부산대학교 도서관

Communications among mobile, tactical nodes presents a major military challenge. The use of MANET (Mobile Ad Hoc Network) protocols provides a possible solution for military nodes, including those in an airborne network. However MANET research has primarily focused on ground-based studies, using vehicular speeds and in many cases random mobility patterns. Nodes of an airborne network travel at speeds significantly faster than ground vehicles, and fly in coordinated paths not modeled by random mobility. In addition, the quality of the radio links for airborne nodes varies with time, due to interference, range, or antenna occlusion when banking. These characteristics make it impossible to extrapolate existing MANET research results to the airborne network. In this paper we present a simulation evaluation of MANET protocol performance for an airborne environment, with the intent to identify a routing protocol that can best deal with the dynamics of an airborne network. A scenario involving widebody aircraft trajectories was modeled in OPNET. Intermittent link outages due to aircraft banking were modeled by use of a notional radio link, antenna model, and modified OPNET source code that reflects positional antenna gain, including antenna occlusion when an aircraft banks. Within this scenario environment, four MANET protocols (AODV, TORA, OLSR, OSPFv3-MANET) were run on the airborne nodes with metric collection of protocol overhead, packet delivery ratio, and packet delay. Simulation results and analysis of the protocol performance for an airborne network are presented here. Additional issues and future areas of research are also identified.