The effects of ground-reflected rays and atmospheric inhomogeneities on multipath fading

Ray tracing through a single horizontally stratified atmospheric layer has been used to support evidence that defocusing of the direct ray, combined with surface multipath, can have an important effect on the performance of overland microwave line-of-sight (LOS) links. The same link and horizontally stratified layer proposed by A.R. Webster (1983) are used to exhibit the agreement between previous results and the present ones, to display a numerical example of multipath effects on terrestrial microwave LOS, and as a reference for detailed discussions. The effects of the combination of the horizontal stratification with a wave-like structure are analyzed. it is seen that the vertical displacement of the structure across the radio link has a strong impact on the parameters of the direct ray, which is translated into fast variations of the received signal around its average value. >