Modelling fading properties for mobile satellite link channels using non-stationary hidden Markov model

Hidden Markov models (HMMs) of propagation fading channels are widely used. However, the standard HMM cannot effectively predict the state duration of a propagation channel. This investigation study develops a propagation channel model using a non-stationary hidden Markov approach to accurately predict the characteristics of the satellite-to-earth propagation channel. The proposed model can not only describe the propagation state characteristics but also capture the relationship between the times associated with the states. Typical measured data are used to derive optimal model parameters and generate a fading signal simulator. A close match between the simulated and measured data shows that the proposed model satisfactorily predicts the first- and second-order statistics of the propagation characteristics in several user environments. This new method produces more accurate simulation results than the standard HMM, in predicting the fading properties of the state duration statistics.