Ionospheric Scintillation,
Abstract
A renormalization technique, employed in the spirit of the formal theory of scattering, is applied to the problem of ionospheric scintillation. Using the forward scattering approximation for wave propagation and a Markov approximation for ionospheric fluctuations, one derives renormalized moment equations descriptive of the wave statistics. The propagation of the two and four point wave statistics through the ionosphere are obtained using a slow quasiparticle distribution function S. For the case of an ionospheric structure function H(xi) = a xi(squared) where xi is a transverse distance, one can obtain exact analytical solutions for the wave statistics. For an arbitrary fluctuation spectrum. one can evaluate the S function along a quasiparticle trajectory and thereby infer second moments exactly and fourth moments approximately. Knowledge of the S function enables one to ascertain statistical properties, such as average intensity, two point intensity correlation and the scintillation index S(4). The Scintillation index for the case of a plane wave propagating through the ionosphere is studied for the case of an arbitrary power spectrum of ionospheric fluctuations. Peaks superposed on a power law spectrum are found to increase the value of S(4). A focusing effect on the S(4) vs. z variation is observed in the strong scintillation limit. An experimental power spectrum, corresponding to relative density fluctuations of about 20% as obtained from situ measurements by the Atmospheric Explorer-E satellite, is used to calculate the corresponding S(4) for night time equatorial scintillations. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Sep 01, 1980
- Accession Number
- ADA092720
Entities
People
- David M. Wu