可见光通信中一种围长为8的QC-LDPC码构造方法

A Construction Method of QC-LDPC Code with Girth-8 in Visible Light Communication

摘要:

为了提高可见光通信(Visible Light Communication,VLC)系统的性能,基于Hoey序列提出了一种围长为8的准循环低密度奇偶校验(Quasi-Cyclic Low-Density Parity-Check,QC-LDPC)码的新颖构造方法。用该方法构造的QC-LDPC码不含4、6环,且可灵活选择不同码率。然后用所提出的构造方法构造了码率为0.5的Hoey-QC-LDPC(1536,8)码,并运用所搭建的VLC系统仿真模型对其进行了仿真性能分析。仿真结果表明,在误码率(Bit Error Rate,BER)为10-6时,该Hoey-QC-LDPC(1536,8)码与同码率的基于最大公约数(Greatest Common Divisor,GCD)算法构造的GCD-QC-LDPC(1540,0)码、采用滑动矩形窗口(Slide Rectangular Window,SRW)构造的SRW-QC-LDPC(1540,0)码以及基于卢卡斯数列(Lucas Sequences,LS)构造的LS-QC-LDPC(1536,8)码相比,其净编码增益(Net Coding Gain,NCG)分别提高了0.50、0.56与1.09dB。

Abstract:

In order to improve the performance of visible light communication(VLC) system, a novel quasi-cyclic low-density parity-check(QC-LDPC) code with girth-8 construction method was proposed based on Hoey sequence. The QC-LDPC codes constructed by this method do not contain 4 or 6 circles, and can be flexibly constructed with different bit rates. Then the H-QC-LDPC(1536,8) code with a code rate of 0.5 was constructed with the proposed construction method, and the performance was analyzed in the established VLC system simulation model. Simulation results show that when the bit error rate(BER) is 10-6 and the code rate is 0.5, the net coding gain(NCG) of the Hoey-QC-LDPC(1536,8) code constructed by this method is respectively 0.50,0.56 and 1.09dB higher than those of GCD-QC-LDPC(1540,0) code based on the greatest common divisor(GCD), SRW-QC-LDPC(1540,0) code based on the sliding rectangular window(SRW) and LS-QC-LDPC(1540,0) code based on the lucas sequence(LS).