在快速時變通道下，正交分頻多工系統會產生子頻帶間干擾的問題，它使得位元錯誤率不會因為提高訊雜比而下降，此問題也發生在使用頻域等化的單載波區塊傳輸系統。子頻帶間干擾的問題在近幾年逐漸被探討，雖然提出的方法都是在正交分頻多工系統上，但同樣能適用在單載波區塊傳輸系統。其產生的原因有主要兩種，載波頻率偏移以及快速時變通道。在本論文中我們會針對第二種原因加以探討。
在此論文中，我們引進現有單載波區塊傳輸系統的子頻帶間干擾消除演算法，將之套入單載波區塊傳輸系統，為了要克服殘留子頻道間干擾的影響，我們在偵測時使用K-best演算法來避免放大殘留子頻帶間干擾，論文最後模擬的結果證明我們成功克服殘留子頻帶間干擾造成的影響，並與MMSE作比較。

In fast time-varying channel, the orthogonal frequency division multiplexing (OFDM) system suffers from inter-subchannel interference(ICI). The problem of ICI also occurs in the single-carrier block transmission(SCBT) with frequency-domain equalization(FDE) system. Though the ICI problem has caused much concern for the OFDM system, some of these algorithms are also suitable for the SC-FDE system. The effect of ICI may come from carrier frequency shift or the high-mobility (fast time-varying) channel.
In this thesis, we consider an ICI self-reduction algorithm for the SC-FDE system. In order to prevent the enhancement of residual ICI after the ICI self-reduction, we apply the K-Best algorithm in detection to search for the near maximum-likelihood (ML) solution. With the detection based on K-best algorithm, we can avoid the residual ICI enhancement. We compare our results with another method that can also reduce the enhancement of residual ICI, and the simulation results validate our method.

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