THE RELATIVE MOTIONS OF TWO INDEPENDENT COMMUNICATION SATELLITES.

This report presents a method of determining the relative positions of two independent communication satellites and the times during which these two satellites are in the proper positions for two specified modes of communication. The method developed is to be used in support of two separate satellite experiments to determine if communication is possible between two satellites, which are physically out-of-line-of-sight of each other, via bending and reflecting radio waves in and through the ionosphere. Presented is a mathematical model that determines the positions of two independent satellites as a function of time in the earth coordinate system in terms of co-latitude, longitude, and altitude. Both satellites are tracked from their injection points throughout their orbits in finite-time increments for a preselected time. In conjunction with determining the positions of the satellites, the model also determines the time, with respect to some given time reference, when the satellites enter and leave the line-of-sight of any set of designated geographical positions as well as when the satellites enter and leave the line-of-sight of each other. The recorded times are summed, and the percentages of the recorded times, based on the total time considered, are determined. Author