基于平衡不完全区组设计(BIBD),深入分析与研究了准循环低密度奇偶校验(QC-LDPC)码的一种新颖构造方法,并通过该构造方法构造了3种同码率不同码长的QC-LDPC码,通过对这3种QC-LDPC码的仿真分析表明,同码率下,码长越长性能越好。同时在BER=10-6时码率均为93.7%的情况下,所构造的BIBD-QC-LDPC(5392,5056)码的净编码增益(NCG)比已广泛应用于光通信系统中的经典RS(255,239)码和ITU-T G.975.1中的LDPC(32640,30592)码分别提高了约2.13dB和1.41dB。因而其纠错性能更强,更适用于高速长距离光通信系统。该新颖构造方法简单灵活且编译码更容易实现。 Based on BIBD, a novel method of constructing quasi-cyclic low-density parity-check (QC-LDPC) codes is deeply analyzed and constructed. Three different code rates The long QC-LDPC codes, through the simulation analysis of these three kinds of QC-LDPC codes, show that with the same code rate, the longer the code length, the better the performance. Meanwhile, the net coding gain (NCG) ratio of the constructed BIBD-QC-LDPC (5392,5056) codes has been widely used in the classic of optical communication system with the BER of 10-6 being 93.7% The RS (255,239) codes and the LDPC (32640,30592) codes in ITU-T G.975.1 improve by about 2.13dB and 1.41dB, respectively. So its error correction performance is stronger, more suitable for high-speed long-distance optical communication system. The novel construction method is simple and flexible and the codec is easier to implement.