Results of Studying the Daytime Polar Ionosphere by the Radio Occultation Method on Satellite-To-Satellite Paths

We analyze specific features of the radio occultation method and the possibility of using it to study the altitude profiles of electron density and the characteristics of sporadic formations in the daytime polar ionosphere of the Arctic at latitudes above 67° in the period from June 19 to July 1, 2015. Electron density at altitudes of 90 to 650 km is determined by ionospheric occultation sounding on GPS–FormoSat satellite-to-satellite paths, and its dependence on solar illumination at an altitude of 100 km is demonstrated. Data on sporadic Es formations at altitudes of 80 to 120 km are presented. Two types of Es structures attributed to the wind shear and precipitation of energetic particles from the magnetosphere are discussed.