在未來的世代，無線通訊系統被要求具有高速的傳輸能力以滿足未來的影像、音樂下載等多媒體服務需求。 然而高速的傳輸通常伴隨嚴重的多路徑干擾
(multipath effect )，這也造成了通道呈現嚴重頻譜不平坦。 傳統解決多路經的方式是藉由時間上的濾波器來等化通道，此方法會伴隨著通道多路徑數目而大大增加複雜性和硬體上的成本。
在本論文中，將會介紹單載波的頻域等化器(SC-FDE)，此方法相對於傳統的時間上的濾波器有較簡單的複雜度，且我們也將介紹回授機制(decision feedback)等化方式應用在此系統。

Nowadays wireless wideband communication systems provide high date rates transmission for satisfying the need of audio and video services. However, high data rate signals of a wideband single-carrier system cause serious multipath effects which result in the frequency selective fading of signals. The conventional way of solving the multipath effects resorts to the time-domain filter to equalize the channel.
For the conventional time-domain equalization, the filter complexity increases with the number of channel multiple paths.

In this thesis, we study the frequency-domain equalization, which in general has lower complexity than time-domain equalization. We also apply the decision feedback approach in our system.

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