Research On LDPC-DFH Code Modulation And Demodulation System Based On Hard Decision Decoding

Abstract

In order to reduce the bit error rate of differential hopping transmission, differential frequency hopping (DFH) is combined with low density parity check code (LDPC). On the basis of not adding more system complexity, the hard decision bit inversion algorithm (BF) and weighted error check based bit inversion algorithm (WVBF) are proposed to decode LDPC-DFH system. The check matrixes of different generation methods are used respectively. The BF decoding method and WVBF decoding method are used to simulate the Gaussian channel and Rician channel. The influence of different decoding methods on the bit error rate is discussed. The simulation results show that the BER of the DFH system with LDPC code is lower than that of DFH without LDPC, and the WVBF algorithm is better than the BF algorithm.