Time variant models for satellite channel

Different methods used to design mathematical models for a satellite channel are considered. These channel models, based on homogeneous Markov chains, are used as a basis for evaluation of OSI layer two protocols. The parameter design of the models is based on measured block error probabilities, obtained by German PTT on the Olympus 20/30-GHz channel. Since the block error rate is one of the most important issues for a satellite channel, the modeling will be based on block-oriented data transfers. The authors compare block error probabilities of Gilbert´s (1960) and Fritchman´s (1967) models with two generative time variant models. The first is a one-dimensional Markov chain (called time variant model, TV) and the second is a two-layered Markov model (called two layer time variant model, TLTV). Analyses and simulations show that the TLTV model exhibits the best results