Some aspects of ionospheric drifts using partial and total reflections from the lower ionosphere

Abstract

Two different aspects of ionospheric drifts are discussed in this paper. The effect of the receiver triangle size on the drift parameters derived from full correlation analysis is investigated, when partial reflections from altitudes near 90km are used. It is found that, for frequencies near 2 MHz, the scale of the diffraction pattern on the ground is of the order of 100 m, and that the drift parameters show little dependence on triangle size for aerial separations greater than 100 m. In addition, a number of drift records obtained using both partial and total reflections have been analysed by a dispersion method in order to look for any systematic variation of the drift velocity with fading frequency. It is shown that dispersion is present in only a minority of records, but that it occurs more frequently for the partial reflection examples than for records of totally reflected waves from the E-region. Some possible interpretations of this result are discussed.