A THEORY OF THE CURVATURE CORRECTION IN ELECTROMAGNETIC DISTANCE MEASUREMENT
D.C. Williams · Survey Review · 1975
The effect of beam bending on an optical path length through the atmosphere is evaluated by a simple method which confirms previous theory. The analysis is generalized to the case where the beam path and the path to be measured are both slightly curved, for example when the required path follows the geoid. The known result for uniform bending is confirmed, and the formulae are readily applicable to non-uniform cases.