Research On LDPC Codes Technology Applied To Broadband Power Line Communication

Based on the investigation into the principle of channel coding technology and the characteristics of power line communication, we apply LDPC (Low Density Parity Check) codes to AWAN (Additive White Class A Noise) channels which is usually used as the model of impulsive noise environment of power line channels. We propose a modification for the LLR (Likelihood Ratio) of the initial information to Log-BP (Log domain Belief Propagation) decoding which is suitable for AWAN channels. At last, compared with the original Log-BP decoding, we show the BER (Bit Error Rate) performance of the modified Log-BP decoding over AWAN channels by Monte-Carlo simulation, the result shows that the modified Log-BP decoding has about 11dB gain with the reasonable values A andΓ. Used programmable logic device for the design, based on LDPC algorithm theory analysis and the top-down design method, we complete the functions of the LDPC encoder and decoder. In QuartusII, we make timing simulation to the LDPC decoder and encoder, which verify the correctness of the theory.