在第三代無線行動通訊中，由於多使用者的多重接取干擾及多路徑延遲造成的符碼間干擾會限制了單一網路中多使用者的容量，影響傳輸通訊的品質造成系統效能大幅下降。並且在非半靜態的多路徑環境中，多天線之分碼多工接取系統會因為傳遞延遲造成展頻碼失去正交性而造成相互干擾。為了降低在非半靜態通道下的解碼複雜度並且克服多路徑的衰弱，本論文提出平行處理之耙型接收器還原具有正交循環特性的時空碼並且配合多路徑干擾消除器來提升訊號強度。
本系統之設計理念是結合所提出之解碼架構與M-sequence低交相關的特性分離因多天線空間分集所造成的多路徑混波信號，並利用耙型接收器時間分集的方式克服多重路徑效應造成的訊號時間消散以得到不同路徑的最大分集增益。在這之後，我們利用提出的多路徑干擾消除機制重建每根傳送天線上的傳輸訊號副本，在最大比例合成器前進行符碼間的干擾消除。我們將分析不同傳輸率和分集增益的傳輸矩陣，並且系統錯誤率一併在本論文中討論。
根據數值分析與模擬結果顯示，我們所提出之系統架構在多路徑環境且非半靜態的通道中，利用簡單且低複雜度的最大相似法則解碼，相較於傳統所採用的時空區塊碼於單一耙型接收器的多天線分碼系統，可以得到更優越的效能而且更適合用於無線行動通訊。

In the 3rd generation mobile communication system, as a result of Multiple Access Interference (MAI) caused by multi-users and inter-symbol interference (ISI) due to multipath propagation delay, those interferences limit the capacity of multiple users in the cellular system and affect the transmission quality of communication, decreasing the system performance seriously. Besides, the orthogonal condition of spreading sequences in MIMO-CDMA system is destroyed and cause interference in multipath environment and non-quasi static channel. So as to decrease the complexity of system and overcome the multipath fading, the parallel rake receivers to despread orthogonal- and cyclic- inherent space-time code and multipath interference cancellation to enhance the signal signature are proposed in this thesis.
The system design is a combination of our proposed decoding structure and using the correlation characteristic of M-sequence to separate multipath signals caused by spatial diversity in MIMO system. To overcome the time dispersion of the transmitted signal due to multipath effect, we utilize rake receivers with time diversity and achieve the maximal diversity gain from the independent multipath component. After that, we use the proposed multipath interference mechanism to reconstruct the several replicas of the same information signal which is transmitted over transmit antennas, eliminating the ISI before maximum ratio combining. We analyze the different transmission rate and diversity order for different transmit antennas. Furthermore, the exact error probability of the proposed scheme is also derived.
Mathematical analysis and simulation results show that the proposed scheme in multipath environment over non-quasi static channel, it can be decoded by a significant low complexity ML decoder. Comparing to conventional STBC with single rake receiver in MIMO-CDMA scheme, it obtains the better system performance and suitable to use in the wireless mobile communication.

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