近年來多輸入-多輸出之正交分頻多工技術，已經被廣泛的應用在許多重要的數位通訊系統中。其中有關傳送端或接收端天線間通道彼此的相關性與偶和效應，也引起不少的注意與廣泛討論。 一般來說，由於傳送或接受端天線間彼此距離非常靠近，天線間彼此所產生的耦合效應不容被忽略。 本論文在慢速時變與多路徑通道環境下，就所謂無循環前置碼同時具有空間-時間區塊編碼之多輸入多輸出正交分頻多工系統的新式接收器架構探討上述天線間通道彼此的相關性與偶和效應對系統效能所造成的影響。 尤其是在不使用多餘冗員碼以移除符號間干擾的系統， 如何有效能改善接收器效能同時減少頻譜之浪費。本篇論文在多天線傳輸系統中採用空間與頻率資源在接收端結合斜面投影頻域決定迴授等化器，所謂的斜面投影，基本上為一種非交投影技術，此方法用來有效處理結構雜訊的問題 (例如：符號間干擾項)，因此我們將此方法用於消除接受端之符號間干擾與載波間干擾，並且在其傳輸天線通道間彼此相關性中，進一步透過電腦的模擬分析，觀察探討不同天線間距彼此所產生耦合現象的變化。

This thesis considers a multiple-input multiple-output (MIMO) orthogonal frequency division multiplexing (OFDM) or the MIMO-OFDM system framework, which includes the effect of channel correlation between the transmit antennas or the receive antennas. In practice the antenna spacing in the transmitter or the receiver is limited; the mutual coupling effects between array elements could not be ignored. We focus on the space-time block coded (ST-BC) MIMO-OFDM uplink transmission system, This thesis presents a receiver which is a framework of the MIMO-OFDM over under slowly-varying multipath channels, without using the cyclic-prefix (CP) to improve the spectral efficiency. To mitigate the penalty of CP-free in the ST-BC MIMO-OFDM system, in which the inter-block-interference (IBI) system may not be removed sufficiently, more complicated receiver should be developed to maintain the desired system performance. By it exploiting the spatial and frequency resources, the frequency-domain block-based decision-feedback equalizer (DFE) associated with the oblique projection (OB) technique has been proposed to dealing with this problem. The oblique projection (OB) is a non-orthogonal projection, and is very useful to alleviate the effect of structure noise issue (e.g., the IBI term). Computer simulation results are carried out to verify the impacts of channel correlation and mutual coupling between transmit and receive antennas.

論文審定書.........................................................................................................................................i
致謝..................................................................................................................................................ii
中文摘要...........................................................................................................................................iii
ABSTRACT.......................................................................................................................................iv
CONTENTS.......................................................................................................................................v
LIST OF FIGURES...........................................................................................................................vii
LIST OF TABLES..............................................................................................................................ix

CHAPTER 1
INTRODUCTION................................................................................................................................ 1
1.1 MOTIVATION AND BACKGROUND .............................................................................................. 1
1.2 CONTENT AND CONTRIBUTION OF THESIS................................................................................ 3

CHAPTER 2
REVIEW OF THE ST-BC MIMO-OFDM SYSTEMS............................................................................... 6
2.1 INTRODUCTION .......................................................................................................................... 6
2.2 SPACE-TIME BLOCK CODE ........................................................................................................ 7
2.3 ORTHOGONAL FREQUENCY DIVISION MULTIPLEXIN................................................................. 10
2.4 CP-BASED ST-BC MIMO OFDM SYSTEM ................................................................................... 12
2.5 CP-FREE ST-BC MIMO OFDM SYSTEM ..................................................................................... 17
2.5.1 EQUALIZATION BASED ON ISI/ICI SUPPRESSION SCHEME .................................................. 22
.
CHAPTER 3
DESIGN OF FREQUENCY DOMAIN EQUALIZER WITH OBLIQUE
PROJECTION FOR CP-FREE ST-BC MIMO-OFDM SYSTEM ............................................................. 26
3.1 INTRODUCTION ......................................................................................................................... 26
3.2 THE CONCEPTS OF PROJECTION OPERATOR ......................................................................... 28
3.3 FREQUENCY DOMAIN DECISION FEEDBACK EQUALIZER ASSOCIATED WITH OBLIQUE PROJECTION................................................................................................................................... 33

CHAPTER 4
THE EFFECTS OF ANTENNA MUTUAL COUPLING ........................................................................... 41
4.1 INTRODUCTION ......................................................................................................................... 41
4.2 CHANNEL CORRELATION SYSTEM MODEL ............................................................................... 42
4.3 IMPACT OF ANTENNA MUTUAL COUPLING ON CHANNEL CORRELATION ................................. 46
...
CHAPTER 5
COMPUTER SIMULATIONS ............................................................................................................. 52
5.1 INTRODUCTORY ....................................................................................................................... 52

CHAPTER 6
CONCLUSIONS ............................................................................................................................... 59

APPENDIX A.
DERIVATION OF QR-BASED OBLIQUE PROJECTOR ....................................................................... 60
.
APPENDIX B
LINEAR ZF EQUALIZER .................................................................................................................. 64

APPENDIX C
LINEAR MMSE EQUALIZER ............................................................................................................ 65

APPENDIX D
CORRELATION COEFFICIENT ......................................................................................................... 67

REFERENCES ................................................................................................................................ 70

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