Preliminary results of PROSAT maritime-mobile propagation measurements

A program of measurements has been carried out to characterize the satellite-mobile link at L-band as part of PROSAT, a program conducted by ESA to define future satellite-mobile communication systems. Here, some early results of an analysis of these measurements are reviewed with particular reference to the maritime-mobile channel. It is found that in most cases the propagation channel can be modeled by Rician statistics resulting from a direct signal and a sea-reflected diffuse multipath signal. The Rician model can be characterized by the carrier to multipath ratio and the 1/e fading bandwidth, both of these parameters being dependent on the elevation and the sea. It is also found that at low elevation angles, the estimated carrier to multipath ratio is largely independent of the antenna gains for the types of antenna used.