DVB-T系統之通道估測方法設計與模擬

Design and Simulation of Channel Estimation Methods in DVB-T Systems

徐永吉(Yung-Chi Hsu)

指導教授 ： 陳永芳

國立中央大學/資訊電機學院/通訊工程研究所碩士在職專班/碩士(2007年)

摘要

在本論文中提出一個可以用來提高數位電視廣播(DVB-T)的通道估測效能的方法。數位電視廣播(DVB-T)通道的估測主要分成二個步驟，領航信號(Pilot signal)的估測及通道係數(Channel coefficient)的內插(interpolation)，內插的準確性對通道估測的效能影響很大，同時和訊雜比(Signal-to-Noise Ratio)相關，我們使用OFDM符元(Symbols)通道係數結合的方法，複製估測的通道係數到一個OFDM符元相同子載波上，和兩次一維內插相比，我們提出的方法沒有延遲OFDM符碼時間同時節省六個OFDM符碼記憶空間及一次內插。和頻域線性內插相比，電腦的模擬證明，我們所提出的方法可以有效的提高估測效能。

關鍵字

通道估測 ； 數位電視

並列摘要

This thesis proposes a method to improve the channel-estimation performance in Digital Video Broadcasting-Terrestrial (DVB-T) Systems. In DVB-T, the channel estimation is carried out through two processes of pilot signal estimation and channel coefficient interpolation, and thus the performance of the channel estimation is seriously affected by the accuracy of the interpolation. Since the accuracy of the interpolation depends on signal-to-noise ratio, we use symbols channel coefficients combining method. The method is to copy the estimated channel coefficients corresponding to the same subcarriers in other OFDM symbols. This method has the advantages of no OFDM symbol time delay and save six OFDM symbol memory and one interpolation when it is compared with two one-dimension interpolation schemes. The computer simulation results show that the proposed method improves the estimation performance when it is compared with the frequency-domain linear interpolation.

並列關鍵字

channel estimation ； dvb-t

參考文獻

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