在正交分頻多工系統中，多重路徑時變移動通道會破壞子載波間的正交性，造成子載波間干擾。為了消除子載波間干擾，在本篇論文中我們提出了一個以疊代的方式，配合決策迴授的子載波干擾消除等化器來消除子載波間的干擾。因為計算子載波干擾消除等化器的係數需要知道通道脈衝響應參數，因此我們研究以延伸型卡曼濾波器作為通道估計的方法，並使用迴歸模型來預測通道脈衝響應。此外，我們考慮通道平滑化的方法，來達成更好的通道估計效能。最後模擬結果顯示，本論文所提出新的系統在移動無線通道中，可以較過去的方法更有效地消除子載波間干擾的效應。

In applying the orthogonal frequency division multiplexing technology the multipath time-varying mobile channels can lead to intercarrier interference (ICI) among subcarriers. To eliminate the ICI, we proposed a new iterative algorithm with the decision feedback ICI cancellation (DFIC) equalizer in this thesis. Since the coefficients of the DFIC equalizer have to be calculated relying on the knowledge of the channel impulse response (CIR), we employ the extended Kalman filter for channel estimation and the regression model for CIR prediction. In addition, we can invoke a smoothing method to enhance the performance of channel estimation. Simulation results show that the proposed algorithm is more effective than previous works to mitigate the ICI effect in mobile wireless OFDM channels.

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