几种LDPC码在无线光通信系统中的性能比较

为了提高无线光通信系统的性能，文章研究了几种低密度校验码（LDPC）在无线光通信系统中的运用．MATLAB仿真结果表明，LDPC码能对弱湍流信道起到一定的抑制作用从而提高了通信系统的可靠性．构造这几种码时，在都未对其进行优化的J睛况下，弱湍流信道下的准循环LDPC（QC_LDPC）码的误码性能略差于Mackay随机LDCP码，优于π-旋转LDPC码，但QC_LDPC码和π-旋转LDPC码编码简单易于硬件实现，实用性更强．

Performance comparison for several kinds of LDPC codes in wireless optical communication system

In order to improve the performance of the wireless optical communication system, the application of some kinds of LDPC （low density parity check） codes in the wireless optical communication system is examined. The MATLAB simulation method is used, showing that LDPC codes can restrain the weak turbulence channel to a certain extent, so as to improve reliability of the communication system. When constructing these LDPC codes, under the circumstances of not optimizing them, the BER （bit error rate） performance of the QC （quasi-cyclic）_LDPC code in weak turbulence channel is slightly lower than that of Mackay random LDPC code, and it is superior to π-rotation LDPC code. While the QC_LDPC code and π-rotation LDPC code are simple and easy to be implemented by hardware, therefore, they are more practical.