Height variation of drift and anisotropy of the ionospheric irregularities

Abstract

The variation of drift and anisotropy characteristics of the ionospheric irregularities with true height has been studied following the "correlation function method" of Briggs et al. and Phillips and Spencer. Three station fading records on various frequencies adopting Mitra's technique, as modified by Rao, Rao and Murthy, are obtained on nine different occasions and these are utilised in the present investigation. Various parameters describing the drift and anisotropy of the irregularities are averaged from total data for different height levels and are presented along with the results of their gradient in the form of tables. The results which revealed a distinct maximum in the random changes as well as in the elongation of the irregularities in the height range of 200-300 km, suggest that this height range may be the possible location of the irregularities causing spread-F and radio star scintillation.