近年來，隨著通訊科技不斷的研發與改進，在我們生活週遭所觸及的通訊產 品已經越來越多，而其帶來的便利性也不斷的在提升。因此，無論是有線通訊系 統或是無線通訊系統都還有相當之發揮空間，其涵蓋範圍小至區域網路，大至衛 星通訊，可說是時時刻刻都不斷的改善我們對通訊便利的需求。而現今人手一機 的現象，更凸顯了通訊科技對我們的重要性。隨著數位通訊系統完善的開發，傳 統的類比電視也自然的朝向數位的領域邁進。因此，我們針對歐規的數位地面電 視廣播系統做一深入的探討，希望能透過通訊系統的理論基礎及演算法的改進，
使DVB-T 系統達到性能的提升。
在本計畫中的第一年，我們首先針對DVB-T 系統的核心 OFDM 架構作一研 究，並專注DVB-T 標準中所採用的 2k 和 8k 之 FFT 方塊設計，透過數學演算法 的推導分析以及電路觀念的整合，設計出適當的 FFT 電路晶片。另外，我們探 討 OFDM 信號的同步問題，我們使用了數種同步估測演算法來估測信號到達的 時間延遲及頻率偏移量，並透過估測器性能的分析了解採用不同的演算法所得到 的優勢與缺點。
在接下來的研究中，我們將繼續探討在DVB-T 系統接收端之同步與等化器 的設計，期望能透過演算法的改善而提出一性能較佳的同步與等化器。最後並進 而整合基頻部分，完成OFDM 解調變器的晶片。
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