Construction of High Performance Block and Convolutional Multi-Edge Type QC-LDPC codes

摘要

We present code sieving method for construction of long-length high performance Block and Convolutional Multi-Edge Type QC-LDPC codes (MET QC-LDPCC) under the fixed point (Quantized) reduced complexity box-plus (QRCBP) decoder. Proposed method use iterative decoding threshold protograph sieving and simulated annealing method for QC lifting with cycles EMD maximization. Using proposed method we construct base matrix of MET-LDPC code with size 92 20, maximal column weight 17, with weight one circulants, code rate 0.8, 2 variable nodes punctured which have iterative decoding threshold Eb/No = 2.333 dB under 200 iterations of QRCBP over an AWGN channel with QPSK modulation on Bit Error Rate below 10^-, 0.289 dB from Shannon limit. Simulation results of Block with code length N = 261924 and MET QC-LDPCC codes, equivalent block length N = 785772 constructed using simulated annealing lifting of base matrix under 32 iterations of QRCBP show Eb/No = 2.56dB, Eb/No = 2.478dB below BER10^-15, respectively. Cole's importance sampling under QRCBP show that proposed codes error-floor BER ≈ 10^-16.