由於合作式通訊能獲得合作式分集增益, 所以近年來已受到許多之矚目。然而當兩端點藉由多個中繼點作單向傳輸時, 獲得完美的通道資訊是困難的, 所以中繼點須估測它們前後之通道, 以便於放大資料至終點端。我們研究通道估測誤差所帶來的影響, 以及設計一線性最小化均方差估測器來估測通道,我們也考慮了多中繼點架構, 以便於在傳輸資料時提供訓練及傳輸之使用。在分析上我們提出了訊雜比溝差率, 中斷機率, 以及位元錯誤率。從模擬圖中能顯示, 當使用較多個中繼點作中繼時, 此一架構對於所有放大傳送之方法, 能減緩其通道估測誤差所帶來的影響。

Cooperative communications have received much attention recently, due to its ability to attain cooperation diversity. But when two nodes communicate via relays, it is difficult to get the perfect
channel information, so relays must estimate their forward channel and backward channel
in order to amplify the data to the destination. We investigate the effect of channel estimation
error, and design the LMMSE estimator to estimate the channels, and also we consider the
multi-relays to assist the whole system for training and data transmission. We propose the
SNR gap ratio, outage probability, and the BER simulations for the analysis. Simulation shows
that when using multi-relays, it can mitigate the effect of channel estimation errors in all of
the amplify-and-forward (AF) scenarios.

Chapter 1: Introduction-p.1
Chapter 2: System model and theory basis-p.2
Chapter 2.1:System model-p.2
Chapter 2.2:Channel estimation in the training phase p.3
Chapter 2.3:Data transmission-p.4
Chapter 2.4:Find the variance of channel estimation error α-p.6
Chapter 3:Analysis of SNR gap ratio-p.8
Chapter 3.1:Fixed gain relaying-p.8
Chapter 3.2:Variable gain relaying-p.10
Chapter 4:Outage probability on channel
estimation error-p.13
Chapter 4.1:Fixed gain relaying-p.13
Chapter 4.2:Variable gain relaying-p.14
Chapter 5:Simulation results-p.16
Chapter 6:Conclusion-p.26
Chapter 7:Appendix-p.27
Reference: p.30

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