LDPC码在水下激光通信中的研究  

Study about LDPC codes applied in underwater laser communication

作　　者：孙丽华[1] 陈名松[1] 李天松[1] 易淼[1] 

机构地区：[1]桂林电子科技大学信息与通信学院,桂林541004

出　　处：《激光技术》2009年第6期604-606,共3页Laser Technology

基　　金：广西省科学基金资助项目(0832012);广西省研究生创新基金资助项目(2008105950810M414)

摘　　要：为了研究低密度奇偶校验码在水下激光通信系统中的性能,采用软判决迭代译码算法对系统误比特率进行了仿真,并对水下激光通信的信道模型和低密度奇偶校验码的编译码方式进行了探讨。在一定码长和调制阶数条件下,当信号光子数 n_s 增大时,可以使误比特率降到10^(-5)以下。结果表明,通过利用光电检测输出的软信息进行低密度奇偶校验软判决译码可以明显地降低系统误比特率。In order to study the performance of low density parity check （LDPC） codes applied in an underwater laser communication system, its bit error rate was simulated by means of soft-decision decoding algorithm. A model of underwater laser communication channel was introduced, and then the encoding and decoding algorithm of LDPC codes was studied. For a certain code length and modulation order, the bit error rate can be reduced to 10^-5 with the signal photon number ns increase. The simulation results show that the bit error rate of the system can he improved obviously by means of LDPC soft-decision decoding based on the output soft information of the photo detector.

关 键 词：光通信 水下激光通信 低密度奇偶校验码 脉冲编码调制 软判决译码 

分 类 号：TN929.3[电子电信—通信与信息系统]