On Reducing Blocking Probability in Cooperative Ad-hoc Networks

In this paper, we propose a new channel access protocol for transmission over cooperative ad-hoc networks. The proposed protocol, which aims at minimizing the number of blocked nodes and consequently improving the system throughput, employs directional antennas at both source and relay stations. The network performance under the proposed settings is modelled using continues Markov chains. Steady state transmission blocking probability and average network throughput are obtained by analyzing the Markov model. Both analytical and simulation results show the improvement in performance compared to carrier sense multiple access with collision avoidance protocol that employs omnidirectional antennas.