上行預編碼通用濾波多載波系統之領航訊號能量分配設計

Abstract

在這篇論文中，我們提出在預編碼通用濾波多載波系統下引示信號能量分配方法來降低最小均方根通道估測誤差。通用濾波多載波系統是一個多載波傳送系統來克服正交分頻多工系統中載波間干擾的問題。通用濾波多載波系統對一整個資源區塊濾波來降低對旁邊資源區塊的干擾。在有載波頻率偏移環境下，通用濾波多載波系統跟正交分頻多工系統相比有較好的表現，然而通用濾波多載波系統會增加通道長度由於對一整個資源區塊濾波。基於以上性質，我們提出引示信號能量分配方法來降低通道估測誤差。而模擬結果也顯示我們提出的引示信號能量分配方法的確降低了通道估測誤差。

In this thesis, we study the minimum mean square error(MMSE) channel estimation algorithm and design the pilot signal power allocation to reduce channel estimation error in precoded universal-filtered multi-carrier (UFMC) system. UFMC system is a multi-carrier transmission scheme to overcome the problem of inter-carrier interference (ICI) in orthogonal frequency division multiplexing (OFDM) systems. In UFMC scheme, a filtering operation is applied to a group of consecutive subcarriers in order to reduce out-of-band sidelobe levels and subsequently minimize the potential ICI between adjacent users in case of asynchronous transmissions. Despite the fact that UFMC have better performance than OFDM in carrier frequency offset environment, UFMC have lengthen channel taps because of the filter. Based on this properity, we propose a method about pilot signal power allocation to reduce channel estimation error in precoded UFMC system. And simulation result shows that the pilot signal power allocation we proposed really reduce the channel estimation error.