A Study of Noncoherent/Differential Detection in Cooperative Communications

[[abstract]]在合作式通訊系統(Cooperative Communication System)中，解調後轉傳協定(Decode-and-Forward Protocol)為轉傳端(Relay)最常使用之轉傳協定之一。本論文提出在接收端完全的不知道傳送通道的狀況底下並且在轉傳端與目的端皆使用非同調解調之合作式通訊系統架構，而在目的端分別使用非同調等增益組合器(Noncoherent Equal Gain Combiner， EGC)和非同調選擇分集(Noncoherent Selection Combining , SC)來做解調。在本論文中我們亦討論於合作式通訊系統中應用於不同的轉傳端個數和不同的通道環境下，透過多樣性的效果以提升系統效能，此方法將能更貼近現實的情況。最後，在模擬結果中也將顯示此系統之效能。[[abstract]]In cooperative communications, the decode-and-forward (DF) protocol is one of the most important protocols for use in relay. In this thesis, we discuss both the relay nodes and destination node use noncoherent detection technologies without channel state information at the receiving sides. We use noncoherent equal gain combining and noncoherent selection combining for detection at the destination. In addition, we discuss this DF scenario with different numbers of relays under different channel conditions. This cooperative diversity technique results in better performance. Finally, simulations are performed to show the effectiveness of the proposed method.[[note]]碩