Analysis And Simulation Of Encode And Decode Of LDPC Code In DVB-S2 Standard

LDPC code is a type of error correcting block code with very sparse check matrix which was first proposed by Gallager in the early 1962. But because of the technology, it was scarcely considered in the 35 years that followed. The study of LDPC code was resurrected with the work of Mackay and others. They found that it possessed sparse (low-density) parity-check matrices. It also provided near-shannon limit performance and it has highly parallelizable decoder architecture.DVB-S2 is the next generation standard of the digital satellite broadcasting.It adopted the concatenation of BCH outer code and LDPC inner code as the Forward Error Correction (FEC). Therefore, the FEC subsystem of DVB-S2 has powerful correcting ability.In this paper, we have made some research on the LDPC code of DVB-S2. Firstly, we proposed the basic principle of the LDPC code. We introduced the definition, the expression method and construction method of the LDPC code. Then we explain the LDPC encoding method. Next we study the encoding algorithm proposed in DVB-S2 standard. We also analyzed the periodic structure of the LDPC parity-check matrix. Then we analyzed the decoding algorithm based on the message passing. We also gave the simulation results of the performance of the LDPC code. It is found that the min-sum algorithm can be used in DVB-S2 standard. Finally, we studied and analyzed the decoder of the LDPC code.