We experimentally demonstrate a 2-μm free-space data transmission system in a simulated atmospheric turbulent device with an actively mode-locked holmium-doped fiber laser. The central wavelength can be adjusted from 2035.6 nm to 2050.2 nm with optional repetition rates of 1.01 GHz and 2.02 GHz, respectively, and the pulse is stabilized by adding a fiber Fabry-Perot filter in the laser cavity. The pulse sequence can be modulated by a digital signal and transmitted in a tunable simulated atmospheric turbulent channel. Compared with backto-back (BTB), the optical signal-to-noise ratio (OSNR) of 2-μm laser carrier reduces from 15.04 dB to 6.67 dB under the condition of Cn2 = 5.71 × 10-16m-2/3, and the received power jitter increases from ±0.04 dB to ±0.74 dB. The sensitivity of the 2-μm data transmission system is -19.52 dBm. In addition, we compare the average receiving power standard deviation and power penalty between the 2-μm laser and a 1.55-μm laser under the same propagation conditions. The experimental results demonstrate that the 2-μm laser communication system realizes superior performance in a weak turbulent channel.

中文翻译：

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基于主动锁模钬光纤激光器的 2-$\mu$ m 自由空间数据传输


我们在模拟大气湍流装置中通过主动锁模钬光纤激光器实验演示了 2μm 自由空间数据传输系统。中心波长可在2035.6 nm至2050.2 nm之间调节，可选重复频率分别为1.01 GHz和2.02 GHz，并通过在激光腔中添加光纤法布里-珀罗滤波器来稳定脉冲。脉冲序列可以通过数字信号进行调制，并在可调谐模拟大气湍流通道中传输。与背靠背（BTB）相比，在Cn2=5.71×10-16m-2/3条件下，2μm激光载波的光信噪比（OSNR）从15.04 dB降低到6.67 dB，接收功率抖动从±0.04 dB 增加到±0.74 dB。 2μm数据传输系统的灵敏度为-19.52dBm。此外，我们还比较了相同传播条件下2μm激光器和1.55μm激光器的平均接收功率标准偏差和功率损失。实验结果表明，2μm激光通信系统在弱湍流通道中实现了优越的性能。