Abstract: Regarding to rapid development of the multimedia satellite networks, a novel analytical model was proposed to study the performances of low earth orbit （LEO） satellite networks  in a quantitative mode. In this model, the mapping relationship of discrete time traffic and topology （DT-TT） was established according to the dynamic characteristics of a constellation topology and complicated global traffic. Based on Markov process theory and the constraints of link capacity, some quantitative formulas of the performance indexes, in terms of blocking probability and end-to-end delay, were derived by using probability analysis method on real-time and non real-time traffic. Numerous simulation and numerical results show the validity and correctness of the methodology. The proposed method can be also applied to the design of QoS routing control and resource allocation for multimedia LEO satellite networks. 

Key words: LEO satellite networks, Multimedia traffic, Block probability, End-to-end delay, Discrete-time topology