Simulation And Implementation Of DVB-T Scrambler/Descrambler And Outer Coder/Decoder

As a result of the digitization of broadcasting technique, areas of broadcasting television, telecommunication and computer technique are constantly infiltrating and merging. These changes drive the basic reform of original broadcasting television system and technique. Currently, because television is moving towards the digitization and high definition, analog television is retiring around the world. Compared with traditional analog television, digital television has fundamental changes in program production, program storage as well as the processing, transmission and broadcasting of signals. Digital television stores and realtime transmits the digitally processed, compressed and encoded video and audio signals which can be received by subscribers. Compared with analog television, digital television has advantages such as high definition, satisfactory audio effect, high spectral efficiency, good anti-interference performance and the facility of storage.The three prevailing terrestrial digital television transmission standards involve DVB-T standard in Europe, ATSC standard in USA, and ISDB-T standard in Japan. This thesis aims at the investigation of DVB-T standard. Basic principles of modules in DVB-T system including transport multiplex adaptation & scrambling, outer coding, outer interleaving, inner coding, inner interleaving, constellation mapping and OFDM modulation are introduced in this thesis, along with the derivation of the RS coding & decoding algorithms.The work of this thesis includes three sections. Firstly, on the basis of the Microsoft Visual Studio 2005 platform, software simulation system of DVB-T baseband signal generation and reception is implemented. The influence exerted on the system performance by DVB-T outer coder & decoder in the context of different channels is simulated and analyzed. Moreover, with hierarchical and non-hierarchical transmission schemes, the influence exerted on the system performance by different modulation modes and modulation parameters is investigated, based on which, the performances of hierarchical system and non-hierarchical system are compared. Finally, the thesis designs outer coder of DVB-T system on the basis of FPGA implementation. Meanwhile, the simulation results of modules of DVB-T system including code stream processing, data scrambling, FIFO, RS coding and convolutional interleaving are obtained on the Quartus II 5.0 platform.