一种基于超短基线干涉仪的大气湍流参数测量算法

目前,对流层大气湍流造成的随机变化的相位误差已严重影响了高频段深空测控通信系统的工作性能.为了量化湍流强度,基于超短基线干涉仪系统接收的地球同步卫星信号,统计信号干涉相位的标准偏差,结合经典的Kolmogorov-Obukhov"2/3"扰动理论和随机场理论建立了大气湍流参数计算模型,实时获取表征湍流强度的物理量:大气折射率结构常数Cn^2.分别在郑州、杭州进行了连续多天的晴天、雨天相位观测试验,利用试验数据计算Cn^2,并利用气象探空数据经验模型进行了验证.试验数据计算结果显示:Cn^2在郑州晴天的正午前后要明显高于早晨和傍晚,而在杭州雨天则没有明显的规律性.Cn^2在10^-15~10^-13的数量级范围变化,与经验模型计算的结果相吻合,验证了算法的合理性和准确性.

A method of measuring atmospheric turbulence parameter based on very short baseline CEI

At present, work performance of the high frequency deep space TT&C system is badly affected by the random change of phase error arose by troposphere atmospheric turbulence. For the purpose of quantifying turbulence intensity, based on the very short baseline CEI receiving GEO satellite signal, the standard deviation of interferometer phase are statisticed, using classical Kolmogorov-Obukhov "2/3" turbulence theory and random field theory, and a method of atmospheric turbulence parameter is proposed to obtain atmospheric refractive index structure constant which can symbolize turbulence intensity. The phase observation experimentations were carried through in Zhengzhou and Hangzhou for a few sunshine days and rainy days, and the atmospheric refractive index structure constants were computed by experimentation data, and compared with the results of experience model using radiosonde data. The results show that C_n2 are much larger at noon than in morning and evening on sunshine days, and have no distinct law on rainy days, and are changed between 10-15 and 10-13, which is consistent with the results calculated by experience model to validate the rationality and accuracy of this method.