高速码率兼容DVB-S2的LDPC译码器的FPGA实现

A multi-rate LDPC decoder architecture for DVB-S2 codes based on FPGA is proposed. Through elementary transformation on the parity check matrices of DVB-S2 LDPC codes, a new matrix whose left is a QC sub-matrix and right is Transformation of Staircase lower triangular (TST) sub-matrix is obtained. The QC and TST are designed separately, therefore the successful experience of the most popular Quasi-Cyclic (QC) LDPC decoder architecture can be drawn on. While for TST sub-matrix, the variable nodes updating only need to be considered and the check nodes updating is realized compatibility with QC sub-matrix. Based on the proposed architectures, a multi-rate LDPC decoder implemented on Xilinx XC7VX485T FPGA can achieve the maximum decoding throughput of 2.5 Gbit/s at the 20 iterations when the operating frequency is 250 MHz, which demonstrates the highest throughput compared with the state-of-the-art works.