A Logic Flattened Routing Scheme For The Air-Ground Networks

In order to cover mountains and seas by the communication networks, and to cope with the damage on the terrestrial communication networks by the earthquakes or hurricanes, it is necessary to make research on and construct the Integrated Space-Air-Ground Communication Networks(ISAGN). The near space networks, which is located between the satellite networks and terrestrial communication networks, plays an important role in the ISAGN. This paper takes ISAGN as the background, and focuses on the Air-Ground networks which is composed of the near space networks and the terrestrial communication networks. As for the satellite networks, we take it as the complement for the Air-Ground networks. And we mainly do research on the routing problem in the Air-Ground networks.This paper firstly presents the Air-Ground networks system, including the network structure, the characteristics of each subnet and so on. In order to route in this system, this paper presents the routing types. Combining the routing types with the characteristics of the Air-Ground networks, we get that we need a dynamic, semicentralized, semi-distributed and integrated routing method.Then, we give the research status on the Air-Ground networks. United with the routing requests of the Air-Ground networks, we obtain the logic flattened routing scheme. This scheme flattens the two layers of network topology to a single topology which contains all the topology information of the former. With the flattened topology, we can get the best route to the destination. To realize the logic flattened routing scheme, we should find a uniform method to measure the different channels in the Air-Ground networks, and we call it the link metric. To sufficiently distinguish the wire channel and the wireless channel, this paper provides a new link metric m ETT(mobility ETT). This metric can simultaneously measure link properties in delay, bandwidth, packet loss and stability.Finally, we use the OPNET simulator to simulate the logic flattened routing scheme and the m ETT link metric. The results tell us that the logic flattened routing scheme is better than the traditional layered routing scheme in aspect of packet delivery ratio, packet delay and so on. We also justify the m ETT link metric can measure link properties in four aspects. If we apply the logic flattened routing scheme and the m ETT to the Air- Ground networks, I believe we can simplify the designing complexity of the near space platform and improve the transmission property of the Air-Ground networks.