Capacity of Mobile Ad Hoc Networks Using an Airborne Relay

Abstract

Self-organizing wireless networks is an interesting technology with a potential of providing robust communication in environments without existing infrastructure and a minimum of configuration. Such features seem especially relevant for the tactical domain, with a high degree of mobility and an increasing demand for information. While ad hoc networks show promise when it comes to robustness, a lot of research point out how the capacity can be a challenge. Wireless communication is confined by the shared medium within the range of the radio and forwarding leads to fewer resources available to each station.

One proposal to address the challenges of Mobile Ad hoc Networks (MANET) is to use Unmanned Areal Vehicles (UAV) with communication capabilities. A UAV can serve as a relay placed above communicating ground stations and provide a path with fewer hops. Communication over fewer hops can lead to lower delay at the same time as the ground network is offloaded.

The Norwegian Defence Research Establishment (FFI) have an exper- imental lightweight communication module equipped with wireless IP interfaces. The module is able to run MANET routing protocols. This thesis aims to introduce readers to relevant technologies and challenges present in mobile ad hoc networks. Based on this knowledge, the thesis develops and measures the performance of networks utilizing a UAV as a relay.

From the measurements, this thesis finds that there are scenarios where an airborne relay can provide low latency communication. In a grid of nodes, simulation imply that by forwarding data destined to nodes with many hops through a two hop relay path lower delay can be obtained.