Spatial Properties of Ionospheric Radio Propagation As Determined with Half-Degree Azimuthal Resolution

摘要

The purpose of the research was to investigate experimentally the properties of oblique ionospheric radio propagation which could degrade or limit the performance realized by a very wide-aperture (2.5 km), high-frequency broadside array. 'High-frequency' (HF) refers to the frequency band from 3 MHz to 30 MHz. A broadside antenna array is one whose main lobe direction is roughly perpendicular to the line of its elements. Since the performance of such an array can most meaningfully be measured in terms of its horizontal pattern (beamwidth and sidelobe levels), the emphasis of this study was upon the apparent azimuthal pattern of an array when receiving ionospherically propagated radio energy emanating from a point source. (Author)