歐規的地面數位電視廣播系統(DVB-T)使用了正交分頻多工(OFDM)的技術，在無線傳輸的通道下能提供高速率傳輸、高效率頻譜使用率的多媒體服務及對抗頻率選擇的通道衰減。 對於正交分頻多工的通訊系統而言，同步化是非常重要的，影響傳輸效能甚大。本篇論文提出了一個數位電視廣播內部接收機（DVB-T inner receiver）的基頻架構。我們將會討論基頻訊號處理單元演算法，其中包括符元偵測、時間與頻率同步以及通道估測與等化。首先，我們透過電腦模擬建立整體系統流程並針對演算法做出分析與效能評估。最後利用即時軟體的概念以及Scale-Down的設計流程，使用德州儀器之數位訊號處理器(TMS320C5510,DSP)配合C++及Assembly語言實現OFDM調變/解調器及同步接收端演算法，達到能夠實際(Real time)發射DVB-T規格之訊號並驗證接收機演算法之正確性。 To offer high-bit-rate high performance, bandwidth-efficient multimedia services and combat the inevitable frequency-selective fading, the European standard for terrestrial digital video broadcasting (DVB-T) has adopted the orthogonal frequency-division multiplexing (OFDM) technique for broadcasting over wideband wireless channels. The synchronization of symbol timing and sampling clock is very important for the OFDM communication system. This thesis presents a baseband architecture for various corresponding signal processing unit for DVB-T inner receiver. These algorithms serve the functionalities of symbol detection, timing and frequency synchronization and channel estimation/equalization. First, the flow path of overall system is built in computer simulation. Finally, we design the real-time software defined radio implementation of OFDM system and inner receiver, by use of TI C5510 DSP with C++ and assembly language. It could be reaches to transmit DVB-T signal in real time and prove the accuracy of algorithm in receiver.
