On the Radio Wave Propagation in a Stratified Atmosphere II

Abstract

In this paper a method is developed for determining the electromagnetic field produced by a microwave antenna. The theory is developed for the condition that the index of refraction of the atmosphere varies with height as A + B h + C h 2 , for the flattened earth. From the rigorous solution the geometrical-optical description is derived. The Hertzian vector is split into the geometrical series, each term of which corresponds to the rays reflected 1, 2, 3, … times by the earth, when the “duct” is formed. Among these rays there are the rays whose propagation constants are complex number. The existence of these rays explains the “radio duct phenomena” in the cases when the transmitter and the receiver are located both out of the “duct”, and when they are in and out of the “duct”, respectively. For the field strength in the vicinity of the cusp of caustic, we use the original integral and calculate by numerical integration. The field strength of the reflected rays at the cusp of caustic is 3.2 times that of f...