NORTHERN LATITUDE PROPAGATION

• Main Author: Liszka, Ludwik
• Other Authors: KIRUNA GEOPHYSICAL OBSERVATORY (SWEDEN)
• Format: Text
• Language: English
• Published: 1963
• Subjects: Atmospheric Physics; Radiofrequency Wave Propagation; Radio Communications; *MAGNETOOPTICS; *SATELLITE COMMUNICATIONS; *RADIO SIGNALS; *DISTORTION; *DIURNAL VARIATIONS; *IONOSPHERIC SCINTILLATION; GEOMAGNETISM; SWEDEN; PERIODIC VARIATIONS; ARTIFICIAL SATELLITES; FOREIGN REPORTS; Kiruna
• Online Access: http://www.dtic.mil/docs/citations/AD0402303; http://oai.dtic.mil/oai/oai?&verb=getRecord&metadataPrefix=html&identifier=AD0402303

Satellite recordings made at Kiruna Geophysical Observatory at frequencies 20 and 54 Mc/s during the last three years are investigated with respect to the occurrence of scintillation with emphasis on the 54 Mc/s results. Studies of diurnal and seasonal variations of scintillation at 54 Mc/s show that the shape of the diurnal curve is dependent on magnetic activity and that seasonal variations are not important. The depth of scintillation at 54 Mc/s is better correlated with magnetic activity than at 20 Mc/s. There exists a difference between daytime and night-time scintillation. A statistical analysis of the diffraction pattern produced by radio waves from Transit IV A at 54 Mc/s is also presented. The most important result is the evidence that auroral zone scintillation may be produced at altitudes below F-maximum. Investigation of the shape of ionospheric Irregularities have shown that if these are assumed to be two-axial ellipsoids orientated along the magnetic field lines, axis ratios of order of magnitude 10 will be obtained.