中性大气折射指数理论研究

THEORETICAL RESEARCH ON NEUTRAL ATMOSPHERIC REFRACTION INDEX

给出大气折射指数与气象参数间的理论关系式,考虑压力温度比的二次项对折射指数的影响,指出在目前的精度测定范围内应该考虑这一效应。同时,基于电磁介质的色散理论,给出了位相与群折射指数随波长变化的理论模型,指出对于同一波段或是不同波段,群折射指数与位相折射指数是可以相互转化的,即从理论上证明可以利用光学天文观测的蒙气差来研究射电波段的大气折射延迟。

Atmospheric refraction index is one of the primary problems in theoretical atmospheric refraction research. A theoretical formula of the relationship between atmospheric refraction index and meteorological parameters was presented,based on the consideration for the influence of quadratic term in the ratio of the pressure and temperature on refractive index. The result indicates that it has to consider present precision measurement range. Moreover,according to electromagnetic medium dispersion theory,a theoretical model of group and phase refraction index with wavelength change,which could be transformed reciprocally for the same or different band was proposed. That means that it is feasibe to study atmospheric refraction delay in radio waveban using boptical astronomical observation.