利用光传输实验的大气湍流模拟装置测量了光传输特性。采用到达角起伏和光强 闪烁两种方法来测试光传输特性。测试结果表明,温差1200℃时, Fried相干长度为0.740 cm;温差200℃时, 到达角起伏谱频率能达到100 Hz;光强闪烁强度频率可达100 Hz,湍流特征速度约0.1 m/s,外尺度约20 cm。湍 流模拟装置所测的性能指标和实际大气湍流性能较为接近,并且湍流强度具有较好的稳定性和可控性,能满足光传输实验要求。

Using the atmospheric turbulence simulator used in optical transmission experiments, characteristics of optical transmission are measured. Two methods such as the fluctuation of beam’s arrival angle and the intensity of beam’s scintillation are used to measure the characteristics. Results show that, the range of Fried coherence length is 0.740 cm when the difference in temperature is 1200℃, and the frequency of arrival angle fluctuation spectrum ranges can be up to 100 Hz when the difference in temperature is 200℃. The scintillation intensity frequency is up to 100 Hz, feature speed of turbulence is about 0.1 m/s, and the outer scale is about 20 cm. All the tested performances of turbulence simulator are relatively close to the actual atmospheric turbulence’s performance, and the turbulence intensity also has good stability and controllability. So both of them can satisfy the needs of optical transmission experiments.