為了消除在正交分頻多重進接系統中，由於載波頻率誤差所造成之多用戶間的干擾，在這裡提出一個連續干擾消除的架構。這個架構是改善先前提出利用迴旋積分來抑制載波誤差造成的效應。將這篇論文所提出的方法，與先前的平行干擾消除的架構做比較，當系統中有K個使用者時，此連續干擾消除架構進行兩次遞迴後的效能，比平行干擾消除架構的效能好，而且系統複雜度只有平行干擾消除架構的1/2K而已，大幅度的降低硬體複雜度。在這篇論文中，也提出利用一些近似後，硬體複雜度能得到更進一步的精簡。

A successive interference cancellation (SIC) structure is proposed for multiuser interference cancellation (MUI) due to carrier frequency offsets (CFOs) in the uplink of orthogonal frequency division multiple access (OFDMA) systems. The proposed architecture adopts a circular convolution to suppress the impacts caused by CFOs. This paper demonstrates that, with 2 iterations, the SIC has better performance than that of the parallel interference cancellation (PIC), but system complexity is only 1/2K, where K is the number of users in the uplink of OFDMA system. This study also shows that system complexity can be significantly reduced if proper approximation is made.

Chapter 1 Introduction 1
Chapter 2 System Model 5
2.1 OFDM System Model 5
2.2 OFDMA System Model 8
Chapter 3 Previous Carrier Frequency Offsets Compensation Schemes 13
3.1 The Carrier Frequency Offsets Compensation Scheme in Time Domain 13
3.2 The Carrier Frequency Offsets Compensation Scheme in Frequency Domain 15
3.2.1 Choi et al. scheme 15
3.2.2 Huang and Letaiefs’ scheme 17
Chapter 4 The Proposed Successive Interference Cancellation Architecture 20
4.1 The Initiation Stage 21
4.2 The Detection Stage 22
4.3 The Interference Regeneration Stage 24
Chapter 5 Performance Analyses and Simulation Result 26
5.1 Analysis of Signal-to-Interference Ratio 26
5.2 Analysis of Complexity 31
5.3 Simulation Results 32
Chapter 6 Conclusions and Future Work 36
6.1 Conclusion 36
6.2 Future Work 36
REFERENCES 38

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