Narrowband characterisation of the land mobile satellite channel: A comparison of empirical models

Land Mobile Satellite Systems (LMSS) are subject to severe signal degradation due to. blockage of the line‐of‐sight (LOS) path as well as multipath propagation phenomena. A thorough understanding of the fading effects is of great importance to the design of such a system. This paper reviews and compares ‐ where appropriate ‐ the empirical narrowband models reported in literature. The observation and comparison of these models leads us to the conclusion that this type of channel is strongly dependent on the frequency used For the link, the elevation angle, and the characteristics of the environment in the vicinity of the mobile. The values included clearly indicate the behaviour of the original models and their modifications under different conditions. A table including expected values for the required link margin is presented for the system engineers.