STUDY OF IONOSPHERIC SCATTERING EFFECTS AT 50 MEGACYCLES
Abstract
The forward scattering of 50-mc radio waves from the lower ionosphere was investigated. The observations relate to an approximately 1000-mile circuit from Havana, Illinois to Scituate, Massachusetts. Three separate subjects were investigated: (1) height-gain effects, (2) splitbeam effects, and (3) multipath phase distortion. Three receiving antennas were assembled at elevations designed to align the vertical lobes with the direction of downward scattering at heights of 75, 85 and 100 kms above the path midpoint. An analysis of the output of these antennas showed less variation in received power with elevation than predicted on the basis of simple lobe-alignment theory. There was a qualitative correspondence between diurnal output variations and known variations in the height of the scattering region. Bi-seasonal peak amplitudes were observed during May and June and again in December. Horizontal angle-of-arrival measurements were made by using the split-beam properties of 2 phased Yagi antennas. The properties of the scatter medium downgraded most of the plane-wave advantage of the rhombic over the Yagi. CW amplitude measurements were interrupted to permit single sideband transmissions. Relatively little phase changes were observed during occurrences of high signal levels associated with discrete echoes from over-dense meteor trails. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Dec 30, 1960
- Accession Number
- AD0256868
Entities
People
- Harry Hoogasian
Organizations
- RTX