In this paper, a wide-spectrum orbital angular momentum (OAM) based free space communication system is experimentally demonstrated. The wide-spectrum laser can be generated using narrow-linewidth pulses to pump nonlinear fiber and the OAM beam can be generated with spatial light modulator (SLM). In the experiment, a controllable atmospheric turbulence simulation device was used to ensure a unified test environment. The results show that with the combination of wide-spectrum laser and OAM beam, the received sensitivity can achieve a 4.23 dB gain compared with narrow-linewidth Gaussian beam-based communication system in weak atmospheric turbulence environment.

中文翻译：

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可调谐大气湍流中宽谱OAM波束的传输特性

在本文中，实验证明了基于宽谱轨道角动量（OAM）的自由空间通信系统。可以使用窄线宽脉冲泵浦非线性光纤来产生宽光谱激光，并且可以使用空间光调制器 (SLM) 来产生 OAM 光束。实验中采用可控大气湍流模拟装置，保证统一的试验环境。结果表明，在弱大气湍流环境下，采用宽谱激光与OAM光束相结合，接收灵敏度较窄线宽高斯光束通信系统提高4.23 dB。