濾波式多載波傳輸系統之載波頻率偏移估測方法

Carrier Frequency Offset Estimation Method for Filtered Multitone Transmission System

黃士芳(Shih-Fang Huang)

指導教授 ： 魏學文

國立暨南國際大學/科技學院/電機工程學系/碩士(2009年)

摘要

在無線多路徑快速衰減通道下，多載波調變(Multicarrier modulation)傳輸系統對於載波頻率和時序的錯誤是相當敏感的，因此如何估測出載波頻率偏移(Carrier frequency offset，CFO)是本文主要的目的。本文針對FMT(Filtered multitone)傳輸系統之CFO估測方法，改良BLU(Best linear unbiased)方法的訓練符元Pattern，以提高其估測準確度。利用打散FMT Polyphase filter bank的係數相關性來設計訓練符元Pattern可以有效避免ISI(Intersymbol interference)對CFO估測的影響。模擬顯示，一個好的Training pattern設計可以大幅提高CFO估測準確度，尤其是在高速移動環境下。

關鍵字

FMT ； 濾波器組 ； 訓練符元設計 ； 載波頻率偏移 ； 最大概似法 ； 最佳線性不偏

並列摘要

In multipath fast fading wireless channel, multicarrier modulation transmission system is very sensitive to carrier frequency offset and timing offset, thus the purpose of this paper is to estimate the carrier frequency offset. In this paper, we use training symbol based on BLU (Best linear unbiased) method to improve CFO estimation accuracy for FMT (Filtered multitone) transmission system. It is shown that breaking up the correlation of the FMT Polyphase filter bank coefficient by designing the training symbol pattern can avoid the influence of ISI (Intersymbol interference) in the CFO estimation. Simulation shows that a good training pattern design can significantly increase the accuracy of CFO estimation, especially in the high-speed mobile environment.

並列關鍵字

FMT ； Filter bank ； Training symbol design ； CFO ； ML ； BLU

參考文獻

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