為了克服多重存取干擾，多用戶檢測技術應運而生。然而最佳化與次佳化的檢測器在硬體實現時的複雜度太高，因此連續干擾消除(Successive Interference Cancellation, SIC) 檢測器由於在硬體實現上的簡易性，在近年來被廣泛的研究。其中之ㄧ的研究重點即是通道估測，而通道估測一定是不完美的，估計誤差在連續干擾消除接收器中會成為其他使用者的干擾，甚至造成錯誤傳延的現象。
在論文中，我們將以同步直接序列分碼多重存取(Direct Sequence Code Division Multiple Access, DS-CDMA)系統為基本之通訊架構，探討連續干擾消除接收器中的通道估測技術。我們將介紹眾所周知的估計子，包括最小平方估計子(Least-Squares Estimator, LSE)、最佳線性無偏估計子(Best Linear Unbiased Estimator, BLUE)、線性最小均方誤差估計子(Linear Minimum Mean Square Error Estimator, LMMSE)、以及純量卡門估計子(Scalar Kalman Estimator)。在通道估測時，我們除了純量模型之外也使用連續多個時間點的資料進行單一點的通道估測。之後我們對連續干擾消除接收器稍作改變，探討在多重存取干擾較小的去相關連續干擾消除(Decorrelator Based Successive Interference Cancellation, DBSIC)接收器以及最小均方誤差連續干擾消除(Minimum Mean Square Error- Successive Interference Cancellation, MMSE-SIC)接收器中上述估計子有何改變以及系統效能的變化，其中去相關連續干擾消除接收器即是傳統的連續干擾消除接收器加入去相關檢測器，而最小均方誤差連續干擾消除接收器則是加入最小均方誤差檢測器。最後提出模擬結果與結論。

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