Gain of Electromagnetic Horns

An experimental investigation of the gain of pyramidal electromagnetic horns is described. For the horns tested it was found that (1) the "edge effects" are less than 0.2 db so that the gain of the horns may be computed to that accuracy from their physical dimensions and Schelkunoff's curves; and (2) for the transmission of power between two horns the ordinary transmission formula is valid, provided that the separation distance between the horns is measured between the proper reference points on the horns, rather than between their apertures.