Directional array for near vertical incidence skywave antenna

摘要

An antenna array comprising: four dipole antennas configured to function together as a directional, near vertical incidence skywave (NVIS) antenna with reduced side lobes, wherein each dipole antenna comprises two conductive elements and a feed point disposed between the two conductive elements, wherein the conductive elements of each of the four dipole antennas are disposed in an x-y plane of an x-y-z mutually orthogonal axes coordinate system, and wherein the conductive elements are substantially parallel with the x-axis and the x-y plane is substantially parallel with a ground plane; and wherein the feed points of the four dipole antennas are positioned on the x-y plane at approximately (x, 0), (−x, 0), (0, y), and (0, −y), and wherein the x-y plane is separated from the ground plane by a distance h that is less than or equal to 1/10 the wavelength (λ) of an operating frequency.