塔康试飞大气折射效应修正

塔康飞行试验中，由于对流层大气的折射效应，塔康测距输出并不直接对应于作为基准的 GPS 测距值，应该对 GPS 测距值进行修正。本文采用射线跟踪法对此问题进行了分析研究，得出了修正计算公式，并进一步探讨了实际应用的工程数值算法，最后给出了计算实例。

Correction for Atmospheric Refraction in Flight Test of TACAN

GPS technique has been widely applied in use for testing airborne radio navigation system as location and velocity references. In case of testing TACAN, the range information from TACAN is not equal to the reference range result from GPS position location due to tropospheric refraction. A scheme for correcting for the effect of atmospheric refraction is required. In this paper, a formula which can be used to compute the refraction error is derived on the basis of ray-tracing. In addition, an algorithm which obtains an approximate solution of the formula is presented. The performance of the method is illustrated with numerical examples.