Performance of differential phase shift keying maritime laser communication over log-normal distribution turbulence channel

Laser communication is essential part of maritime-terrestrial-air intelligent communication/sensor network. Among them, different modulation formats would play a unique role in specific applications. Based on Rytov theory, we discussed system performance of the maritime laser communication with repeated coding technology in several modulation schemes. The closed-form expression of average bit error rate(BER) from weak to moderate atmospheric turbulence described by log-normal distribution is given. Differential phase shift keying(DPSK) modulation, as a potential solution for future maritime laser communication, has attracted a lot of attention. We analyzed the effects of atmospheric turbulence parameters(visibility, refractive index structure coefficient, non-Kolmogorov spectral power-law exponent, turbulence inner scale) and DPSK system parameters(receiver aperture diameter, repeat time) on average BER in detail. Compared with the aperture-averaging effects, the system BER can be well suppressed through increasing repeat time. This work is anticipated to provide a theoretical reference for maritime laser communication systems.     

光纤放大器辐照损伤光致退火实验研究

针对辐照环境下光纤放大器输出性能的退化问题,对光纤放大器进行了辐照损伤后的光致退火实验研究.首先,介绍了辐射对光纤放大器的影响,在总辐照剂量约为280 krad时进行了辐照实验,获知辐射会引起输出功率、光信噪比分别下降7 dB、18 dB;然后,根据光致退火机理,进行了光纤放大器光致退火实验.实验结果表明:光致退火降低...