軟體無線電數位電視廣播接收器通道估測的改善

Improved Channel Estimation for PC-Based Software Radio DVB-T Receiver

李彥廷(Yan-Ting Li)

指導教授 ： 曾恕銘 ； 張立中

國立臺北科技大學/電資學院/電腦與通訊研究所/碩士(2008年)

摘要

在本文中，一種改善離散傅立葉轉換(DFT)通道估測運用以電腦為基礎的數位電視廣播接收器測試平台被提出。適應性的低通濾波器被提出來抑制頻帶以外的雜訊。當移動的速度變快時，它的通過頻帶變的更寬。適應性低通濾波器可以自動選擇通過的頻帶。我們也用中值濾波器來減少時域的脈衝雜訊。實地測試的結果顯示被提議的系統勝過以前線性內插法和以傅立葉轉換為基礎用門檻的通道估測系統。

關鍵字

離散傅立葉轉換 ； 通道估測 ； 數位電視廣播 ； 低通濾波器 ； 中值濾波器

並列摘要

In the paper, an improved discrete Fourier transform (DFT)-based channel estimation for a PC-based software DVB-T receiver testbed is proposed. An adaptive low pass filter is proposed to suppress out-of band noise. Its passband get wider when higher moving speed. It can select passband automatically. We also reduce the impulse noise in time domain by the median filter. The field test results show that the proposed scheme outperforms the previous linear interpolation and DFT-based channel estimation with threshold schemes.

並列關鍵字

DVB-T ； DFT ； channel estimation ； LPF ； median filter

參考文獻

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