Physical statistical modelling of the land mobile satellite channel based on ray tracing

The paper presents a model of the land mobile satellite channel, predicting the statistical fade distribution in a given urban or suburban area descri bed by objective data. The channel modelling is based on a conditional Rici an distribution, whose parameters are related to physical parameters such a s building height, street width, azimuth and elevation angles of the satell ite link. Relationships between Rician and physical parameters are estimate d by means of a ray-tracing method based on the uniform theory of diffracti on, and statistically varying physical parameters are described by analytic al distributions. The model is applied to a typical suburban area, and very good agreement is found between simulations of the fade distribution and r adio measurements at L, S and X bands for two elevation angles.