On the use of QC-LDPC code for data transfer using short and medium block length

Quasi Cyclic Low Density Parity Check codes (QC-LDPC) is proposed to reduce the complexity of the Low Density Parity Check codes (LDPC) further while obtaining the similar performance. Our proposed QC-LDPC presents an improved construction of circulant sub-matrices based QC-LDPC at high SNR. The proposed construction yields a performance gain of about 1 dB at a 0.0003 bit error rate (BER). Proposed code is tested on 4 types of decoding algorithm and compared. Proposed algorithm is also compared with the existing QC-LDPC and the proposed approach outperforms the existing one at high SNR. Simulation is also performed varying the number of horizontal submatrix and the result shows that the parity check matrix with smaller horizontal concatenation shows better performance.