅱ,” IEEE Trans. Commun., vol. 51, no. 11, pp.1927-1938, Nov. 2003.
[2] J. N. Laneman, D. N. C. Tse, and G. W. Wornell, “Cooperative diversity in wireless networks: Efficient protocols and outage behavior,” IEEE Trans. Inform. Theory, vol. 50, no. 12, pp.3062-3080, Dec. 2004.
[3] J. N. Laneman, and G. W. Wornell, “Distributed space-time-coded protocols for exploiting cooperative diversity in wireless networks,” IEEE Trans. Inform. Theory, vol. 49, pp.2415-2425, Oct. 2003.
[4] R. U. Nabar, et al. , “Fading relay channels: Performance limits and space-time signal design,” IEEE J. Sel. Areas Commun., vol. 22, no. 6, pp.1099-1109, Aug. 2004.
[5] Y. Hong, W. Huang, F. Chiu, and C. Kuo, “Cooperative communications in resource-constrained wireless networks,” IEEE Signal Processing Magazine, vol. 24, no. 3, pp. 47-57, 2007.
[6] K. Lee, L. Hanzo, and S. Samsung, “Resource-efficient wireless relaying protocols,” IEEE Wireless Communications, vol. 17, no. 2, pp.66-72, 2010.
[7] B. Rankov and A. Wittneben, “Spectral efficient protocols for half-duplex fading relay channels,” IEEE Journal on Selected Areas in Communications, vol. 25, no. 2, pp. 379-389, 2007.
[8] Y. Fan, C. Wang, J. Thompson, and H. Poor, “Recovering multiplexing loss through successive relaying using repetition coding,” IEEE transactions on wireless communications, vol. 6, no. 12, pp. 4484-4493, 2007.
[9] C. Wang, Y. Fan, I. Krikidis, J. S. Thompson, and H. V. Poor, “Superposition-coded concurrent decode-and-forward relaying,” IEEE International Symposium on Information Theory, pp. 2390-2394, 2008.
[10] J. Zhang, J. Cao, G. Yu, H. Zhuang, and Z. Luo, “A novel successive relaying protocol based on superposition coding,” IEEE International Conference on Communication Technology, pp. 1043-1046, 2010.
[11] Y. W. Hong, W. J. Huang, and C. C. Kuo, Cooperative Communications and Networking Technologies and System Design. Springer, 2010
[12] C. Wang, Y. Fan, J. S. Thompson, M. Skoglund, and H. V. Poor, “Superposition-repetition-coded successive decode-and-forward relaying with limited destination-relay feedback,” IEEE Wireless Communications and Networking Conference, pp. 1-6, 2010
[13] M. A. El-Gendi, M. M. Khairy, and O. A. Nasr, “Cooperative Multicasting Based on Superposition and Layered Coding,” IEEE GLOBECOM, pp. 1-5, 2011.
[14] Q. Y. Liau, and C. Y. Leow, “Study of Relay Position in Two-Path Successive Relaying with Interference Cancellation,” IEEE Asia Pacific Conference on Wireless and Mobile, pp. 254 - 259, Aug. 2014.