Auroral radar backscatter at off-perpendicular aspect angles due to enhanced ionospheric refraction

Journal Article · Thu Sep 01 00:00:00 EDT 1994 · Journal of Geophysical Research

DOI:https://doi.org/10.1029/94JA00925· OSTI ID:166274

Uspensky, M V; Pivovarov, V G ^[1]; Romanov, V I ^[2]

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1. Polar Geophysical Institute, Murmansk (Russian Federation)
2. Radiotechnical Institute, Moscow (Russian Federation)

This paper studies the effect of ionospheric refraction upon auroral radar backscatter under conditions where the aspect angle appears far from ideal, i.e., when the unrefracted ray path trajectory is at least a few degrees from the perpendicular to the Earth`s magnetic field. It is found that wave trapping by curved electron density layers can cause ionospheric refraction as large as 20{degrees}, even at 150 MHz. This suggests that many so-called off-orthogonal VHF echoes are in reality due to backscattering at near-orthogonal aspect angles, the discrepancy arising from increased ionospheric refraction by curved or tilted layers. 28 refs., 3 figs.

• OSTI ID: 166274
• Journal Information: Journal of Geophysical Research, Vol. 99, Issue A9; Other Information: PBD: 1 Sep 1994
• Country of Publication: United States
• Language: English

Related Subjects

66 PHYSICS
IONOSPHERE
REMOTE SENSING
REFRACTION
RADAR
BACKSCATTERING
MHZ RANGE
RADIOWAVE RADIATION