正交分頻多工技術是利用正交的頻率通道來做高速率的資料無線傳輸，可以有效的抵抗多重路徑干擾，目前已成為通訊系統的關鍵技術，例如數位音訊廣播、數位視訊廣播和數位高畫質電視。但是，當正交分頻多工系統使用在無線行動通訊上時，用戶的移動會使得系統中各個子載波失去彼此之間的正交性，產生載波的互相干擾，造成錯誤地板效應。為了解決這個問題，我們根據對載波干擾的功率分佈分析，將因子圖及和積演算法應用到正交分頻多工系統中，藉由子載波與收到訊號之間的訊息傳遞，得到每個子載波上，訊號數值的事後機率，並將事後機率中，最大的值視為解調出來的訊號。在解調後，我們更進一步的將偵測後的信號回饋及剩餘干擾消除，再次利用因子圖來偵測信號，來得到一組更加準確的信號。由模擬結果可以發現，我們所提出的方法在雙重選擇性通道環境中的位元錯誤率接近於匹配濾波器極限。另外，在通道量測的部份，基於領航訊號愈多，量測到的通道會愈準備的想法，我們反覆的利用偵測後的訊號，將其當成是領航訊號，轉到時域做濾除雜訊及干擾的動作，使量測到的通道更為準確，再將測得通道與信號回饋及剩餘干擾消除機制做結合，增加解調訊號的精準度。由模擬結果發現，我們的方法，比其它的通道量測方法在位元錯誤率的表現好。

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