本論文模擬一個應用於DVB-T數位電視地面廣播系統之OFDM數位調變技術。從中討論OFDM數位調變技術的發展與演進，並對於OFDM中各種關鍵技術進行研討。且藉由Matlab軟體的輔助，來模擬訊號完整的傳送過程。最後再討論在不同的通道估測技術(LMS、pilot data及Transform)，相對於傳統所使用之LS最小平方法所得到之更佳BER performance。
模擬結果顯示LMS於step size為0.1時相對於LS可以降低約20%BER；有使用pilot data之LS通道估測也比沒有使用pilot data的LS通道估測降低了約20%BER；而在發射端與接收端間有相對速度的情況下，因為有著Doppler Spread的影響，使用Transform Domain作為通道估測技術也比LS降低了約20%BER。

In the thesis, I simulate the entire OFDM modulation technology applied in DVB-T system. I start from the development of OFDM and focus on studying the key techniques. I’ll simulate the performance of OFDM system with Matlab, and discuss different channel estimation method including LMS, pilot data and Transform, compare with LS for the better BER.
The simulated result is that all the channel estimation methods I used reduce 20% BER at the same SNR, including the LMS with step size 0.1, adding pilot data in LS and Transform Domain for the Doppler Spread.

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