Turbulence in the lower ionosphere as deduced from increments in absorption and phase path at 150 KC

It is important in the study of ionospheric winds to determine the height of the "diffraction screen" which produces the variations in radio wave field strength, or other characteristics, measured at ground level. A method which may be used to determine this height is developed. It is shown that, under proper conditions, the mean electronic collisional frequency associated with the electron clouds which are presumed to form the "diffraction screen" may be determined by studying change in phase path records obtained simultaneously with absorption records. This value of collisional frequency may then be related to height through an ionospheric model. Single recording stations are used in this comparison of the phase pattern and the amplitude pattern at ground level. The statistical information necessary to the theoretical development is obtained, in the usual way, from a triangular arrangement of receiving stations which record the amplitude of the signal. Preliminary calculations show that the screen which produces the daytime ionospheric winds measured at 150 kc lies in a collisional frequency range from to sec^-1. This would correspond to a height range from 70 to 80 km for our ionospheric model. These results appear to be in good agreement with recent work by Kellogg (1951) from the meteorological viewpoint.