Radar-lunar measurements of the electron content of the ionosphere

The Faraday rotation of 425-Mc/s radar signals reflected from the moon's surface has been analyzed to yield data on the ionization in the ionosphere. The experimental measurements were taken at Trinidad, West Indies, between January and July 1960. A method is presented which permits resolving the ambiguity of the number of rotations of the plane of polarization when one frequency is employed in radar-lunar studies. The total integrated electron density in a vertical column through the ionosphere inferred from the radar Faraday data is found to undergo a diurnal variation, having a maximum value during the late afternoon. An analysis of other ionospheric parameters, such as the equivalent slab thickness, the scale height, and the ratio of the electron content above the peak of the F layer to that below, is also presented.