关键词: 低密度奇偶校验（LDPC）码, 中国剩余定理, 分量码, 快速编码

Abstract: For any row weight L, a new family of （3, L）-regular Low-Density Parity-Check（LDPC） codes is proposed explicitly with girth eight as the first component code. Another Low-Density Parity-Check（LDPC） codes with the capacity of fast encoding is proposed as the second component code. Employing these new codes  in the construction method of Chinese Remainder Theorem（CRT）, a novel class of compound QC-LDPC codes is presented with both girth at least eight and very flexible code lengths. The proposed codes have the above two characteristics. Simulation results show that compared with QC-LDPC code constructed by IRCMS algorithm, the proposed codes have comparable or even better performance, while the encoding complexity is lower; moreover, the proposed codes outperform the array code with dual-diagonal parity structure about 0.3 dB gain at BER of 10－4 with the capacity of fast encoding. Compared with PEG-CRT-LDPC codes, the proposed codes have better performance while the encoding complexity is lower.

Key words: Low-Density Parity-Check（LDPC） code, Chinese remainder theorem, component code, fast encoding