Non-Asymptotic Capacity Study in Multicast Mobile Ad Hoc Networks

Extensive efforts on capacity studies for the mobile ad hoc networks (MANETs) mainly focus on either the unicast traffic or the asymptotic results under multicast traffic. However, the former ones cannot support future multicast-intensive applications, and the latter ones cannot reveal the real achievable non-asymptotic capacity, such that it still remains largely unknown in such networks. This paper, for the first time, investigates the non-asymptotic capacity in MANETs under a general packet routing scheme with multicast traffic, where each source has multiple destinations. Under the routing scheme, when the destinations move into the communication range of their source, a packet at source will be directly sent to destinations; otherwise, it can be replicated to multiple different relays, which help to forward it to destinations. To study the non-asymptotic capacity in the MANETs, we first develop the two Markov chain theoretical frameworks to characterize the fastest packet propagation process at source and the fastest packet reception process at destinations under the routing scheme. Based on these two theoretical frameworks, we then derive an analytical expression for the capacity. Finally, the simulation and numerical results are conducted to validate our theoretical capacity and also to explore the impact of system parameters on the capacity performance.