Summary: | 碩士 === 國立臺灣大學 === 電信工程學研究所 === 102 === Traditional analysis and design on random access systems do not take sensing topology into consideration, which implicitly assumes that one user can sense all other users. The corresponding hidden terminal problem is only mitigated by some engineering techniques but never completely understood from a network view. This work applies random graph on imperfect sensing topology to study three random access systems: ALOHA, cognitive radio networks and CSMA. To avoiding misleading conclusion from equilibrium analysis, we take a dynamic approach by modeling the systems as Markov chains, and investigate the system stabiliby from the recurrence of Markov chains with the aid of Foster-Lyapunov criteria. Elegant stability conditions are derived in this work, together with the verification from simulation result.
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