在無線通訊領域中，合作式通訊在近幾年受到許多討論，因為在多輸入多輸出系統上，如果使用增加天線來提升系統傳輸量以及降低傳輸錯誤率，會有其困難性存在，因為通訊設備越做越小，要容納那麼多天線，空間可能不足，因此合作式通訊，這種分散式天線設計，解決了這一問題，利用中繼點的幫助，相較於多輸入多輸出系統，能降低硬體設計上的複雜度，並且降低硬體成本。本論文在中繼端是使用解碼後轉傳，並且在接收端研究使用有效的方法把訊號結合起來。在通道估測以及傳遞方面，我們會插入pilot，當作基於Karhunen-Loève Expnsion (KLE)提出的通道估計方法所需要的重建通道響應的係數,並且會利用高斯量化,減少通道係數傳遞的誤差。

In the field of wireless communication, cooperative communication has many discussion in recent years. On the Multiple-Input Multiple-Output(MIMO) system, you increase the number of antenna to increase channel capacity and reduce bit error rate, there will be difficult, because the communication equipment is getting smaller and smaller, and it needs to accommodate so many antennas, the space may be insufficient. Therefore cooperative communication’s distributed antenna design solves this problem. With the help of relay points, compared with MIMO systems, hardware design complexity can be reduced and hardware costs can be reduced. This thesis uses decode-and-forward at the relay, and studies to use valid methods to combine the signals at the receiving end.In terms of channel estimation and delivery, we will insert pilot as the coefficient of the reconstruction channel response needed, channel estimation method is based on the Karhunen-Loève Expnsion (KLE), and then, we use Gaussian quantization to reduce the error of channel coefficient transmission.

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