Based On The Dtmb Originated The Fpga Implementation Of The System

Digital Television Terrestrial Multimedia Broadcast (DTMB) standard adopts theframe structure which is synchronized with the absolute time, time-domain synchronousorthogonal frequency division multiplexing (TDS-OFDM) modulation and errorcorrection technology. The error correction technology is based on the concatenation ofBCH outer code, LDPC inner code and interleaving. DTMB can support high-definitionTV, standard definition TV and multimedia data broadcasting business simultaneously.Compared with the other three terrestrial broadcasting international standard,DTMB has a fast code capture, a robust synchronization tracking, an efficient spectrumutilization ratio, a strong anti-interference and a better mobile reception.Focusing on the coding, modulation and frame strcture engineering realization ofDTMB launching system, the dissertation has done main works as follows:1. We study DTMB launching system including the channel coding, the channelmodulation and the frame structure. According to the procedure of data processing, weoptimize the system structure and propose the implementation scheme.2. According to the system structure,we design and implement the functionmodules of the channel coding, modulation and the frame structure based onFPGA.Furmore we simulate and test these modules.The channel coding includes thescrambling code, BCH coding,LDPC coding,bit symbol interleaving andfrequency-domain-interleaving.The channel modulation and the frame structure includethe generation of the frame body, the processing of frame body (FFT and IFFT of3780points), the generation of the signal frame and post-processing of baseband singnal.According to the quasi-cyclic feature of block matrix of LDPC generator matrix, westudy an encoding scheme which decomposes it by column within the matrix, andcompute it by row between the matrix. This LDPC encoder decreases the designingcomplexity and memory space.3. Set up a FPGA testing platform for DTMB encoding and modulation system.Debug and verify the platform after each module is cascaded.