基于级联交织码的水下LED光通信误码性能分析

为了提升系统误比特率，减小基线漂移以及海水信道的吸收散射等特性对光信号产生的影响，采用了基于水下发光二极管(LED)光通信系统的低密度奇偶校验码(LDPC)-里所(RS)级联交织码方案，在模拟水下LED光通信实验系统的情况下，分析码字方案中RS码、LDPC码以及交织参量对系统误比特率性能的影响，得到了级联交织码方案的优化参量，并进行了实验模拟验证。结果表明，优化后的级联交织码系统与未编码系统、RS码系统、LDPC码系统相比分别可获得3.8dB，2dB，1.2dB的增益，可有效提高系统的误比特率性能。该研究为提高水下无线光通信系统的可靠性提供了参考。

Analysis of error code performance of underwater LED optical communication based on cascaded interleaving code

In order to improve the bit error rate of the system, reduce the baseline drift and the absorption scattering of the seawater channel and other characteristics on the optical signal, a low density parity check (LDPC)-Reed Solomon(RS) cascaded interleaving code scheme based on the underwater light-emitting diode(LED) optical communication system was adopted. Under the simulated underwater LED optical communication experimental system, the effects of RS code, LDPC code, and interleaved parameters on the bit-error rate performance of the system were analyzed in the code scheme, and the optimized parameters of the cascaded interleaving code scheme were obtained and verified by the experimental simulation. The results show that the gain of 3.8dB, 2dB, and 1.2dB can be obtained with the optimized cascaded interleaving code system, compared with the uncoded system, RS code system, and LDPC code system, respectively, which can effectively improve the bit error rate performance of the system. This study provides a reference for improving the reliability of the underwater wireless optical communication system.