在本論文中，我們將使用分時多工雙路徑傳輸之相位旋轉共軛消除技術(phase-rotated conjugate cancellation；PRCC)應用至基於離散哈特利轉換(discrete Hartley transform；DHT)的濾波器組多載波(filter bank multicarrier；FBMC)系統，以減輕因載波頻率偏移(carrier frequency offset；CFO)所造成的載波間干擾(intercarrier interference；ICI)。本論文之相位旋轉運算乃在接收端執行，而非如傳統的PRCC作法是在傳送端執行，故接收端不須回傳CFO估測值至傳送端以決定適合的相位旋轉值。為開發此一DHT-FBMC系統的PRCC時域分集增益，我們提出一適應性接收機設計以強化資料偵測效能，其中每一路徑的接收訊號經過一相位旋轉器和一等化器處理後，再進行分集結合；我們根據初步的CFO估測值，設定相位旋轉初始值，並利用區塊式最小均方差演算法持續更新相位旋轉值以逼近最佳解。此一基於PRCC的適應接收機設計使DHT-FBMC系統能夠有效克服實際應用中的ICI/CFO問題並進而追蹤CFO的變化。電腦模擬結果顯示，在時變CFO的環境下，我們針對DHT-FBMC系統所提出之適應性PRCC技術比傳統的PRCC作法具有較佳的位元錯誤率效能，且CFO值的變化範圍越大，效能改善越為明顯。

In this thesis, we apply the phase-rotated conjugate cancellation (PRCC) technique with two-path transmission in a time-division multiplexing manner to a filter bank multicarrier (FBMC) system based on the discrete Hartley transform (DHT) to mitigate intercarrier interference (ICI) due to carrier frequency offsets (CFOs). The phase rotation is performed at the receiver, rather than at the transmitter as in the conventional PRCC method, so there is no need to feed CFO estimates from the receiver back to the transmitter to determine appropriate phase rotations. To exploit the time diversity gain of PRCC in the DHT-FBMC system, an adaptive receiver design is proposed that employs a phase-rotation unit along with an equalizer for each of the two paths and a diversity combiner to enhance data detection. With a rough CFO estimate at the receiver, an initial phase rotation is set accordingly and then updated iteratively by using the normalized block least mean-squared algorithm to approach the optimal solution. Such an PRCC-based adaptive receiver design enables the DHT-FBMC system to overcome the ICI/CFO problem effectively and to track the CFO variations well in practical applications. Computer simulation results demonstrate that the proposed scheme achieves better bit-error-rate performance than the conventional PRCC method for the DHT-FBMC system under a time-varying CFO scenario, where the improvement becomes more obvious as the range of CFO variations increases.

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