在正交分頻多工(OFDM)系統下，空頻區塊碼(SFBC)因其能獲得的空間和頻率分集而被廣泛採用，但正交分頻多工卻對載波頻率偏移(CFO)非常敏感，這會造成嚴重的載波間頻率干擾(ICI)，進而影響系統的性能。在這篇論文中，我們為Alamouti編碼的SFBC-OFDM合作式中繼系統提出了一種低複雜度的基於部分平行干擾消除(partial PIC)的接收機，它包括共同CFO補償方法，SFBC解碼器和一個迭代partial PIC模塊組成。由於發送天線分散式特性，我們先將接收到的訊號補償一個共同的頻率偏差值。接下來我們採用了一個改進的SFBC解碼器來解調訊號，再由解出的訊號重建出ICI，並進行partial PIC。在此基礎上，我們討論了引進共軛傳輸方法後系統的改善程度。經由模擬結果顯示，我們提出的基於PPIC的接收機相對於其它相關方法能夠獲得更好的性能表現。

Space frequency block codes (SFBC) have been widely adopted with orthogonal frequency division multiplexing (OFDM) to achieve both spatial and frequency diversity; however, OFDM is very sensitive to carrier frequency offset (CFO), which would cause intercarrier interference (ICI) and degrade the system performance severely. In this thesis, we propose a low-complexity partial parallel interference cancellation (PIC) based receiver with common CFO compensation, modified SFBC decoding, and iterative partial PIC for Alamouti coded SFBC-OFDM cooperative relay systems. For the proposed receiver, the received signal is first compensated by a common CFO value to mitigate the effect of different CFOs from the distributed relays, and the result is processed by a modified SFBC decoder. The decoded data is subsequently fed back to reconstruct the ICI for use in the developed partial PIC procedure. Also, we extend the proposed receiver design to SFBC-OFDM cooperative relay systems with conjugate transmission for achieving time diversity. Simulation results demonstrate that the proposed partial PIC based receiver provides significant performance improvement over a previous related work.

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