主权项 |
1. An array of antenna feed elements comprising a plurality of horns, each horn including an aperture at a distal end of the horn, and configured for transmission of electromagnetic energy therethrough, the energy being within a radio frequency (RF) band, at least a first horn being configured with an electrically conductive external surface proximate to the aperture, the external surface being contoured so as to reduce mutual coupling between the first horn and an adjacent horn, wherein:
the external surface is contoured so as to include at least a first portion and a second portion; the first portion has a length l that extends from a longitudinal position proximate to the aperture toward a proximal end of the horn, the first portion being contoured so as to provide, proximate to each adjacent horn, a first lateral gap between the first portion and an external surface of the adjacent horn; the second portion of the external surface extends from the first portion toward an axial position proximate to the proximal end, and provides, proximate to the adjacent horn, a second lateral gap significantly larger than the first lateral gap; the first horn has an aperture external diameter da, and is separated from the adjacent horn by a center to center distance dc-c; and the first lateral gap is approximately constant, throughout length l, length l being approximately n×λ/2, where λ is a characteristic wavelength of the RF band and n is a positive integer. |