A model to describe the distribution of transmission path elevation angles to the Iridium and Globalstar satellite systems

The quality of a satellite-based personal communications system (S-PCS) transmission path is heavily influenced by its elevation angle. The distribution of path elevation angles varies with a user's latitude but can be characterized by a single distribution with changing parameters. Through simulation, model fitting and regression analysis, a set of equations is presented which allows the distribution of elevation angles to both Globalstar and Iridium systems to be determined for any point on the Earth between /spl plusmn/60/spl deg/ latitude.