在第三代行動通訊系統係採用分碼多工接取(Code Division Multiple Access, CDMA)技術，可提供比分頻多工接取(Frequency Division Multiple Access, FDMA)與分時多工接取(Time Division multiple Access)系統更高的系統容量。不過對於高速傳輸的環境，通道的多路徑衰減與用戶間的非完全正交展頻碼，就會造成嚴重的符碼間干擾(Intersymbol Interference, ISI)以及多工接取干擾(Multiple Access Interference, MAI)。在另一方面，近來多載波調變技術被廣泛的使用於通訊系統，例如無線區域網路IEEE 802.11a、IEEE 802.11g等，原因在於多載波調變技術較能對抗多路徑衰減的影響，所以結合CDMA與多載波調變技術，可同時具備CDMA技術的多用戶接取能力與多載波調變技術的抗通道多路徑衰減能力等等，目前已有許多這種接取技術，其中多載波分碼多工(Multi-Carrier Code Division Multiple Access, MC-CDMA)[1]技術被公認為是後第三代行動通訊(Beyond 3G, B3G)系統中最可行的下鏈(downlink)技術。在這篇論文中，在接收端單一天線情況下，就多載波分碼多工接取(Multi-Carrier Code Division Multiple Access, MC-CDMA)結合空時方塊編碼(Space-time Block Coding, STBC)技術於下鏈(downlink)傳輸提出了一種新的盲蔽空時解碼(Blind Space-time Decoding, BSTD)演算法。
我們提出的盲蔽空時解碼演算法，基本上包含祁等人提出之快速峰度最大化演算法(Fast Kurtosis Maximization Algorithm, FKMA)與盲蔽最大比值合併(Blind Maximum Ratio Combining, BMRC)演算法。此盲蔽空時解碼演算法本身為一疊代演算法具有與快速峰度最大化演算法有相同之超指數(super-exponential)的收斂速率。更進一步，我們將提出的盲蔽空時解碼演算法擴充到多根接收天線，以獲得空間分集(space diversity)的增益。最後，以一些模擬結果來證實提出的盲蔽空時解碼演算法的效能。

In this thesis, a novel blind space-time decoding (BSTD) algorithm is proposed for the down-link of a space-time coded multicarrier CDMA (ST-MC-CDMA) system with single receive antenna used. The proposed BSTD algorithm, which basically consists of Chi et. al.’s fast kurtosis maximization algorithm (FKMA) and blind maximum ratio combining (BMRC) algorithm, is an iterative algorithm with su-per-exponential convergence rate as the FKMA. Furthermore, the proposed BSTD algorithm is extended to the case of multiple receive antennas for space diversity gain. Finally, some simulation results are presented to support the efficacy of the proposed BSTD algorithm.

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