Spatial distribution analysis with capture effect of a mobile S-ALOHA network

The throughput performance of a mobile S-ALOHA network can be improved considering the capture phenomenon, which also depends on the spatial distribution of the mobiles within the cell. We have studied the capture probabilities that arise in a mobile radio scenario in the presence of fading and shadowing, and considering both, uniform and non-uniform spatial distribution models. In particular we were interested in the limit behaviour of these models, which has been shown to be directly related to the capture probability. This analysis allows a quantitative comparison of three spatial distribution models for mobile users under real mobile channels. The use of an exponential backoff retransmission algorithm is considered. With these assumptions the performance of the anarchic ALOHA is improved considerably obtaining higher throughput values with stabilised behaviour and lower delays values.