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To mitigate performance anomalies due to different transmission rates and to improve throughput performance in ad-hoc networks, a previous work has proposed a new method called user cooperative mobility. It also showed that the method achieved good improvement when users appropriately move. However, it only employed theoretical evaluation which does not include detailed behavior such as capture effect or dynamic back-off time. We here employ NS3 network simulator to investigate differs from theoretical one. The result shows that capture effect and dynamic back-off time significantly affected on the transmitting opportunity, which leads to a huge difference in system throughput. The difference varies widely according to user mobility, by 172% at maximum and nearly 0 % at minimum. Thus, we conclude that theoretical evaluation requires a correction based on user mobility, in case of unequal transmitting opportunity for each node.

To mitigate performance anomalies due to different transmission rates and improve throughput performance in ad-hoc networks, we propose a method called user cooperative mobility in which a node, i.e., a user of an ad-hoc network, moves (changes its geometrical position) for communication. Unlike previous research regarding user cooperative mobility, it is not easy to decide to where the user should move to obtain the best result because the move may change multiple transmission rates in multiple links. Thus, we show that the best position to move to is quite different from the intuitively best position on the way to the next hop. We first evaluate throughput characteristics at every position within a movable distance from the original position of the cooperative mobility user. Then, we compare differences in throughput and direction of movement between the following three movement strategies: the best move, the intuitive move and no move. In terms of throughput improvement, which is normalized by the throughput of no move, the best move results were 40% better than those of no move and 24% better than those of the intuitive move. The direction of movement significantly differed from the intuitive move, by 92 degrees at the maximum. We conclude that cooperative user mobility with the best move is beneficial for both cooperative mobility users and ad-hoc networks.