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From: David Jefferies
Date: 25 Nov 2002
Time: 15:14:40
Remote Name: 195.92.168.164
Marc, <><><> You are right about the scattering of em radiation from the ground. There are various ways to view this. One is, as you say quite rightly, that the ground -induced currents contribute to the radiation. Another is that the ground is a kind of lossy mirror, which reflects the em radiation incident upon it and that the induced currents are just a bye-product. The preferred way people have of looking at this is to treat it as a "method of images" problem, in which the ground is removed completely and a fictitious image antenna added to the original source, but located underground. The total radiation field is then formed from the array pattern of the antenna and its virtual image. See http://www.ee.surrey.ac.uk/Personal/D.Jefferies/reflection.html <><><> Regards, <><> David.